CorrelatedValuePropagation.cpp File Reference

#include "llvm/Transforms/Scalar/CorrelatedValuePropagation.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/DomTreeUpdater.h"
#include "llvm/Analysis/GlobalsModRef.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/LazyValueInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/PassManager.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/Value.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Transforms/Utils/Local.h"
#include <cassert>
#include <optional>
#include <utility>

Go to the source code of this file.

Macros
#define	DEBUG_TYPE   "correlated-value-propagation"

Enumerations
enum class	Domain { NonNegative , NonPositive , Unknown }

Functions
	STATISTIC (NumPhis, "Number of phis propagated")
	STATISTIC (NumPhiCommon, "Number of phis deleted via common incoming value")
	STATISTIC (NumSelects, "Number of selects propagated")
	STATISTIC (NumMemAccess, "Number of memory access targets propagated")
	STATISTIC (NumCmps, "Number of comparisons propagated")
	STATISTIC (NumReturns, "Number of return values propagated")
	STATISTIC (NumDeadCases, "Number of switch cases removed")
	STATISTIC (NumSDivSRemsNarrowed, "Number of sdivs/srems whose width was decreased")
	STATISTIC (NumSDivs, "Number of sdiv converted to udiv")
	STATISTIC (NumUDivURemsNarrowed, "Number of udivs/urems whose width was decreased")
	STATISTIC (NumAShrsConverted, "Number of ashr converted to lshr")
	STATISTIC (NumAShrsRemoved, "Number of ashr removed")
	STATISTIC (NumSRems, "Number of srem converted to urem")
	STATISTIC (NumSExt, "Number of sext converted to zext")
	STATISTIC (NumSICmps, "Number of signed icmp preds simplified to unsigned")
	STATISTIC (NumAnd, "Number of ands removed")
	STATISTIC (NumNW, "Number of no-wrap deductions")
	STATISTIC (NumNSW, "Number of no-signed-wrap deductions")
	STATISTIC (NumNUW, "Number of no-unsigned-wrap deductions")
	STATISTIC (NumAddNW, "Number of no-wrap deductions for add")
	STATISTIC (NumAddNSW, "Number of no-signed-wrap deductions for add")
	STATISTIC (NumAddNUW, "Number of no-unsigned-wrap deductions for add")
	STATISTIC (NumSubNW, "Number of no-wrap deductions for sub")
	STATISTIC (NumSubNSW, "Number of no-signed-wrap deductions for sub")
	STATISTIC (NumSubNUW, "Number of no-unsigned-wrap deductions for sub")
	STATISTIC (NumMulNW, "Number of no-wrap deductions for mul")
	STATISTIC (NumMulNSW, "Number of no-signed-wrap deductions for mul")
	STATISTIC (NumMulNUW, "Number of no-unsigned-wrap deductions for mul")
	STATISTIC (NumShlNW, "Number of no-wrap deductions for shl")
	STATISTIC (NumShlNSW, "Number of no-signed-wrap deductions for shl")
	STATISTIC (NumShlNUW, "Number of no-unsigned-wrap deductions for shl")
	STATISTIC (NumAbs, "Number of llvm.abs intrinsics removed")
	STATISTIC (NumOverflows, "Number of overflow checks removed")
	STATISTIC (NumSaturating, "Number of saturating arithmetics converted to normal arithmetics")
	STATISTIC (NumNonNull, "Number of function pointer arguments marked non-null")
	STATISTIC (NumMinMax, "Number of llvm.[us]{min,max} intrinsics removed")
	STATISTIC (NumUDivURemsNarrowedExpanded, "Number of bound udiv's/urem's expanded")
static bool	processSelect (SelectInst *S, LazyValueInfo *LVI)
