6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-07-29 10:25:12 +00:00
Code Issues Projects Releases Wiki Activity

Yet another nasty spiller bug.

Browse Source 
%ecx = op
store %cl<kill>, (addr)
(addr) = op %al

It's not safe to unfold the last operand and eliminate store even though %cl is marked kill. It's a sub-register use which means one of its super-register(s) may be used below.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50794 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng
2008-05-07 00:49:28 +00:00
parent 42ac929ed9
commit 7ebc06bfd8
2 changed files with 56 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

33
lib/CodeGen/VirtRegMap.cpp
View File

@@ -1465,20 +1465,25 @@ 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->killsRegister(PhysReg) &&
TII->unfoldMemoryOperand(MF, &MI, PhysReg, false, true, NewMIs)) {
MBB.insert(MII, NewMIs[0]);
NewStore = NewMIs[1];
MBB.insert(MII, NewStore);
VRM.addSpillSlotUse(SS, NewStore);
VRM.RemoveMachineInstrFromMaps(&MI);
MBB.erase(&MI);
Erased = true;
--NextMII;
--NextMII; // backtrack to the unfolded instruction.
BackTracked = true;
isDead = true;
!TII->isStoreToStackSlot(&MI, SS)) { // Not profitable!
MachineOperand *KillOpnd =
DeadStore->findRegisterUseOperand(PhysReg, true);
// Note, if the store is storing a sub-register, it's possible the
// super-register is needed below.
if (KillOpnd && !KillOpnd->getSubReg() &&
TII->unfoldMemoryOperand(MF, &MI, PhysReg, false, true,NewMIs)){
MBB.insert(MII, NewMIs[0]);
NewStore = NewMIs[1];
MBB.insert(MII, NewStore);
VRM.addSpillSlotUse(SS, NewStore);
VRM.RemoveMachineInstrFromMaps(&MI);
MBB.erase(&MI);
Erased = true;
--NextMII;
--NextMII; // backtrack to the unfolded instruction.
BackTracked = true;
isDead = true;
}
}
}