Preserve implicit defs in ARMLoadStoreOptimizer.
When a number of sub-register VLRDS instructions are combined into a
VLDM, preserve any super-register implicit defs. This is required to
keep the register scavenger and machine code verifier happy.
Enable machine code verification after ARMLoadStoreOptimizer.
ARM/2012-01-26-CopyPropKills.ll was failing because of this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153610 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
index 51dfa65..f75ac90 100644
--- a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
+++ b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
@@ -93,7 +93,9 @@
bool MergeOps(MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI,
int Offset, unsigned Base, bool BaseKill, int Opcode,
ARMCC::CondCodes Pred, unsigned PredReg, unsigned Scratch,
- DebugLoc dl, SmallVector<std::pair<unsigned, bool>, 8> &Regs);
+ DebugLoc dl,
+ ArrayRef<std::pair<unsigned, bool> > Regs,
+ ArrayRef<unsigned> ImpDefs);
void MergeOpsUpdate(MachineBasicBlock &MBB,
MemOpQueue &MemOps,
unsigned memOpsBegin,
@@ -282,7 +284,8 @@
int Offset, unsigned Base, bool BaseKill,
int Opcode, ARMCC::CondCodes Pred,
unsigned PredReg, unsigned Scratch, DebugLoc dl,
- SmallVector<std::pair<unsigned, bool>, 8> &Regs) {
+ ArrayRef<std::pair<unsigned, bool> > Regs,
+ ArrayRef<unsigned> ImpDefs) {
// Only a single register to load / store. Don't bother.
unsigned NumRegs = Regs.size();
if (NumRegs <= 1)
@@ -350,6 +353,10 @@
MIB = MIB.addReg(Regs[i].first, getDefRegState(isDef)
| getKillRegState(Regs[i].second));
+ // Add implicit defs for super-registers.
+ for (unsigned i = 0, e = ImpDefs.size(); i != e; ++i)
+ MIB.addReg(ImpDefs[i], RegState::ImplicitDefine);
+
return true;
}
@@ -384,19 +391,29 @@
}
SmallVector<std::pair<unsigned, bool>, 8> Regs;
+ SmallVector<unsigned, 8> ImpDefs;
for (unsigned i = memOpsBegin; i < memOpsEnd; ++i) {
unsigned Reg = memOps[i].Reg;
// If we are inserting the merged operation after an operation that
// uses the same register, make sure to transfer any kill flag.
bool isKill = memOps[i].isKill || KilledRegs.count(Reg);
Regs.push_back(std::make_pair(Reg, isKill));
+
+ // Collect any implicit defs of super-registers. They must be preserved.
+ for (MIOperands MO(memOps[i].MBBI); MO.isValid(); ++MO) {
+ if (!MO->isReg() || !MO->isDef() || !MO->isImplicit() || MO->isDead())
+ continue;
+ unsigned DefReg = MO->getReg();
+ if (std::find(ImpDefs.begin(), ImpDefs.end(), DefReg) == ImpDefs.end())
+ ImpDefs.push_back(DefReg);
+ }
}
// Try to do the merge.
MachineBasicBlock::iterator Loc = memOps[insertAfter].MBBI;
++Loc;
if (!MergeOps(MBB, Loc, Offset, Base, BaseKill, Opcode,
- Pred, PredReg, Scratch, dl, Regs))
+ Pred, PredReg, Scratch, dl, Regs, ImpDefs))
return;
// Merge succeeded, update records.