//===- TargetTransformInfo.h ------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
/// \file
/// This pass exposes codegen information to IR-level passes. Every
/// transformation that uses codegen information is broken into three parts:
/// 1. The IR-level analysis pass.
/// 2. The IR-level transformation interface which provides the needed
/// information.
/// 3. Codegen-level implementation which uses target-specific hooks.
///
/// This file defines #2, which is the interface that IR-level transformations
/// use for querying the codegen.
///
//===----------------------------------------------------------------------===//
#ifndef LLVM_ANALYSIS_TARGETTRANSFORMINFO_H
#define LLVM_ANALYSIS_TARGETTRANSFORMINFO_H
#include "llvm/ADT/Optional.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/PassManager.h"
#include "llvm/Pass.h"
#include "llvm/Support/AtomicOrdering.h"
#include "llvm/Support/DataTypes.h"
#include <functional>
namespace llvm {
namespace Intrinsic {
enum ID : unsigned;
}
class Function;
class GlobalValue;
class IntrinsicInst;
class LoadInst;
class Loop;
class SCEV;
class ScalarEvolution;
class StoreInst;
class SwitchInst;
class Type;
class User;
class Value;
/// Information about a load/store intrinsic defined by the target.
struct MemIntrinsicInfo {
/// This is the pointer that the intrinsic is loading from or storing to.
/// If this is non-null, then analysis/optimization passes can assume that
/// this intrinsic is functionally equivalent to a load/store from this
/// pointer.
Value *PtrVal = nullptr;
// Ordering for atomic operations.
AtomicOrdering Ordering = AtomicOrdering::NotAtomic;
// Same Id is set by the target for corresponding load/store intrinsics.
unsigned short MatchingId = 0;
bool ReadMem = false;
bool WriteMem = false;
bool IsVolatile = false;
bool isUnordered() const {
return (Ordering == AtomicOrdering::NotAtomic ||
Ordering == AtomicOrdering::Unordered) && !IsVolatile;
}
};
/// This pass provides access to the codegen interfaces that are needed
/// for IR-level transformations.
class TargetTransformInfo {
public:
/// Construct a TTI object using a type implementing the \c Concept
/// API below.
///
/// This is used by targets to construct a TTI wrapping their target-specific
/// implementaion that encodes appropriate costs for their target.
template <typename T> TargetTransformInfo(T Impl);
/// Construct a baseline TTI object using a minimal implementation of
/// the \c Concept API below.
///
/// The TTI implementation will reflect the information in the DataLayout
/// provided if non-null.
explicit TargetTransformInfo(const DataLayout &DL);
// Provide move semantics.
TargetTransformInfo(TargetTransformInfo &&Arg);
TargetTransformInfo &operator=(TargetTransformInfo &&RHS);
// We need to define the destructor out-of-line to define our sub-classes
// out-of-line.
~TargetTransformInfo();
/// Handle the invalidation of this information.
///
/// When used as a result of \c TargetIRAnalysis this method will be called
/// when the function this was computed for changes. When it returns false,
/// the information is preserved across those changes.
bool invalidate(Function &, const PreservedAnalyses &,
FunctionAnalysisManager::Invalidator &) {
// FIXME: We should probably in some way ensure that the subtarget
// information for a function hasn't changed.
return false;
}
/// \name Generic Target Information
/// @{
/// The kind of cost model.
///
/// There are several different cost models that can be customized by the
/// target. The normalization of each cost model may be target specific.
enum TargetCostKind {
TCK_RecipThroughput, ///< Reciprocal throughput.
TCK_Latency, ///< The latency of instruction.
TCK_CodeSize ///< Instruction code size.
};
/// Query the cost of a specified instruction.
///
/// Clients should use this interface to query the cost of an existing
/// instruction. The instruction must have a valid parent (basic block).
///
/// Note, this method does not cache the cost calculation and it
/// can be expensive in some cases.
int getInstructionCost(const Instruction *I, enum TargetCostKind kind) const {
switch (kind){
case TCK_RecipThroughput:
return getInstructionThroughput(I);
case TCK_Latency:
return getInstructionLatency(I);
case TCK_CodeSize:
return getUserCost(I);
}
llvm_unreachable("Unknown instruction cost kind");
}
/// Underlying constants for 'cost' values in this interface.
///
/// Many APIs in this interface return a cost. This enum defines the
/// fundamental values that should be used to interpret (and produce) those
/// costs. The costs are returned as an int rather than a member of this
/// enumeration because it is expected that the cost of one IR instruction
/// may have a multiplicative factor to it or otherwise won't fit directly
/// into the enum. Moreover, it is common to sum or average costs which works
/// better as simple integral values. Thus this enum only provides constants.
/// Also note that the returned costs are signed integers to make it natural
/// to add, subtract, and test with zero (a common boundary condition). It is
/// not expected that 2^32 is a realistic cost to be modeling at any point.
///
/// Note that these costs should usually reflect the intersection of code-size
/// cost and execution cost. A free instruction is typically one that folds
/// into another instruction. For example, reg-to-reg moves can often be
/// skipped by renaming the registers in the CPU, but they still are encoded
/// and thus wouldn't be considered 'free' here.
enum TargetCostConstants {
TCC_Free = 0, ///< Expected to fold away in lowering.
TCC_Basic = 1, ///< The cost of a typical 'add' instruction.
TCC_Expensive = 4 ///< The cost of a 'div' instruction on x86.
};
/// Estimate the cost of a specific operation when lowered.
///
/// Note that this is designed to work on an arbitrary synthetic opcode, and
/// thus work for hypothetical queries before an instruction has even been
/// formed. However, this does *not* work for GEPs, and must not be called
/// for a GEP instruction. Instead, use the dedicated getGEPCost interface as
/// analyzing a GEP's cost required more information.
///
/// Typically only the result type is required, and the operand type can be
/// omitted. However, if the opcode is one of the cast instructions, the
/// operand type is required.
///
/// The returned cost is defined in terms of \c TargetCostConstants, see its
/// comments for a detailed explanation of the cost values.
int getOperationCost(unsigned Opcode, Type *Ty, Type *OpTy = nullptr) const;
/// Estimate the cost of a GEP operation when lowered.
///
/// The contract for this function is the same as \c getOperationCost except
/// that it supports an interface that provides extra information specific to
/// the GEP operation.
int getGEPCost(Type *PointeeType, const Value *Ptr,
ArrayRef<const Value *> Operands) const;
/// Estimate the cost of a EXT operation when lowered.
///
/// The contract for this function is the same as \c getOperationCost except
/// that it supports an interface that provides extra information specific to
/// the EXT operation.
int getExtCost(const Instruction *I, const Value *Src) const;
/// Estimate the cost of a function call when lowered.
///
/// The contract for this is the same as \c getOperationCost except that it
/// supports an interface that provides extra information specific to call
/// instructions.
///
/// This is the most basic query for estimating call cost: it only knows the
/// function type and (potentially) the number of arguments at the call site.
/// The latter is only interesting for varargs function types.
int getCallCost(FunctionType *FTy, int NumArgs = -1) const;
/// Estimate the cost of calling a specific function when lowered.
///
/// This overload adds the ability to reason about the particular function
/// being called in the event it is a library call with special lowering.
int getCallCost(const Function *F, int NumArgs = -1) const;
/// Estimate the cost of calling a specific function when lowered.
///
/// This overload allows specifying a set of candidate argument values.
int getCallCost(const Function *F, ArrayRef<const Value *> Arguments) const;
/// \returns A value by which our inlining threshold should be multiplied.
/// This is primarily used to bump up the inlining threshold wholesale on
/// targets where calls are unusually expensive.
///
/// TODO: This is a rather blunt instrument. Perhaps altering the costs of
/// individual classes of instructions would be better.
unsigned getInliningThresholdMultiplier() const;
/// Estimate the cost of an intrinsic when lowered.
///
/// Mirrors the \c getCallCost method but uses an intrinsic identifier.
int getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
ArrayRef<Type *> ParamTys) const;
/// Estimate the cost of an intrinsic when lowered.
///
/// Mirrors the \c getCallCost method but uses an intrinsic identifier.
int getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
ArrayRef<const Value *> Arguments) const;
/// \return The estimated number of case clusters when lowering \p 'SI'.
/// \p JTSize Set a jump table size only when \p SI is suitable for a jump
/// table.
unsigned getEstimatedNumberOfCaseClusters(const SwitchInst &SI,
unsigned &JTSize) const;
/// Estimate the cost of a given IR user when lowered.
///
/// This can estimate the cost of either a ConstantExpr or Instruction when
/// lowered. It has two primary advantages over the \c getOperationCost and
/// \c getGEPCost above, and one significant disadvantage: it can only be
/// used when the IR construct has already been formed.
///
/// The advantages are that it can inspect the SSA use graph to reason more
/// accurately about the cost. For example, all-constant-GEPs can often be
/// folded into a load or other instruction, but if they are used in some
/// other context they may not be folded. This routine can distinguish such
/// cases.
///
/// \p Operands is a list of operands which can be a result of transformations
/// of the current operands. The number of the operands on the list must equal
/// to the number of the current operands the IR user has. Their order on the
/// list must be the same as the order of the current operands the IR user
/// has.