static bool	simplifyCommonValuePhi (PHINode *P, LazyValueInfo *LVI, DominatorTree *DT)
	Try to simplify a phi with constant incoming values that match the edge values of a non-constant value on all other edges: bb0: isnull = icmp eq i8* x, null br i1 isnull, label bb2, label bb1 bb1: br label bb2 bb2: r = phi i8* [ x, bb1 ], [ null, bb0 ] --> r = x.
static Value *	getValueOnEdge (LazyValueInfo *LVI, Value *Incoming, BasicBlock *From, BasicBlock *To, Instruction *CxtI)
static bool	processPHI (PHINode *P, LazyValueInfo *LVI, DominatorTree *DT, const SimplifyQuery &SQ)
static bool	processMemAccess (Instruction *I, LazyValueInfo *LVI)
static bool	processICmp (ICmpInst *Cmp, LazyValueInfo *LVI)
static bool	constantFoldCmp (CmpInst *Cmp, LazyValueInfo *LVI)
	See if LazyValueInfo's ability to exploit edge conditions or range information is sufficient to prove this comparison.
static bool	processCmp (CmpInst *Cmp, LazyValueInfo *LVI)
static bool	processSwitch (SwitchInst *I, LazyValueInfo *LVI, DominatorTree *DT)
	Simplify a switch instruction by removing cases which can never fire.
static bool	willNotOverflow (BinaryOpIntrinsic *BO, LazyValueInfo *LVI)
static void	setDeducedOverflowingFlags (Value *V, Instruction::BinaryOps Opcode, bool NewNSW, bool NewNUW)
static bool	processBinOp (BinaryOperator *BinOp, LazyValueInfo *LVI)
static bool	processAbsIntrinsic (IntrinsicInst *II, LazyValueInfo *LVI)
static bool	processMinMaxIntrinsic (MinMaxIntrinsic *MM, LazyValueInfo *LVI)
static bool	processOverflowIntrinsic (WithOverflowInst *WO, LazyValueInfo *LVI)
static bool	processSaturatingInst (SaturatingInst *SI, LazyValueInfo *LVI)
static bool	processCallSite (CallBase &CB, LazyValueInfo *LVI)
	Infer nonnull attributes for the arguments at the specified callsite.
static Domain	getDomain (const ConstantRange &CR)
static bool	narrowSDivOrSRem (BinaryOperator *Instr, const ConstantRange &LCR, const ConstantRange &RCR)
	Try to shrink a sdiv/srem's width down to the smallest power of two that's sufficient to contain its operands.
static bool	expandUDivOrURem (BinaryOperator *Instr, const ConstantRange &XCR, const ConstantRange &YCR)
static bool	narrowUDivOrURem (BinaryOperator *Instr, const ConstantRange &XCR, const ConstantRange &YCR)
	Try to shrink a udiv/urem's width down to the smallest power of two that's sufficient to contain its operands.
static bool	processUDivOrURem (BinaryOperator *Instr, LazyValueInfo *LVI)
static bool	processSRem (BinaryOperator *SDI, const ConstantRange &LCR, const ConstantRange &RCR, LazyValueInfo *LVI)
static bool	processSDiv (BinaryOperator *SDI, const ConstantRange &LCR, const ConstantRange &RCR, LazyValueInfo *LVI)
	See if LazyValueInfo's ability to exploit edge conditions or range information is sufficient to prove the signs of both operands of this SDiv.
static bool	processSDivOrSRem (BinaryOperator *Instr, LazyValueInfo *LVI)
static bool	processAShr (BinaryOperator *SDI, LazyValueInfo *LVI)
static bool	processSExt (SExtInst *SDI, LazyValueInfo *LVI)
static bool	processAnd (BinaryOperator *BinOp, LazyValueInfo *LVI)
static Constant *	getConstantAt (Value *V, Instruction *At, LazyValueInfo *LVI)
static bool	runImpl (Function &F, LazyValueInfo *LVI, DominatorTree *DT, const SimplifyQuery &SQ)

