[llvm] r272835 - [X86]: Fix for uninitialized access introduced in r272797.

[Kevin B. Smith via llvm-commits]

Author: kbsmith1
Date: Wed Jun 15 15:52:19 2016
New Revision: 272835

URL: http://llvm.org/viewvc/llvm-project?rev=272835&view=rev
Log:
[X86]: Fix for uninitialized access introduced in r272797.

Modified:
    llvm/trunk/lib/Target/X86/X86FixupBWInsts.cpp

Modified: llvm/trunk/lib/Target/X86/X86FixupBWInsts.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86FixupBWInsts.cpp?rev=272835&r1=272834&r2=272835&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86FixupBWInsts.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86FixupBWInsts.cpp Wed Jun 15 15:52:19 2016
@@ -372,12 +372,16 @@ void FixupBWInstPass::processBasicBlock(
     LiveRegs.addLiveIns(MBB);
 
     auto NextCandidateIter = MIReplacements.begin();
+    auto EndCandidateIter = MIReplacements.end();
 
     for (auto I = MBB.begin(); I != MBB.end(); ++I) {
       MachineInstr *MI = &*I;
       SmallVector<std::pair<unsigned, const MachineOperand*>, 4> Clobbers;
       LiveRegs.stepForward(*MI, Clobbers);
 
+      if (NextCandidateIter == EndCandidateIter)
+        break;
+
       // Only check and create a new instruction if this instruction is
       // known to be a candidate that didn't get transformed.
       if (NextCandidateIter->first == MI) {