//===-- CGBlocks.h - state for LLVM CodeGen for blocks ----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This is the internal state used for llvm translation for block literals.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_LIB_CODEGEN_CGBLOCKS_H
#define LLVM_CLANG_LIB_CODEGEN_CGBLOCKS_H
#include "CGBuilder.h"
#include "CGCall.h"
#include "CGValue.h"
#include "CodeGenFunction.h"
#include "CodeGenTypes.h"
#include "clang/AST/CharUnits.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/ExprObjC.h"
#include "clang/AST/Type.h"
#include "clang/Basic/TargetInfo.h"
#include "llvm/IR/Module.h"
namespace llvm {
class Module;
class Constant;
class Function;
class GlobalValue;
class DataLayout;
class FunctionType;
class PointerType;
class Value;
class LLVMContext;
}
namespace clang {
namespace CodeGen {
class CodeGenModule;
class CGBlockInfo;
// Flags stored in __block variables.
enum BlockByrefFlags {
BLOCK_BYREF_HAS_COPY_DISPOSE = (1 << 25), // compiler
BLOCK_BYREF_LAYOUT_MASK = (0xF << 28), // compiler
BLOCK_BYREF_LAYOUT_EXTENDED = (1 << 28),
BLOCK_BYREF_LAYOUT_NON_OBJECT = (2 << 28),
BLOCK_BYREF_LAYOUT_STRONG = (3 << 28),
BLOCK_BYREF_LAYOUT_WEAK = (4 << 28),
BLOCK_BYREF_LAYOUT_UNRETAINED = (5 << 28)
};
enum BlockLiteralFlags {
BLOCK_HAS_COPY_DISPOSE = (1 << 25),
BLOCK_HAS_CXX_OBJ = (1 << 26),
BLOCK_IS_GLOBAL = (1 << 28),
BLOCK_USE_STRET = (1 << 29),
BLOCK_HAS_SIGNATURE = (1 << 30),
BLOCK_HAS_EXTENDED_LAYOUT = (1 << 31)
};
class BlockFlags {
uint32_t flags;
public:
BlockFlags(uint32_t flags) : flags(flags) {}
BlockFlags() : flags(0) {}
BlockFlags(BlockLiteralFlags flag) : flags(flag) {}
BlockFlags(BlockByrefFlags flag) : flags(flag) {}
uint32_t getBitMask() const { return flags; }
bool empty() const { return flags == 0; }
friend BlockFlags operator|(BlockFlags l, BlockFlags r) {
return BlockFlags(l.flags | r.flags);
}
friend BlockFlags &operator|=(BlockFlags &l, BlockFlags r) {
l.flags |= r.flags;
return l;
}
friend bool operator&(BlockFlags l, BlockFlags r) {
return (l.flags & r.flags);
}
bool operator==(BlockFlags r) {
return (flags == r.flags);
}
};
inline BlockFlags operator|(BlockLiteralFlags l, BlockLiteralFlags r) {
return BlockFlags(l) | BlockFlags(r);
}
enum BlockFieldFlag_t {
BLOCK_FIELD_IS_OBJECT = 0x03, /* id, NSObject, __attribute__((NSObject)),
block, ... */
BLOCK_FIELD_IS_BLOCK = 0x07, /* a block variable */
BLOCK_FIELD_IS_BYREF = 0x08, /* the on stack structure holding the __block
variable */
BLOCK_FIELD_IS_WEAK = 0x10, /* declared __weak, only used in byref copy
helpers */
BLOCK_FIELD_IS_ARC = 0x40, /* field has ARC-specific semantics */
BLOCK_BYREF_CALLER = 128, /* called from __block (byref) copy/dispose
support routines */
BLOCK_BYREF_CURRENT_MAX = 256
};
class BlockFieldFlags {
uint32_t flags;
BlockFieldFlags(uint32_t flags) : flags(flags) {}
public:
BlockFieldFlags() : flags(0) {}
BlockFieldFlags(BlockFieldFlag_t flag) : flags(flag) {}
uint32_t getBitMask() const { return flags; }
bool empty() const { return flags == 0; }
/// Answers whether the flags indicate that this field is an object
/// or block pointer that requires _Block_object_assign/dispose.
