LLVM  3.7.0
Macros | Functions | Variables
IfConversion.cpp File Reference
#include "llvm/CodeGen/Passes.h"
#include "BranchFolding.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/LivePhysRegs.h"
#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
#include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/TargetSchedule.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 dependency graph for IfConversion.cpp:

Go to the source code of this file.

Macros

#define DEBUG_TYPE   "ifcvt"
 

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 (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)
 findFalseBlock - BB has a fallthrough. More...
 
static MachineBasicBlockgetNextBlock (MachineBasicBlock *BB)
 getNextBlock - Returns the next block in the function blocks ordering. More...
 
static bool canFallThroughTo (MachineBasicBlock *BB, MachineBasicBlock *ToBB)
 canFallThroughTo - Returns true either if ToBB is the next block after BB or that all the intervening blocks are empty (given BB can fall through to its next block). More...
 
static void InsertUncondBranch (MachineBasicBlock *BB, MachineBasicBlock *ToBB, const TargetInstrInfo *TII)
 InsertUncondBranch - Inserts an unconditional branch from BB to ToBB. 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 not live/used by MI. More...
 
static void RemoveKills (MachineInstr &MI, const LivePhysRegs &DontKill)
 Remove kill flags from operands with a registers in the DontKill set. More...
 
static void RemoveKills (MachineBasicBlock::iterator I, MachineBasicBlock::iterator E, const LivePhysRegs &DontKill, const MCRegisterInfo &MCRI)
 Walks a range of machine instructions and removes kill flags for registers in the DontKill set. More...
 
static void ScaleWeights (uint64_t NewTrue, uint64_t NewFalse, MachineBasicBlock *MBB, const MachineBasicBlock *TrueBB, const MachineBasicBlock *FalseBB, const MachineBranchProbabilityInfo *MBPI)
 Scale down weights to fit into uint32_t. More...
 
static bool MaySpeculate (const MachineInstr *MI, SmallSet< unsigned, 4 > &LaterRedefs)
 

Variables

static cl::opt< intIfCvtFnStart ("ifcvt-fn-start", cl::init(-1), cl::Hidden)
 
static cl::opt< intIfCvtFnStop ("ifcvt-fn-stop", cl::init(-1), cl::Hidden)
 
static cl::opt< intIfCvtLimit ("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< boolIfCvtBranchFold ("ifcvt-branch-fold", cl::init(true), cl::Hidden)
 

Macro Definition Documentation

#define DEBUG_TYPE   "ifcvt"

Definition at line 38 of file IfConversion.cpp.

Function Documentation

static bool canFallThroughTo ( MachineBasicBlock BB,
MachineBasicBlock ToBB 
)
static

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

Definition at line 963 of file IfConversion.cpp.

References llvm::MachineFunction::end(), and llvm::MachineBasicBlock::getParent().

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

findFalseBlock - BB has a fallthrough.

Find its 'false' successor given its 'true' successor.

Definition at line 438 of file IfConversion.cpp.

References SI, llvm::MachineBasicBlock::succ_begin(), and llvm::MachineBasicBlock::succ_end().

static MachineBasicBlock* getNextBlock ( MachineBasicBlock BB)
inlinestatic

getNextBlock - Returns the next block in the function blocks ordering.

If it is the end, returns NULL.

Definition at line 464 of file IfConversion.cpp.

References llvm::MachineFunction::end(), llvm::MachineBasicBlock::getParent(), and I.

static void InsertUncondBranch ( MachineBasicBlock BB,
MachineBasicBlock ToBB,
const TargetInstrInfo TII 
)
static

InsertUncondBranch - Inserts an unconditional branch from BB to ToBB.

Definition at line 993 of file IfConversion.cpp.

References llvm::TargetInstrInfo::InsertBranch().

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

Remove kill flags from operands with a registers in the DontKill set.

Definition at line 1049 of file IfConversion.cpp.

References llvm::LivePhysRegs::contains(), and llvm::MachineOperandIteratorBase::isValid().

Referenced by RemoveKills().

static void RemoveKills ( MachineBasicBlock::iterator  I,
MachineBasicBlock::iterator  E,
const LivePhysRegs DontKill,
const MCRegisterInfo MCRI 
)
static

Walks a range of machine instructions and removes kill flags for registers in the DontKill set.

Definition at line 1062 of file IfConversion.cpp.

References I, and RemoveKills().

static void ScaleWeights ( uint64_t  NewTrue,
uint64_t  NewFalse,
MachineBasicBlock MBB,
const MachineBasicBlock TrueBB,
const MachineBasicBlock FalseBB,
const MachineBranchProbabilityInfo MBPI 
)
static

Scale down weights to fit into uint32_t.

NewTrue is the new weight for successor TrueBB, and NewFalse is the new weight for successor FalseBB.

Definition at line 1159 of file IfConversion.cpp.

References llvm::MachineBranchProbabilityInfo::getEdgeWeight(), llvm::MachineBasicBlock::setSuccWeight(), SI, llvm::MachineBasicBlock::succ_begin(), and llvm::MachineBasicBlock::succ_end().

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 ( NumIfConvBBs  ,
"Number of if-converted blocks"   
)
STATISTIC ( NumDupBBs  ,
"Number of duplicated blocks"   
)
STATISTIC ( NumUnpred  ,
"Number of true blocks of diamonds unpredicated"   
)
static void UpdatePredRedefs ( MachineInstr MI,
LivePhysRegs Redefs 
)
static

Variable Documentation

cl::opt<bool> DisableDiamond("disable-ifcvt-diamond", cl::init(false), cl::Hidden)
static
cl::opt<bool> DisableSimple("disable-ifcvt-simple", cl::init(false), cl::Hidden)
static
cl::opt<bool> DisableSimpleF("disable-ifcvt-simple-false", cl::init(false), cl::Hidden)
static
cl::opt<bool> DisableTriangle("disable-ifcvt-triangle", cl::init(false), cl::Hidden)
static
cl::opt<bool> DisableTriangleF("disable-ifcvt-triangle-false", cl::init(false), cl::Hidden)
static
cl::opt<bool> DisableTriangleFR("disable-ifcvt-triangle-false-rev", cl::init(false), cl::Hidden)
static
cl::opt<bool> DisableTriangleR("disable-ifcvt-triangle-rev", cl::init(false), cl::Hidden)
static
cl::opt<bool> IfCvtBranchFold("ifcvt-branch-fold", cl::init(true), cl::Hidden)
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