X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTransforms%2FLevelRaise.cpp;h=f246116a2ee7822ee0ce363d5f56ecb05d98a88e;hb=c966a2acee176369be2f901e32c346c176b7f772;hp=07981d0aa361759cfff328c8b1efe471ebae2571;hpb=97e52e43361e77963145b95a576db11b4d14d309;p=oota-llvm.git diff --git a/lib/Transforms/LevelRaise.cpp b/lib/Transforms/LevelRaise.cpp index 07981d0aa36..f246116a2ee 100644 --- a/lib/Transforms/LevelRaise.cpp +++ b/lib/Transforms/LevelRaise.cpp @@ -6,28 +6,51 @@ // //===----------------------------------------------------------------------===// -#include "llvm/Transforms/LevelChange.h" +#include "llvm/Transforms/RaisePointerReferences.h" +#include "llvm/Transforms/Utils/Local.h" #include "TransformInternals.h" -#include "llvm/Function.h" #include "llvm/iOther.h" #include "llvm/iMemory.h" -#include "llvm/Constants.h" #include "llvm/Pass.h" #include "llvm/ConstantHandling.h" -#include "llvm/Transforms/Scalar/DCE.h" -#include "llvm/Transforms/Scalar/ConstantProp.h" #include "llvm/Analysis/Expressions.h" +#include "llvm/Analysis/Verifier.h" +#include "llvm/Transforms/Utils/BasicBlockUtils.h" #include "Support/STLExtras.h" +#include "Support/Statistic.h" +#include "Support/CommandLine.h" #include +using std::cerr; + +// StartInst - This enables the -raise-start-inst=foo option to cause the level +// raising pass to start at instruction "foo", which is immensely useful for +// debugging! +// +static cl::opt +StartInst("raise-start-inst", cl::Hidden, cl::value_desc("inst name"), + cl::desc("Start raise pass at the instruction with the specified name")); + +static Statistic<> +NumLoadStorePeepholes("raise", "Number of load/store peepholes"); + +static Statistic<> +NumGEPInstFormed("raise", "Number of other getelementptr's formed"); + +static Statistic<> +NumExprTreesConv("raise", "Number of expression trees converted"); + +static Statistic<> +NumCastOfCast("raise", "Number of cast-of-self removed"); + +static Statistic<> +NumDCEorCP("raise", "Number of insts DCEd or constprop'd"); + +static Statistic<> +NumVarargCallChanges("raise", "Number of vararg call peepholes"); -//#define DEBUG_PEEPHOLE_INSTS 1 -#ifdef DEBUG_PEEPHOLE_INSTS #define PRINT_PEEPHOLE(ID, NUM, I) \ - std::cerr << "Inst P/H " << ID << "[" << NUM << "] " << I; -#else -#define PRINT_PEEPHOLE(ID, NUM, I) -#endif + DEBUG(std::cerr << "Inst P/H " << ID << "[" << NUM << "] " << I) #define PRINT_PEEPHOLE1(ID, I1) do { PRINT_PEEPHOLE(ID, 0, I1); } while (0) #define PRINT_PEEPHOLE2(ID, I1, I2) \ @@ -49,7 +72,6 @@ static inline bool isReinterpretingCast(const CastInst *CI) { } - // Peephole optimize the following instructions: // %t1 = cast ? to x * // %t2 = add x * %SP, %t1 ;; Constant must be 2nd operand @@ -59,16 +81,18 @@ static inline bool isReinterpretingCast(const CastInst *CI) { // static bool HandleCastToPointer(BasicBlock::iterator BI, const PointerType *DestPTy) { - CastInst *CI = cast(*BI); - if (CI->use_empty()) return false; + CastInst &CI = cast(*BI); + if (CI.use_empty()) return false; // Scan all of the uses, looking for any uses that are not add // instructions. If we have non-adds, do not make this transformation. // - for (Value::use_iterator I = CI->use_begin(), E = CI->use_end(); + for (Value::use_iterator I = CI.use_begin(), E = CI.use_end(); I != E; ++I) { if (BinaryOperator *BO = dyn_cast(*I)) { - if (BO->getOpcode() != Instruction::Add) + if (BO->getOpcode() != Instruction::Add || + // Avoid add sbyte* %X, %X cases... + BO->getOperand(0) == BO->getOperand(1)) return false; } else { return false; @@ -76,7 +100,7 @@ static bool HandleCastToPointer(BasicBlock::iterator BI, } std::vector Indices; - Value *Src = CI->getOperand(0); + Value *Src = CI.getOperand(0); const Type *Result = ConvertableToGEP(DestPTy, Src, Indices, &BI); if (Result == 0) return false; // Not convertable... @@ -84,13 +108,13 @@ static bool HandleCastToPointer(BasicBlock::iterator BI, // If we have a getelementptr capability... transform all of the // add instruction uses into getelementptr's. - while (!CI->use_empty()) { - BinaryOperator *I = cast(*CI->use_begin()); + while (!CI.use_empty()) { + BinaryOperator *I = cast(*CI.use_begin()); assert(I->getOpcode() == Instruction::Add && I->getNumOperands() == 2 && "Use is not a valid add instruction!"); // Get the value added to the cast result pointer... - Value *OtherPtr = I->getOperand((I->getOperand(0) == CI) ? 