LLVM 20.0.0git
|
#include "llvm/CodeGen/CodeGenPrepare.h"
#include "llvm/ADT/APInt.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/BlockFrequencyInfo.h"
#include "llvm/Analysis/BranchProbabilityInfo.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/ProfileSummaryInfo.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Analysis/VectorUtils.h"
#include "llvm/CodeGen/Analysis.h"
#include "llvm/CodeGen/BasicBlockSectionsProfileReader.h"
#include "llvm/CodeGen/ISDOpcodes.h"
#include "llvm/CodeGen/SelectionDAGNodes.h"
#include "llvm/CodeGen/TargetLowering.h"
#include "llvm/CodeGen/TargetPassConfig.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/CodeGenTypes/MachineValueType.h"
#include "llvm/Config/llvm-config.h"
#include "llvm/IR/Argument.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/IntrinsicsAArch64.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/IR/ProfDataUtils.h"
#include "llvm/IR/Statepoint.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/Use.h"
#include "llvm/IR/User.h"
#include "llvm/IR/Value.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/IR/ValueMap.h"
#include "llvm/InitializePasses.h"
#include "llvm/Pass.h"
#include "llvm/Support/BlockFrequency.h"
#include "llvm/Support/BranchProbability.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/BypassSlowDivision.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/SimplifyLibCalls.h"
#include "llvm/Transforms/Utils/SizeOpts.h"
#include <algorithm>
#include <cassert>
#include <cstdint>
#include <iterator>
#include <limits>
#include <memory>
#include <optional>
#include <utility>
#include <vector>
Go to the source code of this file.
Macros | |
#define | DEBUG_TYPE "codegenprepare" |
Functions | |
STATISTIC (NumBlocksElim, "Number of blocks eliminated") | |
STATISTIC (NumPHIsElim, "Number of trivial PHIs eliminated") | |
STATISTIC (NumGEPsElim, "Number of GEPs converted to casts") | |
STATISTIC (NumCmpUses, "Number of uses of Cmp expressions replaced with uses of " "sunken Cmps") | |
STATISTIC (NumCastUses, "Number of uses of Cast expressions replaced with uses " "of sunken Casts") | |
STATISTIC (NumMemoryInsts, "Number of memory instructions whose address " "computations were sunk") | |
STATISTIC (NumMemoryInstsPhiCreated, "Number of phis created when address " "computations were sunk to memory instructions") | |
STATISTIC (NumMemoryInstsSelectCreated, "Number of select created when address " "computations were sunk to memory instructions") | |
STATISTIC (NumExtsMoved, "Number of [s|z]ext instructions combined with loads") | |
STATISTIC (NumExtUses, "Number of uses of [s|z]ext instructions optimized") | |
STATISTIC (NumAndsAdded, "Number of and mask instructions added to form ext loads") | |
STATISTIC (NumAndUses, "Number of uses of and mask instructions optimized") | |
STATISTIC (NumRetsDup, "Number of return instructions duplicated") | |
STATISTIC (NumDbgValueMoved, "Number of debug value instructions moved") | |
STATISTIC (NumSelectsExpanded, "Number of selects turned into branches") | |
STATISTIC (NumStoreExtractExposed, "Number of store(extractelement) exposed") | |
INITIALIZE_PASS_BEGIN (CodeGenPrepareLegacyPass, DEBUG_TYPE, "Optimize for code generation", false, false) INITIALIZE_PASS_END(CodeGenPrepareLegacyPass | |
static void | replaceAllUsesWith (Value *Old, Value *New, SmallSet< BasicBlock *, 32 > &FreshBBs, bool IsHuge) |
Replace all old uses with new ones, and push the updated BBs into FreshBBs. | |
static void | computeBaseDerivedRelocateMap (const SmallVectorImpl< GCRelocateInst * > &AllRelocateCalls, MapVector< GCRelocateInst *, SmallVector< GCRelocateInst *, 0 > > &RelocateInstMap) |
static bool | getGEPSmallConstantIntOffsetV (GetElementPtrInst *GEP, SmallVectorImpl< Value * > &OffsetV) |
static bool | simplifyRelocatesOffABase (GCRelocateInst *RelocatedBase, const SmallVectorImpl< GCRelocateInst * > &Targets) |
static bool | SinkCast (CastInst *CI) |
Sink the specified cast instruction into its user blocks. | |
static bool | OptimizeNoopCopyExpression (CastInst *CI, const TargetLowering &TLI, const DataLayout &DL) |
If the specified cast instruction is a noop copy (e.g. | |
static bool | matchIncrement (const Instruction *IVInc, Instruction *&LHS, Constant *&Step) |
static std::optional< std::pair< Instruction *, Constant * > > | getIVIncrement (const PHINode *PN, const LoopInfo *LI) |
If given PN is an inductive variable with value IVInc coming from the backedge, and on each iteration it gets increased by Step, return pair <IVInc, Step>. | |
static bool | isIVIncrement (const Value *V, const LoopInfo *LI) |
static bool | matchUAddWithOverflowConstantEdgeCases (CmpInst *Cmp, BinaryOperator *&Add) |
Match special-case patterns that check for unsigned add overflow. | |
static bool | sinkCmpExpression (CmpInst *Cmp, const TargetLowering &TLI) |
Sink the given CmpInst into user blocks to reduce the number of virtual registers that must be created and coalesced. | |
static bool | foldICmpWithDominatingICmp (CmpInst *Cmp, const TargetLowering &TLI) |
For pattern like: | |
static bool | swapICmpOperandsToExposeCSEOpportunities (CmpInst *Cmp) |
Many architectures use the same instruction for both subtract and cmp. | |
static bool | foldFCmpToFPClassTest (CmpInst *Cmp, const TargetLowering &TLI, const DataLayout &DL) |
