Oops, I really wanted to commit this part also :)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42700 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Anton Korobeynikov 2007-10-06 16:39:43 +00:00
parent 4f1c33f7c8
commit 2508372746

View File

@ -1500,6 +1500,31 @@ void mergeSPUpdatesUp(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
}
}
// mergeSPUpdatesUp - Merge two stack-manipulating instructions lower iterator.
static
void mergeSPUpdatesDown(MachineBasicBlock &MBB,MachineBasicBlock::iterator &MBBI,
unsigned StackPtr, uint64_t *NumBytes = NULL) {
if (MBBI != MBB.end()) {
MachineBasicBlock::iterator NI = next(MBBI);
unsigned Opc = NI->getOpcode();
if ((Opc == X86::ADD64ri32 || Opc == X86::ADD64ri8 ||
Opc == X86::ADD32ri || Opc == X86::ADD32ri8) &&
NI->getOperand(0).getReg() == StackPtr) {
if (NumBytes)
*NumBytes -= NI->getOperand(2).getImm();
MBB.erase(NI);
MBBI = NI;
} else if ((Opc == X86::SUB64ri32 || Opc == X86::SUB64ri8 ||
Opc == X86::SUB32ri || Opc == X86::SUB32ri8) &&
NI->getOperand(0).getReg() == StackPtr) {
if (NumBytes)
*NumBytes += NI->getOperand(2).getImm();
MBB.erase(NI);
MBBI = NI;
}
}
}
void X86RegisterInfo::emitPrologue(MachineFunction &MF) const {
MachineBasicBlock &MBB = MF.front(); // Prolog goes in entry BB
MachineFrameInfo *MFI = MF.getFrameInfo();
@ -1585,9 +1610,9 @@ void X86RegisterInfo::emitPrologue(MachineFunction &MF) const {
MBB.insert(MBBI, MI);
}
} else {
// If there is an ADD32ri or SUB32ri of ESP immediately before this
// If there is an ADD32ri or SUB32ri of ESP immediately after this
// instruction, merge the two instructions.
mergeSPUpdatesUp(MBB, MBBI, StackPtr, &NumBytes);
mergeSPUpdatesDown(MBB, MBBI, StackPtr, &NumBytes);
if (NumBytes)
emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit, TII);