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//===---- TargetInfo.cpp - Encapsulate target details -----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// These classes wrap the information about a call or function
// definition used to handle ABI compliancy.
//
//===----------------------------------------------------------------------===//
#include "TargetInfo.h"
#include "ABIInfo.h"
#include "CGCXXABI.h"
#include "CGValue.h"
#include "CodeGenFunction.h"
#include "clang/AST/RecordLayout.h"
#include "clang/CodeGen/CGFunctionInfo.h"
#include "clang/Frontend/CodeGenOptions.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Triple.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm> // std::sort
using namespace clang;
using namespace CodeGen;
// Helper for coercing an aggregate argument or return value into an
// integer array of the same size (including padding).
//
// This is needed for RenderScript on ARM targets. The RenderScript
// compiler assumes that the size of the argument / return value in
// the IR is the same as the size of the corresponding qualified
// type. It is necessary to coerce the aggregate type into an
// array. We cannot pass a struct directly as an argument because
// clang's struct passing logic breaks up the struct into its
// constitutent fields.
//
// Ty - The argument / return value type
// Context - The associated ASTContext
// LLVMContext - The associated LLVMContext
static ABIArgInfo coerceToIntArray(QualType Ty,
ASTContext &Context,
llvm::LLVMContext &LLVMContext) {
// Alignment and Size are measured in bits.
const uint64_t Size = Context.getTypeSize(Ty);
const uint64_t Alignment = Context.getTypeAlign(Ty);
llvm::Type *IntType = llvm::Type::getIntNTy(LLVMContext, Alignment);
const uint64_t NumElements = (Size + Alignment - 1) / Alignment;
return ABIArgInfo::getDirect(llvm::ArrayType::get(IntType, NumElements));
}
static void AssignToArrayRange(CodeGen::CGBuilderTy &Builder,
llvm::Value *Array,
llvm::Value *Value,
unsigned FirstIndex,
unsigned LastIndex) {
// Alternatively, we could emit this as a loop in the source.
for (unsigned I = FirstIndex; I <= LastIndex; ++I) {
llvm::Value *Cell =
Builder.CreateConstInBoundsGEP1_32(Builder.getInt8Ty(), Array, I);
Builder.CreateAlignedStore(Value, Cell, CharUnits::One());
}
}
static bool isAggregateTypeForABI(QualType T) {
return !CodeGenFunction::hasScalarEvaluationKind(T) ||
T->isMemberFunctionPointerType();
}
ABIArgInfo
ABIInfo::getNaturalAlignIndirect(QualType Ty, bool ByRef, bool Realign,
llvm::Type *Padding) const {
return ABIArgInfo::getIndirect(getContext().getTypeAlignInChars(Ty),
ByRef, Realign, Padding);
}
ABIArgInfo
ABIInfo::getNaturalAlignIndirectInReg(QualType Ty, bool Realign) const {
return ABIArgInfo::getIndirectInReg(getContext().getTypeAlignInChars(Ty),
/*ByRef*/ false, Realign);
}
Address ABIInfo::EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
return Address::invalid();
}
ABIInfo::~ABIInfo() {}
static CGCXXABI::RecordArgABI getRecordArgABI(const RecordType *RT,
CGCXXABI &CXXABI) {
const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
if (!RD)
return CGCXXABI::RAA_Default;
return CXXABI.getRecordArgABI(RD);
}
static CGCXXABI::RecordArgABI getRecordArgABI(QualType T,
CGCXXABI &CXXABI) {
const RecordType *RT = T->getAs<RecordType>();
if (!RT)
return CGCXXABI::RAA_Default;
return getRecordArgABI(RT, CXXABI);
}
/// Pass transparent unions as if they were the type of the first element. Sema
/// should ensure that all elements of the union have the same "machine type".
static QualType useFirstFieldIfTransparentUnion(QualType Ty) {
if (const RecordType *UT = Ty->getAsUnionType()) {
const RecordDecl *UD = UT->getDecl();
if (UD->hasAttr<TransparentUnionAttr>()) {
assert(!UD->field_empty() && "sema created an empty transparent union");
return UD->field_begin()->getType();
}
}
return Ty;
}
CGCXXABI &ABIInfo::getCXXABI() const {
return CGT.getCXXABI();
}
ASTContext &ABIInfo::getContext() const {
return CGT.getContext();
}
llvm::LLVMContext &ABIInfo::getVMContext() const {
return CGT.getLLVMContext();
}
const llvm::DataLayout &ABIInfo::getDataLayout() const {
return CGT.getDataLayout();
}
const TargetInfo &ABIInfo::getTarget() const {
return CGT.getTarget();
}
bool ABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
return false;
}
bool ABIInfo::isHomogeneousAggregateSmallEnough(const Type *Base,
uint64_t Members) const {
return false;
}
bool ABIInfo::shouldSignExtUnsignedType(QualType Ty) const {
return false;
}
void ABIArgInfo::dump() const {
raw_ostream &OS = llvm::errs();
OS << "(ABIArgInfo Kind=";
switch (TheKind) {
case Direct:
OS << "Direct Type=";
if (llvm::Type *Ty = getCoerceToType())
Ty->print(OS);
else
OS << "null";
break;
case Extend:
OS << "Extend";
break;
case Ignore:
OS << "Ignore";
break;
case InAlloca:
OS << "InAlloca Offset=" << getInAllocaFieldIndex();
break;
case Indirect:
OS << "Indirect Align=" << getIndirectAlign().getQuantity()
<< " ByVal=" << getIndirectByVal()
<< " Realign=" << getIndirectRealign();
break;
case Expand:
OS << "Expand";
break;
}
OS << ")\n";
}
// Dynamically round a pointer up to a multiple of the given alignment.
static llvm::Value *emitRoundPointerUpToAlignment(CodeGenFunction &CGF,
llvm::Value *Ptr,
CharUnits Align) {
llvm::Value *PtrAsInt = Ptr;
// OverflowArgArea = (OverflowArgArea + Align - 1) & -Align;
PtrAsInt = CGF.Builder.CreatePtrToInt(PtrAsInt, CGF.IntPtrTy);
PtrAsInt = CGF.Builder.CreateAdd(PtrAsInt,
llvm::ConstantInt::get(CGF.IntPtrTy, Align.getQuantity() - 1));
PtrAsInt = CGF.Builder.CreateAnd(PtrAsInt,
llvm::ConstantInt::get(CGF.IntPtrTy, -Align.getQuantity()));
PtrAsInt = CGF.Builder.CreateIntToPtr(PtrAsInt,
Ptr->getType(),
Ptr->getName() + ".aligned");
return PtrAsInt;
}
/// Emit va_arg for a platform using the common void* representation,
/// where arguments are simply emitted in an array of slots on the stack.
///
/// This version implements the core direct-value passing rules.
///
/// \param SlotSize - The size and alignment of a stack slot.
/// Each argument will be allocated to a multiple of this number of
/// slots, and all the slots will be aligned to this value.
/// \param AllowHigherAlign - The slot alignment is not a cap;
/// an argument type with an alignment greater than the slot size
/// will be emitted on a higher-alignment address, potentially
/// leaving one or more empty slots behind as padding. If this
/// is false, the returned address might be less-aligned than
/// DirectAlign.
static Address emitVoidPtrDirectVAArg(CodeGenFunction &CGF,
Address VAListAddr,
llvm::Type *DirectTy,
CharUnits DirectSize,
CharUnits DirectAlign,
CharUnits SlotSize,
bool AllowHigherAlign) {
// Cast the element type to i8* if necessary. Some platforms define
// va_list as a struct containing an i8* instead of just an i8*.
if (VAListAddr.getElementType() != CGF.Int8PtrTy)
VAListAddr = CGF.Builder.CreateElementBitCast(VAListAddr, CGF.Int8PtrTy);
llvm::Value *Ptr = CGF.Builder.CreateLoad(VAListAddr, "argp.cur");
// If the CC aligns values higher than the slot size, do so if needed.
Address Addr = Address::invalid();
if (AllowHigherAlign && DirectAlign > SlotSize) {
Addr = Address(emitRoundPointerUpToAlignment(CGF, Ptr, DirectAlign),
DirectAlign);
} else {
Addr = Address(Ptr, SlotSize);
}
// Advance the pointer past the argument, then store that back.
CharUnits FullDirectSize = DirectSize.RoundUpToAlignment(SlotSize);
llvm::Value *NextPtr =
CGF.Builder.CreateConstInBoundsByteGEP(Addr.getPointer(), FullDirectSize,
"argp.next");
CGF.Builder.CreateStore(NextPtr, VAListAddr);
// If the argument is smaller than a slot, and this is a big-endian
// target, the argument will be right-adjusted in its slot.
if (DirectSize < SlotSize && CGF.CGM.getDataLayout().isBigEndian()) {
Addr = CGF.Builder.CreateConstInBoundsByteGEP(Addr, SlotSize - DirectSize);
}
Addr = CGF.Builder.CreateElementBitCast(Addr, DirectTy);
return Addr;
}
/// Emit va_arg for a platform using the common void* representation,
/// where arguments are simply emitted in an array of slots on the stack.
///
/// \param IsIndirect - Values of this type are passed indirectly.
/// \param ValueInfo - The size and alignment of this type, generally
/// computed with getContext().getTypeInfoInChars(ValueTy).
/// \param SlotSizeAndAlign - The size and alignment of a stack slot.
/// Each argument will be allocated to a multiple of this number of
/// slots, and all the slots will be aligned to this value.
/// \param AllowHigherAlign - The slot alignment is not a cap;
/// an argument type with an alignment greater than the slot size
/// will be emitted on a higher-alignment address, potentially
/// leaving one or more empty slots behind as padding.
static Address emitVoidPtrVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType ValueTy, bool IsIndirect,
std::pair<CharUnits, CharUnits> ValueInfo,
CharUnits SlotSizeAndAlign,
bool AllowHigherAlign) {
// The size and alignment of the value that was passed directly.
CharUnits DirectSize, DirectAlign;
if (IsIndirect) {
DirectSize = CGF.getPointerSize();
DirectAlign = CGF.getPointerAlign();
} else {
DirectSize = ValueInfo.first;
DirectAlign = ValueInfo.second;
}
// Cast the address we've calculated to the right type.
llvm::Type *DirectTy = CGF.ConvertTypeForMem(ValueTy);
if (IsIndirect)
DirectTy = DirectTy->getPointerTo(0);
Address Addr = emitVoidPtrDirectVAArg(CGF, VAListAddr, DirectTy,
DirectSize, DirectAlign,
SlotSizeAndAlign,
AllowHigherAlign);
if (IsIndirect) {
Addr = Address(CGF.Builder.CreateLoad(Addr), ValueInfo.second);
}
return Addr;
}
static Address emitMergePHI(CodeGenFunction &CGF,
Address Addr1, llvm::BasicBlock *Block1,
Address Addr2, llvm::BasicBlock *Block2,
const llvm::Twine &Name = "") {
assert(Addr1.getType() == Addr2.getType());
llvm::PHINode *PHI = CGF.Builder.CreatePHI(Addr1.getType(), 2, Name);
PHI->addIncoming(Addr1.getPointer(), Block1);
PHI->addIncoming(Addr2.getPointer(), Block2);
CharUnits Align = std::min(Addr1.getAlignment(), Addr2.getAlignment());
return Address(PHI, Align);
}
TargetCodeGenInfo::~TargetCodeGenInfo() { delete Info; }
// If someone can figure out a general rule for this, that would be great.
// It's probably just doomed to be platform-dependent, though.
unsigned TargetCodeGenInfo::getSizeOfUnwindException() const {
// Verified for:
// x86-64 FreeBSD, Linux, Darwin
// x86-32 FreeBSD, Linux, Darwin
// PowerPC Linux, Darwin
// ARM Darwin (*not* EABI)
// AArch64 Linux
return 32;
}
bool TargetCodeGenInfo::isNoProtoCallVariadic(const CallArgList &args,
const FunctionNoProtoType *fnType) const {
// The following conventions are known to require this to be false:
// x86_stdcall
// MIPS
// For everything else, we just prefer false unless we opt out.
return false;
}
void
TargetCodeGenInfo::getDependentLibraryOption(llvm::StringRef Lib,
llvm::SmallString<24> &Opt) const {
// This assumes the user is passing a library name like "rt" instead of a
// filename like "librt.a/so", and that they don't care whether it's static or
// dynamic.
Opt = "-l";
Opt += Lib;
}
static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays);
/// isEmptyField - Return true iff a the field is "empty", that is it
/// is an unnamed bit-field or an (array of) empty record(s).
static bool isEmptyField(ASTContext &Context, const FieldDecl *FD,
bool AllowArrays) {
if (FD->isUnnamedBitfield())
return true;
QualType FT = FD->getType();
// Constant arrays of empty records count as empty, strip them off.
// Constant arrays of zero length always count as empty.
if (AllowArrays)
while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
if (AT->getSize() == 0)
return true;
FT = AT->getElementType();
}
const RecordType *RT = FT->getAs<RecordType>();
if (!RT)
return false;
// C++ record fields are never empty, at least in the Itanium ABI.
//
// FIXME: We should use a predicate for whether this behavior is true in the
// current ABI.
if (isa<CXXRecordDecl>(RT->getDecl()))
return false;
return isEmptyRecord(Context, FT, AllowArrays);
}
/// isEmptyRecord - Return true iff a structure contains only empty
/// fields. Note that a structure with a flexible array member is not
/// considered empty.
static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays) {
const RecordType *RT = T->getAs<RecordType>();
if (!RT)
return 0;
const RecordDecl *RD = RT->getDecl();
if (RD->hasFlexibleArrayMember())
return false;
// If this is a C++ record, check the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
for (const auto &I : CXXRD->bases())
if (!isEmptyRecord(Context, I.getType(), true))
return false;
for (const auto *I : RD->fields())
if (!isEmptyField(Context, I, AllowArrays))
return false;
return true;
}
/// isSingleElementStruct - Determine if a structure is a "single
/// element struct", i.e. it has exactly one non-empty field or
/// exactly one field which is itself a single element
/// struct. Structures with flexible array members are never
/// considered single element structs.
///
/// \return The field declaration for the single non-empty field, if
/// it exists.
static const Type *isSingleElementStruct(QualType T, ASTContext &Context) {
const RecordType *RT = T->getAs<RecordType>();
if (!RT)
return nullptr;
const RecordDecl *RD = RT->getDecl();
if (RD->hasFlexibleArrayMember())
return nullptr;
const Type *Found = nullptr;
// If this is a C++ record, check the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
for (const auto &I : CXXRD->bases()) {
// Ignore empty records.
if (isEmptyRecord(Context, I.getType(), true))
continue;
// If we already found an element then this isn't a single-element struct.
if (Found)
return nullptr;
// If this is non-empty and not a single element struct, the composite
// cannot be a single element struct.
Found = isSingleElementStruct(I.getType(), Context);
if (!Found)
return nullptr;
}
}
// Check for single element.
for (const auto *FD : RD->fields()) {
QualType FT = FD->getType();
// Ignore empty fields.
if (isEmptyField(Context, FD, true))
continue;
// If we already found an element then this isn't a single-element
// struct.
if (Found)
return nullptr;
// Treat single element arrays as the element.
while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
if (AT->getSize().getZExtValue() != 1)
break;
FT = AT->getElementType();
}
if (!isAggregateTypeForABI(FT)) {
Found = FT.getTypePtr();
} else {
Found = isSingleElementStruct(FT, Context);
if (!Found)
return nullptr;
}
}
// We don't consider a struct a single-element struct if it has
// padding beyond the element type.
if (Found && Context.getTypeSize(Found) != Context.getTypeSize(T))
return nullptr;
return Found;
}
static bool is32Or64BitBasicType(QualType Ty, ASTContext &Context) {
// Treat complex types as the element type.
if (const ComplexType *CTy = Ty->getAs<ComplexType>())
Ty = CTy->getElementType();
// Check for a type which we know has a simple scalar argument-passing
// convention without any padding. (We're specifically looking for 32
// and 64-bit integer and integer-equivalents, float, and double.)
if (!Ty->getAs<BuiltinType>() && !Ty->hasPointerRepresentation() &&
!Ty->isEnumeralType() && !Ty->isBlockPointerType())
return false;
uint64_t Size = Context.getTypeSize(Ty);
return Size == 32 || Size == 64;
}
/// canExpandIndirectArgument - Test whether an argument type which is to be
/// passed indirectly (on the stack) would have the equivalent layout if it was
/// expanded into separate arguments. If so, we prefer to do the latter to avoid
/// inhibiting optimizations.
///
// FIXME: This predicate is missing many cases, currently it just follows
// llvm-gcc (checks that all fields are 32-bit or 64-bit primitive types). We
// should probably make this smarter, or better yet make the LLVM backend
// capable of handling it.
static bool canExpandIndirectArgument(QualType Ty, ASTContext &Context) {
// We can only expand structure types.
const RecordType *RT = Ty->getAs<RecordType>();
if (!RT)
return false;
// We can only expand (C) structures.
//
// FIXME: This needs to be generalized to handle classes as well.
const RecordDecl *RD = RT->getDecl();
if (!RD->isStruct())
return false;
// We try to expand CLike CXXRecordDecl.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
if (!CXXRD->isCLike())
return false;
}
uint64_t Size = 0;
for (const auto *FD : RD->fields()) {
if (!is32Or64BitBasicType(FD->getType(), Context))
return false;
// FIXME: Reject bit-fields wholesale; there are two problems, we don't know
// how to expand them yet, and the predicate for telling if a bitfield still
// counts as "basic" is more complicated than what we were doing previously.
if (FD->isBitField())
return false;
Size += Context.getTypeSize(FD->getType());
}
// Make sure there are not any holes in the struct.
if (Size != Context.getTypeSize(Ty))
return false;
return true;
}
namespace {
/// DefaultABIInfo - The default implementation for ABI specific
/// details. This implementation provides information which results in
/// self-consistent and sensible LLVM IR generation, but does not
/// conform to any particular ABI.
class DefaultABIInfo : public ABIInfo {
public:
DefaultABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType RetTy) const;
void computeInfo(CGFunctionInfo &FI) const override {
if (!getCXXABI().classifyReturnType(FI))
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (auto &I : FI.arguments())
I.info = classifyArgumentType(I.type);
}
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
};
class DefaultTargetCodeGenInfo : public TargetCodeGenInfo {
public:
DefaultTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
: TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
};
Address DefaultABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
return Address::invalid();
}
ABIArgInfo DefaultABIInfo::classifyArgumentType(QualType Ty) const {
Ty = useFirstFieldIfTransparentUnion(Ty);
if (isAggregateTypeForABI(Ty)) {
// Records with non-trivial destructors/copy-constructors should not be
// passed by value.
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
return getNaturalAlignIndirect(Ty);
}
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
ABIArgInfo DefaultABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
if (isAggregateTypeForABI(RetTy))
return getNaturalAlignIndirect(RetTy);
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
//===----------------------------------------------------------------------===//
// WebAssembly ABI Implementation
//
// This is a very simple ABI that relies a lot on DefaultABIInfo.
//===----------------------------------------------------------------------===//
class WebAssemblyABIInfo final : public DefaultABIInfo {
public:
explicit WebAssemblyABIInfo(CodeGen::CodeGenTypes &CGT)
: DefaultABIInfo(CGT) {}
private:
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType Ty) const;
// DefaultABIInfo's classifyReturnType and classifyArgumentType are
// non-virtual, but computeInfo is virtual, so we overload that.
void computeInfo(CGFunctionInfo &FI) const override {
if (!getCXXABI().classifyReturnType(FI))
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (auto &Arg : FI.arguments())
Arg.info = classifyArgumentType(Arg.type);
}
};
class WebAssemblyTargetCodeGenInfo final : public TargetCodeGenInfo {
public:
explicit WebAssemblyTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
: TargetCodeGenInfo(new WebAssemblyABIInfo(CGT)) {}
};
/// \brief Classify argument of given type \p Ty.
ABIArgInfo WebAssemblyABIInfo::classifyArgumentType(QualType Ty) const {
Ty = useFirstFieldIfTransparentUnion(Ty);
if (isAggregateTypeForABI(Ty)) {
// Records with non-trivial destructors/copy-constructors should not be
// passed by value.
if (auto RAA = getRecordArgABI(Ty, getCXXABI()))
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
// Ignore empty structs/unions.
if (isEmptyRecord(getContext(), Ty, true))
return ABIArgInfo::getIgnore();
// Lower single-element structs to just pass a regular value. TODO: We
// could do reasonable-size multiple-element structs too, using getExpand(),
// though watch out for things like bitfields.
if (const Type *SeltTy = isSingleElementStruct(Ty, getContext()))
return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
}
// Otherwise just do the default thing.
return DefaultABIInfo::classifyArgumentType(Ty);
}
ABIArgInfo WebAssemblyABIInfo::classifyReturnType(QualType RetTy) const {
if (isAggregateTypeForABI(RetTy)) {
// Records with non-trivial destructors/copy-constructors should not be
// returned by value.
if (!getRecordArgABI(RetTy, getCXXABI())) {
// Ignore empty structs/unions.
if (isEmptyRecord(getContext(), RetTy, true))
return ABIArgInfo::getIgnore();
// Lower single-element structs to just return a regular value. TODO: We
// could do reasonable-size multiple-element structs too, using
// ABIArgInfo::getDirect().
if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
}
}
// Otherwise just do the default thing.
return DefaultABIInfo::classifyReturnType(RetTy);
}
//===----------------------------------------------------------------------===//
// le32/PNaCl bitcode ABI Implementation
//
// This is a simplified version of the x86_32 ABI. Arguments and return values
// are always passed on the stack.
//===----------------------------------------------------------------------===//
class PNaClABIInfo : public ABIInfo {
public:
PNaClABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType RetTy) const;
void computeInfo(CGFunctionInfo &FI) const override;
Address EmitVAArg(CodeGenFunction &CGF,
Address VAListAddr, QualType Ty) const override;
};
class PNaClTargetCodeGenInfo : public TargetCodeGenInfo {
public:
PNaClTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
: TargetCodeGenInfo(new PNaClABIInfo(CGT)) {}
};
void PNaClABIInfo::computeInfo(CGFunctionInfo &FI) const {
if (!getCXXABI().classifyReturnType(FI))
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (auto &I : FI.arguments())
I.info = classifyArgumentType(I.type);
}
Address PNaClABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
return Address::invalid();
}
/// \brief Classify argument of given type \p Ty.
ABIArgInfo PNaClABIInfo::classifyArgumentType(QualType Ty) const {
if (isAggregateTypeForABI(Ty)) {
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
return getNaturalAlignIndirect(Ty);
} else if (const EnumType *EnumTy = Ty->getAs<EnumType>()) {
// Treat an enum type as its underlying type.
Ty = EnumTy->getDecl()->getIntegerType();
} else if (Ty->isFloatingType()) {
// Floating-point types don't go inreg.
return ABIArgInfo::getDirect();
}
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
ABIArgInfo PNaClABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
// In the PNaCl ABI we always return records/structures on the stack.
if (isAggregateTypeForABI(RetTy))
return getNaturalAlignIndirect(RetTy);
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
/// IsX86_MMXType - Return true if this is an MMX type.
bool IsX86_MMXType(llvm::Type *IRType) {
// Return true if the type is an MMX type <2 x i32>, <4 x i16>, or <8 x i8>.
return IRType->isVectorTy() && IRType->getPrimitiveSizeInBits() == 64 &&
cast<llvm::VectorType>(IRType)->getElementType()->isIntegerTy() &&
IRType->getScalarSizeInBits() != 64;
}
static llvm::Type* X86AdjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
StringRef Constraint,
llvm::Type* Ty) {
if ((Constraint == "y" || Constraint == "&y") && Ty->isVectorTy()) {
if (cast<llvm::VectorType>(Ty)->getBitWidth() != 64) {
// Invalid MMX constraint
return nullptr;
}
return llvm::Type::getX86_MMXTy(CGF.getLLVMContext());
}
// No operation needed
return Ty;
}
/// Returns true if this type can be passed in SSE registers with the
/// X86_VectorCall calling convention. Shared between x86_32 and x86_64.
static bool isX86VectorTypeForVectorCall(ASTContext &Context, QualType Ty) {
if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
if (BT->isFloatingPoint() && BT->getKind() != BuiltinType::Half)
return true;
} else if (const VectorType *VT = Ty->getAs<VectorType>()) {
// vectorcall can pass XMM, YMM, and ZMM vectors. We don't pass SSE1 MMX
// registers specially.
unsigned VecSize = Context.getTypeSize(VT);
if (VecSize == 128 || VecSize == 256 || VecSize == 512)
return true;
}
return false;
}
/// Returns true if this aggregate is small enough to be passed in SSE registers
/// in the X86_VectorCall calling convention. Shared between x86_32 and x86_64.
static bool isX86VectorCallAggregateSmallEnough(uint64_t NumMembers) {
return NumMembers <= 4;
}
//===----------------------------------------------------------------------===//
// X86-32 ABI Implementation
//===----------------------------------------------------------------------===//
/// \brief Similar to llvm::CCState, but for Clang.
struct CCState {
CCState(unsigned CC) : CC(CC), FreeRegs(0), FreeSSERegs(0) {}
unsigned CC;
unsigned FreeRegs;
unsigned FreeSSERegs;
};
/// X86_32ABIInfo - The X86-32 ABI information.
class X86_32ABIInfo : public ABIInfo {
enum Class {
Integer,
Float
};
static const unsigned MinABIStackAlignInBytes = 4;
bool IsDarwinVectorABI;
bool IsRetSmallStructInRegABI;
bool IsWin32StructABI;
bool IsSoftFloatABI;
bool IsMCUABI;
unsigned DefaultNumRegisterParameters;
static bool isRegisterSize(unsigned Size) {
return (Size == 8 || Size == 16 || Size == 32 || Size == 64);
}
bool isHomogeneousAggregateBaseType(QualType Ty) const override {
// FIXME: Assumes vectorcall is in use.
return isX86VectorTypeForVectorCall(getContext(), Ty);
}
bool isHomogeneousAggregateSmallEnough(const Type *Ty,
uint64_t NumMembers) const override {
// FIXME: Assumes vectorcall is in use.
return isX86VectorCallAggregateSmallEnough(NumMembers);
}
bool shouldReturnTypeInRegister(QualType Ty, ASTContext &Context) const;
/// getIndirectResult - Give a source type \arg Ty, return a suitable result
/// such that the argument will be passed in memory.
ABIArgInfo getIndirectResult(QualType Ty, bool ByVal, CCState &State) const;
ABIArgInfo getIndirectReturnResult(QualType Ty, CCState &State) const;
/// \brief Return the alignment to use for the given type on the stack.
unsigned getTypeStackAlignInBytes(QualType Ty, unsigned Align) const;
Class classify(QualType Ty) const;
ABIArgInfo classifyReturnType(QualType RetTy, CCState &State) const;
ABIArgInfo classifyArgumentType(QualType RetTy, CCState &State) const;
bool shouldUseInReg(QualType Ty, CCState &State, bool &NeedsPadding) const;
/// \brief Rewrite the function info so that all memory arguments use
/// inalloca.
void rewriteWithInAlloca(CGFunctionInfo &FI) const;
void addFieldToArgStruct(SmallVector<llvm::Type *, 6> &FrameFields,
CharUnits &StackOffset, ABIArgInfo &Info,
QualType Type) const;
public:
void computeInfo(CGFunctionInfo &FI) const override;
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
X86_32ABIInfo(CodeGen::CodeGenTypes &CGT, bool DarwinVectorABI,
bool RetSmallStructInRegABI, bool Win32StructABI,
unsigned NumRegisterParameters, bool SoftFloatABI)
: ABIInfo(CGT), IsDarwinVectorABI(DarwinVectorABI),
IsRetSmallStructInRegABI(RetSmallStructInRegABI),
IsWin32StructABI(Win32StructABI),
IsSoftFloatABI(SoftFloatABI),
IsMCUABI(CGT.getTarget().getTriple().isOSIAMCU()),
DefaultNumRegisterParameters(NumRegisterParameters) {}
};
class X86_32TargetCodeGenInfo : public TargetCodeGenInfo {
public:
X86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool DarwinVectorABI,
bool RetSmallStructInRegABI, bool Win32StructABI,
unsigned NumRegisterParameters, bool SoftFloatABI)
: TargetCodeGenInfo(new X86_32ABIInfo(
CGT, DarwinVectorABI, RetSmallStructInRegABI, Win32StructABI,
NumRegisterParameters, SoftFloatABI)) {}
static bool isStructReturnInRegABI(
const llvm::Triple &Triple, const CodeGenOptions &Opts);
void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const override;
int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
// Darwin uses different dwarf register numbers for EH.
if (CGM.getTarget().getTriple().isOSDarwin()) return 5;
return 4;
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const override;
llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
StringRef Constraint,
llvm::Type* Ty) const override {
return X86AdjustInlineAsmType(CGF, Constraint, Ty);
}
void addReturnRegisterOutputs(CodeGenFunction &CGF, LValue ReturnValue,
std::string &Constraints,
std::vector<llvm::Type *> &ResultRegTypes,
std::vector<llvm::Type *> &ResultTruncRegTypes,
std::vector<LValue> &ResultRegDests,
std::string &AsmString,
unsigned NumOutputs) const override;
llvm::Constant *
getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const override {
unsigned Sig = (0xeb << 0) | // jmp rel8
(0x06 << 8) | // .+0x08
('F' << 16) |
('T' << 24);
return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
}
};
}
/// Rewrite input constraint references after adding some output constraints.
/// In the case where there is one output and one input and we add one output,
/// we need to replace all operand references greater than or equal to 1:
/// mov $0, $1
/// mov eax, $1
/// The result will be:
/// mov $0, $2
/// mov eax, $2
static void rewriteInputConstraintReferences(unsigned FirstIn,
unsigned NumNewOuts,
std::string &AsmString) {
std::string Buf;
llvm::raw_string_ostream OS(Buf);
size_t Pos = 0;
while (Pos < AsmString.size()) {
size_t DollarStart = AsmString.find('$', Pos);
if (DollarStart == std::string::npos)
DollarStart = AsmString.size();
size_t DollarEnd = AsmString.find_first_not_of('$', DollarStart);
if (DollarEnd == std::string::npos)
DollarEnd = AsmString.size();
OS << StringRef(&AsmString[Pos], DollarEnd - Pos);
Pos = DollarEnd;
size_t NumDollars = DollarEnd - DollarStart;
if (NumDollars % 2 != 0 && Pos < AsmString.size()) {
// We have an operand reference.
size_t DigitStart = Pos;
size_t DigitEnd = AsmString.find_first_not_of("0123456789", DigitStart);
if (DigitEnd == std::string::npos)
DigitEnd = AsmString.size();
StringRef OperandStr(&AsmString[DigitStart], DigitEnd - DigitStart);
unsigned OperandIndex;
if (!OperandStr.getAsInteger(10, OperandIndex)) {
if (OperandIndex >= FirstIn)
OperandIndex += NumNewOuts;
OS << OperandIndex;
} else {
OS << OperandStr;
}
Pos = DigitEnd;
}
}
AsmString = std::move(OS.str());
}
/// Add output constraints for EAX:EDX because they are return registers.
void X86_32TargetCodeGenInfo::addReturnRegisterOutputs(
CodeGenFunction &CGF, LValue ReturnSlot, std::string &Constraints,
std::vector<llvm::Type *> &ResultRegTypes,
std::vector<llvm::Type *> &ResultTruncRegTypes,
std::vector<LValue> &ResultRegDests, std::string &AsmString,
unsigned NumOutputs) const {
uint64_t RetWidth = CGF.getContext().getTypeSize(ReturnSlot.getType());
// Use the EAX constraint if the width is 32 or smaller and EAX:EDX if it is
// larger.
if (!Constraints.empty())
Constraints += ',';
if (RetWidth <= 32) {
Constraints += "={eax}";
ResultRegTypes.push_back(CGF.Int32Ty);
} else {
// Use the 'A' constraint for EAX:EDX.