static bool | isRemOfLoopIncrementWithLoopInvariant (Instruction *Rem, const LoopInfo *LI, Value *&RemAmtOut, PHINode *&LoopIncrPNOut) |
static bool | foldURemOfLoopIncrement (Instruction *Rem, const DataLayout *DL, const LoopInfo *LI, SmallSet< BasicBlock *, 32 > &FreshBBs, bool IsHuge) |
static bool | sinkAndCmp0Expression (Instruction *AndI, const TargetLowering &TLI, SetOfInstrs &InsertedInsts) |
Duplicate and sink the given 'and' instruction into user blocks where it is used in a compare to allow isel to generate better code for targets where this operation can be combined. | |
static bool | isExtractBitsCandidateUse (Instruction *User) |
Check if the candidates could be combined with a shift instruction, which includes: | |
static bool | SinkShiftAndTruncate (BinaryOperator *ShiftI, Instruction *User, ConstantInt *CI, DenseMap< BasicBlock *, BinaryOperator * > &InsertedShifts, const TargetLowering &TLI, const DataLayout &DL) |
Sink both shift and truncate instruction to the use of truncate's BB. | |
static bool | OptimizeExtractBits (BinaryOperator *ShiftI, ConstantInt *CI, const TargetLowering &TLI, const DataLayout &DL) |
Sink the shift right instruction into user blocks if the uses could potentially be combined with this shift instruction and generate BitExtract instruction. | |
static bool | despeculateCountZeros (IntrinsicInst *CountZeros, LoopInfo &LI, const TargetLowering *TLI, const DataLayout *DL, ModifyDT &ModifiedDT, SmallSet< BasicBlock *, 32 > &FreshBBs, bool IsHugeFunc) |
If counting leading or trailing zeros is an expensive operation and a zero input is defined, add a check for zero to avoid calling the intrinsic. | |
static bool | isIntrinsicOrLFToBeTailCalled (const TargetLibraryInfo *TLInfo, const CallInst *CI) |
static bool | MightBeFoldableInst (Instruction *I) |
This is a little filter, which returns true if an addressing computation involving I might be folded into a load/store accessing it. | |
static bool | isPromotedInstructionLegal (const TargetLowering &TLI, const DataLayout &DL, Value *Val) |
Check whether or not Val is a legal instruction for TLI . | |
static bool | IsOperandAMemoryOperand (CallInst *CI, InlineAsm *IA, Value *OpVal, const TargetLowering &TLI, const TargetRegisterInfo &TRI) |
Check to see if all uses of OpVal by the specified inline asm call are due to memory operands. | |
static bool | FindAllMemoryUses (Instruction *I, SmallVectorImpl< std::pair< Use *, Type * > > &MemoryUses, SmallPtrSetImpl< Instruction * > &ConsideredInsts, const TargetLowering &TLI, const TargetRegisterInfo &TRI, bool OptSize, ProfileSummaryInfo *PSI, BlockFrequencyInfo *BFI, unsigned &SeenInsts) |
Recursively walk all the uses of I until we find a memory use. | |
static bool | FindAllMemoryUses (Instruction *I, SmallVectorImpl< std::pair< Use *, Type * > > &MemoryUses, const TargetLowering &TLI, const TargetRegisterInfo &TRI, bool OptSize, ProfileSummaryInfo *PSI, BlockFrequencyInfo *BFI) |
static bool | IsNonLocalValue (Value *V, BasicBlock *BB) |
Return true if the specified values are defined in a different basic block than BB. | |
static bool | hasSameExtUse (Value *Val, const TargetLowering &TLI) |
Check if all the uses of Val are equivalent (or free) zero or sign extensions. | |
static bool | sinkSelectOperand (const TargetTransformInfo *TTI, Value *V) |
Check if V (an operand of a select instruction) is an expensive instruction that is only used once. | |
static bool | isFormingBranchFromSelectProfitable (const TargetTransformInfo *TTI, const TargetLowering *TLI, SelectInst *SI) |
Returns true if a SelectInst should be turned into an explicit branch. | |
static Value * | getTrueOrFalseValue (SelectInst *SI, bool isTrue, const SmallPtrSet< const Instruction *, 2 > &Selects) |
If isTrue is true, return the true value of SI , otherwise return false value of SI . | |
static bool | splitMergedValStore (StoreInst &SI, const DataLayout &DL, const TargetLowering &TLI) |
For the instruction sequence of store below, F and I values are bundled together as an i64 value before being stored into memory. | |
static bool | GEPSequentialConstIndexed (GetElementPtrInst *GEP) |
static bool | tryUnmergingGEPsAcrossIndirectBr (GetElementPtrInst *GEPI, const TargetTransformInfo *TTI) |
static bool | optimizeBranch (BranchInst *Branch, const TargetLowering &TLI, SmallSet< BasicBlock *, 32 > &FreshBBs, bool IsHugeFunc) |
static void | DbgInserterHelper (DbgValueInst *DVI, Instruction *VI) |
static void | DbgInserterHelper (DbgVariableRecord *DVR, Instruction *VI) |
static void | scaleWeights (uint64_t &NewTrue, uint64_t &NewFalse) |
Scale down both weights to fit into uint32_t. | |
Variables | |
static cl::opt< bool > | DisableBranchOpts ("disable-cgp-branch-opts", cl::Hidden, cl::init(false), cl::desc("Disable branch optimizations in CodeGenPrepare")) |
static cl::opt< bool > | DisableGCOpts ("disable-cgp-gc-opts", cl::Hidden, cl::init(false), cl::desc("Disable GC optimizations in CodeGenPrepare")) |
static cl::opt< bool > | DisableSelectToBranch ("disable-cgp-select2branch", cl::Hidden, cl::init(false), cl::desc("Disable select to branch conversion.")) |
static cl::opt< bool > | AddrSinkUsingGEPs ("addr-sink-using-gep", cl::Hidden, cl::init(true), cl::desc("Address sinking in CGP using GEPs.")) |
