[llvm] r233881 - Fix a bug indicated by -fsanitize=shift-exponent.

[Alexey Samsonov]

Author: samsonov
Date: Wed Apr  1 20:30:10 2015
New Revision: 233881

URL: http://llvm.org/viewvc/llvm-project?rev=233881&view=rev
Log:
Fix a bug indicated by -fsanitize=shift-exponent.

Modified:
    llvm/trunk/lib/Transforms/Utils/LoopUnrollRuntime.cpp

Modified: llvm/trunk/lib/Transforms/Utils/LoopUnrollRuntime.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/LoopUnrollRuntime.cpp?rev=233881&r1=233880&r2=233881&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/LoopUnrollRuntime.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/LoopUnrollRuntime.cpp Wed Apr  1 20:30:10 2015
@@ -320,7 +320,7 @@ bool llvm::UnrollRuntimeLoopProlog(Loop
   // This constraint lets us deal with an overflowing trip count easily; see the
   // comment on ModVal below.  This check is equivalent to `Log2(Count) <
   // BEWidth`.
-  if (static_cast<uint64_t>(Count) > (1ULL << BEWidth))
+  if (BEWidth < 64 && static_cast<uint64_t>(Count) > (1ULL << BEWidth))
     return false;
 
   // If this loop is nested, then the loop unroller changes the code in