Variables
static cl::opt< bool >	CanonicalizeICmpPredicatesToUnsigned ("canonicalize-icmp-predicates-to-unsigned", cl::init(true), cl::Hidden, cl::desc("Enables canonicalization of signed relational predicates to " "unsigned (e.g. sgt => ugt)"))

Macro Definition Documentation

DEBUG_TYPE

#define DEBUG_TYPE   "correlated-value-propagation"

Definition at line 48 of file CorrelatedValuePropagation.cpp.

Enumeration Type Documentation

Domain

enum class Domain

strong

Enumerator
NonNegative
NonPositive
Unknown

Definition at line 656 of file CorrelatedValuePropagation.cpp.

Function Documentation

constantFoldCmp()

static bool constantFoldCmp ( CmpInst *  Cmp, LazyValueInfo *  LVI  )

static

See if LazyValueInfo's ability to exploit edge conditions or range information is sufficient to prove this comparison.

Even for local conditions, this can sometimes prove conditions instcombine can't by exploiting range information.

Definition at line 303 of file CorrelatedValuePropagation.cpp.

References llvm::ConstantInt::get(), llvm::LazyValueInfo::getPredicateAt(), llvm::Value::getType(), llvm::CmpInst::makeCmpResultType(), and llvm::LazyValueInfo::Unknown.

Referenced by processCmp().

expandUDivOrURem()

static bool expandUDivOrURem ( BinaryOperator *  Instr, const ConstantRange &  XCR, const ConstantRange &  YCR  )

static

Definition at line 715 of file CorrelatedValuePropagation.cpp.

References assert(), B, llvm::Instruction::eraseFromParent(), llvm::ConstantRange::getBitWidth(), llvm::Value::getName(), llvm::Constant::getNullValue(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::Value::getType(), llvm::ConstantRange::icmp(), llvm::ConstantRange::isAllNegative(), llvm::Type::isVectorTy(), llvm::Value::replaceAllUsesWith(), llvm::Value::takeName(), llvm::ConstantRange::umul_sat(), X, and Y.

Referenced by processUDivOrURem().

getConstantAt()

static Constant * getConstantAt ( Value *  V, Instruction *  At, LazyValueInfo *  LVI  )

static

Definition at line 1078 of file CorrelatedValuePropagation.cpp.

References llvm::CallingConv::C, llvm::LazyValueInfo::getConstant(), llvm::ConstantInt::getFalse(), llvm::LazyValueInfo::getPredicateAt(), llvm::ConstantInt::getTrue(), llvm::LazyValueInfo::True, and llvm::LazyValueInfo::Unknown.

Referenced by runImpl().

getDomain()

static Domain getDomain ( const ConstantRange &  CR )

static

Definition at line 658 of file CorrelatedValuePropagation.cpp.

References llvm::ConstantRange::getBitWidth(), llvm::APInt::getZero(), llvm::ConstantRange::icmp(), llvm::ConstantRange::isAllNonNegative(), NonNegative, NonPositive, and Unknown.

Referenced by collectMDInDomain(), llvm::MDNode::getMostGenericAliasScope(), processSDiv(), and processSRem().

getValueOnEdge()

static Value * getValueOnEdge ( LazyValueInfo *  LVI, Value *  Incoming, BasicBlock *  From, BasicBlock *  To, Instruction *  CxtI  )

static

Definition at line 178 of file CorrelatedValuePropagation.cpp.

References llvm::CallingConv::C, llvm::LazyValueInfo::False, From, llvm::LazyValueInfo::getConstantOnEdge(), llvm::LazyValueInfo::getPredicateOnEdge(), llvm::Value::getType(), llvm::Type::isVectorTy(), and SI.

Referenced by processPHI().

narrowSDivOrSRem()

static bool narrowSDivOrSRem ( BinaryOperator *  Instr, const ConstantRange &  LCR, const ConstantRange &  RCR  )

static

Try to shrink a sdiv/srem's width down to the smallest power of two that's sufficient to contain its operands.

Definition at line 668 of file CorrelatedValuePropagation.cpp.

References assert(), B, llvm::ConstantRange::contains(), llvm::Instruction::eraseFromParent(), llvm::APInt::getAllOnes(), llvm::Value::getContext(), llvm::Type::getIntegerBitWidth(), llvm::Type::getIntNTy(), llvm::ConstantRange::getMinSignedBits(), llvm::Value::getName(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::APInt::getSignedMinValue(), llvm::Value::getType(), llvm::Instruction::isExact(), llvm::Type::isVectorTy(), LHS, llvm::PowerOf2Ceil(), llvm::Value::replaceAllUsesWith(), RHS, and llvm::APInt::sext().

Referenced by processSDivOrSRem().

narrowUDivOrURem()

static bool narrowUDivOrURem ( BinaryOperator *  Instr, const ConstantRange &  XCR, const ConstantRange &  YCR  )

static

Try to shrink a udiv/urem's width down to the smallest power of two that's sufficient to contain its operands.

