LazyValueInfo.cpp File Reference

#include "llvm/Analysis/LazyValueInfo.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Analysis/AssumeBundleQueries.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/Passes.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/ValueLattice.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/AssemblyAnnotationWriter.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/InitializePasses.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/KnownBits.h"
#include "llvm/Support/raw_ostream.h"
#include <optional>

Go to the source code of this file.

Classes
class	llvm::LazyValueInfoImpl

Namespaces
namespace	llvm
	This is an optimization pass for GlobalISel generic memory operations.

Macros
#define	DEBUG_TYPE   "lazy-value-info"

Functions
	INITIALIZE_PASS_BEGIN (LazyValueInfoWrapperPass, "lazy-value-info", "Lazy Value Information Analysis", false, true) INITIALIZE_PASS_END(LazyValueInfoWrapperPass
lazy value Lazy Value Information static true cl::opt< bool >	PerPredRanges ("lvi-per-pred-ranges", cl::Hidden, cl::init(false), cl::desc("Enable tracking of ranges for a value in a block for" "each block predecessor (default = false)"))
LLVM_ABI FunctionPass *	llvm::createLazyValueInfoPass ()
	createLazyValueInfoPass - This creates an instance of the LazyValueInfo pass.
static bool	hasSingleValue (const ValueLatticeElement &Val)
	Returns true if this lattice value represents at most one possible value.
static ValueLatticeElement	getFromRangeMetadata (Instruction *BBI)
static void	AddNonNullPointer (Value *Ptr, NonNullPointerSet &PtrSet, bool IsDereferenced=true)
static void	AddNonNullPointersByInstruction (Instruction *I, NonNullPointerSet &PtrSet)
static bool	matchICmpOperand (APInt &Offset, Value *LHS, Value *Val, ICmpInst::Predicate Pred)
static std::optional< ConstantRange >	getRangeViaSLT (CmpInst::Predicate Pred, APInt RHS, function_ref< std::optional< ConstantRange >(const APInt &)> Fn)
static ValueLatticeElement	getValueFromICmpCtpop (ICmpInst::Predicate Pred, Value *RHS)
	Get value range for a "ctpop(Val) Pred RHS" condition.
static ValueLatticeElement	getValueFromOverflowCondition (Value *Val, WithOverflowInst *WO, bool IsTrueDest)
static bool	usesOperand (User *Usr, Value *Op)
static bool	isOperationFoldable (User *Usr)
static ValueLatticeElement	constantFoldUser (User *Usr, Value *Op, const APInt &OpConstVal, const DataLayout &DL)
static bool	isKnownNonConstant (Value *V)
	Returns true if we can statically tell that this value will never be a "useful" constant.
static Constant *	getPredicateResult (CmpInst::Predicate Pred, Constant *C, const ValueLatticeElement &Val, const DataLayout &DL)

Variables
static const unsigned	MaxProcessedPerValue = 500
lazy value	info
lazy value Lazy Value Information	Analysis
lazy value Lazy Value Information	false

Macro Definition Documentation

DEBUG_TYPE

#define DEBUG_TYPE   "lazy-value-info"

Definition at line 48 of file LazyValueInfo.cpp.

Function Documentation

AddNonNullPointer()

void AddNonNullPointer ( Value * Ptr, NonNullPointerSet & PtrSet, bool IsDereferenced = true )

static

Definition at line 673 of file LazyValueInfo.cpp.

References llvm::Type::getPointerAddressSpace(), llvm::Value::getType(), llvm::getUnderlyingObject(), and llvm::Value::stripInBoundsOffsets().

Referenced by AddNonNullPointersByInstruction().

AddNonNullPointersByInstruction()

void AddNonNullPointersByInstruction ( Instruction * I, NonNullPointerSet & PtrSet )

static

Definition at line 681 of file LazyValueInfo.cpp.

References AddNonNullPointer(), llvm::dyn_cast(), I, and MI.

constantFoldUser()

ValueLatticeElement constantFoldUser ( User * Usr, Value * Op, const APInt & OpConstVal, const DataLayout & DL )

static

Definition at line 1574 of file LazyValueInfo.cpp.

