llvm-6502/lib/CodeGen/MachineInstrAnnot.cpp

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//===-- MachineInstrAnnot.cpp ---------------------------------------------===//
//
// This file defines Annotations used to pass information between code
// generation phases.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/MachineInstrAnnot.h"
#include "llvm/CodeGen/InstrSelection.h"
#include "llvm/CodeGen/InstrSelectionSupport.h"
#include "llvm/CodeGen/MachineCodeForInstruction.h"
#include "llvm/iOther.h"
#include "llvm/Type.h"
CallArgsDescriptor::CallArgsDescriptor(const CallInst* _callInstr,
TmpInstruction* _retAddrReg,
bool _isVarArgs, bool _noPrototype)
: callInstr(_callInstr),
funcPtr(isa<Function>(_callInstr->getCalledValue())
? NULL : _callInstr->getCalledValue()),
retAddrReg(_retAddrReg),
isVarArgs(_isVarArgs),
noPrototype(_noPrototype)
{
unsigned int numArgs = callInstr->getNumOperands();
argInfoVec.reserve(numArgs);
assert(callInstr->getOperand(0) == callInstr->getCalledValue()
&& "Operand 0 is ignored in the loop below!");
for (unsigned int i=1; i < numArgs; ++i)
argInfoVec.push_back(CallArgInfo(callInstr->getOperand(i)));
// Enter this object in the MachineCodeForInstr object of the CallInst.
// This transfers ownership of this object.
MachineCodeForInstruction::get(callInstr).setCallArgsDescriptor(this);
}
const CallInst*
CallArgsDescriptor::getReturnValue() const
{
return (callInstr->getType() == Type::VoidTy? NULL : callInstr);
}
// Mechanism to get the descriptor for a CALL MachineInstr.
// We get the LLVM CallInstr from the ret. addr. register argument
// of the CALL MachineInstr (which is explicit operand #3 for indirect
// calls or the last implicit operand for direct calls). We then get
// the CallArgsDescriptor from the MachineCodeForInstruction object for
// the CallInstr.
// This is roundabout but avoids adding a new map or annotation just
// to keep track of CallArgsDescriptors.
//
CallArgsDescriptor *CallArgsDescriptor::get(const MachineInstr* MI)
{
const TmpInstruction* retAddrReg =
cast<TmpInstruction>(isa<Function>(MI->getOperand(0).getVRegValue())
? MI->getImplicitRef(MI->getNumImplicitRefs()-1)
: MI->getOperand(2).getVRegValue());
assert(retAddrReg->getNumOperands() == 1 &&
isa<CallInst>(retAddrReg->getOperand(0)) &&
"Location of callInstr arg for CALL instr. changed? FIX THIS CODE!");
const CallInst* callInstr = cast<CallInst>(retAddrReg->getOperand(0));
CallArgsDescriptor* desc =
MachineCodeForInstruction::get(callInstr).getCallArgsDescriptor();
assert(desc->getCallInst()==callInstr && "Incorrect call args descriptor?");
return desc;
}