bool isSpecialPointer() const { return flags & BLOCK_FIELD_IS_OBJECT; }
friend BlockFieldFlags operator|(BlockFieldFlags l, BlockFieldFlags r) {
return BlockFieldFlags(l.flags | r.flags);
}
friend BlockFieldFlags &operator|=(BlockFieldFlags &l, BlockFieldFlags r) {
l.flags |= r.flags;
return l;
}
friend bool operator&(BlockFieldFlags l, BlockFieldFlags r) {
return (l.flags & r.flags);
}
};
inline BlockFieldFlags operator|(BlockFieldFlag_t l, BlockFieldFlag_t r) {
return BlockFieldFlags(l) | BlockFieldFlags(r);
}
/// Information about the layout of a __block variable.
class BlockByrefInfo {
public:
llvm::StructType *Type;
unsigned FieldIndex;
CharUnits ByrefAlignment;
CharUnits FieldOffset;
};
/// CGBlockInfo - Information to generate a block literal.
class CGBlockInfo {
public:
/// Name - The name of the block, kindof.
StringRef Name;
/// The field index of 'this' within the block, if there is one.
unsigned CXXThisIndex;
class Capture {
uintptr_t Data;
EHScopeStack::stable_iterator Cleanup;
CharUnits::QuantityType Offset;
public:
bool isIndex() const { return (Data & 1) != 0; }
bool isConstant() const { return !isIndex(); }
unsigned getIndex() const {
assert(isIndex());
return Data >> 1;
}
CharUnits getOffset() const {
assert(isIndex());
return CharUnits::fromQuantity(Offset);
}
EHScopeStack::stable_iterator getCleanup() const {
assert(isIndex());
return Cleanup;
}
void setCleanup(EHScopeStack::stable_iterator cleanup) {
assert(isIndex());
Cleanup = cleanup;
}
llvm::Value *getConstant() const {
assert(isConstant());
return reinterpret_cast<llvm::Value*>(Data);
}
static Capture makeIndex(unsigned index, CharUnits offset) {
Capture v;
v.Data = (index << 1) | 1;
v.Offset = offset.getQuantity();
return v;
}
static Capture makeConstant(llvm::Value *value) {
Capture v;
v.Data = reinterpret_cast<uintptr_t>(value);
return v;
}
};
/// CanBeGlobal - True if the block can be global, i.e. it has
/// no non-constant captures.
bool CanBeGlobal : 1;
/// True if the block needs a custom copy or dispose function.
bool NeedsCopyDispose : 1;
/// HasCXXObject - True if the block's custom copy/dispose functions
/// need to be run even in GC mode.
bool HasCXXObject : 1;
/// UsesStret : True if the block uses an stret return. Mutable
/// because it gets set later in the block-creation process.
mutable bool UsesStret : 1;
/// HasCapturedVariableLayout : True if block has captured variables
/// and their layout meta-data has been generated.
bool HasCapturedVariableLayout : 1;
/// The mapping of allocated indexes within the block.
llvm::DenseMap<const VarDecl*, Capture> Captures;
Address LocalAddress;
llvm::StructType *StructureType;
const BlockDecl *Block;
const BlockExpr *BlockExpression;
CharUnits BlockSize;
CharUnits BlockAlign;
CharUnits CXXThisOffset;
// Offset of the gap caused by block header having a smaller
// alignment than the alignment of the block descriptor. This
// is the gap offset before the first capturued field.
CharUnits BlockHeaderForcedGapOffset;
// Gap size caused by aligning first field after block header.
// This could be zero if no forced alignment is required.
CharUnits BlockHeaderForcedGapSize;
/// An instruction which dominates the full-expression that the
/// block is inside.
llvm::Instruction *DominatingIP;
/// The next block in the block-info chain. Invalid if this block
/// info is not part of the CGF's block-info chain, which is true
/// if it corresponds to a global block or a block whose expression
/// has been encountered.
CGBlockInfo *NextBlockInfo;
const Capture &getCapture(const VarDecl *var) const {
return const_cast<CGBlockInfo*>(this)->getCapture(var);
}
Capture &getCapture(const VarDecl *var) {
llvm::DenseMap<const VarDecl*, Capture>::iterator
it = Captures.find(var);
assert(it != Captures.end() && "no entry for variable!");
return it->second;
}
const BlockDecl *getBlockDecl() const { return Block; }
const BlockExpr *getBlockExpr() const {
assert(BlockExpression);
assert(BlockExpression->getBlockDecl() == Block);
return BlockExpression;
}
CGBlockInfo(const BlockDecl *blockDecl, StringRef Name);
};
} // end namespace CodeGen
} // end namespace clang
#endif