LLVM  6.0.0svn
Macros | Functions | Variables
IfConversion.cpp File Reference
#include "BranchFolding.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/ScopeExit.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/SparseSet.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/iterator_range.h"
#include "llvm/CodeGen/LivePhysRegs.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
#include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineOperand.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/TargetSchedule.h"
#include "llvm/IR/DebugLoc.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/Pass.h"
#include "llvm/Support/BranchProbability.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Target/TargetSubtargetInfo.h"
#include <algorithm>
#include <cassert>
#include <functional>
#include <iterator>
#include <memory>
#include <utility>
#include <vector>
Include dependency graph for IfConversion.cpp:

Go to the source code of this file.

Macros

#define DEBUG_TYPE   "if-converter"
 

Functions

 STATISTIC (NumSimple, "Number of simple if-conversions performed")
 
 STATISTIC (NumSimpleFalse, "Number of simple (F) if-conversions performed")
 
 STATISTIC (NumTriangle, "Number of triangle if-conversions performed")
 
 STATISTIC (NumTriangleRev, "Number of triangle (R) if-conversions performed")
 
 STATISTIC (NumTriangleFalse,"Number of triangle (F) if-conversions performed")
 
 STATISTIC (NumTriangleFRev, "Number of triangle (F/R) if-conversions performed")
 
 STATISTIC (NumDiamonds, "Number of diamond if-conversions performed")
 
 STATISTIC (NumForkedDiamonds, "Number of forked-diamond if-conversions performed")
 
 STATISTIC (NumIfConvBBs, "Number of if-converted blocks")
 
 STATISTIC (NumDupBBs, "Number of duplicated blocks")
 
 STATISTIC (NumUnpred, "Number of true blocks of diamonds unpredicated")
 
static MachineBasicBlockfindFalseBlock (MachineBasicBlock *BB, MachineBasicBlock *TrueBB)
 BB has a fallthrough. Find its 'false' successor given its 'true' successor. More...
 
static MachineBasicBlockgetNextBlock (MachineBasicBlock &MBB)
 Returns the next block in the function blocks ordering. More...
 
static void verifySameBranchInstructions (MachineBasicBlock *MBB1, MachineBasicBlock *MBB2)
 
static bool canFallThroughTo (MachineBasicBlock &MBB, MachineBasicBlock &ToMBB)
 Returns true either if ToMBB is the next block after MBB or that all the intervening blocks are empty (given MBB can fall through to its next block). More...
 
static void InsertUncondBranch (MachineBasicBlock &MBB, MachineBasicBlock &ToMBB, const TargetInstrInfo *TII)
 Inserts an unconditional branch from MBB to ToMBB. More...
 
static void UpdatePredRedefs (MachineInstr &MI, LivePhysRegs &Redefs)
 Behaves like LiveRegUnits::StepForward() but also adds implicit uses to all values defined in MI which are also live/used by MI. More...
 
static bool MaySpeculate (const MachineInstr &MI, SmallSet< unsigned, 4 > &LaterRedefs)
 

Variables

static cl::opt< int > IfCvtFnStart ("ifcvt-fn-start", cl::init(-1), cl::Hidden)
 
static cl::opt< int > IfCvtFnStop ("ifcvt-fn-stop", cl::init(-1), cl::Hidden)
 
static cl::opt< int > IfCvtLimit ("ifcvt-limit", cl::init(-1), cl::Hidden)
 
static cl::opt< boolDisableSimple ("disable-ifcvt-simple", cl::init(false), cl::Hidden)
 
static cl::opt< boolDisableSimpleF ("disable-ifcvt-simple-false", cl::init(false), cl::Hidden)
 
static cl::opt< boolDisableTriangle ("disable-ifcvt-triangle", cl::init(false), cl::Hidden)
 
static cl::opt< boolDisableTriangleR ("disable-ifcvt-triangle-rev", cl::init(false), cl::Hidden)
 
static cl::opt< boolDisableTriangleF ("disable-ifcvt-triangle-false", cl::init(false), cl::Hidden)
 
static cl::opt< boolDisableTriangleFR ("disable-ifcvt-triangle-false-rev", cl::init(false), cl::Hidden)
 
static cl::opt< boolDisableDiamond ("disable-ifcvt-diamond", cl::init(false), cl::Hidden)
 
static cl::opt< boolDisableForkedDiamond ("disable-ifcvt-forked-diamond", cl::init(false), cl::Hidden)
 
static cl::opt< boolIfCvtBranchFold ("ifcvt-branch-fold", cl::init(true), cl::Hidden)
 

Macro Definition Documentation

◆ DEBUG_TYPE

#define DEBUG_TYPE   "if-converter"

Definition at line 57 of file IfConversion.cpp.