Constraints += "=A";
ResultRegTypes.push_back(CGF.Int64Ty);
}
// Truncate EAX or EAX:EDX to an integer of the appropriate size.
llvm::Type *CoerceTy = llvm::IntegerType::get(CGF.getLLVMContext(), RetWidth);
ResultTruncRegTypes.push_back(CoerceTy);
// Coerce the integer by bitcasting the return slot pointer.
ReturnSlot.setAddress(CGF.Builder.CreateBitCast(ReturnSlot.getAddress(),
CoerceTy->getPointerTo()));
ResultRegDests.push_back(ReturnSlot);
rewriteInputConstraintReferences(NumOutputs, 1, AsmString);
}
/// shouldReturnTypeInRegister - Determine if the given type should be
/// returned in a register (for the Darwin and MCU ABI).
bool X86_32ABIInfo::shouldReturnTypeInRegister(QualType Ty,
ASTContext &Context) const {
uint64_t Size = Context.getTypeSize(Ty);
// Type must be register sized.
if (!isRegisterSize(Size))
return false;
if (Ty->isVectorType()) {
// 64- and 128- bit vectors inside structures are not returned in
// registers.
if (Size == 64 || Size == 128)
return false;
return true;
}
// If this is a builtin, pointer, enum, complex type, member pointer, or
// member function pointer it is ok.
if (Ty->getAs<BuiltinType>() || Ty->hasPointerRepresentation() ||
Ty->isAnyComplexType() || Ty->isEnumeralType() ||
Ty->isBlockPointerType() || Ty->isMemberPointerType())
return true;
// Arrays are treated like records.
if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty))
return shouldReturnTypeInRegister(AT->getElementType(), Context);
// Otherwise, it must be a record type.
const RecordType *RT = Ty->getAs<RecordType>();
if (!RT) return false;
// FIXME: Traverse bases here too.
// Structure types are passed in register if all fields would be
// passed in a register.
for (const auto *FD : RT->getDecl()->fields()) {
// Empty fields are ignored.
if (isEmptyField(Context, FD, true))
continue;
// Check fields recursively.
if (!shouldReturnTypeInRegister(FD->getType(), Context))
return false;
}
return true;
}
ABIArgInfo X86_32ABIInfo::getIndirectReturnResult(QualType RetTy, CCState &State) const {
// If the return value is indirect, then the hidden argument is consuming one
// integer register.
if (State.FreeRegs) {
--State.FreeRegs;
return getNaturalAlignIndirectInReg(RetTy);
}
return getNaturalAlignIndirect(RetTy, /*ByVal=*/false);
}
ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy,
CCState &State) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
const Type *Base = nullptr;
uint64_t NumElts = 0;
if (State.CC == llvm::CallingConv::X86_VectorCall &&
isHomogeneousAggregate(RetTy, Base, NumElts)) {
// The LLVM struct type for such an aggregate should lower properly.
return ABIArgInfo::getDirect();
}
if (const VectorType *VT = RetTy->getAs<VectorType>()) {
// On Darwin, some vectors are returned in registers.
if (IsDarwinVectorABI) {
uint64_t Size = getContext().getTypeSize(RetTy);
// 128-bit vectors are a special case; they are returned in
// registers and we need to make sure to pick a type the LLVM
// backend will like.
if (Size == 128)
return ABIArgInfo::getDirect(llvm::VectorType::get(
llvm::Type::getInt64Ty(getVMContext()), 2));
// Always return in register if it fits in a general purpose
// register, or if it is 64 bits and has a single element.
if ((Size == 8 || Size == 16 || Size == 32) ||
(Size == 64 && VT->getNumElements() == 1))
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
Size));
return getIndirectReturnResult(RetTy, State);
}
return ABIArgInfo::getDirect();
}
if (isAggregateTypeForABI(RetTy)) {
if (const RecordType *RT = RetTy->getAs<RecordType>()) {
// Structures with flexible arrays are always indirect.
if (RT->getDecl()->hasFlexibleArrayMember())
return getIndirectReturnResult(RetTy, State);
}
// If specified, structs and unions are always indirect.
if (!IsRetSmallStructInRegABI && !RetTy->isAnyComplexType())
return getIndirectReturnResult(RetTy, State);
// Small structures which are register sized are generally returned
// in a register.
if (shouldReturnTypeInRegister(RetTy, getContext())) {
uint64_t Size = getContext().getTypeSize(RetTy);
// As a special-case, if the struct is a "single-element" struct, and
// the field is of type "float" or "double", return it in a
// floating-point register. (MSVC does not apply this special case.)
// We apply a similar transformation for pointer types to improve the
// quality of the generated IR.
if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
if ((!IsWin32StructABI && SeltTy->isRealFloatingType())
|| SeltTy->hasPointerRepresentation())
return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
// FIXME: We should be able to narrow this integer in cases with dead
// padding.
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),Size));
}
return getIndirectReturnResult(RetTy, State);
}
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
static bool isSSEVectorType(ASTContext &Context, QualType Ty) {
return Ty->getAs<VectorType>() && Context.getTypeSize(Ty) == 128;
}
static bool isRecordWithSSEVectorType(ASTContext &Context, QualType Ty) {
const RecordType *RT = Ty->getAs<RecordType>();
if (!RT)
return 0;
const RecordDecl *RD = RT->getDecl();
// If this is a C++ record, check the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
for (const auto &I : CXXRD->bases())
if (!isRecordWithSSEVectorType(Context, I.getType()))
return false;
for (const auto *i : RD->fields()) {
QualType FT = i->getType();
if (isSSEVectorType(Context, FT))
return true;
if (isRecordWithSSEVectorType(Context, FT))
return true;
}
return false;
}
unsigned X86_32ABIInfo::getTypeStackAlignInBytes(QualType Ty,
unsigned Align) const {
// Otherwise, if the alignment is less than or equal to the minimum ABI
// alignment, just use the default; the backend will handle this.
if (Align <= MinABIStackAlignInBytes)
return 0; // Use default alignment.
// On non-Darwin, the stack type alignment is always 4.
if (!IsDarwinVectorABI) {
// Set explicit alignment, since we may need to realign the top.
return MinABIStackAlignInBytes;
}
// Otherwise, if the type contains an SSE vector type, the alignment is 16.
if (Align >= 16 && (isSSEVectorType(getContext(), Ty) ||
isRecordWithSSEVectorType(getContext(), Ty)))
return 16;
return MinABIStackAlignInBytes;
}
ABIArgInfo X86_32ABIInfo::getIndirectResult(QualType Ty, bool ByVal,
CCState &State) const {
if (!ByVal) {
if (State.FreeRegs) {
--State.FreeRegs; // Non-byval indirects just use one pointer.
return getNaturalAlignIndirectInReg(Ty);
}
return getNaturalAlignIndirect(Ty, false);
}
// Compute the byval alignment.
unsigned TypeAlign = getContext().getTypeAlign(Ty) / 8;
unsigned StackAlign = getTypeStackAlignInBytes(Ty, TypeAlign);
if (StackAlign == 0)
return ABIArgInfo::getIndirect(CharUnits::fromQuantity(4), /*ByVal=*/true);
// If the stack alignment is less than the type alignment, realign the
// argument.
bool Realign = TypeAlign > StackAlign;
return ABIArgInfo::getIndirect(CharUnits::fromQuantity(StackAlign),
/*ByVal=*/true, Realign);
}
X86_32ABIInfo::Class X86_32ABIInfo::classify(QualType Ty) const {
const Type *T = isSingleElementStruct(Ty, getContext());
if (!T)
T = Ty.getTypePtr();
if (const BuiltinType *BT = T->getAs<BuiltinType>()) {
BuiltinType::Kind K = BT->getKind();
if (K == BuiltinType::Float || K == BuiltinType::Double)
return Float;
}
return Integer;
}
bool X86_32ABIInfo::shouldUseInReg(QualType Ty, CCState &State,
bool &NeedsPadding) const {
NeedsPadding = false;
if (!IsSoftFloatABI) {
Class C = classify(Ty);
if (C == Float)
return false;
}
unsigned Size = getContext().getTypeSize(Ty);
unsigned SizeInRegs = (Size + 31) / 32;
if (SizeInRegs == 0)
return false;
if (!IsMCUABI) {
if (SizeInRegs > State.FreeRegs) {
State.FreeRegs = 0;
return false;
}
} else {
// The MCU psABI allows passing parameters in-reg even if there are
// earlier parameters that are passed on the stack. Also,
// it does not allow passing >8-byte structs in-register,
// even if there are 3 free registers available.
if (SizeInRegs > State.FreeRegs || SizeInRegs > 2)
return false;
}
State.FreeRegs -= SizeInRegs;
if (State.CC == llvm::CallingConv::X86_FastCall ||
State.CC == llvm::CallingConv::X86_VectorCall) {
if (Size > 32)
return false;
if (Ty->isIntegralOrEnumerationType())
return true;
if (Ty->isPointerType())
return true;
if (Ty->isReferenceType())
return true;
if (State.FreeRegs)
NeedsPadding = true;
return false;
}
return true;
}
ABIArgInfo X86_32ABIInfo::classifyArgumentType(QualType Ty,
CCState &State) const {
// FIXME: Set alignment on indirect arguments.
Ty = useFirstFieldIfTransparentUnion(Ty);
// Check with the C++ ABI first.
const RecordType *RT = Ty->getAs<RecordType>();
if (RT) {
CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI());
if (RAA == CGCXXABI::RAA_Indirect) {
return getIndirectResult(Ty, false, State);
} else if (RAA == CGCXXABI::RAA_DirectInMemory) {
// The field index doesn't matter, we'll fix it up later.
return ABIArgInfo::getInAlloca(/*FieldIndex=*/0);
}
}
// vectorcall adds the concept of a homogenous vector aggregate, similar
// to other targets.
const Type *Base = nullptr;
uint64_t NumElts = 0;
if (State.CC == llvm::CallingConv::X86_VectorCall &&
isHomogeneousAggregate(Ty, Base, NumElts)) {
if (State.FreeSSERegs >= NumElts) {
State.FreeSSERegs -= NumElts;
if (Ty->isBuiltinType() || Ty->isVectorType())
return ABIArgInfo::getDirect();
return ABIArgInfo::getExpand();
}
return getIndirectResult(Ty, /*ByVal=*/false, State);
}
if (isAggregateTypeForABI(Ty)) {
if (RT) {
// Structs are always byval on win32, regardless of what they contain.
if (IsWin32StructABI)
return getIndirectResult(Ty, true, State);
// Structures with flexible arrays are always indirect.
if (RT->getDecl()->hasFlexibleArrayMember())
return getIndirectResult(Ty, true, State);
}
// Ignore empty structs/unions.
if (isEmptyRecord(getContext(), Ty, true))
return ABIArgInfo::getIgnore();
llvm::LLVMContext &LLVMContext = getVMContext();
llvm::IntegerType *Int32 = llvm::Type::getInt32Ty(LLVMContext);
bool NeedsPadding;
if (shouldUseInReg(Ty, State, NeedsPadding)) {
unsigned SizeInRegs = (getContext().getTypeSize(Ty) + 31) / 32;
SmallVector<llvm::Type*, 3> Elements(SizeInRegs, Int32);
llvm::Type *Result = llvm::StructType::get(LLVMContext, Elements);
return ABIArgInfo::getDirectInReg(Result);
}
llvm::IntegerType *PaddingType = NeedsPadding ? Int32 : nullptr;
// Expand small (<= 128-bit) record types when we know that the stack layout
// of those arguments will match the struct. This is important because the
// LLVM backend isn't smart enough to remove byval, which inhibits many
// optimizations.
if (getContext().getTypeSize(Ty) <= 4*32 &&
canExpandIndirectArgument(Ty, getContext()))
return ABIArgInfo::getExpandWithPadding(
State.CC == llvm::CallingConv::X86_FastCall ||
State.CC == llvm::CallingConv::X86_VectorCall,
PaddingType);
return getIndirectResult(Ty, true, State);
}
if (const VectorType *VT = Ty->getAs<VectorType>()) {
// On Darwin, some vectors are passed in memory, we handle this by passing
// it as an i8/i16/i32/i64.
if (IsDarwinVectorABI) {
uint64_t Size = getContext().getTypeSize(Ty);
if ((Size == 8 || Size == 16 || Size == 32) ||
(Size == 64 && VT->getNumElements() == 1))
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
Size));
}
if (IsX86_MMXType(CGT.ConvertType(Ty)))
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), 64));
return ABIArgInfo::getDirect();
}
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
bool NeedsPadding;
bool InReg = shouldUseInReg(Ty, State, NeedsPadding);
if (Ty->isPromotableIntegerType()) {
if (InReg)
return ABIArgInfo::getExtendInReg();
return ABIArgInfo::getExtend();
}
if (InReg)
return ABIArgInfo::getDirectInReg();
return ABIArgInfo::getDirect();
}
void X86_32ABIInfo::computeInfo(CGFunctionInfo &FI) const {
CCState State(FI.getCallingConvention());
if (State.CC == llvm::CallingConv::X86_FastCall)
State.FreeRegs = 2;
else if (State.CC == llvm::CallingConv::X86_VectorCall) {
State.FreeRegs = 2;
State.FreeSSERegs = 6;
} else if (FI.getHasRegParm())
State.FreeRegs = FI.getRegParm();
else if (IsMCUABI)
State.FreeRegs = 3;
else
State.FreeRegs = DefaultNumRegisterParameters;
if (!getCXXABI().classifyReturnType(FI)) {
FI.getReturnInfo() = classifyReturnType(FI.getReturnType(), State);
} else if (FI.getReturnInfo().isIndirect()) {
// The C++ ABI is not aware of register usage, so we have to check if the
// return value was sret and put it in a register ourselves if appropriate.
if (State.FreeRegs) {
--State.FreeRegs; // The sret parameter consumes a register.
FI.getReturnInfo().setInReg(true);
}
}
// The chain argument effectively gives us another free register.
if (FI.isChainCall())
++State.FreeRegs;
bool UsedInAlloca = false;
for (auto &I : FI.arguments()) {
I.info = classifyArgumentType(I.type, State);
UsedInAlloca |= (I.info.getKind() == ABIArgInfo::InAlloca);
}
// If we needed to use inalloca for any argument, do a second pass and rewrite
// all the memory arguments to use inalloca.
if (UsedInAlloca)
rewriteWithInAlloca(FI);
}
void
X86_32ABIInfo::addFieldToArgStruct(SmallVector<llvm::Type *, 6> &FrameFields,
CharUnits &StackOffset, ABIArgInfo &Info,
QualType Type) const {
// Arguments are always 4-byte-aligned.
CharUnits FieldAlign = CharUnits::fromQuantity(4);
assert(StackOffset.isMultipleOf(FieldAlign) && "unaligned inalloca struct");
Info = ABIArgInfo::getInAlloca(FrameFields.size());
FrameFields.push_back(CGT.ConvertTypeForMem(Type));
StackOffset += getContext().getTypeSizeInChars(Type);
// Insert padding bytes to respect alignment.
CharUnits FieldEnd = StackOffset;
StackOffset = FieldEnd.RoundUpToAlignment(FieldAlign);
if (StackOffset != FieldEnd) {
CharUnits NumBytes = StackOffset - FieldEnd;
llvm::Type *Ty = llvm::Type::getInt8Ty(getVMContext());
Ty = llvm::ArrayType::get(Ty, NumBytes.getQuantity());
FrameFields.push_back(Ty);
}
}
static bool isArgInAlloca(const ABIArgInfo &Info) {
// Leave ignored and inreg arguments alone.
switch (Info.getKind()) {
case ABIArgInfo::InAlloca:
return true;
case ABIArgInfo::Indirect:
assert(Info.getIndirectByVal());
return true;
case ABIArgInfo::Ignore:
return false;
case ABIArgInfo::Direct:
case ABIArgInfo::Extend:
case ABIArgInfo::Expand:
if (Info.getInReg())
return false;
return true;
}
llvm_unreachable("invalid enum");
}
void X86_32ABIInfo::rewriteWithInAlloca(CGFunctionInfo &FI) const {
assert(IsWin32StructABI && "inalloca only supported on win32");
// Build a packed struct type for all of the arguments in memory.
SmallVector<llvm::Type *, 6> FrameFields;
// The stack alignment is always 4.
CharUnits StackAlign = CharUnits::fromQuantity(4);
CharUnits StackOffset;
CGFunctionInfo::arg_iterator I = FI.arg_begin(), E = FI.arg_end();
// Put 'this' into the struct before 'sret', if necessary.
bool IsThisCall =
FI.getCallingConvention() == llvm::CallingConv::X86_ThisCall;
ABIArgInfo &Ret = FI.getReturnInfo();
if (Ret.isIndirect() && Ret.isSRetAfterThis() && !IsThisCall &&
isArgInAlloca(I->info)) {
addFieldToArgStruct(FrameFields, StackOffset, I->info, I->type);
++I;
}
// Put the sret parameter into the inalloca struct if it's in memory.
if (Ret.isIndirect() && !Ret.getInReg()) {
CanQualType PtrTy = getContext().getPointerType(FI.getReturnType());
addFieldToArgStruct(FrameFields, StackOffset, Ret, PtrTy);
// On Windows, the hidden sret parameter is always returned in eax.
Ret.setInAllocaSRet(IsWin32StructABI);
}
// Skip the 'this' parameter in ecx.
if (IsThisCall)
++I;
// Put arguments passed in memory into the struct.
for (; I != E; ++I) {
if (isArgInAlloca(I->info))
addFieldToArgStruct(FrameFields, StackOffset, I->info, I->type);
}
FI.setArgStruct(llvm::StructType::get(getVMContext(), FrameFields,
/*isPacked=*/true),
StackAlign);
}
Address X86_32ABIInfo::EmitVAArg(CodeGenFunction &CGF,
Address VAListAddr, QualType Ty) const {
auto TypeInfo = getContext().getTypeInfoInChars(Ty);
// x86-32 changes the alignment of certain arguments on the stack.
//
// Just messing with TypeInfo like this works because we never pass
// anything indirectly.
TypeInfo.second = CharUnits::fromQuantity(
getTypeStackAlignInBytes(Ty, TypeInfo.second.getQuantity()));
return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*Indirect*/ false,
TypeInfo, CharUnits::fromQuantity(4),
/*AllowHigherAlign*/ true);
}
bool X86_32TargetCodeGenInfo::isStructReturnInRegABI(
const llvm::Triple &Triple, const CodeGenOptions &Opts) {
assert(Triple.getArch() == llvm::Triple::x86);
switch (Opts.getStructReturnConvention()) {
case CodeGenOptions::SRCK_Default:
break;
case CodeGenOptions::SRCK_OnStack: // -fpcc-struct-return
return false;
case CodeGenOptions::SRCK_InRegs: // -freg-struct-return
return true;
}
if (Triple.isOSDarwin() || Triple.isOSIAMCU())
return true;
switch (Triple.getOS()) {
case llvm::Triple::DragonFly:
case llvm::Triple::FreeBSD:
case llvm::Triple::OpenBSD:
case llvm::Triple::Bitrig:
case llvm::Triple::Win32:
return true;
default:
return false;
}
}
void X86_32TargetCodeGenInfo::setTargetAttributes(const Decl *D,
llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const {
if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
if (FD->hasAttr<X86ForceAlignArgPointerAttr>()) {
// Get the LLVM function.
llvm::Function *Fn = cast<llvm::Function>(GV);
// Now add the 'alignstack' attribute with a value of 16.
llvm::AttrBuilder B;
B.addStackAlignmentAttr(16);
Fn->addAttributes(llvm::AttributeSet::FunctionIndex,
llvm::AttributeSet::get(CGM.getLLVMContext(),
llvm::AttributeSet::FunctionIndex,
B));
}
}
}
bool X86_32TargetCodeGenInfo::initDwarfEHRegSizeTable(
CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
CodeGen::CGBuilderTy &Builder = CGF.Builder;
llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
// 0-7 are the eight integer registers; the order is different
// on Darwin (for EH), but the range is the same.
// 8 is %eip.
AssignToArrayRange(Builder, Address, Four8, 0, 8);
if (CGF.CGM.getTarget().getTriple().isOSDarwin()) {
// 12-16 are st(0..4). Not sure why we stop at 4.
// These have size 16, which is sizeof(long double) on
// platforms with 8-byte alignment for that type.
llvm::Value *Sixteen8 = llvm::ConstantInt::get(CGF.Int8Ty, 16);
AssignToArrayRange(Builder, Address, Sixteen8, 12, 16);
} else {
// 9 is %eflags, which doesn't get a size on Darwin for some
// reason.
Builder.CreateAlignedStore(
Four8, Builder.CreateConstInBoundsGEP1_32(CGF.Int8Ty, Address, 9),
CharUnits::One());
// 11-16 are st(0..5). Not sure why we stop at 5.
// These have size 12, which is sizeof(long double) on
// platforms with 4-byte alignment for that type.
llvm::Value *Twelve8 = llvm::ConstantInt::get(CGF.Int8Ty, 12);
AssignToArrayRange(Builder, Address, Twelve8, 11, 16);
}
return false;
}
//===----------------------------------------------------------------------===//
// X86-64 ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
/// The AVX ABI level for X86 targets.
enum class X86AVXABILevel {
None,
AVX,
AVX512
};
/// \p returns the size in bits of the largest (native) vector for \p AVXLevel.
static unsigned getNativeVectorSizeForAVXABI(X86AVXABILevel AVXLevel) {
switch (AVXLevel) {
case X86AVXABILevel::AVX512:
return 512;
case X86AVXABILevel::AVX:
return 256;
case X86AVXABILevel::None:
return 128;
}
llvm_unreachable("Unknown AVXLevel");
}
/// X86_64ABIInfo - The X86_64 ABI information.
class X86_64ABIInfo : public ABIInfo {
enum Class {
Integer = 0,
SSE,
SSEUp,
X87,
X87Up,
ComplexX87,
NoClass,
Memory
};
/// merge - Implement the X86_64 ABI merging algorithm.
///
/// Merge an accumulating classification \arg Accum with a field
/// classification \arg Field.
///
/// \param Accum - The accumulating classification. This should
/// always be either NoClass or the result of a previous merge
/// call. In addition, this should never be Memory (the caller
/// should just return Memory for the aggregate).
static Class merge(Class Accum, Class Field);
/// postMerge - Implement the X86_64 ABI post merging algorithm.
///
/// Post merger cleanup, reduces a malformed Hi and Lo pair to
/// final MEMORY or SSE classes when necessary.
///
/// \param AggregateSize - The size of the current aggregate in
/// the classification process.
///
/// \param Lo - The classification for the parts of the type
/// residing in the low word of the containing object.
///
/// \param Hi - The classification for the parts of the type
/// residing in the higher words of the containing object.
///
void postMerge(unsigned AggregateSize, Class &Lo, Class &Hi) const;
/// classify - Determine the x86_64 register classes in which the
/// given type T should be passed.
///
/// \param Lo - The classification for the parts of the type
/// residing in the low word of the containing object.
///
/// \param Hi - The classification for the parts of the type
/// residing in the high word of the containing object.
///
/// \param OffsetBase - The bit offset of this type in the
/// containing object. Some parameters are classified different
/// depending on whether they straddle an eightbyte boundary.
///
/// \param isNamedArg - Whether the argument in question is a "named"
/// argument, as used in AMD64-ABI 3.5.7.
///
/// If a word is unused its result will be NoClass; if a type should
/// be passed in Memory then at least the classification of \arg Lo
/// will be Memory.
///
/// The \arg Lo class will be NoClass iff the argument is ignored.
///
/// If the \arg Lo class is ComplexX87, then the \arg Hi class will
/// also be ComplexX87.
void classify(QualType T, uint64_t OffsetBase, Class &Lo, Class &Hi,
bool isNamedArg) const;
llvm::Type *GetByteVectorType(QualType Ty) const;
llvm::Type *GetSSETypeAtOffset(llvm::Type *IRType,
unsigned IROffset, QualType SourceTy,
unsigned SourceOffset) const;
llvm::Type *GetINTEGERTypeAtOffset(llvm::Type *IRType,
unsigned IROffset, QualType SourceTy,
unsigned SourceOffset) const;
/// getIndirectResult - Give a source type \arg Ty, return a suitable result
/// such that the argument will be returned in memory.
ABIArgInfo getIndirectReturnResult(QualType Ty) const;
/// getIndirectResult - Give a source type \arg Ty, return a suitable result
/// such that the argument will be passed in memory.
///
/// \param freeIntRegs - The number of free integer registers remaining
/// available.
ABIArgInfo getIndirectResult(QualType Ty, unsigned freeIntRegs) const;
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType Ty,
unsigned freeIntRegs,
unsigned &neededInt,
unsigned &neededSSE,
bool isNamedArg) const;
bool IsIllegalVectorType(QualType Ty) const;
/// The 0.98 ABI revision clarified a lot of ambiguities,
/// unfortunately in ways that were not always consistent with
/// certain previous compilers. In particular, platforms which
/// required strict binary compatibility with older versions of GCC
/// may need to exempt themselves.
bool honorsRevision0_98() const {
return !getTarget().getTriple().isOSDarwin();
}
X86AVXABILevel AVXLevel;
// Some ABIs (e.g. X32 ABI and Native Client OS) use 32 bit pointers on
// 64-bit hardware.
bool Has64BitPointers;
public:
X86_64ABIInfo(CodeGen::CodeGenTypes &CGT, X86AVXABILevel AVXLevel) :
ABIInfo(CGT), AVXLevel(AVXLevel),
Has64BitPointers(CGT.getDataLayout().getPointerSize(0) == 8) {
}
bool isPassedUsingAVXType(QualType type) const {
unsigned neededInt, neededSSE;
// The freeIntRegs argument doesn't matter here.
ABIArgInfo info = classifyArgumentType(type, 0, neededInt, neededSSE,
/*isNamedArg*/true);
if (info.isDirect()) {
llvm::Type *ty = info.getCoerceToType();
if (llvm::VectorType *vectorTy = dyn_cast_or_null<llvm::VectorType>(ty))
return (vectorTy->getBitWidth() > 128);
}
return false;
}
void computeInfo(CGFunctionInfo &FI) const override;
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
Address EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
bool has64BitPointers() const {
return Has64BitPointers;
}
};
/// WinX86_64ABIInfo - The Windows X86_64 ABI information.
class WinX86_64ABIInfo : public ABIInfo {
public:
WinX86_64ABIInfo(CodeGen::CodeGenTypes &CGT)
: ABIInfo(CGT),
IsMingw64(getTarget().getTriple().isWindowsGNUEnvironment()) {}
void computeInfo(CGFunctionInfo &FI) const override;
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
bool isHomogeneousAggregateBaseType(QualType Ty) const override {
// FIXME: Assumes vectorcall is in use.
return isX86VectorTypeForVectorCall(getContext(), Ty);
}
bool isHomogeneousAggregateSmallEnough(const Type *Ty,
uint64_t NumMembers) const override {
// FIXME: Assumes vectorcall is in use.
return isX86VectorCallAggregateSmallEnough(NumMembers);
}
private:
ABIArgInfo classify(QualType Ty, unsigned &FreeSSERegs,
bool IsReturnType) const;
bool IsMingw64;
};
class X86_64TargetCodeGenInfo : public TargetCodeGenInfo {
public:
X86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, X86AVXABILevel AVXLevel)
: TargetCodeGenInfo(new X86_64ABIInfo(CGT, AVXLevel)) {}
const X86_64ABIInfo &getABIInfo() const {
return static_cast<const X86_64ABIInfo&>(TargetCodeGenInfo::getABIInfo());
}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
return 7;
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const override {
llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
// 0-15 are the 16 integer registers.
// 16 is %rip.
AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
return false;
}
llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
StringRef Constraint,
llvm::Type* Ty) const override {
return X86AdjustInlineAsmType(CGF, Constraint, Ty);
}
bool isNoProtoCallVariadic(const CallArgList &args,
const FunctionNoProtoType *fnType) const override {
// The default CC on x86-64 sets %al to the number of SSA
// registers used, and GCC sets this when calling an unprototyped
// function, so we override the default behavior. However, don't do
// that when AVX types are involved: the ABI explicitly states it is
// undefined, and it doesn't work in practice because of how the ABI
// defines varargs anyway.
if (fnType->getCallConv() == CC_C) {
bool HasAVXType = false;
for (CallArgList::const_iterator
it = args.begin(), ie = args.end(); it != ie; ++it) {
if (getABIInfo().isPassedUsingAVXType(it->Ty)) {
HasAVXType = true;
break;
}
}
if (!HasAVXType)
return true;
}
return TargetCodeGenInfo::isNoProtoCallVariadic(args, fnType);
}
llvm::Constant *
getUBSanFunctionSignature(CodeGen::CodeGenModule &CGM) const override {
unsigned Sig;
if (getABIInfo().has64BitPointers())
Sig = (0xeb << 0) | // jmp rel8
(0x0a << 8) | // .+0x0c
('F' << 16) |
('T' << 24);
else
Sig = (0xeb << 0) | // jmp rel8
(0x06 << 8) | // .+0x08
('F' << 16) |
('T' << 24);
return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
}
};
class PS4TargetCodeGenInfo : public X86_64TargetCodeGenInfo {
public:
PS4TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, X86AVXABILevel AVXLevel)
: X86_64TargetCodeGenInfo(CGT, AVXLevel) {}
void getDependentLibraryOption(llvm::StringRef Lib,
llvm::SmallString<24> &Opt) const override {
Opt = "\01";
// If the argument contains a space, enclose it in quotes.
if (Lib.find(" ") != StringRef::npos)
Opt += "\"" + Lib.str() + "\"";
else
Opt += Lib;
}
};
static std::string qualifyWindowsLibrary(llvm::StringRef Lib) {
// If the argument does not end in .lib, automatically add the suffix.
// If the argument contains a space, enclose it in quotes.
// This matches the behavior of MSVC.
bool Quote = (Lib.find(" ") != StringRef::npos);
std::string ArgStr = Quote ? "\"" : "";
ArgStr += Lib;
if (!Lib.endswith_lower(".lib"))
ArgStr += ".lib";
ArgStr += Quote ? "\"" : "";
return ArgStr;
}
class WinX86_32TargetCodeGenInfo : public X86_32TargetCodeGenInfo {
public:
WinX86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
bool DarwinVectorABI, bool RetSmallStructInRegABI, bool Win32StructABI,
unsigned NumRegisterParameters)
: X86_32TargetCodeGenInfo(CGT, DarwinVectorABI, RetSmallStructInRegABI,
Win32StructABI, NumRegisterParameters, false) {}
void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const override;
void getDependentLibraryOption(llvm::StringRef Lib,
llvm::SmallString<24> &Opt) const override {
Opt = "/DEFAULTLIB:";
Opt += qualifyWindowsLibrary(Lib);
}
void getDetectMismatchOption(llvm::StringRef Name,
llvm::StringRef Value,
llvm::SmallString<32> &Opt) const override {
Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
}
};
static void addStackProbeSizeTargetAttribute(const Decl *D,
llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) {
if (D && isa<FunctionDecl>(D)) {
if (CGM.getCodeGenOpts().StackProbeSize != 4096) {
llvm::Function *Fn = cast<llvm::Function>(GV);
Fn->addFnAttr("stack-probe-size",
llvm::utostr(CGM.getCodeGenOpts().StackProbeSize));
}
}
}
void WinX86_32TargetCodeGenInfo::setTargetAttributes(const Decl *D,
llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const {
X86_32TargetCodeGenInfo::setTargetAttributes(D, GV, CGM);
addStackProbeSizeTargetAttribute(D, GV, CGM);
}
class WinX86_64TargetCodeGenInfo : public TargetCodeGenInfo {
public:
WinX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
X86AVXABILevel AVXLevel)
: TargetCodeGenInfo(new WinX86_64ABIInfo(CGT)) {}
void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const override;
int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
return 7;
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const override {
llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
// 0-15 are the 16 integer registers.
// 16 is %rip.
AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
return false;
}
void getDependentLibraryOption(llvm::StringRef Lib,
llvm::SmallString<24> &Opt) const override {
Opt = "/DEFAULTLIB:";
Opt += qualifyWindowsLibrary(Lib);
}
void getDetectMismatchOption(llvm::StringRef Name,
llvm::StringRef Value,
llvm::SmallString<32> &Opt) const override {
Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
}
};
void WinX86_64TargetCodeGenInfo::setTargetAttributes(const Decl *D,
llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const {
TargetCodeGenInfo::setTargetAttributes(D, GV, CGM);
addStackProbeSizeTargetAttribute(D, GV, CGM);
}
}
void X86_64ABIInfo::postMerge(unsigned AggregateSize, Class &Lo,
Class &Hi) const {
// AMD64-ABI 3.2.3p2: Rule 5. Then a post merger cleanup is done:
//
// (a) If one of the classes is Memory, the whole argument is passed in
// memory.
//
// (b) If X87UP is not preceded by X87, the whole argument is passed in
// memory.
//
// (c) If the size of the aggregate exceeds two eightbytes and the first
// eightbyte isn't SSE or any other eightbyte isn't SSEUP, the whole
// argument is passed in memory. NOTE: This is necessary to keep the
// ABI working for processors that don't support the __m256 type.
//
// (d) If SSEUP is not preceded by SSE or SSEUP, it is converted to SSE.
//
// Some of these are enforced by the merging logic. Others can arise
// only with unions; for example:
// union { _Complex double; unsigned; }
//
// Note that clauses (b) and (c) were added in 0.98.
//
if (Hi == Memory)
Lo = Memory;
if (Hi == X87Up && Lo != X87 && honorsRevision0_98())
Lo = Memory;
if (AggregateSize > 128 && (Lo != SSE || Hi != SSEUp))
Lo = Memory;
if (Hi == SSEUp && Lo != SSE)
Hi = SSE;
}
X86_64ABIInfo::Class X86_64ABIInfo::merge(Class Accum, Class Field) {
// AMD64-ABI 3.2.3p2: Rule 4. Each field of an object is
// classified recursively so that always two fields are
// considered. The resulting class is calculated according to
// the classes of the fields in the eightbyte:
//
// (a) If both classes are equal, this is the resulting class.
//
// (b) If one of the classes is NO_CLASS, the resulting class is
// the other class.
//
// (c) If one of the classes is MEMORY, the result is the MEMORY
// class.
//
// (d) If one of the classes is INTEGER, the result is the
// INTEGER.
//
// (e) If one of the classes is X87, X87UP, COMPLEX_X87 class,
// MEMORY is used as class.
//
// (f) Otherwise class SSE is used.
// Accum should never be memory (we should have returned) or
// ComplexX87 (because this cannot be passed in a structure).
assert((Accum != Memory && Accum != ComplexX87) &&
"Invalid accumulated classification during merge.");
if (Accum == Field || Field == NoClass)
return Accum;
if (Field == Memory)
return Memory;
if (Accum == NoClass)
return Field;
if (Accum == Integer || Field == Integer)
return Integer;
if (Field == X87 || Field == X87Up || Field == ComplexX87 ||
Accum == X87 || Accum == X87Up)
return Memory;
return SSE;
}
void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase,
Class &Lo, Class &Hi, bool isNamedArg) const {
// FIXME: This code can be simplified by introducing a simple value class for
// Class pairs with appropriate constructor methods for the various
// situations.
// FIXME: Some of the split computations are wrong; unaligned vectors
// shouldn't be passed in registers for example, so there is no chance they
// can straddle an eightbyte. Verify & simplify.
Lo = Hi = NoClass;
Class &Current = OffsetBase < 64 ? Lo : Hi;
Current = Memory;
if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
BuiltinType::Kind k = BT->getKind();
if (k == BuiltinType::Void) {
Current = NoClass;
} else if (k == BuiltinType::Int128 || k == BuiltinType::UInt128) {
Lo = Integer;
Hi = Integer;
} else if (k >= BuiltinType::Bool && k <= BuiltinType::LongLong) {
Current = Integer;
} else if (k == BuiltinType::Float || k == BuiltinType::Double) {
Current = SSE;
} else if (k == BuiltinType::LongDouble) {
const llvm::fltSemantics *LDF = &getTarget().getLongDoubleFormat();
if (LDF == &llvm::APFloat::IEEEquad) {
Lo = SSE;
Hi = SSEUp;
} else if (LDF == &llvm::APFloat::x87DoubleExtended) {
Lo = X87;
Hi = X87Up;
} else if (LDF == &llvm::APFloat::IEEEdouble) {
Current = SSE;
} else
llvm_unreachable("unexpected long double representation!");
}
// FIXME: _Decimal32 and _Decimal64 are SSE.
// FIXME: _float128 and _Decimal128 are (SSE, SSEUp).
return;
}
if (const EnumType *ET = Ty->getAs<EnumType>()) {
// Classify the underlying integer type.
classify(ET->getDecl()->getIntegerType(), OffsetBase, Lo, Hi, isNamedArg);
return;
}
if (Ty->hasPointerRepresentation()) {
Current = Integer;
return;
}
if (Ty->isMemberPointerType()) {
if (Ty->isMemberFunctionPointerType()) {
if (Has64BitPointers) {
// If Has64BitPointers, this is an {i64, i64}, so classify both
// Lo and Hi now.
Lo = Hi = Integer;
} else {
// Otherwise, with 32-bit pointers, this is an {i32, i32}. If that
// straddles an eightbyte boundary, Hi should be classified as well.
uint64_t EB_FuncPtr = (OffsetBase) / 64;
uint64_t EB_ThisAdj = (OffsetBase + 64 - 1) / 64;
if (EB_FuncPtr != EB_ThisAdj) {
Lo = Hi = Integer;
} else {
Current = Integer;
}
}
} else {
Current = Integer;
}
return;
}
if (const VectorType *VT = Ty->getAs<VectorType>()) {
uint64_t Size = getContext().getTypeSize(VT);
if (Size == 1 || Size == 8 || Size == 16 || Size == 32) {
// gcc passes the following as integer:
// 4 bytes - <4 x char>, <2 x short>, <1 x int>, <1 x float>
// 2 bytes - <2 x char>, <1 x short>
// 1 byte - <1 x char>
Current = Integer;
// If this type crosses an eightbyte boundary, it should be
// split.
uint64_t EB_Lo = (OffsetBase) / 64;
uint64_t EB_Hi = (OffsetBase + Size - 1) / 64;
if (EB_Lo != EB_Hi)
Hi = Lo;
} else if (Size == 64) {
// gcc passes <1 x double> in memory. :(
if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::Double))
return;
// gcc passes <1 x long long> as INTEGER.
if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::LongLong) ||
VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULongLong) ||
VT->getElementType()->isSpecificBuiltinType(BuiltinType::Long) ||
VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULong))
Current = Integer;
else
Current = SSE;
// If this type crosses an eightbyte boundary, it should be
// split.
if (OffsetBase && OffsetBase != 64)
Hi = Lo;
} else if (Size == 128 ||
(isNamedArg && Size <= getNativeVectorSizeForAVXABI(AVXLevel))) {
// Arguments of 256-bits are split into four eightbyte chunks. The
// least significant one belongs to class SSE and all the others to class
// SSEUP. The original Lo and Hi design considers that types can't be
// greater than 128-bits, so a 64-bit split in Hi and Lo makes sense.
// This design isn't correct for 256-bits, but since there're no cases
// where the upper parts would need to be inspected, avoid adding
// complexity and just consider Hi to match the 64-256 part.
//
// Note that per 3.5.7 of AMD64-ABI, 256-bit args are only passed in
// registers if they are "named", i.e. not part of the "..." of a
// variadic function.
//
// Similarly, per 3.2.3. of the AVX512 draft, 512-bits ("named") args are
// split into eight eightbyte chunks, one SSE and seven SSEUP.
Lo = SSE;
Hi = SSEUp;
}
return;
}
if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
QualType ET = getContext().getCanonicalType(CT->getElementType());
uint64_t Size = getContext().getTypeSize(Ty);
if (ET->isIntegralOrEnumerationType()) {
if (Size <= 64)
Current = Integer;
else if (Size <= 128)
Lo = Hi = Integer;
} else if (ET == getContext().FloatTy) {
Current = SSE;
} else if (ET == getContext().DoubleTy) {
Lo = Hi = SSE;
} else if (ET == getContext().LongDoubleTy) {
const llvm::fltSemantics *LDF = &getTarget().getLongDoubleFormat();
if (LDF == &llvm::APFloat::IEEEquad)
Current = Memory;
else if (LDF == &llvm::APFloat::x87DoubleExtended)
Current = ComplexX87;
else if (LDF == &llvm::APFloat::IEEEdouble)
Lo = Hi = SSE;
else
llvm_unreachable("unexpected long double representation!");
}
// If this complex type crosses an eightbyte boundary then it
// should be split.
uint64_t EB_Real = (OffsetBase) / 64;
uint64_t EB_Imag = (OffsetBase + getContext().getTypeSize(ET)) / 64;
if (Hi == NoClass && EB_Real != EB_Imag)
Hi = Lo;
return;
}
if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
// Arrays are treated like structures.
uint64_t Size = getContext().getTypeSize(Ty);
// AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
// than four eightbytes, ..., it has class MEMORY.
if (Size > 256)
return;
// AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned
// fields, it has class MEMORY.
//
// Only need to check alignment of array base.
if (OffsetBase % getContext().getTypeAlign(AT->getElementType()))
return;
// Otherwise implement simplified merge. We could be smarter about
// this, but it isn't worth it and would be harder to verify.
Current = NoClass;
uint64_t EltSize = getContext().getTypeSize(AT->getElementType());
uint64_t ArraySize = AT->getSize().getZExtValue();
// The only case a 256-bit wide vector could be used is when the array
// contains a single 256-bit element. Since Lo and Hi logic isn't extended
// to work for sizes wider than 128, early check and fallback to memory.
if (Size > 128 && EltSize != 256)
return;
for (uint64_t i=0, Offset=OffsetBase; i<ArraySize; ++i, Offset += EltSize) {
Class FieldLo, FieldHi;
classify(AT->getElementType(), Offset, FieldLo, FieldHi, isNamedArg);
Lo = merge(Lo, FieldLo);
Hi = merge(Hi, FieldHi);
if (Lo == Memory || Hi == Memory)
break;
}
postMerge(Size, Lo, Hi);
assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp array classification.");
return;
}
if (const RecordType *RT = Ty->getAs<RecordType>()) {
uint64_t Size = getContext().getTypeSize(Ty);
// AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
// than four eightbytes, ..., it has class MEMORY.
if (Size > 256)
return;
// AMD64-ABI 3.2.3p2: Rule 2. If a C++ object has either a non-trivial
// copy constructor or a non-trivial destructor, it is passed by invisible
// reference.
if (getRecordArgABI(RT, getCXXABI()))
return;
const RecordDecl *RD = RT->getDecl();
// Assume variable sized types are passed in memory.
if (RD->hasFlexibleArrayMember())
return;
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
// Reset Lo class, this will be recomputed.
Current = NoClass;
// If this is a C++ record, classify the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
for (const auto &I : CXXRD->bases()) {
assert(!I.isVirtual() && !I.getType()->isDependentType() &&
"Unexpected base class!");
const CXXRecordDecl *Base =
cast<CXXRecordDecl>(I.getType()->getAs<RecordType>()->getDecl());
// Classify this field.
//
// AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate exceeds a
// single eightbyte, each is classified separately. Each eightbyte gets
// initialized to class NO_CLASS.
Class FieldLo, FieldHi;
uint64_t Offset =
OffsetBase + getContext().toBits(Layout.getBaseClassOffset(Base));
classify(I.getType(), Offset, FieldLo, FieldHi, isNamedArg);
Lo = merge(Lo, FieldLo);
Hi = merge(Hi, FieldHi);
if (Lo == Memory || Hi == Memory) {
postMerge(Size, Lo, Hi);
return;
}
}
}
// Classify the fields one at a time, merging the results.
unsigned idx = 0;
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i, ++idx) {
uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
bool BitField = i->isBitField();
// AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger than
// four eightbytes, or it contains unaligned fields, it has class MEMORY.
//
// The only case a 256-bit wide vector could be used is when the struct
// contains a single 256-bit element. Since Lo and Hi logic isn't extended
// to work for sizes wider than 128, early check and fallback to memory.
//
if (Size > 128 && getContext().getTypeSize(i->getType()) != 256) {
Lo = Memory;
postMerge(Size, Lo, Hi);
return;
}
// Note, skip this test for bit-fields, see below.
if (!BitField && Offset % getContext().getTypeAlign(i->getType())) {
Lo = Memory;
postMerge(Size, Lo, Hi);
return;
}
// Classify this field.
//
// AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate
// exceeds a single eightbyte, each is classified
// separately. Each eightbyte gets initialized to class
// NO_CLASS.
Class FieldLo, FieldHi;
// Bit-fields require special handling, they do not force the
// structure to be passed in memory even if unaligned, and
// therefore they can straddle an eightbyte.
if (BitField) {
// Ignore padding bit-fields.
if (i->isUnnamedBitfield())
continue;
uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
uint64_t Size = i->getBitWidthValue(getContext());
uint64_t EB_Lo = Offset / 64;
uint64_t EB_Hi = (Offset + Size - 1) / 64;
if (EB_Lo) {
assert(EB_Hi == EB_Lo && "Invalid classification, type > 16 bytes.");
FieldLo = NoClass;
FieldHi = Integer;
} else {
FieldLo = Integer;
FieldHi = EB_Hi ? Integer : NoClass;
}
} else
classify(i->getType(), Offset, FieldLo, FieldHi, isNamedArg);
Lo = merge(Lo, FieldLo);
Hi = merge(Hi, FieldHi);
if (Lo == Memory || Hi == Memory)
break;
}
postMerge(Size, Lo, Hi);
}
}
ABIArgInfo X86_64ABIInfo::getIndirectReturnResult(QualType Ty) const {
// If this is a scalar LLVM value then assume LLVM will pass it in the right
// place naturally.
if (!isAggregateTypeForABI(Ty)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
return getNaturalAlignIndirect(Ty);
}
bool X86_64ABIInfo::IsIllegalVectorType(QualType Ty) const {
if (const VectorType *VecTy = Ty->getAs<VectorType>()) {
uint64_t Size = getContext().getTypeSize(VecTy);
unsigned LargestVector = getNativeVectorSizeForAVXABI(AVXLevel);
if (Size <= 64 || Size > LargestVector)
return true;
}
return false;
}
ABIArgInfo X86_64ABIInfo::getIndirectResult(QualType Ty,
unsigned freeIntRegs) const {
// If this is a scalar LLVM value then assume LLVM will pass it in the right
// place naturally.
//
// This assumption is optimistic, as there could be free registers available
// when we need to pass this argument in memory, and LLVM could try to pass
// the argument in the free register. This does not seem to happen currently,
// but this code would be much safer if we could mark the argument with
// 'onstack'. See PR12193.
if (!isAggregateTypeForABI(Ty) && !IsIllegalVectorType(Ty)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
// Compute the byval alignment. We specify the alignment of the byval in all
// cases so that the mid-level optimizer knows the alignment of the byval.
unsigned Align = std::max(getContext().getTypeAlign(Ty) / 8, 8U);
// Attempt to avoid passing indirect results using byval when possible. This
// is important for good codegen.
//
// We do this by coercing the value into a scalar type which the backend can
// handle naturally (i.e., without using byval).
//
// For simplicity, we currently only do this when we have exhausted all of the
// free integer registers. Doing this when there are free integer registers
// would require more care, as we would have to ensure that the coerced value
// did not claim the unused register. That would require either reording the
// arguments to the function (so that any subsequent inreg values came first),
// or only doing this optimization when there were no following arguments that
// might be inreg.
//
// We currently expect it to be rare (particularly in well written code) for
// arguments to be passed on the stack when there are still free integer
// registers available (this would typically imply large structs being passed
// by value), so this seems like a fair tradeoff for now.
//
// We can revisit this if the backend grows support for 'onstack' parameter
// attributes. See PR12193.
if (freeIntRegs == 0) {
uint64_t Size = getContext().getTypeSize(Ty);
// If this type fits in an eightbyte, coerce it into the matching integral
// type, which will end up on the stack (with alignment 8).
if (Align == 8 && Size <= 64)
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
Size));
}
return ABIArgInfo::getIndirect(CharUnits::fromQuantity(Align));
}
/// The ABI specifies that a value should be passed in a full vector XMM/YMM
/// register. Pick an LLVM IR type that will be passed as a vector register.
llvm::Type *X86_64ABIInfo::GetByteVectorType(QualType Ty) const {
// Wrapper structs/arrays that only contain vectors are passed just like
// vectors; strip them off if present.
if (const Type *InnerTy = isSingleElementStruct(Ty, getContext()))
Ty = QualType(InnerTy, 0);
llvm::Type *IRType = CGT.ConvertType(Ty);
if (isa<llvm::VectorType>(IRType) ||
IRType->getTypeID() == llvm::Type::FP128TyID)
return IRType;
// We couldn't find the preferred IR vector type for 'Ty'.
uint64_t Size = getContext().getTypeSize(Ty);
assert((Size == 128 || Size == 256) && "Invalid type found!");
// Return a LLVM IR vector type based on the size of 'Ty'.
return llvm::VectorType::get(llvm::Type::getDoubleTy(getVMContext()),
Size / 64);
}
/// BitsContainNoUserData - Return true if the specified [start,end) bit range
/// is known to either be off the end of the specified type or being in
/// alignment padding. The user type specified is known to be at most 128 bits
/// in size, and have passed through X86_64ABIInfo::classify with a successful
/// classification that put one of the two halves in the INTEGER class.
///
/// It is conservatively correct to return false.
static bool BitsContainNoUserData(QualType Ty, unsigned StartBit,
unsigned EndBit, ASTContext &Context) {
// If the bytes being queried are off the end of the type, there is no user
// data hiding here. This handles analysis of builtins, vectors and other
// types that don't contain interesting padding.
unsigned TySize = (unsigned)Context.getTypeSize(Ty);
if (TySize <= StartBit)
return true;
if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
unsigned EltSize = (unsigned)Context.getTypeSize(AT->getElementType());
unsigned NumElts = (unsigned)AT->getSize().getZExtValue();
// Check each element to see if the element overlaps with the queried range.
for (unsigned i = 0; i != NumElts; ++i) {
// If the element is after the span we care about, then we're done..
unsigned EltOffset = i*EltSize;
if (EltOffset >= EndBit) break;
unsigned EltStart = EltOffset < StartBit ? StartBit-EltOffset :0;
if (!BitsContainNoUserData(AT->getElementType(), EltStart,
EndBit-EltOffset, Context))
return false;
}
// If it overlaps no elements, then it is safe to process as padding.
return true;
}
if (const RecordType *RT = Ty->getAs<RecordType>()) {
const RecordDecl *RD = RT->getDecl();
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
// If this is a C++ record, check the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
for (const auto &I : CXXRD->bases()) {
assert(!I.isVirtual() && !I.getType()->isDependentType() &&
"Unexpected base class!");
const CXXRecordDecl *Base =
cast<CXXRecordDecl>(I.getType()->getAs<RecordType>()->getDecl());
// If the base is after the span we care about, ignore it.
unsigned BaseOffset = Context.toBits(Layout.getBaseClassOffset(Base));
if (BaseOffset >= EndBit) continue;
unsigned BaseStart = BaseOffset < StartBit ? StartBit-BaseOffset :0;
if (!BitsContainNoUserData(I.getType(), BaseStart,
EndBit-BaseOffset, Context))
return false;
}
}
// Verify that no field has data that overlaps the region of interest. Yes
// this could be sped up a lot by being smarter about queried fields,
// however we're only looking at structs up to 16 bytes, so we don't care
// much.
unsigned idx = 0;
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i, ++idx) {
unsigned FieldOffset = (unsigned)Layout.getFieldOffset(idx);
// If we found a field after the region we care about, then we're done.
if (FieldOffset >= EndBit) break;
unsigned FieldStart = FieldOffset < StartBit ? StartBit-FieldOffset :0;
if (!BitsContainNoUserData(i->getType(), FieldStart, EndBit-FieldOffset,
Context))
return false;
}
// If nothing in this record overlapped the area of interest, then we're
// clean.
return true;
}
return false;
}
/// ContainsFloatAtOffset - Return true if the specified LLVM IR type has a
/// float member at the specified offset. For example, {int,{float}} has a
/// float at offset 4. It is conservatively correct for this routine to return
/// false.
static bool ContainsFloatAtOffset(llvm::Type *IRType, unsigned IROffset,
const llvm::DataLayout &TD) {
// Base case if we find a float.
if (IROffset == 0 && IRType->isFloatTy())
return true;
// If this is a struct, recurse into the field at the specified offset.
if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
const llvm::StructLayout *SL = TD.getStructLayout(STy);
unsigned Elt = SL->getElementContainingOffset(IROffset);
IROffset -= SL->getElementOffset(Elt);
return ContainsFloatAtOffset(STy->getElementType(Elt), IROffset, TD);
}
// If this is an array, recurse into the field at the specified offset.
if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
llvm::Type *EltTy = ATy->getElementType();
unsigned EltSize = TD.getTypeAllocSize(EltTy);
IROffset -= IROffset/EltSize*EltSize;
return ContainsFloatAtOffset(EltTy, IROffset, TD);
}
return false;
}
/// GetSSETypeAtOffset - Return a type that will be passed by the backend in the
/// low 8 bytes of an XMM register, corresponding to the SSE class.
llvm::Type *X86_64ABIInfo::
GetSSETypeAtOffset(llvm::Type *IRType, unsigned IROffset,
QualType SourceTy, unsigned SourceOffset) const {
// The only three choices we have are either double, <2 x float>, or float. We
// pass as float if the last 4 bytes is just padding. This happens for
// structs that contain 3 floats.
if (BitsContainNoUserData(SourceTy, SourceOffset*8+32,
SourceOffset*8+64, getContext()))
return llvm::Type::getFloatTy(getVMContext());
// We want to pass as <2 x float> if the LLVM IR type contains a float at
// offset+0 and offset+4. Walk the LLVM IR type to find out if this is the
// case.
if (ContainsFloatAtOffset(IRType, IROffset, getDataLayout()) &&
ContainsFloatAtOffset(IRType, IROffset+4, getDataLayout()))
return llvm::VectorType::get(llvm::Type::getFloatTy(getVMContext()), 2);
return llvm::Type::getDoubleTy(getVMContext());
}
/// GetINTEGERTypeAtOffset - The ABI specifies that a value should be passed in
/// an 8-byte GPR. This means that we either have a scalar or we are talking
/// about the high or low part of an up-to-16-byte struct. This routine picks
/// the best LLVM IR type to represent this, which may be i64 or may be anything
/// else that the backend will pass in a GPR that works better (e.g. i8, %foo*,
/// etc).
///
/// PrefType is an LLVM IR type that corresponds to (part of) the IR type for
/// the source type. IROffset is an offset in bytes into the LLVM IR type that
/// the 8-byte value references. PrefType may be null.
///
/// SourceTy is the source-level type for the entire argument. SourceOffset is
/// an offset into this that we're processing (which is always either 0 or 8).
///
llvm::Type *X86_64ABIInfo::
GetINTEGERTypeAtOffset(llvm::Type *IRType, unsigned IROffset,
QualType SourceTy, unsigned SourceOffset) const {
// If we're dealing with an un-offset LLVM IR type, then it means that we're
// returning an 8-byte unit starting with it. See if we can safely use it.
if (IROffset == 0) {
// Pointers and int64's always fill the 8-byte unit.
if ((isa<llvm::PointerType>(IRType) && Has64BitPointers) ||
IRType->isIntegerTy(64))
return IRType;
// If we have a 1/2/4-byte integer, we can use it only if the rest of the
// goodness in the source type is just tail padding. This is allowed to
// kick in for struct {double,int} on the int, but not on
// struct{double,int,int} because we wouldn't return the second int. We
// have to do this analysis on the source type because we can't depend on
// unions being lowered a specific way etc.
if (IRType->isIntegerTy(8) || IRType->isIntegerTy(16) ||
IRType->isIntegerTy(32) ||
(isa<llvm::PointerType>(IRType) && !Has64BitPointers)) {
unsigned BitWidth = isa<llvm::PointerType>(IRType) ? 32 :
cast<llvm::IntegerType>(IRType)->getBitWidth();
if (BitsContainNoUserData(SourceTy, SourceOffset*8+BitWidth,
SourceOffset*8+64, getContext()))
return IRType;
}
}
if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
// If this is a struct, recurse into the field at the specified offset.
const llvm::StructLayout *SL = getDataLayout().getStructLayout(STy);
if (IROffset < SL->getSizeInBytes()) {
unsigned FieldIdx = SL->getElementContainingOffset(IROffset);
IROffset -= SL->getElementOffset(FieldIdx);
return GetINTEGERTypeAtOffset(STy->getElementType(FieldIdx), IROffset,
SourceTy, SourceOffset);
}
}
if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
llvm::Type *EltTy = ATy->getElementType();
unsigned EltSize = getDataLayout().getTypeAllocSize(EltTy);
unsigned EltOffset = IROffset/EltSize*EltSize;
return GetINTEGERTypeAtOffset(EltTy, IROffset-EltOffset, SourceTy,
SourceOffset);
}
// Okay, we don't have any better idea of what to pass, so we pass this in an
// integer register that isn't too big to fit the rest of the struct.
unsigned TySizeInBytes =
(unsigned)getContext().getTypeSizeInChars(SourceTy).getQuantity();
assert(TySizeInBytes != SourceOffset && "Empty field?");
// It is always safe to classify this as an integer type up to i64 that
// isn't larger than the structure.
return llvm::IntegerType::get(getVMContext(),
std::min(TySizeInBytes-SourceOffset, 8U)*8);
}
/// GetX86_64ByValArgumentPair - Given a high and low type that can ideally
/// be used as elements of a two register pair to pass or return, return a
/// first class aggregate to represent them. For example, if the low part of
/// a by-value argument should be passed as i32* and the high part as float,
/// return {i32*, float}.
static llvm::Type *
GetX86_64ByValArgumentPair(llvm::Type *Lo, llvm::Type *Hi,
const llvm::DataLayout &TD) {
// In order to correctly satisfy the ABI, we need to the high part to start
// at offset 8. If the high and low parts we inferred are both 4-byte types
// (e.g. i32 and i32) then the resultant struct type ({i32,i32}) won't have
// the second element at offset 8. Check for this:
unsigned LoSize = (unsigned)TD.getTypeAllocSize(Lo);
unsigned HiAlign = TD.getABITypeAlignment(Hi);
unsigned HiStart = llvm::RoundUpToAlignment(LoSize, HiAlign);
assert(HiStart != 0 && HiStart <= 8 && "Invalid x86-64 argument pair!");
// To handle this, we have to increase the size of the low part so that the
// second element will start at an 8 byte offset. We can't increase the size
// of the second element because it might make us access off the end of the
// struct.
if (HiStart != 8) {
// There are usually two sorts of types the ABI generation code can produce
// for the low part of a pair that aren't 8 bytes in size: float or
// i8/i16/i32. This can also include pointers when they are 32-bit (X32 and
// NaCl).
// Promote these to a larger type.
if (Lo->isFloatTy())
Lo = llvm::Type::getDoubleTy(Lo->getContext());
else {
assert((Lo->isIntegerTy() || Lo->isPointerTy())
&& "Invalid/unknown lo type");
Lo = llvm::Type::getInt64Ty(Lo->getContext());
}
}
llvm::StructType *Result = llvm::StructType::get(Lo, Hi, nullptr);
// Verify that the second element is at an 8-byte offset.
assert(TD.getStructLayout(Result)->getElementOffset(1) == 8 &&
"Invalid x86-64 argument pair!");
return Result;
}
ABIArgInfo X86_64ABIInfo::
classifyReturnType(QualType RetTy) const {
// AMD64-ABI 3.2.3p4: Rule 1. Classify the return type with the
// classification algorithm.
X86_64ABIInfo::Class Lo, Hi;
classify(RetTy, 0, Lo, Hi, /*isNamedArg*/ true);
// Check some invariants.
assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
llvm::Type *ResType = nullptr;
switch (Lo) {
case NoClass:
if (Hi == NoClass)
return ABIArgInfo::getIgnore();
// If the low part is just padding, it takes no register, leave ResType
// null.
assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
"Unknown missing lo part");
break;
case SSEUp:
case X87Up:
llvm_unreachable("Invalid classification for lo word.");
// AMD64-ABI 3.2.3p4: Rule 2. Types of class memory are returned via
// hidden argument.
case Memory:
return getIndirectReturnResult(RetTy);
// AMD64-ABI 3.2.3p4: Rule 3. If the class is INTEGER, the next
// available register of the sequence %rax, %rdx is used.
case Integer:
ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
// If we have a sign or zero extended integer, make sure to return Extend
// so that the parameter gets the right LLVM IR attributes.
if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
if (RetTy->isIntegralOrEnumerationType() &&
RetTy->isPromotableIntegerType())
return ABIArgInfo::getExtend();
}
break;
// AMD64-ABI 3.2.3p4: Rule 4. If the class is SSE, the next
// available SSE register of the sequence %xmm0, %xmm1 is used.
case SSE:
ResType = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
break;
// AMD64-ABI 3.2.3p4: Rule 6. If the class is X87, the value is
// returned on the X87 stack in %st0 as 80-bit x87 number.
case X87:
ResType = llvm::Type::getX86_FP80Ty(getVMContext());
break;
// AMD64-ABI 3.2.3p4: Rule 8. If the class is COMPLEX_X87, the real
// part of the value is returned in %st0 and the imaginary part in
// %st1.
case ComplexX87:
assert(Hi == ComplexX87 && "Unexpected ComplexX87 classification.");
ResType = llvm::StructType::get(llvm::Type::getX86_FP80Ty(getVMContext()),
llvm::Type::getX86_FP80Ty(getVMContext()),
nullptr);
break;
}
llvm::Type *HighPart = nullptr;
switch (Hi) {
// Memory was handled previously and X87 should
// never occur as a hi class.
case Memory:
case X87:
llvm_unreachable("Invalid classification for hi word.");
case ComplexX87: // Previously handled.
case NoClass:
break;
case Integer:
HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
if (Lo == NoClass) // Return HighPart at offset 8 in memory.
return ABIArgInfo::getDirect(HighPart, 8);
break;
case SSE:
HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
if (Lo == NoClass) // Return HighPart at offset 8 in memory.
return ABIArgInfo::getDirect(HighPart, 8);
break;
// AMD64-ABI 3.2.3p4: Rule 5. If the class is SSEUP, the eightbyte
// is passed in the next available eightbyte chunk if the last used
// vector register.
//
// SSEUP should always be preceded by SSE, just widen.
case SSEUp:
assert(Lo == SSE && "Unexpected SSEUp classification.");
ResType = GetByteVectorType(RetTy);
break;
// AMD64-ABI 3.2.3p4: Rule 7. If the class is X87UP, the value is
// returned together with the previous X87 value in %st0.
case X87Up:
// If X87Up is preceded by X87, we don't need to do
// anything. However, in some cases with unions it may not be
// preceded by X87. In such situations we follow gcc and pass the
// extra bits in an SSE reg.
if (Lo != X87) {
HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
if (Lo == NoClass) // Return HighPart at offset 8 in memory.
return ABIArgInfo::getDirect(HighPart, 8);
}
break;
}
// If a high part was specified, merge it together with the low part. It is
// known to pass in the high eightbyte of the result. We do this by forming a
// first class struct aggregate with the high and low part: {low, high}
if (HighPart)
ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
return ABIArgInfo::getDirect(ResType);
}
ABIArgInfo X86_64ABIInfo::classifyArgumentType(
QualType Ty, unsigned freeIntRegs, unsigned &neededInt, unsigned &neededSSE,
bool isNamedArg)
const
{
Ty = useFirstFieldIfTransparentUnion(Ty);
X86_64ABIInfo::Class Lo, Hi;
classify(Ty, 0, Lo, Hi, isNamedArg);
// Check some invariants.
