hw/cpu: Call object_class_is_abstract() once in cpu_class_by_name()

Let CPUClass::class_by_name() handlers to return abstract classes,
and filter them once in the public cpu_class_by_name() method.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230908112235.75914-3-philmd@linaro.org>

Author: philmd

hw/core/cpu-common.c

@@ -146,10 +146,18 @@ static bool cpu_common_has_work(CPUState *cs)
 
 ObjectClass *cpu_class_by_name(const char *typename, const char *cpu_model)
 {
-    CPUClass *cc = CPU_CLASS(object_class_by_name(typename));
-
-    assert(cpu_model && cc->class_by_name);
-    return cc->class_by_name(cpu_model);
+    ObjectClass *oc;
+    CPUClass *cc;
+
+    oc = object_class_by_name(typename);
+    cc = CPU_CLASS(oc);
+    assert(cc->class_by_name);
+    assert(cpu_model);
+    oc = cc->class_by_name(cpu_model);
+    if (oc == NULL || object_class_is_abstract(oc)) {
+        return NULL;
+    }
+    return oc;
 }
 
 static void cpu_common_parse_features(const char *typename, char *features,

include/hw/core/cpu.h

@@ -102,7 +102,7 @@ struct SysemuCPUOps;
 /**
  * CPUClass:
  * @class_by_name: Callback to map -cpu command line model name to an
- * instantiatable CPU type.
+ *                 instantiatable CPU type.
  * @parse_features: Callback to parse command line arguments.
  * @reset_dump_flags: #CPUDumpFlags to use for reset logging.
  * @has_work: Callback for checking if there is work to do.
@@ -772,9 +772,10 @@ void cpu_reset(CPUState *cpu);
  * @typename: The CPU base type.
  * @cpu_model: The model string without any parameters.
  *
- * Looks up a CPU #ObjectClass matching name @cpu_model.
+ * Looks up a concrete CPU #ObjectClass matching name @cpu_model.
  *
- * Returns: A #CPUClass or %NULL if not matching class is found.
+ * Returns: A concrete #CPUClass or %NULL if no matching class is found
+ *          or if the matching class is abstract.
  */
 ObjectClass *cpu_class_by_name(const char *typename, const char *cpu_model);
 

target/alpha/cpu.c

@@ -126,8 +126,7 @@ static ObjectClass *alpha_cpu_class_by_name(const char *cpu_model)
     int i;
 
     oc = object_class_by_name(cpu_model);
-    if (oc != NULL && object_class_dynamic_cast(oc, TYPE_ALPHA_CPU) != NULL &&
-        !object_class_is_abstract(oc)) {
+    if (oc != NULL && object_class_dynamic_cast(oc, TYPE_ALPHA_CPU) != NULL) {
         return oc;
     }
 

target/arm/cpu.c

@@ -2401,8 +2401,7 @@ static ObjectClass *arm_cpu_class_by_name(const char *cpu_model)
     oc = object_class_by_name(typename);
     g_strfreev(cpuname);
     g_free(typename);
-    if (!oc || !object_class_dynamic_cast(oc, TYPE_ARM_CPU) ||
-        object_class_is_abstract(oc)) {
+    if (!oc || !object_class_dynamic_cast(oc, TYPE_ARM_CPU)) {
         return NULL;
     }
     return oc;

target/avr/cpu.c

@@ -157,8 +157,7 @@ static ObjectClass *avr_cpu_class_by_name(const char *cpu_model)
     ObjectClass *oc;
 
     oc = object_class_by_name(cpu_model);
-    if (object_class_dynamic_cast(oc, TYPE_AVR_CPU) == NULL ||
-        object_class_is_abstract(oc)) {
+    if (object_class_dynamic_cast(oc, TYPE_AVR_CPU) == NULL) {
         oc = NULL;
     }
     return oc;

target/cris/cpu.c

@@ -95,8 +95,7 @@ static ObjectClass *cris_cpu_class_by_name(const char *cpu_model)
     typename = g_strdup_printf(CRIS_CPU_TYPE_NAME("%s"), cpu_model);
     oc = object_class_by_name(typename);
     g_free(typename);
-    if (oc != NULL && (!object_class_dynamic_cast(oc, TYPE_CRIS_CPU) ||
-                       object_class_is_abstract(oc))) {
+    if (oc != NULL && !object_class_dynamic_cast(oc, TYPE_CRIS_CPU)) {
         oc = NULL;
     }
     return oc;

target/hexagon/cpu.c

@@ -63,8 +63,7 @@ static ObjectClass *hexagon_cpu_class_by_name(const char *cpu_model)
     oc = object_class_by_name(typename);
     g_strfreev(cpuname);
     g_free(typename);
-    if (!oc || !object_class_dynamic_cast(oc, TYPE_HEXAGON_CPU) ||
-        object_class_is_abstract(oc)) {
+    if (!oc || !object_class_dynamic_cast(oc, TYPE_HEXAGON_CPU)) {
         return NULL;
     }
     return oc;

target/loongarch/cpu.c

@@ -721,8 +721,7 @@ static ObjectClass *loongarch_cpu_class_by_name(const char *cpu_model)
         }
     }
 
-    if (object_class_dynamic_cast(oc, TYPE_LOONGARCH_CPU)
-        && !object_class_is_abstract(oc)) {
+    if (object_class_dynamic_cast(oc, TYPE_LOONGARCH_CPU)) {
         return oc;
     }
     return NULL;

target/m68k/cpu.c

@@ -111,8 +111,7 @@ static ObjectClass *m68k_cpu_class_by_name(const char *cpu_model)
     typename = g_strdup_printf(M68K_CPU_TYPE_NAME("%s"), cpu_model);
     oc = object_class_by_name(typename);
     g_free(typename);
-    if (oc != NULL && (object_class_dynamic_cast(oc, TYPE_M68K_CPU) == NULL ||
-                       object_class_is_abstract(oc))) {
+    if (oc != NULL && object_class_dynamic_cast(oc, TYPE_M68K_CPU) == NULL) {
         return NULL;
     }
     return oc;

target/openrisc/cpu.c

@@ -164,8 +164,7 @@ static ObjectClass *openrisc_cpu_class_by_name(const char *cpu_model)
     typename = g_strdup_printf(OPENRISC_CPU_TYPE_NAME("%s"), cpu_model);
     oc = object_class_by_name(typename);
     g_free(typename);
-    if (oc != NULL && (!object_class_dynamic_cast(oc, TYPE_OPENRISC_CPU) ||
-                       object_class_is_abstract(oc))) {
+    if (oc != NULL && !object_class_dynamic_cast(oc, TYPE_OPENRISC_CPU)) {
         return NULL;
     }
     return oc;