From: Benjamin Kramer <benny.kra@googlemail.com>
Date: Mon, 28 Nov 2011 16:56:38 +0000 (+0000)
Subject: Handle more cases in APInt::getLowBitsSet's fast path.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=39a2eb7dea034820eb4b93b2361ae307b0cee5f2;p=oota-llvm.git

Handle more cases in APInt::getLowBitsSet's fast path.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145249 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/llvm/ADT/APInt.h b/include/llvm/ADT/APInt.h
index 707e0dbb6b9..78119bce2ac 100644
--- a/include/llvm/ADT/APInt.h
+++ b/include/llvm/ADT/APInt.h
@@ -497,8 +497,8 @@ public:
     if (loBitsSet == APINT_BITS_PER_WORD)
       return APInt(numBits, -1ULL);
     // For small values, return quickly.
-    if (numBits < APINT_BITS_PER_WORD)
-      return APInt(numBits, (1ULL << loBitsSet) - 1);
+    if (loBitsSet <= APINT_BITS_PER_WORD)
+      return APInt(numBits, -1ULL >> (APINT_BITS_PER_WORD - loBitsSet));
     return getAllOnesValue(numBits).lshr(numBits - loBitsSet);
   }