[APInt] Add clearSignBit method. Use it and setSignBit in a few places. NFCI

llvm-svn: 301656

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index d3b462e08b4..60970775de6 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -190,8 +190,8 @@ static void computeSignedMinMaxValuesFromKnownBits(const KnownBits &Known,
   Max = Known.One|UnknownBits;
 
   if (UnknownBits.isNegative()) { // Sign bit is unknown
-    Min.setBit(Min.getBitWidth()-1);
-    Max.clearBit(Max.getBitWidth()-1);
+    Min.setSignBit();
+    Max.clearSignBit();
   }
 }