[llvm] r187278 - SimplifyCFG: Use parallel-and and parallel-or mode to consolidate branch conditions
Tom Stellard
tom at stellard.net
Mon Jul 29 11:23:50 PDT 2013
Hi David,
What configure flags does that buildbot use?
Mei,
Are you able to look into this?
-Tom
On Mon, Jul 29, 2013 at 09:07:16AM -0700, David Dean wrote:
> I believe this change has caused a failure of one of the tests when the compiler is built with lto:
>
> http://lab.llvm.org:8013/builders/clang-x86_64-darwin11-Rlto/builds/589
>
> Can you take look?
>
> On 26 Jul 2013, at 5:01 PM, Tom Stellard <thomas.stellard at amd.com> wrote:
>
> > Author: tstellar
> > Date: Fri Jul 26 19:01:07 2013
> > New Revision: 187278
> >
> > URL: http://llvm.org/viewvc/llvm-project?rev=187278&view=rev
> > Log:
> > SimplifyCFG: Use parallel-and and parallel-or mode to consolidate branch conditions
> >
> > Merge consecutive if-regions if they contain identical statements.
> > Both transformations reduce number of branches. The transformation
> > is guarded by a target-hook, and is currently enabled only for +R600,
> > but the correctness has been tested on X86 target using a variety of
> > CPU benchmarks.
> >
> > Patch by: Mei Ye
> >
> > Added:
> > llvm/trunk/lib/Target/R600/AMDGPUTargetTransformInfo.cpp
> > Modified:
> > llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h
> > llvm/trunk/include/llvm/InitializePasses.h
> > llvm/trunk/include/llvm/Transforms/Scalar.h
> > llvm/trunk/include/llvm/Transforms/Utils/Local.h
> > llvm/trunk/lib/Analysis/TargetTransformInfo.cpp
> > llvm/trunk/lib/CodeGen/BasicTargetTransformInfo.cpp
> > llvm/trunk/lib/Target/R600/AMDGPU.h
> > llvm/trunk/lib/Target/R600/AMDGPUTargetMachine.cpp
> > llvm/trunk/lib/Target/R600/AMDGPUTargetMachine.h
> > llvm/trunk/lib/Target/R600/CMakeLists.txt
> > llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp
> > llvm/trunk/lib/Transforms/Scalar/Scalar.cpp
> > llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp
> > llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp
> > llvm/trunk/tools/lto/LTOCodeGenerator.cpp
> > llvm/trunk/tools/opt/opt.cpp
> >
> > Modified: llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h (original)
> > +++ llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h Fri Jul 26 19:01:07 2013
> > @@ -171,6 +171,12 @@ public:
> > /// comments for a detailed explanation of the cost values.
> > virtual unsigned getUserCost(const User *U) const;
> >
> > + /// \brief hasBranchDivergence - Return true if branch divergence exists.
> > + /// Branch divergence has a significantly negative impact on GPU performance
> > + /// when threads in the same wavefront take different paths due to conditional
> > + /// branches.
> > + virtual bool hasBranchDivergence() const;
> > +
> > /// \brief Test whether calls to a function lower to actual program function
> > /// calls.
> > ///
> >
> > Modified: llvm/trunk/include/llvm/InitializePasses.h
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/InitializePasses.h?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/include/llvm/InitializePasses.h (original)
> > +++ llvm/trunk/include/llvm/InitializePasses.h Fri Jul 26 19:01:07 2013
> > @@ -86,7 +86,8 @@ void initializeCallGraphViewerPass(PassR
> > void initializeCFGOnlyPrinterPass(PassRegistry&);
> > void initializeCFGOnlyViewerPass(PassRegistry&);
> > void initializeCFGPrinterPass(PassRegistry&);
> > -void initializeCFGSimplifyPassPass(PassRegistry&);
> > +void initializeCFGOptimizePass(PassRegistry&);
> > +void initializeCFGCanonicalizePass(PassRegistry&);
> > void initializeStructurizeCFGPass(PassRegistry&);
> > void initializeCFGViewerPass(PassRegistry&);
> > void initializeCalculateSpillWeightsPass(PassRegistry&);
> >
> > Modified: llvm/trunk/include/llvm/Transforms/Scalar.h
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Scalar.h?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/include/llvm/Transforms/Scalar.h (original)
> > +++ llvm/trunk/include/llvm/Transforms/Scalar.h Fri Jul 26 19:01:07 2013
> > @@ -196,7 +196,7 @@ FunctionPass *createJumpThreadingPass();
> > // CFGSimplification - Merge basic blocks, eliminate unreachable blocks,
> > // simplify terminator instructions, etc...
> > //
> > -FunctionPass *createCFGSimplificationPass();
> > +FunctionPass *createCFGSimplificationPass(bool IsTargetAware = false);
> >
> > //===----------------------------------------------------------------------===//
> > //
> >
> > Modified: llvm/trunk/include/llvm/Transforms/Utils/Local.h
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Utils/Local.h?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/include/llvm/Transforms/Utils/Local.h (original)
> > +++ llvm/trunk/include/llvm/Transforms/Utils/Local.h Fri Jul 26 19:01:07 2013
> > @@ -39,6 +39,7 @@ class DataLayout;
> > class TargetLibraryInfo;
> > class TargetTransformInfo;
> > class DIBuilder;
> > +class AliasAnalysis;
> >
> > template<typename T> class SmallVectorImpl;
> >
> > @@ -136,7 +137,7 @@ bool EliminateDuplicatePHINodes(BasicBlo
> > /// the basic block that was pointed to.
