target/s390x: Skip wout, cout helpers if op helper does not return

When op raises an exception, it may not have initialized the output
temps that would be written back by wout or cout.

Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

diff --git a/target/s390x/translate.c b/target/s390x/translate.c
index 18861cd1862dc745d074a719e952abd46b4c1548..a7bd689337f18f1b06c84207875233dd122ca654 100644 (file)
--- a/target/s390x/translate.c
+++ b/target/s390x/translate.c
@@ -1128,11 +1128,19 @@ struct DisasInsn {
 
     const char *name;
 
+    /* Pre-process arguments before HELP_OP.  */
     void (*help_in1)(DisasContext *, DisasFields *, DisasOps *);
     void (*help_in2)(DisasContext *, DisasFields *, DisasOps *);
     void (*help_prep)(DisasContext *, DisasFields *, DisasOps *);
+
+    /*
+     * Post-process output after HELP_OP.
+     * Note that these are not called if HELP_OP returns DISAS_NORETURN.
+     */
     void (*help_wout)(DisasContext *, DisasFields *, DisasOps *);
     void (*help_cout)(DisasContext *, DisasOps *);
+
+    /* Implement the operation itself.  */
     DisasJumpType (*help_op)(DisasContext *, DisasOps *);
 
     uint64_t data;
@@ -6125,11 +6133,13 @@ static DisasJumpType translate_one(CPUS390XState *env, DisasContext *s)
     if (insn->help_op) {
         ret = insn->help_op(s, &o);
     }
-    if (insn->help_wout) {
-        insn->help_wout(s, &f, &o);
-    }
-    if (insn->help_cout) {
-        insn->help_cout(s, &o);
+    if (ret != DISAS_NORETURN) {
+        if (insn->help_wout) {
+            insn->help_wout(s, &f, &o);
+        }
+        if (insn->help_cout) {
+            insn->help_cout(s, &o);
+        }
     }
 
     /* Free any temporaries created by the helpers.  */