Definition at line 788 of file CorrelatedValuePropagation.cpp.

References assert(), B, llvm::Instruction::eraseFromParent(), llvm::ConstantRange::getActiveBits(), llvm::Value::getContext(), llvm::Type::getIntegerBitWidth(), llvm::Type::getIntNTy(), llvm::Value::getName(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::Value::getType(), llvm::Instruction::isExact(), llvm::Type::isVectorTy(), LHS, llvm::PowerOf2Ceil(), llvm::Value::replaceAllUsesWith(), and RHS.

Referenced by processUDivOrURem().

processAbsIntrinsic()

static bool processAbsIntrinsic ( IntrinsicInst *  II, LazyValueInfo *  LVI  )

static

Definition at line 461 of file CorrelatedValuePropagation.cpp.

References assert(), B, llvm::Instruction::eraseFromParent(), llvm::LazyValueInfo::False, llvm::ConstantInt::get(), llvm::CallBase::getArgOperand(), llvm::Value::getContext(), llvm::Value::getName(), llvm::LazyValueInfo::getPredicateAt(), llvm::Type::getScalarSizeInBits(), llvm::APInt::getSignedMinValue(), llvm::ConstantInt::getTrue(), processBinOp(), llvm::Value::replaceAllUsesWith(), llvm::CallBase::setArgOperand(), llvm::LazyValueInfo::True, llvm::LazyValueInfo::Unknown, and X.

Referenced by processCallSite().

processAnd()

static bool processAnd ( BinaryOperator *  BinOp, LazyValueInfo *  LVI  )

static

Definition at line 1053 of file CorrelatedValuePropagation.cpp.

References llvm::Instruction::eraseFromParent(), llvm::LazyValueInfo::getConstantRangeAtUse(), llvm::User::getOperand(), llvm::User::getOperandUse(), llvm::Value::getType(), llvm::ConstantRange::getUnsignedMax(), llvm::Type::isVectorTy(), LHS, llvm::Value::replaceAllUsesWith(), RHS, and llvm::APInt::ule().

Referenced by runImpl().

processAShr()

static bool processAShr ( BinaryOperator *  SDI, LazyValueInfo *  LVI  )

static

Definition at line 966 of file CorrelatedValuePropagation.cpp.

References llvm::ConstantRange::contains(), llvm::Instruction::eraseFromParent(), llvm::LazyValueInfo::getConstantRangeAtUse(), llvm::Instruction::getDebugLoc(), llvm::Type::getIntegerBitWidth(), llvm::User::getOperand(), llvm::User::getOperandUse(), llvm::Value::getType(), llvm::ConstantRange::isAllNonNegative(), llvm::Instruction::isExact(), llvm::Type::isVectorTy(), and llvm::Value::replaceAllUsesWith().

Referenced by runImpl().

processBinOp()

static bool processBinOp ( BinaryOperator *  BinOp, LazyValueInfo *  LVI  )

static

Definition at line 1015 of file CorrelatedValuePropagation.cpp.

References llvm::ConstantRange::contains(), llvm::LazyValueInfo::getConstantRange(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::Value::getType(), llvm::Instruction::hasNoSignedWrap(), llvm::Instruction::hasNoUnsignedWrap(), llvm::Type::isVectorTy(), LHS, llvm::ConstantRange::makeGuaranteedNoWrapRegion(), RHS, and setDeducedOverflowingFlags().

Referenced by processAbsIntrinsic(), processOverflowIntrinsic(), processSaturatingInst(), and runImpl().

processCallSite()

static bool processCallSite ( CallBase &  CB, LazyValueInfo *  LVI  )

static

Infer nonnull attributes for the arguments at the specified callsite.

Definition at line 579 of file CorrelatedValuePropagation.cpp.