static cl::opt< bool > | EnableAndCmpSinking ("enable-andcmp-sinking", cl::Hidden, cl::init(true), cl::desc("Enable sinkinig and/cmp into branches.")) |
static cl::opt< bool > | DisableStoreExtract ("disable-cgp-store-extract", cl::Hidden, cl::init(false), cl::desc("Disable store(extract) optimizations in CodeGenPrepare")) |
static cl::opt< bool > | StressStoreExtract ("stress-cgp-store-extract", cl::Hidden, cl::init(false), cl::desc("Stress test store(extract) optimizations in CodeGenPrepare")) |
static cl::opt< bool > | DisableExtLdPromotion ("disable-cgp-ext-ld-promotion", cl::Hidden, cl::init(false), cl::desc("Disable ext(promotable(ld)) -> promoted(ext(ld)) optimization in " "CodeGenPrepare")) |
static cl::opt< bool > | StressExtLdPromotion ("stress-cgp-ext-ld-promotion", cl::Hidden, cl::init(false), cl::desc("Stress test ext(promotable(ld)) -> promoted(ext(ld)) " "optimization in CodeGenPrepare")) |
static cl::opt< bool > | DisablePreheaderProtect ("disable-preheader-prot", cl::Hidden, cl::init(false), cl::desc("Disable protection against removing loop preheaders")) |
static cl::opt< bool > | ProfileGuidedSectionPrefix ("profile-guided-section-prefix", cl::Hidden, cl::init(true), cl::desc("Use profile info to add section prefix for hot/cold functions")) |
static cl::opt< bool > | ProfileUnknownInSpecialSection ("profile-unknown-in-special-section", cl::Hidden, cl::desc("In profiling mode like sampleFDO, if a function doesn't have " "profile, we cannot tell the function is cold for sure because " "it may be a function newly added without ever being sampled. " "With the flag enabled, compiler can put such profile unknown " "functions into a special section, so runtime system can choose " "to handle it in a different way than .text section, to save " "RAM for example. ")) |
static cl::opt< bool > | BBSectionsGuidedSectionPrefix ("bbsections-guided-section-prefix", cl::Hidden, cl::init(true), cl::desc("Use the basic-block-sections profile to determine the text " "section prefix for hot functions. Functions with " "basic-block-sections profile will be placed in `.text.hot` " "regardless of their FDO profile info. Other functions won't be " "impacted, i.e., their prefixes will be decided by FDO/sampleFDO " "profiles.")) |
static cl::opt< uint64_t > | FreqRatioToSkipMerge ("cgp-freq-ratio-to-skip-merge", cl::Hidden, cl::init(2), cl::desc("Skip merging empty blocks if (frequency of empty block) / " "(frequency of destination block) is greater than this ratio")) |
static cl::opt< bool > | ForceSplitStore ("force-split-store", cl::Hidden, cl::init(false), cl::desc("Force store splitting no matter what the target query says.")) |
static cl::opt< bool > | EnableTypePromotionMerge ("cgp-type-promotion-merge", cl::Hidden, cl::desc("Enable merging of redundant sexts when one is dominating" " the other."), cl::init(true)) |
static cl::opt< bool > | DisableComplexAddrModes ("disable-complex-addr-modes", cl::Hidden, cl::init(false), cl::desc("Disables combining addressing modes with different parts " "in optimizeMemoryInst.")) |
static cl::opt< bool > | AddrSinkNewPhis ("addr-sink-new-phis", cl::Hidden, cl::init(false), cl::desc("Allow creation of Phis in Address sinking.")) |
static cl::opt< bool > | AddrSinkNewSelects ("addr-sink-new-select", cl::Hidden, cl::init(true), cl::desc("Allow creation of selects in Address sinking.")) |
static cl::opt< bool > | AddrSinkCombineBaseReg ("addr-sink-combine-base-reg", cl::Hidden, cl::init(true), cl::desc("Allow combining of BaseReg field in Address sinking.")) |
static cl::opt< bool > | AddrSinkCombineBaseGV ("addr-sink-combine-base-gv", cl::Hidden, cl::init(true), cl::desc("Allow combining of BaseGV field in Address sinking.")) |
static cl::opt< bool > | AddrSinkCombineBaseOffs ("addr-sink-combine-base-offs", cl::Hidden, cl::init(true), cl::desc("Allow combining of BaseOffs field in Address sinking.")) |
static cl::opt< bool > | AddrSinkCombineScaledReg ("addr-sink-combine-scaled-reg", cl::Hidden, cl::init(true), cl::desc("Allow combining of ScaledReg field in Address sinking.")) |
static cl::opt< bool > | EnableGEPOffsetSplit ("cgp-split-large-offset-gep", cl::Hidden, cl::init(true), cl::desc("Enable splitting large offset of GEP.")) |
static cl::opt< bool > | EnableICMP_EQToICMP_ST ("cgp-icmp-eq2icmp-st", cl::Hidden, cl::init(false), cl::desc("Enable ICMP_EQ to ICMP_S(L|G)T conversion.")) |
static cl::opt< bool > | VerifyBFIUpdates ("cgp-verify-bfi-updates", cl::Hidden, cl::init(false), cl::desc("Enable BFI update verification for " "CodeGenPrepare.")) |
static cl::opt< bool > | OptimizePhiTypes ("cgp-optimize-phi-types", cl::Hidden, cl::init(true), cl::desc("Enable converting phi types in CodeGenPrepare")) |
static cl::opt< unsigned > | HugeFuncThresholdInCGPP ("cgpp-huge-func", cl::init(10000), cl::Hidden, cl::desc("Least BB number of huge function.")) |
static cl::opt< unsigned > | MaxAddressUsersToScan ("cgp-max-address-users-to-scan", cl::init(100), cl::Hidden, cl::desc("Max number of address users to look at")) |
static cl::opt< bool > | DisableDeletePHIs ("disable-cgp-delete-phis", cl::Hidden, cl::init(false), cl::desc("Disable elimination of dead PHI nodes.")) |
DEBUG_TYPE | |
Optimize for code | generation |
Optimize for code | false |
#define DEBUG_TYPE "codegenprepare" |
Definition at line 110 of file CodeGenPrepare.cpp.