///
/// The returned cost is defined in terms of \c TargetCostConstants, see its
/// comments for a detailed explanation of the cost values.
int getUserCost(const User *U, ArrayRef<const Value *> Operands) const;
/// This is a helper function which calls the two-argument getUserCost
/// with \p Operands which are the current operands U has.
int getUserCost(const User *U) const {
SmallVector<const Value *, 4> Operands(U->value_op_begin(),
U->value_op_end());
return getUserCost(U, Operands);
}
/// Return true if branch divergence exists.
///
/// Branch divergence has a significantly negative impact on GPU performance
/// when threads in the same wavefront take different paths due to conditional
/// branches.
bool hasBranchDivergence() const;
/// Returns whether V is a source of divergence.
///
/// This function provides the target-dependent information for
/// the target-independent LegacyDivergenceAnalysis. LegacyDivergenceAnalysis first
/// builds the dependency graph, and then runs the reachability algorithm
/// starting with the sources of divergence.
bool isSourceOfDivergence(const Value *V) const;
// Returns true for the target specific
// set of operations which produce uniform result
// even taking non-unform arguments
bool isAlwaysUniform(const Value *V) const;
/// Returns the address space ID for a target's 'flat' address space. Note
/// this is not necessarily the same as addrspace(0), which LLVM sometimes
/// refers to as the generic address space. The flat address space is a
/// generic address space that can be used access multiple segments of memory
/// with different address spaces. Access of a memory location through a
/// pointer with this address space is expected to be legal but slower
/// compared to the same memory location accessed through a pointer with a
/// different address space.
//
/// This is for targets with different pointer representations which can
/// be converted with the addrspacecast instruction. If a pointer is converted
/// to this address space, optimizations should attempt to replace the access
/// with the source address space.
///
/// \returns ~0u if the target does not have such a flat address space to
/// optimize away.
unsigned getFlatAddressSpace() const;
/// Test whether calls to a function lower to actual program function
/// calls.
///
/// The idea is to test whether the program is likely to require a 'call'
/// instruction or equivalent in order to call the given function.
///
/// FIXME: It's not clear that this is a good or useful query API. Client's
/// should probably move to simpler cost metrics using the above.
/// Alternatively, we could split the cost interface into distinct code-size
/// and execution-speed costs. This would allow modelling the core of this
/// query more accurately as a call is a single small instruction, but
/// incurs significant execution cost.
bool isLoweredToCall(const Function *F) const;
struct LSRCost {
/// TODO: Some of these could be merged. Also, a lexical ordering
/// isn't always optimal.
unsigned Insns;
unsigned NumRegs;
unsigned AddRecCost;
unsigned NumIVMuls;
unsigned NumBaseAdds;
unsigned ImmCost;
unsigned SetupCost;
unsigned ScaleCost;
};
/// Parameters that control the generic loop unrolling transformation.
struct UnrollingPreferences {
/// The cost threshold for the unrolled loop. Should be relative to the
/// getUserCost values returned by this API, and the expectation is that
/// the unrolled loop's instructions when run through that interface should
/// not exceed this cost. However, this is only an estimate. Also, specific
/// loops may be unrolled even with a cost above this threshold if deemed
/// profitable. Set this to UINT_MAX to disable the loop body cost
/// restriction.
unsigned Threshold;
/// If complete unrolling will reduce the cost of the loop, we will boost
/// the Threshold by a certain percent to allow more aggressive complete
/// unrolling. This value provides the maximum boost percentage that we
/// can apply to Threshold (The value should be no less than 100).
/// BoostedThreshold = Threshold * min(RolledCost / UnrolledCost,
/// MaxPercentThresholdBoost / 100)
/// E.g. if complete unrolling reduces the loop execution time by 50%
/// then we boost the threshold by the factor of 2x. If unrolling is not
/// expected to reduce the running time, then we do not increase the
/// threshold.
unsigned MaxPercentThresholdBoost;
/// The cost threshold for the unrolled loop when optimizing for size (set
/// to UINT_MAX to disable).
unsigned OptSizeThreshold;
/// The cost threshold for the unrolled loop, like Threshold, but used
/// for partial/runtime unrolling (set to UINT_MAX to disable).
unsigned PartialThreshold;
/// The cost threshold for the unrolled loop when optimizing for size, like
/// OptSizeThreshold, but used for partial/runtime unrolling (set to
/// UINT_MAX to disable).
unsigned PartialOptSizeThreshold;
/// A forced unrolling factor (the number of concatenated bodies of the
/// original loop in the unrolled loop body). When set to 0, the unrolling
/// transformation will select an unrolling factor based on the current cost
/// threshold and other factors.
unsigned Count;
/// A forced peeling factor (the number of bodied of the original loop
/// that should be peeled off before the loop body). When set to 0, the
/// unrolling transformation will select a peeling factor based on profile
/// information and other factors.
unsigned PeelCount;
/// Default unroll count for loops with run-time trip count.
unsigned DefaultUnrollRuntimeCount;
// Set the maximum unrolling factor. The unrolling factor may be selected
// using the appropriate cost threshold, but may not exceed this number
// (set to UINT_MAX to disable). This does not apply in cases where the
// loop is being fully unrolled.
unsigned MaxCount;
/// Set the maximum unrolling factor for full unrolling. Like MaxCount, but
/// applies even if full unrolling is selected. This allows a target to fall
/// back to Partial unrolling if full unrolling is above FullUnrollMaxCount.
unsigned FullUnrollMaxCount;
// Represents number of instructions optimized when "back edge"
// becomes "fall through" in unrolled loop.
// For now we count a conditional branch on a backedge and a comparison
// feeding it.
unsigned BEInsns;
/// Allow partial unrolling (unrolling of loops to expand the size of the
/// loop body, not only to eliminate small constant-trip-count loops).
bool Partial;
/// Allow runtime unrolling (unrolling of loops to expand the size of the
/// loop body even when the number of loop iterations is not known at
/// compile time).
bool Runtime;
/// Allow generation of a loop remainder (extra iterations after unroll).
bool AllowRemainder;
/// Allow emitting expensive instructions (such as divisions) when computing
/// the trip count of a loop for runtime unrolling.
bool AllowExpensiveTripCount;
/// Apply loop unroll on any kind of loop
/// (mainly to loops that fail runtime unrolling).
bool Force;
/// Allow using trip count upper bound to unroll loops.
bool UpperBound;
/// Allow peeling off loop iterations for loops with low dynamic tripcount.
bool AllowPeeling;
/// Allow unrolling of all the iterations of the runtime loop remainder.
bool UnrollRemainder;
/// Allow unroll and jam. Used to enable unroll and jam for the target.
bool UnrollAndJam;
/// Threshold for unroll and jam, for inner loop size. The 'Threshold'
/// value above is used during unroll and jam for the outer loop size.
/// This value is used in the same manner to limit the size of the inner
/// loop.
unsigned UnrollAndJamInnerLoopThreshold;
};
/// Get target-customized preferences for the generic loop unrolling
/// transformation. The caller will initialize UP with the current
/// target-independent defaults.
void getUnrollingPreferences(Loop *L, ScalarEvolution &,
UnrollingPreferences &UP) const;
/// @}
/// \name Scalar Target Information
/// @{
/// Flags indicating the kind of support for population count.
///
/// Compared to the SW implementation, HW support is supposed to
/// significantly boost the performance when the population is dense, and it
/// may or may not degrade performance if the population is sparse. A HW
/// support is considered as "Fast" if it can outperform, or is on a par
/// with, SW implementation when the population is sparse; otherwise, it is
/// considered as "Slow".
enum PopcntSupportKind { PSK_Software, PSK_SlowHardware, PSK_FastHardware };
/// Return true if the specified immediate is legal add immediate, that
/// is the target has add instructions which can add a register with the
/// immediate without having to materialize the immediate into a register.
bool isLegalAddImmediate(int64_t Imm) const;
/// Return true if the specified immediate is legal icmp immediate,
/// that is the target has icmp instructions which can compare a register
/// against the immediate without having to materialize the immediate into a
/// register.
bool isLegalICmpImmediate(int64_t Imm) const;
/// Return true if the addressing mode represented by AM is legal for
/// this target, for a load/store of the specified type.
/// The type may be VoidTy, in which case only return true if the addressing
/// mode is legal for a load/store of any legal type.
/// If target returns true in LSRWithInstrQueries(), I may be valid.
/// TODO: Handle pre/postinc as well.
bool isLegalAddressingMode(Type *Ty, GlobalValue *BaseGV, int64_t BaseOffset,
bool HasBaseReg, int64_t Scale,
unsigned AddrSpace = 0,
Instruction *I = nullptr) const;
/// Return true if LSR cost of C1 is lower than C1.
bool isLSRCostLess(TargetTransformInfo::LSRCost &C1,
TargetTransformInfo::LSRCost &C2) const;
/// Return true if the target can fuse a compare and branch.
