If deleting a reload instruction due to reuse (value is available in register R and reload is targeting R), make sure to invalidate the kill information of the last kill.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44894 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2007-12-11 23:36:57 +00:00
parent efe2be7976
commit 39c883cfc5

View File

@ -474,6 +474,17 @@ static void InvalidateKills(MachineInstr &MI, BitVector &RegKills,
}
}
/// InvalidateKill - A MI that defines the specified register is being deleted,
/// invalidate the register kill information.
static void InvalidateKill(unsigned Reg, BitVector &RegKills,
std::vector<MachineOperand*> &KillOps) {
if (RegKills[Reg]) {
KillOps[Reg]->unsetIsKill();
KillOps[Reg] = NULL;
RegKills.reset(Reg);
}
}
/// InvalidateRegDef - If the def operand of the specified def MI is now dead
/// (since it's spill instruction is removed), mark it isDead. Also checks if
/// the def MI has other definition operands that are not dead. Returns it by
@ -537,12 +548,13 @@ static void UpdateKills(MachineInstr &MI, BitVector &RegKills,
// That can't be right. Register is killed but not re-defined and it's
// being reused. Let's fix that.
KillOps[Reg]->unsetIsKill();
KillOps[Reg] = NULL;
RegKills.reset(Reg);
if (i < TID->numOperands &&
TID->getOperandConstraint(i, TOI::TIED_TO) == -1)
// Unless it's a two-address operand, this is the new kill.
MO.setIsKill();
}
if (MO.isKill()) {
RegKills.set(Reg);
KillOps[Reg] = &MO;
@ -1261,8 +1273,11 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM) {
NextMII = &MI;
--NextMII; // backtrack to the copy.
BackTracked = true;
} else
} else {
DOUT << "Removing now-noop copy: " << MI;
// Unset last kill since it's being reused.
InvalidateKill(InReg, RegKills, KillOps);
}
VRM.RemoveMachineInstrFromMaps(&MI);
MBB.erase(&MI);
@ -1298,6 +1313,7 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM) {
// the value and there isn't an earlier def that has already clobbered the
// physreg.
if (PhysReg &&
!TII->isStoreToStackSlot(&MI, SS) && // Not profitable!
DeadStore->findRegisterUseOperandIdx(PhysReg, true) != -1 &&
MRI->unfoldMemoryOperand(MF, &MI, PhysReg, false, true, NewMIs)) {
MBB.insert(MII, NewMIs[0]);