commit d1d90974d5239151892742b11dd26cf12055aade
Author: cborntra <cborntra@8f6e269a-dfd6-0310-a8e1-e2731360e62c>
Date:   Thu Feb 5 11:05:10 2015 +0000

    Fix bug 343802. We need to handle one more special case in the spechelper
    
    
    git-svn-id: svn://svn.valgrind.org/vex/trunk@3083 8f6e269a-dfd6-0310-a8e1-e2731360e62c

diff --git a/VEX/priv/guest_s390_helpers.c b/VEX/priv/guest_s390_helpers.c
index 78ca2ef..df1f24b 100644
--- a/VEX/priv/guest_s390_helpers.c
+++ b/VEX/priv/guest_s390_helpers.c
@@ -1958,7 +1958,10 @@ guest_s390x_spechelper(const HChar *function_name, IRExpr **args,
             return unop(Iop_1Uto32, binop(Iop_CmpNE64, cc_dep1, mkU64(0)));
          }
          if (cond == 4 || cond == 4 + 1) {
-            return unop(Iop_1Uto32, binop(Iop_CmpLT64S, cc_dep1, mkU64(0)));
+             /* Special case cc_dep < 0. Only check the MSB to avoid bogus
+               memcheck complaints due to gcc magic. Fixes 343802
+             */
+            return unop(Iop_64to32, binop(Iop_Shr64, cc_dep1, mkU8(63)));
          }
          if (cond == 8 + 4 || cond == 8 + 4 + 1) {
             return unop(Iop_1Uto32, binop(Iop_CmpLE64S, cc_dep1, mkU64(0)));