References llvm::AttributeList::addParamAttribute(), llvm::CallBase::arg_size(), llvm::CallBase::args(), assert(), llvm::CallingConv::C, llvm::SmallVectorBase< Size_T >::empty(), llvm::LazyValueInfo::False, llvm::Attribute::get(), llvm::ConstantPointerNull::get(), llvm::CallBase::getAttributes(), llvm::LazyValueInfo::getConstant(), llvm::Value::getContext(), llvm::CallBase::getIntrinsicID(), llvm::CallBase::getOperandBundle(), llvm::LazyValueInfo::getPredicateAt(), llvm::LLVMContext::OB_deopt, llvm::CallBase::paramHasAttr(), processAbsIntrinsic(), processMinMaxIntrinsic(), processOverflowIntrinsic(), processSaturatingInst(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::CallBase::setAttributes(), SI, llvm::SmallVectorBase< Size_T >::size(), and willNotOverflow().

Referenced by runImpl().

processCmp()

static bool processCmp ( CmpInst *  Cmp, LazyValueInfo *  LVI  )

static

Definition at line 320 of file CorrelatedValuePropagation.cpp.

References constantFoldCmp(), and processICmp().

Referenced by runImpl().

processICmp()

static bool processICmp ( ICmpInst *  Cmp, LazyValueInfo *  LVI  )

static

Definition at line 273 of file CorrelatedValuePropagation.cpp.

References CanonicalizeICmpPredicatesToUnsigned, llvm::LazyValueInfo::getConstantRange(), and llvm::ConstantRange::getEquivalentPredWithFlippedSignedness().

Referenced by processCmp().

processMemAccess()

static bool processMemAccess ( Instruction *  I, LazyValueInfo *  LVI  )

static

Definition at line 256 of file CorrelatedValuePropagation.cpp.

References llvm::CallingConv::C, llvm::LazyValueInfo::getConstant(), and I.

Referenced by runImpl().

processMinMaxIntrinsic()

static bool processMinMaxIntrinsic ( MinMaxIntrinsic *  MM, LazyValueInfo *  LVI  )

static

Definition at line 518 of file CorrelatedValuePropagation.cpp.

References llvm::Instruction::eraseFromParent(), llvm::MinMaxIntrinsic::getLHS(), llvm::CmpInst::getNonStrictPredicate(), llvm::User::getOperand(), llvm::MinMaxIntrinsic::getPredicate(), llvm::LazyValueInfo::getPredicateAt(), llvm::MinMaxIntrinsic::getRHS(), llvm::Value::replaceAllUsesWith(), and llvm::LazyValueInfo::Unknown.

Referenced by processCallSite().

processOverflowIntrinsic()

static bool processOverflowIntrinsic ( WithOverflowInst *  WO, LazyValueInfo *  LVI  )

static

Definition at line 532 of file CorrelatedValuePropagation.cpp.

References B, llvm::Instruction::eraseFromParent(), llvm::ConstantStruct::get(), llvm::PoisonValue::get(), llvm::BinaryOpIntrinsic::getBinaryOp(), llvm::ConstantInt::getFalse(), llvm::BinaryOpIntrinsic::getLHS(), llvm::Value::getName(), llvm::BinaryOpIntrinsic::getRHS(), llvm::Value::getType(), llvm::BinaryOpIntrinsic::isSigned(), processBinOp(), llvm::Value::replaceAllUsesWith(), setDeducedOverflowingFlags(), and Struct.

Referenced by processCallSite().

processPHI()

static bool processPHI ( PHINode *  P, LazyValueInfo *  LVI, DominatorTree *  DT, const SimplifyQuery &  SQ  )

static

Definition at line 225 of file CorrelatedValuePropagation.cpp.

References getValueOnEdge(), P, simplifyCommonValuePhi(), and llvm::simplifyInstruction().

Referenced by runImpl().

processSaturatingInst()

static bool processSaturatingInst ( SaturatingInst *  SI, LazyValueInfo *  LVI  )

static

Definition at line 558 of file CorrelatedValuePropagation.cpp.

References llvm::BinaryOperator::Create(), processBinOp(), llvm::Instruction::setDebugLoc(), setDeducedOverflowingFlags(), and SI.

Referenced by processCallSite().

processSDiv()

static bool processSDiv ( BinaryOperator *  SDI, const ConstantRange &  LCR, const ConstantRange &  RCR, LazyValueInfo *  LVI  )

static

See if LazyValueInfo's ability to exploit edge conditions or range information is sufficient to prove the signs of both operands of this SDiv.