References assert(), llvm::CallingConv::C, llvm::cast(), DL, llvm::dyn_cast(), llvm::dyn_cast_or_null(), llvm::CastInst::getDestTy(), llvm::Constant::getIntegerValue(), llvm::BinaryOperator::getOpcode(), llvm::CastInst::getOpcode(), llvm::User::getOperand(), llvm::ValueLatticeElement::getOverdefined(), llvm::ValueLatticeElement::getRange(), llvm::isa(), isOperationFoldable(), LHS, RHS, llvm::simplifyBinOp(), and llvm::simplifyCastInst().

getFromRangeMetadata()

ValueLatticeElement getFromRangeMetadata ( Instruction * BBI )

static

Definition at line 589 of file LazyValueInfo.cpp.

References llvm::cast(), llvm::getConstantRangeFromMetadata(), llvm::Instruction::getMetadata(), llvm::Instruction::getOpcode(), llvm::ValueLatticeElement::getOverdefined(), llvm::getRange(), llvm::ValueLatticeElement::getRange(), llvm::Value::getType(), llvm::isa(), and Range.

Referenced by llvm::LazyValueInfoImpl::getValueAt().

getPredicateResult()

Constant * getPredicateResult ( CmpInst::Predicate Pred, Constant * C, const ValueLatticeElement & Val, const DataLayout & DL )

static

Definition at line 2049 of file LazyValueInfo.cpp.

References llvm::CallingConv::C, llvm::ConstantFoldCompareInstOperands(), DL, llvm::ValueLatticeElement::getConstant(), llvm::ValueLatticeElement::getConstantRange(), llvm::ConstantInt::getFalse(), llvm::CmpInst::getInversePredicate(), llvm::ValueLatticeElement::getNotConstant(), llvm::ConstantInt::getTrue(), llvm::ConstantRange::icmp(), llvm::CmpInst::ICMP_EQ, llvm::CmpInst::ICMP_NE, llvm::ValueLatticeElement::isConstant(), llvm::ValueLatticeElement::isConstantRange(), llvm::ValueLatticeElement::isNotConstant(), llvm::Constant::isNullValue(), llvm::CmpInst::makeCmpResultType(), and RHS.

Referenced by llvm::LazyValueInfo::getPredicateAt(), and llvm::LazyValueInfo::getPredicateOnEdge().

getRangeViaSLT()

std::optional< ConstantRange > getRangeViaSLT ( CmpInst::Predicate Pred, APInt RHS, function_ref< std::optional< ConstantRange >(const APInt &)> Fn )

static

Definition at line 1319 of file LazyValueInfo.cpp.

References assert(), llvm::CmpInst::getInversePredicate(), llvm::CmpInst::ICMP_SGE, llvm::CmpInst::ICMP_SGT, llvm::CmpInst::ICMP_SLE, llvm::CmpInst::ICMP_SLT, and RHS.

getValueFromICmpCtpop()

ValueLatticeElement getValueFromICmpCtpop ( ICmpInst::Predicate Pred, Value * RHS )

static

Get value range for a "ctpop(Val) Pred RHS" condition.

Definition at line 1339 of file LazyValueInfo.cpp.

References llvm::BitWidth, llvm::dyn_cast(), llvm::APInt::getHighBitsSet(), llvm::APInt::getLimitedValue(), llvm::APInt::getLowBitsSet(), llvm::ConstantRange::getNonEmpty(), llvm::ValueLatticeElement::getOverdefined(), llvm::ValueLatticeElement::getRange(), llvm::ConstantRange::getUnsignedMax(), llvm::ConstantRange::getUnsignedMin(), llvm::ConstantRange::makeExactICmpRegion(), and RHS.

getValueFromOverflowCondition()

ValueLatticeElement getValueFromOverflowCondition ( Value * Val, WithOverflowInst * WO, bool IsTrueDest )

static

Definition at line 1485 of file LazyValueInfo.cpp.

References llvm::CallingConv::C, llvm::BinaryOpIntrinsic::getBinaryOp(), llvm::BinaryOpIntrinsic::getLHS(), llvm::BinaryOpIntrinsic::getNoWrapKind(), llvm::ValueLatticeElement::getOverdefined(), llvm::ValueLatticeElement::getRange(), llvm::BinaryOpIntrinsic::getRHS(), llvm::ConstantRange::inverse(), llvm::PatternMatch::m_APInt(), llvm::ConstantRange::makeExactNoWrapRegion(), and llvm::PatternMatch::match().

hasSingleValue()

bool hasSingleValue ( const ValueLatticeElement & Val )

static

Returns true if this lattice value represents at most one possible value.

This is as precise as any lattice value can get while still representing reachable code.

Definition at line 79 of file LazyValueInfo.cpp.