|
static |
Definition at line 1197 of file CodeGenPrepare.cpp.
References llvm::MapVector< KeyT, ValueT, MapType, VectorType >::end(), llvm::MapVector< KeyT, ValueT, MapType, VectorType >::find(), I, and llvm::MapVector< KeyT, ValueT, MapType, VectorType >::insert().
|
static |
Definition at line 8732 of file CodeGenPrepare.cpp.
References llvm::Instruction::insertAfter(), llvm::Instruction::insertBefore(), and llvm::Instruction::removeFromParent().
|
static |
Definition at line 8740 of file CodeGenPrepare.cpp.
References llvm::BasicBlock::getFirstInsertionPt(), llvm::BasicBlock::insertDbgRecordAfter(), llvm::BasicBlock::insertDbgRecordBefore(), and llvm::DbgRecord::removeFromParent().
|
static |
If counting leading or trailing zeros is an expensive operation and a zero input is defined, add a check for zero to avoid calling the intrinsic.
We want to transform: z = call i64 @llvm.cttz.i64(i64 A, i1 false)
into: entry: cmpz = icmp eq i64 A, 0 br i1 cmpz, label cond.end, label cond.false cond.false: z = call i64 @llvm.cttz.i64(i64 A, i1 true) br label cond.end cond.end: ctz = phi i64 [ 64, entry ], [ z, cond.false ]
If the transform is performed, return true and set ModifiedDT to true.
Definition at line 2422 of file CodeGenPrepare.cpp.
References llvm::PHINode::addIncoming(), llvm::BasicBlock::begin(), llvm::BitWidth, llvm::IRBuilderBase::CreateCondBr(), llvm::IRBuilderBase::CreateFreeze(), llvm::IRBuilderBase::CreateICmpEQ(), llvm::IRBuilderBase::CreatePHI(), DL, llvm::Instruction::eraseFromParent(), llvm::Value::getContext(), llvm::Instruction::getDebugLoc(), llvm::IRBuilderBase::getInt(), llvm::IntrinsicInst::getIntrinsicID(), llvm::LoopInfoBase< BlockT, LoopT >::getLoopFor(), llvm::Constant::getNullValue(), llvm::User::getOperand(), llvm::User::getOperandUse(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::Type::getScalarSizeInBits(), llvm::BasicBlock::getTerminator(), llvm::IRBuilderBase::getTrue(), llvm::Value::getType(), llvm::SmallSet< T, N, C >::insert(), llvm::TargetLoweringBase::isCheapToSpeculateCtlz(), llvm::TargetLoweringBase::isCheapToSpeculateCttz(), llvm::isGuaranteedNotToBeUndefOrPoison(), llvm::isKnownNonZero(), llvm::Type::isVectorTy(), llvm::PatternMatch::m_One(), llvm::PatternMatch::match(), replaceAllUsesWith(), llvm::CallBase::setArgOperand(), llvm::IRBuilderBase::SetCurrentDebugLocation(), llvm::IRBuilderBase::SetInsertPoint(), and llvm::BasicBlock::splitBasicBlock().
|
static |
Definition at line 5414 of file CodeGenPrepare.cpp.
References FindAllMemoryUses(), I, and TRI.
|
static |
Recursively walk all the uses of I until we find a memory use.
If we find an obviously non-foldable instruction, return true. Add accessed addresses and types to MemoryUses.
Definition at line 5339 of file CodeGenPrepare.cpp.
References FindAllMemoryUses(), llvm::StoreInst::getPointerOperandIndex(), llvm::AtomicCmpXchgInst::getPointerOperandIndex(), llvm::AtomicRMWInst::getPointerOperandIndex(), getType(), I, llvm::SmallPtrSetImpl< PtrType >::insert(), IsOperandAMemoryOperand(), MaxAddressUsersToScan, MightBeFoldableInst(), llvm::shouldOptimizeForSize(), and TRI.
Referenced by FindAllMemoryUses().
|
static |
Definition at line 1946 of file CodeGenPrepare.cpp.
References llvm::IRBuilderBase::createIsFPClass(), DL, llvm::fcInf, llvm::fcmpToClassTest(), llvm::fcNan, llvm::getFCmpCondCode(), llvm::User::getOperand(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::CmpInst::getPredicate(), llvm::EVT::getSimpleVT(), llvm::TargetLoweringBase::getValueType(), llvm::TargetLoweringBase::isCondCodeLegal(), llvm::TargetLoweringBase::isFAbsFree(), and llvm::RecursivelyDeleteTriviallyDeadInstructions().
|
static |
For pattern like:
DomCond = icmp sgt/slt CmpOp0, CmpOp1 (might not be in DomBB) ... DomBB: ... br DomCond, TrueBB, CmpBB CmpBB: (with DomBB being the single predecessor) ... Cmp = icmp eq CmpOp0, CmpOp1 ...
It would use two comparison on targets that lowering of icmp sgt/slt is different from lowering of icmp eq (PowerPC). This function try to convert 'Cmp = icmp eq CmpOp0, CmpOp1' to ' Cmp = icmp slt/sgt CmpOp0, CmpOp1'. After that, DomCond and Cmp can use the same comparison so reduce one comparison.
Return true if any changes are made.
Definition at line 1847 of file CodeGenPrepare.cpp.
References assert(), EnableICMP_EQToICMP_ST, llvm::BasicBlock::getSinglePredecessor(), llvm::CmpInst::getSwappedPredicate(), llvm::BasicBlock::getTerminator(), llvm::CmpInst::ICMP_EQ, llvm::CmpInst::ICMP_SGT, llvm::CmpInst::ICMP_SLT, llvm::BranchInst::isConditional(), llvm::TargetLoweringBase::isEqualityCmpFoldedWithSignedCmp(), llvm_unreachable, llvm::PatternMatch::m_Br(), llvm::PatternMatch::m_ICmp(), llvm::PatternMatch::m_Specific(), llvm::PatternMatch::m_Value(), llvm::PatternMatch::match(), and llvm::BranchInst::swapSuccessors().
|
static |
Definition at line 2045 of file CodeGenPrepare.cpp.
References llvm::PHINode::addIncoming(), llvm::IRBuilderBase::CreateICmp(), llvm::IRBuilderBase::CreateNUWAdd(), llvm::IRBuilderBase::CreatePHI(), llvm::IRBuilderBase::CreateSelect(), DL, llvm::Instruction::eraseFromParent(), llvm::Value::getContext(), llvm::PHINode::getIncomingValueForBlock(), llvm::LoopInfoBase< BlockT, LoopT >::getLoopFor(), llvm::Constant::getNullValue(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::Value::getType(), llvm::CmpInst::ICMP_EQ, llvm::SmallSet< T, N, C >::insert(), isRemOfLoopIncrementWithLoopInvariant(), llvm::PatternMatch::m_ImmConstant(), llvm::PatternMatch::match(), replaceAllUsesWith(), llvm::IRBuilderBase::SetInsertPoint(), and llvm::simplifyURemInst().
|
static |
Definition at line 8192 of file CodeGenPrepare.cpp.
References GEP, llvm::gep_type_begin(), and I.
Referenced by tryUnmergingGEPsAcrossIndirectBr().
|
static |
Definition at line 1232 of file CodeGenPrepare.cpp.
References GEP, and llvm::SmallVectorTemplateBase< T, bool >::push_back().
Referenced by simplifyRelocatesOffABase().
|
static |
If given PN
is an inductive variable with value IVInc coming from the backedge, and on each iteration it gets increased by Step, return pair <IVInc, Step>.
Otherwise, return std::nullopt.
Definition at line 1523 of file CodeGenPrepare.cpp.
References llvm::PHINode::getIncomingValueForBlock(), llvm::LoopInfoBase< BlockT, LoopT >::getLoopFor(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), LHS, and matchIncrement().
Referenced by isIVIncrement(), and isRemOfLoopIncrementWithLoopInvariant().
|
static |
If isTrue
is true, return the true value of SI
, otherwise return false value of SI
.
If the true/false value of SI
is defined by any select instructions in Selects
, look through the defining select instruction until the true/false value is not defined in Selects
.
Definition at line 7158 of file CodeGenPrepare.cpp.
References assert(), and llvm::SmallPtrSetImpl< PtrType >::count().
|
static |
Check if all the uses of Val
are equivalent (or free) zero or sign extensions.
Definition at line 6162 of file CodeGenPrepare.cpp.
References assert(), llvm::Type::getIntegerBitWidth(), llvm::Type::getScalarType(), llvm::Value::getType(), llvm::TargetLoweringBase::isZExtFree(), llvm::Value::use_empty(), llvm::Value::user_begin(), and llvm::Value::users().
INITIALIZE_PASS_BEGIN | ( | CodeGenPrepareLegacyPass | , |
DEBUG_TYPE | , | ||
"Optimize for code generation" | , | ||
false | , | ||
false | |||
) |
|
static |
Check if the candidates could be combined with a shift instruction, which includes:
Definition at line 2211 of file CodeGenPrepare.cpp.
References llvm::User::getOperand().
Referenced by OptimizeExtractBits().
|
static |
Returns true if a SelectInst should be turned into an explicit branch.
Definition at line 7113 of file CodeGenPrepare.cpp.
References llvm::extractBranchWeights(), llvm::BranchProbability::getBranchProbability(), llvm::TargetTransformInfo::getPredictableBranchThreshold(), llvm::TargetLoweringBase::isPredictableSelectExpensive(), and sinkSelectOperand().
|
static |
Definition at line 2692 of file CodeGenPrepare.cpp.
