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authorLang Hames <lhames@gmail.com>2009-05-11 23:14:13 +0000
committerLang Hames <lhames@gmail.com>2009-05-11 23:14:13 +0000
commit36bec3239dced2c84f447b4e6bc78c67d2c11779 (patch)
treebdfaa86ed6426fedfbcdaf970ed9e7126c5fb278 /lib/CodeGen/SimpleRegisterCoalescing.cpp
parent56cfcd7b81fd45eae68c8b40a058b41a79640fe8 (diff)
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Fixed PR4090.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71495 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/SimpleRegisterCoalescing.cpp')
-rw-r--r--lib/CodeGen/SimpleRegisterCoalescing.cpp17
1 files changed, 16 insertions, 1 deletions
diff --git a/lib/CodeGen/SimpleRegisterCoalescing.cpp b/lib/CodeGen/SimpleRegisterCoalescing.cpp
index 9d1297b..a7807f1 100644
--- a/lib/CodeGen/SimpleRegisterCoalescing.cpp
+++ b/lib/CodeGen/SimpleRegisterCoalescing.cpp
@@ -608,14 +608,29 @@ bool SimpleRegisterCoalescing::ReMaterializeTrivialDef(LiveInterval &SrcInt,
// If copy kills the source register, find the last use and propagate
// kill.
+ bool checkForDeadDef = false;
MachineBasicBlock *MBB = CopyMI->getParent();
if (CopyMI->killsRegister(SrcInt.reg))
- TrimLiveIntervalToLastUse(CopyIdx, MBB, SrcInt, SrcLR);
+ if (!TrimLiveIntervalToLastUse(CopyIdx, MBB, SrcInt, SrcLR)) {
+ checkForDeadDef = true;
+ }
MachineBasicBlock::iterator MII = next(MachineBasicBlock::iterator(CopyMI));
CopyMI->removeFromParent();
tii_->reMaterialize(*MBB, MII, DstReg, DefMI);
MachineInstr *NewMI = prior(MII);
+
+ if (checkForDeadDef) {
+ // PR4090 fix: Trim interval failed because there was no use of the
+ // source interval in this MBB. If the def is in this MBB too then we
+ // should mark it dead:
+ if (DefMI->getParent() == MBB) {
+ DefMI->addRegisterDead(SrcInt.reg, tri_);
+ SrcLR->end = SrcLR->start + 1;
+ }
+
+ }
+
// CopyMI may have implicit operands, transfer them over to the newly
// rematerialized instruction. And update implicit def interval valnos.
for (unsigned i = CopyMI->getDesc().getNumOperands(),