> > ///
> > bool SimplifyCFG(BasicBlock *BB, const TargetTransformInfo &TTI,
> > - const DataLayout *TD = 0);
> > + const DataLayout *TD = 0, AliasAnalysis *AA = 0);
> >
> > /// FoldBranchToCommonDest - If this basic block is ONLY a setcc and a branch,
> > /// and if a predecessor branches to us and one of our successors, fold the
> >
> > Modified: llvm/trunk/lib/Analysis/TargetTransformInfo.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/TargetTransformInfo.cpp?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/Analysis/TargetTransformInfo.cpp (original)
> > +++ llvm/trunk/lib/Analysis/TargetTransformInfo.cpp Fri Jul 26 19:01:07 2013
> > @@ -88,6 +88,10 @@ unsigned TargetTransformInfo::getUserCos
> > return PrevTTI->getUserCost(U);
> > }
> >
> > +bool TargetTransformInfo::hasBranchDivergence() const {
> > + return PrevTTI->hasBranchDivergence();
> > +}
> > +
> > bool TargetTransformInfo::isLoweredToCall(const Function *F) const {
> > return PrevTTI->isLoweredToCall(F);
> > }
> > @@ -420,6 +424,8 @@ struct NoTTI : ImmutablePass, TargetTran
> > U->getOperand(0)->getType() : 0);
> > }
> >
> > + bool hasBranchDivergence() const { return false; }
> > +
> > bool isLoweredToCall(const Function *F) const {
> > // FIXME: These should almost certainly not be handled here, and instead
> > // handled with the help of TLI or the target itself. This was largely
> >
> > Modified: llvm/trunk/lib/CodeGen/BasicTargetTransformInfo.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/BasicTargetTransformInfo.cpp?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/CodeGen/BasicTargetTransformInfo.cpp (original)
> > +++ llvm/trunk/lib/CodeGen/BasicTargetTransformInfo.cpp Fri Jul 26 19:01:07 2013
> > @@ -65,6 +65,8 @@ public:
> > return this;
> > }
> >
> > + virtual bool hasBranchDivergence() const;
> > +
> > /// \name Scalar TTI Implementations
> > /// @{
> >
> > @@ -124,6 +126,7 @@ llvm::createBasicTargetTransformInfoPass
> > return new BasicTTI(TM);
> > }
> >
> > +bool BasicTTI::hasBranchDivergence() const { return false; }
> >
> > bool BasicTTI::isLegalAddImmediate(int64_t imm) const {
> > return getTLI()->isLegalAddImmediate(imm);
> >
> > Modified: llvm/trunk/lib/Target/R600/AMDGPU.h
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/R600/AMDGPU.h?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/Target/R600/AMDGPU.h (original)
> > +++ llvm/trunk/lib/Target/R600/AMDGPU.h Fri Jul 26 19:01:07 2013
> > @@ -45,6 +45,10 @@ FunctionPass *createAMDGPUConvertToISAPa
> > FunctionPass *createAMDGPUIndirectAddressingPass(TargetMachine &tm);
> > FunctionPass *createAMDGPUISelDag(TargetMachine &tm);
> >
> > +/// \brief Creates an AMDGPU-specific Target Transformation Info pass.
> > +ImmutablePass *
> > +createAMDGPUTargetTransformInfoPass(const AMDGPUTargetMachine *TM);
> > +
> > extern Target TheAMDGPUTarget;
> >
> > } // End namespace llvm
> >
> > Modified: llvm/trunk/lib/Target/R600/AMDGPUTargetMachine.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/R600/AMDGPUTargetMachine.cpp?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/Target/R600/AMDGPUTargetMachine.cpp (original)
> > +++ llvm/trunk/lib/Target/R600/AMDGPUTargetMachine.cpp Fri Jul 26 19:01:07 2013
> > @@ -105,6 +105,18 @@ TargetPassConfig *AMDGPUTargetMachine::c
> > return new AMDGPUPassConfig(this, PM);
> > }
> >
> > +//===----------------------------------------------------------------------===//
> > +// AMDGPU Analysis Pass Setup
> > +//===----------------------------------------------------------------------===//
> > +
> > +void AMDGPUTargetMachine::addAnalysisPasses(PassManagerBase &PM) {
> > + // Add first the target-independent BasicTTI pass, then our AMDGPU pass. This
> > + // allows the AMDGPU pass to delegate to the target independent layer when
> > + // appropriate.
> > + PM.add(createBasicTargetTransformInfoPass(this));
> > + PM.add(createAMDGPUTargetTransformInfoPass(this));
> > +}
> > +
> > bool
> > AMDGPUPassConfig::addPreISel() {
> > const AMDGPUSubtarget &ST = TM->getSubtarget<AMDGPUSubtarget>();
> >
> > Modified: llvm/trunk/lib/Target/R600/AMDGPUTargetMachine.h
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/R600/AMDGPUTargetMachine.h?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/Target/R600/AMDGPUTargetMachine.h (original)
> > +++ llvm/trunk/lib/Target/R600/AMDGPUTargetMachine.h Fri Jul 26 19:01:07 2013
> > @@ -61,6 +61,9 @@ public:
> > }
> > virtual const DataLayout *getDataLayout() const { return &Layout; }
> > virtual TargetPassConfig *createPassConfig(PassManagerBase &PM);
> > +
> > + /// \brief Register R600 analysis passes with a pass manager.
> > + virtual void addAnalysisPasses(PassManagerBase &PM);
> > };
> >
> > } // End namespace llvm
> >
> > Added: llvm/trunk/lib/Target/R600/AMDGPUTargetTransformInfo.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/R600/AMDGPUTargetTransformInfo.cpp?rev=187278&view=auto
> > ==============================================================================
> > --- llvm/trunk/lib/Target/R600/AMDGPUTargetTransformInfo.cpp (added)
> > +++ llvm/trunk/lib/Target/R600/AMDGPUTargetTransformInfo.cpp Fri Jul 26 19:01:07 2013
> > @@ -0,0 +1,90 @@
> > +//===-- AMDGPUTargetTransformInfo.cpp - AMDGPU specific TTI pass ---------===//
> > +//
> > +// The LLVM Compiler Infrastructure
> > +//
> > +// This file is distributed under the University of Illinois Open Source
> > +// License. See LICENSE.TXT for details.
> > +//
> > +//===----------------------------------------------------------------------===//
> > +//
> > +// \file
> > +// This file implements a TargetTransformInfo analysis pass specific to the
> > +// AMDGPU target machine. It uses the target's detailed information to provide
> > +// more precise answers to certain TTI queries, while letting the target
> > +// independent and default TTI implementations handle the rest.
