[PATCH v3 30/33] target/sh4: Use a static table in sh4_exception_name()

["Philippe Mathieu-Daudé" <philmd@oss.qualcomm.com>]

Replace the switch statement with a static lookup table.

With '-d int', unlisted exception codes are now logged as
"unknown" instead of "???".

Suggested-by: Pierrick Bouvier <pierrick.bouvier@oss.qualcomm.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@oss.qualcomm.com>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@oss.qualcomm.com>
---
 target/sh4/helper.c | 66 ++++++++++++++-------------------------------
 1 file changed, 20 insertions(+), 46 deletions(-)

diff --git a/target/sh4/helper.c b/target/sh4/helper.c
index 5856bab6983..96465dd94fb 100644
--- a/target/sh4/helper.c
+++ b/target/sh4/helper.c
@@ -18,6 +18,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/cutils.h"
 
 #include "cpu.h"
 #include "exec/cputlb.h"
@@ -49,54 +50,27 @@
 
 const char *sh4_exception_name(int excp)
 {
-    const char *name;
+    /* Exception codes (EXPEVT) are multiples of 0x20 */
+    static const char * const excp_names[] = {
+        [SH4_EXCP_ADDR_ERROR >> 5]               = "addr_error",
+        [SH4_EXCP_TLB_MISS >> 5]                 = "tlb_miss",
+        [SH4_EXCP_TLB_VIOLATION >> 5]            = "tlb_violation",
+        [SH4_EXCP_ILLEGAL_INSTRUCTION >> 5]      = "illegal_instruction",
+        [SH4_EXCP_SLOT_ILLEGAL_INSTRUCTION >> 5] = "slot_illegal_instruction",
+        [SH4_EXCP_FPU_DISABLE >> 5]              = "fpu_disable",
+        [SH4_EXCP_SLOT_FPU_DISABLE >> 5]         = "slot_fpu",
+        [SH4_EXCP_DATA_WRITE >> 5]               = "data_write",
+        [SH4_EXCP_DTLB_MISS_WRITE >> 5]          = "dtlb_miss_write",
+        [SH4_EXCP_DTLB_VIOLATION_WRITE >> 5]     = "dtlb_violation_write",
+        [SH4_EXCP_FPU >> 5]                      = "fpu_exception",
+        [SH4_EXCP_INITIAL_PAGE_WRITE >> 5]       = "initial_page_write",
+        [SH4_EXCP_TRAPA >> 5]                    = "trapa",
+    };
 
-    switch (excp) {
-    case SH4_EXCP_ADDR_ERROR:
-        name = "addr_error";
-        break;
-    case SH4_EXCP_TLB_MISS:
-        name = "tlb_miss";
-        break;
-    case SH4_EXCP_TLB_VIOLATION:
-        name = "tlb_violation";
-        break;
-    case SH4_EXCP_ILLEGAL_INSTRUCTION:
-        name = "illegal_instruction";
-        break;
-    case SH4_EXCP_SLOT_ILLEGAL_INSTRUCTION:
-        name = "slot_illegal_instruction";
-        break;
-    case SH4_EXCP_FPU_DISABLE:
-        name = "fpu_disable";
-        break;
-    case SH4_EXCP_SLOT_FPU_DISABLE:
-        name = "slot_fpu";
-        break;
-    case SH4_EXCP_DATA_WRITE:
-        name = "data_write";
-        break;
-    case SH4_EXCP_DTLB_MISS_WRITE:
-        name = "dtlb_miss_write";
-        break;
-    case SH4_EXCP_DTLB_VIOLATION_WRITE:
-        name = "dtlb_violation_write";
-        break;
-    case SH4_EXCP_FPU:
-        name = "fpu_exception";
-        break;
-    case SH4_EXCP_INITIAL_PAGE_WRITE:
-        name = "initial_page_write";
-        break;
-    case SH4_EXCP_TRAPA:
-        name = "trapa";
-        break;
-    default:
-        name = "???";
-        break;
+    if (excp & 0x1f) {
+        return "unknown";
     }
-
-    return name;
+    return STR_ARRAY_ELEM_OR_NULL(excp_names, excp >> 5) ?: "unknown";
 }
 
 #if defined(CONFIG_USER_ONLY)
-- 
2.55.0