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>

1 files changed, 12 insertions, 4 deletions

diff --git a/hw/core/cpu-common.c b/hw/core/cpu-common.c
index baa6d28b64..d4112b8919 100644
--- a/hw/core/cpu-common.c
+++ b/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,