> > +//
> > +//===----------------------------------------------------------------------===//
> > +
> > +#define DEBUG_TYPE "AMDGPUtti"
> > +#include "AMDGPU.h"
> > +#include "AMDGPUTargetMachine.h"
> > +#include "llvm/Analysis/TargetTransformInfo.h"
> > +#include "llvm/Support/Debug.h"
> > +#include "llvm/Target/TargetLowering.h"
> > +#include "llvm/Target/CostTable.h"
> > +using namespace llvm;
> > +
> > +// Declare the pass initialization routine locally as target-specific passes
> > +// don't have a target-wide initialization entry point, and so we rely on the
> > +// pass constructor initialization.
> > +namespace llvm {
> > +void initializeAMDGPUTTIPass(PassRegistry &);
> > +}
> > +
> > +namespace {
> > +
> > +class AMDGPUTTI : public ImmutablePass, public TargetTransformInfo {
> > + const AMDGPUTargetMachine *TM;
> > + const AMDGPUSubtarget *ST;
> > + const AMDGPUTargetLowering *TLI;
> > +
> > + /// Estimate the overhead of scalarizing an instruction. Insert and Extract
> > + /// are set if the result needs to be inserted and/or extracted from vectors.
> > + unsigned getScalarizationOverhead(Type *Ty, bool Insert, bool Extract) const;
> > +
> > +public:
> > + AMDGPUTTI() : ImmutablePass(ID), TM(0), ST(0), TLI(0) {
> > + llvm_unreachable("This pass cannot be directly constructed");
> > + }
> > +
> > + AMDGPUTTI(const AMDGPUTargetMachine *TM)
> > + : ImmutablePass(ID), TM(TM), ST(TM->getSubtargetImpl()),
> > + TLI(TM->getTargetLowering()) {
> > + initializeAMDGPUTTIPass(*PassRegistry::getPassRegistry());
> > + }
> > +
> > + virtual void initializePass() { pushTTIStack(this); }
> > +
> > + virtual void finalizePass() { popTTIStack(); }
> > +
> > + virtual void getAnalysisUsage(AnalysisUsage &AU) const {
> > + TargetTransformInfo::getAnalysisUsage(AU);
> > + }
> > +
> > + /// Pass identification.
> > + static char ID;
> > +
> > + /// Provide necessary pointer adjustments for the two base classes.
> > + virtual void *getAdjustedAnalysisPointer(const void *ID) {
> > + if (ID == &TargetTransformInfo::ID)
> > + return (TargetTransformInfo *)this;
> > + return this;
> > + }
> > +
> > + virtual bool hasBranchDivergence() const;
> > +
> > + /// @}
> > +};
> > +
> > +} // end anonymous namespace
> > +
> > +INITIALIZE_AG_PASS(AMDGPUTTI, TargetTransformInfo, "AMDGPUtti",
> > + "AMDGPU Target Transform Info", true, true, false)
> > +char AMDGPUTTI::ID = 0;
> > +
> > +ImmutablePass *
> > +llvm::createAMDGPUTargetTransformInfoPass(const AMDGPUTargetMachine *TM) {
> > + return new AMDGPUTTI(TM);
> > +}
> > +
> > +bool AMDGPUTTI::hasBranchDivergence() const { return true; }
> >
> > Modified: llvm/trunk/lib/Target/R600/CMakeLists.txt
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/R600/CMakeLists.txt?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/Target/R600/CMakeLists.txt (original)
> > +++ llvm/trunk/lib/Target/R600/CMakeLists.txt Fri Jul 26 19:01:07 2013
> > @@ -23,6 +23,7 @@ add_llvm_target(R600CodeGen
> > AMDGPUMachineFunction.cpp
> > AMDGPUSubtarget.cpp
> > AMDGPUTargetMachine.cpp
> > + AMDGPUTargetTransformInfo.cpp
> > AMDGPUISelLowering.cpp
> > AMDGPUConvertToISA.cpp
> > AMDGPUInstrInfo.cpp
> >
> > Modified: llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp (original)
> > +++ llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp Fri Jul 26 19:01:07 2013
> > @@ -235,7 +235,7 @@ void PassManagerBuilder::populateModuleP
> > }
> >
> > MPM.add(createAggressiveDCEPass()); // Delete dead instructions
> > - MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
> > + MPM.add(createCFGSimplificationPass(true)); // Merge & remove BBs
> > MPM.add(createInstructionCombiningPass()); // Clean up after everything.
> >
> > // As an experimental mode, run any vectorization passes in a separate
> > @@ -371,7 +371,7 @@ void PassManagerBuilder::populateLTOPass
> > PM.add(createJumpThreadingPass());
> >
> > // Delete basic blocks, which optimization passes may have killed.
> > - PM.add(createCFGSimplificationPass());
> > + PM.add(createCFGSimplificationPass(true));
> >
> > // Now that we have optimized the program, discard unreachable functions.
> > PM.add(createGlobalDCEPass());
> >
> > Modified: llvm/trunk/lib/Transforms/Scalar/Scalar.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/Scalar.cpp?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/Transforms/Scalar/Scalar.cpp (original)
> > +++ llvm/trunk/lib/Transforms/Scalar/Scalar.cpp Fri Jul 26 19:01:07 2013
> > @@ -57,7 +57,8 @@ void llvm::initializeScalarOpts(PassRegi
> > initializeSROAPass(Registry);
> > initializeSROA_DTPass(Registry);
> > initializeSROA_SSAUpPass(Registry);
> > - initializeCFGSimplifyPassPass(Registry);
> > + initializeCFGCanonicalizePass(Registry);
> > + initializeCFGOptimizePass(Registry);
> > initializeStructurizeCFGPass(Registry);
> > initializeSinkingPass(Registry);
> > initializeTailCallElimPass(Registry);
> >
> > Modified: llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp (original)
> > +++ llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp Fri Jul 26 19:01:07 2013
> > @@ -27,6 +27,7 @@
> > #include "llvm/ADT/SmallVector.h"
> > #include "llvm/ADT/Statistic.h"
> > #include "llvm/Analysis/TargetTransformInfo.h"
> > +#include "llvm/Analysis/AliasAnalysis.h"
> > #include "llvm/IR/Attributes.h"
> > #include "llvm/IR/Constants.h"
> > #include "llvm/IR/DataLayout.h"
> > @@ -41,30 +42,62 @@ using namespace llvm;
> > STATISTIC(NumSimpl, "Number of blocks simplified");
> >
> > namespace {
> > - struct CFGSimplifyPass : public FunctionPass {
> > - static char ID; // Pass identification, replacement for typeid
> > - CFGSimplifyPass() : FunctionPass(ID) {
> > - initializeCFGSimplifyPassPass(*PassRegistry::getPassRegistry());
> > - }
> > +struct CFGSimplifyPass : public FunctionPass {
> > + CFGSimplifyPass(char &ID, bool isTargetAware)
> > + : FunctionPass(ID), IsTargetAware(isTargetAware) {}
> > + virtual bool runOnFunction(Function &F);
> >
> > - virtual bool runOnFunction(Function &F);
> > + virtual void getAnalysisUsage(AnalysisUsage &AU) const {
> > + AU.addRequired<TargetTransformInfo>();
> > + }
> > +private:
> > + AliasAnalysis *AA;
> > + bool IsTargetAware; // Should the pass be target-aware?