If this is the case, replace the SDiv with a UDiv. Even for local conditions, this can sometimes prove conditions instcombine can't by exploiting range information.

Definition at line 899 of file CorrelatedValuePropagation.cpp.

References assert(), llvm::BinaryOperator::CreateNeg(), D, llvm::Instruction::eraseFromParent(), llvm::Instruction::getDebugLoc(), getDomain(), llvm::Value::getName(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::Value::getType(), llvm::Instruction::isExact(), llvm::Type::isVectorTy(), NonNegative, processUDivOrURem(), llvm::Value::replaceAllUsesWith(), and Unknown.

Referenced by processSDivOrSRem().

processSDivOrSRem()

static bool processSDivOrSRem ( BinaryOperator *  Instr, LazyValueInfo *  LVI  )

static

Definition at line 946 of file CorrelatedValuePropagation.cpp.

References assert(), llvm::LazyValueInfo::getConstantRangeAtUse(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperandUse(), llvm::Value::getType(), llvm::Type::isVectorTy(), narrowSDivOrSRem(), processSDiv(), and processSRem().

Referenced by runImpl().

processSelect()

static bool processSelect ( SelectInst *  S, LazyValueInfo *  LVI  )

static

Definition at line 97 of file CorrelatedValuePropagation.cpp.

References llvm::CallingConv::C, llvm::Instruction::eraseFromParent(), llvm::SelectInst::getCondition(), llvm::LazyValueInfo::getConstant(), llvm::SelectInst::getFalseValue(), llvm::SelectInst::getTrueValue(), llvm::Value::getType(), llvm::ConstantInt::isOne(), llvm::Type::isVectorTy(), and llvm::Value::replaceAllUsesWith().

Referenced by runImpl().

processSExt()

static bool processSExt ( SExtInst *  SDI, LazyValueInfo *  LVI  )

static

Definition at line 997 of file CorrelatedValuePropagation.cpp.

References llvm::sampleprof::Base, llvm::CastInst::CreateZExtOrBitCast(), llvm::Instruction::eraseFromParent(), llvm::LazyValueInfo::getConstantRangeAtUse(), llvm::Instruction::getDebugLoc(), llvm::User::getOperandUse(), llvm::Value::getType(), llvm::ConstantRange::isAllNonNegative(), llvm::Type::isVectorTy(), and llvm::Value::replaceAllUsesWith().

Referenced by runImpl().

processSRem()

static bool processSRem ( BinaryOperator *  SDI, const ConstantRange &  LCR, const ConstantRange &  RCR, LazyValueInfo *  LVI  )

static

Definition at line 840 of file CorrelatedValuePropagation.cpp.

References llvm::ConstantRange::abs(), assert(), llvm::BinaryOperator::CreateNeg(), D, llvm::Instruction::eraseFromParent(), llvm::Instruction::getDebugLoc(), getDomain(), llvm::Value::getName(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::Value::getType(), llvm::ConstantRange::icmp(), llvm::CmpInst::ICMP_ULT, llvm::Type::isVectorTy(), NonNegative, NonPositive, processUDivOrURem(), llvm::Value::replaceAllUsesWith(), and Unknown.

Referenced by processSDivOrSRem().

processSwitch()

static bool processSwitch ( SwitchInst *  I, LazyValueInfo *  LVI, DominatorTree *  DT  )

static

Simplify a switch instruction by removing cases which can never fire.

If the uselessness of a case could be determined locally then constant propagation would already have figured it out. Instead, walk the predecessors and statically evaluate cases based on information available on that edge. Cases that cannot fire no matter what the incoming edge can safely be removed. If a case fires on every incoming edge then the entire switch can be removed and replaced with a branch to the case destination.

Definition at line 338 of file CorrelatedValuePropagation.cpp.

References llvm::DomTreeUpdater::applyUpdatesPermissive(), Cond, llvm::ConstantFoldTerminator(), llvm::LazyValueInfo::False, llvm::LazyValueInfo::getPredicateAt(), I, llvm::CmpInst::ICMP_EQ, llvm::BasicBlock::removePredecessor(), SI, llvm::successors(), and llvm::LazyValueInfo::True.

