[Qemu-devel] [PATCH 2/4] target/s390x: End the TB after EXECUTE

[Richard Henderson <rth@twiddle.net>]

This split will be required for implementing EXECUTE properly.
Do this now as a separate step to aid comparison of before and
after TB listings.

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 target/s390x/mem_helper.c | 54 ++++++++++++++++++++++++++++-------------------
 target/s390x/translate.c  |  6 +++++-
 2 files changed, 37 insertions(+), 23 deletions(-)

diff --git a/target/s390x/mem_helper.c b/target/s390x/mem_helper.c
index 4b96c27..d57d5b1 100644
--- a/target/s390x/mem_helper.c
+++ b/target/s390x/mem_helper.c
@@ -1234,6 +1234,7 @@ void HELPER(ex)(CPUS390XState *env, uint32_t ilen, uint64_t r1, uint64_t addr)
     S390CPU *cpu = s390_env_get_cpu(env);
     uint64_t insn = cpu_lduw_code(env, addr);
     uint8_t opc = insn >> 8;
+    uint32_t cc;
 
     /* Or in the contents of R1[56:63].  */
     insn |= r1 & 0xff;
@@ -1263,42 +1264,46 @@ void HELPER(ex)(CPUS390XState *env, uint32_t ilen, uint64_t r1, uint64_t addr)
         b2 = extract64(insn, 28, 4);
         d1 = extract64(insn, 32, 12);
         d2 = extract64(insn, 16, 12);
+
+        cc = env->cc_op;
         switch (opc & 0xf) {
         case 0x2:
             do_helper_mvc(env, l, get_address(env, 0, b1, d1),
                           get_address(env, 0, b2, d2), 0);
-            return;
+            break;
         case 0x4:
-            env->cc_op = do_helper_nc(env, l, get_address(env, 0, b1, d1),
-                                      get_address(env, 0, b2, d2), 0);
-            return;
+            cc = do_helper_nc(env, l, get_address(env, 0, b1, d1),
+                              get_address(env, 0, b2, d2), 0);
+            break;
         case 0x5:
-            env->cc_op = do_helper_clc(env, l, get_address(env, 0, b1, d1),
-                                       get_address(env, 0, b2, d2), 0);
-            return;
+            cc = do_helper_clc(env, l, get_address(env, 0, b1, d1),
+                               get_address(env, 0, b2, d2), 0);
+            break;
         case 0x6:
-            env->cc_op = do_helper_oc(env, l, get_address(env, 0, b1, d1),
-                                      get_address(env, 0, b2, d2), 0);
-            return;
+            cc = do_helper_oc(env, l, get_address(env, 0, b1, d1),
+                              get_address(env, 0, b2, d2), 0);
+            break;
         case 0x7:
-            env->cc_op = do_helper_xc(env, l, get_address(env, 0, b1, d1),
-                                      get_address(env, 0, b2, d2), 0);
-            return;
+            cc = do_helper_xc(env, l, get_address(env, 0, b1, d1),
+                              get_address(env, 0, b2, d2), 0);
+            break;
         case 0xc:
             do_helper_tr(env, l, get_address(env, 0, b1, d1),
                          get_address(env, 0, b2, d2), 0);
-            return;
+            break;
         case 0xd:
-            env->cc_op = do_helper_trt(env, l, get_address(env, 0, b1, d1),
-                                       get_address(env, 0, b2, d2), 0);
-            return;
+            cc = do_helper_trt(env, l, get_address(env, 0, b1, d1),
+                               get_address(env, 0, b2, d2), 0);
+            break;
+        default:
+            goto abort;
         }
     } else if (opc == 0x0a) {
         /* supervisor call */
         env->int_svc_code = extract64(insn, 48, 8);
         env->int_svc_ilen = ilen;
         helper_exception(env, EXCP_SVC);
-        return;
+        g_assert_not_reached();
     } else if (opc == 0xbf) {
         uint32_t r1, r3, b2, d2;
 
@@ -1306,10 +1311,15 @@ void HELPER(ex)(CPUS390XState *env, uint32_t ilen, uint64_t r1, uint64_t addr)
         r3 = extract64(insn, 48, 4);
         b2 = extract64(insn, 44, 4);
         d2 = extract64(insn, 32, 12);
-        env->cc_op = helper_icm(env, r1, get_address(env, 0, b2, d2), r3);
-        return;
+        cc = helper_icm(env, r1, get_address(env, 0, b2, d2), r3);
+    } else {
+ abort:
+        cpu_abort(CPU(cpu),
+                  "EXECUTE on instruction prefix 0x%x not implemented\n",
+                  opc);
+        g_assert_not_reached();
     }
 
-    cpu_abort(CPU(cpu), "EXECUTE on instruction prefix 0x%x not implemented\n",
-              opc);
+    env->cc_op = cc;
+    env->psw.addr += ilen;
 }
diff --git a/target/s390x/translate.c b/target/s390x/translate.c
index 5b8333f..70212c8 100644
--- a/target/s390x/translate.c
+++ b/target/s390x/translate.c
@@ -1163,6 +1163,8 @@ typedef enum {
        the PC (for whatever reason), so there's no need to do it again on
        exiting the TB.  */
     EXIT_PC_UPDATED,
+    /* We have updated the PC and CC values.  */
+    EXIT_PC_CC_UPDATED,
     /* We are exiting the TB, but have neither emitted a goto_tb, nor
        updated the PC for the next instruction to be executed.  */
     EXIT_PC_STALE,
@@ -2216,7 +2218,7 @@ static ExitStatus op_ex(DisasContext *s, DisasOps *o)
         tcg_temp_free_i64(v1);
     }
 
-    return NO_EXIT;
+    return EXIT_PC_CC_UPDATED;
 }
 
 static ExitStatus op_fieb(DisasContext *s, DisasOps *o)
@@ -5489,6 +5491,8 @@ void gen_intermediate_code(CPUS390XState *env, struct TranslationBlock *tb)
         /* Next TB starts off with CC_OP_DYNAMIC, so make sure the
            cc op type is in env */
         update_cc_op(&dc);
+        /* FALLTHRU */
+    case EXIT_PC_CC_UPDATED:
         /* Exit the TB, either by raising a debug exception or by return.  */
         if (do_debug) {
             gen_exception(EXCP_DEBUG);
-- 
2.9.4