> > +};
> > +
> > +// CFGSimplifyPass that does optimizations.
> > +struct CFGOptimize : public CFGSimplifyPass {
> > + static char ID; // Pass identification, replacement for typeid
> > +public:
> > + CFGOptimize() : CFGSimplifyPass(ID, true) {
> > + initializeCFGOptimizePass(*PassRegistry::getPassRegistry());
> > + }
> > + virtual void getAnalysisUsage(AnalysisUsage &AU) const {
> > + AU.addRequired<TargetTransformInfo>();
> > + AU.addRequired<AliasAnalysis>();
> > + }
> > +};
> >
> > - virtual void getAnalysisUsage(AnalysisUsage &AU) const {
> > - AU.addRequired<TargetTransformInfo>();
> > - }
> > - };
> > +// CFGSimplifyPass that does canonicalizations.
> > +struct CFGCanonicalize : public CFGSimplifyPass {
> > + static char ID; // Pass identification, replacement for typeid
> > +public:
> > + CFGCanonicalize() : CFGSimplifyPass(ID, false) {
> > + initializeCFGCanonicalizePass(*PassRegistry::getPassRegistry());
> > + }
> > +};
> > }
> >
> > -char CFGSimplifyPass::ID = 0;
> > -INITIALIZE_PASS_BEGIN(CFGSimplifyPass, "simplifycfg", "Simplify the CFG",
> > - false, false)
> > +char CFGCanonicalize::ID = 0;
> > +char CFGOptimize::ID = 0;
> > +INITIALIZE_PASS_BEGIN(CFGCanonicalize, "simplifycfg", "Simplify the CFG", false,
> > + false)
> > +INITIALIZE_AG_DEPENDENCY(TargetTransformInfo)
> > +INITIALIZE_PASS_END(CFGCanonicalize, "simplifycfg", "Simplify the CFG", false,
> > + false)
> > +INITIALIZE_PASS_BEGIN(CFGOptimize, "optimizecfg", "optimize the CFG", false,
> > + false)
> > INITIALIZE_AG_DEPENDENCY(TargetTransformInfo)
> > -INITIALIZE_PASS_END(CFGSimplifyPass, "simplifycfg", "Simplify the CFG",
> > - false, false)
> > +INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
> > +INITIALIZE_PASS_END(CFGOptimize, "optimizecfg", "Optimize the CFG", false,
> > + false)
> >
> > // Public interface to the CFGSimplification pass
> > -FunctionPass *llvm::createCFGSimplificationPass() {
> > - return new CFGSimplifyPass();
> > +FunctionPass *llvm::createCFGSimplificationPass(bool IsTargetAware) {
> > + if (IsTargetAware)
> > + return new CFGOptimize();
> > + else
> > + return new CFGCanonicalize();
> > }
> >
> > /// changeToUnreachable - Insert an unreachable instruction before the specified
> > @@ -301,7 +334,7 @@ static bool mergeEmptyReturnBlocks(Funct
> > /// iterativelySimplifyCFG - Call SimplifyCFG on all the blocks in the function,
> > /// iterating until no more changes are made.
> > static bool iterativelySimplifyCFG(Function &F, const TargetTransformInfo &TTI,
> > - const DataLayout *TD) {
> > + const DataLayout *TD, AliasAnalysis *AA) {
> > bool Changed = false;
> > bool LocalChange = true;
> > while (LocalChange) {
> > @@ -310,7 +343,7 @@ static bool iterativelySimplifyCFG(Funct
> > // Loop over all of the basic blocks and remove them if they are unneeded...
> > //
> > for (Function::iterator BBIt = F.begin(); BBIt != F.end(); ) {
> > - if (SimplifyCFG(BBIt++, TTI, TD)) {
> > + if (SimplifyCFG(BBIt++, TTI, TD, AA)) {
> > LocalChange = true;
> > ++NumSimpl;
> > }
> > @@ -324,11 +357,15 @@ static bool iterativelySimplifyCFG(Funct
> > // simplify the CFG.
> > //
> > bool CFGSimplifyPass::runOnFunction(Function &F) {
> > + if (IsTargetAware)
> > + AA = &getAnalysis<AliasAnalysis>();
> > + else
> > + AA = NULL;
> > const TargetTransformInfo &TTI = getAnalysis<TargetTransformInfo>();
> > const DataLayout *TD = getAnalysisIfAvailable<DataLayout>();
> > bool EverChanged = removeUnreachableBlocksFromFn(F);
> > EverChanged |= mergeEmptyReturnBlocks(F);
> > - EverChanged |= iterativelySimplifyCFG(F, TTI, TD);
> > + EverChanged |= iterativelySimplifyCFG(F, TTI, TD, AA);
> >
> > // If neither pass changed anything, we're done.
