[llvm-commits] [llvm] r103679 - /llvm/trunk/lib/CodeGen/RegAllocLocal.cpp

[Evan Cheng]

Author: evancheng
Date: Wed May 12 18:59:42 2010
New Revision: 103679

URL: http://llvm.org/viewvc/llvm-project?rev=103679&view=rev
Log:
Do not attempt copy coalescing if the source and dest sub-register indices do not match.

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

Modified: llvm/trunk/lib/CodeGen/RegAllocLocal.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/RegAllocLocal.cpp?rev=103679&r1=103678&r2=103679&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/RegAllocLocal.cpp (original)
+++ llvm/trunk/lib/CodeGen/RegAllocLocal.cpp Wed May 12 18:59:42 2010
@@ -846,7 +846,8 @@
     unsigned SrcCopyReg, DstCopyReg, SrcCopySubReg, DstCopySubReg;
     unsigned SrcCopyPhysReg = 0U;
     bool isCopy = TII->isMoveInstr(*MI, SrcCopyReg, DstCopyReg, 
-                                   SrcCopySubReg, DstCopySubReg);
+                                   SrcCopySubReg, DstCopySubReg) &&
+      SrcCopySubReg == DstCopySubReg;
     if (isCopy && TargetRegisterInfo::isVirtualRegister(SrcCopyReg))
       SrcCopyPhysReg = getVirt2PhysRegMapSlot(SrcCopyReg);
 
@@ -1154,7 +1155,8 @@
     // the register scavenger.  See pr4100.)
     if (TII->isMoveInstr(*MI, SrcCopyReg, DstCopyReg,
                          SrcCopySubReg, DstCopySubReg) &&
-        SrcCopyReg == DstCopyReg && DeadDefs.empty())
+        SrcCopyReg == DstCopyReg && SrcCopySubReg == DstCopySubReg &&
+        DeadDefs.empty())
       MBB.erase(MI);
   }