X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTransforms%2FUtils%2FLowerAllocations.cpp;h=8c6550003dd72b0dbe78a4c0ca89148bc83349a2;hb=dee430d26e14a3d7c8d86688d49ac8b116aa044f;hp=3ee74d49c7fc88a58701123b932da7ba9e3ccecc;hpb=79df7c0aaa18129e55968c8783ef8346807bd4af;p=oota-llvm.git diff --git a/lib/Transforms/Utils/LowerAllocations.cpp b/lib/Transforms/Utils/LowerAllocations.cpp index 3ee74d49c7f..8c6550003dd 100644 --- a/lib/Transforms/Utils/LowerAllocations.cpp +++ b/lib/Transforms/Utils/LowerAllocations.cpp @@ -1,125 +1,93 @@ -//===- ChangeAllocations.cpp - Modify %malloc & %free calls -----------------=// +//===- LowerAllocations.cpp - Reduce malloc & free insts to calls ---------===// // -// This file defines two passes that convert malloc and free instructions to -// calls to and from %malloc & %free function calls. The LowerAllocations -// transformation is a target dependant tranformation because it depends on the -// size of data types and alignment constraints. +// The LowerAllocations transformation is a target dependant tranformation +// because it depends on the size of data types and alignment constraints. // //===----------------------------------------------------------------------===// -#include "llvm/Transforms/ChangeAllocations.h" -#include "llvm/Target/TargetData.h" +#include "llvm/Transforms/Scalar.h" #include "llvm/Module.h" #include "llvm/DerivedTypes.h" #include "llvm/iMemory.h" #include "llvm/iOther.h" -#include "llvm/SymbolTable.h" -#include "llvm/ConstantVals.h" +#include "llvm/Constants.h" #include "llvm/Pass.h" -#include "TransformInternals.h" +#include "llvm/Target/TargetData.h" +#include "Support/Statistic.h" + using std::vector; namespace { + Statistic<> NumLowered("lowerallocs", "Number of allocations lowered"); + + /// LowerAllocations - Turn malloc and free instructions into %malloc and + /// %free calls. + /// + class LowerAllocations : public BasicBlockPass { + Function *MallocFunc; // Functions in the module we are processing + Function *FreeFunc; // Initialized by doInitialization + public: + LowerAllocations() : MallocFunc(0), FreeFunc(0) {} + + virtual void getAnalysisUsage(AnalysisUsage &AU) const { + AU.addRequired(); + } -// LowerAllocations - Turn malloc and free instructions into %malloc and %free -// calls. -// -class LowerAllocations : public BasicBlockPass { - Function *MallocFunc; // Functions in the module we are processing - Function *FreeFunc; // Initialized by doInitialization - - const TargetData &DataLayout; -public: - inline LowerAllocations(const TargetData &TD) : DataLayout(TD) { - MallocFunc = FreeFunc = 0; - } - - // doPassInitialization - For the lower allocations pass, this ensures that a - // module contains a declaration for a malloc and a free function. - // - bool doInitialization(Module *M); - - // runOnBasicBlock - This method does the actual work of converting - // instructions over, assuming that the pass has already been initialized. - // - bool runOnBasicBlock(BasicBlock *BB); -}; - -// RaiseAllocations - Turn %malloc and %free calls into the appropriate -// instruction. -// -class RaiseAllocations : public BasicBlockPass { - Function *MallocFunc; // Functions in the module we are processing - Function *FreeFunc; // Initialized by doPassInitializationVirt -public: - inline RaiseAllocations() : MallocFunc(0), FreeFunc(0) {} - - // doPassInitialization - For the raise allocations pass, this finds a - // declaration for malloc and free if they exist. - // - bool doInitialization(Module *M); + /// doPassInitialization - For the lower allocations pass, this ensures that + /// a module contains a declaration for a malloc and a free function. + /// + bool doInitialization(Module &M); + + /// runOnBasicBlock - This method does the actual work of converting + /// instructions over, assuming that the pass has already been initialized. + /// + bool runOnBasicBlock(BasicBlock &BB); + }; + + RegisterOpt + X("lowerallocs", "Lower allocations from instructions to calls"); +} - // runOnBasicBlock - This method does the actual work of converting - // instructions over, assuming that the pass has already been initialized. - // - bool runOnBasicBlock(BasicBlock *BB); -}; +// createLowerAllocationsPass - Interface to this file... +Pass *createLowerAllocationsPass() { + return new LowerAllocations(); +} -} // end anonymous namespace // doInitialization - For the lower allocations pass, this ensures that a // module contains a declaration for a malloc and a free function. // // This function is always successful. // -bool LowerAllocations::doInitialization(Module *M) { - bool Changed = false; - const MethodType *MallocType = - MethodType::get(PointerType::get(Type::SByteTy), - vector(1, Type::UIntTy), false); - - SymbolTable *SymTab = M->getSymbolTableSure(); - - // Check for a definition of malloc - if (Value *V = SymTab->lookup(PointerType::get(MallocType), "malloc")) { - MallocFunc = cast(V); // Yup, got it - } else { // Nope, add one - M->getFunctionList().push_back(MallocFunc = new Function(MallocType, false, - "malloc")); - Changed = true; - } - - const MethodType *FreeType = - MethodType::get(Type::VoidTy, - vector(1, PointerType::get(Type::SByteTy)), - false); - - // Check for a definition of free - if (Value *V = SymTab->lookup(PointerType::get(FreeType), "free")) { - FreeFunc = cast(V); // Yup, got it - } else { // Nope, add one - FreeFunc = new Function(FreeType, false,"free"); - M->getFunctionList().push_back(FreeFunc); - Changed = true; - } - - return Changed; +bool LowerAllocations::doInitialization(Module &M) { + const FunctionType *MallocType = + FunctionType::get(PointerType::get(Type::SByteTy), + vector(1, Type::UIntTy), false); + const FunctionType *FreeType = + FunctionType::get(Type::VoidTy, + vector(1, PointerType::get(Type::SByteTy)), + false); + + MallocFunc = M.getOrInsertFunction("malloc", MallocType); + FreeFunc = M.getOrInsertFunction("free" , FreeType); + + return true; } // runOnBasicBlock - This method does the actual work of converting // instructions over, assuming that the pass has already been initialized. // -bool LowerAllocations::runOnBasicBlock(BasicBlock *BB) { +bool LowerAllocations::runOnBasicBlock(BasicBlock &BB) { bool Changed = false; - assert(MallocFunc && FreeFunc && BB && "Pass not initialized!"); + assert(MallocFunc && FreeFunc && "Pass not initialized!"); + + BasicBlock::InstListType &BBIL = BB.getInstList(); + TargetData &DataLayout = getAnalysis(); // Loop over all of the instructions, looking for malloc or free instructions - for (unsigned i = 0; i < BB->size(); ++i) { - BasicBlock::InstListType &BBIL = BB->getInstList(); - if (MallocInst *MI = dyn_cast(*(BBIL.begin()+i))) { - BBIL.remove(BBIL.begin()+i); // remove the malloc instr... - - const Type *AllocTy =cast(MI->getType())->getElementType(); + for (BasicBlock::iterator I = BB.begin(), E = BB.end(); I != E; ++I) { + if (MallocInst *MI = dyn_cast(&*I)) { + const Type *AllocTy = MI->getType()->getElementType(); // Get the number of bytes to be allocated for one element of the // requested type... @@ -131,111 +99,36 @@ bool LowerAllocations::runOnBasicBlock(BasicBlock *BB) { MallocArg = MI->getOperand(0); // Operand * 1 = Operand } else if (MI->getNumOperands()) { // Multiply it by the array size if neccesary... - MallocArg = BinaryOperator::create(Instruction::Mul,MI->getOperand(0), - MallocArg); - BBIL.insert(BBIL.begin()+i++, cast(MallocArg)); + MallocArg = BinaryOperator::create(Instruction::Mul, MI->getOperand(0), + MallocArg, "", I); } // Create the call to Malloc... CallInst *MCall = new CallInst(MallocFunc, - vector(1, MallocArg)); - BBIL.insert(BBIL.begin()+i, MCall); + vector(1, MallocArg), "", I); // Create a cast instruction to convert to the right type... - CastInst *MCast = new CastInst(MCall, MI->getType()); - BBIL.insert(BBIL.begin()+i+1, MCast); + CastInst *MCast = new CastInst(MCall, MI->getType(), "", I); // Replace all uses of the old malloc inst with the cast inst MI->replaceAllUsesWith(MCast); - delete MI; // Delete the malloc inst + I = --BBIL.erase(I); // remove and delete the malloc instr... Changed = true; - } else if (FreeInst *FI = dyn_cast(*(BBIL.begin()+i))) { - BBIL.remove(BB->getInstList().begin()+i); - + ++NumLowered; + } else if (FreeInst *FI = dyn_cast(&*I)) { // Cast the argument to free into a ubyte*... CastInst *MCast = new CastInst(FI->getOperand(0), - PointerType::get(Type::UByteTy)); - BBIL.insert(BBIL.begin()+i, MCast); + PointerType::get(Type::UByteTy), "", I); // Insert a call to the free function... - CallInst *FCall = new CallInst(FreeFunc, - vector(1, MCast)); - BBIL.insert(BBIL.begin()+i+1, FCall); + CallInst *FCall = new CallInst(FreeFunc, vector(1, MCast), "", I); // Delete the old free instruction - delete FI; + I = --BBIL.erase(I); Changed = true; + ++NumLowered; } } return Changed; } - -bool RaiseAllocations::doInitialization(Module *M) { - SymbolTable *ST = M->getSymbolTable(); - if (!ST) return false; - - // If the module has a symbol table, they might be referring to the malloc - // and free functions. If this is the case, grab the method pointers that - // the module is using. - // - // Lookup %malloc and %free in the symbol table, for later use. If they - // don't exist, or are not external, we do not worry about converting calls - // to that function into the appropriate instruction. - // - const PointerType *MallocType = // Get the type for malloc - PointerType::get(MethodType::get(PointerType::get(Type::SByteTy), - vector(1, Type::UIntTy), false)); - MallocFunc = cast_or_null(ST->lookup(MallocType, "malloc")); - if (MallocFunc && !MallocFunc->isExternal()) - MallocFunc = 0; // Don't mess with locally defined versions of the fn - - const PointerType *FreeType = // Get the type for free - PointerType::get(MethodType::get(Type::VoidTy, - vector(1, PointerType::get(Type::SByteTy)), false)); - FreeFunc = cast_or_null(ST->lookup(FreeType, "free")); - if (FreeFunc && !FreeFunc->isExternal()) - FreeFunc = 0; // Don't mess with locally defined versions of the fn - - return false; -} - -// doOneCleanupPass - Do one pass over the input method, fixing stuff up. -// -bool RaiseAllocations::runOnBasicBlock(BasicBlock *BB) { - bool Changed = false; - BasicBlock::InstListType &BIL = BB->getInstList(); - - for (BasicBlock::iterator BI = BB->begin(); BI != BB->end();) { - Instruction *I = *BI; - - if (CallInst *CI = dyn_cast(I)) { - if (CI->getCalledValue() == MallocFunc) { // Replace call to malloc? - const Type *PtrSByte = PointerType::get(Type::SByteTy); - MallocInst *MallocI = new MallocInst(PtrSByte, CI->getOperand(1), - CI->getName()); - CI->setName(""); - ReplaceInstWithInst(BIL, BI, MallocI); - Changed = true; - continue; // Skip the ++BI - } else if (CI->getCalledValue() == FreeFunc) { // Replace call to free? - ReplaceInstWithInst(BIL, BI, new FreeInst(CI->getOperand(1))); - Changed = true; - continue; // Skip the ++BI - } - } - - ++BI; - } - - return Changed; -} - -Pass *createLowerAllocationsPass(const TargetData &TD) { - return new LowerAllocations(TD); -} -Pass *createRaiseAllocationsPass() { - return new RaiseAllocations(); -} - -