> > if (!EverChanged) return false;
> > @@ -342,7 +379,7 @@ bool CFGSimplifyPass::runOnFunction(Func
> > return true;
> >
> > do {
> > - EverChanged = iterativelySimplifyCFG(F, TTI, TD);
> > + EverChanged = iterativelySimplifyCFG(F, TTI, TD, AA);
> > EverChanged |= removeUnreachableBlocksFromFn(F);
> > } while (EverChanged);
> >
> >
> > Modified: llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp (original)
> > +++ llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp Fri Jul 26 19:01:07 2013
> > @@ -19,6 +19,7 @@
> > #include "llvm/ADT/SmallPtrSet.h"
> > #include "llvm/ADT/SmallVector.h"
> > #include "llvm/ADT/Statistic.h"
> > +#include "llvm/Analysis/AliasAnalysis.h"
> > #include "llvm/Analysis/InstructionSimplify.h"
> > #include "llvm/Analysis/TargetTransformInfo.h"
> > #include "llvm/Analysis/ValueTracking.h"
> > @@ -65,6 +66,10 @@ static cl::opt<bool>
> > HoistCondStores("simplifycfg-hoist-cond-stores", cl::Hidden, cl::init(true),
> > cl::desc("Hoist conditional stores if an unconditional store preceeds"));
> >
> > +static cl::opt<bool>
> > +ParallelAndOr("simplifycfg-parallel-and-or", cl::Hidden, cl::init(true),
> > + cl::desc("Use parallel-and-or mode for branch conditions"));
> > +
> > STATISTIC(NumBitMaps, "Number of switch instructions turned into bitmaps");
> > STATISTIC(NumLookupTables, "Number of switch instructions turned into lookup tables");
> > STATISTIC(NumSinkCommons, "Number of common instructions sunk down to the end block");
> > @@ -90,6 +95,7 @@ namespace {
> > class SimplifyCFGOpt {
> > const TargetTransformInfo &TTI;
> > const DataLayout *const TD;
> > + AliasAnalysis *AA;
> >
> > Value *isValueEqualityComparison(TerminatorInst *TI);
> > BasicBlock *GetValueEqualityComparisonCases(TerminatorInst *TI,
> > @@ -107,10 +113,25 @@ class SimplifyCFGOpt {
> > bool SimplifyIndirectBr(IndirectBrInst *IBI);
> > bool SimplifyUncondBranch(BranchInst *BI, IRBuilder <> &Builder);
> > bool SimplifyCondBranch(BranchInst *BI, IRBuilder <>&Builder);
> > + /// \brief Use parallel-and or parallel-or to generate conditions for
> > + /// conditional branches.
> > + bool SimplifyParallelAndOr(BasicBlock *BB, IRBuilder<> &Builder, Pass *P = 0);
> > + /// \brief If \param BB is the merge block of an if-region, attempt to merge
> > + /// the if-region with an adjacent if-region upstream if two if-regions
> > + /// contain identical instructions.
> > + bool MergeIfRegion(BasicBlock *BB, IRBuilder<> &Builder, Pass *P = 0);
> > + /// \brief Compare a pair of blocks: \param Block1 and \param Block2, which
> > + /// are from two if-regions whose entry blocks are \param Head1 and \param
> > + /// Head2. \returns true if \param Block1 and \param Block2 contain identical
> > + /// instructions, and have no memory reference alias with \param Head2.
> > + /// This is used as a legality check for merging if-regions.
> > + bool CompareIfRegionBlock(BasicBlock *Head1, BasicBlock *Head2,
> > + BasicBlock *Block1, BasicBlock *Block2);
> >
> > public:
> > - SimplifyCFGOpt(const TargetTransformInfo &TTI, const DataLayout *TD)
> > - : TTI(TTI), TD(TD) {}
> > + SimplifyCFGOpt(const TargetTransformInfo &TTI, const DataLayout *TD,
> > + AliasAnalysis *AA)
> > + : TTI(TTI), TD(TD), AA(AA) {}
> > bool run(BasicBlock *BB);
> > };
> > }
> > @@ -197,8 +218,8 @@ static void AddPredecessorToBlock(BasicB
> > }
> >
> >
> > -/// GetIfCondition - Given a basic block (BB) with two predecessors (and at
> > -/// least one PHI node in it), check to see if the merge at this block is due
> > +/// GetIfCondition - Given a basic block (BB) with two predecessors,
> > +/// check to see if the merge at this block is due
> > /// to an "if condition". If so, return the boolean condition that determines
> > /// which entry into BB will be taken. Also, return by references the block
> > /// that will be entered from if the condition is true, and the block that will
> > @@ -208,11 +229,26 @@ static void AddPredecessorToBlock(BasicB
> > /// instructions in them.
> > static Value *GetIfCondition(BasicBlock *BB, BasicBlock *&IfTrue,
> > BasicBlock *&IfFalse) {
> > - PHINode *SomePHI = cast<PHINode>(BB->begin());
> > - assert(SomePHI->getNumIncomingValues() == 2 &&
> > - "Function can only handle blocks with 2 predecessors!");
> > - BasicBlock *Pred1 = SomePHI->getIncomingBlock(0);
> > - BasicBlock *Pred2 = SomePHI->getIncomingBlock(1);
> > + PHINode *SomePHI = dyn_cast<PHINode>(BB->begin());
> > + BasicBlock *Pred1 = NULL;
> > + BasicBlock *Pred2 = NULL;
> > +
> > + if (SomePHI) {
> > + if (SomePHI->getNumIncomingValues() != 2)
> > + return NULL;
> > + Pred1 = SomePHI->getIncomingBlock(0);
> > + Pred2 = SomePHI->getIncomingBlock(1);
> > + } else {
> > + pred_iterator PI = pred_begin(BB), PE = pred_end(BB);
> > + if (PI == PE) // No predecessor
> > + return NULL;
> > + Pred1 = *PI++;
> > + if (PI == PE) // Only one predecessor
> > + return NULL;
> > + Pred2 = *PI++;
> > + if (PI != PE) // More than two predecessors
> > + return NULL;
> > + }
> >
> > // We can only handle branches. Other control flow will be lowered to
> > // branches if possible anyway.
> > @@ -4066,6 +4102,383 @@ bool SimplifyCFGOpt::SimplifyCondBranch(
> > return false;
> > }
> >
> > +/// If \param [in] BB has more than one predecessor that is a conditional
> > +/// branch, attempt to use parallel and/or for the branch condition. \returns
> > +/// true on success.
> > +///
> > +/// Before:
> > +/// ......
> > +/// %cmp10 = fcmp une float %tmp1, %tmp2
> > +/// br i1 %cmp1, label %if.then, label %lor.rhs
> > +///
> > +/// lor.rhs:
> > +/// ......
> > +/// %cmp11 = fcmp une float %tmp3, %tmp4
> > +/// br i1 %cmp11, label %if.then, label %ifend
> > +///
> > +/// if.end: // the merge block
> > +/// ......
