Fix the problems with callee popped argument lists

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21988 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2005-05-13 22:13:49 +00:00
parent 678cfa9b19
commit 06cebb456a

View File

@ -3746,7 +3746,43 @@ void ISel::Select(SDOperand N) {
// Amount the callee added to the stack pointer.
Tmp2 = cast<ConstantSDNode>(N.getOperand(2))->getValue();
BuildMI(BB, X86::ADJCALLSTACKUP, 2).addImm(Tmp1).addImm(Tmp2);
// This hackery is due to the fact that we don't want to emit this code:
// call foo
// mov vreg, EAX
// adjcallstackup
//
// Because if foo is a fastcc call and if vreg gets spilled, we might end up
// with this:
// call foo
// mov [ESP+offset], EAX ;; Offset doesn't consider the 12!
// sub ESP, 12
//
// To avoid this, we force the adjcallstackup instruction before the 0, 1 or
// 2 moves that occur after the call. The correct way to fix this is to use
// target-specific DAG nodes in the call sequence. FIXME!
//
if (EnableFastCC) {
// This code should be safe. Be defensive for LLVM 1.5 release though.
assert(!BB->empty());
MachineBasicBlock::iterator PrevI = --BB->end();
if (PrevI->getOpcode() == X86::CALLpcrel32 ||
PrevI->getOpcode() == X86::CALL32r)
++PrevI;
else if (PrevI != BB->begin() &&
((--PrevI)->getOpcode() == X86::CALLpcrel32 ||
PrevI->getOpcode() == X86::CALL32r))
++PrevI;
else if (PrevI != BB->begin() &&
((--PrevI)->getOpcode() == X86::CALLpcrel32 ||
PrevI->getOpcode() == X86::CALL32r))
++PrevI;
else
PrevI = BB->end();
BuildMI(*BB, PrevI, X86::ADJCALLSTACKUP, 2).addImm(Tmp1).addImm(Tmp2);
} else {
BuildMI(*BB, PrevI, X86::ADJCALLSTACKUP, 2).addImm(Tmp1).addImm(Tmp2);
}
return;
case ISD::MEMSET: {
Select(N.getOperand(0)); // Select the chain.