[llvm-commits] [llvm] r110241 - /llvm/trunk/lib/Analysis/ScalarEvolution.cpp

[Dan Gohman]

Author: djg
Date: Wed Aug  4 14:52:50 2010
New Revision: 110241

URL: http://llvm.org/viewvc/llvm-project?rev=110241&view=rev
Log:
Fix a minor bug which resulted in intermediate calculations
using wider types than are necessary.

Modified:
    llvm/trunk/lib/Analysis/ScalarEvolution.cpp

Modified: llvm/trunk/lib/Analysis/ScalarEvolution.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ScalarEvolution.cpp?rev=110241&r1=110240&r2=110241&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/ScalarEvolution.cpp (original)
+++ llvm/trunk/lib/Analysis/ScalarEvolution.cpp Wed Aug  4 14:52:50 2010
@@ -1896,7 +1896,7 @@
       // TODO: Generalize this to non-constants by using known-bits information.
       const Type *Ty = LHS->getType();
       unsigned LZ = RHSC->getValue()->getValue().countLeadingZeros();
-      unsigned MaxShiftAmt = getTypeSizeInBits(Ty) - LZ;
+      unsigned MaxShiftAmt = getTypeSizeInBits(Ty) - LZ - 1;
       // For non-power-of-two values, effectively round the value up to the
       // nearest power of two.
       if (!RHSC->getValue()->getValue().isPowerOf2())