/// Loop-strength-reduction (LSR) uses that knowledge to adjust its cost
/// calculation for the instructions in a loop.
bool canMacroFuseCmp() const;
/// \return True is LSR should make efforts to create/preserve post-inc
/// addressing mode expressions.
bool shouldFavorPostInc() const;
/// Return true if the target supports masked load/store
/// AVX2 and AVX-512 targets allow masks for consecutive load and store
bool isLegalMaskedStore(Type *DataType) const;
bool isLegalMaskedLoad(Type *DataType) const;
/// Return true if the target supports masked gather/scatter
/// AVX-512 fully supports gather and scatter for vectors with 32 and 64
/// bits scalar type.
bool isLegalMaskedScatter(Type *DataType) const;
bool isLegalMaskedGather(Type *DataType) const;
/// Return true if the target has a unified operation to calculate division
/// and remainder. If so, the additional implicit multiplication and
/// subtraction required to calculate a remainder from division are free. This
/// can enable more aggressive transformations for division and remainder than
/// would typically be allowed using throughput or size cost models.
bool hasDivRemOp(Type *DataType, bool IsSigned) const;
/// Return true if the given instruction (assumed to be a memory access
/// instruction) has a volatile variant. If that's the case then we can avoid
/// addrspacecast to generic AS for volatile loads/stores. Default
/// implementation returns false, which prevents address space inference for
/// volatile loads/stores.
bool hasVolatileVariant(Instruction *I, unsigned AddrSpace) const;
/// Return true if target doesn't mind addresses in vectors.
bool prefersVectorizedAddressing() const;
/// Return the cost of the scaling factor used in the addressing
/// mode represented by AM for this target, for a load/store
/// of the specified type.
/// If the AM is supported, the return value must be >= 0.
/// If the AM is not supported, it returns a negative value.
/// TODO: Handle pre/postinc as well.
int getScalingFactorCost(Type *Ty, GlobalValue *BaseGV, int64_t BaseOffset,
bool HasBaseReg, int64_t Scale,
unsigned AddrSpace = 0) const;
/// Return true if the loop strength reduce pass should make
/// Instruction* based TTI queries to isLegalAddressingMode(). This is
/// needed on SystemZ, where e.g. a memcpy can only have a 12 bit unsigned
/// immediate offset and no index register.
bool LSRWithInstrQueries() const;
/// Return true if it's free to truncate a value of type Ty1 to type
/// Ty2. e.g. On x86 it's free to truncate a i32 value in register EAX to i16
/// by referencing its sub-register AX.
bool isTruncateFree(Type *Ty1, Type *Ty2) const;
/// Return true if it is profitable to hoist instruction in the
/// then/else to before if.
bool isProfitableToHoist(Instruction *I) const;
bool useAA() const;
/// Return true if this type is legal.
bool isTypeLegal(Type *Ty) const;
/// Returns the target's jmp_buf alignment in bytes.
unsigned getJumpBufAlignment() const;
/// Returns the target's jmp_buf size in bytes.
unsigned getJumpBufSize() const;
/// Return true if switches should be turned into lookup tables for the
/// target.
bool shouldBuildLookupTables() const;
/// Return true if switches should be turned into lookup tables
/// containing this constant value for the target.
bool shouldBuildLookupTablesForConstant(Constant *C) const;
/// Return true if the input function which is cold at all call sites,
/// should use coldcc calling convention.
bool useColdCCForColdCall(Function &F) const;
unsigned getScalarizationOverhead(Type *Ty, bool Insert, bool Extract) const;
unsigned getOperandsScalarizationOverhead(ArrayRef<const Value *> Args,
unsigned VF) const;
/// If target has efficient vector element load/store instructions, it can
/// return true here so that insertion/extraction costs are not added to
/// the scalarization cost of a load/store.
bool supportsEfficientVectorElementLoadStore() const;
/// Don't restrict interleaved unrolling to small loops.
bool enableAggressiveInterleaving(bool LoopHasReductions) const;
/// If not nullptr, enable inline expansion of memcmp. IsZeroCmp is
/// true if this is the expansion of memcmp(p1, p2, s) == 0.
struct MemCmpExpansionOptions {
// The list of available load sizes (in bytes), sorted in decreasing order.
SmallVector<unsigned, 8> LoadSizes;
};
const MemCmpExpansionOptions *enableMemCmpExpansion(bool IsZeroCmp) const;
/// Enable matching of interleaved access groups.
bool enableInterleavedAccessVectorization() const;
/// Enable matching of interleaved access groups that contain predicated
/// accesses or gaps and therefore vectorized using masked
/// vector loads/stores.
bool enableMaskedInterleavedAccessVectorization() const;
/// Indicate that it is potentially unsafe to automatically vectorize
/// floating-point operations because the semantics of vector and scalar
/// floating-point semantics may differ. For example, ARM NEON v7 SIMD math
/// does not support IEEE-754 denormal numbers, while depending on the
/// platform, scalar floating-point math does.
/// This applies to floating-point math operations and calls, not memory
/// operations, shuffles, or casts.
bool isFPVectorizationPotentiallyUnsafe() const;
/// Determine if the target supports unaligned memory accesses.
bool allowsMisalignedMemoryAccesses(LLVMContext &Context,
unsigned BitWidth, unsigned AddressSpace = 0,
unsigned Alignment = 1,
bool *Fast = nullptr) const;
/// Return hardware support for population count.
PopcntSupportKind getPopcntSupport(unsigned IntTyWidthInBit) const;
/// Return true if the hardware has a fast square-root instruction.
bool haveFastSqrt(Type *Ty) const;
/// Return true if it is faster to check if a floating-point value is NaN
/// (or not-NaN) versus a comparison against a constant FP zero value.
/// Targets should override this if materializing a 0.0 for comparison is
/// generally as cheap as checking for ordered/unordered.
bool isFCmpOrdCheaperThanFCmpZero(Type *Ty) const;
/// Return the expected cost of supporting the floating point operation
/// of the specified type.
int getFPOpCost(Type *Ty) const;
/// Return the expected cost of materializing for the given integer
/// immediate of the specified type.
int getIntImmCost(const APInt &Imm, Type *Ty) const;
/// Return the expected cost of materialization for the given integer
/// immediate of the specified type for a given instruction. The cost can be
/// zero if the immediate can be folded into the specified instruction.
int getIntImmCost(unsigned Opc, unsigned Idx, const APInt &Imm,
Type *Ty) const;
int getIntImmCost(Intrinsic::ID IID, unsigned Idx, const APInt &Imm,
Type *Ty) const;
/// Return the expected cost for the given integer when optimising
/// for size. This is different than the other integer immediate cost
/// functions in that it is subtarget agnostic. This is useful when you e.g.
/// target one ISA such as Aarch32 but smaller encodings could be possible
/// with another such as Thumb. This return value is used as a penalty when
/// the total costs for a constant is calculated (the bigger the cost, the
/// more beneficial constant hoisting is).
int getIntImmCodeSizeCost(unsigned Opc, unsigned Idx, const APInt &Imm,
Type *Ty) const;
/// @}
/// \name Vector Target Information
/// @{
/// The various kinds of shuffle patterns for vector queries.
enum ShuffleKind {
SK_Broadcast, ///< Broadcast element 0 to all other elements.
SK_Reverse, ///< Reverse the order of the vector.
SK_Select, ///< Selects elements from the corresponding lane of
///< either source operand. This is equivalent to a
///< vector select with a constant condition operand.
SK_Transpose, ///< Transpose two vectors.
SK_InsertSubvector, ///< InsertSubvector. Index indicates start offset.
SK_ExtractSubvector,///< ExtractSubvector Index indicates start offset.
SK_PermuteTwoSrc, ///< Merge elements from two source vectors into one
///< with any shuffle mask.
SK_PermuteSingleSrc ///< Shuffle elements of single source vector with any
///< shuffle mask.
};
/// Additional information about an operand's possible values.
enum OperandValueKind {
OK_AnyValue, // Operand can have any value.
OK_UniformValue, // Operand is uniform (splat of a value).
OK_UniformConstantValue, // Operand is uniform constant.
OK_NonUniformConstantValue // Operand is a non uniform constant value.
};
/// Additional properties of an operand's values.
enum OperandValueProperties { OP_None = 0, OP_PowerOf2 = 1 };
/// \return The number of scalar or vector registers that the target has.
/// If 'Vectors' is true, it returns the number of vector registers. If it is
/// set to false, it returns the number of scalar registers.
unsigned getNumberOfRegisters(bool Vector) const;
/// \return The width of the largest scalar or vector register type.
unsigned getRegisterBitWidth(bool Vector) const;
/// \return The width of the smallest vector register type.
unsigned getMinVectorRegisterBitWidth() const;
/// \return True if the vectorization factor should be chosen to
/// make the vector of the smallest element type match the size of a
/// vector register. For wider element types, this could result in
/// creating vectors that span multiple vector registers.
/// If false, the vectorization factor will be chosen based on the
/// size of the widest element type.
bool shouldMaximizeVectorBandwidth(bool OptSize) const;
/// \return The minimum vectorization factor for types of given element
/// bit width, or 0 if there is no mimimum VF. The returned value only
/// applies when shouldMaximizeVectorBandwidth returns true.
unsigned getMinimumVF(unsigned ElemWidth) const;
/// \return True if it should be considered for address type promotion.
