LLVM API Documentation
00001 //===-- MachineCodeForInstruction.cpp -------------------------------------===// 00002 // 00003 // The LLVM Compiler Infrastructure 00004 // 00005 // This file was developed by the LLVM research group and is distributed under 00006 // the University of Illinois Open Source License. See LICENSE.TXT for details. 00007 // 00008 //===----------------------------------------------------------------------===// 00009 // 00010 // Container for the sequence of MachineInstrs created for a single 00011 // LLVM Instruction. MachineCodeForInstruction also tracks temporary values 00012 // (TmpInstruction objects) created during SparcV9 code generation, so that 00013 // they can be deleted when they are no longer needed, and finally, it also 00014 // holds some extra information for 'call' Instructions (using the 00015 // CallArgsDescriptor object, which is also implemented in this file). 00016 // 00017 //===----------------------------------------------------------------------===// 00018 00019 #include "MachineCodeForInstruction.h" 00020 #include "llvm/Function.h" 00021 #include "llvm/Instructions.h" 00022 #include "llvm/Type.h" 00023 #include "llvm/CodeGen/MachineInstr.h" 00024 #include "llvm/CodeGen/MachineFunction.h" 00025 #include "MachineFunctionInfo.h" 00026 #include "MachineInstrAnnot.h" 00027 #include "SparcV9TmpInstr.h" 00028 #include "SparcV9RegisterInfo.h" 00029 using namespace llvm; 00030 00031 MachineCodeForInstruction &MachineCodeForInstruction::get(const Instruction *I){ 00032 MachineFunction &MF = MachineFunction::get(I->getParent()->getParent()); 00033 return MF.getInfo<SparcV9FunctionInfo>()->MCFIEntries[I]; 00034 } 00035 00036 void MachineCodeForInstruction::destroy(const Instruction *I) { 00037 MachineFunction &MF = MachineFunction::get(I->getParent()->getParent()); 00038 MF.getInfo<SparcV9FunctionInfo>()->MCFIEntries.erase(I); 00039 } 00040 00041 void MachineCodeForInstruction::dropAllReferences() { 00042 for (unsigned i=0, N=tempVec.size(); i < N; i++) 00043 cast<Instruction>(tempVec[i])->dropAllReferences(); 00044 } 00045 00046 MachineCodeForInstruction::~MachineCodeForInstruction() { 00047 // Let go of all uses in temp. instructions 00048 dropAllReferences(); 00049 00050 // Free the Value objects created to hold intermediate values 00051 for (unsigned i=0, N=tempVec.size(); i < N; i++) 00052 delete tempVec[i]; 00053 00054 // do not free the MachineInstr objects allocated. they are managed 00055 // by the ilist in MachineBasicBlock 00056 00057 // Free the CallArgsDescriptor if it exists. 00058 delete callArgsDesc; 00059 } 00060 00061 CallArgsDescriptor::CallArgsDescriptor(CallInst* _callInstr, 00062 TmpInstruction* _retAddrReg, 00063 bool _isVarArgs, bool _noPrototype) 00064 : callInstr(_callInstr), 00065 funcPtr(isa<Function>(_callInstr->getCalledValue()) 00066 ? NULL : _callInstr->getCalledValue()), 00067 retAddrReg(_retAddrReg), 00068 isVarArgs(_isVarArgs), 00069 noPrototype(_noPrototype) { 00070 unsigned int numArgs = callInstr->getNumOperands(); 00071 argInfoVec.reserve(numArgs); 00072 assert(callInstr->getOperand(0) == callInstr->getCalledValue() 00073 && "Operand 0 is ignored in the loop below!"); 00074 for (unsigned int i=1; i < numArgs; ++i) 00075 argInfoVec.push_back(CallArgInfo(callInstr->getOperand(i))); 00076 00077 // Enter this object in the MachineCodeForInstr object of the CallInst. 00078 // This transfers ownership of this object. 00079 MachineCodeForInstruction::get(callInstr).setCallArgsDescriptor(this); 00080 } 00081 00082 CallInst *CallArgsDescriptor::getReturnValue() const { 00083 return (callInstr->getType() == Type::VoidTy? NULL : callInstr); 00084 } 00085 00086 /// CallArgsDescriptor::get - Mechanism to get the descriptor for a CALL 00087 /// MachineInstr. We get the LLVM CallInst from the return-address register 00088 /// argument of the CALL MachineInstr (which is explicit operand #2 for 00089 /// indirect calls or the last implicit operand for direct calls). We then get 00090 /// the CallArgsDescriptor from the MachineCodeForInstruction object for the 00091 /// CallInstr. This is roundabout but avoids adding a new map or annotation 00092 /// just to keep track of CallArgsDescriptors. 00093 /// 00094 CallArgsDescriptor *CallArgsDescriptor::get(const MachineInstr *MI) { 00095 const Value *retAddrVal = 0; 00096 if ((MI->getOperand (0).getType () == MachineOperand::MO_MachineRegister 00097 && MI->getOperand (0).getReg () == SparcV9::g0) 00098 || (MI->getOperand (0).getType () == MachineOperand::MO_VirtualRegister 00099 && !isa<Function> (MI->getOperand (0).getVRegValue ()))) { 00100 retAddrVal = MI->getOperand (2).getVRegValue (); 00101 } else { 00102 retAddrVal = MI->getImplicitRef (MI->getNumImplicitRefs () - 1); 00103 } 00104 00105 const TmpInstruction* retAddrReg = cast<TmpInstruction> (retAddrVal); 00106 assert(retAddrReg->getNumOperands() == 1 && 00107 isa<CallInst>(retAddrReg->getOperand(0)) && 00108 "Location of callInstr arg for CALL instr. changed? FIX THIS CODE!"); 00109 00110 const CallInst* callInstr = cast<CallInst>(retAddrReg->getOperand(0)); 00111 00112 CallArgsDescriptor* desc = 00113 MachineCodeForInstruction::get(callInstr).getCallArgsDescriptor(); 00114 assert(desc->getCallInst()==callInstr && "Incorrect call args descriptor?"); 00115 return desc; 00116 }