// FIXME: Enforce these by construction.
assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
neededInt = 0;
neededSSE = 0;
llvm::Type *ResType = nullptr;
switch (Lo) {
case NoClass:
if (Hi == NoClass)
return ABIArgInfo::getIgnore();
// If the low part is just padding, it takes no register, leave ResType
// null.
assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
"Unknown missing lo part");
break;
// AMD64-ABI 3.2.3p3: Rule 1. If the class is MEMORY, pass the argument
// on the stack.
case Memory:
// AMD64-ABI 3.2.3p3: Rule 5. If the class is X87, X87UP or
// COMPLEX_X87, it is passed in memory.
case X87:
case ComplexX87:
if (getRecordArgABI(Ty, getCXXABI()) == CGCXXABI::RAA_Indirect)
++neededInt;
return getIndirectResult(Ty, freeIntRegs);
case SSEUp:
case X87Up:
llvm_unreachable("Invalid classification for lo word.");
// AMD64-ABI 3.2.3p3: Rule 2. If the class is INTEGER, the next
// available register of the sequence %rdi, %rsi, %rdx, %rcx, %r8
// and %r9 is used.
case Integer:
++neededInt;
// Pick an 8-byte type based on the preferred type.
ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 0, Ty, 0);
// If we have a sign or zero extended integer, make sure to return Extend
// so that the parameter gets the right LLVM IR attributes.
if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
if (Ty->isIntegralOrEnumerationType() &&
Ty->isPromotableIntegerType())
return ABIArgInfo::getExtend();
}
break;
// AMD64-ABI 3.2.3p3: Rule 3. If the class is SSE, the next
// available SSE register is used, the registers are taken in the
// order from %xmm0 to %xmm7.
case SSE: {
llvm::Type *IRType = CGT.ConvertType(Ty);
ResType = GetSSETypeAtOffset(IRType, 0, Ty, 0);
++neededSSE;
break;
}
}
llvm::Type *HighPart = nullptr;
switch (Hi) {
// Memory was handled previously, ComplexX87 and X87 should
// never occur as hi classes, and X87Up must be preceded by X87,
// which is passed in memory.
case Memory:
case X87:
case ComplexX87:
llvm_unreachable("Invalid classification for hi word.");
case NoClass: break;
case Integer:
++neededInt;
// Pick an 8-byte type based on the preferred type.
HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
if (Lo == NoClass) // Pass HighPart at offset 8 in memory.
return ABIArgInfo::getDirect(HighPart, 8);
break;
// X87Up generally doesn't occur here (long double is passed in
// memory), except in situations involving unions.
case X87Up:
case SSE:
HighPart = GetSSETypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
if (Lo == NoClass) // Pass HighPart at offset 8 in memory.
return ABIArgInfo::getDirect(HighPart, 8);
++neededSSE;
break;
// AMD64-ABI 3.2.3p3: Rule 4. If the class is SSEUP, the
// eightbyte is passed in the upper half of the last used SSE
// register. This only happens when 128-bit vectors are passed.
case SSEUp:
assert(Lo == SSE && "Unexpected SSEUp classification");
ResType = GetByteVectorType(Ty);
break;
}
// If a high part was specified, merge it together with the low part. It is
// known to pass in the high eightbyte of the result. We do this by forming a
// first class struct aggregate with the high and low part: {low, high}
if (HighPart)
ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
return ABIArgInfo::getDirect(ResType);
}
void X86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
if (!getCXXABI().classifyReturnType(FI))
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
// Keep track of the number of assigned registers.
unsigned freeIntRegs = 6, freeSSERegs = 8;
// If the return value is indirect, then the hidden argument is consuming one
// integer register.
if (FI.getReturnInfo().isIndirect())
--freeIntRegs;
// The chain argument effectively gives us another free register.
if (FI.isChainCall())
++freeIntRegs;
unsigned NumRequiredArgs = FI.getNumRequiredArgs();
// AMD64-ABI 3.2.3p3: Once arguments are classified, the registers
// get assigned (in left-to-right order) for passing as follows...
unsigned ArgNo = 0;
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it, ++ArgNo) {
bool IsNamedArg = ArgNo < NumRequiredArgs;
unsigned neededInt, neededSSE;
it->info = classifyArgumentType(it->type, freeIntRegs, neededInt,
neededSSE, IsNamedArg);
// AMD64-ABI 3.2.3p3: If there are no registers available for any
// eightbyte of an argument, the whole argument is passed on the
// stack. If registers have already been assigned for some
// eightbytes of such an argument, the assignments get reverted.
if (freeIntRegs >= neededInt && freeSSERegs >= neededSSE) {
freeIntRegs -= neededInt;
freeSSERegs -= neededSSE;
} else {
it->info = getIndirectResult(it->type, freeIntRegs);
}
}
}
static Address EmitX86_64VAArgFromMemory(CodeGenFunction &CGF,
Address VAListAddr, QualType Ty) {
Address overflow_arg_area_p = CGF.Builder.CreateStructGEP(
VAListAddr, 2, CharUnits::fromQuantity(8), "overflow_arg_area_p");
llvm::Value *overflow_arg_area =
CGF.Builder.CreateLoad(overflow_arg_area_p, "overflow_arg_area");
// AMD64-ABI 3.5.7p5: Step 7. Align l->overflow_arg_area upwards to a 16
// byte boundary if alignment needed by type exceeds 8 byte boundary.
// It isn't stated explicitly in the standard, but in practice we use
// alignment greater than 16 where necessary.
CharUnits Align = CGF.getContext().getTypeAlignInChars(Ty);
if (Align > CharUnits::fromQuantity(8)) {
overflow_arg_area = emitRoundPointerUpToAlignment(CGF, overflow_arg_area,
Align);
}
// AMD64-ABI 3.5.7p5: Step 8. Fetch type from l->overflow_arg_area.
llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
llvm::Value *Res =
CGF.Builder.CreateBitCast(overflow_arg_area,
llvm::PointerType::getUnqual(LTy));
// AMD64-ABI 3.5.7p5: Step 9. Set l->overflow_arg_area to:
// l->overflow_arg_area + sizeof(type).
// AMD64-ABI 3.5.7p5: Step 10. Align l->overflow_arg_area upwards to
// an 8 byte boundary.
uint64_t SizeInBytes = (CGF.getContext().getTypeSize(Ty) + 7) / 8;
llvm::Value *Offset =
llvm::ConstantInt::get(CGF.Int32Ty, (SizeInBytes + 7) & ~7);
overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset,
"overflow_arg_area.next");
CGF.Builder.CreateStore(overflow_arg_area, overflow_arg_area_p);
// AMD64-ABI 3.5.7p5: Step 11. Return the fetched type.
return Address(Res, Align);
}
Address X86_64ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
// Assume that va_list type is correct; should be pointer to LLVM type:
// struct {
// i32 gp_offset;
// i32 fp_offset;
// i8* overflow_arg_area;
// i8* reg_save_area;
// };
unsigned neededInt, neededSSE;
Ty = getContext().getCanonicalType(Ty);
ABIArgInfo AI = classifyArgumentType(Ty, 0, neededInt, neededSSE,
/*isNamedArg*/false);
// AMD64-ABI 3.5.7p5: Step 1. Determine whether type may be passed
// in the registers. If not go to step 7.
if (!neededInt && !neededSSE)
return EmitX86_64VAArgFromMemory(CGF, VAListAddr, Ty);
// AMD64-ABI 3.5.7p5: Step 2. Compute num_gp to hold the number of
// general purpose registers needed to pass type and num_fp to hold
// the number of floating point registers needed.
// AMD64-ABI 3.5.7p5: Step 3. Verify whether arguments fit into
// registers. In the case: l->gp_offset > 48 - num_gp * 8 or
// l->fp_offset > 304 - num_fp * 16 go to step 7.
//
// NOTE: 304 is a typo, there are (6 * 8 + 8 * 16) = 176 bytes of
// register save space).
llvm::Value *InRegs = nullptr;
Address gp_offset_p = Address::invalid(), fp_offset_p = Address::invalid();
llvm::Value *gp_offset = nullptr, *fp_offset = nullptr;
if (neededInt) {
gp_offset_p =
CGF.Builder.CreateStructGEP(VAListAddr, 0, CharUnits::Zero(),
"gp_offset_p");
gp_offset = CGF.Builder.CreateLoad(gp_offset_p, "gp_offset");
InRegs = llvm::ConstantInt::get(CGF.Int32Ty, 48 - neededInt * 8);
InRegs = CGF.Builder.CreateICmpULE(gp_offset, InRegs, "fits_in_gp");
}
if (neededSSE) {
fp_offset_p =
CGF.Builder.CreateStructGEP(VAListAddr, 1, CharUnits::fromQuantity(4),
"fp_offset_p");
fp_offset = CGF.Builder.CreateLoad(fp_offset_p, "fp_offset");
llvm::Value *FitsInFP =
llvm::ConstantInt::get(CGF.Int32Ty, 176 - neededSSE * 16);
FitsInFP = CGF.Builder.CreateICmpULE(fp_offset, FitsInFP, "fits_in_fp");
InRegs = InRegs ? CGF.Builder.CreateAnd(InRegs, FitsInFP) : FitsInFP;
}
llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
// Emit code to load the value if it was passed in registers.
CGF.EmitBlock(InRegBlock);
// AMD64-ABI 3.5.7p5: Step 4. Fetch type from l->reg_save_area with
// an offset of l->gp_offset and/or l->fp_offset. This may require
// copying to a temporary location in case the parameter is passed
// in different register classes or requires an alignment greater
// than 8 for general purpose registers and 16 for XMM registers.
//
// FIXME: This really results in shameful code when we end up needing to
// collect arguments from different places; often what should result in a
// simple assembling of a structure from scattered addresses has many more
// loads than necessary. Can we clean this up?
llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
llvm::Value *RegSaveArea = CGF.Builder.CreateLoad(
CGF.Builder.CreateStructGEP(VAListAddr, 3, CharUnits::fromQuantity(16)),
"reg_save_area");
Address RegAddr = Address::invalid();
if (neededInt && neededSSE) {
// FIXME: Cleanup.
assert(AI.isDirect() && "Unexpected ABI info for mixed regs");
llvm::StructType *ST = cast<llvm::StructType>(AI.getCoerceToType());
Address Tmp = CGF.CreateMemTemp(Ty);
Tmp = CGF.Builder.CreateElementBitCast(Tmp, ST);
assert(ST->getNumElements() == 2 && "Unexpected ABI info for mixed regs");
llvm::Type *TyLo = ST->getElementType(0);
llvm::Type *TyHi = ST->getElementType(1);
assert((TyLo->isFPOrFPVectorTy() ^ TyHi->isFPOrFPVectorTy()) &&
"Unexpected ABI info for mixed regs");
llvm::Type *PTyLo = llvm::PointerType::getUnqual(TyLo);
llvm::Type *PTyHi = llvm::PointerType::getUnqual(TyHi);
llvm::Value *GPAddr = CGF.Builder.CreateGEP(RegSaveArea, gp_offset);
llvm::Value *FPAddr = CGF.Builder.CreateGEP(RegSaveArea, fp_offset);
llvm::Value *RegLoAddr = TyLo->isFPOrFPVectorTy() ? FPAddr : GPAddr;
llvm::Value *RegHiAddr = TyLo->isFPOrFPVectorTy() ? GPAddr : FPAddr;
// Copy the first element.
llvm::Value *V =
CGF.Builder.CreateDefaultAlignedLoad(
CGF.Builder.CreateBitCast(RegLoAddr, PTyLo));
CGF.Builder.CreateStore(V,
CGF.Builder.CreateStructGEP(Tmp, 0, CharUnits::Zero()));
// Copy the second element.
V = CGF.Builder.CreateDefaultAlignedLoad(
CGF.Builder.CreateBitCast(RegHiAddr, PTyHi));
CharUnits Offset = CharUnits::fromQuantity(
getDataLayout().getStructLayout(ST)->getElementOffset(1));
CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1, Offset));
RegAddr = CGF.Builder.CreateElementBitCast(Tmp, LTy);
} else if (neededInt) {
RegAddr = Address(CGF.Builder.CreateGEP(RegSaveArea, gp_offset),
CharUnits::fromQuantity(8));
RegAddr = CGF.Builder.CreateElementBitCast(RegAddr, LTy);
// Copy to a temporary if necessary to ensure the appropriate alignment.
std::pair<CharUnits, CharUnits> SizeAlign =
getContext().getTypeInfoInChars(Ty);
uint64_t TySize = SizeAlign.first.getQuantity();
CharUnits TyAlign = SizeAlign.second;
// Copy into a temporary if the type is more aligned than the
// register save area.
if (TyAlign.getQuantity() > 8) {
Address Tmp = CGF.CreateMemTemp(Ty);
CGF.Builder.CreateMemCpy(Tmp, RegAddr, TySize, false);
RegAddr = Tmp;
}
} else if (neededSSE == 1) {
RegAddr = Address(CGF.Builder.CreateGEP(RegSaveArea, fp_offset),
CharUnits::fromQuantity(16));
RegAddr = CGF.Builder.CreateElementBitCast(RegAddr, LTy);
} else {
assert(neededSSE == 2 && "Invalid number of needed registers!");
// SSE registers are spaced 16 bytes apart in the register save
// area, we need to collect the two eightbytes together.
// The ABI isn't explicit about this, but it seems reasonable
// to assume that the slots are 16-byte aligned, since the stack is
// naturally 16-byte aligned and the prologue is expected to store
// all the SSE registers to the RSA.
Address RegAddrLo = Address(CGF.Builder.CreateGEP(RegSaveArea, fp_offset),
CharUnits::fromQuantity(16));
Address RegAddrHi =
CGF.Builder.CreateConstInBoundsByteGEP(RegAddrLo,
CharUnits::fromQuantity(16));
llvm::Type *DoubleTy = CGF.DoubleTy;
llvm::StructType *ST = llvm::StructType::get(DoubleTy, DoubleTy, nullptr);
llvm::Value *V;
Address Tmp = CGF.CreateMemTemp(Ty);
Tmp = CGF.Builder.CreateElementBitCast(Tmp, ST);
V = CGF.Builder.CreateLoad(
CGF.Builder.CreateElementBitCast(RegAddrLo, DoubleTy));
CGF.Builder.CreateStore(V,
CGF.Builder.CreateStructGEP(Tmp, 0, CharUnits::Zero()));
V = CGF.Builder.CreateLoad(
CGF.Builder.CreateElementBitCast(RegAddrHi, DoubleTy));
CGF.Builder.CreateStore(V,
CGF.Builder.CreateStructGEP(Tmp, 1, CharUnits::fromQuantity(8)));
RegAddr = CGF.Builder.CreateElementBitCast(Tmp, LTy);
}
// AMD64-ABI 3.5.7p5: Step 5. Set:
// l->gp_offset = l->gp_offset + num_gp * 8
// l->fp_offset = l->fp_offset + num_fp * 16.
if (neededInt) {
llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededInt * 8);
CGF.Builder.CreateStore(CGF.Builder.CreateAdd(gp_offset, Offset),
gp_offset_p);
}
if (neededSSE) {
llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededSSE * 16);
CGF.Builder.CreateStore(CGF.Builder.CreateAdd(fp_offset, Offset),
fp_offset_p);
}
CGF.EmitBranch(ContBlock);
// Emit code to load the value if it was passed in memory.
CGF.EmitBlock(InMemBlock);
Address MemAddr = EmitX86_64VAArgFromMemory(CGF, VAListAddr, Ty);
// Return the appropriate result.
CGF.EmitBlock(ContBlock);
Address ResAddr = emitMergePHI(CGF, RegAddr, InRegBlock, MemAddr, InMemBlock,
"vaarg.addr");
return ResAddr;
}
Address X86_64ABIInfo::EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*indirect*/ false,
CGF.getContext().getTypeInfoInChars(Ty),
CharUnits::fromQuantity(8),
/*allowHigherAlign*/ false);
}
ABIArgInfo WinX86_64ABIInfo::classify(QualType Ty, unsigned &FreeSSERegs,
bool IsReturnType) const {
if (Ty->isVoidType())
return ABIArgInfo::getIgnore();
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
TypeInfo Info = getContext().getTypeInfo(Ty);
uint64_t Width = Info.Width;
CharUnits Align = getContext().toCharUnitsFromBits(Info.Align);
const RecordType *RT = Ty->getAs<RecordType>();
if (RT) {
if (!IsReturnType) {
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, getCXXABI()))
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
}
if (RT->getDecl()->hasFlexibleArrayMember())
return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
}
// vectorcall adds the concept of a homogenous vector aggregate, similar to
// other targets.
const Type *Base = nullptr;
uint64_t NumElts = 0;
if (FreeSSERegs && isHomogeneousAggregate(Ty, Base, NumElts)) {
if (FreeSSERegs >= NumElts) {
FreeSSERegs -= NumElts;
if (IsReturnType || Ty->isBuiltinType() || Ty->isVectorType())
return ABIArgInfo::getDirect();
return ABIArgInfo::getExpand();
}
return ABIArgInfo::getIndirect(Align, /*ByVal=*/false);
}
if (Ty->isMemberPointerType()) {
// If the member pointer is represented by an LLVM int or ptr, pass it
// directly.
llvm::Type *LLTy = CGT.ConvertType(Ty);
if (LLTy->isPointerTy() || LLTy->isIntegerTy())
return ABIArgInfo::getDirect();
}
if (RT || Ty->isAnyComplexType() || Ty->isMemberPointerType()) {
// MS x64 ABI requirement: "Any argument that doesn't fit in 8 bytes, or is
// not 1, 2, 4, or 8 bytes, must be passed by reference."
if (Width > 64 || !llvm::isPowerOf2_64(Width))
return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
// Otherwise, coerce it to a small integer.
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Width));
}
// Bool type is always extended to the ABI, other builtin types are not
// extended.
const BuiltinType *BT = Ty->getAs<BuiltinType>();
if (BT && BT->getKind() == BuiltinType::Bool)
return ABIArgInfo::getExtend();
// Mingw64 GCC uses the old 80 bit extended precision floating point unit. It
// passes them indirectly through memory.
if (IsMingw64 && BT && BT->getKind() == BuiltinType::LongDouble) {
const llvm::fltSemantics *LDF = &getTarget().getLongDoubleFormat();
if (LDF == &llvm::APFloat::x87DoubleExtended)
return ABIArgInfo::getIndirect(Align, /*ByVal=*/false);
}
return ABIArgInfo::getDirect();
}
void WinX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
bool IsVectorCall =
FI.getCallingConvention() == llvm::CallingConv::X86_VectorCall;
// We can use up to 4 SSE return registers with vectorcall.
unsigned FreeSSERegs = IsVectorCall ? 4 : 0;
if (!getCXXABI().classifyReturnType(FI))
FI.getReturnInfo() = classify(FI.getReturnType(), FreeSSERegs, true);
// We can use up to 6 SSE register parameters with vectorcall.
FreeSSERegs = IsVectorCall ? 6 : 0;
for (auto &I : FI.arguments())
I.info = classify(I.type, FreeSSERegs, false);
}
Address WinX86_64ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*indirect*/ false,
CGF.getContext().getTypeInfoInChars(Ty),
CharUnits::fromQuantity(8),
/*allowHigherAlign*/ false);
}
// PowerPC-32
namespace {
/// PPC32_SVR4_ABIInfo - The 32-bit PowerPC ELF (SVR4) ABI information.
class PPC32_SVR4_ABIInfo : public DefaultABIInfo {
bool IsSoftFloatABI;
public:
PPC32_SVR4_ABIInfo(CodeGen::CodeGenTypes &CGT, bool SoftFloatABI)
: DefaultABIInfo(CGT), IsSoftFloatABI(SoftFloatABI) {}
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
};
class PPC32TargetCodeGenInfo : public TargetCodeGenInfo {
public:
PPC32TargetCodeGenInfo(CodeGenTypes &CGT, bool SoftFloatABI)
: TargetCodeGenInfo(new PPC32_SVR4_ABIInfo(CGT, SoftFloatABI)) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
// This is recovered from gcc output.
return 1; // r1 is the dedicated stack pointer
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const override;
};
}
Address PPC32_SVR4_ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAList,
QualType Ty) const {
if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
// TODO: Implement this. For now ignore.
(void)CTy;
return Address::invalid();
}
// struct __va_list_tag {
// unsigned char gpr;
// unsigned char fpr;
// unsigned short reserved;
// void *overflow_arg_area;
// void *reg_save_area;
// };
bool isI64 = Ty->isIntegerType() && getContext().getTypeSize(Ty) == 64;
bool isInt =
Ty->isIntegerType() || Ty->isPointerType() || Ty->isAggregateType();
bool isF64 = Ty->isFloatingType() && getContext().getTypeSize(Ty) == 64;
// All aggregates are passed indirectly? That doesn't seem consistent
// with the argument-lowering code.
bool isIndirect = Ty->isAggregateType();
CGBuilderTy &Builder = CGF.Builder;
// The calling convention either uses 1-2 GPRs or 1 FPR.
Address NumRegsAddr = Address::invalid();
if (isInt || IsSoftFloatABI) {
NumRegsAddr = Builder.CreateStructGEP(VAList, 0, CharUnits::Zero(), "gpr");
} else {
NumRegsAddr = Builder.CreateStructGEP(VAList, 1, CharUnits::One(), "fpr");
}
llvm::Value *NumRegs = Builder.CreateLoad(NumRegsAddr, "numUsedRegs");
// "Align" the register count when TY is i64.
if (isI64 || (isF64 && IsSoftFloatABI)) {
NumRegs = Builder.CreateAdd(NumRegs, Builder.getInt8(1));
NumRegs = Builder.CreateAnd(NumRegs, Builder.getInt8((uint8_t) ~1U));
}
llvm::Value *CC =
Builder.CreateICmpULT(NumRegs, Builder.getInt8(8), "cond");
llvm::BasicBlock *UsingRegs = CGF.createBasicBlock("using_regs");
llvm::BasicBlock *UsingOverflow = CGF.createBasicBlock("using_overflow");
llvm::BasicBlock *Cont = CGF.createBasicBlock("cont");
Builder.CreateCondBr(CC, UsingRegs, UsingOverflow);
llvm::Type *DirectTy = CGF.ConvertType(Ty);
if (isIndirect) DirectTy = DirectTy->getPointerTo(0);
// Case 1: consume registers.
Address RegAddr = Address::invalid();
{
CGF.EmitBlock(UsingRegs);
Address RegSaveAreaPtr =
Builder.CreateStructGEP(VAList, 4, CharUnits::fromQuantity(8));
RegAddr = Address(Builder.CreateLoad(RegSaveAreaPtr),
CharUnits::fromQuantity(8));
assert(RegAddr.getElementType() == CGF.Int8Ty);
// Floating-point registers start after the general-purpose registers.
if (!(isInt || IsSoftFloatABI)) {
RegAddr = Builder.CreateConstInBoundsByteGEP(RegAddr,
CharUnits::fromQuantity(32));
}
// Get the address of the saved value by scaling the number of
// registers we've used by the number of
CharUnits RegSize = CharUnits::fromQuantity((isInt || IsSoftFloatABI) ? 4 : 8);
llvm::Value *RegOffset =
Builder.CreateMul(NumRegs, Builder.getInt8(RegSize.getQuantity()));
RegAddr = Address(Builder.CreateInBoundsGEP(CGF.Int8Ty,
RegAddr.getPointer(), RegOffset),
RegAddr.getAlignment().alignmentOfArrayElement(RegSize));
RegAddr = Builder.CreateElementBitCast(RegAddr, DirectTy);
// Increase the used-register count.
NumRegs =
Builder.CreateAdd(NumRegs,
Builder.getInt8((isI64 || (isF64 && IsSoftFloatABI)) ? 2 : 1));
Builder.CreateStore(NumRegs, NumRegsAddr);
CGF.EmitBranch(Cont);
}
// Case 2: consume space in the overflow area.
Address MemAddr = Address::invalid();
{
CGF.EmitBlock(UsingOverflow);
// Everything in the overflow area is rounded up to a size of at least 4.
CharUnits OverflowAreaAlign = CharUnits::fromQuantity(4);
CharUnits Size;
if (!isIndirect) {
auto TypeInfo = CGF.getContext().getTypeInfoInChars(Ty);
Size = TypeInfo.first.RoundUpToAlignment(OverflowAreaAlign);
} else {
Size = CGF.getPointerSize();
}
Address OverflowAreaAddr =
Builder.CreateStructGEP(VAList, 3, CharUnits::fromQuantity(4));
Address OverflowArea(Builder.CreateLoad(OverflowAreaAddr, "argp.cur"),
OverflowAreaAlign);
// Round up address of argument to alignment
CharUnits Align = CGF.getContext().getTypeAlignInChars(Ty);
if (Align > OverflowAreaAlign) {
llvm::Value *Ptr = OverflowArea.getPointer();
OverflowArea = Address(emitRoundPointerUpToAlignment(CGF, Ptr, Align),
Align);
}
MemAddr = Builder.CreateElementBitCast(OverflowArea, DirectTy);
// Increase the overflow area.
OverflowArea = Builder.CreateConstInBoundsByteGEP(OverflowArea, Size);
Builder.CreateStore(OverflowArea.getPointer(), OverflowAreaAddr);
CGF.EmitBranch(Cont);
}
CGF.EmitBlock(Cont);
// Merge the cases with a phi.
Address Result = emitMergePHI(CGF, RegAddr, UsingRegs, MemAddr, UsingOverflow,
"vaarg.addr");
// Load the pointer if the argument was passed indirectly.
if (isIndirect) {
Result = Address(Builder.CreateLoad(Result, "aggr"),
getContext().getTypeAlignInChars(Ty));
}
return Result;
}
bool
PPC32TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
// This is calculated from the LLVM and GCC tables and verified
// against gcc output. AFAIK all ABIs use the same encoding.
CodeGen::CGBuilderTy &Builder = CGF.Builder;
llvm::IntegerType *i8 = CGF.Int8Ty;
llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
// 0-31: r0-31, the 4-byte general-purpose registers
AssignToArrayRange(Builder, Address, Four8, 0, 31);
// 32-63: fp0-31, the 8-byte floating-point registers
AssignToArrayRange(Builder, Address, Eight8, 32, 63);
// 64-76 are various 4-byte special-purpose registers:
// 64: mq
// 65: lr
// 66: ctr
// 67: ap
// 68-75 cr0-7
// 76: xer
AssignToArrayRange(Builder, Address, Four8, 64, 76);
// 77-108: v0-31, the 16-byte vector registers
AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
// 109: vrsave
// 110: vscr
// 111: spe_acc
// 112: spefscr
// 113: sfp
AssignToArrayRange(Builder, Address, Four8, 109, 113);
return false;
}
// PowerPC-64
namespace {
/// PPC64_SVR4_ABIInfo - The 64-bit PowerPC ELF (SVR4) ABI information.
class PPC64_SVR4_ABIInfo : public DefaultABIInfo {
public:
enum ABIKind {
ELFv1 = 0,
ELFv2
};
private:
static const unsigned GPRBits = 64;
ABIKind Kind;
bool HasQPX;
// A vector of float or double will be promoted to <4 x f32> or <4 x f64> and
// will be passed in a QPX register.
bool IsQPXVectorTy(const Type *Ty) const {
if (!HasQPX)
return false;
if (const VectorType *VT = Ty->getAs<VectorType>()) {
unsigned NumElements = VT->getNumElements();
if (NumElements == 1)
return false;
if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::Double)) {
if (getContext().getTypeSize(Ty) <= 256)
return true;
} else if (VT->getElementType()->
isSpecificBuiltinType(BuiltinType::Float)) {
if (getContext().getTypeSize(Ty) <= 128)
return true;
}
}
return false;
}
bool IsQPXVectorTy(QualType Ty) const {
return IsQPXVectorTy(Ty.getTypePtr());
}
public:
PPC64_SVR4_ABIInfo(CodeGen::CodeGenTypes &CGT, ABIKind Kind, bool HasQPX)
: DefaultABIInfo(CGT), Kind(Kind), HasQPX(HasQPX) {}
bool isPromotableTypeForABI(QualType Ty) const;
CharUnits getParamTypeAlignment(QualType Ty) const;
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType Ty) const;
bool isHomogeneousAggregateBaseType(QualType Ty) const override;
bool isHomogeneousAggregateSmallEnough(const Type *Ty,
uint64_t Members) const override;
// TODO: We can add more logic to computeInfo to improve performance.
// Example: For aggregate arguments that fit in a register, we could
// use getDirectInReg (as is done below for structs containing a single
// floating-point value) to avoid pushing them to memory on function
// entry. This would require changing the logic in PPCISelLowering
// when lowering the parameters in the caller and args in the callee.
void computeInfo(CGFunctionInfo &FI) const override {
if (!getCXXABI().classifyReturnType(FI))
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (auto &I : FI.arguments()) {
// We rely on the default argument classification for the most part.
// One exception: An aggregate containing a single floating-point
// or vector item must be passed in a register if one is available.
const Type *T = isSingleElementStruct(I.type, getContext());
if (T) {
const BuiltinType *BT = T->getAs<BuiltinType>();
if (IsQPXVectorTy(T) ||
(T->isVectorType() && getContext().getTypeSize(T) == 128) ||
(BT && BT->isFloatingPoint())) {
QualType QT(T, 0);
I.info = ABIArgInfo::getDirectInReg(CGT.ConvertType(QT));
continue;
}
}
I.info = classifyArgumentType(I.type);
}
}
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
};
class PPC64_SVR4_TargetCodeGenInfo : public TargetCodeGenInfo {
public:
PPC64_SVR4_TargetCodeGenInfo(CodeGenTypes &CGT,
PPC64_SVR4_ABIInfo::ABIKind Kind, bool HasQPX)
: TargetCodeGenInfo(new PPC64_SVR4_ABIInfo(CGT, Kind, HasQPX)) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
// This is recovered from gcc output.
return 1; // r1 is the dedicated stack pointer
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const override;
};
class PPC64TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
public:
PPC64TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
// This is recovered from gcc output.
return 1; // r1 is the dedicated stack pointer
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const override;
};
}
// Return true if the ABI requires Ty to be passed sign- or zero-
// extended to 64 bits.
bool
PPC64_SVR4_ABIInfo::isPromotableTypeForABI(QualType Ty) const {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
// Promotable integer types are required to be promoted by the ABI.
if (Ty->isPromotableIntegerType())
return true;
// In addition to the usual promotable integer types, we also need to
// extend all 32-bit types, since the ABI requires promotion to 64 bits.
if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
switch (BT->getKind()) {
case BuiltinType::Int:
case BuiltinType::UInt:
return true;
default:
break;
}
return false;
}
/// isAlignedParamType - Determine whether a type requires 16-byte or
/// higher alignment in the parameter area. Always returns at least 8.
CharUnits PPC64_SVR4_ABIInfo::getParamTypeAlignment(QualType Ty) const {
// Complex types are passed just like their elements.
if (const ComplexType *CTy = Ty->getAs<ComplexType>())
Ty = CTy->getElementType();
// Only vector types of size 16 bytes need alignment (larger types are
// passed via reference, smaller types are not aligned).
if (IsQPXVectorTy(Ty)) {
if (getContext().getTypeSize(Ty) > 128)
return CharUnits::fromQuantity(32);
return CharUnits::fromQuantity(16);
} else if (Ty->isVectorType()) {
return CharUnits::fromQuantity(getContext().getTypeSize(Ty) == 128 ? 16 : 8);
}
// For single-element float/vector structs, we consider the whole type
// to have the same alignment requirements as its single element.
const Type *AlignAsType = nullptr;
const Type *EltType = isSingleElementStruct(Ty, getContext());
if (EltType) {
const BuiltinType *BT = EltType->getAs<BuiltinType>();
if (IsQPXVectorTy(EltType) || (EltType->isVectorType() &&
getContext().getTypeSize(EltType) == 128) ||
(BT && BT->isFloatingPoint()))
AlignAsType = EltType;
}
// Likewise for ELFv2 homogeneous aggregates.
const Type *Base = nullptr;
uint64_t Members = 0;
if (!AlignAsType && Kind == ELFv2 &&
isAggregateTypeForABI(Ty) && isHomogeneousAggregate(Ty, Base, Members))
AlignAsType = Base;
// With special case aggregates, only vector base types need alignment.
if (AlignAsType && IsQPXVectorTy(AlignAsType)) {
if (getContext().getTypeSize(AlignAsType) > 128)
return CharUnits::fromQuantity(32);
return CharUnits::fromQuantity(16);
} else if (AlignAsType) {
return CharUnits::fromQuantity(AlignAsType->isVectorType() ? 16 : 8);
}
// Otherwise, we only need alignment for any aggregate type that
// has an alignment requirement of >= 16 bytes.
if (isAggregateTypeForABI(Ty) && getContext().getTypeAlign(Ty) >= 128) {
if (HasQPX && getContext().getTypeAlign(Ty) >= 256)
return CharUnits::fromQuantity(32);
return CharUnits::fromQuantity(16);
}
return CharUnits::fromQuantity(8);
}
/// isHomogeneousAggregate - Return true if a type is an ELFv2 homogeneous
/// aggregate. Base is set to the base element type, and Members is set
/// to the number of base elements.
bool ABIInfo::isHomogeneousAggregate(QualType Ty, const Type *&Base,
uint64_t &Members) const {
if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
uint64_t NElements = AT->getSize().getZExtValue();
if (NElements == 0)
return false;
if (!isHomogeneousAggregate(AT->getElementType(), Base, Members))
return false;
Members *= NElements;
} else if (const RecordType *RT = Ty->getAs<RecordType>()) {
const RecordDecl *RD = RT->getDecl();
if (RD->hasFlexibleArrayMember())
return false;
Members = 0;
// If this is a C++ record, check the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
for (const auto &I : CXXRD->bases()) {
// Ignore empty records.
if (isEmptyRecord(getContext(), I.getType(), true))
continue;
uint64_t FldMembers;
if (!isHomogeneousAggregate(I.getType(), Base, FldMembers))
return false;
Members += FldMembers;
}
}
for (const auto *FD : RD->fields()) {
// Ignore (non-zero arrays of) empty records.