> > +///
> > +/// if.then: // has two predecessors, both of them contains conditional branch.
> > +/// ......
> > +/// br label %if.end;
> > +///
> > +/// After:
> > +/// ......
> > +/// %cmp10 = fcmp une float %tmp1, %tmp2
> > +/// ......
> > +/// %cmp11 = fcmp une float %tmp3, %tmp4
> > +/// %cmp12 = or i1 %cmp10, %cmp11 // parallel-or mode.
> > +/// br i1 %cmp12, label %if.then, label %ifend
> > +///
> > +/// if.end:
> > +/// ......
> > +///
> > +/// if.then:
> > +/// ......
> > +/// br label %if.end;
> > +///
> > +/// Current implementation handles two cases.
> > +/// Case 1: \param BB is on the else-path.
> > +///
> > +/// BB1
> > +/// / |
> > +/// BB2 |
> > +/// / \ |
> > +/// BB3 \ | where, BB1, BB2 contain conditional branches.
> > +/// \ | / BB3 contains unconditional branch.
> > +/// \ | / BB4 corresponds to \param BB which is also the merge.
> > +/// BB => BB4
> > +///
> > +///
> > +/// Corresponding source code:
> > +///
> > +/// if (a == b && c == d)
> > +/// statement; // BB3
> > +///
> > +/// Case 2: \param BB BB is on the then-path.
> > +///
> > +/// BB1
> > +/// / |
> > +/// | BB2
> > +/// \ / | where BB1, BB2 contain conditional branches.
> > +/// BB => BB3 | BB3 contains unconditiona branch and corresponds
> > +/// \ / to \param BB. BB4 is the merge.
> > +/// BB4
> > +///
> > +/// Corresponding source code:
> > +///
> > +/// if (a == b || c == d)
> > +/// statement; // BB3
> > +///
> > +/// In both cases, \param BB is the common successor of conditional branches.
> > +/// In Case 1, \param BB (BB4) has an unconditional branch (BB3) as
> > +/// its predecessor. In Case 2, \param BB (BB3) only has conditional branches
> > +/// as its predecessors.
> > +///
> > +bool SimplifyCFGOpt::SimplifyParallelAndOr(BasicBlock *BB, IRBuilder<> &Builder,
> > + Pass *P) {
> > + PHINode *PHI = dyn_cast<PHINode>(BB->begin());
> > + if (PHI)
> > + return false; // For simplicity, avoid cases containing PHI nodes.
> > +
> > + BasicBlock *LastCondBlock = NULL;
> > + BasicBlock *FirstCondBlock = NULL;
> > + BasicBlock *UnCondBlock = NULL;
> > + int Idx = -1;
> > +
> > + // Check predecessors of \param BB.
> > + SmallPtrSet<BasicBlock*, 16> Preds(pred_begin(BB), pred_end(BB));
> > + for (SmallPtrSetIterator<BasicBlock*> PI = Preds.begin(), PE = Preds.end();
> > + PI != PE; ++PI) {
> > + BasicBlock *Pred = *PI;
> > + BranchInst *PBI = dyn_cast<BranchInst>(Pred->getTerminator());
> > +
> > + // All predecessors should terminate with a branch.
> > + if (!PBI)
> > + return false;
> > +
> > + BasicBlock *PP = Pred->getSinglePredecessor();
> > +
> > + if (PBI->isUnconditional()) {
> > + // Case 1: Pred (BB3) is an unconditional block, it should
> > + // have a single predecessor (BB2) that is also a predecessor
> > + // of \param BB (BB4) and should not have address-taken.
> > + // There should exist only one such unconditional
> > + // branch among the predecessors.
> > + if (UnCondBlock || !PP || (Preds.count(PP) == 0) ||
> > + Pred->hasAddressTaken())
> > + return false;
> > +
> > + UnCondBlock = Pred;
> > + continue;
> > + }
> > +
> > + // Only conditional branches are allowed beyond this point.
> > + assert(PBI->isConditional());
> > +
> > + // Condition's unique use should be the branch instruction.
> > + Value *PC = PBI->getCondition();
> > + if (!PC || !PC->hasOneUse())
> > + return false;
> > +
> > + if (PP && Preds.count(PP)) {
> > + // These are internal condition blocks to be merged from, e.g.,
> > + // BB2 in both cases.
> > + // Should not be address-taken.
> > + if (Pred->hasAddressTaken())
> > + return false;
> > +
> > + // Instructions in the internal condition blocks should be safe
> > + // to hoist up.
> > + for (BasicBlock::iterator BI = Pred->begin(), BE = PBI; BI != BE;) {
> > + Instruction *CI = BI++;
> > + if (isa<PHINode>(CI) ||
> > + !isSafeToSpeculativelyExecute(CI))
> > + return false;
> > + }
> > + } else {
> > + // This is the condition block to be merged into, e.g. BB1 in
> > + // both cases.
> > + if (FirstCondBlock)
> > + return false;
> > + FirstCondBlock = Pred;
> > + }
> > +
> > + // Find whether BB is uniformly on the true (or false) path
> > + // for all of its predecessors.
> > + BasicBlock *PS1 = PBI->getSuccessor(0);
> > + BasicBlock *PS2 = PBI->getSuccessor(1);
> > + BasicBlock *PS = (PS1 == BB) ? PS2 : PS1;
> > + int CIdx = (PS1 == BB) ? 0 : 1;
> > +
> > + if (Idx == -1)
> > + Idx = CIdx;
> > + else if (CIdx != Idx)
> > + return false;
> > +
> > + // PS is the successor which is not BB. Check successors to identify
> > + // the last conditional branch.
> > + if (Preds.count(PS) == 0) {
> > + // Case 2.
> > + // BB must have an unique successor.
> > + TerminatorInst *TBB = BB->getTerminator();
> > + if (TBB->getNumSuccessors() != 1)
> > + return false;
> > +
> > + BasicBlock *SBB = TBB->getSuccessor(0);
> > + PHI = dyn_cast<PHINode>(SBB->begin());
> > + if (PHI)
> > + return false;
> > +
> > + // PS (BB4) should be BB's successor.
