[Stable-8.2.3 52/87] target/loongarch: Fix qemu-system-loongarch64 assert failed with the option '-d int'

[Michael Tokarev]

From: Song Gao <gaos...@loongson.cn>

qemu-system-loongarch64 assert failed with the option '-d int',
the helper_idle() raise an exception EXCP_HLT, but the exception name is 
undefined.

Signed-off-by: Song Gao <gaos...@loongson.cn>
Reviewed-by: Philippe Mathieu-Daudé <phi...@linaro.org>
Message-Id: <20240321123606.1704900-1-gaos...@loongson.cn>
(cherry picked from commit 1590154ee4376819a8c6ee61e849ebf4a4e7cd02)
Signed-off-by: Michael Tokarev <m...@tls.msk.ru>

diff --git a/target/loongarch/cpu.c b/target/loongarch/cpu.c
index fc075952e6..570201e616 100644
--- a/target/loongarch/cpu.c
+++ b/target/loongarch/cpu.c
@@ -35,33 +35,45 @@ const char * const fregnames[32] = {
     "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31",
 };
 
-static const char * const excp_names[] = {
-    [EXCCODE_INT] = "Interrupt",
-    [EXCCODE_PIL] = "Page invalid exception for load",
-    [EXCCODE_PIS] = "Page invalid exception for store",
-    [EXCCODE_PIF] = "Page invalid exception for fetch",
-    [EXCCODE_PME] = "Page modified exception",
-    [EXCCODE_PNR] = "Page Not Readable exception",
-    [EXCCODE_PNX] = "Page Not Executable exception",
-    [EXCCODE_PPI] = "Page Privilege error",
-    [EXCCODE_ADEF] = "Address error for instruction fetch",
-    [EXCCODE_ADEM] = "Address error for Memory access",
-    [EXCCODE_SYS] = "Syscall",
-    [EXCCODE_BRK] = "Break",
-    [EXCCODE_INE] = "Instruction Non-Existent",
-    [EXCCODE_IPE] = "Instruction privilege error",
-    [EXCCODE_FPD] = "Floating Point Disabled",
-    [EXCCODE_FPE] = "Floating Point Exception",
-    [EXCCODE_DBP] = "Debug breakpoint",
-    [EXCCODE_BCE] = "Bound Check Exception",
-    [EXCCODE_SXD] = "128 bit vector instructions Disable exception",
-    [EXCCODE_ASXD] = "256 bit vector instructions Disable exception",
+struct TypeExcp {
+    int32_t exccode;
+    const char * const name;
+};
+
+static const struct TypeExcp excp_names[] = {
+    {EXCCODE_INT, "Interrupt"},
+    {EXCCODE_PIL, "Page invalid exception for load"},
+    {EXCCODE_PIS, "Page invalid exception for store"},
+    {EXCCODE_PIF, "Page invalid exception for fetch"},
+    {EXCCODE_PME, "Page modified exception"},
+    {EXCCODE_PNR, "Page Not Readable exception"},
+    {EXCCODE_PNX, "Page Not Executable exception"},
+    {EXCCODE_PPI, "Page Privilege error"},
+    {EXCCODE_ADEF, "Address error for instruction fetch"},
+    {EXCCODE_ADEM, "Address error for Memory access"},
+    {EXCCODE_SYS, "Syscall"},
+    {EXCCODE_BRK, "Break"},
+    {EXCCODE_INE, "Instruction Non-Existent"},
+    {EXCCODE_IPE, "Instruction privilege error"},
+    {EXCCODE_FPD, "Floating Point Disabled"},
+    {EXCCODE_FPE, "Floating Point Exception"},
+    {EXCCODE_DBP, "Debug breakpoint"},
+    {EXCCODE_BCE, "Bound Check Exception"},
+    {EXCCODE_SXD, "128 bit vector instructions Disable exception"},
+    {EXCCODE_ASXD, "256 bit vector instructions Disable exception"},
+    {EXCP_HLT, "EXCP_HLT"},
 };
 
 const char *loongarch_exception_name(int32_t exception)
 {
-    assert(excp_names[exception]);
-    return excp_names[exception];
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(excp_names); i++) {
+        if (excp_names[i].exccode == exception) {
+            return excp_names[i].name;
+        }
+    }
+    return "Unknown";
 }
 
 void G_NORETURN do_raise_exception(CPULoongArchState *env,
@@ -70,7 +82,7 @@ void G_NORETURN do_raise_exception(CPULoongArchState *env,
 {
     CPUState *cs = env_cpu(env);
 
-    qemu_log_mask(CPU_LOG_INT, "%s: %d (%s)\n",
+    qemu_log_mask(CPU_LOG_INT, "%s: expection: %d (%s)\n",
                   __func__,
                   exception,
                   loongarch_exception_name(exception));
@@ -145,22 +157,16 @@ static void loongarch_cpu_do_interrupt(CPUState *cs)
     CPULoongArchState *env = &cpu->env;
     bool update_badinstr = 1;
     int cause = -1;
-    const char *name;
     bool tlbfill = FIELD_EX64(env->CSR_TLBRERA, CSR_TLBRERA, ISTLBR);
     uint32_t vec_size = FIELD_EX64(env->CSR_ECFG, CSR_ECFG, VS);
 
     if (cs->exception_index != EXCCODE_INT) {
-        if (cs->exception_index < 0 ||
-            cs->exception_index >= ARRAY_SIZE(excp_names)) {
-            name = "unknown";
-        } else {
-            name = excp_names[cs->exception_index];
-        }
-
         qemu_log_mask(CPU_LOG_INT,
                      "%s enter: pc " TARGET_FMT_lx " ERA " TARGET_FMT_lx
-                     " TLBRERA " TARGET_FMT_lx " %s exception\n", __func__,
-                     env->pc, env->CSR_ERA, env->CSR_TLBRERA, name);
+                     " TLBRERA " TARGET_FMT_lx " exception: %d (%s)\n",
+                     __func__, env->pc, env->CSR_ERA, env->CSR_TLBRERA,
+                     cs->exception_index,
+                     loongarch_exception_name(cs->exception_index));
     }
 
     switch (cs->exception_index) {
-- 
2.39.2