QualType FT = FD->getType();
while (const ConstantArrayType *AT =
getContext().getAsConstantArrayType(FT)) {
if (AT->getSize().getZExtValue() == 0)
return false;
FT = AT->getElementType();
}
if (isEmptyRecord(getContext(), FT, true))
continue;
// For compatibility with GCC, ignore empty bitfields in C++ mode.
if (getContext().getLangOpts().CPlusPlus &&
FD->isBitField() && FD->getBitWidthValue(getContext()) == 0)
continue;
uint64_t FldMembers;
if (!isHomogeneousAggregate(FD->getType(), Base, FldMembers))
return false;
Members = (RD->isUnion() ?
std::max(Members, FldMembers) : Members + FldMembers);
}
if (!Base)
return false;
// Ensure there is no padding.
if (getContext().getTypeSize(Base) * Members !=
getContext().getTypeSize(Ty))
return false;
} else {
Members = 1;
if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
Members = 2;
Ty = CT->getElementType();
}
// Most ABIs only support float, double, and some vector type widths.
if (!isHomogeneousAggregateBaseType(Ty))
return false;
// The base type must be the same for all members. Types that
// agree in both total size and mode (float vs. vector) are
// treated as being equivalent here.
const Type *TyPtr = Ty.getTypePtr();
if (!Base)
Base = TyPtr;
if (Base->isVectorType() != TyPtr->isVectorType() ||
getContext().getTypeSize(Base) != getContext().getTypeSize(TyPtr))
return false;
}
return Members > 0 && isHomogeneousAggregateSmallEnough(Base, Members);
}
bool PPC64_SVR4_ABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
// Homogeneous aggregates for ELFv2 must have base types of float,
// double, long double, or 128-bit vectors.
if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
if (BT->getKind() == BuiltinType::Float ||
BT->getKind() == BuiltinType::Double ||
BT->getKind() == BuiltinType::LongDouble)
return true;
}
if (const VectorType *VT = Ty->getAs<VectorType>()) {
if (getContext().getTypeSize(VT) == 128 || IsQPXVectorTy(Ty))
return true;
}
return false;
}
bool PPC64_SVR4_ABIInfo::isHomogeneousAggregateSmallEnough(
const Type *Base, uint64_t Members) const {
// Vector types require one register, floating point types require one
// or two registers depending on their size.
uint32_t NumRegs =
Base->isVectorType() ? 1 : (getContext().getTypeSize(Base) + 63) / 64;
// Homogeneous Aggregates may occupy at most 8 registers.
return Members * NumRegs <= 8;
}
ABIArgInfo
PPC64_SVR4_ABIInfo::classifyArgumentType(QualType Ty) const {
Ty = useFirstFieldIfTransparentUnion(Ty);
if (Ty->isAnyComplexType())
return ABIArgInfo::getDirect();
// Non-Altivec vector types are passed in GPRs (smaller than 16 bytes)
// or via reference (larger than 16 bytes).
if (Ty->isVectorType() && !IsQPXVectorTy(Ty)) {
uint64_t Size = getContext().getTypeSize(Ty);
if (Size > 128)
return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
else if (Size < 128) {
llvm::Type *CoerceTy = llvm::IntegerType::get(getVMContext(), Size);
return ABIArgInfo::getDirect(CoerceTy);
}
}
if (isAggregateTypeForABI(Ty)) {
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
uint64_t ABIAlign = getParamTypeAlignment(Ty).getQuantity();
uint64_t TyAlign = getContext().getTypeAlignInChars(Ty).getQuantity();
// ELFv2 homogeneous aggregates are passed as array types.
const Type *Base = nullptr;
uint64_t Members = 0;
if (Kind == ELFv2 &&
isHomogeneousAggregate(Ty, Base, Members)) {
llvm::Type *BaseTy = CGT.ConvertType(QualType(Base, 0));
llvm::Type *CoerceTy = llvm::ArrayType::get(BaseTy, Members);
return ABIArgInfo::getDirect(CoerceTy);
}
// If an aggregate may end up fully in registers, we do not
// use the ByVal method, but pass the aggregate as array.
// This is usually beneficial since we avoid forcing the
// back-end to store the argument to memory.
uint64_t Bits = getContext().getTypeSize(Ty);
if (Bits > 0 && Bits <= 8 * GPRBits) {
llvm::Type *CoerceTy;
// Types up to 8 bytes are passed as integer type (which will be
// properly aligned in the argument save area doubleword).
if (Bits <= GPRBits)
CoerceTy = llvm::IntegerType::get(getVMContext(),
llvm::RoundUpToAlignment(Bits, 8));
// Larger types are passed as arrays, with the base type selected
// according to the required alignment in the save area.
else {
uint64_t RegBits = ABIAlign * 8;
uint64_t NumRegs = llvm::RoundUpToAlignment(Bits, RegBits) / RegBits;
llvm::Type *RegTy = llvm::IntegerType::get(getVMContext(), RegBits);
CoerceTy = llvm::ArrayType::get(RegTy, NumRegs);
}
return ABIArgInfo::getDirect(CoerceTy);
}
// All other aggregates are passed ByVal.
return ABIArgInfo::getIndirect(CharUnits::fromQuantity(ABIAlign),
/*ByVal=*/true,
/*Realign=*/TyAlign > ABIAlign);
}
return (isPromotableTypeForABI(Ty) ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
ABIArgInfo
PPC64_SVR4_ABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
if (RetTy->isAnyComplexType())
return ABIArgInfo::getDirect();
// Non-Altivec vector types are returned in GPRs (smaller than 16 bytes)
// or via reference (larger than 16 bytes).
if (RetTy->isVectorType() && !IsQPXVectorTy(RetTy)) {
uint64_t Size = getContext().getTypeSize(RetTy);
if (Size > 128)
return getNaturalAlignIndirect(RetTy);
else if (Size < 128) {
llvm::Type *CoerceTy = llvm::IntegerType::get(getVMContext(), Size);
return ABIArgInfo::getDirect(CoerceTy);
}
}
if (isAggregateTypeForABI(RetTy)) {
// ELFv2 homogeneous aggregates are returned as array types.
const Type *Base = nullptr;
uint64_t Members = 0;
if (Kind == ELFv2 &&
isHomogeneousAggregate(RetTy, Base, Members)) {
llvm::Type *BaseTy = CGT.ConvertType(QualType(Base, 0));
llvm::Type *CoerceTy = llvm::ArrayType::get(BaseTy, Members);
return ABIArgInfo::getDirect(CoerceTy);
}
// ELFv2 small aggregates are returned in up to two registers.
uint64_t Bits = getContext().getTypeSize(RetTy);
if (Kind == ELFv2 && Bits <= 2 * GPRBits) {
if (Bits == 0)
return ABIArgInfo::getIgnore();
llvm::Type *CoerceTy;
if (Bits > GPRBits) {
CoerceTy = llvm::IntegerType::get(getVMContext(), GPRBits);
CoerceTy = llvm::StructType::get(CoerceTy, CoerceTy, nullptr);
} else
CoerceTy = llvm::IntegerType::get(getVMContext(),
llvm::RoundUpToAlignment(Bits, 8));
return ABIArgInfo::getDirect(CoerceTy);
}
// All other aggregates are returned indirectly.
return getNaturalAlignIndirect(RetTy);
}
return (isPromotableTypeForABI(RetTy) ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
// Based on ARMABIInfo::EmitVAArg, adjusted for 64-bit machine.
Address PPC64_SVR4_ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
auto TypeInfo = getContext().getTypeInfoInChars(Ty);
TypeInfo.second = getParamTypeAlignment(Ty);
CharUnits SlotSize = CharUnits::fromQuantity(8);
// If we have a complex type and the base type is smaller than 8 bytes,
// the ABI calls for the real and imaginary parts to be right-adjusted
// in separate doublewords. However, Clang expects us to produce a
// pointer to a structure with the two parts packed tightly. So generate
// loads of the real and imaginary parts relative to the va_list pointer,
// and store them to a temporary structure.
if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
CharUnits EltSize = TypeInfo.first / 2;
if (EltSize < SlotSize) {
Address Addr = emitVoidPtrDirectVAArg(CGF, VAListAddr, CGF.Int8Ty,
SlotSize * 2, SlotSize,
SlotSize, /*AllowHigher*/ true);
Address RealAddr = Addr;
Address ImagAddr = RealAddr;
if (CGF.CGM.getDataLayout().isBigEndian()) {
RealAddr = CGF.Builder.CreateConstInBoundsByteGEP(RealAddr,
SlotSize - EltSize);
ImagAddr = CGF.Builder.CreateConstInBoundsByteGEP(ImagAddr,
2 * SlotSize - EltSize);
} else {
ImagAddr = CGF.Builder.CreateConstInBoundsByteGEP(RealAddr, SlotSize);
}
llvm::Type *EltTy = CGF.ConvertTypeForMem(CTy->getElementType());
RealAddr = CGF.Builder.CreateElementBitCast(RealAddr, EltTy);
ImagAddr = CGF.Builder.CreateElementBitCast(ImagAddr, EltTy);
llvm::Value *Real = CGF.Builder.CreateLoad(RealAddr, ".vareal");
llvm::Value *Imag = CGF.Builder.CreateLoad(ImagAddr, ".vaimag");
Address Temp = CGF.CreateMemTemp(Ty, "vacplx");
CGF.EmitStoreOfComplex({Real, Imag}, CGF.MakeAddrLValue(Temp, Ty),
/*init*/ true);
return Temp;
}
}
// Otherwise, just use the general rule.
return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*Indirect*/ false,
TypeInfo, SlotSize, /*AllowHigher*/ true);
}
static bool
PPC64_initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) {
// This is calculated from the LLVM and GCC tables and verified
// against gcc output. AFAIK all ABIs use the same encoding.
CodeGen::CGBuilderTy &Builder = CGF.Builder;
llvm::IntegerType *i8 = CGF.Int8Ty;
llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
// 0-31: r0-31, the 8-byte general-purpose registers
AssignToArrayRange(Builder, Address, Eight8, 0, 31);
// 32-63: fp0-31, the 8-byte floating-point registers
AssignToArrayRange(Builder, Address, Eight8, 32, 63);
// 64-76 are various 4-byte special-purpose registers:
// 64: mq
// 65: lr
// 66: ctr
// 67: ap
// 68-75 cr0-7
// 76: xer
AssignToArrayRange(Builder, Address, Four8, 64, 76);
// 77-108: v0-31, the 16-byte vector registers
AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
// 109: vrsave
// 110: vscr
// 111: spe_acc
// 112: spefscr
// 113: sfp
AssignToArrayRange(Builder, Address, Four8, 109, 113);
return false;
}
bool
PPC64_SVR4_TargetCodeGenInfo::initDwarfEHRegSizeTable(
CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
return PPC64_initDwarfEHRegSizeTable(CGF, Address);
}
bool
PPC64TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
return PPC64_initDwarfEHRegSizeTable(CGF, Address);
}
//===----------------------------------------------------------------------===//
// AArch64 ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class AArch64ABIInfo : public ABIInfo {
public:
enum ABIKind {
AAPCS = 0,
DarwinPCS
};
private:
ABIKind Kind;
public:
AArch64ABIInfo(CodeGenTypes &CGT, ABIKind Kind) : ABIInfo(CGT), Kind(Kind) {}
private:
ABIKind getABIKind() const { return Kind; }
bool isDarwinPCS() const { return Kind == DarwinPCS; }
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType RetTy) const;
bool isHomogeneousAggregateBaseType(QualType Ty) const override;
bool isHomogeneousAggregateSmallEnough(const Type *Ty,
uint64_t Members) const override;
bool isIllegalVectorType(QualType Ty) const;
void computeInfo(CGFunctionInfo &FI) const override {
if (!getCXXABI().classifyReturnType(FI))
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (auto &it : FI.arguments())
it.info = classifyArgumentType(it.type);
}
Address EmitDarwinVAArg(Address VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
Address EmitAAPCSVAArg(Address VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override {
return isDarwinPCS() ? EmitDarwinVAArg(VAListAddr, Ty, CGF)
: EmitAAPCSVAArg(VAListAddr, Ty, CGF);
}
};
class AArch64TargetCodeGenInfo : public TargetCodeGenInfo {
public:
AArch64TargetCodeGenInfo(CodeGenTypes &CGT, AArch64ABIInfo::ABIKind Kind)
: TargetCodeGenInfo(new AArch64ABIInfo(CGT, Kind)) {}
StringRef getARCRetainAutoreleasedReturnValueMarker() const override {
return "mov\tfp, fp\t\t; marker for objc_retainAutoreleaseReturnValue";
}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
return 31;
}
bool doesReturnSlotInterfereWithArgs() const override { return false; }
};
}
ABIArgInfo AArch64ABIInfo::classifyArgumentType(QualType Ty) const {
Ty = useFirstFieldIfTransparentUnion(Ty);
// Handle illegal vector types here.
if (isIllegalVectorType(Ty)) {
uint64_t Size = getContext().getTypeSize(Ty);
// Android promotes <2 x i8> to i16, not i32
if (Size <= 16) {
llvm::Type *ResType = llvm::Type::getInt16Ty(getVMContext());
return ABIArgInfo::getDirect(ResType);
}
if (Size == 32) {
llvm::Type *ResType = llvm::Type::getInt32Ty(getVMContext());
return ABIArgInfo::getDirect(ResType);
}
if (Size == 64) {
llvm::Type *ResType =
llvm::VectorType::get(llvm::Type::getInt32Ty(getVMContext()), 2);
return ABIArgInfo::getDirect(ResType);
}
if (Size == 128) {
llvm::Type *ResType =
llvm::VectorType::get(llvm::Type::getInt32Ty(getVMContext()), 4);
return ABIArgInfo::getDirect(ResType);
}
return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
}
if (!isAggregateTypeForABI(Ty)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
return (Ty->isPromotableIntegerType() && isDarwinPCS()
? ABIArgInfo::getExtend()
: ABIArgInfo::getDirect());
}
// Structures with either a non-trivial destructor or a non-trivial
// copy constructor are always indirect.
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
return getNaturalAlignIndirect(Ty, /*ByVal=*/RAA ==
CGCXXABI::RAA_DirectInMemory);
}
// Empty records are always ignored on Darwin, but actually passed in C++ mode
// elsewhere for GNU compatibility.
if (isEmptyRecord(getContext(), Ty, true)) {
if (!getContext().getLangOpts().CPlusPlus || isDarwinPCS())
return ABIArgInfo::getIgnore();
return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
}
// Homogeneous Floating-point Aggregates (HFAs) need to be expanded.
const Type *Base = nullptr;
uint64_t Members = 0;
if (isHomogeneousAggregate(Ty, Base, Members)) {
return ABIArgInfo::getDirect(
llvm::ArrayType::get(CGT.ConvertType(QualType(Base, 0)), Members));
}
// Aggregates <= 16 bytes are passed directly in registers or on the stack.
uint64_t Size = getContext().getTypeSize(Ty);
if (Size <= 128) {
if (getContext().getLangOpts().Renderscript) {
return coerceToIntArray(Ty, getContext(), getVMContext());
}
unsigned Alignment = getContext().getTypeAlign(Ty);
Size = 64 * ((Size + 63) / 64); // round up to multiple of 8 bytes
// We use a pair of i64 for 16-byte aggregate with 8-byte alignment.
// For aggregates with 16-byte alignment, we use i128.
if (Alignment < 128 && Size == 128) {
llvm::Type *BaseTy = llvm::Type::getInt64Ty(getVMContext());
return ABIArgInfo::getDirect(llvm::ArrayType::get(BaseTy, Size / 64));
}
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Size));
}
return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
}
ABIArgInfo AArch64ABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
// Large vector types should be returned via memory.
if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 128)
return getNaturalAlignIndirect(RetTy);
if (!isAggregateTypeForABI(RetTy)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() && isDarwinPCS()
? ABIArgInfo::getExtend()
: ABIArgInfo::getDirect());
}
if (isEmptyRecord(getContext(), RetTy, true))
return ABIArgInfo::getIgnore();
const Type *Base = nullptr;
uint64_t Members = 0;
if (isHomogeneousAggregate(RetTy, Base, Members))
// Homogeneous Floating-point Aggregates (HFAs) are returned directly.
return ABIArgInfo::getDirect();
// Aggregates <= 16 bytes are returned directly in registers or on the stack.
uint64_t Size = getContext().getTypeSize(RetTy);
if (Size <= 128) {
if (getContext().getLangOpts().Renderscript) {
return coerceToIntArray(RetTy, getContext(), getVMContext());
}
unsigned Alignment = getContext().getTypeAlign(RetTy);
Size = 64 * ((Size + 63) / 64); // round up to multiple of 8 bytes
// We use a pair of i64 for 16-byte aggregate with 8-byte alignment.
// For aggregates with 16-byte alignment, we use i128.
if (Alignment < 128 && Size == 128) {
llvm::Type *BaseTy = llvm::Type::getInt64Ty(getVMContext());
return ABIArgInfo::getDirect(llvm::ArrayType::get(BaseTy, Size / 64));
}
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), Size));
}
return getNaturalAlignIndirect(RetTy);
}
/// isIllegalVectorType - check whether the vector type is legal for AArch64.
bool AArch64ABIInfo::isIllegalVectorType(QualType Ty) const {
if (const VectorType *VT = Ty->getAs<VectorType>()) {
// Check whether VT is legal.
unsigned NumElements = VT->getNumElements();
uint64_t Size = getContext().getTypeSize(VT);
// NumElements should be power of 2 between 1 and 16.
if ((NumElements & (NumElements - 1)) != 0 || NumElements > 16)
return true;
return Size != 64 && (Size != 128 || NumElements == 1);
}
return false;
}
bool AArch64ABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
// Homogeneous aggregates for AAPCS64 must have base types of a floating
// point type or a short-vector type. This is the same as the 32-bit ABI,
// but with the difference that any floating-point type is allowed,
// including __fp16.
if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
if (BT->isFloatingPoint())
return true;
} else if (const VectorType *VT = Ty->getAs<VectorType>()) {
unsigned VecSize = getContext().getTypeSize(VT);
if (VecSize == 64 || VecSize == 128)
return true;
}
return false;
}
bool AArch64ABIInfo::isHomogeneousAggregateSmallEnough(const Type *Base,
uint64_t Members) const {
return Members <= 4;
}
Address AArch64ABIInfo::EmitAAPCSVAArg(Address VAListAddr,
QualType Ty,
CodeGenFunction &CGF) const {
ABIArgInfo AI = classifyArgumentType(Ty);
bool IsIndirect = AI.isIndirect();
llvm::Type *BaseTy = CGF.ConvertType(Ty);
if (IsIndirect)
BaseTy = llvm::PointerType::getUnqual(BaseTy);
else if (AI.getCoerceToType())
BaseTy = AI.getCoerceToType();
unsigned NumRegs = 1;
if (llvm::ArrayType *ArrTy = dyn_cast<llvm::ArrayType>(BaseTy)) {
BaseTy = ArrTy->getElementType();
NumRegs = ArrTy->getNumElements();
}
bool IsFPR = BaseTy->isFloatingPointTy() || BaseTy->isVectorTy();
// The AArch64 va_list type and handling is specified in the Procedure Call
// Standard, section B.4:
//
// struct {
// void *__stack;
// void *__gr_top;
// void *__vr_top;
// int __gr_offs;
// int __vr_offs;
// };
llvm::BasicBlock *MaybeRegBlock = CGF.createBasicBlock("vaarg.maybe_reg");
llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
llvm::BasicBlock *OnStackBlock = CGF.createBasicBlock("vaarg.on_stack");
llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
auto TyInfo = getContext().getTypeInfoInChars(Ty);
CharUnits TyAlign = TyInfo.second;
Address reg_offs_p = Address::invalid();
llvm::Value *reg_offs = nullptr;
int reg_top_index;
CharUnits reg_top_offset;
int RegSize = IsIndirect ? 8 : TyInfo.first.getQuantity();
if (!IsFPR) {
// 3 is the field number of __gr_offs
reg_offs_p =
CGF.Builder.CreateStructGEP(VAListAddr, 3, CharUnits::fromQuantity(24),
"gr_offs_p");
reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "gr_offs");
reg_top_index = 1; // field number for __gr_top
reg_top_offset = CharUnits::fromQuantity(8);
RegSize = llvm::RoundUpToAlignment(RegSize, 8);
} else {
// 4 is the field number of __vr_offs.
reg_offs_p =
CGF.Builder.CreateStructGEP(VAListAddr, 4, CharUnits::fromQuantity(28),
"vr_offs_p");
reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "vr_offs");
reg_top_index = 2; // field number for __vr_top
reg_top_offset = CharUnits::fromQuantity(16);
RegSize = 16 * NumRegs;
}
//=======================================
// Find out where argument was passed
//=======================================
// If reg_offs >= 0 we're already using the stack for this type of
// argument. We don't want to keep updating reg_offs (in case it overflows,
// though anyone passing 2GB of arguments, each at most 16 bytes, deserves
// whatever they get).
llvm::Value *UsingStack = nullptr;
UsingStack = CGF.Builder.CreateICmpSGE(
reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, 0));
CGF.Builder.CreateCondBr(UsingStack, OnStackBlock, MaybeRegBlock);
// Otherwise, at least some kind of argument could go in these registers, the
// question is whether this particular type is too big.
CGF.EmitBlock(MaybeRegBlock);
// Integer arguments may need to correct register alignment (for example a
// "struct { __int128 a; };" gets passed in x_2N, x_{2N+1}). In this case we
// align __gr_offs to calculate the potential address.
if (!IsFPR && !IsIndirect && TyAlign.getQuantity() > 8) {
int Align = TyAlign.getQuantity();
reg_offs = CGF.Builder.CreateAdd(
reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, Align - 1),
"align_regoffs");
reg_offs = CGF.Builder.CreateAnd(
reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, -Align),
"aligned_regoffs");
}
// Update the gr_offs/vr_offs pointer for next call to va_arg on this va_list.
// The fact that this is done unconditionally reflects the fact that
// allocating an argument to the stack also uses up all the remaining
// registers of the appropriate kind.
llvm::Value *NewOffset = nullptr;
NewOffset = CGF.Builder.CreateAdd(
reg_offs, llvm::ConstantInt::get(CGF.Int32Ty, RegSize), "new_reg_offs");
CGF.Builder.CreateStore(NewOffset, reg_offs_p);
// Now we're in a position to decide whether this argument really was in
// registers or not.
llvm::Value *InRegs = nullptr;
InRegs = CGF.Builder.CreateICmpSLE(
NewOffset, llvm::ConstantInt::get(CGF.Int32Ty, 0), "inreg");
CGF.Builder.CreateCondBr(InRegs, InRegBlock, OnStackBlock);
//=======================================
// Argument was in registers
//=======================================
// Now we emit the code for if the argument was originally passed in
// registers. First start the appropriate block:
CGF.EmitBlock(InRegBlock);
llvm::Value *reg_top = nullptr;
Address reg_top_p = CGF.Builder.CreateStructGEP(VAListAddr, reg_top_index,
reg_top_offset, "reg_top_p");
reg_top = CGF.Builder.CreateLoad(reg_top_p, "reg_top");
Address BaseAddr(CGF.Builder.CreateInBoundsGEP(reg_top, reg_offs),
CharUnits::fromQuantity(IsFPR ? 16 : 8));
Address RegAddr = Address::invalid();
llvm::Type *MemTy = CGF.ConvertTypeForMem(Ty);
if (IsIndirect) {
// If it's been passed indirectly (actually a struct), whatever we find from
// stored registers or on the stack will actually be a struct **.
MemTy = llvm::PointerType::getUnqual(MemTy);
}
const Type *Base = nullptr;
uint64_t NumMembers = 0;
bool IsHFA = isHomogeneousAggregate(Ty, Base, NumMembers);
if (IsHFA && NumMembers > 1) {
// Homogeneous aggregates passed in registers will have their elements split
// and stored 16-bytes apart regardless of size (they're notionally in qN,
// qN+1, ...). We reload and store into a temporary local variable
// contiguously.
assert(!IsIndirect && "Homogeneous aggregates should be passed directly");
auto BaseTyInfo = getContext().getTypeInfoInChars(QualType(Base, 0));
llvm::Type *BaseTy = CGF.ConvertType(QualType(Base, 0));
llvm::Type *HFATy = llvm::ArrayType::get(BaseTy, NumMembers);
Address Tmp = CGF.CreateTempAlloca(HFATy,
std::max(TyAlign, BaseTyInfo.second));
// On big-endian platforms, the value will be right-aligned in its slot.
int Offset = 0;
if (CGF.CGM.getDataLayout().isBigEndian() &&
BaseTyInfo.first.getQuantity() < 16)
Offset = 16 - BaseTyInfo.first.getQuantity();
for (unsigned i = 0; i < NumMembers; ++i) {
CharUnits BaseOffset = CharUnits::fromQuantity(16 * i + Offset);
Address LoadAddr =
CGF.Builder.CreateConstInBoundsByteGEP(BaseAddr, BaseOffset);
LoadAddr = CGF.Builder.CreateElementBitCast(LoadAddr, BaseTy);
Address StoreAddr =
CGF.Builder.CreateConstArrayGEP(Tmp, i, BaseTyInfo.first);
llvm::Value *Elem = CGF.Builder.CreateLoad(LoadAddr);
CGF.Builder.CreateStore(Elem, StoreAddr);
}
RegAddr = CGF.Builder.CreateElementBitCast(Tmp, MemTy);
} else {
// Otherwise the object is contiguous in memory.
// It might be right-aligned in its slot.
CharUnits SlotSize = BaseAddr.getAlignment();
if (CGF.CGM.getDataLayout().isBigEndian() && !IsIndirect &&
(IsHFA || !isAggregateTypeForABI(Ty)) &&
TyInfo.first < SlotSize) {
CharUnits Offset = SlotSize - TyInfo.first;
BaseAddr = CGF.Builder.CreateConstInBoundsByteGEP(BaseAddr, Offset);
}
RegAddr = CGF.Builder.CreateElementBitCast(BaseAddr, MemTy);
}
CGF.EmitBranch(ContBlock);
//=======================================
// Argument was on the stack
//=======================================
CGF.EmitBlock(OnStackBlock);
Address stack_p = CGF.Builder.CreateStructGEP(VAListAddr, 0,
CharUnits::Zero(), "stack_p");
llvm::Value *OnStackPtr = CGF.Builder.CreateLoad(stack_p, "stack");
// Again, stack arguments may need realignment. In this case both integer and
// floating-point ones might be affected.
if (!IsIndirect && TyAlign.getQuantity() > 8) {
int Align = TyAlign.getQuantity();
OnStackPtr = CGF.Builder.CreatePtrToInt(OnStackPtr, CGF.Int64Ty);
OnStackPtr = CGF.Builder.CreateAdd(
OnStackPtr, llvm::ConstantInt::get(CGF.Int64Ty, Align - 1),
"align_stack");
OnStackPtr = CGF.Builder.CreateAnd(
OnStackPtr, llvm::ConstantInt::get(CGF.Int64Ty, -Align),
"align_stack");
OnStackPtr = CGF.Builder.CreateIntToPtr(OnStackPtr, CGF.Int8PtrTy);
}
Address OnStackAddr(OnStackPtr,
std::max(CharUnits::fromQuantity(8), TyAlign));
// All stack slots are multiples of 8 bytes.
CharUnits StackSlotSize = CharUnits::fromQuantity(8);
CharUnits StackSize;
if (IsIndirect)
StackSize = StackSlotSize;
else
StackSize = TyInfo.first.RoundUpToAlignment(StackSlotSize);
llvm::Value *StackSizeC = CGF.Builder.getSize(StackSize);
llvm::Value *NewStack =
CGF.Builder.CreateInBoundsGEP(OnStackPtr, StackSizeC, "new_stack");
// Write the new value of __stack for the next call to va_arg
CGF.Builder.CreateStore(NewStack, stack_p);
if (CGF.CGM.getDataLayout().isBigEndian() && !isAggregateTypeForABI(Ty) &&
TyInfo.first < StackSlotSize) {
CharUnits Offset = StackSlotSize - TyInfo.first;
OnStackAddr = CGF.Builder.CreateConstInBoundsByteGEP(OnStackAddr, Offset);
}
OnStackAddr = CGF.Builder.CreateElementBitCast(OnStackAddr, MemTy);
CGF.EmitBranch(ContBlock);
//=======================================
// Tidy up
//=======================================
CGF.EmitBlock(ContBlock);
Address ResAddr = emitMergePHI(CGF, RegAddr, InRegBlock,
OnStackAddr, OnStackBlock, "vaargs.addr");
if (IsIndirect)
return Address(CGF.Builder.CreateLoad(ResAddr, "vaarg.addr"),
TyInfo.second);
return ResAddr;
}
Address AArch64ABIInfo::EmitDarwinVAArg(Address VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
// The backend's lowering doesn't support va_arg for aggregates or
// illegal vector types. Lower VAArg here for these cases and use
// the LLVM va_arg instruction for everything else.
if (!isAggregateTypeForABI(Ty) && !isIllegalVectorType(Ty))
return Address::invalid();
CharUnits SlotSize = CharUnits::fromQuantity(8);
// Empty records are ignored for parameter passing purposes.
if (isEmptyRecord(getContext(), Ty, true)) {
Address Addr(CGF.Builder.CreateLoad(VAListAddr, "ap.cur"), SlotSize);
Addr = CGF.Builder.CreateElementBitCast(Addr, CGF.ConvertTypeForMem(Ty));
return Addr;
}
// The size of the actual thing passed, which might end up just
// being a pointer for indirect types.
auto TyInfo = getContext().getTypeInfoInChars(Ty);
// Arguments bigger than 16 bytes which aren't homogeneous
// aggregates should be passed indirectly.
bool IsIndirect = false;
if (TyInfo.first.getQuantity() > 16) {
const Type *Base = nullptr;
uint64_t Members = 0;
IsIndirect = !isHomogeneousAggregate(Ty, Base, Members);
}
return emitVoidPtrVAArg(CGF, VAListAddr, Ty, IsIndirect,
TyInfo, SlotSize, /*AllowHigherAlign*/ true);
}
//===----------------------------------------------------------------------===//
// ARM ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class ARMABIInfo : public ABIInfo {
public:
enum ABIKind {
APCS = 0,
AAPCS = 1,
AAPCS_VFP = 2,
AAPCS16_VFP = 3,
};
private:
ABIKind Kind;
public:
ARMABIInfo(CodeGenTypes &CGT, ABIKind _Kind) : ABIInfo(CGT), Kind(_Kind) {
setCCs();
}
bool isEABI() const {
switch (getTarget().getTriple().getEnvironment()) {
case llvm::Triple::Android:
case llvm::Triple::EABI:
case llvm::Triple::EABIHF:
case llvm::Triple::GNUEABI:
case llvm::Triple::GNUEABIHF:
return true;
default:
return false;
}
}
bool isEABIHF() const {
switch (getTarget().getTriple().getEnvironment()) {
case llvm::Triple::EABIHF:
case llvm::Triple::GNUEABIHF:
return true;
default:
return false;
}
}
bool isAndroid() const {
return (getTarget().getTriple().getEnvironment() ==
llvm::Triple::Android || getContext().getLangOpts().Renderscript);
}
ABIKind getABIKind() const { return Kind; }
private:
ABIArgInfo classifyReturnType(QualType RetTy, bool isVariadic) const;
ABIArgInfo classifyArgumentType(QualType RetTy, bool isVariadic) const;
bool isIllegalVectorType(QualType Ty) const;
bool isHomogeneousAggregateBaseType(QualType Ty) const override;
bool isHomogeneousAggregateSmallEnough(const Type *Ty,
uint64_t Members) const override;
void computeInfo(CGFunctionInfo &FI) const override;
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
llvm::CallingConv::ID getLLVMDefaultCC() const;
llvm::CallingConv::ID getABIDefaultCC() const;
void setCCs();
};
class ARMTargetCodeGenInfo : public TargetCodeGenInfo {
public:
ARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K)
:TargetCodeGenInfo(new ARMABIInfo(CGT, K)) {}
const ARMABIInfo &getABIInfo() const {
return static_cast<const ARMABIInfo&>(TargetCodeGenInfo::getABIInfo());
}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
return 13;
}
StringRef getARCRetainAutoreleasedReturnValueMarker() const override {
return "mov\tr7, r7\t\t@ marker for objc_retainAutoreleaseReturnValue";
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const override {
llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
// 0-15 are the 16 integer registers.
AssignToArrayRange(CGF.Builder, Address, Four8, 0, 15);
return false;
}
unsigned getSizeOfUnwindException() const override {
if (getABIInfo().isEABI()) return 88;
return TargetCodeGenInfo::getSizeOfUnwindException();
}
void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const override {
const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
if (!FD)
return;
const ARMInterruptAttr *Attr = FD->getAttr<ARMInterruptAttr>();
if (!Attr)
return;
const char *Kind;
switch (Attr->getInterrupt()) {
case ARMInterruptAttr::Generic: Kind = ""; break;
case ARMInterruptAttr::IRQ: Kind = "IRQ"; break;
case ARMInterruptAttr::FIQ: Kind = "FIQ"; break;
case ARMInterruptAttr::SWI: Kind = "SWI"; break;
case ARMInterruptAttr::ABORT: Kind = "ABORT"; break;
case ARMInterruptAttr::UNDEF: Kind = "UNDEF"; break;
}
llvm::Function *Fn = cast<llvm::Function>(GV);
Fn->addFnAttr("interrupt", Kind);
ARMABIInfo::ABIKind ABI = cast<ARMABIInfo>(getABIInfo()).getABIKind();
if (ABI == ARMABIInfo::APCS)
return;
// AAPCS guarantees that sp will be 8-byte aligned on any public interface,
// however this is not necessarily true on taking any interrupt. Instruct
// the backend to perform a realignment as part of the function prologue.
llvm::AttrBuilder B;
B.addStackAlignmentAttr(8);
Fn->addAttributes(llvm::AttributeSet::FunctionIndex,
llvm::AttributeSet::get(CGM.getLLVMContext(),
llvm::AttributeSet::FunctionIndex,
B));
}
};
class WindowsARMTargetCodeGenInfo : public ARMTargetCodeGenInfo {
void addStackProbeSizeTargetAttribute(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const;
public:
WindowsARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K)
: ARMTargetCodeGenInfo(CGT, K) {}
void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const override;
};
void WindowsARMTargetCodeGenInfo::addStackProbeSizeTargetAttribute(
const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &CGM) const {
if (!isa<FunctionDecl>(D))
return;
if (CGM.getCodeGenOpts().StackProbeSize == 4096)
return;
llvm::Function *F = cast<llvm::Function>(GV);
F->addFnAttr("stack-probe-size",
llvm::utostr(CGM.getCodeGenOpts().StackProbeSize));
}
void WindowsARMTargetCodeGenInfo::setTargetAttributes(
const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &CGM) const {
ARMTargetCodeGenInfo::setTargetAttributes(D, GV, CGM);
addStackProbeSizeTargetAttribute(D, GV, CGM);
}
}
void ARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
if (!getCXXABI().classifyReturnType(FI))
FI.getReturnInfo() =
classifyReturnType(FI.getReturnType(), FI.isVariadic());
for (auto &I : FI.arguments())
I.info = classifyArgumentType(I.type, FI.isVariadic());
// Always honor user-specified calling convention.
if (FI.getCallingConvention() != llvm::CallingConv::C)
return;
llvm::CallingConv::ID cc = getRuntimeCC();
if (cc != llvm::CallingConv::C)
FI.setEffectiveCallingConvention(cc);
}
/// Return the default calling convention that LLVM will use.
llvm::CallingConv::ID ARMABIInfo::getLLVMDefaultCC() const {
// The default calling convention that LLVM will infer.
if (isEABIHF() || getTarget().getTriple().isWatchOS())
return llvm::CallingConv::ARM_AAPCS_VFP;
else if (isEABI())
return llvm::CallingConv::ARM_AAPCS;
else
return llvm::CallingConv::ARM_APCS;
}
/// Return the calling convention that our ABI would like us to use
/// as the C calling convention.
llvm::CallingConv::ID ARMABIInfo::getABIDefaultCC() const {
switch (getABIKind()) {
case APCS: return llvm::CallingConv::ARM_APCS;
case AAPCS: return llvm::CallingConv::ARM_AAPCS;
case AAPCS_VFP: return llvm::CallingConv::ARM_AAPCS_VFP;
case AAPCS16_VFP: return llvm::CallingConv::ARM_AAPCS_VFP;
}
llvm_unreachable("bad ABI kind");
}
void ARMABIInfo::setCCs() {
assert(getRuntimeCC() == llvm::CallingConv::C);
// Don't muddy up the IR with a ton of explicit annotations if
// they'd just match what LLVM will infer from the triple.
llvm::CallingConv::ID abiCC = getABIDefaultCC();
if (abiCC != getLLVMDefaultCC())
RuntimeCC = abiCC;
// AAPCS apparently requires runtime support functions to be soft-float, but
// that's almost certainly for historic reasons (Thumb1 not supporting VFP
// most likely). It's more convenient for AAPCS16_VFP to be hard-float.
switch (getABIKind()) {
case APCS:
case AAPCS16_VFP:
if (abiCC != getLLVMDefaultCC())
BuiltinCC = abiCC;
break;
case AAPCS:
case AAPCS_VFP:
BuiltinCC = llvm::CallingConv::ARM_AAPCS;
break;
}
}
ABIArgInfo ARMABIInfo::classifyArgumentType(QualType Ty,
bool isVariadic) const {
// 6.1.2.1 The following argument types are VFP CPRCs:
// A single-precision floating-point type (including promoted
// half-precision types); A double-precision floating-point type;
// A 64-bit or 128-bit containerized vector type; Homogeneous Aggregate
// with a Base Type of a single- or double-precision floating-point type,
// 64-bit containerized vectors or 128-bit containerized vectors with one
// to four Elements.
bool IsEffectivelyAAPCS_VFP = getABIKind() == AAPCS_VFP && !isVariadic;
Ty = useFirstFieldIfTransparentUnion(Ty);
// Handle illegal vector types here.
if (isIllegalVectorType(Ty)) {
uint64_t Size = getContext().getTypeSize(Ty);
if (Size <= 32) {
llvm::Type *ResType =
llvm::Type::getInt32Ty(getVMContext());
return ABIArgInfo::getDirect(ResType);
}
if (Size == 64) {
llvm::Type *ResType = llvm::VectorType::get(
llvm::Type::getInt32Ty(getVMContext()), 2);
return ABIArgInfo::getDirect(ResType);
}
if (Size == 128) {
llvm::Type *ResType = llvm::VectorType::get(
llvm::Type::getInt32Ty(getVMContext()), 4);
return ABIArgInfo::getDirect(ResType);
}
return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
}
// __fp16 gets passed as if it were an int or float, but with the top 16 bits
// unspecified. This is not done for OpenCL as it handles the half type
// natively, and does not need to interwork with AAPCS code.
if (Ty->isHalfType() && !getContext().getLangOpts().HalfArgsAndReturns) {
llvm::Type *ResType = IsEffectivelyAAPCS_VFP ?
llvm::Type::getFloatTy(getVMContext()) :
llvm::Type::getInt32Ty(getVMContext());
return ABIArgInfo::getDirect(ResType);
}
if (!isAggregateTypeForABI(Ty)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>()) {
Ty = EnumTy->getDecl()->getIntegerType();
}
return (Ty->isPromotableIntegerType() ? ABIArgInfo::getExtend()
: ABIArgInfo::getDirect());
}
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
}
// Ignore empty records.
if (isEmptyRecord(getContext(), Ty, true))
return ABIArgInfo::getIgnore();
if (IsEffectivelyAAPCS_VFP) {
// Homogeneous Aggregates need to be expanded when we can fit the aggregate
// into VFP registers.
const Type *Base = nullptr;
uint64_t Members = 0;
if (isHomogeneousAggregate(Ty, Base, Members)) {
assert(Base && "Base class should be set for homogeneous aggregate");
// Base can be a floating-point or a vector.
return ABIArgInfo::getDirect(nullptr, 0, nullptr, false);
}
} else if (getABIKind() == ARMABIInfo::AAPCS16_VFP) {
// WatchOS does have homogeneous aggregates. Note that we intentionally use
// this convention even for a variadic function: the backend will use GPRs
// if needed.
const Type *Base = nullptr;
uint64_t Members = 0;
if (isHomogeneousAggregate(Ty, Base, Members)) {
assert(Base && Members <= 4 && "unexpected homogeneous aggregate");
llvm::Type *Ty =
llvm::ArrayType::get(CGT.ConvertType(QualType(Base, 0)), Members);
return ABIArgInfo::getDirect(Ty, 0, nullptr, false);
}
}
if (getABIKind() == ARMABIInfo::AAPCS16_VFP &&
getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(16)) {
// WatchOS is adopting the 64-bit AAPCS rule on composite types: if they're
// bigger than 128-bits, they get placed in space allocated by the caller,
// and a pointer is passed.
return ABIArgInfo::getIndirect(
CharUnits::fromQuantity(getContext().getTypeAlign(Ty) / 8), false);
}
// Support byval for ARM.
// The ABI alignment for APCS is 4-byte and for AAPCS at least 4-byte and at
// most 8-byte. We realign the indirect argument if type alignment is bigger
// than ABI alignment.
uint64_t ABIAlign = 4;
uint64_t TyAlign = getContext().getTypeAlign(Ty) / 8;
if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
getABIKind() == ARMABIInfo::AAPCS)
ABIAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
if (getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(64)) {
assert(getABIKind() != ARMABIInfo::AAPCS16_VFP && "unexpected byval");
return ABIArgInfo::getIndirect(CharUnits::fromQuantity(ABIAlign),
/*ByVal=*/true,
/*Realign=*/TyAlign > ABIAlign);
}
if (getContext().getLangOpts().Renderscript) {
return coerceToIntArray(Ty, getContext(), getVMContext());
}
// Otherwise, pass by coercing to a structure of the appropriate size.
llvm::Type* ElemTy;
unsigned SizeRegs;
// FIXME: Try to match the types of the arguments more accurately where
// we can.
if (getContext().getTypeAlign(Ty) <= 32) {
ElemTy = llvm::Type::getInt32Ty(getVMContext());
SizeRegs = (getContext().getTypeSize(Ty) + 31) / 32;
} else {
ElemTy = llvm::Type::getInt64Ty(getVMContext());
SizeRegs = (getContext().getTypeSize(Ty) + 63) / 64;
}
return ABIArgInfo::getDirect(llvm::ArrayType::get(ElemTy, SizeRegs));
}
static bool isIntegerLikeType(QualType Ty, ASTContext &Context,
llvm::LLVMContext &VMContext) {
// APCS, C Language Calling Conventions, Non-Simple Return Values: A structure
// is called integer-like if its size is less than or equal to one word, and
// the offset of each of its addressable sub-fields is zero.
uint64_t Size = Context.getTypeSize(Ty);
// Check that the type fits in a word.
if (Size > 32)
return false;
// FIXME: Handle vector types!
if (Ty->isVectorType())
return false;
// Float types are never treated as "integer like".
if (Ty->isRealFloatingType())
return false;
// If this is a builtin or pointer type then it is ok.
if (Ty->getAs<BuiltinType>() || Ty->isPointerType())
return true;
// Small complex integer types are "integer like".
if (const ComplexType *CT = Ty->getAs<ComplexType>())
return isIntegerLikeType(CT->getElementType(), Context, VMContext);
// Single element and zero sized arrays should be allowed, by the definition
// above, but they are not.
// Otherwise, it must be a record type.
const RecordType *RT = Ty->getAs<RecordType>();
if (!RT) return false;
// Ignore records with flexible arrays.
const RecordDecl *RD = RT->getDecl();
if (RD->hasFlexibleArrayMember())
return false;
// Check that all sub-fields are at offset 0, and are themselves "integer
// like".
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
bool HadField = false;
unsigned idx = 0;
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i, ++idx) {
const FieldDecl *FD = *i;
// Bit-fields are not addressable, we only need to verify they are "integer
// like". We still have to disallow a subsequent non-bitfield, for example:
// struct { int : 0; int x }
// is non-integer like according to gcc.
if (FD->isBitField()) {
if (!RD->isUnion())
HadField = true;
if (!isIntegerLikeType(FD->getType(), Context, VMContext))
return false;
continue;
}
// Check if this field is at offset 0.
if (Layout.getFieldOffset(idx) != 0)
return false;
if (!isIntegerLikeType(FD->getType(), Context, VMContext))
return false;
// Only allow at most one field in a structure. This doesn't match the
// wording above, but follows gcc in situations with a field following an
// empty structure.
if (!RD->isUnion()) {
if (HadField)
return false;
HadField = true;
}
}
return true;
}
ABIArgInfo ARMABIInfo::classifyReturnType(QualType RetTy,
bool isVariadic) const {
bool IsEffectivelyAAPCS_VFP =
(getABIKind() == AAPCS_VFP || getABIKind() == AAPCS16_VFP) && !isVariadic;
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
// Large vector types should be returned via memory.
if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 128) {
return getNaturalAlignIndirect(RetTy);
}
// __fp16 gets returned as if it were an int or float, but with the top 16
// bits unspecified. This is not done for OpenCL as it handles the half type
// natively, and does not need to interwork with AAPCS code.
if (RetTy->isHalfType() && !getContext().getLangOpts().HalfArgsAndReturns) {
llvm::Type *ResType = IsEffectivelyAAPCS_VFP ?
llvm::Type::getFloatTy(getVMContext()) :
llvm::Type::getInt32Ty(getVMContext());
return ABIArgInfo::getDirect(ResType);
}
if (!isAggregateTypeForABI(RetTy)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return RetTy->isPromotableIntegerType() ? ABIArgInfo::getExtend()
: ABIArgInfo::getDirect();
}
// Are we following APCS?
if (getABIKind() == APCS) {
if (isEmptyRecord(getContext(), RetTy, false))
return ABIArgInfo::getIgnore();
// Complex types are all returned as packed integers.
//
// FIXME: Consider using 2 x vector types if the back end handles them
// correctly.
if (RetTy->isAnyComplexType())
return ABIArgInfo::getDirect(llvm::IntegerType::get(
getVMContext(), getContext().getTypeSize(RetTy)));
// Integer like structures are returned in r0.
if (isIntegerLikeType(RetTy, getContext(), getVMContext())) {
// Return in the smallest viable integer type.
uint64_t Size = getContext().getTypeSize(RetTy);
if (Size <= 8)
return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
if (Size <= 16)
return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
}
// Otherwise return in memory.
return getNaturalAlignIndirect(RetTy);
}
// Otherwise this is an AAPCS variant.
if (isEmptyRecord(getContext(), RetTy, true))
return ABIArgInfo::getIgnore();
// Check for homogeneous aggregates with AAPCS-VFP.
if (IsEffectivelyAAPCS_VFP) {
const Type *Base = nullptr;
uint64_t Members = 0;
if (isHomogeneousAggregate(RetTy, Base, Members)) {
assert(Base && "Base class should be set for homogeneous aggregate");
// Homogeneous Aggregates are returned directly.
return ABIArgInfo::getDirect(nullptr, 0, nullptr, false);
}
}
// Aggregates <= 4 bytes are returned in r0; other aggregates
// are returned indirectly.
uint64_t Size = getContext().getTypeSize(RetTy);
if (Size <= 32) {
if (getContext().getLangOpts().Renderscript) {
return coerceToIntArray(RetTy, getContext(), getVMContext());
}
if (getDataLayout().isBigEndian())
// Return in 32 bit integer integer type (as if loaded by LDR, AAPCS 5.4)
return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
// Return in the smallest viable integer type.
if (Size <= 8)
return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
if (Size <= 16)
return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
} else if (Size <= 128 && getABIKind() == AAPCS16_VFP) {
llvm::Type *Int32Ty = llvm::Type::getInt32Ty(getVMContext());
llvm::Type *CoerceTy =
llvm::ArrayType::get(Int32Ty, llvm::RoundUpToAlignment(Size, 32) / 32);
return ABIArgInfo::getDirect(CoerceTy);
}
return getNaturalAlignIndirect(RetTy);
}
/// isIllegalVector - check whether Ty is an illegal vector type.
bool ARMABIInfo::isIllegalVectorType(QualType Ty) const {
if (const VectorType *VT = Ty->getAs<VectorType> ()) {
if (isAndroid()) {
// Android shipped using Clang 3.1, which supported a slightly different
// vector ABI. The primary differences were that 3-element vector types
// were legal, and so were sub 32-bit vectors (i.e. <2 x i8>). This path
// accepts that legacy behavior for Android only.
// Check whether VT is legal.
unsigned NumElements = VT->getNumElements();
// NumElements should be power of 2 or equal to 3.
if (!llvm::isPowerOf2_32(NumElements) && NumElements != 3)
return true;
} else {
// Check whether VT is legal.
unsigned NumElements = VT->getNumElements();
uint64_t Size = getContext().getTypeSize(VT);
// NumElements should be power of 2.
if (!llvm::isPowerOf2_32(NumElements))
return true;
// Size should be greater than 32 bits.
return Size <= 32;
}
}
return false;
}
bool ARMABIInfo::isHomogeneousAggregateBaseType(QualType Ty) const {
// Homogeneous aggregates for AAPCS-VFP must have base types of float,
// double, or 64-bit or 128-bit vectors.
if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
if (BT->getKind() == BuiltinType::Float ||
BT->getKind() == BuiltinType::Double ||
BT->getKind() == BuiltinType::LongDouble)
return true;
} else if (const VectorType *VT = Ty->getAs<VectorType>()) {
unsigned VecSize = getContext().getTypeSize(VT);
if (VecSize == 64 || VecSize == 128)
return true;
}
return false;
}
bool ARMABIInfo::isHomogeneousAggregateSmallEnough(const Type *Base,
uint64_t Members) const {
return Members <= 4;
}
Address ARMABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
CharUnits SlotSize = CharUnits::fromQuantity(4);
// Empty records are ignored for parameter passing purposes.
if (isEmptyRecord(getContext(), Ty, true)) {
Address Addr(CGF.Builder.CreateLoad(VAListAddr), SlotSize);
Addr = CGF.Builder.CreateElementBitCast(Addr, CGF.ConvertTypeForMem(Ty));
return Addr;
}
auto TyInfo = getContext().getTypeInfoInChars(Ty);
CharUnits TyAlignForABI = TyInfo.second;
// Use indirect if size of the illegal vector is bigger than 16 bytes.
bool IsIndirect = false;
const Type *Base = nullptr;
uint64_t Members = 0;
if (TyInfo.first > CharUnits::fromQuantity(16) && isIllegalVectorType(Ty)) {
IsIndirect = true;
// ARMv7k passes structs bigger than 16 bytes indirectly, in space
// allocated by the caller.
} else if (TyInfo.first > CharUnits::fromQuantity(16) &&
getABIKind() == ARMABIInfo::AAPCS16_VFP &&
!isHomogeneousAggregate(Ty, Base, Members)) {
IsIndirect = true;
// Otherwise, bound the type's ABI alignment.
// The ABI alignment for 64-bit or 128-bit vectors is 8 for AAPCS and 4 for
// APCS. For AAPCS, the ABI alignment is at least 4-byte and at most 8-byte.
// Our callers should be prepared to handle an under-aligned address.
} else if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
getABIKind() == ARMABIInfo::AAPCS) {
TyAlignForABI = std::max(TyAlignForABI, CharUnits::fromQuantity(4));
TyAlignForABI = std::min(TyAlignForABI, CharUnits::fromQuantity(8));
} else if (getABIKind() == ARMABIInfo::AAPCS16_VFP) {
// ARMv7k allows type alignment up to 16 bytes.
TyAlignForABI = std::max(TyAlignForABI, CharUnits::fromQuantity(4));
TyAlignForABI = std::min(TyAlignForABI, CharUnits::fromQuantity(16));
} else {
TyAlignForABI = CharUnits::fromQuantity(4);
}
TyInfo.second = TyAlignForABI;
return emitVoidPtrVAArg(CGF, VAListAddr, Ty, IsIndirect, TyInfo,
SlotSize, /*AllowHigherAlign*/ true);
}
//===----------------------------------------------------------------------===//
// NVPTX ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class NVPTXABIInfo : public ABIInfo {
public:
NVPTXABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType Ty) const;
void computeInfo(CGFunctionInfo &FI) const override;
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
};
class NVPTXTargetCodeGenInfo : public TargetCodeGenInfo {
public:
NVPTXTargetCodeGenInfo(CodeGenTypes &CGT)
: TargetCodeGenInfo(new NVPTXABIInfo(CGT)) {}
void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const override;
private:
// Adds a NamedMDNode with F, Name, and Operand as operands, and adds the
// resulting MDNode to the nvvm.annotations MDNode.
static void addNVVMMetadata(llvm::Function *F, StringRef Name, int Operand);
};
ABIArgInfo NVPTXABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
// note: this is different from default ABI
if (!RetTy->isScalarType())
return ABIArgInfo::getDirect();
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
ABIArgInfo NVPTXABIInfo::classifyArgumentType(QualType Ty) const {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
// Return aggregates type as indirect by value
if (isAggregateTypeForABI(Ty))
return getNaturalAlignIndirect(Ty, /* byval */ true);
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
void NVPTXABIInfo::computeInfo(CGFunctionInfo &FI) const {
if (!getCXXABI().classifyReturnType(FI))
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (auto &I : FI.arguments())
I.info = classifyArgumentType(I.type);
// Always honor user-specified calling convention.
if (FI.getCallingConvention() != llvm::CallingConv::C)
return;
FI.setEffectiveCallingConvention(getRuntimeCC());
}
Address NVPTXABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
llvm_unreachable("NVPTX does not support varargs");
}
void NVPTXTargetCodeGenInfo::
setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const{
const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
if (!FD) return;
llvm::Function *F = cast<llvm::Function>(GV);
// Perform special handling in OpenCL mode
if (M.getLangOpts().OpenCL) {
// Use OpenCL function attributes to check for kernel functions
// By default, all functions are device functions
if (FD->hasAttr<OpenCLKernelAttr>()) {
// OpenCL __kernel functions get kernel metadata
// Create !{<func-ref>, metadata !"kernel", i32 1} node
addNVVMMetadata(F, "kernel", 1);
// And kernel functions are not subject to inlining
F->addFnAttr(llvm::Attribute::NoInline);
}
}
// Perform special handling in CUDA mode.
if (M.getLangOpts().CUDA) {
// CUDA __global__ functions get a kernel metadata entry. Since
// __global__ functions cannot be called from the device, we do not
// need to set the noinline attribute.
if (FD->hasAttr<CUDAGlobalAttr>()) {
// Create !{<func-ref>, metadata !"kernel", i32 1} node
addNVVMMetadata(F, "kernel", 1);
}
if (CUDALaunchBoundsAttr *Attr = FD->getAttr<CUDALaunchBoundsAttr>()) {
// Create !{<func-ref>, metadata !"maxntidx", i32 <val>} node
llvm::APSInt MaxThreads(32);
MaxThreads = Attr->getMaxThreads()->EvaluateKnownConstInt(M.getContext());
if (MaxThreads > 0)
addNVVMMetadata(F, "maxntidx", MaxThreads.getExtValue());
// min blocks is an optional argument for CUDALaunchBoundsAttr. If it was
// not specified in __launch_bounds__ or if the user specified a 0 value,
// we don't have to add a PTX directive.
if (Attr->getMinBlocks()) {
llvm::APSInt MinBlocks(32);
MinBlocks = Attr->getMinBlocks()->EvaluateKnownConstInt(M.getContext());
if (MinBlocks > 0)
// Create !{<func-ref>, metadata !"minctasm", i32 <val>} node
addNVVMMetadata(F, "minctasm", MinBlocks.getExtValue());
}
}
}
}
void NVPTXTargetCodeGenInfo::addNVVMMetadata(llvm::Function *F, StringRef Name,
int Operand) {
llvm::Module *M = F->getParent();
llvm::LLVMContext &Ctx = M->getContext();
// Get "nvvm.annotations" metadata node
llvm::NamedMDNode *MD = M->getOrInsertNamedMetadata("nvvm.annotations");
llvm::Metadata *MDVals[] = {
llvm::ConstantAsMetadata::get(F), llvm::MDString::get(Ctx, Name),
llvm::ConstantAsMetadata::get(
llvm::ConstantInt::get(llvm::Type::getInt32Ty(Ctx), Operand))};
// Append metadata to nvvm.annotations
MD->addOperand(llvm::MDNode::get(Ctx, MDVals));
}
}
//===----------------------------------------------------------------------===//
// SystemZ ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class SystemZABIInfo : public ABIInfo {
bool HasVector;
public:
SystemZABIInfo(CodeGenTypes &CGT, bool HV)
: ABIInfo(CGT), HasVector(HV) {}
bool isPromotableIntegerType(QualType Ty) const;
bool isCompoundType(QualType Ty) const;
bool isVectorArgumentType(QualType Ty) const;
bool isFPArgumentType(QualType Ty) const;
QualType GetSingleElementType(QualType Ty) const;
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType ArgTy) const;
void computeInfo(CGFunctionInfo &FI) const override {
if (!getCXXABI().classifyReturnType(FI))
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (auto &I : FI.arguments())
I.info = classifyArgumentType(I.type);
}
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
};
class SystemZTargetCodeGenInfo : public TargetCodeGenInfo {
public:
SystemZTargetCodeGenInfo(CodeGenTypes &CGT, bool HasVector)
: TargetCodeGenInfo(new SystemZABIInfo(CGT, HasVector)) {}
};
}
bool SystemZABIInfo::isPromotableIntegerType(QualType Ty) const {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
// Promotable integer types are required to be promoted by the ABI.
if (Ty->isPromotableIntegerType())
return true;
// 32-bit values must also be promoted.
if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
switch (BT->getKind()) {
case BuiltinType::Int:
case BuiltinType::UInt:
return true;
default:
return false;
}
return false;
}
bool SystemZABIInfo::isCompoundType(QualType Ty) const {
return (Ty->isAnyComplexType() ||
Ty->isVectorType() ||
isAggregateTypeForABI(Ty));
}
bool SystemZABIInfo::isVectorArgumentType(QualType Ty) const {
return (HasVector &&
Ty->isVectorType() &&
getContext().getTypeSize(Ty) <= 128);
}
bool SystemZABIInfo::isFPArgumentType(QualType Ty) const {
if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
switch (BT->getKind()) {
case BuiltinType::Float:
case BuiltinType::Double:
return true;
default:
return false;
}
return false;
}
QualType SystemZABIInfo::GetSingleElementType(QualType Ty) const {
if (const RecordType *RT = Ty->getAsStructureType()) {
const RecordDecl *RD = RT->getDecl();
QualType Found;
// If this is a C++ record, check the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
for (const auto &I : CXXRD->bases()) {
QualType Base = I.getType();
// Empty bases don't affect things either way.
if (isEmptyRecord(getContext(), Base, true))
continue;
if (!Found.isNull())
return Ty;
Found = GetSingleElementType(Base);
}
// Check the fields.
for (const auto *FD : RD->fields()) {
// For compatibility with GCC, ignore empty bitfields in C++ mode.
// Unlike isSingleElementStruct(), empty structure and array fields
// do count. So do anonymous bitfields that aren't zero-sized.
if (getContext().getLangOpts().CPlusPlus &&
FD->isBitField() && FD->getBitWidthValue(getContext()) == 0)
continue;
// Unlike isSingleElementStruct(), arrays do not count.
// Nested structures still do though.
if (!Found.isNull())
return Ty;
Found = GetSingleElementType(FD->getType());
}
// Unlike isSingleElementStruct(), trailing padding is allowed.
// An 8-byte aligned struct s { float f; } is passed as a double.
if (!Found.isNull())
return Found;
}
return Ty;
}
Address SystemZABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
// Assume that va_list type is correct; should be pointer to LLVM type:
// struct {
// i64 __gpr;
// i64 __fpr;
// i8 *__overflow_arg_area;
// i8 *__reg_save_area;
// };
// Every non-vector argument occupies 8 bytes and is passed by preference
// in either GPRs or FPRs. Vector arguments occupy 8 or 16 bytes and are
// always passed on the stack.
Ty = getContext().getCanonicalType(Ty);
auto TyInfo = getContext().getTypeInfoInChars(Ty);
llvm::Type *ArgTy = CGF.ConvertTypeForMem(Ty);
llvm::Type *DirectTy = ArgTy;
ABIArgInfo AI = classifyArgumentType(Ty);
bool IsIndirect = AI.isIndirect();
bool InFPRs = false;
bool IsVector = false;
CharUnits UnpaddedSize;
CharUnits DirectAlign;
if (IsIndirect) {
DirectTy = llvm::PointerType::getUnqual(DirectTy);
UnpaddedSize = DirectAlign = CharUnits::fromQuantity(8);
} else {
if (AI.getCoerceToType())
ArgTy = AI.getCoerceToType();
InFPRs = ArgTy->isFloatTy() || ArgTy->isDoubleTy();
IsVector = ArgTy->isVectorTy();
UnpaddedSize = TyInfo.first;
DirectAlign = TyInfo.second;
}
CharUnits PaddedSize = CharUnits::fromQuantity(8);
if (IsVector && UnpaddedSize > PaddedSize)
PaddedSize = CharUnits::fromQuantity(16);
assert((UnpaddedSize <= PaddedSize) && "Invalid argument size.");
CharUnits Padding = (PaddedSize - UnpaddedSize);
llvm::Type *IndexTy = CGF.Int64Ty;
llvm::Value *PaddedSizeV =
llvm::ConstantInt::get(IndexTy, PaddedSize.getQuantity());
if (IsVector) {
// Work out the address of a vector argument on the stack.
// Vector arguments are always passed in the high bits of a
// single (8 byte) or double (16 byte) stack slot.
