From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Mon, 17 Nov 2014 17:43:27 +0000 (+0000)
Subject: Avoid undefined behavior by masking the shift amount.
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f70c673db75b71756251e5647e7714ecd345340c;p=platform%2Fupstream%2Fllvm.git

Avoid undefined behavior by masking the shift amount.

Should hopefully fix the mips bots.

llvm-svn: 222146
---

diff --git a/llvm/include/llvm/Bitcode/BitstreamReader.h b/llvm/include/llvm/Bitcode/BitstreamReader.h
index a4d2b1d..d6f085c 100644
--- a/llvm/include/llvm/Bitcode/BitstreamReader.h
+++ b/llvm/include/llvm/Bitcode/BitstreamReader.h
@@ -345,7 +345,7 @@ public:
 
     // If the field is fully contained by CurWord, return it quickly.
     if (BitsInCurWord >= NumBits) {
-      word_t R = CurWord & ((word_t(1) << NumBits) - 1);
+      word_t R = CurWord & ((word_t(1) << (NumBits & Mask)) - 1);
 
       // Use a mask to avoid undefined behavior.
       CurWord >>= (NumBits & Mask);
@@ -363,7 +363,7 @@ public:
     if (BitsLeft > BitsInCurWord)
       return 0;
 
-    word_t R2 = CurWord & ((word_t(1) << BitsLeft) - 1);
+    word_t R2 = CurWord & ((word_t(1) << (BitsLeft & Mask)) - 1);
 
     // Use a mask to avoid undefined behavior.
     CurWord >>= (BitsLeft & Mask);