Re: [PATCH v2] target/s390x: Fix CC set by CONVERT TO FIXED/LOGICAL

[Richard Henderson]

On 6/28/21 9:35 AM, Ulrich Weigand wrote:
@@ -506,6 +534,7 @@ uint64_t HELPER(cgeb)(CPUS390XState *env, uint64_t v2, 
uint32_t m34)
  {
      int old_mode = s390_swap_bfp_rounding_mode(env, round_from_m34(m34));
      int64_t ret = float32_to_int64(v2, &env->fpu_status);
+    env->cc_op = set_cc_conv_f32(v2, &env->fpu_status);
  
      s390_restore_bfp_rounding_mode(env, old_mode);
      handle_exceptions(env, xxc_from_m34(m34), GETPC());

Don't you need to wait until after handle_exceptions, and the handling of suppressing 
exceptions, to write back to cc_op?

I'm thinking that should be able to remove TCGv_i32 cc_op in the translator and manually 
write back to the slot instead.  We already do a good job of caching the value within 
DisasContext -- I imagine that the final code wouldn't even change too much.

Which would allow us to drop

-DEF_HELPER_FLAGS_3(cgeb, TCG_CALL_NO_WG, i64, env, i64, i32)
-DEF_HELPER_FLAGS_3(cgdb, TCG_CALL_NO_WG, i64, env, i64, i32)
-DEF_HELPER_FLAGS_4(cgxb, TCG_CALL_NO_WG, i64, env, i64, i64, i32)
-DEF_HELPER_FLAGS_3(cfeb, TCG_CALL_NO_WG, i64, env, i64, i32)
-DEF_HELPER_FLAGS_3(cfdb, TCG_CALL_NO_WG, i64, env, i64, i32)
-DEF_HELPER_FLAGS_4(cfxb, TCG_CALL_NO_WG, i64, env, i64, i64, i32)
-DEF_HELPER_FLAGS_3(clgeb, TCG_CALL_NO_WG, i64, env, i64, i32)
-DEF_HELPER_FLAGS_3(clgdb, TCG_CALL_NO_WG, i64, env, i64, i32)
-DEF_HELPER_FLAGS_4(clgxb, TCG_CALL_NO_WG, i64, env, i64, i64, i32)
-DEF_HELPER_FLAGS_3(clfeb, TCG_CALL_NO_WG, i64, env, i64, i32)
-DEF_HELPER_FLAGS_3(clfdb, TCG_CALL_NO_WG, i64, env, i64, i32)
-DEF_HELPER_FLAGS_4(clfxb, TCG_CALL_NO_WG, i64, env, i64, i64, i32)
+DEF_HELPER_3(cgeb, i64, env, i64, i32)
+DEF_HELPER_3(cgdb, i64, env, i64, i32)
+DEF_HELPER_4(cgxb, i64, env, i64, i64, i32)
+DEF_HELPER_3(cfeb, i64, env, i64, i32)
+DEF_HELPER_3(cfdb, i64, env, i64, i32)
+DEF_HELPER_4(cfxb, i64, env, i64, i64, i32)
+DEF_HELPER_3(clgeb, i64, env, i64, i32)
+DEF_HELPER_3(clgdb, i64, env, i64, i32)
+DEF_HELPER_4(clgxb, i64, env, i64, i64, i32)
+DEF_HELPER_3(clfeb, i64, env, i64, i32)
+DEF_HELPER_3(clfdb, i64, env, i64, i32)
+DEF_HELPER_4(clfxb, i64, env, i64, i64, i32)

this bit.

I'll experiment this afternoon.


r~