ConstantHoisting.cpp File Reference

#include "llvm/Transforms/Scalar/ConstantHoisting.h"
#include "llvm/ADT/APInt.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/BlockFrequencyInfo.h"
#include "llvm/Analysis/ProfileSummaryInfo.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfoMetadata.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.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/Value.h"
#include "llvm/InitializePasses.h"
#include "llvm/Pass.h"
#include "llvm/Support/BlockFrequency.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/SizeOpts.h"
#include <algorithm>
#include <cassert>
#include <cstdint>
#include <iterator>
#include <tuple>
#include <utility>

Go to the source code of this file.

Macros
#define	DEBUG_TYPE   "consthoist"

Functions
	STATISTIC (NumConstantsHoisted, "Number of constants hoisted")
	STATISTIC (NumConstantsRebased, "Number of constants rebased")
	INITIALIZE_PASS_BEGIN (ConstantHoistingLegacyPass, "consthoist", "Constant Hoisting", false, false) INITIALIZE_PASS_END(ConstantHoistingLegacyPass
static void	findBestInsertionSet (DominatorTree &DT, BlockFrequencyInfo &BFI, BasicBlock *Entry, SetVector< BasicBlock * > &BBs)
	Given BBs as input, find another set of BBs which collectively dominates BBs and have the minimal sum of frequencies.
static std::optional< APInt >	calculateOffsetDiff (const APInt &V1, const APInt &V2)
static bool	updateOperand (Instruction *Inst, unsigned Idx, Instruction *Mat)
	Updates the operand at Idx in instruction Inst with the result of instruction Mat.

Variables
static cl::opt< bool >	ConstHoistWithBlockFrequency ("consthoist-with-block-frequency", cl::init(true), cl::Hidden, cl::desc("Enable the use of the block frequency analysis to reduce the " "chance to execute const materialization more frequently than " "without hoisting."))
static cl::opt< bool >	ConstHoistGEP ("consthoist-gep", cl::init(false), cl::Hidden, cl::desc("Try hoisting constant gep expressions"))
static cl::opt< unsigned >	MinNumOfDependentToRebase ("consthoist-min-num-to-rebase", cl::desc("Do not rebase if number of dependent constants of a Base is less " "than this number."), cl::init(0), cl::Hidden)
	consthoist
Constant	Hoisting
Constant	false

Macro Definition Documentation

DEBUG_TYPE

#define DEBUG_TYPE   "consthoist"

Definition at line 76 of file ConstantHoisting.cpp.

Function Documentation

calculateOffsetDiff()

static std::optional< APInt > calculateOffsetDiff ( const APInt &  V1, const APInt &  V2  )

static

Definition at line 540 of file ConstantHoisting.cpp.

References llvm::APInt::getBitWidth(), and llvm::APInt::getLimitedValue().

findBestInsertionSet()

static void findBestInsertionSet ( DominatorTree &  DT, BlockFrequencyInfo &  BFI, BasicBlock *  Entry, SetVector< BasicBlock * > &  BBs  )

static

Given BBs as input, find another set of BBs which collectively dominates BBs and have the minimal sum of frequencies.

Return the BB set found in BBs.

Definition at line 216 of file ConstantHoisting.cpp.

References assert(), llvm::DomTreeNodeBase< NodeT >::children(), llvm::SetVector< T, Vector, Set, N >::clear(), llvm::SetVector< T, Vector, Set, N >::count(), llvm::SmallPtrSetImpl< PtrType >::count(), llvm::DomTreeNodeBase< NodeT >::getBlock(), llvm::DomTreeNodeBase< NodeT >::getIDom(), llvm::DominatorTreeBase< NodeT, IsPostDom >::getNode(), Idx, llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::insert(), llvm::SetVector< T, Vector, Set, N >::insert(), llvm::SmallPtrSetImpl< PtrType >::insert(), isCandidate(), llvm::DominatorTree::isReachableFromEntry(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::reserve(), llvm::reverse(), and llvm::SmallVectorBase< Size_T >::size().

INITIALIZE_PASS_BEGIN()

INITIALIZE_PASS_BEGIN	(	ConstantHoistingLegacyPass	,
		"consthoist"	,
		"Constant Hoisting"	,
		false	,
		false
	)

STATISTIC() [1/2]

STATISTIC	(	NumConstantsHoisted	,
		"Number of constants hoisted"
	)

STATISTIC() [2/2]

STATISTIC	(	NumConstantsRebased	,
		"Number of constants rebased"
	)

updateOperand()

static bool updateOperand ( Instruction *  Inst, unsigned  Idx, Instruction *  Mat  )

static

Updates the operand at Idx in instruction Inst with the result of instruction Mat.

If the instruction is a PHI node then special handling for duplicate values from the same incoming basic block is required.

Returns

The update will always succeed, but the return value indicated if Mat was used for the update or not.

Definition at line 731 of file ConstantHoisting.cpp.

References Idx, PHI, and llvm::User::setOperand().

Variable Documentation

consthoist

consthoist

Definition at line 135 of file ConstantHoisting.cpp.

ConstHoistGEP

cl::opt< bool > ConstHoistGEP("consthoist-gep", cl::init(false), cl::Hidden, cl::desc("Try hoisting constant gep expressions")) ( "consthoist-gep"  , cl::init(false)  , cl::Hidden  , cl::desc("Try hoisting constant gep expressions")    )

static

ConstHoistWithBlockFrequency

cl::opt< bool > ConstHoistWithBlockFrequency("consthoist-with-block-frequency", cl::init(true), cl::Hidden, cl::desc("Enable the use of the block frequency analysis to reduce the " "chance to execute const materialization more frequently than " "without hoisting.")) ( "consthoist-with-block-frequency"  , cl::init(true)  , cl::Hidden  , cl::desc("Enable the use of the block frequency analysis to reduce the " "chance to execute const materialization more frequently than " "without hoisting.")    )

static

Referenced by llvm::ConstantHoistingPass::run().

false

Constant false

Definition at line 136 of file ConstantHoisting.cpp.

Hoisting

Constant Hoisting

Definition at line 136 of file ConstantHoisting.cpp.

MinNumOfDependentToRebase

cl::opt< unsigned > MinNumOfDependentToRebase("consthoist-min-num-to-rebase", cl::desc("Do not rebase if number of dependent constants of a Base is less " "than this number."), cl::init(0), cl::Hidden) ( "consthoist-min-num-to-rebase"  , cl::desc("Do not rebase if number of dependent constants of a Base is less " "than this number.")  , cl::init(0)  , cl::Hidden    )

static