| //===- HexagonRemoveExtendArgs.cpp - Remove unnecessary argument sign extends // |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // Pass that removes sign extends for function parameters. These parameters |
| // are already sign extended by the caller per Hexagon's ABI |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "HexagonTargetMachine.h" |
| #include "llvm/Function.h" |
| #include "llvm/Instructions.h" |
| #include "llvm/Pass.h" |
| #include "llvm/CodeGen/MachineFunctionAnalysis.h" |
| #include "llvm/Transforms/Scalar.h" |
| |
| using namespace llvm; |
| namespace { |
| struct HexagonRemoveExtendArgs : public FunctionPass { |
| public: |
| static char ID; |
| HexagonRemoveExtendArgs() : FunctionPass(ID) {} |
| virtual bool runOnFunction(Function &F); |
| |
| const char *getPassName() const { |
| return "Remove sign extends"; |
| } |
| |
| virtual void getAnalysisUsage(AnalysisUsage &AU) const { |
| AU.addRequired<MachineFunctionAnalysis>(); |
| AU.addPreserved<MachineFunctionAnalysis>(); |
| FunctionPass::getAnalysisUsage(AU); |
| } |
| }; |
| } |
| |
| char HexagonRemoveExtendArgs::ID = 0; |
| RegisterPass<HexagonRemoveExtendArgs> X("reargs", |
| "Remove Sign and Zero Extends for Args" |
| ); |
| |
| |
| |
| bool HexagonRemoveExtendArgs::runOnFunction(Function &F) { |
| unsigned Idx = 1; |
| for (Function::arg_iterator AI = F.arg_begin(), AE = F.arg_end(); AI != AE; |
| ++AI, ++Idx) { |
| if (F.getParamAttributes(Idx).hasAttribute(Attributes::SExt)) { |
| Argument* Arg = AI; |
| if (!isa<PointerType>(Arg->getType())) { |
| for (Instruction::use_iterator UI = Arg->use_begin(); |
| UI != Arg->use_end();) { |
| if (isa<SExtInst>(*UI)) { |
| Instruction* Use = cast<Instruction>(*UI); |
| SExtInst* SI = new SExtInst(Arg, Use->getType()); |
| assert (EVT::getEVT(SI->getType()) == |
| (EVT::getEVT(Use->getType()))); |
| ++UI; |
| Use->replaceAllUsesWith(SI); |
| Instruction* First = F.getEntryBlock().begin(); |
| SI->insertBefore(First); |
| Use->eraseFromParent(); |
| } else { |
| ++UI; |
| } |
| } |
| } |
| } |
| } |
| return true; |
| } |
| |
| |
| |
| FunctionPass *llvm::createHexagonRemoveExtendOps(HexagonTargetMachine &TM) { |
| return new HexagonRemoveExtendArgs(); |
| } |