1 : 0); + Value *OtherPtr = I->getOperand((I->getOperand(0) == &CI) ? 1 : 0); Instruction *GEP = new GetElementPtrInst(OtherPtr, Indices, I->getName()); PRINT_PEEPHOLE1("cast-add-to-gep:i", I); @@ -103,16 +127,14 @@ static bool HandleCastToPointer(BasicBlock::iterator BI, // add instruction type, insert a cast now. // - // Insert the GEP instruction before the old add instruction... and get an - // iterator to point at the add instruction... - BasicBlock::iterator GEPI = InsertInstBeforeInst(GEP, I)+1; + // Insert the GEP instruction before the old add instruction... + I->getParent()->getInstList().insert(I, GEP); PRINT_PEEPHOLE1("cast-add-to-gep:o", GEP); - CastInst *CI = new CastInst(GEP, I->getType()); - GEP = CI; + GEP = new CastInst(GEP, I->getType()); // Replace the old add instruction with the shiny new GEP inst - ReplaceInstWithInst(I->getParent()->getInstList(), GEPI, GEP); + ReplaceInstWithInst(I, GEP); } PRINT_PEEPHOLE1("cast-add-to-gep:o", GEP); @@ -146,7 +168,7 @@ static bool PeepholeOptimizeAddCast(BasicBlock *BB, BasicBlock::iterator &BI, } // Only proceed if we have detected all of our conditions successfully... - if (!CompTy || !SrcPtr || !OffsetVal->getType()->isIntegral()) + if (!CompTy || !SrcPtr || !OffsetVal->getType()->isInteger()) return false; std::vector Indices; @@ -160,8 +182,7 @@ static bool PeepholeOptimizeAddCast(BasicBlock *BB, BasicBlock::iterator &BI, } GetElementPtrInst *GEP = new GetElementPtrInst(SrcPtr, Indices, - AddOp2->getName()); - BI = BB->getInstList().insert(BI, GEP)+1; + AddOp2->getName(), BI); Instruction *NCI = new CastInst(GEP, AddOp1->getType()); ReplaceInstWithInst(BB->getInstList(), BI, NCI); @@ -170,7 +191,7 @@ static bool PeepholeOptimizeAddCast(BasicBlock *BB, BasicBlock::iterator &BI, } static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { - Instruction *I = *BI; + Instruction *I = BI; if (CastInst *CI = dyn_cast(I)) { Value *Src = CI->getOperand(0); @@ -190,75 +211,69 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { CI->setName(""); Src->setName(Name, BB->getParent()->getSymbolTable()); } + + // DCE the instruction now, to avoid having the iterative version of DCE + // have to worry about it. + // + BI = BB->getInstList().erase(BI); + + ++NumCastOfCast; return true; } - // Peephole optimize the following instructions: - // %tmp = cast %V to - // %V = cast %tmp to ; Where ty & ty2 are same size - // - // Into: cast %V to - // - if (SrcI) - if (CastInst *CSrc = dyn_cast(SrcI)) - if (isReinterpretingCast(CI) + isReinterpretingCast(CSrc) < 2) { - // We can only do c-c elimination if, at most, one cast does a - // reinterpretation of the input data. - // - // If legal, make this cast refer the the original casts argument! - // - PRINT_PEEPHOLE2("cast-cast:in ", CI, CSrc); - CI->setOperand(0, CSrc->getOperand(0)); - PRINT_PEEPHOLE1("cast-cast:out", CI); - return true; - } - // Check to see if it's a cast of an instruction that does not depend on the // specific type of the operands to do it's job. if (!isReinterpretingCast(CI)) { ValueTypeCache ConvertedTypes; - // Check to see if we can convert the users of the cast value to match the - // source type of the cast... + // Check to see if we can convert the source of the cast to match the + // destination type of the cast... // ConvertedTypes[CI] = CI->getType(); // Make sure the cast doesn't change if (ExpressionConvertableToType(Src, DestTy, ConvertedTypes)) { PRINT_PEEPHOLE3("CAST-SRC-EXPR-CONV:in ", Src, CI, BB->getParent()); -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "\nCONVERTING SRC EXPR TYPE:\n"; -#endif - ValueMapCache ValueMap; - Value *E = ConvertExpressionToType(Src, DestTy, ValueMap); - if (Constant *CPV = dyn_cast(E)) - CI->replaceAllUsesWith(CPV); + DEBUG(cerr << "\nCONVERTING SRC EXPR TYPE:\n"); + { // ValueMap must be destroyed before function verified! + ValueMapCache ValueMap; + Value *E = ConvertExpressionToType(Src, DestTy, ValueMap); + if (Constant *CPV = dyn_cast(E)) + CI->replaceAllUsesWith(CPV); + + PRINT_PEEPHOLE1("CAST-SRC-EXPR-CONV:out", E); + DEBUG(cerr << "DONE CONVERTING SRC EXPR TYPE: \n" << BB->getParent()); + } + + DEBUG(assert(verifyFunction(*BB->getParent()) == false && + "Function broken!")); BI = BB->begin(); // Rescan basic block. BI might be invalidated. - PRINT_PEEPHOLE1("CAST-SRC-EXPR-CONV:out", E); -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "DONE CONVERTING SRC EXPR TYPE: \n" << BB->getParent(); -#endif + ++NumExprTreesConv; return true; } - // Check to see if we can convert the source of the cast to match the - // destination type of the cast... + // Check to see if we can convert the users of the cast value to match the + // source type of the cast... // ConvertedTypes.clear(); + // Make sure the source doesn't change type + ConvertedTypes[Src] = Src->getType(); if (ValueConvertableToType(CI, Src->getType(), ConvertedTypes)) { PRINT_PEEPHOLE3("CAST-DEST-EXPR-CONV:in ", Src, CI, BB->getParent()); -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "\nCONVERTING EXPR TYPE:\n"; -#endif - ValueMapCache ValueMap; - ConvertValueToNewType(CI, Src, ValueMap); // This will delete CI! + DEBUG(cerr << "\nCONVERTING EXPR TYPE:\n"); + { // ValueMap must be destroyed before function verified! + ValueMapCache ValueMap; + ConvertValueToNewType(CI, Src, ValueMap); // This will delete CI! + } - BI = BB->begin(); // Rescan basic block. BI might be invalidated. PRINT_PEEPHOLE1("CAST-DEST-EXPR-CONV:out", Src); -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "DONE CONVERTING EXPR TYPE: \n\n" << BB->getParent(); -#endif + DEBUG(cerr << "DONE CONVERTING EXPR TYPE: \n\n" << BB->getParent()); + + DEBUG(assert(verifyFunction(*BB->getParent()) == false && + "Function broken!")); + BI = BB->begin(); // Rescan basic block. BI might be invalidated. + ++NumExprTreesConv; return true; } } @@ -270,6 +285,7 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { if (const PointerType *DestPTy = dyn_cast(DestTy)) { if (HandleCastToPointer(BI, DestPTy)) { BI = BB->begin(); // Rescan basic block. BI might be invalidated. + ++NumGEPInstFormed; return true; } } @@ -284,7 +300,6 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { // Into: %t2 = getelementptr {<...>} * %StructPtr, <0, 0, 0, ...> // %t1 = cast * %t1 to * // -#if 1 if (const CompositeType *CTy = getPointedToComposite(Src->getType())) if (const PointerType *DestPTy = dyn_cast(DestTy)) { @@ -312,7 +327,7 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { // Build the index vector, full of all zeros std::vector Indices; - Indices.push_back(ConstantUInt::get(Type::UIntTy, 0)); + Indices.push_back(ConstantSInt::get(Type::LongTy, 0)); while (CurCTy && !isa(CurCTy)) { if (const StructType *CurSTy = dyn_cast(CurCTy)) { // Check for a zero element struct type... if we have one, bail. @@ -327,7 +342,7 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { } // Insert a zero to index through this type... - Indices.push_back(ConstantUInt::get(CurCTy->getIndexType(), 0)); + Indices.push_back(Constant::getNullValue(CurCTy->getIndexType())); // Did we find what we're looking for? if (ElTy->isLosslesslyConvertableTo(DestPointedTy)) break; @@ -342,11 +357,11 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { if (ElTy) { PRINT_PEEPHOLE1("cast-for-first:in", CI); + std::string Name = CI->getName(); CI->setName(""); + // Insert the new T cast instruction... stealing old T's name GetElementPtrInst *GEP = new GetElementPtrInst(Src, Indices, - CI->getName()); - CI->setName(""); - BI = BB->getInstList().insert(BI, GEP)+1; + Name, BI); // Make the old cast instruction reference the new GEP instead of // the old src value. @@ -354,13 +369,12 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { CI->setOperand(0, GEP); PRINT_PEEPHOLE2("cast-for-first:out", GEP, CI); + ++NumGEPInstFormed; return true; } } } -#endif -#if 1 } else if (StoreInst *SI = dyn_cast(I)) { Value *Val = SI->getOperand(0); Value *Pointer = SI->getPointerOperand(); @@ -380,22 +394,59 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { // if (CastInst *CI = dyn_cast(Pointer)) if (Value *CastSrc = CI->getOperand(0)) // CSPT = CastSrcPointerType - if (PointerType *CSPT = dyn_cast(CastSrc->getType())) + if (const PointerType *CSPT = dyn_cast(CastSrc->getType())) // convertable types? - if (Val->getType()->isLosslesslyConvertableTo(CSPT->getElementType()) && - !SI->hasIndices()) { // No subscripts yet! + if (Val->getType()->isLosslesslyConvertableTo(CSPT->getElementType())) { PRINT_PEEPHOLE3("st-src-cast:in ", Pointer, Val, SI); // Insert the new T cast instruction... stealing old T's name + std::string Name(CI->getName()); CI->setName(""); CastInst *NCI = new CastInst(Val, CSPT->getElementType(), - CI->getName()); - CI->setName(""); - BI = BB->getInstList().insert(BI, NCI)+1; + Name, BI); // Replace the old store with a new one! ReplaceInstWithInst(BB->getInstList(), BI, SI = new StoreInst(NCI, CastSrc)); PRINT_PEEPHOLE3("st-src-cast:out", NCI, CastSrc, SI); + ++NumLoadStorePeepholes; + return true; + } + + } else if (LoadInst *LI = dyn_cast(I)) { + Value *Pointer = LI->getOperand(0); + const Type *PtrElType = + cast(Pointer->getType())->getElementType(); + + // Peephole optimize the following instructions: + // %Val = cast * to * ;; If T1 is losslessly convertable to T2 + // %t = load * %P + // + // Into: + // %t = load * %P + // %Val = cast to + // + // Note: This is not taken care of by expr conversion because there might + // not be a cast available for the store to convert the incoming value of. + // This code is basically here to make sure that pointers don't have casts + // if possible. + // + if (CastInst *CI = dyn_cast(Pointer)) + if (Value *CastSrc = CI->getOperand(0)) // CSPT = CastSrcPointerType + if (const PointerType *CSPT = dyn_cast(CastSrc->getType())) + // convertable types? + if (PtrElType->isLosslesslyConvertableTo(CSPT->getElementType())) { + PRINT_PEEPHOLE2("load-src-cast:in ", Pointer, LI); + + // Create the new load instruction... loading the pre-casted value + LoadInst *NewLI = new LoadInst(CastSrc, LI->getName(), BI); + + // Insert the new T cast instruction... stealing old T's name + CastInst *NCI = new CastInst(NewLI, LI->getType(), CI->getName()); + + // Replace the old store with a new one! + ReplaceInstWithInst(BB->getInstList(), BI, NCI); + PRINT_PEEPHOLE3("load-src-cast:out", NCI, CastSrc, NewLI); + ++NumLoadStorePeepholes; return true; } @@ -403,10 +454,44 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { isa(I->getOperand(1))) { if (PeepholeOptimizeAddCast(BB, BI, I->getOperand(0), - cast(I->getOperand(1)))) + cast(I->getOperand(1)))) { + ++NumGEPInstFormed; return true; + } + } else if (CallInst *CI = dyn_cast(I)) { + // If we have a call with all varargs arguments, convert the call to use the + // actual argument types present... + // + const PointerType *PTy = cast(CI->getCalledValue()->getType()); + const FunctionType *FTy = cast(PTy->getElementType()); + + // Is the call to a vararg variable with no real parameters? + if (FTy->isVarArg() && FTy->getNumParams() == 0) { + // If so, insert a new cast instruction, casting it to a function type + // that