[llvm-commits] [llvm] r122108 - in /llvm/trunk: include/llvm/CodeGen/LiveInterval.h lib/CodeGen/LiveIntervalUnion.cpp

[Jakob Stoklund Olesen]

Author: stoklund
Date: Fri Dec 17 17:16:38 2010
New Revision: 122108

URL: http://llvm.org/viewvc/llvm-project?rev=122108&view=rev
Log:
Avoid dereferencing end() in collectInterferingVRegs() when there is no
interference.

Modified:
    llvm/trunk/include/llvm/CodeGen/LiveInterval.h
    llvm/trunk/lib/CodeGen/LiveIntervalUnion.cpp

Modified: llvm/trunk/include/llvm/CodeGen/LiveInterval.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/LiveInterval.h?rev=122108&r1=122107&r2=122108&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/LiveInterval.h (original)
+++ llvm/trunk/include/llvm/CodeGen/LiveInterval.h Fri Dec 17 17:16:38 2010
@@ -250,6 +250,7 @@
     /// position is in a hole, this method returns an iterator pointing to the
     /// LiveRange immediately after the hole.
     iterator advanceTo(iterator I, SlotIndex Pos) {
+      assert(I != end());
       if (Pos >= endIndex())
         return end();
       while (I->end <= Pos) ++I;

Modified: llvm/trunk/lib/CodeGen/LiveIntervalUnion.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/LiveIntervalUnion.cpp?rev=122108&r1=122107&r2=122108&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/LiveIntervalUnion.cpp (original)
+++ llvm/trunk/lib/CodeGen/LiveIntervalUnion.cpp Fri Dec 17 17:16:38 2010
@@ -238,7 +238,7 @@
   InterferenceResult IR = firstInterference();
   LiveInterval::iterator VirtRegEnd = VirtReg->end();
   LiveInterval *RecentInterferingVReg = NULL;
-  while (IR.LiveUnionI.valid()) {
+  if (IR.VirtRegI != VirtRegEnd) while (IR.LiveUnionI.valid()) {
     // Advance the union's iterator to reach an unseen interfering vreg.
     do {
       if (IR.LiveUnionI.value() == RecentInterferingVReg)