Address OverflowArgAreaPtr =
CGF.Builder.CreateStructGEP(VAListAddr, 2, CharUnits::fromQuantity(16),
"overflow_arg_area_ptr");
Address OverflowArgArea =
Address(CGF.Builder.CreateLoad(OverflowArgAreaPtr, "overflow_arg_area"),
TyInfo.second);
Address MemAddr =
CGF.Builder.CreateElementBitCast(OverflowArgArea, DirectTy, "mem_addr");
// Update overflow_arg_area_ptr pointer
llvm::Value *NewOverflowArgArea =
CGF.Builder.CreateGEP(OverflowArgArea.getPointer(), PaddedSizeV,
"overflow_arg_area");
CGF.Builder.CreateStore(NewOverflowArgArea, OverflowArgAreaPtr);
return MemAddr;
}
assert(PaddedSize.getQuantity() == 8);
unsigned MaxRegs, RegCountField, RegSaveIndex;
CharUnits RegPadding;
if (InFPRs) {
MaxRegs = 4; // Maximum of 4 FPR arguments
RegCountField = 1; // __fpr
RegSaveIndex = 16; // save offset for f0
RegPadding = CharUnits(); // floats are passed in the high bits of an FPR
} else {
MaxRegs = 5; // Maximum of 5 GPR arguments
RegCountField = 0; // __gpr
RegSaveIndex = 2; // save offset for r2
RegPadding = Padding; // values are passed in the low bits of a GPR
}
Address RegCountPtr = CGF.Builder.CreateStructGEP(
VAListAddr, RegCountField, RegCountField * CharUnits::fromQuantity(8),
"reg_count_ptr");
llvm::Value *RegCount = CGF.Builder.CreateLoad(RegCountPtr, "reg_count");
llvm::Value *MaxRegsV = llvm::ConstantInt::get(IndexTy, MaxRegs);
llvm::Value *InRegs = CGF.Builder.CreateICmpULT(RegCount, MaxRegsV,
"fits_in_regs");
llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
// Emit code to load the value if it was passed in registers.
CGF.EmitBlock(InRegBlock);
// Work out the address of an argument register.
llvm::Value *ScaledRegCount =
CGF.Builder.CreateMul(RegCount, PaddedSizeV, "scaled_reg_count");
llvm::Value *RegBase =
llvm::ConstantInt::get(IndexTy, RegSaveIndex * PaddedSize.getQuantity()
+ RegPadding.getQuantity());
llvm::Value *RegOffset =
CGF.Builder.CreateAdd(ScaledRegCount, RegBase, "reg_offset");
Address RegSaveAreaPtr =
CGF.Builder.CreateStructGEP(VAListAddr, 3, CharUnits::fromQuantity(24),
"reg_save_area_ptr");
llvm::Value *RegSaveArea =
CGF.Builder.CreateLoad(RegSaveAreaPtr, "reg_save_area");
Address RawRegAddr(CGF.Builder.CreateGEP(RegSaveArea, RegOffset,
"raw_reg_addr"),
PaddedSize);
Address RegAddr =
CGF.Builder.CreateElementBitCast(RawRegAddr, DirectTy, "reg_addr");
// Update the register count
llvm::Value *One = llvm::ConstantInt::get(IndexTy, 1);
llvm::Value *NewRegCount =
CGF.Builder.CreateAdd(RegCount, One, "reg_count");
CGF.Builder.CreateStore(NewRegCount, RegCountPtr);
CGF.EmitBranch(ContBlock);
// Emit code to load the value if it was passed in memory.
CGF.EmitBlock(InMemBlock);
// Work out the address of a stack argument.
Address OverflowArgAreaPtr = CGF.Builder.CreateStructGEP(
VAListAddr, 2, CharUnits::fromQuantity(16), "overflow_arg_area_ptr");
Address OverflowArgArea =
Address(CGF.Builder.CreateLoad(OverflowArgAreaPtr, "overflow_arg_area"),
PaddedSize);
Address RawMemAddr =
CGF.Builder.CreateConstByteGEP(OverflowArgArea, Padding, "raw_mem_addr");
Address MemAddr =
CGF.Builder.CreateElementBitCast(RawMemAddr, DirectTy, "mem_addr");
// Update overflow_arg_area_ptr pointer
llvm::Value *NewOverflowArgArea =
CGF.Builder.CreateGEP(OverflowArgArea.getPointer(), PaddedSizeV,
"overflow_arg_area");
CGF.Builder.CreateStore(NewOverflowArgArea, OverflowArgAreaPtr);
CGF.EmitBranch(ContBlock);
// Return the appropriate result.
CGF.EmitBlock(ContBlock);
Address ResAddr = emitMergePHI(CGF, RegAddr, InRegBlock,
MemAddr, InMemBlock, "va_arg.addr");
if (IsIndirect)
ResAddr = Address(CGF.Builder.CreateLoad(ResAddr, "indirect_arg"),
TyInfo.second);
return ResAddr;
}
ABIArgInfo SystemZABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
if (isVectorArgumentType(RetTy))
return ABIArgInfo::getDirect();
if (isCompoundType(RetTy) || getContext().getTypeSize(RetTy) > 64)
return getNaturalAlignIndirect(RetTy);
return (isPromotableIntegerType(RetTy) ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
ABIArgInfo SystemZABIInfo::classifyArgumentType(QualType Ty) const {
// Handle the generic C++ ABI.
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
// Integers and enums are extended to full register width.
if (isPromotableIntegerType(Ty))
return ABIArgInfo::getExtend();
// Handle vector types and vector-like structure types. Note that
// as opposed to float-like structure types, we do not allow any
// padding for vector-like structures, so verify the sizes match.
uint64_t Size = getContext().getTypeSize(Ty);
QualType SingleElementTy = GetSingleElementType(Ty);
if (isVectorArgumentType(SingleElementTy) &&
getContext().getTypeSize(SingleElementTy) == Size)
return ABIArgInfo::getDirect(CGT.ConvertType(SingleElementTy));
// Values that are not 1, 2, 4 or 8 bytes in size are passed indirectly.
if (Size != 8 && Size != 16 && Size != 32 && Size != 64)
return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
// Handle small structures.
if (const RecordType *RT = Ty->getAs<RecordType>()) {
// Structures with flexible arrays have variable length, so really
// fail the size test above.
const RecordDecl *RD = RT->getDecl();
if (RD->hasFlexibleArrayMember())
return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
// The structure is passed as an unextended integer, a float, or a double.
llvm::Type *PassTy;
if (isFPArgumentType(SingleElementTy)) {
assert(Size == 32 || Size == 64);
if (Size == 32)
PassTy = llvm::Type::getFloatTy(getVMContext());
else
PassTy = llvm::Type::getDoubleTy(getVMContext());
} else
PassTy = llvm::IntegerType::get(getVMContext(), Size);
return ABIArgInfo::getDirect(PassTy);
}
// Non-structure compounds are passed indirectly.
if (isCompoundType(Ty))
return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
return ABIArgInfo::getDirect(nullptr);
}
//===----------------------------------------------------------------------===//
// MSP430 ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class MSP430TargetCodeGenInfo : public TargetCodeGenInfo {
public:
MSP430TargetCodeGenInfo(CodeGenTypes &CGT)
: TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const override;
};
}
void MSP430TargetCodeGenInfo::setTargetAttributes(const Decl *D,
llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const {
if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
if (const MSP430InterruptAttr *attr = FD->getAttr<MSP430InterruptAttr>()) {
// Handle 'interrupt' attribute:
llvm::Function *F = cast<llvm::Function>(GV);
// Step 1: Set ISR calling convention.
F->setCallingConv(llvm::CallingConv::MSP430_INTR);
// Step 2: Add attributes goodness.
F->addFnAttr(llvm::Attribute::NoInline);
// Step 3: Emit ISR vector alias.
unsigned Num = attr->getNumber() / 2;
llvm::GlobalAlias::create(llvm::Function::ExternalLinkage,
"__isr_" + Twine(Num), F);
}
}
}
//===----------------------------------------------------------------------===//
// MIPS ABI Implementation. This works for both little-endian and
// big-endian variants.
//===----------------------------------------------------------------------===//
namespace {
class MipsABIInfo : public ABIInfo {
bool IsO32;
unsigned MinABIStackAlignInBytes, StackAlignInBytes;
void CoerceToIntArgs(uint64_t TySize,
SmallVectorImpl<llvm::Type *> &ArgList) const;
llvm::Type* HandleAggregates(QualType Ty, uint64_t TySize) const;
llvm::Type* returnAggregateInRegs(QualType RetTy, uint64_t Size) const;
llvm::Type* getPaddingType(uint64_t Align, uint64_t Offset) const;
public:
MipsABIInfo(CodeGenTypes &CGT, bool _IsO32) :
ABIInfo(CGT), IsO32(_IsO32), MinABIStackAlignInBytes(IsO32 ? 4 : 8),
StackAlignInBytes(IsO32 ? 8 : 16) {}
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType RetTy, uint64_t &Offset) const;
void computeInfo(CGFunctionInfo &FI) const override;
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
bool shouldSignExtUnsignedType(QualType Ty) const override;
};
class MIPSTargetCodeGenInfo : public TargetCodeGenInfo {
unsigned SizeOfUnwindException;
public:
MIPSTargetCodeGenInfo(CodeGenTypes &CGT, bool IsO32)
: TargetCodeGenInfo(new MipsABIInfo(CGT, IsO32)),
SizeOfUnwindException(IsO32 ? 24 : 32) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const override {
return 29;
}
void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const override {
const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
if (!FD) return;
llvm::Function *Fn = cast<llvm::Function>(GV);
if (FD->hasAttr<Mips16Attr>()) {
Fn->addFnAttr("mips16");
}
else if (FD->hasAttr<NoMips16Attr>()) {
Fn->addFnAttr("nomips16");
}
const MipsInterruptAttr *Attr = FD->getAttr<MipsInterruptAttr>();
if (!Attr)
return;
const char *Kind;
switch (Attr->getInterrupt()) {
case MipsInterruptAttr::eic: Kind = "eic"; break;
case MipsInterruptAttr::sw0: Kind = "sw0"; break;
case MipsInterruptAttr::sw1: Kind = "sw1"; break;
case MipsInterruptAttr::hw0: Kind = "hw0"; break;
case MipsInterruptAttr::hw1: Kind = "hw1"; break;
case MipsInterruptAttr::hw2: Kind = "hw2"; break;
case MipsInterruptAttr::hw3: Kind = "hw3"; break;
case MipsInterruptAttr::hw4: Kind = "hw4"; break;
case MipsInterruptAttr::hw5: Kind = "hw5"; break;
}
Fn->addFnAttr("interrupt", Kind);
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const override;
unsigned getSizeOfUnwindException() const override {
return SizeOfUnwindException;
}
};
}
void MipsABIInfo::CoerceToIntArgs(
uint64_t TySize, SmallVectorImpl<llvm::Type *> &ArgList) const {
llvm::IntegerType *IntTy =
llvm::IntegerType::get(getVMContext(), MinABIStackAlignInBytes * 8);
// Add (TySize / MinABIStackAlignInBytes) args of IntTy.
for (unsigned N = TySize / (MinABIStackAlignInBytes * 8); N; --N)
ArgList.push_back(IntTy);
// If necessary, add one more integer type to ArgList.
unsigned R = TySize % (MinABIStackAlignInBytes * 8);
if (R)
ArgList.push_back(llvm::IntegerType::get(getVMContext(), R));
}
// In N32/64, an aligned double precision floating point field is passed in
// a register.
llvm::Type* MipsABIInfo::HandleAggregates(QualType Ty, uint64_t TySize) const {
SmallVector<llvm::Type*, 8> ArgList, IntArgList;
if (IsO32) {
CoerceToIntArgs(TySize, ArgList);
return llvm::StructType::get(getVMContext(), ArgList);
}
if (Ty->isComplexType())
return CGT.ConvertType(Ty);
const RecordType *RT = Ty->getAs<RecordType>();
// Unions/vectors are passed in integer registers.
if (!RT || !RT->isStructureOrClassType()) {
CoerceToIntArgs(TySize, ArgList);
return llvm::StructType::get(getVMContext(), ArgList);
}
const RecordDecl *RD = RT->getDecl();
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
assert(!(TySize % 8) && "Size of structure must be multiple of 8.");
uint64_t LastOffset = 0;
unsigned idx = 0;
llvm::IntegerType *I64 = llvm::IntegerType::get(getVMContext(), 64);
// Iterate over fields in the struct/class and check if there are any aligned
// double fields.
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i, ++idx) {
const QualType Ty = i->getType();
const BuiltinType *BT = Ty->getAs<BuiltinType>();
if (!BT || BT->getKind() != BuiltinType::Double)
continue;
uint64_t Offset = Layout.getFieldOffset(idx);
if (Offset % 64) // Ignore doubles that are not aligned.
continue;
// Add ((Offset - LastOffset) / 64) args of type i64.
for (unsigned j = (Offset - LastOffset) / 64; j > 0; --j)
ArgList.push_back(I64);
// Add double type.
ArgList.push_back(llvm::Type::getDoubleTy(getVMContext()));
LastOffset = Offset + 64;
}
CoerceToIntArgs(TySize - LastOffset, IntArgList);
ArgList.append(IntArgList.begin(), IntArgList.end());
return llvm::StructType::get(getVMContext(), ArgList);
}
llvm::Type *MipsABIInfo::getPaddingType(uint64_t OrigOffset,
uint64_t Offset) const {
if (OrigOffset + MinABIStackAlignInBytes > Offset)
return nullptr;
return llvm::IntegerType::get(getVMContext(), (Offset - OrigOffset) * 8);
}
ABIArgInfo
MipsABIInfo::classifyArgumentType(QualType Ty, uint64_t &Offset) const {
Ty = useFirstFieldIfTransparentUnion(Ty);
uint64_t OrigOffset = Offset;
uint64_t TySize = getContext().getTypeSize(Ty);
uint64_t Align = getContext().getTypeAlign(Ty) / 8;
Align = std::min(std::max(Align, (uint64_t)MinABIStackAlignInBytes),
(uint64_t)StackAlignInBytes);
unsigned CurrOffset = llvm::RoundUpToAlignment(Offset, Align);
Offset = CurrOffset + llvm::RoundUpToAlignment(TySize, Align * 8) / 8;
if (isAggregateTypeForABI(Ty) || Ty->isVectorType()) {
// Ignore empty aggregates.
if (TySize == 0)
return ABIArgInfo::getIgnore();
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI())) {
Offset = OrigOffset + MinABIStackAlignInBytes;
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
}
// If we have reached here, aggregates are passed directly by coercing to
// another structure type. Padding is inserted if the offset of the
// aggregate is unaligned.
ABIArgInfo ArgInfo =
ABIArgInfo::getDirect(HandleAggregates(Ty, TySize), 0,
getPaddingType(OrigOffset, CurrOffset));
ArgInfo.setInReg(true);
return ArgInfo;
}
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
// All integral types are promoted to the GPR width.
if (Ty->isIntegralOrEnumerationType())
return ABIArgInfo::getExtend();
return ABIArgInfo::getDirect(
nullptr, 0, IsO32 ? nullptr : getPaddingType(OrigOffset, CurrOffset));
}
llvm::Type*
MipsABIInfo::returnAggregateInRegs(QualType RetTy, uint64_t Size) const {
const RecordType *RT = RetTy->getAs<RecordType>();
SmallVector<llvm::Type*, 8> RTList;
if (RT && RT->isStructureOrClassType()) {
const RecordDecl *RD = RT->getDecl();
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
unsigned FieldCnt = Layout.getFieldCount();
// N32/64 returns struct/classes in floating point registers if the
// following conditions are met:
// 1. The size of the struct/class is no larger than 128-bit.
// 2. The struct/class has one or two fields all of which are floating
// point types.
// 3. The offset of the first field is zero (this follows what gcc does).
//
// Any other composite results are returned in integer registers.
//
if (FieldCnt && (FieldCnt <= 2) && !Layout.getFieldOffset(0)) {
RecordDecl::field_iterator b = RD->field_begin(), e = RD->field_end();
for (; b != e; ++b) {
const BuiltinType *BT = b->getType()->getAs<BuiltinType>();
if (!BT || !BT->isFloatingPoint())
break;
RTList.push_back(CGT.ConvertType(b->getType()));
}
if (b == e)
return llvm::StructType::get(getVMContext(), RTList,
RD->hasAttr<PackedAttr>());
RTList.clear();
}
}
CoerceToIntArgs(Size, RTList);
return llvm::StructType::get(getVMContext(), RTList);
}
ABIArgInfo MipsABIInfo::classifyReturnType(QualType RetTy) const {
uint64_t Size = getContext().getTypeSize(RetTy);
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
// O32 doesn't treat zero-sized structs differently from other structs.
// However, N32/N64 ignores zero sized return values.
if (!IsO32 && Size == 0)
return ABIArgInfo::getIgnore();
if (isAggregateTypeForABI(RetTy) || RetTy->isVectorType()) {
if (Size <= 128) {
if (RetTy->isAnyComplexType())
return ABIArgInfo::getDirect();
// O32 returns integer vectors in registers and N32/N64 returns all small
// aggregates in registers.
if (!IsO32 ||
(RetTy->isVectorType() && !RetTy->hasFloatingRepresentation())) {
ABIArgInfo ArgInfo =
ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
ArgInfo.setInReg(true);
return ArgInfo;
}
}
return getNaturalAlignIndirect(RetTy);
}
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
void MipsABIInfo::computeInfo(CGFunctionInfo &FI) const {
ABIArgInfo &RetInfo = FI.getReturnInfo();
if (!getCXXABI().classifyReturnType(FI))
RetInfo = classifyReturnType(FI.getReturnType());
// Check if a pointer to an aggregate is passed as a hidden argument.
uint64_t Offset = RetInfo.isIndirect() ? MinABIStackAlignInBytes : 0;
for (auto &I : FI.arguments())
I.info = classifyArgumentType(I.type, Offset);
}
Address MipsABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType OrigTy) const {
QualType Ty = OrigTy;
// Integer arguments are promoted to 32-bit on O32 and 64-bit on N32/N64.
// Pointers are also promoted in the same way but this only matters for N32.
unsigned SlotSizeInBits = IsO32 ? 32 : 64;
unsigned PtrWidth = getTarget().getPointerWidth(0);
bool DidPromote = false;
if ((Ty->isIntegerType() &&
getContext().getIntWidth(Ty) < SlotSizeInBits) ||
(Ty->isPointerType() && PtrWidth < SlotSizeInBits)) {
DidPromote = true;
Ty = getContext().getIntTypeForBitwidth(SlotSizeInBits,
Ty->isSignedIntegerType());
}
auto TyInfo = getContext().getTypeInfoInChars(Ty);
// The alignment of things in the argument area is never larger than
// StackAlignInBytes.
TyInfo.second =
std::min(TyInfo.second, CharUnits::fromQuantity(StackAlignInBytes));
// MinABIStackAlignInBytes is the size of argument slots on the stack.
CharUnits ArgSlotSize = CharUnits::fromQuantity(MinABIStackAlignInBytes);
Address Addr = emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*indirect*/ false,
TyInfo, ArgSlotSize, /*AllowHigherAlign*/ true);
// If there was a promotion, "unpromote" into a temporary.
// TODO: can we just use a pointer into a subset of the original slot?
if (DidPromote) {
Address Temp = CGF.CreateMemTemp(OrigTy, "vaarg.promotion-temp");
llvm::Value *Promoted = CGF.Builder.CreateLoad(Addr);
// Truncate down to the right width.
llvm::Type *IntTy = (OrigTy->isIntegerType() ? Temp.getElementType()
: CGF.IntPtrTy);
llvm::Value *V = CGF.Builder.CreateTrunc(Promoted, IntTy);
if (OrigTy->isPointerType())
V = CGF.Builder.CreateIntToPtr(V, Temp.getElementType());
CGF.Builder.CreateStore(V, Temp);
Addr = Temp;
}
return Addr;
}
bool MipsABIInfo::shouldSignExtUnsignedType(QualType Ty) const {
int TySize = getContext().getTypeSize(Ty);
// MIPS64 ABI requires unsigned 32 bit integers to be sign extended.
if (Ty->isUnsignedIntegerOrEnumerationType() && TySize == 32)
return true;
return false;
}
bool
MIPSTargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
// This information comes from gcc's implementation, which seems to
// as canonical as it gets.
// Everything on MIPS is 4 bytes. Double-precision FP registers
// are aliased to pairs of single-precision FP registers.
llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
// 0-31 are the general purpose registers, $0 - $31.
// 32-63 are the floating-point registers, $f0 - $f31.
// 64 and 65 are the multiply/divide registers, $hi and $lo.
// 66 is the (notional, I think) register for signal-handler return.
AssignToArrayRange(CGF.Builder, Address, Four8, 0, 65);
// 67-74 are the floating-point status registers, $fcc0 - $fcc7.
// They are one bit wide and ignored here.
// 80-111 are the coprocessor 0 registers, $c0r0 - $c0r31.
// (coprocessor 1 is the FP unit)
// 112-143 are the coprocessor 2 registers, $c2r0 - $c2r31.
// 144-175 are the coprocessor 3 registers, $c3r0 - $c3r31.
// 176-181 are the DSP accumulator registers.
AssignToArrayRange(CGF.Builder, Address, Four8, 80, 181);
return false;
}
//===----------------------------------------------------------------------===//
// TCE ABI Implementation (see http://tce.cs.tut.fi). Uses mostly the defaults.
// Currently subclassed only to implement custom OpenCL C function attribute
// handling.
//===----------------------------------------------------------------------===//
namespace {
class TCETargetCodeGenInfo : public DefaultTargetCodeGenInfo {
public:
TCETargetCodeGenInfo(CodeGenTypes &CGT)
: DefaultTargetCodeGenInfo(CGT) {}
void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const override;
};
void TCETargetCodeGenInfo::setTargetAttributes(
const Decl *D, llvm::GlobalValue *GV, CodeGen::CodeGenModule &M) const {
const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
if (!FD) return;
llvm::Function *F = cast<llvm::Function>(GV);
if (M.getLangOpts().OpenCL) {
if (FD->hasAttr<OpenCLKernelAttr>()) {
// OpenCL C Kernel functions are not subject to inlining
F->addFnAttr(llvm::Attribute::NoInline);
const ReqdWorkGroupSizeAttr *Attr = FD->getAttr<ReqdWorkGroupSizeAttr>();
if (Attr) {
// Convert the reqd_work_group_size() attributes to metadata.
llvm::LLVMContext &Context = F->getContext();
llvm::NamedMDNode *OpenCLMetadata =
M.getModule().getOrInsertNamedMetadata(
"opencl.kernel_wg_size_info");
SmallVector<llvm::Metadata *, 5> Operands;
Operands.push_back(llvm::ConstantAsMetadata::get(F));
Operands.push_back(
llvm::ConstantAsMetadata::get(llvm::Constant::getIntegerValue(
M.Int32Ty, llvm::APInt(32, Attr->getXDim()))));
Operands.push_back(
llvm::ConstantAsMetadata::get(llvm::Constant::getIntegerValue(
M.Int32Ty, llvm::APInt(32, Attr->getYDim()))));
Operands.push_back(
llvm::ConstantAsMetadata::get(llvm::Constant::getIntegerValue(
M.Int32Ty, llvm::APInt(32, Attr->getZDim()))));
// Add a boolean constant operand for "required" (true) or "hint"
// (false) for implementing the work_group_size_hint attr later.
// Currently always true as the hint is not yet implemented.
Operands.push_back(
llvm::ConstantAsMetadata::get(llvm::ConstantInt::getTrue(Context)));
OpenCLMetadata->addOperand(llvm::MDNode::get(Context, Operands));
}
}
}
}
}
//===----------------------------------------------------------------------===//
// Hexagon ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class HexagonABIInfo : public ABIInfo {
public:
HexagonABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
private:
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType RetTy) const;
void computeInfo(CGFunctionInfo &FI) const override;
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
};
class HexagonTargetCodeGenInfo : public TargetCodeGenInfo {
public:
HexagonTargetCodeGenInfo(CodeGenTypes &CGT)
:TargetCodeGenInfo(new HexagonABIInfo(CGT)) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
return 29;
}
};
}
void HexagonABIInfo::computeInfo(CGFunctionInfo &FI) const {
if (!getCXXABI().classifyReturnType(FI))
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (auto &I : FI.arguments())
I.info = classifyArgumentType(I.type);
}
ABIArgInfo HexagonABIInfo::classifyArgumentType(QualType Ty) const {
if (!isAggregateTypeForABI(Ty)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
// Ignore empty records.
if (isEmptyRecord(getContext(), Ty, true))
return ABIArgInfo::getIgnore();
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
uint64_t Size = getContext().getTypeSize(Ty);
if (Size > 64)
return getNaturalAlignIndirect(Ty, /*ByVal=*/true);
// Pass in the smallest viable integer type.
else if (Size > 32)
return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
else if (Size > 16)
return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
else if (Size > 8)
return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
else
return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
}
ABIArgInfo HexagonABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
// Large vector types should be returned via memory.
if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 64)
return getNaturalAlignIndirect(RetTy);
if (!isAggregateTypeForABI(RetTy)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
if (isEmptyRecord(getContext(), RetTy, true))
return ABIArgInfo::getIgnore();
// Aggregates <= 8 bytes are returned in r0; other aggregates
// are returned indirectly.
uint64_t Size = getContext().getTypeSize(RetTy);
if (Size <= 64) {
// Return in the smallest viable integer type.
if (Size <= 8)
return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
if (Size <= 16)
return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
if (Size <= 32)
return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
}
return getNaturalAlignIndirect(RetTy, /*ByVal=*/true);
}
Address HexagonABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
// FIXME: Someone needs to audit that this handle alignment correctly.
return emitVoidPtrVAArg(CGF, VAListAddr, Ty, /*indirect*/ false,
getContext().getTypeInfoInChars(Ty),
CharUnits::fromQuantity(4),
/*AllowHigherAlign*/ true);
}
//===----------------------------------------------------------------------===//
// AMDGPU ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class AMDGPUTargetCodeGenInfo : public TargetCodeGenInfo {
public:
AMDGPUTargetCodeGenInfo(CodeGenTypes &CGT)
: TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const override;
};
}
void AMDGPUTargetCodeGenInfo::setTargetAttributes(
const Decl *D,
llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const {
const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
if (!FD)
return;
if (const auto Attr = FD->getAttr<AMDGPUNumVGPRAttr>()) {
llvm::Function *F = cast<llvm::Function>(GV);
uint32_t NumVGPR = Attr->getNumVGPR();
if (NumVGPR != 0)
F->addFnAttr("amdgpu_num_vgpr", llvm::utostr(NumVGPR));
}
if (const auto Attr = FD->getAttr<AMDGPUNumSGPRAttr>()) {
llvm::Function *F = cast<llvm::Function>(GV);
unsigned NumSGPR = Attr->getNumSGPR();
if (NumSGPR != 0)
F->addFnAttr("amdgpu_num_sgpr", llvm::utostr(NumSGPR));
}
}
//===----------------------------------------------------------------------===//
// SPARC v9 ABI Implementation.
// Based on the SPARC Compliance Definition version 2.4.1.
//
// Function arguments a mapped to a nominal "parameter array" and promoted to
// registers depending on their type. Each argument occupies 8 or 16 bytes in
// the array, structs larger than 16 bytes are passed indirectly.
//
// One case requires special care:
//
// struct mixed {
// int i;
// float f;
// };
//
// When a struct mixed is passed by value, it only occupies 8 bytes in the
// parameter array, but the int is passed in an integer register, and the float
// is passed in a floating point register. This is represented as two arguments
// with the LLVM IR inreg attribute:
//
// declare void f(i32 inreg %i, float inreg %f)
//
// The code generator will only allocate 4 bytes from the parameter array for
// the inreg arguments. All other arguments are allocated a multiple of 8
// bytes.
//
namespace {
class SparcV9ABIInfo : public ABIInfo {
public:
SparcV9ABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
private:
ABIArgInfo classifyType(QualType RetTy, unsigned SizeLimit) const;
void computeInfo(CGFunctionInfo &FI) const override;
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
// Coercion type builder for structs passed in registers. The coercion type
// serves two purposes:
//
// 1. Pad structs to a multiple of 64 bits, so they are passed 'left-aligned'
// in registers.
// 2. Expose aligned floating point elements as first-level elements, so the
// code generator knows to pass them in floating point registers.
//
// We also compute the InReg flag which indicates that the struct contains
// aligned 32-bit floats.
//
struct CoerceBuilder {
llvm::LLVMContext &Context;
const llvm::DataLayout &DL;
SmallVector<llvm::Type*, 8> Elems;
uint64_t Size;
bool InReg;
CoerceBuilder(llvm::LLVMContext &c, const llvm::DataLayout &dl)
: Context(c), DL(dl), Size(0), InReg(false) {}
// Pad Elems with integers until Size is ToSize.
void pad(uint64_t ToSize) {
assert(ToSize >= Size && "Cannot remove elements");
if (ToSize == Size)
return;
// Finish the current 64-bit word.
uint64_t Aligned = llvm::RoundUpToAlignment(Size, 64);
if (Aligned > Size && Aligned <= ToSize) {
Elems.push_back(llvm::IntegerType::get(Context, Aligned - Size));
Size = Aligned;
}
// Add whole 64-bit words.
while (Size + 64 <= ToSize) {
Elems.push_back(llvm::Type::getInt64Ty(Context));
Size += 64;
}
// Final in-word padding.
if (Size < ToSize) {
Elems.push_back(llvm::IntegerType::get(Context, ToSize - Size));
Size = ToSize;
}
}
// Add a floating point element at Offset.
void addFloat(uint64_t Offset, llvm::Type *Ty, unsigned Bits) {
// Unaligned floats are treated as integers.
if (Offset % Bits)
return;
// The InReg flag is only required if there are any floats < 64 bits.
if (Bits < 64)
InReg = true;
pad(Offset);
Elems.push_back(Ty);
Size = Offset + Bits;
}
// Add a struct type to the coercion type, starting at Offset (in bits).
void addStruct(uint64_t Offset, llvm::StructType *StrTy) {
const llvm::StructLayout *Layout = DL.getStructLayout(StrTy);
for (unsigned i = 0, e = StrTy->getNumElements(); i != e; ++i) {
llvm::Type *ElemTy = StrTy->getElementType(i);
uint64_t ElemOffset = Offset + Layout->getElementOffsetInBits(i);
switch (ElemTy->getTypeID()) {
case llvm::Type::StructTyID:
addStruct(ElemOffset, cast<llvm::StructType>(ElemTy));
break;
case llvm::Type::FloatTyID:
addFloat(ElemOffset, ElemTy, 32);
break;
case llvm::Type::DoubleTyID:
addFloat(ElemOffset, ElemTy, 64);
break;
case llvm::Type::FP128TyID:
addFloat(ElemOffset, ElemTy, 128);
break;
case llvm::Type::PointerTyID:
if (ElemOffset % 64 == 0) {
pad(ElemOffset);
Elems.push_back(ElemTy);
Size += 64;
}
break;
default:
break;
}
}
}
// Check if Ty is a usable substitute for the coercion type.
bool isUsableType(llvm::StructType *Ty) const {
return llvm::makeArrayRef(Elems) == Ty->elements();
}
// Get the coercion type as a literal struct type.
llvm::Type *getType() const {
if (Elems.size() == 1)
return Elems.front();
else
return llvm::StructType::get(Context, Elems);
}
};
};
} // end anonymous namespace
ABIArgInfo
SparcV9ABIInfo::classifyType(QualType Ty, unsigned SizeLimit) const {
if (Ty->isVoidType())
return ABIArgInfo::getIgnore();
uint64_t Size = getContext().getTypeSize(Ty);
// Anything too big to fit in registers is passed with an explicit indirect
// pointer / sret pointer.
if (Size > SizeLimit)
return getNaturalAlignIndirect(Ty, /*ByVal=*/false);
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
// Integer types smaller than a register are extended.
if (Size < 64 && Ty->isIntegerType())
return ABIArgInfo::getExtend();
// Other non-aggregates go in registers.
if (!isAggregateTypeForABI(Ty))
return ABIArgInfo::getDirect();
// If a C++ object has either a non-trivial copy constructor or a non-trivial
// destructor, it is passed with an explicit indirect pointer / sret pointer.
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, getCXXABI()))
return getNaturalAlignIndirect(Ty, RAA == CGCXXABI::RAA_DirectInMemory);
// This is a small aggregate type that should be passed in registers.
