commit 1144af3c9b4da48cd581156e05b24261c8de366a
author Richard Smith <richard-llvm@metafoo.co.uk> Fri Aug 24 23:29:28 2012 +0000
committer Richard Smith <richard-llvm@metafoo.co.uk> Fri Aug 24 23:29:28 2012 +0000
tree 49da576a97bfdab702528643450798baa54c790f
parent cac59d8ae815596f4f6b77d1a5414c0591168ea5

Fix integer undefined behavior due to signed left shift overflow in LLVM.
Reviewed offline by chandlerc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162623 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/CellSPU/SPUISelDAGToDAG.cpp

diff --git a/lib/Target/CellSPU/SPUISelDAGToDAG.cpp b/lib/Target/CellSPU/SPUISelDAGToDAG.cpp
index c27caea..425371d 100644
--- a/lib/Target/CellSPU/SPUISelDAGToDAG.cpp
+++ b/lib/Target/CellSPU/SPUISelDAGToDAG.cpp
@@ -83,12 +83,10 @@
       return true;
     } else if (vt == MVT::i32) {
       int32_t i_val = (int32_t) CN->getZExtValue();
-      short s_val = (short) i_val;
-      return i_val == s_val;
+      return i_val == SignExtend32<16>(i_val);
     } else {
       int64_t i_val = (int64_t) CN->getZExtValue();
-      short s_val = (short) i_val;
-      return i_val == s_val;
+      return i_val == SignExtend64<16>(i_val);
     }
   }
 
@@ -99,9 +97,10 @@
     EVT vt = FPN->getValueType(0);
     if (vt == MVT::f32) {
       int val = FloatToBits(FPN->getValueAPF().convertToFloat());
-      int sval = (int) ((val << 16) >> 16);
-      Imm = (short) val;
-      return val == sval;
+      if (val == SignExtend32<16>(val)) {
+        Imm = (short) val;
+        return true;
+      }
     }
 
     return false;