/// \p AllowPromotionWithoutCommonHeader Set true if promoting \p I is
/// profitable without finding other extensions fed by the same input.
bool shouldConsiderAddressTypePromotion(
const Instruction &I, bool &AllowPromotionWithoutCommonHeader) const;
/// \return The size of a cache line in bytes.
unsigned getCacheLineSize() const;
/// The possible cache levels
enum class CacheLevel {
L1D, // The L1 data cache
L2D, // The L2 data cache
// We currently do not model L3 caches, as their sizes differ widely between
// microarchitectures. Also, we currently do not have a use for L3 cache
// size modeling yet.
};
/// \return The size of the cache level in bytes, if available.
llvm::Optional<unsigned> getCacheSize(CacheLevel Level) const;
/// \return The associativity of the cache level, if available.
llvm::Optional<unsigned> getCacheAssociativity(CacheLevel Level) const;
/// \return How much before a load we should place the prefetch instruction.
/// This is currently measured in number of instructions.
unsigned getPrefetchDistance() const;
/// \return Some HW prefetchers can handle accesses up to a certain constant
/// stride. This is the minimum stride in bytes where it makes sense to start
/// adding SW prefetches. The default is 1, i.e. prefetch with any stride.
unsigned getMinPrefetchStride() const;
/// \return The maximum number of iterations to prefetch ahead. If the
/// required number of iterations is more than this number, no prefetching is
/// performed.
unsigned getMaxPrefetchIterationsAhead() const;
/// \return The maximum interleave factor that any transform should try to
/// perform for this target. This number depends on the level of parallelism
/// and the number of execution units in the CPU.
unsigned getMaxInterleaveFactor(unsigned VF) const;
/// Collect properties of V used in cost analysis, e.g. OP_PowerOf2.
static OperandValueKind getOperandInfo(Value *V,
OperandValueProperties &OpProps);
/// This is an approximation of reciprocal throughput of a math/logic op.
/// A higher cost indicates less expected throughput.
/// From Agner Fog's guides, reciprocal throughput is "the average number of
/// clock cycles per instruction when the instructions are not part of a
/// limiting dependency chain."
/// Therefore, costs should be scaled to account for multiple execution units
/// on the target that can process this type of instruction. For example, if
/// there are 5 scalar integer units and 2 vector integer units that can
/// calculate an 'add' in a single cycle, this model should indicate that the
/// cost of the vector add instruction is 2.5 times the cost of the scalar
/// add instruction.
/// \p Args is an optional argument which holds the instruction operands
/// values so the TTI can analyze those values searching for special
/// cases or optimizations based on those values.
int getArithmeticInstrCost(
unsigned Opcode, Type *Ty, OperandValueKind Opd1Info = OK_AnyValue,
OperandValueKind Opd2Info = OK_AnyValue,
OperandValueProperties Opd1PropInfo = OP_None,
OperandValueProperties Opd2PropInfo = OP_None,
ArrayRef<const Value *> Args = ArrayRef<const Value *>()) const;
/// \return The cost of a shuffle instruction of kind Kind and of type Tp.
/// The index and subtype parameters are used by the subvector insertion and
/// extraction shuffle kinds to show the insert/extract point and the type of
/// the subvector being inserted/extracted.
/// NOTE: For subvector extractions Tp represents the source type.
int getShuffleCost(ShuffleKind Kind, Type *Tp, int Index = 0,
Type *SubTp = nullptr) const;
/// \return The expected cost of cast instructions, such as bitcast, trunc,
/// zext, etc. If there is an existing instruction that holds Opcode, it
/// may be passed in the 'I' parameter.
int getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src,
const Instruction *I = nullptr) const;
/// \return The expected cost of a sign- or zero-extended vector extract. Use
/// -1 to indicate that there is no information about the index value.
int getExtractWithExtendCost(unsigned Opcode, Type *Dst, VectorType *VecTy,
unsigned Index = -1) const;
/// \return The expected cost of control-flow related instructions such as
/// Phi, Ret, Br.
int getCFInstrCost(unsigned Opcode) const;
/// \returns The expected cost of compare and select instructions. If there
/// is an existing instruction that holds Opcode, it may be passed in the
/// 'I' parameter.
int getCmpSelInstrCost(unsigned Opcode, Type *ValTy,
Type *CondTy = nullptr, const Instruction *I = nullptr) const;
/// \return The expected cost of vector Insert and Extract.
/// Use -1 to indicate that there is no information on the index value.
int getVectorInstrCost(unsigned Opcode, Type *Val, unsigned Index = -1) const;
/// \return The cost of Load and Store instructions.
int getMemoryOpCost(unsigned Opcode, Type *Src, unsigned Alignment,
unsigned AddressSpace, const Instruction *I = nullptr) const;
/// \return The cost of masked Load and Store instructions.
int getMaskedMemoryOpCost(unsigned Opcode, Type *Src, unsigned Alignment,
unsigned AddressSpace) const;
/// \return The cost of Gather or Scatter operation
/// \p Opcode - is a type of memory access Load or Store
/// \p DataTy - a vector type of the data to be loaded or stored
/// \p Ptr - pointer [or vector of pointers] - address[es] in memory
/// \p VariableMask - true when the memory access is predicated with a mask
/// that is not a compile-time constant
/// \p Alignment - alignment of single element
int getGatherScatterOpCost(unsigned Opcode, Type *DataTy, Value *Ptr,
bool VariableMask, unsigned Alignment) const;
/// \return The cost of the interleaved memory operation.
/// \p Opcode is the memory operation code
/// \p VecTy is the vector type of the interleaved access.
/// \p Factor is the interleave factor
/// \p Indices is the indices for interleaved load members (as interleaved
/// load allows gaps)
/// \p Alignment is the alignment of the memory operation
/// \p AddressSpace is address space of the pointer.
/// \p UseMaskForCond indicates if the memory access is predicated.
/// \p UseMaskForGaps indicates if gaps should be masked.
int getInterleavedMemoryOpCost(unsigned Opcode, Type *VecTy, unsigned Factor,
ArrayRef<unsigned> Indices, unsigned Alignment,
unsigned AddressSpace,
bool UseMaskForCond = false,
bool UseMaskForGaps = false) const;
/// Calculate the cost of performing a vector reduction.
///
/// This is the cost of reducing the vector value of type \p Ty to a scalar
/// value using the operation denoted by \p Opcode. The form of the reduction
/// can either be a pairwise reduction or a reduction that splits the vector
/// at every reduction level.
///
/// Pairwise:
/// (v0, v1, v2, v3)
/// ((v0+v1), (v2+v3), undef, undef)
/// Split:
/// (v0, v1, v2, v3)
/// ((v0+v2), (v1+v3), undef, undef)
int getArithmeticReductionCost(unsigned Opcode, Type *Ty,
bool IsPairwiseForm) const;
int getMinMaxReductionCost(Type *Ty, Type *CondTy, bool IsPairwiseForm,
bool IsUnsigned) const;
/// \returns The cost of Intrinsic instructions. Analyses the real arguments.
/// Three cases are handled: 1. scalar instruction 2. vector instruction
/// 3. scalar instruction which is to be vectorized with VF.
int getIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy,
ArrayRef<Value *> Args, FastMathFlags FMF,
unsigned VF = 1) const;
/// \returns The cost of Intrinsic instructions. Types analysis only.
/// If ScalarizationCostPassed is UINT_MAX, the cost of scalarizing the
/// arguments and the return value will be computed based on types.
int getIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy,
ArrayRef<Type *> Tys, FastMathFlags FMF,
unsigned ScalarizationCostPassed = UINT_MAX) const;
/// \returns The cost of Call instructions.
int getCallInstrCost(Function *F, Type *RetTy, ArrayRef<Type *> Tys) const;
/// \returns The number of pieces into which the provided type must be
/// split during legalization. Zero is returned when the answer is unknown.
unsigned getNumberOfParts(Type *Tp) const;
/// \returns The cost of the address computation. For most targets this can be
/// merged into the instruction indexing mode. Some targets might want to
/// distinguish between address computation for memory operations on vector
/// types and scalar types. Such targets should override this function.
/// The 'SE' parameter holds pointer for the scalar evolution object which
/// is used in order to get the Ptr step value in case of constant stride.
/// The 'Ptr' parameter holds SCEV of the access pointer.
int getAddressComputationCost(Type *Ty, ScalarEvolution *SE = nullptr,
const SCEV *Ptr = nullptr) const;
/// \returns The cost, if any, of keeping values of the given types alive
/// over a callsite.
///
/// Some types may require the use of register classes that do not have
/// any callee-saved registers, so would require a spill and fill.
unsigned getCostOfKeepingLiveOverCall(ArrayRef<Type *> Tys) const;
/// \returns True if the intrinsic is a supported memory intrinsic. Info
/// will contain additional information - whether the intrinsic may write
/// or read to memory, volatility and the pointer. Info is undefined
/// if false is returned.
bool getTgtMemIntrinsic(IntrinsicInst *Inst, MemIntrinsicInfo &Info) const;
/// \returns The maximum element size, in bytes, for an element
/// unordered-atomic memory intrinsic.
unsigned getAtomicMemIntrinsicMaxElementSize() const;
/// \returns A value which is the result of the given memory intrinsic. New
/// instructions may be created to extract the result from the given intrinsic
/// memory operation. Returns nullptr if the target cannot create a result
/// from the given intrinsic.