Referenced by runImpl().

processUDivOrURem()

static bool processUDivOrURem ( BinaryOperator *  Instr, LazyValueInfo *  LVI  )

static

Definition at line 826 of file CorrelatedValuePropagation.cpp.

References assert(), expandUDivOrURem(), llvm::LazyValueInfo::getConstantRangeAtUse(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperandUse(), llvm::Value::getType(), llvm::Type::isVectorTy(), and narrowUDivOrURem().

Referenced by processSDiv(), processSRem(), and runImpl().

runImpl()

static bool runImpl ( Function &  F, LazyValueInfo *  LVI, DominatorTree *  DT, const SimplifyQuery &  SQ  )

static

Definition at line 1101 of file CorrelatedValuePropagation.cpp.

References llvm::CallingConv::C, llvm::depth_first(), F, getConstantAt(), llvm::make_early_inc_range(), processAnd(), processAShr(), processBinOp(), processCallSite(), processCmp(), processMemAccess(), processPHI(), processSDivOrSRem(), processSelect(), processSExt(), processSwitch(), and processUDivOrURem().

setDeducedOverflowingFlags()

static void setDeducedOverflowingFlags ( Value *  V, Instruction::BinaryOps  Opcode, bool  NewNSW, bool  NewNUW  )

static

Definition at line 409 of file CorrelatedValuePropagation.cpp.

References llvm_unreachable.

Referenced by processBinOp(), processOverflowIntrinsic(), and processSaturatingInst().

simplifyCommonValuePhi()

static bool simplifyCommonValuePhi ( PHINode *  P, LazyValueInfo *  LVI, DominatorTree *  DT  )

static

Try to simplify a phi with constant incoming values that match the edge values of a non-constant value on all other edges: bb0: isnull = icmp eq i8* x, null br i1 isnull, label bb2, label bb1 bb1: br label bb2 bb2: r = phi i8* [ x, bb1 ], [ null, bb0 ] --> r = x.

Definition at line 127 of file CorrelatedValuePropagation.cpp.

References llvm::CallingConv::C, llvm::DominatorTree::dominates(), llvm::SmallVectorBase< Size_T >::empty(), llvm::LazyValueInfo::getConstantOnEdge(), llvm::isGuaranteedNotToBePoison(), P, and llvm::SmallVectorTemplateBase< T, bool >::push_back().

Referenced by processPHI().

STATISTIC() [1/37]

STATISTIC	(	NumAbs	,
		"Number of llvm.abs intrinsics removed"
	)

STATISTIC() [2/37]

STATISTIC	(	NumAddNSW	,
		"Number of no-signed-wrap deductions for add"
	)

STATISTIC() [3/37]

STATISTIC	(	NumAddNUW	,
		"Number of no-unsigned-wrap deductions for add"
	)

STATISTIC() [4/37]

STATISTIC	(	NumAddNW	,
		"Number of no-wrap deductions for add"
	)

STATISTIC() [5/37]

STATISTIC	(	NumAnd	,
		"Number of ands removed"
	)

STATISTIC() [6/37]

STATISTIC	(	NumAShrsConverted	,
		"Number of ashr converted to lshr"
	)

STATISTIC() [7/37]

STATISTIC	(	NumAShrsRemoved	,
		"Number of ashr removed"
	)

STATISTIC() [8/37]

STATISTIC	(	NumCmps	,
		"Number of comparisons propagated"
	)

STATISTIC() [9/37]

STATISTIC	(	NumDeadCases	,
		"Number of switch cases removed"
	)

STATISTIC() [10/37]

STATISTIC	(	NumMemAccess	,
		"Number of memory access targets propagated"
	)

STATISTIC() [11/37]

STATISTIC	(	NumMinMax	,
		"Number of llvm.{min,max} intrinsics removed"	[us]
	)

STATISTIC() [12/37]

STATISTIC	(	NumMulNSW	,
		"Number of no-signed-wrap deductions for mul"
	)

STATISTIC() [13/37]

STATISTIC	(	NumMulNUW	,
		"Number of no-unsigned-wrap deductions for mul"
	)

STATISTIC() [14/37]

STATISTIC	(	NumMulNW	,
		"Number of no-wrap deductions for mul"
	)

STATISTIC() [15/37]

