HardwareLoops.cpp File Reference

Insert hardware loop intrinsics into loops which are deemed profitable by the target, by querying TargetTransformInfo. More...

#include "llvm/CodeGen/HardwareLoops.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/BranchProbabilityInfo.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/OptimizationRemarkEmitter.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Value.h"
#include "llvm/InitializePasses.h"
#include "llvm/Pass.h"
#include "llvm/PassRegistry.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Transforms/Utils.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/LoopUtils.h"
#include "llvm/Transforms/Utils/ScalarEvolutionExpander.h"

Go to the source code of this file.

Macros
#define	DEBUG_TYPE   "hardware-loops"
#define	HW_LOOPS_NAME   "Hardware Loop Insertion"

Functions
	STATISTIC (NumHWLoops, "Number of loops converted to hardware loops")
static void	debugHWLoopFailure (const StringRef DebugMsg, Instruction *I)
static OptimizationRemarkAnalysis	createHWLoopAnalysis (StringRef RemarkName, Loop *L, Instruction *I)
static bool	CanGenerateTest (Loop *L, Value *Count)

Variables
static cl::opt< bool >	ForceHardwareLoops ("force-hardware-loops", cl::Hidden, cl::init(false), cl::desc("Force hardware loops intrinsics to be inserted"))
static cl::opt< bool >	ForceHardwareLoopPHI ("force-hardware-loop-phi", cl::Hidden, cl::init(false), cl::desc("Force hardware loop counter to be updated through a phi"))
static cl::opt< bool >	ForceNestedLoop ("force-nested-hardware-loop", cl::Hidden, cl::init(false), cl::desc("Force allowance of nested hardware loops"))
static cl::opt< unsigned >	LoopDecrement ("hardware-loop-decrement", cl::Hidden, cl::init(1), cl::desc("Set the loop decrement value"))
static cl::opt< unsigned >	CounterBitWidth ("hardware-loop-counter-bitwidth", cl::Hidden, cl::init(32), cl::desc("Set the loop counter bitwidth"))
static cl::opt< bool >	ForceGuardLoopEntry ("force-hardware-loop-guard", cl::Hidden, cl::init(false), cl::desc("Force generation of loop guard intrinsic"))

Detailed Description

Insert hardware loop intrinsics into loops which are deemed profitable by the target, by querying TargetTransformInfo.

A hardware loop comprises of two intrinsics: one, outside the loop, to set the loop iteration count and another, in the exit block, to decrement the counter. The decremented value can either be carried through the loop via a phi or handled in some opaque way by the target.

Definition in file HardwareLoops.cpp.

Macro Definition Documentation

DEBUG_TYPE

#define DEBUG_TYPE   "hardware-loops"

Definition at line 45 of file HardwareLoops.cpp.

HW_LOOPS_NAME

#define HW_LOOPS_NAME   "Hardware Loop Insertion"

Definition at line 47 of file HardwareLoops.cpp.

Function Documentation

CanGenerateTest()

static bool CanGenerateTest ( Loop *  L, Value *  Count  )

static

Definition at line 400 of file HardwareLoops.cpp.

References llvm::dbgs(), llvm::User::getOperand(), llvm::CmpInst::getPredicate(), llvm::BasicBlock::getSinglePredecessor(), llvm::BasicBlock::getTerminator(), llvm::CmpInst::ICMP_NE, and LLVM_DEBUG.

createHWLoopAnalysis()

static OptimizationRemarkAnalysis createHWLoopAnalysis ( StringRef  RemarkName, Loop *  L, Instruction *  I  )

static

Definition at line 92 of file HardwareLoops.cpp.

References DEBUG_TYPE, DL, and I.

debugHWLoopFailure()

static void debugHWLoopFailure ( const StringRef  DebugMsg, Instruction *  I  )

static

Definition at line 80 of file HardwareLoops.cpp.

References llvm::dbgs(), and I.

STATISTIC()

STATISTIC	(	NumHWLoops	,
		"Number of loops converted to hardware loops"
	)

Variable Documentation

CounterBitWidth

cl::opt< unsigned > CounterBitWidth("hardware-loop-counter-bitwidth", cl::Hidden, cl::init(32), cl::desc("Set the loop counter bitwidth")) ( "hardware-loop-counter-bitwidth"  , cl::Hidden  , cl::init(32)  , cl::desc("Set the loop counter bitwidth")    )

static

ForceGuardLoopEntry

cl::opt< bool > ForceGuardLoopEntry("force-hardware-loop-guard", cl::Hidden, cl::init(false), cl::desc("Force generation of loop guard intrinsic")) ( "force-hardware-loop-guard"  , cl::Hidden  , cl::init(false)  , cl::desc("Force generation of loop guard intrinsic")    )

static

ForceHardwareLoopPHI

cl::opt< bool > ForceHardwareLoopPHI("force-hardware-loop-phi", cl::Hidden, cl::init(false), cl::desc("Force hardware loop counter to be updated through a phi")) ( "force-hardware-loop-phi"  , cl::Hidden  , cl::init(false)  , cl::desc("Force hardware loop counter to be updated through a phi")    )

static

Referenced by llvm::HardwareLoopInfo::isHardwareLoopCandidate().

ForceHardwareLoops

cl::opt< bool > ForceHardwareLoops("force-hardware-loops", cl::Hidden, cl::init(false), cl::desc("Force hardware loops intrinsics to be inserted")) ( "force-hardware-loops"  , cl::Hidden  , cl::init(false)  , cl::desc("Force hardware loops intrinsics to be inserted")    )

static

ForceNestedLoop

cl::opt< bool > ForceNestedLoop("force-nested-hardware-loop", cl::Hidden, cl::init(false), cl::desc("Force allowance of nested hardware loops")) ( "force-nested-hardware-loop"  , cl::Hidden  , cl::init(false)  , cl::desc("Force allowance of nested hardware loops")    )

static

Referenced by llvm::HardwareLoopInfo::isHardwareLoopCandidate().

LoopDecrement

cl::opt< unsigned > LoopDecrement("hardware-loop-decrement", cl::Hidden, cl::init(1), cl::desc("Set the loop decrement value")) ( "hardware-loop-decrement"  , cl::Hidden  , cl::init(1)  , cl::desc("Set the loop decrement value")    )

static