[llvm-commits] [llvm] r71769 - /llvm/trunk/lib/CodeGen/TwoAddressInstructionPass.cpp

[Lang Hames]

Author: lhames
Date: Wed May 13 23:26:30 2009
New Revision: 71769

URL: http://llvm.org/viewvc/llvm-project?rev=71769&view=rev
Log:
Fix for PR4124. Make TwoAddressFormPass::FindLastUseInMBB return the real last use.

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

Modified: llvm/trunk/lib/CodeGen/TwoAddressInstructionPass.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/TwoAddressInstructionPass.cpp?rev=71769&r1=71768&r2=71769&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/TwoAddressInstructionPass.cpp (original)
+++ llvm/trunk/lib/CodeGen/TwoAddressInstructionPass.cpp Wed May 13 23:26:30 2009
@@ -316,7 +316,7 @@
 MachineInstr *TwoAddressInstructionPass::FindLastUseInMBB(unsigned Reg,
                                                          MachineBasicBlock *MBB,
                                                          unsigned Dist) {
-  unsigned LastUseDist = Dist;
+  unsigned LastUseDist = 0;
   MachineInstr *LastUse = 0;
   for (MachineRegisterInfo::reg_iterator I = MRI->reg_begin(Reg),
          E = MRI->reg_end(); I != E; ++I) {
@@ -327,7 +327,10 @@
     DenseMap<MachineInstr*, unsigned>::iterator DI = DistanceMap.find(MI);
     if (DI == DistanceMap.end())
       continue;
-    if (MO.isUse() && DI->second < LastUseDist) {
+    if (DI->second >= Dist)
+      continue;
+
+    if (MO.isUse() && DI->second > LastUseDist) {
       LastUse = DI->first;
       LastUseDist = DI->second;
     }