Also update sub-register intervals after a trivial computation is rematt'ed for a copy instruction. PR2775.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57458 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SimpleRegisterCoalescing.cpp b/lib/CodeGen/SimpleRegisterCoalescing.cpp
index bb860d2..2f2d549 100644
--- a/lib/CodeGen/SimpleRegisterCoalescing.cpp
+++ b/lib/CodeGen/SimpleRegisterCoalescing.cpp
@@ -460,6 +460,16 @@
unsigned DefIdx = li_->getDefIndex(CopyIdx);
const LiveRange *DLR= li_->getInterval(DstReg).getLiveRangeContaining(DefIdx);
DLR->valno->copy = NULL;
+ // Don't forget to update sub-register intervals.
+ if (TargetRegisterInfo::isPhysicalRegister(DstReg)) {
+ for (const unsigned* SR = tri_->getSubRegisters(DstReg); *SR; ++SR) {
+ if (!li_->hasInterval(*SR))
+ continue;
+ DLR = li_->getInterval(*SR).getLiveRangeContaining(DefIdx);
+ if (DLR && DLR->valno->copy == CopyMI)
+ DLR->valno->copy = NULL;
+ }
+ }
MachineBasicBlock::iterator MII = CopyMI;
MachineBasicBlock *MBB = CopyMI->getParent();