1 //===---- MipsOs16.cpp for Mips Option -Os16 --------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file defines an optimization phase for the MIPS target. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #define DEBUG_TYPE "mips-os16" 15 #include "MipsOs16.h" 16 #include "llvm/IR/Module.h" 17 #include "llvm/Support/Debug.h" 18 #include "llvm/Support/raw_ostream.h" 19 20 namespace { 21 22 // Figure out if we need float point based on the function signature. 23 // We need to move variables in and/or out of floating point 24 // registers because of the ABI 25 // 26 bool needsFPFromSig(Function &F) { 27 Type* RetType = F.getReturnType(); 28 switch (RetType->getTypeID()) { 29 case Type::FloatTyID: 30 case Type::DoubleTyID: 31 return true; 32 default: 33 ; 34 } 35 if (F.arg_size() >=1) { 36 Argument &Arg = F.getArgumentList().front(); 37 switch (Arg.getType()->getTypeID()) { 38 case Type::FloatTyID: 39 case Type::DoubleTyID: 40 return true; 41 default: 42 ; 43 } 44 } 45 return false; 46 } 47 48 // Figure out if the function will need floating point operations 49 // 50 bool needsFP(Function &F) { 51 if (needsFPFromSig(F)) 52 return true; 53 for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB) 54 for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); 55 I != E; ++I) { 56 const Instruction &Inst = *I; 57 switch (Inst.getOpcode()) { 58 case Instruction::FAdd: 59 case Instruction::FSub: 60 case Instruction::FMul: 61 case Instruction::FDiv: 62 case Instruction::FRem: 63 case Instruction::FPToUI: 64 case Instruction::FPToSI: 65 case Instruction::UIToFP: 66 case Instruction::SIToFP: 67 case Instruction::FPTrunc: 68 case Instruction::FPExt: 69 case Instruction::FCmp: 70 return true; 71 default: 72 ; 73 } 74 if (const CallInst *CI = dyn_cast<CallInst>(I)) { 75 DEBUG(dbgs() << "Working on call" << "\n"); 76 Function &F_ = *CI->getCalledFunction(); 77 if (needsFPFromSig(F_)) 78 return true; 79 } 80 } 81 return false; 82 } 83 } 84 namespace llvm { 85 86 87 bool MipsOs16::runOnModule(Module &M) { 88 DEBUG(errs() << "Run on Module MipsOs16\n"); 89 bool modified = false; 90 for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) { 91 if (F->isDeclaration()) continue; 92 DEBUG(dbgs() << "Working on " << F->getName() << "\n"); 93 if (needsFP(*F)) { 94 DEBUG(dbgs() << " need to compile as nomips16 \n"); 95 F->addFnAttr("nomips16"); 96 } 97 else { 98 F->addFnAttr("mips16"); 99 DEBUG(dbgs() << " no need to compile as nomips16 \n"); 100 } 101 } 102 return modified; 103 } 104 105 char MipsOs16::ID = 0; 106 107 } 108 109 ModulePass *llvm::createMipsOs16(MipsTargetMachine &TM) { 110 return new MipsOs16; 111 } 112 113 114