replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Use live out sets for return values instead of imp_defs, which is cleaner and faster. 

llvm-svn: 21181
This commit is contained in:
Chris Lattner 2005-04-09 15:23:56 +00:00
parent 4c6ab01a20
commit b59006c4a1
2 changed files with 41 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
llvm/lib/Target/X86/X86ISelPattern.cpp
View File

@ -160,6 +160,26 @@ X86TargetLowering::LowerArguments(Function &F, SelectionDAG &DAG) {
if (F.isVarArg())
VarArgsFrameIndex = MFI->CreateFixedObject(1, ArgOffset);
ReturnAddrIndex = 0; // No return address slot generated yet.
// Finally, inform the code generator which regs we return values in.
switch (getValueType(F.getReturnType())) {
default: assert(0 && "Unknown type!");
case MVT::isVoid: break;
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
MF.addLiveOut(X86::EAX);
break;
case MVT::i64:
MF.addLiveOut(X86::EAX);
MF.addLiveOut(X86::EDX);
break;
case MVT::f32:
case MVT::f64:
MF.addLiveOut(X86::ST0);
break;
}
return ArgValues;
}
@ -2929,9 +2949,6 @@ void ISel::Select(SDOperand N) {
BuildMI(BB, X86::MOV32rr, 1, X86::EAX).addReg(Tmp1);
BuildMI(BB, X86::MOV32rr, 1, X86::EDX).addReg(Tmp2);
// Declare that EAX & EDX are live on exit.
BuildMI(BB, X86::IMPLICIT_USE, 3).addReg(X86::EAX).addReg(X86::EDX)
.addReg(X86::ESP);
break;
case 2:
if (getRegPressure(N.getOperand(0)) > getRegPressure(N.getOperand(1))) {
@ -2945,12 +2962,9 @@ void ISel::Select(SDOperand N) {
default: assert(0 && "All other types should have been promoted!!");
case MVT::f64:
BuildMI(BB, X86::FpSETRESULT, 1).addReg(Tmp1);
// Declare that top-of-stack is live on exit
BuildMI(BB, X86::IMPLICIT_USE, 2).addReg(X86::ST0).addReg(X86::ESP);
break;
case MVT::i32:
BuildMI(BB, X86::MOV32rr, 1, X86::EAX).addReg(Tmp1);
BuildMI(BB, X86::IMPLICIT_USE, 2).addReg(X86::EAX).addReg(X86::ESP);
break;
}
break;

29
llvm/lib/Target/X86/X86ISelSimple.cpp
View File

@ -618,7 +618,8 @@ void X86ISel::LoadArgumentsToVirtualRegs(Function &Fn) {
unsigned ArgOffset = 0; // Frame mechanisms handle retaddr slot
MachineFrameInfo *MFI = F->getFrameInfo();
for (Function::arg_iterator I = Fn.arg_begin(), E = Fn.arg_end(); I != E; ++I) {
for (Function::arg_iterator I = Fn.arg_begin(), E = Fn.arg_end();
I != E; ++I) {
bool ArgLive = !I->use_empty();
unsigned Reg = ArgLive ? getReg(*I) : 0;
int FI; // Frame object index
@ -676,6 +677,25 @@ void X86ISel::LoadArgumentsToVirtualRegs(Function &Fn) {
// llvm.va_start.
if (Fn.getFunctionType()->isVarArg())
VarArgsFrameIndex = MFI->CreateFixedObject(1, ArgOffset);
// Finally, inform the compiler what our live-outs will be, aka, what we will
// be returning in registers.
if (Fn.getReturnType() != Type::VoidTy)
switch (getClassB(Fn.getReturnType())) {
default: assert(0 && "Unknown type!");
case cByte:
case cShort:
case cInt:
F->addLiveOut(X86::EAX);
break;
case cLong:
F->addLiveOut(X86::EAX);
F->addLiveOut(X86::EDX);
break;
case cFP:
F->addLiveOut(X86::ST0);
break;
}
}
/// EmitSpecialCodeForMain - Emit any code that needs to be executed only in
@ -1434,23 +1454,16 @@ void X86ISel::visitReturnInst(ReturnInst &I) {
case cShort:
case cInt:
promote32(X86::EAX, ValueRecord(RetVal));
// Declare that EAX is live on exit
BuildMI(BB, X86::IMPLICIT_USE, 2).addReg(X86::EAX).addReg(X86::ESP);
break;
case cFP: { // Floats & Doubles: Return in ST(0)
unsigned RetReg = getReg(RetVal);
BuildMI(BB, X86::FpSETRESULT, 1).addReg(RetReg);
// Declare that top-of-stack is live on exit
BuildMI(BB, X86::IMPLICIT_USE, 2).addReg(X86::ST0).addReg(X86::ESP);
break;
}
case cLong: {
unsigned RetReg = getReg(RetVal);
BuildMI(BB, X86::MOV32rr, 1, X86::EAX).addReg(RetReg);
BuildMI(BB, X86::MOV32rr, 1, X86::EDX).addReg(RetReg+1);
// Declare that EAX & EDX are live on exit
BuildMI(BB, X86::IMPLICIT_USE, 3).addReg(X86::EAX).addReg(X86::EDX)
.addReg(X86::ESP);
break;
}
default: