From: Alexey Samsonov <vonosmas@gmail.com>
Date: Wed, 20 Aug 2014 21:22:03 +0000 (+0000)
Subject: Fix undefined behavior (left shift of negative value) in Hexagon backend.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=145d28e73b6b70c1b4ef04ac8448646ead7a03b3;p=llvm

Fix undefined behavior (left shift of negative value) in Hexagon backend.

This bug is reported by UBSan.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216125 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/Hexagon/HexagonInstrInfo.cpp b/lib/Target/Hexagon/HexagonInstrInfo.cpp
index 41de8489ed8..a63e3826f07 100644
--- a/lib/Target/Hexagon/HexagonInstrInfo.cpp
+++ b/lib/Target/Hexagon/HexagonInstrInfo.cpp
@@ -1766,7 +1766,7 @@ int HexagonInstrInfo::getMinValue(const MachineInstr *MI) const {
                     & HexagonII::ExtentBitsMask;
 
   if (isSigned) // if value is signed
-    return -1 << (bits - 1);
+    return -1U << (bits - 1);
   else
     return 0;
 }
@@ -1780,9 +1780,9 @@ int HexagonInstrInfo::getMaxValue(const MachineInstr *MI) const {
                     & HexagonII::ExtentBitsMask;
 
   if (isSigned) // if value is signed
-    return ~(-1 << (bits - 1));
+    return ~(-1U << (bits - 1));
   else
-    return ~(-1 << bits);
+    return ~(-1U << bits);
 }
 
 // Returns true if an instruction can be converted into a non-extended
diff --git a/lib/Target/Hexagon/MCTargetDesc/HexagonMCInst.cpp b/lib/Target/Hexagon/MCTargetDesc/HexagonMCInst.cpp
index 98b8db07638..c842b9b7cf3 100644
--- a/lib/Target/Hexagon/MCTargetDesc/HexagonMCInst.cpp
+++ b/lib/Target/Hexagon/MCTargetDesc/HexagonMCInst.cpp
@@ -155,7 +155,7 @@ int HexagonMCInst::getMinValue(void) const {
                     & HexagonII::ExtentBitsMask;
 
   if (isSigned) // if value is signed
-    return -1 << (bits - 1);
+    return -1U << (bits - 1);
   else
     return 0;
 }
@@ -170,7 +170,7 @@ int HexagonMCInst::getMaxValue(void) const {
                     & HexagonII::ExtentBitsMask;
 
   if (isSigned) // if value is signed
-    return ~(-1 << (bits - 1));
+    return ~(-1U << (bits - 1));
   else
-    return ~(-1 << bits);
+    return ~(-1U << bits);
 }