Function Documentation

◆ canFallThroughTo()

static bool canFallThroughTo ( MachineBasicBlock MBB,
MachineBasicBlock ToMBB 
)
static

Returns true either if ToMBB is the next block after MBB or that all the intervening blocks are empty (given MBB can fall through to its next block).

Definition at line 1325 of file IfConversion.cpp.

References E, llvm::MachineFunction::end(), llvm::ilist_node_impl< OptionsT >::getIterator(), llvm::MachineBasicBlock::getParent(), I, and llvm::MachineBasicBlock::predecessors().

Referenced by UpdatePredRedefs().

◆ findFalseBlock()

static MachineBasicBlock* findFalseBlock ( MachineBasicBlock BB,
MachineBasicBlock TrueBB 
)
static

BB has a fallthrough. Find its 'false' successor given its 'true' successor.

Definition at line 509 of file IfConversion.cpp.

References llvm::TargetInstrInfo::insertBranch(), llvm::TargetInstrInfo::removeBranch(), llvm::TargetInstrInfo::reverseBranchCondition(), llvm::MachineBasicBlock::successors(), and std::swap().

Referenced by verifySameBranchInstructions().

◆ getNextBlock()

static MachineBasicBlock* getNextBlock ( MachineBasicBlock MBB)
inlinestatic

◆ InsertUncondBranch()

static void InsertUncondBranch ( MachineBasicBlock MBB,
MachineBasicBlock ToMBB,
const TargetInstrInfo TII 
)
static

Inserts an unconditional branch from MBB to ToMBB.

Definition at line 1354 of file IfConversion.cpp.

References llvm::TargetInstrInfo::insertBranch().

Referenced by UpdatePredRedefs().

◆ MaySpeculate()

static bool MaySpeculate ( const MachineInstr MI,
SmallSet< unsigned, 4 > &  LaterRedefs 
)
static

◆ STATISTIC() [1/11]

STATISTIC ( NumSimple  ,
"Number of simple if-conversions performed"   
)

◆ STATISTIC() [2/11]

STATISTIC ( NumSimpleFalse  ,
"Number of simple (F) if-conversions performed"   
)

◆ STATISTIC() [3/11]

STATISTIC ( NumTriangle  ,
"Number of triangle if-conversions performed"   
)

◆ STATISTIC() [4/11]

STATISTIC ( NumTriangleRev  ,
"Number of triangle (R) if-conversions performed"   
)

◆ STATISTIC() [5/11]

STATISTIC ( NumTriangleFalse  ,
"Number of triangle (F) if-conversions performed"   
)

◆ STATISTIC() [6/11]

STATISTIC ( NumTriangleFRev  ,
"Number of triangle (F/R) if-conversions performed"   
)

◆ STATISTIC() [7/11]

STATISTIC ( NumDiamonds  ,
"Number of diamond if-conversions performed"   
)

◆ STATISTIC() [8/11]

STATISTIC ( NumForkedDiamonds  ,
"Number of forked-diamond if-conversions performed"   
)

◆ STATISTIC() [9/11]

STATISTIC ( NumIfConvBBs  ,
"Number of if-converted blocks"   
)

◆ STATISTIC() [10/11]

STATISTIC ( NumDupBBs  ,
"Number of duplicated blocks"   
)

◆ STATISTIC() [11/11]

STATISTIC ( NumUnpred  ,
"Number of true blocks of diamonds unpredicated"   
)

◆ UpdatePredRedefs()

static void UpdatePredRedefs ( MachineInstr MI,
LivePhysRegs Redefs 
)
static

Behaves like LiveRegUnits::StepForward() but also adds implicit uses to all values defined in MI which are also live/used by MI.

Definition at line 1363 of file IfConversion.cpp.

