SimplifyCFGPass.cpp File Reference

#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/CFG.h"
#include "llvm/Analysis/DomTreeUpdater.h"
#include "llvm/Analysis/GlobalsModRef.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/DebugInfoMetadata.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/InitializePasses.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Scalar/SimplifyCFG.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/SimplifyCFGOptions.h"
#include <utility>

Go to the source code of this file.

Macros
#define	DEBUG_TYPE   "simplifycfg"

Functions
	STATISTIC (NumSimpl, "Number of blocks simplified")
static bool	performBlockTailMerging (Function &F, ArrayRef< BasicBlock * > BBs, std::vector< DominatorTree::UpdateType > *Updates)
static bool	tailMergeBlocksWithSimilarFunctionTerminators (Function &F, DomTreeUpdater *DTU)
static bool	iterativelySimplifyCFG (Function &F, const TargetTransformInfo &TTI, DomTreeUpdater *DTU, const SimplifyCFGOptions &Options)
	Call SimplifyCFG on all the blocks in the function, iterating until no more changes are made.
static bool	simplifyFunctionCFGImpl (Function &F, const TargetTransformInfo &TTI, DominatorTree *DT, const SimplifyCFGOptions &Options)
static bool	simplifyFunctionCFG (Function &F, const TargetTransformInfo &TTI, DominatorTree *DT, const SimplifyCFGOptions &Options)
static void	applyCommandLineOverridesToOptions (SimplifyCFGOptions &Options)
	INITIALIZE_PASS_BEGIN (CFGSimplifyPass, "simplifycfg", "Simplify the CFG", false, false) INITIALIZE_PASS_END(CFGSimplifyPass

Variables
static cl::opt< unsigned >	UserBonusInstThreshold ("bonus-inst-threshold", cl::Hidden, cl::init(1), cl::desc("Control the number of bonus instructions (default = 1)"))
static cl::opt< bool >	UserKeepLoops ("keep-loops", cl::Hidden, cl::init(true), cl::desc("Preserve canonical loop structure (default = true)"))
static cl::opt< bool >	UserSwitchRangeToICmp ("switch-range-to-icmp", cl::Hidden, cl::init(false), cl::desc("Convert switches into an integer range comparison (default = false)"))
static cl::opt< bool >	UserSwitchToLookup ("switch-to-lookup", cl::Hidden, cl::init(false), cl::desc("Convert switches to lookup tables (default = false)"))
static cl::opt< bool >	UserForwardSwitchCond ("forward-switch-cond", cl::Hidden, cl::init(false), cl::desc("Forward switch condition to phi ops (default = false)"))
static cl::opt< bool >	UserHoistCommonInsts ("hoist-common-insts", cl::Hidden, cl::init(false), cl::desc("hoist common instructions (default = false)"))
static cl::opt< bool >	UserSinkCommonInsts ("sink-common-insts", cl::Hidden, cl::init(false), cl::desc("Sink common instructions (default = false)"))
static cl::opt< bool >	UserSpeculateUnpredictables ("speculate-unpredictables", cl::Hidden, cl::init(false), cl::desc("Speculate unpredictable branches (default = false)"))
	simplifycfg
Simplify the	CFG
Simplify the	false

Macro Definition Documentation

DEBUG_TYPE

#define DEBUG_TYPE   "simplifycfg"

Definition at line 49 of file SimplifyCFGPass.cpp.

Function Documentation

applyCommandLineOverridesToOptions()

static void applyCommandLineOverridesToOptions ( SimplifyCFGOptions &  Options )

static

Definition at line 316 of file SimplifyCFGPass.cpp.

References Options, UserBonusInstThreshold, UserForwardSwitchCond, UserHoistCommonInsts, UserKeepLoops, UserSinkCommonInsts, UserSpeculateUnpredictables, UserSwitchRangeToICmp, and UserSwitchToLookup.

Referenced by llvm::SimplifyCFGPass::SimplifyCFGPass().

INITIALIZE_PASS_BEGIN()

INITIALIZE_PASS_BEGIN	(	CFGSimplifyPass	,
		"simplifycfg"	,
		"Simplify the CFG"	,
		false	,
		false
	)

iterativelySimplifyCFG()

static bool iterativelySimplifyCFG ( Function &  F, const TargetTransformInfo &  TTI, DomTreeUpdater *  DTU, const SimplifyCFGOptions &  Options  )

static

Call SimplifyCFG on all the blocks in the function, iterating until no more changes are made.

Definition at line 227 of file SimplifyCFGPass.cpp.

References assert(), llvm::SmallPtrSetImpl< PtrType >::begin(), llvm::SmallPtrSetImpl< PtrType >::end(), F, llvm::FindFunctionBackedges(), llvm::SmallPtrSetImpl< PtrType >::insert(), llvm::GenericDomTreeUpdater< DerivedT, DomTreeT, PostDomTreeT >::isBBPendingDeletion(), Options, and llvm::simplifyCFG().

Referenced by simplifyFunctionCFGImpl().

performBlockTailMerging()

static bool performBlockTailMerging ( Function &  F, ArrayRef< BasicBlock * >  BBs, std::vector< DominatorTree::UpdateType > *  Updates  )

static

Definition at line 87 of file SimplifyCFGPass.cpp.

References assert(), llvm::BranchInst::Create(), llvm::BasicBlock::Create(), llvm::PHINode::Create(), llvm::BasicBlock::end(), F, llvm::DILocation::getMergedLocation(), llvm::Value::getName(), llvm::Instruction::getOpcode(), getType(), I, llvm::Instruction::insertInto(), llvm::User::operands(), llvm::SmallVectorImpl< T >::reserve(), llvm::SmallVectorImpl< T >::resize(), llvm::Instruction::setDebugLoc(), llvm::ArrayRef< T >::size(), and llvm::zip().