Value *getOrCreateResultFromMemIntrinsic(IntrinsicInst *Inst,
Type *ExpectedType) const;
/// \returns The type to use in a loop expansion of a memcpy call.
Type *getMemcpyLoopLoweringType(LLVMContext &Context, Value *Length,
unsigned SrcAlign, unsigned DestAlign) const;
/// \param[out] OpsOut The operand types to copy RemainingBytes of memory.
/// \param RemainingBytes The number of bytes to copy.
///
/// Calculates the operand types to use when copying \p RemainingBytes of
/// memory, where source and destination alignments are \p SrcAlign and
/// \p DestAlign respectively.
void getMemcpyLoopResidualLoweringType(SmallVectorImpl<Type *> &OpsOut,
LLVMContext &Context,
unsigned RemainingBytes,
unsigned SrcAlign,
unsigned DestAlign) const;
/// \returns True if the two functions have compatible attributes for inlining
/// purposes.
bool areInlineCompatible(const Function *Caller,
const Function *Callee) const;
/// The type of load/store indexing.
enum MemIndexedMode {
MIM_Unindexed, ///< No indexing.
MIM_PreInc, ///< Pre-incrementing.
MIM_PreDec, ///< Pre-decrementing.
MIM_PostInc, ///< Post-incrementing.
MIM_PostDec ///< Post-decrementing.
};
/// \returns True if the specified indexed load for the given type is legal.
bool isIndexedLoadLegal(enum MemIndexedMode Mode, Type *Ty) const;
/// \returns True if the specified indexed store for the given type is legal.
bool isIndexedStoreLegal(enum MemIndexedMode Mode, Type *Ty) const;
/// \returns The bitwidth of the largest vector type that should be used to
/// load/store in the given address space.
unsigned getLoadStoreVecRegBitWidth(unsigned AddrSpace) const;
/// \returns True if the load instruction is legal to vectorize.
bool isLegalToVectorizeLoad(LoadInst *LI) const;
/// \returns True if the store instruction is legal to vectorize.
bool isLegalToVectorizeStore(StoreInst *SI) const;
/// \returns True if it is legal to vectorize the given load chain.
bool isLegalToVectorizeLoadChain(unsigned ChainSizeInBytes,
unsigned Alignment,
unsigned AddrSpace) const;
/// \returns True if it is legal to vectorize the given store chain.
bool isLegalToVectorizeStoreChain(unsigned ChainSizeInBytes,
unsigned Alignment,
unsigned AddrSpace) const;
/// \returns The new vector factor value if the target doesn't support \p
/// SizeInBytes loads or has a better vector factor.
unsigned getLoadVectorFactor(unsigned VF, unsigned LoadSize,
unsigned ChainSizeInBytes,
VectorType *VecTy) const;
/// \returns The new vector factor value if the target doesn't support \p
/// SizeInBytes stores or has a better vector factor.
unsigned getStoreVectorFactor(unsigned VF, unsigned StoreSize,
unsigned ChainSizeInBytes,
VectorType *VecTy) const;
/// Flags describing the kind of vector reduction.
struct ReductionFlags {
ReductionFlags() : IsMaxOp(false), IsSigned(false), NoNaN(false) {}
bool IsMaxOp; ///< If the op a min/max kind, true if it's a max operation.
bool IsSigned; ///< Whether the operation is a signed int reduction.
bool NoNaN; ///< If op is an fp min/max, whether NaNs may be present.
};
/// \returns True if the target wants to handle the given reduction idiom in
/// the intrinsics form instead of the shuffle form.
bool useReductionIntrinsic(unsigned Opcode, Type *Ty,
ReductionFlags Flags) const;
/// \returns True if the target wants to expand the given reduction intrinsic
/// into a shuffle sequence.
bool shouldExpandReduction(const IntrinsicInst *II) const;
/// @}
private:
/// Estimate the latency of specified instruction.
/// Returns 1 as the default value.
int getInstructionLatency(const Instruction *I) const;
/// Returns the expected throughput cost of the instruction.
/// Returns -1 if the cost is unknown.
int getInstructionThroughput(const Instruction *I) const;
/// The abstract base class used to type erase specific TTI
/// implementations.
class Concept;
/// The template model for the base class which wraps a concrete
/// implementation in a type erased interface.
template <typename T> class Model;
std::unique_ptr<Concept> TTIImpl;
};
class TargetTransformInfo::Concept {
public:
virtual ~Concept() = 0;
virtual const DataLayout &getDataLayout() const = 0;
virtual int getOperationCost(unsigned Opcode, Type *Ty, Type *OpTy) = 0;
virtual int getGEPCost(Type *PointeeType, const Value *Ptr,
ArrayRef<const Value *> Operands) = 0;
virtual int getExtCost(const Instruction *I, const Value *Src) = 0;
virtual int getCallCost(FunctionType *FTy, int NumArgs) = 0;
virtual int getCallCost(const Function *F, int NumArgs) = 0;
virtual int getCallCost(const Function *F,
ArrayRef<const Value *> Arguments) = 0;
virtual unsigned getInliningThresholdMultiplier() = 0;
virtual int getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
ArrayRef<Type *> ParamTys) = 0;
virtual int getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
ArrayRef<const Value *> Arguments) = 0;
virtual unsigned getEstimatedNumberOfCaseClusters(const SwitchInst &SI,
unsigned &JTSize) = 0;
virtual int
getUserCost(const User *U, ArrayRef<const Value *> Operands) = 0;
virtual bool hasBranchDivergence() = 0;
virtual bool isSourceOfDivergence(const Value *V) = 0;
virtual bool isAlwaysUniform(const Value *V) = 0;
virtual unsigned getFlatAddressSpace() = 0;
virtual bool isLoweredToCall(const Function *F) = 0;
virtual void getUnrollingPreferences(Loop *L, ScalarEvolution &,
UnrollingPreferences &UP) = 0;
virtual bool isLegalAddImmediate(int64_t Imm) = 0;
virtual bool isLegalICmpImmediate(int64_t Imm) = 0;
virtual bool isLegalAddressingMode(Type *Ty, GlobalValue *BaseGV,
int64_t BaseOffset, bool HasBaseReg,
int64_t Scale,
unsigned AddrSpace,
Instruction *I) = 0;
virtual bool isLSRCostLess(TargetTransformInfo::LSRCost &C1,
TargetTransformInfo::LSRCost &C2) = 0;
virtual bool canMacroFuseCmp() = 0;
virtual bool shouldFavorPostInc() const = 0;
virtual bool isLegalMaskedStore(Type *DataType) = 0;
virtual bool isLegalMaskedLoad(Type *DataType) = 0;
virtual bool isLegalMaskedScatter(Type *DataType) = 0;
virtual bool isLegalMaskedGather(Type *DataType) = 0;
virtual bool hasDivRemOp(Type *DataType, bool IsSigned) = 0;
virtual bool hasVolatileVariant(Instruction *I, unsigned AddrSpace) = 0;
virtual bool prefersVectorizedAddressing() = 0;
virtual int getScalingFactorCost(Type *Ty, GlobalValue *BaseGV,
int64_t BaseOffset, bool HasBaseReg,
int64_t Scale, unsigned AddrSpace) = 0;
virtual bool LSRWithInstrQueries() = 0;
virtual bool isTruncateFree(Type *Ty1, Type *Ty2) = 0;
virtual bool isProfitableToHoist(Instruction *I) = 0;
virtual bool useAA() = 0;
virtual bool isTypeLegal(Type *Ty) = 0;
virtual unsigned getJumpBufAlignment() = 0;
virtual unsigned getJumpBufSize() = 0;
virtual bool shouldBuildLookupTables() = 0;
virtual bool shouldBuildLookupTablesForConstant(Constant *C) = 0;
virtual bool useColdCCForColdCall(Function &F) = 0;
virtual unsigned
getScalarizationOverhead(Type *Ty, bool Insert, bool Extract) = 0;
virtual unsigned getOperandsScalarizationOverhead(ArrayRef<const Value *> Args,
unsigned VF) = 0;
virtual bool supportsEfficientVectorElementLoadStore() = 0;
virtual bool enableAggressiveInterleaving(bool LoopHasReductions) = 0;
virtual const MemCmpExpansionOptions *enableMemCmpExpansion(
bool IsZeroCmp) const = 0;
virtual bool enableInterleavedAccessVectorization() = 0;
virtual bool enableMaskedInterleavedAccessVectorization() = 0;
virtual bool isFPVectorizationPotentiallyUnsafe() = 0;
virtual bool allowsMisalignedMemoryAccesses(LLVMContext &Context,
unsigned BitWidth,
unsigned AddressSpace,
unsigned Alignment,
bool *Fast) = 0;
virtual PopcntSupportKind getPopcntSupport(unsigned IntTyWidthInBit) = 0;