matches the current arguments... + // + std::vector Params; // Parameter types... + for (unsigned i = 1, e = CI->getNumOperands(); i != e; ++i) + Params.push_back(CI->getOperand(i)->getType()); + + FunctionType *NewFT = FunctionType::get(FTy->getReturnType(), + Params, false); + PointerType *NewPFunTy = PointerType::get(NewFT); + + // Create a new cast, inserting it right before the function call... + CastInst *NewCast = new CastInst(CI->getCalledValue(), NewPFunTy, + CI->getCalledValue()->getName(), CI); + + // Create a new call instruction... + CallInst *NewCall = new CallInst(NewCast, + std::vector(CI->op_begin()+1, CI->op_end())); + ++BI; + ReplaceInstWithInst(CI, NewCall); + + ++NumVarargCallChanges; + return true; + } -#endif } return false; @@ -415,27 +500,22 @@ static bool PeepholeOptimize(BasicBlock *BB, BasicBlock::iterator &BI) { -static bool DoRaisePass(Function *F) { +static bool DoRaisePass(Function &F) { bool Changed = false; - for (Function::iterator MI = F->begin(), ME = F->end(); MI != ME; ++MI) { - BasicBlock *BB = *MI; - BasicBlock::InstListType &BIL = BB->getInstList(); - + for (Function::iterator BB = F.begin(), BBE = F.end(); BB != BBE; ++BB) for (BasicBlock::iterator BI = BB->begin(); BI != BB->end();) { -#if DEBUG_PEEPHOLE_INSTS - cerr << "Processing: " << *BI; -#endif - if (dceInstruction(BIL, BI) || doConstantPropogation(BB, BI)) { + DEBUG(cerr << "Processing: " << *BI); + if (dceInstruction(BI) || doConstantPropogation(BI)) { Changed = true; -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "***\t\t^^-- DeadCode Elinated!\n"; -#endif - } else if (PeepholeOptimize(BB, BI)) + ++NumDCEorCP; + DEBUG(cerr << "***\t\t^^-- Dead code eliminated!\n"); + } else if (PeepholeOptimize(BB, BI)) { Changed = true; - else + } else { ++BI; + } } - } + return Changed; } @@ -443,20 +523,31 @@ static bool DoRaisePass(Function *F) { // RaisePointerReferences::doit - Raise a function representation to a higher // level. // -static bool doRPR(Function *F) { -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "\n\n\nStarting to work on Function '" << F->getName() << "'\n"; -#endif +static bool doRPR(Function &F) { + DEBUG(cerr << "\n\n\nStarting to work on Function '" << F.getName() << "'\n"); // Insert casts for all incoming pointer pointer values that are treated as // arrays... // bool Changed = false, LocalChange; + + // If the StartInst option was specified, then Peephole optimize that + // instruction first if it occurs in this function. + // + if (!StartInst.empty()) { + for (Function::iterator BB = F.begin(), BBE = F.end(); BB != BBE; ++BB) + for (BasicBlock::iterator BI = BB->begin(); BI != BB->end(); ++BI) + if (BI->getName() == StartInst) { + bool SavedDebug = DebugFlag; // Save the DEBUG() controlling flag. + DebugFlag = true; // Turn on DEBUG's + Changed |= PeepholeOptimize(BB, BI); + DebugFlag = SavedDebug; // Restore DebugFlag to previous state + } + } + do { -#ifdef DEBUG_PEEPHOLE_INSTS - cerr << "Looping: \n" << F; -#endif + DEBUG(cerr << "Looping: \n" << F); // Iterate over the function, refining it, until it converges on a stable // state @@ -471,7 +562,11 @@ static bool doRPR(Function *F) { namespace { struct RaisePointerReferences : public FunctionPass { - virtual bool runOnFunction(Function *F) { return doRPR(F); } + + // FIXME: constructor should save and use target data here!! + RaisePointerReferences(const TargetData &TD) {} + + virtual bool runOnFunction(Function &F) { return doRPR(F); } virtual void getAnalysisUsage(AnalysisUsage &AU) const { AU.preservesCFG(); @@ -479,8 +574,9 @@ namespace { }; } -Pass *createRaisePointerReferencesPass() { - return new RaisePointerReferences(); +Pass *createRaisePointerReferencesPass(const TargetData &TD) { + return new RaisePointerReferences(TD); } - +static RegisterOpt +X("raise", "Raise Pointer References", createRaisePointerReferencesPass);