Referenced by tailMergeBlocksWithSimilarFunctionTerminators().

simplifyFunctionCFG()

static bool simplifyFunctionCFG ( Function &  F, const TargetTransformInfo &  TTI, DominatorTree *  DT, const SimplifyCFGOptions &  Options  )

static

Definition at line 299 of file SimplifyCFGPass.cpp.

References assert(), F, Options, llvm::RequireAndPreserveDomTree, simplifyFunctionCFGImpl(), and llvm::DominatorTreeBase< NodeT, IsPostDom >::verify().

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

simplifyFunctionCFGImpl()

static bool simplifyFunctionCFGImpl ( Function &  F, const TargetTransformInfo &  TTI, DominatorTree *  DT, const SimplifyCFGOptions &  Options  )

static

Definition at line 270 of file SimplifyCFGPass.cpp.

References F, iterativelySimplifyCFG(), Options, llvm::removeUnreachableBlocks(), and tailMergeBlocksWithSimilarFunctionTerminators().

Referenced by simplifyFunctionCFG().

STATISTIC()

STATISTIC	(	NumSimpl	,
		"Number of blocks simplified"
	)

tailMergeBlocksWithSimilarFunctionTerminators()

static bool tailMergeBlocksWithSimilarFunctionTerminators ( Function &  F, DomTreeUpdater *  DTU  )

static

Definition at line 161 of file SimplifyCFGPass.cpp.

References llvm::any_of(), llvm::GenericDomTreeUpdater< DerivedT, DomTreeT, PostDomTreeT >::applyUpdates(), F, llvm::GenericDomTreeUpdater< DerivedT, DomTreeT, PostDomTreeT >::isBBPendingDeletion(), llvm::make_second_range(), performBlockTailMerging(), and llvm::succ_empty().

Referenced by simplifyFunctionCFGImpl().

Variable Documentation

CFG

Simplify the CFG

Definition at line 426 of file SimplifyCFGPass.cpp.

false

Simplify the false

Definition at line 426 of file SimplifyCFGPass.cpp.

simplifycfg

simplifycfg

Definition at line 426 of file SimplifyCFGPass.cpp.

UserBonusInstThreshold

cl::opt< unsigned > UserBonusInstThreshold("bonus-inst-threshold", cl::Hidden, cl::init(1), cl::desc("Control the number of bonus instructions (default = 1)")) ( "bonus-inst-threshold"  , cl::Hidden  , cl::init(1)  , cl::desc("Control the number of bonus instructions (default = 1)")    )

static

Referenced by applyCommandLineOverridesToOptions().

UserForwardSwitchCond

cl::opt< bool > UserForwardSwitchCond("forward-switch-cond", cl::Hidden, cl::init(false), cl::desc("Forward switch condition to phi ops (default = false)")) ( "forward-switch-cond"  , cl::Hidden  , cl::init(false)  , cl::desc("Forward switch condition to phi ops (default = false)")    )

static

Referenced by applyCommandLineOverridesToOptions().

UserHoistCommonInsts

cl::opt< bool > UserHoistCommonInsts("hoist-common-insts", cl::Hidden, cl::init(false), cl::desc("hoist common instructions (default = false)")) ( "hoist-common-insts"  , cl::Hidden  , cl::init(false)  , cl::desc("hoist common instructions (default = false)")    )

static

Referenced by applyCommandLineOverridesToOptions().

UserKeepLoops

cl::opt< bool > UserKeepLoops("keep-loops", cl::Hidden, cl::init(true), cl::desc("Preserve canonical loop structure (default = true)")) ( "keep-loops"  , cl::Hidden  , cl::init(true)  , cl::desc("Preserve canonical loop structure (default = true)")    )

static

Referenced by applyCommandLineOverridesToOptions().

UserSinkCommonInsts

cl::opt< bool > UserSinkCommonInsts("sink-common-insts", cl::Hidden, cl::init(false), cl::desc("Sink common instructions (default = false)")) ( "sink-common-insts"  , cl::Hidden  , cl::init(false)  , cl::desc("Sink common instructions (default = false)")    )

static

Referenced by applyCommandLineOverridesToOptions().

UserSpeculateUnpredictables

cl::opt< bool > UserSpeculateUnpredictables("speculate-unpredictables", cl::Hidden, cl::init(false), cl::desc("Speculate unpredictable branches (default = false)")) ( "speculate-unpredictables"  , cl::Hidden  , cl::init(false)  , cl::desc("Speculate unpredictable branches (default = false)")    )

static

Referenced by applyCommandLineOverridesToOptions().

UserSwitchRangeToICmp

cl::opt< bool > UserSwitchRangeToICmp("switch-range-to-icmp", cl::Hidden, cl::init(false), cl::desc( "Convert switches into an integer range comparison (default = false)")) ( "switch-range-to-icmp"  , cl::Hidden  , cl::init(false)  , cl::desc( "Convert switches into an integer range comparison (default = false)")    )

static

Referenced by applyCommandLineOverridesToOptions().

UserSwitchToLookup

cl::opt< bool > UserSwitchToLookup("switch-to-lookup", cl::Hidden, cl::init(false), cl::desc("Convert switches to lookup tables (default = false)")) ( "switch-to-lookup"  , cl::Hidden  , cl::init(false)  , cl::desc("Convert switches to lookup tables (default = false)")    )

static

Referenced by applyCommandLineOverridesToOptions().