Restrict machine cse to really trivial coalescing. Leave the heavy lifting to a real coalescer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98007 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineCSE.cpp b/lib/CodeGen/MachineCSE.cpp
index b376e3d..ce8ebbc 100644
--- a/lib/CodeGen/MachineCSE.cpp
+++ b/lib/CodeGen/MachineCSE.cpp
@@ -91,7 +91,10 @@
unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
if (TII->isMoveInstr(*DefMI, SrcReg, DstReg, SrcSubIdx, DstSubIdx) &&
TargetRegisterInfo::isVirtualRegister(SrcReg) &&
+ MRI->getRegClass(SrcReg) == MRI->getRegClass(Reg) &&
!SrcSubIdx && !DstSubIdx) {
+ DEBUG(dbgs() << "Coalescing: " << *DefMI);
+ DEBUG(dbgs() << "*** to: " << *MI);
MO.setReg(SrcReg);
DefMI->eraseFromParent();
++NumCoalesces;