[llvm-commits] [llvm] r161269 - /llvm/trunk/lib/CodeGen/RegisterCoalescer.cpp

[Jakob Stoklund Olesen]

Author: stoklund
Date: Fri Aug  3 17:12:51 2012
New Revision: 161269

URL: http://llvm.org/viewvc/llvm-project?rev=161269&view=rev
Log:
Delete merged physreg copies in joinReservedPhysReg().

Previously, the identity copy would survive through register allocation
before it was removed by the rewriter.

Modified:
    llvm/trunk/lib/CodeGen/RegisterCoalescer.cpp

Modified: llvm/trunk/lib/CodeGen/RegisterCoalescer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/RegisterCoalescer.cpp?rev=161269&r1=161268&r2=161269&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/RegisterCoalescer.cpp (original)
+++ llvm/trunk/lib/CodeGen/RegisterCoalescer.cpp Fri Aug  3 17:12:51 2012
@@ -1091,6 +1091,11 @@
   // register live range doesn't need to be accurate as long as all the
   // defs are there.
 
+  // Delete the identity copy.
+  MachineInstr *CopyMI = MRI->getVRegDef(RHS.reg);
+  LIS->RemoveMachineInstrFromMaps(CopyMI);
+  CopyMI->eraseFromParent();
+
   // We don't track kills for reserved registers.
   MRI->clearKillFlags(CP.getSrcReg());