virtual bool haveFastSqrt(Type *Ty) = 0;
virtual bool isFCmpOrdCheaperThanFCmpZero(Type *Ty) = 0;
virtual int getFPOpCost(Type *Ty) = 0;
virtual int getIntImmCodeSizeCost(unsigned Opc, unsigned Idx, const APInt &Imm,
Type *Ty) = 0;
virtual int getIntImmCost(const APInt &Imm, Type *Ty) = 0;
virtual int getIntImmCost(unsigned Opc, unsigned Idx, const APInt &Imm,
Type *Ty) = 0;
virtual int getIntImmCost(Intrinsic::ID IID, unsigned Idx, const APInt &Imm,
Type *Ty) = 0;
virtual unsigned getNumberOfRegisters(bool Vector) = 0;
virtual unsigned getRegisterBitWidth(bool Vector) const = 0;
virtual unsigned getMinVectorRegisterBitWidth() = 0;
virtual bool shouldMaximizeVectorBandwidth(bool OptSize) const = 0;
virtual unsigned getMinimumVF(unsigned ElemWidth) const = 0;
virtual bool shouldConsiderAddressTypePromotion(
const Instruction &I, bool &AllowPromotionWithoutCommonHeader) = 0;
virtual unsigned getCacheLineSize() = 0;
virtual llvm::Optional<unsigned> getCacheSize(CacheLevel Level) = 0;
virtual llvm::Optional<unsigned> getCacheAssociativity(CacheLevel Level) = 0;
virtual unsigned getPrefetchDistance() = 0;
virtual unsigned getMinPrefetchStride() = 0;
virtual unsigned getMaxPrefetchIterationsAhead() = 0;
virtual unsigned getMaxInterleaveFactor(unsigned VF) = 0;
virtual unsigned
getArithmeticInstrCost(unsigned Opcode, Type *Ty, OperandValueKind Opd1Info,
OperandValueKind Opd2Info,
OperandValueProperties Opd1PropInfo,
OperandValueProperties Opd2PropInfo,
ArrayRef<const Value *> Args) = 0;
virtual int getShuffleCost(ShuffleKind Kind, Type *Tp, int Index,
Type *SubTp) = 0;
virtual int getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src,
const Instruction *I) = 0;
virtual int getExtractWithExtendCost(unsigned Opcode, Type *Dst,
VectorType *VecTy, unsigned Index) = 0;
virtual int getCFInstrCost(unsigned Opcode) = 0;
virtual int getCmpSelInstrCost(unsigned Opcode, Type *ValTy,
Type *CondTy, const Instruction *I) = 0;
virtual int getVectorInstrCost(unsigned Opcode, Type *Val,
unsigned Index) = 0;
virtual int getMemoryOpCost(unsigned Opcode, Type *Src, unsigned Alignment,
unsigned AddressSpace, const Instruction *I) = 0;
virtual int getMaskedMemoryOpCost(unsigned Opcode, Type *Src,
unsigned Alignment,
unsigned AddressSpace) = 0;
virtual int getGatherScatterOpCost(unsigned Opcode, Type *DataTy,
Value *Ptr, bool VariableMask,
unsigned Alignment) = 0;
virtual int getInterleavedMemoryOpCost(unsigned Opcode, Type *VecTy,
unsigned Factor,
ArrayRef<unsigned> Indices,
unsigned Alignment,
unsigned AddressSpace,
bool UseMaskForCond = false,
bool UseMaskForGaps = false) = 0;
virtual int getArithmeticReductionCost(unsigned Opcode, Type *Ty,
bool IsPairwiseForm) = 0;
virtual int getMinMaxReductionCost(Type *Ty, Type *CondTy,
bool IsPairwiseForm, bool IsUnsigned) = 0;
virtual int getIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy,
ArrayRef<Type *> Tys, FastMathFlags FMF,
unsigned ScalarizationCostPassed) = 0;
virtual int getIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy,
ArrayRef<Value *> Args, FastMathFlags FMF, unsigned VF) = 0;
virtual int getCallInstrCost(Function *F, Type *RetTy,
ArrayRef<Type *> Tys) = 0;
virtual unsigned getNumberOfParts(Type *Tp) = 0;
virtual int getAddressComputationCost(Type *Ty, ScalarEvolution *SE,
const SCEV *Ptr) = 0;
virtual unsigned getCostOfKeepingLiveOverCall(ArrayRef<Type *> Tys) = 0;
virtual bool getTgtMemIntrinsic(IntrinsicInst *Inst,
MemIntrinsicInfo &Info) = 0;
virtual unsigned getAtomicMemIntrinsicMaxElementSize() const = 0;
virtual Value *getOrCreateResultFromMemIntrinsic(IntrinsicInst *Inst,
Type *ExpectedType) = 0;
virtual Type *getMemcpyLoopLoweringType(LLVMContext &Context, Value *Length,
unsigned SrcAlign,
unsigned DestAlign) const = 0;
virtual void getMemcpyLoopResidualLoweringType(
SmallVectorImpl<Type *> &OpsOut, LLVMContext &Context,
unsigned RemainingBytes, unsigned SrcAlign, unsigned DestAlign) const = 0;
virtual bool areInlineCompatible(const Function *Caller,
const Function *Callee) const = 0;
virtual bool isIndexedLoadLegal(MemIndexedMode Mode, Type *Ty) const = 0;
virtual bool isIndexedStoreLegal(MemIndexedMode Mode,Type *Ty) const = 0;
virtual unsigned getLoadStoreVecRegBitWidth(unsigned AddrSpace) const = 0;
virtual bool isLegalToVectorizeLoad(LoadInst *LI) const = 0;
virtual bool isLegalToVectorizeStore(StoreInst *SI) const = 0;
virtual bool isLegalToVectorizeLoadChain(unsigned ChainSizeInBytes,
unsigned Alignment,
unsigned AddrSpace) const = 0;
virtual bool isLegalToVectorizeStoreChain(unsigned ChainSizeInBytes,
unsigned Alignment,
unsigned AddrSpace) const = 0;
virtual unsigned getLoadVectorFactor(unsigned VF, unsigned LoadSize,
unsigned ChainSizeInBytes,
VectorType *VecTy) const = 0;
virtual unsigned getStoreVectorFactor(unsigned VF, unsigned StoreSize,
unsigned ChainSizeInBytes,
VectorType *VecTy) const = 0;
virtual bool useReductionIntrinsic(unsigned Opcode, Type *Ty,
ReductionFlags) const = 0;
virtual bool shouldExpandReduction(const IntrinsicInst *II) const = 0;
virtual int getInstructionLatency(const Instruction *I) = 0;
};
template <typename T>
class TargetTransformInfo::Model final : public TargetTransformInfo::Concept {
T Impl;
public:
Model(T Impl) : Impl(std::move(Impl)) {}
~Model() override {}
const DataLayout &getDataLayout() const override {
return Impl.getDataLayout();
}
int getOperationCost(unsigned Opcode, Type *Ty, Type *OpTy) override {
return Impl.getOperationCost(Opcode, Ty, OpTy);
}
int getGEPCost(Type *PointeeType, const Value *Ptr,
ArrayRef<const Value *> Operands) override {
return Impl.getGEPCost(PointeeType, Ptr, Operands);
}
int getExtCost(const Instruction *I, const Value *Src) override {
return Impl.getExtCost(I, Src);
}
int getCallCost(FunctionType *FTy, int NumArgs) override {
return Impl.getCallCost(FTy, NumArgs);
}
int getCallCost(const Function *F, int NumArgs) override {
return Impl.getCallCost(F, NumArgs);
}
int getCallCost(const Function *F,
ArrayRef<const Value *> Arguments) override {
return Impl.getCallCost(F, Arguments);
}
unsigned getInliningThresholdMultiplier() override {
return Impl.getInliningThresholdMultiplier();
}
int getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
ArrayRef<Type *> ParamTys) override {
return Impl.getIntrinsicCost(IID, RetTy, ParamTys);
}
int getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
ArrayRef<const Value *> Arguments) override {
return Impl.getIntrinsicCost(IID, RetTy, Arguments);
}
int getUserCost(const User *U, ArrayRef<const Value *> Operands) override {
return Impl.getUserCost(U, Operands);
}
bool hasBranchDivergence() override { return Impl.hasBranchDivergence(); }
bool isSourceOfDivergence(const Value *V) override {
return Impl.isSourceOfDivergence(V);
}
bool isAlwaysUniform(const Value *V) override {
return Impl.isAlwaysUniform(V);
}
unsigned getFlatAddressSpace() override {
return Impl.getFlatAddressSpace();
}
bool isLoweredToCall(const Function *F) override {
return Impl.isLoweredToCall(F);
}
void getUnrollingPreferences(Loop *L, ScalarEvolution &SE,
UnrollingPreferences &UP) override {
return Impl.getUnrollingPreferences(L, SE, UP);
}
bool isLegalAddImmediate(int64_t Imm) override {
return Impl.isLegalAddImmediate(Imm);
}
bool isLegalICmpImmediate(int64_t Imm) override {
return Impl.isLegalICmpImmediate(Imm);
}
bool isLegalAddressingMode(Type *Ty, GlobalValue *BaseGV, int64_t BaseOffset,
bool HasBaseReg, int64_t Scale,
unsigned AddrSpace,
Instruction *I) override {
return Impl.isLegalAddressingMode(Ty, BaseGV, BaseOffset, HasBaseReg,
Scale, AddrSpace, I);
}
bool isLSRCostLess(TargetTransformInfo::LSRCost &C1,
