X86: Remove pre-2010 dead code in mergeSPUpdatesDown

llvm-svn: 230075
This commit is contained in:
Reid Kleckner 2015-02-20 22:13:25 +00:00
parent b7875837c7
commit 8142a08ce7
1 changed files with 0 additions and 36 deletions

View File

@ -312,38 +312,6 @@ void mergeSPUpdatesUp(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
}
}
/// mergeSPUpdatesDown - Merge two stack-manipulating instructions lower
/// iterator.
static
void mergeSPUpdatesDown(MachineBasicBlock &MBB,
MachineBasicBlock::iterator &MBBI,
unsigned StackPtr, uint64_t *NumBytes = nullptr) {
// FIXME: THIS ISN'T RUN!!!
return;
if (MBBI == MBB.end()) return;
MachineBasicBlock::iterator NI = std::next(MBBI);
if (NI == MBB.end()) return;
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;
}
}
/// mergeSPUpdates - Checks the instruction before/after the passed
/// instruction. If it is an ADD/SUB/LEA instruction it is deleted argument and
/// the stack adjustment is returned as a positive value for ADD/LEA and a
@ -823,10 +791,6 @@ void X86FrameLowering::emitPrologue(MachineFunction &MF) const {
// the callee has more arguments then the caller.
NumBytes -= mergeSPUpdates(MBB, MBBI, StackPtr, true);
// If there is an ADD32ri or SUB32ri of ESP immediately after this
// instruction, merge the two instructions.
mergeSPUpdatesDown(MBB, MBBI, StackPtr, &NumBytes);
// Adjust stack pointer: ESP -= numbytes.
// Windows and cygwin/mingw require a prologue helper routine when allocating