> > + if (SBB != PS)
> > + return false;
> > + LastCondBlock = Pred;
> > + } else {
> > + BranchInst *BPS = dyn_cast<BranchInst>(PS->getTerminator());
> > + if (BPS && BPS->isUnconditional()) {
> > + // Case 1: PS(BB3) should be an unconditional branch.
> > + LastCondBlock = Pred;
> > + }
> > + }
> > + }
> > +
> > + if (!FirstCondBlock || !LastCondBlock || (FirstCondBlock == LastCondBlock))
> > + return false;
> > +
> > + // Do the transformation.
> > + BasicBlock *CB;
> > + bool Iteration = true;
> > + BasicBlock::iterator ItOld = Builder.GetInsertPoint();
> > + BranchInst *PBI = dyn_cast<BranchInst>(FirstCondBlock->getTerminator());
> > + Value *PC = PBI->getCondition();
> > + do {
> > + CB = PBI->getSuccessor(1 - Idx);
> > + // Delete the conditional branch.
> > + FirstCondBlock->getInstList().pop_back();
> > + FirstCondBlock->getInstList().splice(FirstCondBlock->end(), CB->getInstList());
> > + PBI = cast<BranchInst>(FirstCondBlock->getTerminator());
> > + Value *CC = PBI->getCondition();
> > + // Merge conditions.
> > + Builder.SetInsertPoint(PBI);
> > + Value *NC;
> > + if (Idx == 0)
> > + // Case 2, use parallel or.
> > + NC = Builder.CreateOr(PC, CC);
> > + else
> > + // Case 1, use parallel and.
> > + NC = Builder.CreateAnd(PC, CC);
> > +
> > + PBI->replaceUsesOfWith(CC, NC);
> > + PC = NC;
> > + if (CB == LastCondBlock)
> > + Iteration = false;
> > + // Remove internal conditional branches.
> > + CB->dropAllReferences();
> > + // make CB unreachable and let downstream to delete the block.
> > + new UnreachableInst(CB->getContext(), CB);
> > + } while (Iteration);
> > +
> > + Builder.SetInsertPoint(ItOld);
> > + DEBUG(dbgs() << "Use parallel and/or in:\n" << *FirstCondBlock);
> > + return true;
> > +}
> > +
> > +/// Compare blocks from two if-regions, where \param Head1 is the entry of the
> > +/// 1st if-region. \param Head2 is the entry of the 2nd if-region. \param
> > +/// Block1 is a block in the 1st if-region to compare. \param Block2 is a block
> > +// in the 2nd if-region to compare. \returns true if \param Block1 and \param
> > +/// Block2 have identical instructions and do not have memory reference alias
> > +/// with \param Head2.
> > +///
> > +bool SimplifyCFGOpt::CompareIfRegionBlock(BasicBlock *Head1, BasicBlock *Head2,
> > + BasicBlock *Block1, BasicBlock *Block2) {
> > + TerminatorInst *PTI2 = Head2->getTerminator();
> > + Instruction *PBI2 = Head2->begin();
> > +
> > + bool eq1 = (Block1 == Head1);
> > + bool eq2 = (Block2 == Head2);
> > + if (eq1 || eq2) {
> > + // An empty then-path or else-path.
> > + return (eq1 == eq2);
> > + }
> > +
> > + // Check whether instructions in Block1 and Block2 are identical
> > + // and do not alias with instructions in Head2.
> > + BasicBlock::iterator iter1 = Block1->begin();
> > + BasicBlock::iterator end1 = Block1->getTerminator();
> > + BasicBlock::iterator iter2 = Block2->begin();
> > + BasicBlock::iterator end2 = Block2->getTerminator();
> > +
> > + while (1) {
> > + if (iter1 == end1) {
> > + if (iter2 != end2)
> > + return false;
> > + break;
> > + }
> > +
> > + if (!iter1->isIdenticalTo(iter2))
> > + return false;
> > +
> > + // Illegal to remove instructions with side effects except
> > + // non-volatile stores.
> > + if (iter1->mayHaveSideEffects()) {
> > + Instruction *CurI = &*iter1;
> > + StoreInst *SI = dyn_cast<StoreInst>(CurI);
> > + if (!SI || SI->isVolatile())
> > + return false;
> > + }
> > +
> > + // For simplicity and speed, data dependency check can be
> > + // avoided if read from memory doesn't exist.
> > + if (iter1->mayReadFromMemory())
> > + return false;
> > +
> > + if (iter1->mayWriteToMemory()) {
> > + for (BasicBlock::iterator BI = PBI2, BE = PTI2; BI != BE; ++BI) {
> > + if (BI->mayReadFromMemory() || BI->mayWriteToMemory()) {
> > + // Check alias with Head2.
> > + if (!AA || AA->alias(iter1, BI))
> > + return false;
> > + }
> > + }
> > + }
> > + ++iter1;
> > + ++iter2;
> > + }
> > +
> > + return true;
> > +}
> > +
> > +/// Check whether \param BB is the merge block of a if-region. If yes, check
> > +/// whether there exists an adjacent if-region upstream, the two if-regions
> > +/// contain identical instuctions and can be legally merged. \returns true if
> > +/// the two if-regions are merged.
> > +///
> > +/// From:
> > +/// if (a)
> > +/// statement;
> > +/// if (b)
> > +/// statement;
> > +///
> > +/// To:
> > +/// if (a || b)
> > +/// statement;
> > +///
> > +bool SimplifyCFGOpt::MergeIfRegion(BasicBlock *BB, IRBuilder<> &Builder,
> > + Pass *P) {
> > + BasicBlock *IfTrue2, *IfFalse2;
> > + Value *IfCond2 = GetIfCondition(BB, IfTrue2, IfFalse2);
> > + Instruction *CInst2 = dyn_cast_or_null<Instruction>(IfCond2);
> > + if (!CInst2)
> > + return false;
> > +
> > + BasicBlock *SecondEntryBlock = CInst2->getParent();
> > + if (SecondEntryBlock->hasAddressTaken())
> > + return false;
> > +
> > + BasicBlock *IfTrue1, *IfFalse1;
> > + Value *IfCond1 = GetIfCondition(SecondEntryBlock, IfTrue1, IfFalse1);
> > + Instruction *CInst1 = dyn_cast_or_null<Instruction>(IfCond1);
> > + if (!CInst1)
> > + return false;
> > +
> > + BasicBlock *FirstEntryBlock = CInst1->getParent();
> > +
> > + // Either then-path or else-path should be empty.