TargetTransformInfo::LSRCost &C2) override {
return Impl.isLSRCostLess(C1, C2);
}
bool canMacroFuseCmp() override {
return Impl.canMacroFuseCmp();
}
bool shouldFavorPostInc() const override {
return Impl.shouldFavorPostInc();
}
bool isLegalMaskedStore(Type *DataType) override {
return Impl.isLegalMaskedStore(DataType);
}
bool isLegalMaskedLoad(Type *DataType) override {
return Impl.isLegalMaskedLoad(DataType);
}
bool isLegalMaskedScatter(Type *DataType) override {
return Impl.isLegalMaskedScatter(DataType);
}
bool isLegalMaskedGather(Type *DataType) override {
return Impl.isLegalMaskedGather(DataType);
}
bool hasDivRemOp(Type *DataType, bool IsSigned) override {
return Impl.hasDivRemOp(DataType, IsSigned);
}
bool hasVolatileVariant(Instruction *I, unsigned AddrSpace) override {
return Impl.hasVolatileVariant(I, AddrSpace);
}
bool prefersVectorizedAddressing() override {
return Impl.prefersVectorizedAddressing();
}
int getScalingFactorCost(Type *Ty, GlobalValue *BaseGV, int64_t BaseOffset,
bool HasBaseReg, int64_t Scale,
unsigned AddrSpace) override {
return Impl.getScalingFactorCost(Ty, BaseGV, BaseOffset, HasBaseReg,
Scale, AddrSpace);
}
bool LSRWithInstrQueries() override {
return Impl.LSRWithInstrQueries();
}
bool isTruncateFree(Type *Ty1, Type *Ty2) override {
return Impl.isTruncateFree(Ty1, Ty2);
}
bool isProfitableToHoist(Instruction *I) override {
return Impl.isProfitableToHoist(I);
}
bool useAA() override { return Impl.useAA(); }
bool isTypeLegal(Type *Ty) override { return Impl.isTypeLegal(Ty); }
unsigned getJumpBufAlignment() override { return Impl.getJumpBufAlignment(); }
unsigned getJumpBufSize() override { return Impl.getJumpBufSize(); }
bool shouldBuildLookupTables() override {
return Impl.shouldBuildLookupTables();
}
bool shouldBuildLookupTablesForConstant(Constant *C) override {
return Impl.shouldBuildLookupTablesForConstant(C);
}
bool useColdCCForColdCall(Function &F) override {
return Impl.useColdCCForColdCall(F);
}
unsigned getScalarizationOverhead(Type *Ty, bool Insert,
bool Extract) override {
return Impl.getScalarizationOverhead(Ty, Insert, Extract);
}
unsigned getOperandsScalarizationOverhead(ArrayRef<const Value *> Args,
unsigned VF) override {
return Impl.getOperandsScalarizationOverhead(Args, VF);
}
bool supportsEfficientVectorElementLoadStore() override {
return Impl.supportsEfficientVectorElementLoadStore();
}
bool enableAggressiveInterleaving(bool LoopHasReductions) override {
return Impl.enableAggressiveInterleaving(LoopHasReductions);
}
const MemCmpExpansionOptions *enableMemCmpExpansion(
bool IsZeroCmp) const override {
return Impl.enableMemCmpExpansion(IsZeroCmp);
}
bool enableInterleavedAccessVectorization() override {
return Impl.enableInterleavedAccessVectorization();
}
bool enableMaskedInterleavedAccessVectorization() override {
return Impl.enableMaskedInterleavedAccessVectorization();
}
bool isFPVectorizationPotentiallyUnsafe() override {
return Impl.isFPVectorizationPotentiallyUnsafe();
}
bool allowsMisalignedMemoryAccesses(LLVMContext &Context,
unsigned BitWidth, unsigned AddressSpace,
unsigned Alignment, bool *Fast) override {
return Impl.allowsMisalignedMemoryAccesses(Context, BitWidth, AddressSpace,
Alignment, Fast);
}
PopcntSupportKind getPopcntSupport(unsigned IntTyWidthInBit) override {
return Impl.getPopcntSupport(IntTyWidthInBit);
}
bool haveFastSqrt(Type *Ty) override { return Impl.haveFastSqrt(Ty); }
bool isFCmpOrdCheaperThanFCmpZero(Type *Ty) override {
return Impl.isFCmpOrdCheaperThanFCmpZero(Ty);
}
int getFPOpCost(Type *Ty) override { return Impl.getFPOpCost(Ty); }
int getIntImmCodeSizeCost(unsigned Opc, unsigned Idx, const APInt &Imm,
Type *Ty) override {
return Impl.getIntImmCodeSizeCost(Opc, Idx, Imm, Ty);
}
int getIntImmCost(const APInt &Imm, Type *Ty) override {
return Impl.getIntImmCost(Imm, Ty);
}
int getIntImmCost(unsigned Opc, unsigned Idx, const APInt &Imm,
Type *Ty) override {
return Impl.getIntImmCost(Opc, Idx, Imm, Ty);
}
int getIntImmCost(Intrinsic::ID IID, unsigned Idx, const APInt &Imm,
Type *Ty) override {
return Impl.getIntImmCost(IID, Idx, Imm, Ty);
}
unsigned getNumberOfRegisters(bool Vector) override {
return Impl.getNumberOfRegisters(Vector);
}
unsigned getRegisterBitWidth(bool Vector) const override {
return Impl.getRegisterBitWidth(Vector);
}
unsigned getMinVectorRegisterBitWidth() override {
return Impl.getMinVectorRegisterBitWidth();
}
bool shouldMaximizeVectorBandwidth(bool OptSize) const override {
return Impl.shouldMaximizeVectorBandwidth(OptSize);
}
unsigned getMinimumVF(unsigned ElemWidth) const override {
return Impl.getMinimumVF(ElemWidth);
}
bool shouldConsiderAddressTypePromotion(
const Instruction &I, bool &AllowPromotionWithoutCommonHeader) override {
return Impl.shouldConsiderAddressTypePromotion(
I, AllowPromotionWithoutCommonHeader);
}
unsigned getCacheLineSize() override {
return Impl.getCacheLineSize();
}
llvm::Optional<unsigned> getCacheSize(CacheLevel Level) override {
return Impl.getCacheSize(Level);
}
llvm::Optional<unsigned> getCacheAssociativity(CacheLevel Level) override {
return Impl.getCacheAssociativity(Level);
}
unsigned getPrefetchDistance() override { return Impl.getPrefetchDistance(); }
unsigned getMinPrefetchStride() override {
return Impl.getMinPrefetchStride();
}
unsigned getMaxPrefetchIterationsAhead() override {
return Impl.getMaxPrefetchIterationsAhead();
}
unsigned getMaxInterleaveFactor(unsigned VF) override {
return Impl.getMaxInterleaveFactor(VF);
}
unsigned getEstimatedNumberOfCaseClusters(const SwitchInst &SI,
unsigned &JTSize) override {
return Impl.getEstimatedNumberOfCaseClusters(SI, JTSize);
}
unsigned
getArithmeticInstrCost(unsigned Opcode, Type *Ty, OperandValueKind Opd1Info,
OperandValueKind Opd2Info,
OperandValueProperties Opd1PropInfo,
OperandValueProperties Opd2PropInfo,
ArrayRef<const Value *> Args) override {
return Impl.getArithmeticInstrCost(Opcode, Ty, Opd1Info, Opd2Info,
Opd1PropInfo, Opd2PropInfo, Args);
}
int getShuffleCost(ShuffleKind Kind, Type *Tp, int Index,
Type *SubTp) override {
return Impl.getShuffleCost(Kind, Tp, Index, SubTp);
}
int getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src,
const Instruction *I) override {
return Impl.getCastInstrCost(Opcode, Dst, Src, I);
}
int getExtractWithExtendCost(unsigned Opcode, Type *Dst, VectorType *VecTy,
unsigned Index) override {
return Impl.getExtractWithExtendCost(Opcode, Dst, VecTy, Index);
}
int getCFInstrCost(unsigned Opcode) override {
return Impl.getCFInstrCost(Opcode);
}
int getCmpSelInstrCost(unsigned Opcode, Type *ValTy, Type *CondTy,
const Instruction *I) override {
return Impl.getCmpSelInstrCost(Opcode, ValTy, CondTy, I);
}
int getVectorInstrCost(unsigned Opcode, Type *Val, unsigned Index) override {
return Impl.getVectorInstrCost(Opcode, Val, Index);
}
int getMemoryOpCost(unsigned Opcode, Type *Src, unsigned Alignment,
unsigned AddressSpace, const Instruction *I) override {
return Impl.getMemoryOpCost(Opcode, Src, Alignment, AddressSpace, I);
}
int getMaskedMemoryOpCost(unsigned Opcode, Type *Src, unsigned Alignment,
unsigned AddressSpace) override {
return Impl.getMaskedMemoryOpCost(Opcode, Src, Alignment, AddressSpace);
}
int getGatherScatterOpCost(unsigned Opcode, Type *DataTy,
Value *Ptr, bool VariableMask,
unsigned Alignment) override {
return Impl.getGatherScatterOpCost(Opcode, DataTy, Ptr, VariableMask,
Alignment);
}
int getInterleavedMemoryOpCost(unsigned Opcode, Type *VecTy, unsigned Factor,
ArrayRef<unsigned> Indices, unsigned Alignment,
unsigned AddressSpace, bool UseMaskForCond,
bool UseMaskForGaps) override {