References assert(), llvm::CallBase::getCalledFunction(), llvm::TargetLibraryInfo::getLibFunc(), II, and llvm::Value::use_empty().
Definition at line 1538 of file CodeGenPrepare.cpp.
References getIVIncrement(), I, LHS, and matchIncrement().
|
static |
Return true if the specified values are defined in a different basic block than BB.
Definition at line 5560 of file CodeGenPrepare.cpp.
References I.
|
static |
Check to see if all uses of OpVal by the specified inline asm call are due to memory operands.
If so, return true, otherwise return false.
Definition at line 5314 of file CodeGenPrepare.cpp.
References llvm::TargetLowering::C_Memory, llvm::TargetLowering::ComputeConstraintToUse(), F, llvm::Instruction::getFunction(), llvm::TargetLowering::ParseConstraints(), and TRI.
Referenced by FindAllMemoryUses().
|
static |
Check whether or not Val
is a legal instruction for TLI
.
Val
is assumed to be the product of some type promotion. Therefore if Val
has an undefined state in TLI
, this is assumed to be legal, as the non-promoted value would have had the same state. Definition at line 4488 of file CodeGenPrepare.cpp.
References DL, llvm::Instruction::getOpcode(), llvm::Value::getType(), llvm::TargetLoweringBase::getValueType(), llvm::TargetLoweringBase::InstructionOpcodeToISD(), and llvm::TargetLoweringBase::isOperationLegalOrCustom().
|
static |
Definition at line 1979 of file CodeGenPrepare.cpp.
References getIVIncrement(), llvm::LoopInfoBase< BlockT, LoopT >::getLoopFor(), llvm::PatternMatch::m_c_NUWAdd(), llvm::PatternMatch::m_One(), llvm::PatternMatch::m_Specific(), llvm::PatternMatch::m_URem(), llvm::PatternMatch::m_Value(), and llvm::PatternMatch::match().
Referenced by foldURemOfLoopIncrement().
|
static |
Definition at line 1504 of file CodeGenPrepare.cpp.
References llvm::ConstantExpr::getNeg(), LHS, llvm::PatternMatch::m_Add(), llvm::PatternMatch::m_Constant(), llvm::PatternMatch::m_Instruction(), llvm::PatternMatch::m_Sub(), and llvm::PatternMatch::match().
Referenced by getIVIncrement(), and isIVIncrement().
|
static |
Match special-case patterns that check for unsigned add overflow.
Definition at line 1634 of file CodeGenPrepare.cpp.
References A, llvm::Add, B, llvm::Constant::getAllOnesValue(), llvm::CmpInst::ICMP_EQ, llvm::CmpInst::ICMP_NE, llvm::PatternMatch::m_Add(), llvm::PatternMatch::m_AllOnes(), llvm::PatternMatch::m_Specific(), llvm::PatternMatch::m_ZeroInt(), and llvm::PatternMatch::match().
|
static |
This is a little filter, which returns true if an addressing computation involving I might be folded into a load/store accessing it.
This doesn't need to be perfect, but needs to accept at least the set of instructions that MatchOperationAddr can.
Definition at line 4457 of file CodeGenPrepare.cpp.
References I.
Referenced by FindAllMemoryUses().
|
static |
Definition at line 8360 of file CodeGenPrepare.cpp.
References llvm::IRBuilderBase::CreateCmp(), llvm::dbgs(), llvm::Instruction::dropPoisonGeneratingFlags(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::Value::getType(), llvm::APInt::isPowerOf2(), LLVM_DEBUG, llvm::APInt::logBase2(), llvm::PatternMatch::m_Add(), llvm::PatternMatch::m_Shr(), llvm::PatternMatch::m_Specific(), llvm::PatternMatch::m_SpecificInt(), llvm::PatternMatch::m_Sub(), llvm::PatternMatch::match(), llvm::Instruction::moveBefore(), llvm::TargetLoweringBase::preferZeroCompareBranch(), replaceAllUsesWith(), and X.
|
static |
Sink the shift right instruction into user blocks if the uses could potentially be combined with this shift instruction and generate BitExtract instruction.
It will only be applied if the architecture supports BitExtract instruction. Here is an example: BB1: x.extract.shift = lshr i64 arg1, 32 BB2: x.extract.trunc = trunc i64 x.extract.shift to i16 ==>
BB2: x.extract.shift.1 = lshr i64 arg1, 32 x.extract.trunc = trunc i64 x.extract.shift.1 to i16
CodeGen will recognize the pattern in BB2 and generate BitExtract instruction. Return true if any changes are made.
Only insert instructions in each block once.
Definition at line 2320 of file CodeGenPrepare.cpp.
References assert(), DL, llvm::BasicBlock::end(), llvm::Instruction::eraseFromParent(), llvm::Instruction::getDebugLoc(), llvm::BasicBlock::getFirstInsertionPt(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::Value::getType(), llvm::TargetLoweringBase::getValueType(), llvm::Instruction::insertBefore(), isExtractBitsCandidateUse(), llvm::TargetLoweringBase::isTypeLegal(), llvm::salvageDebugInfo(), llvm::Instruction::setDebugLoc(), SinkShiftAndTruncate(), llvm::Value::use_empty(), llvm::Value::user_begin(), and llvm::Value::user_end().
|
static |
If the specified cast instruction is a noop copy (e.g.
it's casting from one pointer type to another, i32->i8 on PPC), sink it into user blocks to reduce the number of virtual registers that must be created and coalesced.
