target/m68k: Switch over exception type in m68k_interrupt_all

Replace an if ladder with a switch for clarity.

Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220602013401.303699-3-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

1 files changed, 30 insertions, 19 deletions

diff --git a/target/m68k/op_helper.c b/target/m68k/op_helper.c
index d30f988..2b94a6e 100644
--- a/target/m68k/op_helper.c
+++ b/target/m68k/op_helper.c
@@ -333,7 +333,8 @@ static void m68k_interrupt_all(CPUM68KState *env, int is_hw)
         sp &= ~1;
     }
 
-    if (cs->exception_index == EXCP_ACCESS) {
+    switch (cs->exception_index) {
+    case EXCP_ACCESS:
         if (env->mmu.fault) {
             cpu_abort(cs, "DOUBLE MMU FAULT\n");
         }
@@ -391,29 +392,39 @@ static void m68k_interrupt_all(CPUM68KState *env, int is_hw)
                      "ssw:  %08x ea:   %08x sfc:  %d    dfc: %d\n",
                      env->mmu.ssw, env->mmu.ar, env->sfc, env->dfc);
         }
-    } else if (cs->exception_index == EXCP_ADDRESS) {
+        break;
+
+    case EXCP_ADDRESS:
         do_stack_frame(env, &sp, 2, oldsr, 0, retaddr);
-    } else if (cs->exception_index == EXCP_ILLEGAL ||
-               cs->exception_index == EXCP_DIV0 ||
-               cs->exception_index == EXCP_CHK ||
-               cs->exception_index == EXCP_TRAPCC ||
-               cs->exception_index == EXCP_TRACE) {
+        break;
+
+    case EXCP_ILLEGAL:
+    case EXCP_DIV0:
+    case EXCP_CHK:
+    case EXCP_TRAPCC:
+    case EXCP_TRACE:
         /* FIXME: addr is not only env->pc */
         do_stack_frame(env, &sp, 2, oldsr, env->pc, retaddr);
-    } else if (is_hw && oldsr & SR_M &&
-               cs->exception_index >= EXCP_SPURIOUS &&
-               cs->exception_index <= EXCP_INT_LEVEL_7) {
-        do_stack_frame(env, &sp, 0, oldsr, 0, retaddr);
-        oldsr = sr;
-        env->aregs[7] = sp;
-        cpu_m68k_set_sr(env, sr &= ~SR_M);
-        sp = env->aregs[7];
-        if (!m68k_feature(env, M68K_FEATURE_UNALIGNED_DATA)) {
-            sp &= ~1;
+        break;
+
+    case EXCP_SPURIOUS ... EXCP_INT_LEVEL_7:
+        if (is_hw && oldsr & SR_M) {
+            do_stack_frame(env, &sp, 0, oldsr, 0, retaddr);
+            oldsr = sr;
+            env->aregs[7] = sp;
+            cpu_m68k_set_sr(env, sr &= ~SR_M);
+            sp = env->aregs[7];
+            if (!m68k_feature(env, M68K_FEATURE_UNALIGNED_DATA)) {
+                sp &= ~1;
+            }
+            do_stack_frame(env, &sp, 1, oldsr, 0, retaddr);
+            break;
         }
-        do_stack_frame(env, &sp, 1, oldsr, 0, retaddr);
-    } else {
+        /* fall through */
+
+    default:
         do_stack_frame(env, &sp, 0, oldsr, 0, retaddr);
+        break;
     }
 
     env->aregs[7] = sp;