References llvm::ValueLatticeElement::getConstantRange(), llvm::ValueLatticeElement::isConstant(), llvm::ValueLatticeElement::isConstantRange(), and llvm::ConstantRange::isSingleElement().

INITIALIZE_PASS_BEGIN()

INITIALIZE_PASS_BEGIN	(	LazyValueInfoWrapperPass	,
		"lazy-value-info"	,
		"Lazy Value Information Analysis"	,
		false	,
		true	)

References INITIALIZE_PASS_DEPENDENCY.

isKnownNonConstant()

bool isKnownNonConstant ( Value * V )

static

Returns true if we can statically tell that this value will never be a "useful" constant.

In practice, this means we've got something like an alloca or a malloc call for which a comparison against a constant can only be guarding dead code. Note that we are potentially giving up some precision in dead code (a constant result) in favour of avoiding a expensive search for a easily answered common query.

Definition at line 1976 of file LazyValueInfo.cpp.

References llvm::isa().

Referenced by llvm::LazyValueInfo::getConstant().

isOperationFoldable()

bool isOperationFoldable ( User * Usr )

static

Definition at line 1566 of file LazyValueInfo.cpp.

References llvm::isa().

Referenced by constantFoldUser().

matchICmpOperand()

bool matchICmpOperand ( APInt & Offset, Value * LHS, Value * Val, ICmpInst::Predicate Pred )

static

Definition at line 1261 of file LazyValueInfo.cpp.

References llvm::CallingConv::C, llvm::CmpInst::ICMP_UGE, llvm::CmpInst::ICMP_UGT, llvm::CmpInst::ICMP_ULE, llvm::CmpInst::ICMP_ULT, LHS, llvm::PatternMatch::m_AddLike(), llvm::PatternMatch::m_APInt(), llvm::PatternMatch::m_c_And(), llvm::PatternMatch::m_c_Or(), llvm::PatternMatch::m_Specific(), llvm::PatternMatch::m_Value(), llvm::PatternMatch::match(), and llvm::Offset.

PerPredRanges()

lazy value Lazy Value Information static true cl::opt< bool > PerPredRanges ( "lvi-per-pred-ranges" , cl::Hidden , cl::init(false) , cl::desc("Enable tracking of ranges for a value in a block for" "each block predecessor (default = false)")  )

static

References PerPredRanges().

Referenced by PerPredRanges().

usesOperand()

bool usesOperand ( User * Usr, Value * Op )

static

Definition at line 1558 of file LazyValueInfo.cpp.

References llvm::is_contained(), and llvm::User::operands().

Variable Documentation

Analysis

lazy value Lazy Value Information Analysis

Definition at line 61 of file LazyValueInfo.cpp.

false

lazy value Lazy Value Information false

Definition at line 61 of file LazyValueInfo.cpp.

info

lazy value info

Definition at line 60 of file LazyValueInfo.cpp.

Referenced by ARM64EmitRuntimeFunction(), ARM64EmitUnwindInfo(), ARM64EmitUnwindInfoForSegment(), ARM64FindSegmentsInFunction(), ARM64ProcessEpilogs(), ARMEmitRuntimeFunction(), ARMEmitUnwindInfo(), checkARM64PackedEpilog(), checkARMPackedEpilog(), EmitRuntimeFunction(), EmitUnwindInfo(), llvm::Win64EH::ARM64UnwindEmitter::EmitUnwindInfo(), llvm::Win64EH::ARMUnwindEmitter::EmitUnwindInfo(), llvm::Win64EH::UnwindEmitter::EmitUnwindInfo(), findLiveReferences(), FindMatchingEpilog(), llvm::CCState::getInRegsParamInfo(), llvm::TargetLowering::getMultipleConstraintMatchWeight(), llvm::ARMTargetLowering::getSingleConstraintMatchWeight(), llvm::AVRTargetLowering::getSingleConstraintMatchWeight(), llvm::PPCTargetLowering::getSingleConstraintMatchWeight(), llvm::SparcTargetLowering::getSingleConstraintMatchWeight(), llvm::TargetLowering::getSingleConstraintMatchWeight(), insertParsePoints(), llvm::opt::Option::Option(), recomputeLiveInValues(), llvm::MachO::swapStruct(), tryARM64PackedUnwind(), and tryARMPackedUnwind().

MaxProcessedPerValue

const unsigned MaxProcessedPerValue = 500

static

Definition at line 52 of file LazyValueInfo.cpp.