Return true if any changes are made.
Definition at line 1461 of file CodeGenPrepare.cpp.
References llvm::EVT::bitsLT(), DL, llvm::Value::getContext(), llvm::User::getOperand(), llvm::Value::getType(), llvm::TargetLoweringBase::getTypeAction(), llvm::TargetLoweringBase::getTypeToTransformTo(), llvm::TargetLoweringBase::getValueType(), llvm::TargetLoweringBase::isFreeAddrSpaceCast(), llvm::EVT::isInteger(), SinkCast(), and llvm::TargetLoweringBase::TypePromoteInteger.
|
static |
Replace all old uses with new ones, and push the updated BBs into FreshBBs.
Definition at line 1114 of file CodeGenPrepare.cpp.
References llvm::SmallSet< T, N, C >::insert(), llvm::Value::replaceAllUsesWith(), and llvm::Value::user_begin().
Referenced by despeculateCountZeros(), foldURemOfLoopIncrement(), llvm::AArch64TargetLowering::lowerDeinterleaveIntrinsicToLoad(), and optimizeBranch().
Scale down both weights to fit into uint32_t.
Definition at line 8848 of file CodeGenPrepare.cpp.
|
static |
Definition at line 1249 of file CodeGenPrepare.cpp.
References assert(), llvm::sampleprof::Base, llvm::IRBuilderBase::CreateBitCast(), llvm::IRBuilderBase::CreateGEP(), llvm::GCRelocateInst::getBasePtrIndex(), getGEPSmallConstantIntOffsetV(), llvm::ilist_node_with_parent< NodeTy, ParentTy, Options >::getNextNode(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::GCProjectionInst::getStatepoint(), llvm::Value::getType(), llvm::Instruction::moveBefore(), llvm::Value::replaceAllUsesWith(), llvm::IRBuilderBase::SetCurrentDebugLocation(), and llvm::Value::takeName().
|
static |
Duplicate and sink the given 'and' instruction into user blocks where it is used in a compare to allow isel to generate better code for targets where this operation can be combined.
Return true if any changes are made.
Definition at line 2135 of file CodeGenPrepare.cpp.
References assert(), llvm::BinaryOperator::Create(), llvm::dbgs(), llvm::Value::dump(), llvm::Instruction::eraseFromParent(), llvm::Instruction::getDebugLoc(), llvm::ilist_node_impl< OptionsT >::getIterator(), llvm::User::getOperand(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::Value::hasOneUse(), llvm::TargetLoweringBase::isMaskAndCmp0FoldingBeneficial(), llvm::APInt::isZero(), LLVM_DEBUG, llvm::Instruction::setDebugLoc(), llvm::Value::user_begin(), llvm::Value::user_end(), and llvm::Value::users().
Sink the specified cast instruction into its user blocks.
InsertedCasts - Only insert a cast in each block once.
Definition at line 1393 of file CodeGenPrepare.cpp.
References assert(), llvm::Instruction::clone(), llvm::BasicBlock::end(), llvm::Instruction::eraseFromParent(), llvm::BasicBlock::getFirstInsertionPt(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::BasicBlock::getTerminator(), llvm::Instruction::insertBefore(), llvm::Instruction::isEHPad(), llvm::salvageDebugInfo(), llvm::Value::use_empty(), llvm::Value::user_begin(), and llvm::Value::user_end().
Referenced by OptimizeNoopCopyExpression().
|
static |
Sink the given CmpInst into user blocks to reduce the number of virtual registers that must be created and coalesced.
This is a clear win except on targets with multiple condition code registers (PowerPC), where it might lose; some adjustment may be wanted there.
Return true if any changes are made.
Definition at line 1768 of file CodeGenPrepare.cpp.
References assert(), llvm::CmpInst::Create(), llvm::BasicBlock::end(), llvm::BasicBlock::getFirstInsertionPt(), llvm::TargetLoweringBase::hasMultipleConditionRegisters(), llvm::Instruction::insertBefore(), llvm::Instruction::setDebugLoc(), and llvm::TargetLoweringBase::useSoftFloat().
|
static |
Check if V (an operand of a select instruction) is an expensive instruction that is only used once.
Definition at line 7104 of file CodeGenPrepare.cpp.
References I, llvm::TargetTransformInfo::isExpensiveToSpeculativelyExecute(), and llvm::isSafeToSpeculativelyExecute().
Referenced by isFormingBranchFromSelectProfitable().
|
static |
Sink both shift and truncate instruction to the use of truncate's BB.
Definition at line 2227 of file CodeGenPrepare.cpp.
References assert(), llvm::CastInst::Create(), DL, llvm::BasicBlock::end(), llvm::Instruction::getDebugLoc(), llvm::BasicBlock::getFirstInsertionPt(), llvm::BinaryOperator::getOpcode(), llvm::Instruction::getOpcode(), llvm::User::getOperand(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::Value::getType(), llvm::TargetLoweringBase::getValueType(), llvm::Instruction::insertBefore(), llvm::TargetLoweringBase::InstructionOpcodeToISD(), llvm::TargetLoweringBase::isOperationLegalOrCustom(), and llvm::Instruction::setDebugLoc().
Referenced by OptimizeExtractBits().
|
static |
For the instruction sequence of store below, F and I values are bundled together as an i64 value before being stored into memory.
Sometimes it is more efficient to generate separate stores for F and I, which can remove the bitwise instructions or sink them to colder places.