// Build a coercion type from the LLVM struct type.
llvm::StructType *StrTy = dyn_cast<llvm::StructType>(CGT.ConvertType(Ty));
if (!StrTy)
return ABIArgInfo::getDirect();
CoerceBuilder CB(getVMContext(), getDataLayout());
CB.addStruct(0, StrTy);
CB.pad(llvm::RoundUpToAlignment(CB.DL.getTypeSizeInBits(StrTy), 64));
// Try to use the original type for coercion.
llvm::Type *CoerceTy = CB.isUsableType(StrTy) ? StrTy : CB.getType();
if (CB.InReg)
return ABIArgInfo::getDirectInReg(CoerceTy);
else
return ABIArgInfo::getDirect(CoerceTy);
}
Address SparcV9ABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
ABIArgInfo AI = classifyType(Ty, 16 * 8);
llvm::Type *ArgTy = CGT.ConvertType(Ty);
if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
AI.setCoerceToType(ArgTy);
CharUnits SlotSize = CharUnits::fromQuantity(8);
CGBuilderTy &Builder = CGF.Builder;
Address Addr(Builder.CreateLoad(VAListAddr, "ap.cur"), SlotSize);
llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
auto TypeInfo = getContext().getTypeInfoInChars(Ty);
Address ArgAddr = Address::invalid();
CharUnits Stride;
switch (AI.getKind()) {
case ABIArgInfo::Expand:
case ABIArgInfo::InAlloca:
llvm_unreachable("Unsupported ABI kind for va_arg");
case ABIArgInfo::Extend: {
Stride = SlotSize;
CharUnits Offset = SlotSize - TypeInfo.first;
ArgAddr = Builder.CreateConstInBoundsByteGEP(Addr, Offset, "extend");
break;
}
case ABIArgInfo::Direct: {
auto AllocSize = getDataLayout().getTypeAllocSize(AI.getCoerceToType());
Stride = CharUnits::fromQuantity(AllocSize).RoundUpToAlignment(SlotSize);
ArgAddr = Addr;
break;
}
case ABIArgInfo::Indirect:
Stride = SlotSize;
ArgAddr = Builder.CreateElementBitCast(Addr, ArgPtrTy, "indirect");
ArgAddr = Address(Builder.CreateLoad(ArgAddr, "indirect.arg"),
TypeInfo.second);
break;
case ABIArgInfo::Ignore:
return Address(llvm::UndefValue::get(ArgPtrTy), TypeInfo.second);
}
// Update VAList.
llvm::Value *NextPtr =
Builder.CreateConstInBoundsByteGEP(Addr.getPointer(), Stride, "ap.next");
Builder.CreateStore(NextPtr, VAListAddr);
return Builder.CreateBitCast(ArgAddr, ArgPtrTy, "arg.addr");
}
void SparcV9ABIInfo::computeInfo(CGFunctionInfo &FI) const {
FI.getReturnInfo() = classifyType(FI.getReturnType(), 32 * 8);
for (auto &I : FI.arguments())
I.info = classifyType(I.type, 16 * 8);
}
namespace {
class SparcV9TargetCodeGenInfo : public TargetCodeGenInfo {
public:
SparcV9TargetCodeGenInfo(CodeGenTypes &CGT)
: TargetCodeGenInfo(new SparcV9ABIInfo(CGT)) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
return 14;
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const override;
};
} // end anonymous namespace
bool
SparcV9TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
// This is calculated from the LLVM and GCC tables and verified
// against gcc output. AFAIK all ABIs use the same encoding.
CodeGen::CGBuilderTy &Builder = CGF.Builder;
llvm::IntegerType *i8 = CGF.Int8Ty;
llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
// 0-31: the 8-byte general-purpose registers
AssignToArrayRange(Builder, Address, Eight8, 0, 31);
// 32-63: f0-31, the 4-byte floating-point registers
AssignToArrayRange(Builder, Address, Four8, 32, 63);
// Y = 64
// PSR = 65
// WIM = 66
// TBR = 67
// PC = 68
// NPC = 69
// FSR = 70
// CSR = 71
AssignToArrayRange(Builder, Address, Eight8, 64, 71);
// 72-87: d0-15, the 8-byte floating-point registers
AssignToArrayRange(Builder, Address, Eight8, 72, 87);
return false;
}
//===----------------------------------------------------------------------===//
// XCore ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
/// A SmallStringEnc instance is used to build up the TypeString by passing
/// it by reference between functions that append to it.
typedef llvm::SmallString<128> SmallStringEnc;
/// TypeStringCache caches the meta encodings of Types.
///
/// The reason for caching TypeStrings is two fold:
/// 1. To cache a type's encoding for later uses;
/// 2. As a means to break recursive member type inclusion.
///
/// A cache Entry can have a Status of:
/// NonRecursive: The type encoding is not recursive;
/// Recursive: The type encoding is recursive;
/// Incomplete: An incomplete TypeString;
/// IncompleteUsed: An incomplete TypeString that has been used in a
/// Recursive type encoding.
///
/// A NonRecursive entry will have all of its sub-members expanded as fully
/// as possible. Whilst it may contain types which are recursive, the type
/// itself is not recursive and thus its encoding may be safely used whenever
/// the type is encountered.
///
/// A Recursive entry will have all of its sub-members expanded as fully as
/// possible. The type itself is recursive and it may contain other types which
/// are recursive. The Recursive encoding must not be used during the expansion
/// of a recursive type's recursive branch. For simplicity the code uses
/// IncompleteCount to reject all usage of Recursive encodings for member types.
///
/// An Incomplete entry is always a RecordType and only encodes its
/// identifier e.g. "s(S){}". Incomplete 'StubEnc' entries are ephemeral and
/// are placed into the cache during type expansion as a means to identify and
/// handle recursive inclusion of types as sub-members. If there is recursion
/// the entry becomes IncompleteUsed.
///
/// During the expansion of a RecordType's members:
///
/// If the cache contains a NonRecursive encoding for the member type, the
/// cached encoding is used;
///
/// If the cache contains a Recursive encoding for the member type, the
/// cached encoding is 'Swapped' out, as it may be incorrect, and...
///
/// If the member is a RecordType, an Incomplete encoding is placed into the
/// cache to break potential recursive inclusion of itself as a sub-member;
///
/// Once a member RecordType has been expanded, its temporary incomplete
/// entry is removed from the cache. If a Recursive encoding was swapped out
/// it is swapped back in;
///
/// If an incomplete entry is used to expand a sub-member, the incomplete
/// entry is marked as IncompleteUsed. The cache keeps count of how many
/// IncompleteUsed entries it currently contains in IncompleteUsedCount;
///
/// If a member's encoding is found to be a NonRecursive or Recursive viz:
/// IncompleteUsedCount==0, the member's encoding is added to the cache.
/// Else the member is part of a recursive type and thus the recursion has
/// been exited too soon for the encoding to be correct for the member.
///
class TypeStringCache {
enum Status {NonRecursive, Recursive, Incomplete, IncompleteUsed};
struct Entry {
std::string Str; // The encoded TypeString for the type.
enum Status State; // Information about the encoding in 'Str'.
std::string Swapped; // A temporary place holder for a Recursive encoding
// during the expansion of RecordType's members.
};
std::map<const IdentifierInfo *, struct Entry> Map;
unsigned IncompleteCount; // Number of Incomplete entries in the Map.
unsigned IncompleteUsedCount; // Number of IncompleteUsed entries in the Map.
public:
TypeStringCache() : IncompleteCount(0), IncompleteUsedCount(0) {}
void addIncomplete(const IdentifierInfo *ID, std::string StubEnc);
bool removeIncomplete(const IdentifierInfo *ID);
void addIfComplete(const IdentifierInfo *ID, StringRef Str,
bool IsRecursive);
StringRef lookupStr(const IdentifierInfo *ID);
};
/// TypeString encodings for enum & union fields must be order.
/// FieldEncoding is a helper for this ordering process.
class FieldEncoding {
bool HasName;
std::string Enc;
public:
FieldEncoding(bool b, SmallStringEnc &e) : HasName(b), Enc(e.c_str()) {}
StringRef str() {return Enc.c_str();}
bool operator<(const FieldEncoding &rhs) const {
if (HasName != rhs.HasName) return HasName;
return Enc < rhs.Enc;
}
};
class XCoreABIInfo : public DefaultABIInfo {
public:
XCoreABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
Address EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const override;
};
class XCoreTargetCodeGenInfo : public TargetCodeGenInfo {
mutable TypeStringCache TSC;
public:
XCoreTargetCodeGenInfo(CodeGenTypes &CGT)
:TargetCodeGenInfo(new XCoreABIInfo(CGT)) {}
void emitTargetMD(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const override;
};
} // End anonymous namespace.
Address XCoreABIInfo::EmitVAArg(CodeGenFunction &CGF, Address VAListAddr,
QualType Ty) const {
CGBuilderTy &Builder = CGF.Builder;
// Get the VAList.
CharUnits SlotSize = CharUnits::fromQuantity(4);
Address AP(Builder.CreateLoad(VAListAddr), SlotSize);
// Handle the argument.
ABIArgInfo AI = classifyArgumentType(Ty);
CharUnits TypeAlign = getContext().getTypeAlignInChars(Ty);
llvm::Type *ArgTy = CGT.ConvertType(Ty);
if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
AI.setCoerceToType(ArgTy);
llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
Address Val = Address::invalid();
CharUnits ArgSize = CharUnits::Zero();
switch (AI.getKind()) {
case ABIArgInfo::Expand:
case ABIArgInfo::InAlloca:
llvm_unreachable("Unsupported ABI kind for va_arg");
case ABIArgInfo::Ignore:
Val = Address(llvm::UndefValue::get(ArgPtrTy), TypeAlign);
ArgSize = CharUnits::Zero();
break;
case ABIArgInfo::Extend:
case ABIArgInfo::Direct:
Val = Builder.CreateBitCast(AP, ArgPtrTy);
ArgSize = CharUnits::fromQuantity(
getDataLayout().getTypeAllocSize(AI.getCoerceToType()));
ArgSize = ArgSize.RoundUpToAlignment(SlotSize);
break;
case ABIArgInfo::Indirect:
Val = Builder.CreateElementBitCast(AP, ArgPtrTy);
Val = Address(Builder.CreateLoad(Val), TypeAlign);
ArgSize = SlotSize;
break;
}
// Increment the VAList.
if (!ArgSize.isZero()) {
llvm::Value *APN =
Builder.CreateConstInBoundsByteGEP(AP.getPointer(), ArgSize);
Builder.CreateStore(APN, VAListAddr);
}
return Val;
}
/// During the expansion of a RecordType, an incomplete TypeString is placed
/// into the cache as a means to identify and break recursion.
/// If there is a Recursive encoding in the cache, it is swapped out and will
/// be reinserted by removeIncomplete().
/// All other types of encoding should have been used rather than arriving here.
void TypeStringCache::addIncomplete(const IdentifierInfo *ID,
std::string StubEnc) {
if (!ID)
return;
Entry &E = Map[ID];
assert( (E.Str.empty() || E.State == Recursive) &&
"Incorrectly use of addIncomplete");
assert(!StubEnc.empty() && "Passing an empty string to addIncomplete()");
E.Swapped.swap(E.Str); // swap out the Recursive
E.Str.swap(StubEnc);
E.State = Incomplete;
++IncompleteCount;
}
/// Once the RecordType has been expanded, the temporary incomplete TypeString
/// must be removed from the cache.
/// If a Recursive was swapped out by addIncomplete(), it will be replaced.
/// Returns true if the RecordType was defined recursively.
bool TypeStringCache::removeIncomplete(const IdentifierInfo *ID) {
if (!ID)
return false;
auto I = Map.find(ID);
assert(I != Map.end() && "Entry not present");
Entry &E = I->second;
assert( (E.State == Incomplete ||
E.State == IncompleteUsed) &&
"Entry must be an incomplete type");
bool IsRecursive = false;
if (E.State == IncompleteUsed) {
// We made use of our Incomplete encoding, thus we are recursive.
IsRecursive = true;
--IncompleteUsedCount;
}
if (E.Swapped.empty())
Map.erase(I);
else {
// Swap the Recursive back.
E.Swapped.swap(E.Str);
E.Swapped.clear();
E.State = Recursive;
}
--IncompleteCount;
return IsRecursive;
}
/// Add the encoded TypeString to the cache only if it is NonRecursive or
/// Recursive (viz: all sub-members were expanded as fully as possible).
void TypeStringCache::addIfComplete(const IdentifierInfo *ID, StringRef Str,
bool IsRecursive) {
if (!ID || IncompleteUsedCount)
return; // No key or it is is an incomplete sub-type so don't add.
Entry &E = Map[ID];
if (IsRecursive && !E.Str.empty()) {
assert(E.State==Recursive && E.Str.size() == Str.size() &&
"This is not the same Recursive entry");
// The parent container was not recursive after all, so we could have used
// this Recursive sub-member entry after all, but we assumed the worse when
// we started viz: IncompleteCount!=0.
return;
}
assert(E.Str.empty() && "Entry already present");
E.Str = Str.str();
E.State = IsRecursive? Recursive : NonRecursive;
}
/// Return a cached TypeString encoding for the ID. If there isn't one, or we
/// are recursively expanding a type (IncompleteCount != 0) and the cached
/// encoding is Recursive, return an empty StringRef.
StringRef TypeStringCache::lookupStr(const IdentifierInfo *ID) {
if (!ID)
return StringRef(); // We have no key.
auto I = Map.find(ID);
if (I == Map.end())
return StringRef(); // We have no encoding.
Entry &E = I->second;
if (E.State == Recursive && IncompleteCount)
return StringRef(); // We don't use Recursive encodings for member types.
if (E.State == Incomplete) {
// The incomplete type is being used to break out of recursion.
E.State = IncompleteUsed;
++IncompleteUsedCount;
}
return E.Str.c_str();
}
/// The XCore ABI includes a type information section that communicates symbol
/// type information to the linker. The linker uses this information to verify
/// safety/correctness of things such as array bound and pointers et al.
/// The ABI only requires C (and XC) language modules to emit TypeStrings.
/// This type information (TypeString) is emitted into meta data for all global
/// symbols: definitions, declarations, functions & variables.
///
/// The TypeString carries type, qualifier, name, size & value details.
/// Please see 'Tools Development Guide' section 2.16.2 for format details:
/// https://www.xmos.com/download/public/Tools-Development-Guide%28X9114A%29.pdf
/// The output is tested by test/CodeGen/xcore-stringtype.c.
///
static bool getTypeString(SmallStringEnc &Enc, const Decl *D,
CodeGen::CodeGenModule &CGM, TypeStringCache &TSC);
/// XCore uses emitTargetMD to emit TypeString metadata for global symbols.
void XCoreTargetCodeGenInfo::emitTargetMD(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const {
SmallStringEnc Enc;
if (getTypeString(Enc, D, CGM, TSC)) {
llvm::LLVMContext &Ctx = CGM.getModule().getContext();
llvm::SmallVector<llvm::Metadata *, 2> MDVals;
MDVals.push_back(llvm::ConstantAsMetadata::get(GV));
MDVals.push_back(llvm::MDString::get(Ctx, Enc.str()));
llvm::NamedMDNode *MD =
CGM.getModule().getOrInsertNamedMetadata("xcore.typestrings");
MD->addOperand(llvm::MDNode::get(Ctx, MDVals));
}
}
static bool appendType(SmallStringEnc &Enc, QualType QType,
const CodeGen::CodeGenModule &CGM,
TypeStringCache &TSC);
/// Helper function for appendRecordType().
/// Builds a SmallVector containing the encoded field types in declaration
/// order.
static bool extractFieldType(SmallVectorImpl<FieldEncoding> &FE,
const RecordDecl *RD,
const CodeGen::CodeGenModule &CGM,
TypeStringCache &TSC) {
for (const auto *Field : RD->fields()) {
SmallStringEnc Enc;
Enc += "m(";
Enc += Field->getName();
Enc += "){";
if (Field->isBitField()) {
Enc += "b(";
llvm::raw_svector_ostream OS(Enc);
OS << Field->getBitWidthValue(CGM.getContext());
Enc += ':';
}
if (!appendType(Enc, Field->getType(), CGM, TSC))
return false;
if (Field->isBitField())
Enc += ')';
Enc += '}';
FE.emplace_back(!Field->getName().empty(), Enc);
}
return true;
}
/// Appends structure and union types to Enc and adds encoding to cache.
/// Recursively calls appendType (via extractFieldType) for each field.
/// Union types have their fields ordered according to the ABI.
static bool appendRecordType(SmallStringEnc &Enc, const RecordType *RT,
const CodeGen::CodeGenModule &CGM,
TypeStringCache &TSC, const IdentifierInfo *ID) {
// Append the cached TypeString if we have one.
StringRef TypeString = TSC.lookupStr(ID);
if (!TypeString.empty()) {
Enc += TypeString;
return true;
}
// Start to emit an incomplete TypeString.
size_t Start = Enc.size();
Enc += (RT->isUnionType()? 'u' : 's');
Enc += '(';
if (ID)
Enc += ID->getName();
Enc += "){";
// We collect all encoded fields and order as necessary.
bool IsRecursive = false;
const RecordDecl *RD = RT->getDecl()->getDefinition();
if (RD && !RD->field_empty()) {
// An incomplete TypeString stub is placed in the cache for this RecordType
// so that recursive calls to this RecordType will use it whilst building a
// complete TypeString for this RecordType.
SmallVector<FieldEncoding, 16> FE;
std::string StubEnc(Enc.substr(Start).str());
StubEnc += '}'; // StubEnc now holds a valid incomplete TypeString.
TSC.addIncomplete(ID, std::move(StubEnc));
if (!extractFieldType(FE, RD, CGM, TSC)) {
(void) TSC.removeIncomplete(ID);
return false;
}
IsRecursive = TSC.removeIncomplete(ID);
// The ABI requires unions to be sorted but not structures.
// See FieldEncoding::operator< for sort algorithm.
if (RT->isUnionType())
std::sort(FE.begin(), FE.end());
// We can now complete the TypeString.
unsigned E = FE.size();
for (unsigned I = 0; I != E; ++I) {
if (I)
Enc += ',';
Enc += FE[I].str();
}
}
Enc += '}';
TSC.addIfComplete(ID, Enc.substr(Start), IsRecursive);
return true;
}
/// Appends enum types to Enc and adds the encoding to the cache.
static bool appendEnumType(SmallStringEnc &Enc, const EnumType *ET,
TypeStringCache &TSC,
const IdentifierInfo *ID) {
// Append the cached TypeString if we have one.
StringRef TypeString = TSC.lookupStr(ID);
if (!TypeString.empty()) {
Enc += TypeString;
return true;
}
size_t Start = Enc.size();
Enc += "e(";
if (ID)
Enc += ID->getName();
Enc += "){";
// We collect all encoded enumerations and order them alphanumerically.
if (const EnumDecl *ED = ET->getDecl()->getDefinition()) {
SmallVector<FieldEncoding, 16> FE;
for (auto I = ED->enumerator_begin(), E = ED->enumerator_end(); I != E;
++I) {
SmallStringEnc EnumEnc;
EnumEnc += "m(";
EnumEnc += I->getName();
EnumEnc += "){";
I->getInitVal().toString(EnumEnc);
EnumEnc += '}';
FE.push_back(FieldEncoding(!I->getName().empty(), EnumEnc));
}
std::sort(FE.begin(), FE.end());
unsigned E = FE.size();
for (unsigned I = 0; I != E; ++I) {
if (I)
Enc += ',';
Enc += FE[I].str();
}
}
Enc += '}';
TSC.addIfComplete(ID, Enc.substr(Start), false);
return true;
}
/// Appends type's qualifier to Enc.
/// This is done prior to appending the type's encoding.
static void appendQualifier(SmallStringEnc &Enc, QualType QT) {
// Qualifiers are emitted in alphabetical order.
static const char *const Table[]={"","c:","r:","cr:","v:","cv:","rv:","crv:"};
int Lookup = 0;
if (QT.isConstQualified())
Lookup += 1<<0;
if (QT.isRestrictQualified())
Lookup += 1<<1;
if (QT.isVolatileQualified())
Lookup += 1<<2;
Enc += Table[Lookup];
}
/// Appends built-in types to Enc.
static bool appendBuiltinType(SmallStringEnc &Enc, const BuiltinType *BT) {
const char *EncType;
switch (BT->getKind()) {
case BuiltinType::Void:
EncType = "0";
break;
case BuiltinType::Bool:
EncType = "b";
break;
case BuiltinType::Char_U:
EncType = "uc";
break;
case BuiltinType::UChar:
EncType = "uc";
break;
case BuiltinType::SChar:
EncType = "sc";
break;
case BuiltinType::UShort:
EncType = "us";
break;
case BuiltinType::Short:
EncType = "ss";
break;
case BuiltinType::UInt:
EncType = "ui";
break;
case BuiltinType::Int:
EncType = "si";
break;
case BuiltinType::ULong:
EncType = "ul";
break;
case BuiltinType::Long:
EncType = "sl";
break;
case BuiltinType::ULongLong:
EncType = "ull";
break;
case BuiltinType::LongLong:
EncType = "sll";
break;
case BuiltinType::Float:
EncType = "ft";
break;
case BuiltinType::Double:
EncType = "d";
break;
case BuiltinType::LongDouble:
EncType = "ld";
break;
default:
return false;
}
Enc += EncType;
return true;
}
/// Appends a pointer encoding to Enc before calling appendType for the pointee.
static bool appendPointerType(SmallStringEnc &Enc, const PointerType *PT,
const CodeGen::CodeGenModule &CGM,
TypeStringCache &TSC) {
Enc += "p(";
if (!appendType(Enc, PT->getPointeeType(), CGM, TSC))
return false;
Enc += ')';
return true;
}
/// Appends array encoding to Enc before calling appendType for the element.
static bool appendArrayType(SmallStringEnc &Enc, QualType QT,
const ArrayType *AT,
const CodeGen::CodeGenModule &CGM,
TypeStringCache &TSC, StringRef NoSizeEnc) {
if (AT->getSizeModifier() != ArrayType::Normal)
return false;
Enc += "a(";
if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
CAT->getSize().toStringUnsigned(Enc);
else
Enc += NoSizeEnc; // Global arrays use "*", otherwise it is "".
Enc += ':';
// The Qualifiers should be attached to the type rather than the array.
appendQualifier(Enc, QT);
if (!appendType(Enc, AT->getElementType(), CGM, TSC))
return false;
Enc += ')';
return true;
}
/// Appends a function encoding to Enc, calling appendType for the return type
/// and the arguments.
static bool appendFunctionType(SmallStringEnc &Enc, const FunctionType *FT,
const CodeGen::CodeGenModule &CGM,
TypeStringCache &TSC) {
Enc += "f{";
if (!appendType(Enc, FT->getReturnType(), CGM, TSC))
return false;
Enc += "}(";
if (const FunctionProtoType *FPT = FT->getAs<FunctionProtoType>()) {
// N.B. we are only interested in the adjusted param types.
auto I = FPT->param_type_begin();
auto E = FPT->param_type_end();
if (I != E) {
do {
if (!appendType(Enc, *I, CGM, TSC))
return false;
++I;
if (I != E)
Enc += ',';
} while (I != E);
if (FPT->isVariadic())
Enc += ",va";
} else {
if (FPT->isVariadic())
Enc += "va";
else
Enc += '0';
}
}
Enc += ')';
return true;
}
/// Handles the type's qualifier before dispatching a call to handle specific
/// type encodings.
static bool appendType(SmallStringEnc &Enc, QualType QType,
const CodeGen::CodeGenModule &CGM,
TypeStringCache &TSC) {
QualType QT = QType.getCanonicalType();
if (const ArrayType *AT = QT->getAsArrayTypeUnsafe())
// The Qualifiers should be attached to the type rather than the array.
// Thus we don't call appendQualifier() here.
return appendArrayType(Enc, QT, AT, CGM, TSC, "");
appendQualifier(Enc, QT);
if (const BuiltinType *BT = QT->getAs<BuiltinType>())
return appendBuiltinType(Enc, BT);
if (const PointerType *PT = QT->getAs<PointerType>())
return appendPointerType(Enc, PT, CGM, TSC);
if (const EnumType *ET = QT->getAs<EnumType>())
return appendEnumType(Enc, ET, TSC, QT.getBaseTypeIdentifier());
if (const RecordType *RT = QT->getAsStructureType())
return appendRecordType(Enc, RT, CGM, TSC, QT.getBaseTypeIdentifier());
if (const RecordType *RT = QT->getAsUnionType())
return appendRecordType(Enc, RT, CGM, TSC, QT.getBaseTypeIdentifier());
if (const FunctionType *FT = QT->getAs<FunctionType>())
return appendFunctionType(Enc, FT, CGM, TSC);
return false;
}
static bool getTypeString(SmallStringEnc &Enc, const Decl *D,
CodeGen::CodeGenModule &CGM, TypeStringCache &TSC) {
if (!D)
return false;
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
if (FD->getLanguageLinkage() != CLanguageLinkage)
return false;
return appendType(Enc, FD->getType(), CGM, TSC);
}
if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
if (VD->getLanguageLinkage() != CLanguageLinkage)
return false;
QualType QT = VD->getType().getCanonicalType();
if (const ArrayType *AT = QT->getAsArrayTypeUnsafe()) {
// Global ArrayTypes are given a size of '*' if the size is unknown.
// The Qualifiers should be attached to the type rather than the array.
// Thus we don't call appendQualifier() here.
return appendArrayType(Enc, QT, AT, CGM, TSC, "*");
}
return appendType(Enc, QT, CGM, TSC);
}
return false;
}
//===----------------------------------------------------------------------===//
// Driver code
//===----------------------------------------------------------------------===//
const llvm::Triple &CodeGenModule::getTriple() const {
return getTarget().getTriple();
}
bool CodeGenModule::supportsCOMDAT() const {
return !getTriple().isOSBinFormatMachO();
}
const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() {
if (TheTargetCodeGenInfo)
return *TheTargetCodeGenInfo;
const llvm::Triple &Triple = getTarget().getTriple();
switch (Triple.getArch()) {
default:
return *(TheTargetCodeGenInfo = new DefaultTargetCodeGenInfo(Types));
case llvm::Triple::le32:
return *(TheTargetCodeGenInfo = new PNaClTargetCodeGenInfo(Types));
case llvm::Triple::mips:
case llvm::Triple::mipsel:
if (Triple.getOS() == llvm::Triple::NaCl)
return *(TheTargetCodeGenInfo = new PNaClTargetCodeGenInfo(Types));
return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, true));
case llvm::Triple::mips64:
case llvm::Triple::mips64el:
return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, false));
case llvm::Triple::aarch64:
case llvm::Triple::aarch64_be: {
AArch64ABIInfo::ABIKind Kind = AArch64ABIInfo::AAPCS;
if (getTarget().getABI() == "darwinpcs")
Kind = AArch64ABIInfo::DarwinPCS;
return *(TheTargetCodeGenInfo = new AArch64TargetCodeGenInfo(Types, Kind));
}
case llvm::Triple::wasm32:
case llvm::Triple::wasm64:
return *(TheTargetCodeGenInfo = new WebAssemblyTargetCodeGenInfo(Types));
case llvm::Triple::arm:
case llvm::Triple::armeb:
case llvm::Triple::thumb:
case llvm::Triple::thumbeb:
{
if (Triple.getOS() == llvm::Triple::Win32) {
TheTargetCodeGenInfo =
new WindowsARMTargetCodeGenInfo(Types, ARMABIInfo::AAPCS_VFP);
return *TheTargetCodeGenInfo;
}
ARMABIInfo::ABIKind Kind = ARMABIInfo::AAPCS;
StringRef ABIStr = getTarget().getABI();
if (ABIStr == "apcs-gnu")
Kind = ARMABIInfo::APCS;
else if (ABIStr == "aapcs16")
Kind = ARMABIInfo::AAPCS16_VFP;
else if (CodeGenOpts.FloatABI == "hard" ||
(CodeGenOpts.FloatABI != "soft" &&
Triple.getEnvironment() == llvm::Triple::GNUEABIHF))
Kind = ARMABIInfo::AAPCS_VFP;
return *(TheTargetCodeGenInfo = new ARMTargetCodeGenInfo(Types, Kind));
}
case llvm::Triple::ppc:
return *(TheTargetCodeGenInfo =
new PPC32TargetCodeGenInfo(Types, CodeGenOpts.FloatABI == "soft"));
case llvm::Triple::ppc64:
if (Triple.isOSBinFormatELF()) {
PPC64_SVR4_ABIInfo::ABIKind Kind = PPC64_SVR4_ABIInfo::ELFv1;
if (getTarget().getABI() == "elfv2")
Kind = PPC64_SVR4_ABIInfo::ELFv2;
bool HasQPX = getTarget().getABI() == "elfv1-qpx";
return *(TheTargetCodeGenInfo =
new PPC64_SVR4_TargetCodeGenInfo(Types, Kind, HasQPX));
} else
return *(TheTargetCodeGenInfo = new PPC64TargetCodeGenInfo(Types));
case llvm::Triple::ppc64le: {
assert(Triple.isOSBinFormatELF() && "PPC64 LE non-ELF not supported!");
PPC64_SVR4_ABIInfo::ABIKind Kind = PPC64_SVR4_ABIInfo::ELFv2;
if (getTarget().getABI() == "elfv1" || getTarget().getABI() == "elfv1-qpx")
Kind = PPC64_SVR4_ABIInfo::ELFv1;
bool HasQPX = getTarget().getABI() == "elfv1-qpx";
return *(TheTargetCodeGenInfo =
new PPC64_SVR4_TargetCodeGenInfo(Types, Kind, HasQPX));
}
case llvm::Triple::nvptx:
case llvm::Triple::nvptx64:
return *(TheTargetCodeGenInfo = new NVPTXTargetCodeGenInfo(Types));
case llvm::Triple::msp430:
return *(TheTargetCodeGenInfo = new MSP430TargetCodeGenInfo(Types));
case llvm::Triple::systemz: {
bool HasVector = getTarget().getABI() == "vector";
return *(TheTargetCodeGenInfo = new SystemZTargetCodeGenInfo(Types,
HasVector));
}
case llvm::Triple::tce:
return *(TheTargetCodeGenInfo = new TCETargetCodeGenInfo(Types));
case llvm::Triple::x86: {
bool IsDarwinVectorABI = Triple.isOSDarwin();
bool RetSmallStructInRegABI =
X86_32TargetCodeGenInfo::isStructReturnInRegABI(Triple, CodeGenOpts);
bool IsWin32FloatStructABI = Triple.isOSWindows() && !Triple.isOSCygMing();
if (Triple.getOS() == llvm::Triple::Win32) {
return *(TheTargetCodeGenInfo = new WinX86_32TargetCodeGenInfo(
Types, IsDarwinVectorABI, RetSmallStructInRegABI,
IsWin32FloatStructABI, CodeGenOpts.NumRegisterParameters));
} else {
return *(TheTargetCodeGenInfo = new X86_32TargetCodeGenInfo(
Types, IsDarwinVectorABI, RetSmallStructInRegABI,
IsWin32FloatStructABI, CodeGenOpts.NumRegisterParameters,
CodeGenOpts.FloatABI == "soft"));
}
}
case llvm::Triple::x86_64: {
StringRef ABI = getTarget().getABI();
X86AVXABILevel AVXLevel = (ABI == "avx512" ? X86AVXABILevel::AVX512 :
ABI == "avx" ? X86AVXABILevel::AVX :
X86AVXABILevel::None);
switch (Triple.getOS()) {
case llvm::Triple::Win32:
return *(TheTargetCodeGenInfo =
new WinX86_64TargetCodeGenInfo(Types, AVXLevel));
case llvm::Triple::PS4:
return *(TheTargetCodeGenInfo =
new PS4TargetCodeGenInfo(Types, AVXLevel));
default:
return *(TheTargetCodeGenInfo =
new X86_64TargetCodeGenInfo(Types, AVXLevel));
}
}
case llvm::Triple::hexagon:
return *(TheTargetCodeGenInfo = new HexagonTargetCodeGenInfo(Types));
case llvm::Triple::r600:
return *(TheTargetCodeGenInfo = new AMDGPUTargetCodeGenInfo(Types));
case llvm::Triple::amdgcn:
return *(TheTargetCodeGenInfo = new AMDGPUTargetCodeGenInfo(Types));
case llvm::Triple::sparcv9:
return *(TheTargetCodeGenInfo = new SparcV9TargetCodeGenInfo(Types));
case llvm::Triple::xcore:
return *(TheTargetCodeGenInfo = new XCoreTargetCodeGenInfo(Types));
}
}