return Impl.getInterleavedMemoryOpCost(Opcode, VecTy, Factor, Indices,
Alignment, AddressSpace,
UseMaskForCond, UseMaskForGaps);
}
int getArithmeticReductionCost(unsigned Opcode, Type *Ty,
bool IsPairwiseForm) override {
return Impl.getArithmeticReductionCost(Opcode, Ty, IsPairwiseForm);
}
int getMinMaxReductionCost(Type *Ty, Type *CondTy,
bool IsPairwiseForm, bool IsUnsigned) override {
return Impl.getMinMaxReductionCost(Ty, CondTy, IsPairwiseForm, IsUnsigned);
}
int getIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy, ArrayRef<Type *> Tys,
FastMathFlags FMF, unsigned ScalarizationCostPassed) override {
return Impl.getIntrinsicInstrCost(ID, RetTy, Tys, FMF,
ScalarizationCostPassed);
}
int getIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy,
ArrayRef<Value *> Args, FastMathFlags FMF, unsigned VF) override {
return Impl.getIntrinsicInstrCost(ID, RetTy, Args, FMF, VF);
}
int getCallInstrCost(Function *F, Type *RetTy,
ArrayRef<Type *> Tys) override {
return Impl.getCallInstrCost(F, RetTy, Tys);
}
unsigned getNumberOfParts(Type *Tp) override {
return Impl.getNumberOfParts(Tp);
}
int getAddressComputationCost(Type *Ty, ScalarEvolution *SE,
const SCEV *Ptr) override {
return Impl.getAddressComputationCost(Ty, SE, Ptr);
}
unsigned getCostOfKeepingLiveOverCall(ArrayRef<Type *> Tys) override {
return Impl.getCostOfKeepingLiveOverCall(Tys);
}
bool getTgtMemIntrinsic(IntrinsicInst *Inst,
MemIntrinsicInfo &Info) override {
return Impl.getTgtMemIntrinsic(Inst, Info);
}
unsigned getAtomicMemIntrinsicMaxElementSize() const override {
return Impl.getAtomicMemIntrinsicMaxElementSize();
}
Value *getOrCreateResultFromMemIntrinsic(IntrinsicInst *Inst,
Type *ExpectedType) override {
return Impl.getOrCreateResultFromMemIntrinsic(Inst, ExpectedType);
}
Type *getMemcpyLoopLoweringType(LLVMContext &Context, Value *Length,
unsigned SrcAlign,
unsigned DestAlign) const override {
return Impl.getMemcpyLoopLoweringType(Context, Length, SrcAlign, DestAlign);
}
void getMemcpyLoopResidualLoweringType(SmallVectorImpl<Type *> &OpsOut,
LLVMContext &Context,
unsigned RemainingBytes,
unsigned SrcAlign,
unsigned DestAlign) const override {
Impl.getMemcpyLoopResidualLoweringType(OpsOut, Context, RemainingBytes,
SrcAlign, DestAlign);
}
bool areInlineCompatible(const Function *Caller,
const Function *Callee) const override {
return Impl.areInlineCompatible(Caller, Callee);
}
bool isIndexedLoadLegal(MemIndexedMode Mode, Type *Ty) const override {
return Impl.isIndexedLoadLegal(Mode, Ty, getDataLayout());
}
bool isIndexedStoreLegal(MemIndexedMode Mode, Type *Ty) const override {
return Impl.isIndexedStoreLegal(Mode, Ty, getDataLayout());
}
unsigned getLoadStoreVecRegBitWidth(unsigned AddrSpace) const override {
return Impl.getLoadStoreVecRegBitWidth(AddrSpace);
}
bool isLegalToVectorizeLoad(LoadInst *LI) const override {
return Impl.isLegalToVectorizeLoad(LI);
}
bool isLegalToVectorizeStore(StoreInst *SI) const override {
return Impl.isLegalToVectorizeStore(SI);
}
bool isLegalToVectorizeLoadChain(unsigned ChainSizeInBytes,
unsigned Alignment,
unsigned AddrSpace) const override {
return Impl.isLegalToVectorizeLoadChain(ChainSizeInBytes, Alignment,
AddrSpace);
}
bool isLegalToVectorizeStoreChain(unsigned ChainSizeInBytes,
unsigned Alignment,
unsigned AddrSpace) const override {
return Impl.isLegalToVectorizeStoreChain(ChainSizeInBytes, Alignment,
AddrSpace);
}
unsigned getLoadVectorFactor(unsigned VF, unsigned LoadSize,
unsigned ChainSizeInBytes,
VectorType *VecTy) const override {
return Impl.getLoadVectorFactor(VF, LoadSize, ChainSizeInBytes, VecTy);
}
unsigned getStoreVectorFactor(unsigned VF, unsigned StoreSize,
unsigned ChainSizeInBytes,
VectorType *VecTy) const override {
return Impl.getStoreVectorFactor(VF, StoreSize, ChainSizeInBytes, VecTy);
}
bool useReductionIntrinsic(unsigned Opcode, Type *Ty,
ReductionFlags Flags) const override {
return Impl.useReductionIntrinsic(Opcode, Ty, Flags);
}
bool shouldExpandReduction(const IntrinsicInst *II) const override {
return Impl.shouldExpandReduction(II);
}
int getInstructionLatency(const Instruction *I) override {
return Impl.getInstructionLatency(I);
}
};
template <typename T>
TargetTransformInfo::TargetTransformInfo(T Impl)
: TTIImpl(new Model<T>(Impl)) {}
/// Analysis pass providing the \c TargetTransformInfo.
///
/// The core idea of the TargetIRAnalysis is to expose an interface through
/// which LLVM targets can analyze and provide information about the middle
/// end's target-independent IR. This supports use cases such as target-aware
/// cost modeling of IR constructs.
///
/// This is a function analysis because much of the cost modeling for targets
/// is done in a subtarget specific way and LLVM supports compiling different
/// functions targeting different subtargets in order to support runtime
/// dispatch according to the observed subtarget.
class TargetIRAnalysis : public AnalysisInfoMixin<TargetIRAnalysis> {
public:
typedef TargetTransformInfo Result;
/// Default construct a target IR analysis.
///
/// This will use the module's datalayout to construct a baseline
/// conservative TTI result.
TargetIRAnalysis();
/// Construct an IR analysis pass around a target-provide callback.
///
/// The callback will be called with a particular function for which the TTI
/// is needed and must return a TTI object for that function.
TargetIRAnalysis(std::function<Result(const Function &)> TTICallback);
// Value semantics. We spell out the constructors for MSVC.
TargetIRAnalysis(const TargetIRAnalysis &Arg)
: TTICallback(Arg.TTICallback) {}
TargetIRAnalysis(TargetIRAnalysis &&Arg)
: TTICallback(std::move(Arg.TTICallback)) {}
TargetIRAnalysis &operator=(const TargetIRAnalysis &RHS) {
TTICallback = RHS.TTICallback;
return *this;
}
TargetIRAnalysis &operator=(TargetIRAnalysis &&RHS) {
TTICallback = std::move(RHS.TTICallback);
return *this;
}
Result run(const Function &F, FunctionAnalysisManager &);
private:
friend AnalysisInfoMixin<TargetIRAnalysis>;
static AnalysisKey Key;
/// The callback used to produce a result.
///
/// We use a completely opaque callback so that targets can provide whatever
/// mechanism they desire for constructing the TTI for a given function.
///
/// FIXME: Should we really use std::function? It's relatively inefficient.
/// It might be possible to arrange for even stateful callbacks to outlive
/// the analysis and thus use a function_ref which would be lighter weight.
/// This may also be less error prone as the callback is likely to reference
/// the external TargetMachine, and that reference needs to never dangle.
std::function<Result(const Function &)> TTICallback;
/// Helper function used as the callback in the default constructor.
static Result getDefaultTTI(const Function &F);
};
/// Wrapper pass for TargetTransformInfo.
///
/// This pass can be constructed from a TTI object which it stores internally
/// and is queried by passes.
class TargetTransformInfoWrapperPass : public ImmutablePass {
TargetIRAnalysis TIRA;
Optional<TargetTransformInfo> TTI;
virtual void anchor();
public:
static char ID;
/// We must provide a default constructor for the pass but it should
/// never be used.
///
/// Use the constructor below or call one of the creation routines.
TargetTransformInfoWrapperPass();
explicit TargetTransformInfoWrapperPass(TargetIRAnalysis TIRA);
TargetTransformInfo &getTTI(const Function &F);
};
/// Create an analysis pass wrapper around a TTI object.
///
/// This analysis pass just holds the TTI instance and makes it available to
/// clients.
ImmutablePass *createTargetTransformInfoWrapperPass(TargetIRAnalysis TIRA);
} // End llvm namespace
#endif