(store (or (zext (bitcast F to i32) to i64), (shl (zext I to i64), 32)), addr) --> (store F, addr) and (store I, addr+4)
Similarly, splitting for other merged store can also be beneficial, like: For pair of {i32, i32}, i64 store --> two i32 stores. For pair of {i32, i16}, i64 store --> two i32 stores. For pair of {i16, i16}, i32 store --> two i16 stores. For pair of {i16, i8}, i32 store --> two i16 stores. For pair of {i8, i8}, i16 store --> two i8 stores.
We allow each target to determine specifically which kind of splitting is supported.
The store patterns are commonly seen from the simple code snippet below if only std::make_pair(...) is sroa transformed before inlined into hoo. void goo(const std::pair<int, float> &); hoo() { ... goo(std::make_pair(tmp, ftmp)); ... }
Although we already have similar splitting in DAG Combine, we duplicate it in CodeGenPrepare to catch the case in which pattern is across multiple BBs. The logic in DAG Combine is kept to catch case generated during code expansion.
Definition at line 8094 of file CodeGenPrepare.cpp.
References Addr, llvm::commonAlignment(), llvm::IRBuilderBase::CreateAlignedStore(), llvm::IRBuilderBase::CreateBitCast(), llvm::IRBuilderBase::CreateGEP(), llvm::IRBuilderBase::CreateZExtOrBitCast(), DL, ForceSplitStore, llvm::EVT::getEVT(), llvm::Type::getInt32Ty(), llvm::Type::getIntNTy(), llvm::Value::getType(), llvm::Type::isIntegerTy(), llvm::TargetLoweringBase::isMultiStoresCheaperThanBitsMerge(), llvm::Type::isScalableTy(), LValue, llvm::PatternMatch::m_c_Or(), llvm::PatternMatch::m_OneUse(), llvm::PatternMatch::m_Shl(), llvm::PatternMatch::m_SpecificInt(), llvm::PatternMatch::m_Value(), llvm::PatternMatch::m_ZExt(), llvm::PatternMatch::match(), llvm::IRBuilderBase::SetInsertPoint(), and llvm::Upper.
STATISTIC | ( | NumAndsAdded | , |
"Number of and mask instructions added to form ext loads" | |||
) |
STATISTIC | ( | NumAndUses | , |
"Number of uses of and mask instructions optimized" | |||
) |
STATISTIC | ( | NumBlocksElim | , |
"Number of blocks eliminated" | |||
) |
STATISTIC | ( | NumCastUses | , |
"Number of uses of Cast expressions replaced with uses " "of sunken Casts" | |||
) |
STATISTIC | ( | NumDbgValueMoved | , |
"Number of debug value instructions moved" | |||
) |
STATISTIC | ( | NumExtsMoved | , |
"Number of ext instructions combined with loads" | [s|z] | ||
) |
STATISTIC | ( | NumExtUses | , |
"Number of uses of ext instructions optimized" | [s|z] | ||
) |
STATISTIC | ( | NumGEPsElim | , |
"Number of GEPs converted to casts" | |||
) |
STATISTIC | ( | NumMemoryInsts | , |
"Number of memory instructions whose address " "computations were sunk" | |||
) |
STATISTIC | ( | NumMemoryInstsPhiCreated | , |
"Number of phis created when address " "computations were sunk to memory instructions" | |||
) |
STATISTIC | ( | NumMemoryInstsSelectCreated | , |
"Number of select created when address " "computations were sunk to memory instructions" | |||
) |
STATISTIC | ( | NumPHIsElim | , |
"Number of trivial PHIs eliminated" | |||
) |
STATISTIC | ( | NumRetsDup | , |
"Number of return instructions duplicated" | |||
) |
STATISTIC | ( | NumSelectsExpanded | , |
"Number of selects turned into branches" | |||
) |
STATISTIC | ( | NumStoreExtractExposed | , |
"Number of store(extractelement) exposed" | |||
) |
Many architectures use the same instruction for both subtract and cmp.
Try to swap cmp operands to match subtract operations to allow for CSE.
Definition at line 1917 of file CodeGenPrepare.cpp.
References llvm::Value::getType(), llvm::Type::isIntegerTy(), llvm::PatternMatch::m_Specific(), llvm::PatternMatch::m_Sub(), llvm::PatternMatch::match(), and llvm::Value::users().
|
static |
Definition at line 8255 of file CodeGenPrepare.cpp.
References GEPSequentialConstIndexed(), llvm::TargetTransformInfo::getIntImmCost(), llvm::User::getOperand(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::BasicBlock::getTerminator(), llvm::Value::getType(), llvm::ConstantInt::getValue(), llvm::none_of(), llvm::TargetTransformInfo::TCC_Basic, llvm::TargetTransformInfo::TCK_SizeAndLatency, and llvm::Value::users().
|
static |
|
static |
|
static |
|
static |
|
static |
|
static |
|
static |
|
static |
DEBUG_TYPE |
Definition at line 539 of file CodeGenPrepare.cpp.
|
static |
|
static |
|
static |
|
static |
|
static |
|
static |
|
static |
|
static |
|
static |
|
static |
|
static |
Referenced by foldICmpWithDominatingICmp().
|
static |
Optimize for code false |
Definition at line 540 of file CodeGenPrepare.cpp.
|
static |
Referenced by splitMergedValStore().
|
static |
Optimize for code generation |
Definition at line 540 of file CodeGenPrepare.cpp.
Referenced by StackNode::childGeneration().
|
static |
|
static |
Referenced by FindAllMemoryUses().
|
static |
|
static |
|
static |
|
static |
|
static |