STATISTIC	(	NumNonNull	,
		"Number of function pointer arguments marked non-null"
	)

STATISTIC() [16/37]

STATISTIC	(	NumNSW	,
		"Number of no-signed-wrap deductions"
	)

STATISTIC() [17/37]

STATISTIC	(	NumNUW	,
		"Number of no-unsigned-wrap deductions"
	)

STATISTIC() [18/37]

STATISTIC	(	NumNW	,
		"Number of no-wrap deductions"
	)

STATISTIC() [19/37]

STATISTIC	(	NumOverflows	,
		"Number of overflow checks removed"
	)

STATISTIC() [20/37]

STATISTIC	(	NumPhiCommon	,
		"Number of phis deleted via common incoming value"
	)

STATISTIC() [21/37]

STATISTIC	(	NumPhis	,
		"Number of phis propagated"
	)

STATISTIC() [22/37]

STATISTIC	(	NumReturns	,
		"Number of return values propagated"
	)

STATISTIC() [23/37]

STATISTIC	(	NumSaturating	,
		"Number of saturating arithmetics converted to normal arithmetics"
	)

STATISTIC() [24/37]

STATISTIC	(	NumSDivs	,
		"Number of sdiv converted to udiv"
	)

STATISTIC() [25/37]

STATISTIC	(	NumSDivSRemsNarrowed	,
		"Number of sdivs/srems whose width was decreased"
	)

STATISTIC() [26/37]

STATISTIC	(	NumSelects	,
		"Number of selects propagated"
	)

STATISTIC() [27/37]

STATISTIC	(	NumSExt	,
		"Number of sext converted to zext"
	)

STATISTIC() [28/37]

STATISTIC	(	NumShlNSW	,
		"Number of no-signed-wrap deductions for shl"
	)

STATISTIC() [29/37]

STATISTIC	(	NumShlNUW	,
		"Number of no-unsigned-wrap deductions for shl"
	)

STATISTIC() [30/37]

STATISTIC	(	NumShlNW	,
		"Number of no-wrap deductions for shl"
	)

STATISTIC() [31/37]

STATISTIC	(	NumSICmps	,
		"Number of signed icmp preds simplified to unsigned"
	)

STATISTIC() [32/37]

STATISTIC	(	NumSRems	,
		"Number of srem converted to urem"
	)

STATISTIC() [33/37]

STATISTIC	(	NumSubNSW	,
		"Number of no-signed-wrap deductions for sub"
	)

STATISTIC() [34/37]

STATISTIC	(	NumSubNUW	,
		"Number of no-unsigned-wrap deductions for sub"
	)

STATISTIC() [35/37]

STATISTIC	(	NumSubNW	,
		"Number of no-wrap deductions for sub"
	)

STATISTIC() [36/37]

STATISTIC	(	NumUDivURemsNarrowed	,
		"Number of udivs/urems whose width was decreased"
	)

STATISTIC() [37/37]

STATISTIC	(	NumUDivURemsNarrowedExpanded	,
		"Number of bound udiv's/urem's expanded"
	)

willNotOverflow()

static bool willNotOverflow ( BinaryOpIntrinsic *  BO, LazyValueInfo *  LVI  )

static

Definition at line 401 of file CorrelatedValuePropagation.cpp.

References llvm::ConstantRange::contains(), llvm::BinaryOpIntrinsic::getBinaryOp(), llvm::LazyValueInfo::getConstantRangeAtUse(), llvm::BinaryOpIntrinsic::getNoWrapKind(), llvm::User::getOperandUse(), and llvm::ConstantRange::makeGuaranteedNoWrapRegion().

Referenced by processCallSite().

Variable Documentation

CanonicalizeICmpPredicatesToUnsigned

cl::opt< bool > CanonicalizeICmpPredicatesToUnsigned("canonicalize-icmp-predicates-to-unsigned", cl::init(true), cl::Hidden, cl::desc("Enables canonicalization of signed relational predicates to " "unsigned (e.g. sgt => ugt)")) ( "canonicalize-icmp-predicates-to-unsigned"  , cl::init(true)  , cl::Hidden  , cl::desc("Enables canonicalization of signed relational predicates to " "unsigned (e.g. sgt => ugt)")    )

static

Referenced by processICmp().