> > + if ((IfTrue1 != FirstEntryBlock) && (IfFalse1 != FirstEntryBlock))
> > + return false;
> > + if ((IfTrue2 != SecondEntryBlock) && (IfFalse2 != SecondEntryBlock))
> > + return false;
> > +
> > + TerminatorInst *PTI2 = SecondEntryBlock->getTerminator();
> > + Instruction *PBI2 = SecondEntryBlock->begin();
> > +
> > + if (!CompareIfRegionBlock(FirstEntryBlock, SecondEntryBlock, IfTrue1, IfTrue2))
> > + return false;
> > +
> > + if (!CompareIfRegionBlock(FirstEntryBlock, SecondEntryBlock, IfFalse1, IfFalse2))
> > + return false;
> > +
> > + // Check whether \param SecondEntryBlock has side-effect and is safe to speculate.
> > + for (BasicBlock::iterator BI = PBI2, BE = PTI2; BI != BE; ++BI) {
> > + Instruction *CI = BI;
> > + if (isa<PHINode>(CI) || CI->mayHaveSideEffects() ||
> > + !isSafeToSpeculativelyExecute(CI))
> > + return false;
> > + }
> > +
> > + // Merge \param SecondEntryBlock into \param FirstEntryBlock.
> > + FirstEntryBlock->getInstList().pop_back();
> > + FirstEntryBlock->getInstList().splice(FirstEntryBlock->end(), SecondEntryBlock->getInstList());
> > + BranchInst *PBI = dyn_cast<BranchInst>(FirstEntryBlock->getTerminator());
> > + Value *CC = PBI->getCondition();
> > + BasicBlock::iterator ItOld = Builder.GetInsertPoint();
> > + Builder.SetInsertPoint(PBI);
> > + Value *NC = Builder.CreateOr(CInst1, CC);
> > + PBI->replaceUsesOfWith(CC, NC);
> > + Builder.SetInsertPoint(ItOld);
> > +
> > + // Remove IfTrue1
> > + if (IfTrue1 != FirstEntryBlock) {
> > + IfTrue1->dropAllReferences();
> > + IfTrue1->eraseFromParent();
> > + }
> > +
> > + // Remove IfFalse1
> > + if (IfFalse1 != FirstEntryBlock) {
> > + IfFalse1->dropAllReferences();
> > + IfFalse1->eraseFromParent();
> > + }
> > +
> > + // Remove \param SecondEntryBlock
> > + SecondEntryBlock->dropAllReferences();
> > + SecondEntryBlock->eraseFromParent();
> > + DEBUG(dbgs() << "If conditions merged into:\n" << *FirstEntryBlock);
> > + return true;
> > +}
> > +
> > /// Check if passing a value to an instruction will cause undefined behavior.
> > static bool passingValueIsAlwaysUndefined(Value *V, Instruction *I) {
> > Constant *C = dyn_cast<Constant>(V);
> > @@ -4168,6 +4581,11 @@ bool SimplifyCFGOpt::run(BasicBlock *BB)
> > return true;
> >
> > IRBuilder<> Builder(BB);
> > + // Whether to optimize conditional branches.
> > + bool OptCB = (ParallelAndOr && AA && TTI.hasBranchDivergence());
> > +
> > + if (OptCB && SimplifyParallelAndOr(BB, Builder))
> > + return true;
> >
> > // If there is a trivial two-entry PHI node in this basic block, and we can
> > // eliminate it, do so now.
> > @@ -4196,6 +4614,9 @@ bool SimplifyCFGOpt::run(BasicBlock *BB)
> > if (SimplifyIndirectBr(IBI)) return true;
> > }
> >
> > + if (OptCB && MergeIfRegion(BB, Builder))
> > + return true;
> > +
> > return Changed;
> > }
> >
> > @@ -4205,6 +4626,6 @@ bool SimplifyCFGOpt::run(BasicBlock *BB)
> > /// of the CFG. It returns true if a modification was made.
> > ///
> > bool llvm::SimplifyCFG(BasicBlock *BB, const TargetTransformInfo &TTI,
> > - const DataLayout *TD) {
> > - return SimplifyCFGOpt(TTI, TD).run(BB);
> > + const DataLayout *TD, AliasAnalysis *AA) {
> > + return SimplifyCFGOpt(TTI, TD, AA).run(BB);
> > }
> >
> > Modified: llvm/trunk/tools/lto/LTOCodeGenerator.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/lto/LTOCodeGenerator.cpp?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/tools/lto/LTOCodeGenerator.cpp (original)
> > +++ llvm/trunk/tools/lto/LTOCodeGenerator.cpp Fri Jul 26 19:01:07 2013
> > @@ -118,7 +118,7 @@ void LTOCodeGenerator::initializeLTOPass
> > initializeGVNPass(R);
> > initializeMemCpyOptPass(R);
> > initializeDCEPass(R);
> > - initializeCFGSimplifyPassPass(R);
> > + initializeCFGCanonicalizePass(R);
> > }
> >
> > bool LTOCodeGenerator::addModule(LTOModule* mod, std::string& errMsg) {
> >
> > Modified: llvm/trunk/tools/opt/opt.cpp
> > URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/opt/opt.cpp?rev=187278&r1=187277&r2=187278&view=diff
> > ==============================================================================
> > --- llvm/trunk/tools/opt/opt.cpp (original)
> > +++ llvm/trunk/tools/opt/opt.cpp Fri Jul 26 19:01:07 2013
> > @@ -667,6 +667,9 @@ int main(int argc, char **argv) {
> > FPasses.reset(new FunctionPassManager(M.get()));
> > if (TD)
> > FPasses->add(new DataLayout(*TD));
> > + if (TM.get())
> > + TM->addAnalysisPasses(*FPasses);
> > +
> > }
> >
> > if (PrintBreakpoints) {
> >
> >
> > _______________________________________________
> > llvm-commits mailing list
> > llvm-commits at cs.uiuc.edu
> > http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
>
> -David
>
>
> _______________________________________________
> llvm-commits mailing list
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