References llvm::LivePhysRegs::addLiveIns(), llvm::MachineInstrBuilder::addReg(), assert(), llvm::MachineBasicBlock::begin(), canFallThroughTo(), llvm::SmallSet< T, N, C >::count(), llvm::SparseSet< ValueT, KeyFunctorT, SparseT >::count(), llvm::RegState::Define, llvm::NVPTXISD::Dummy, llvm::MachineBasicBlock::empty(), llvm::MachineBasicBlock::end(), llvm::MachineBasicBlock::erase(), llvm::find(), llvm::MachineBranchProbabilityInfo::getEdgeProbability(), llvm::MachineBasicBlock::getFirstNonDebugInstr(), llvm::MachineBasicBlock::getFirstTerminator(), llvm::MachineInstr::getMF(), getNextBlock(), llvm::MachineBasicBlock::getNumber(), llvm::MCRegisterInfo::getNumRegs(), llvm::BranchProbability::getOne(), llvm::MachineOperand::getParent(), llvm::TargetSubtargetInfo::getRegisterInfo(), llvm::MachineFunction::getSubtarget(), llvm::MachineBasicBlock::hasAddressTaken(), llvm::RegState::Implicit, llvm::LivePhysRegs::init(), llvm::SmallSet< T, N, C >::insert(), llvm::SparseSet< ValueT, KeyFunctorT, SparseT >::insert(), llvm::TargetInstrInfo::insertBranch(), InsertUncondBranch(), llvm::TargetInstrInfo::isPredicated(), llvm::TargetInstrInfo::isProfitableToUnpredicate(), llvm::MachineOperand::isRegMask(), llvm::MCRegisterInfo::DiffListIterator::isValid(), Kind, llvm_unreachable, llvm::make_range(), MI, llvm::MachineBasicBlock::pred_begin(), llvm::MachineBasicBlock::pred_size(), llvm::MachineBasicBlock::predecessors(), llvm::SmallVectorTemplateBase< T, isPodLike >::push_back(), llvm::TargetInstrInfo::removeBranch(), llvm::TargetInstrInfo::reverseBranchCondition(), llvm::SparseSet< ValueT, KeyFunctorT, SparseT >::setUniverse(), llvm::LivePhysRegs::stepForward(), std::swap(), llvm::MachineRegisterInfo::tracksLiveness(), and verifySameBranchInstructions().

Referenced by MaySpeculate().

◆ verifySameBranchInstructions()

static void verifySameBranchInstructions ( MachineBasicBlock MBB1,
MachineBasicBlock MBB2 
)
static

Variable Documentation

◆ DisableDiamond

cl::opt<bool> DisableDiamond("disable-ifcvt-diamond", cl::init(false), cl::Hidden)
static

◆ DisableForkedDiamond

cl::opt<bool> DisableForkedDiamond("disable-ifcvt-forked-diamond", cl::init(false), cl::Hidden)
static

◆ DisableSimple

cl::opt<bool> DisableSimple("disable-ifcvt-simple", cl::init(false), cl::Hidden)
static

◆ DisableSimpleF

cl::opt<bool> DisableSimpleF("disable-ifcvt-simple-false", cl::init(false), cl::Hidden)
static

◆ DisableTriangle

cl::opt<bool> DisableTriangle("disable-ifcvt-triangle", cl::init(false), cl::Hidden)
static

◆ DisableTriangleF

cl::opt<bool> DisableTriangleF("disable-ifcvt-triangle-false", cl::init(false), cl::Hidden)
static

◆ DisableTriangleFR

cl::opt<bool> DisableTriangleFR("disable-ifcvt-triangle-false-rev", cl::init(false), cl::Hidden)
static

◆ DisableTriangleR

cl::opt<bool> DisableTriangleR("disable-ifcvt-triangle-rev", cl::init(false), cl::Hidden)
static

◆ IfCvtBranchFold

cl::opt<bool> IfCvtBranchFold("ifcvt-branch-fold", cl::init(true), cl::Hidden)
static

◆ IfCvtFnStart

cl::opt<int> IfCvtFnStart("ifcvt-fn-start", cl::init(-1), cl::Hidden)
static

◆ IfCvtFnStop

cl::opt<int> IfCvtFnStop("ifcvt-fn-stop", cl::init(-1), cl::Hidden)
static

◆ IfCvtLimit

cl::opt<int> IfCvtLimit("ifcvt-limit", cl::init(-1), cl::Hidden)
static