target/i386: Add support for AMX-COMPLEX in CPUID enumeration

Latest Intel platform GraniteRapids-D introduces AMX-COMPLEX, which adds
two instructions to perform matrix multiplication of two tiles containing
complex elements and accumulate the results into a packed single precision
tile.

AMX-COMPLEX is enumerated via CPUID.(EAX=7,ECX=1):EDX[bit 8]. Add the CPUID
definition for AMX-COMPLEX, AMX-COMPLEX will be enabled automatically when
using '-cpu host' and KVM advertises AMX-COMPLEX to userspace.

Signed-off-by: Tao Su <tao1.su@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-ID: <20230830074324.84059-1-tao1.su@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

target/i386/cpu.c

@@ -980,7 +980,7 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
         .feat_names = {
             NULL, NULL, NULL, NULL,
             "avx-vnni-int8", "avx-ne-convert", NULL, NULL,
-            NULL, NULL, NULL, NULL,
+            "amx-complex", NULL, NULL, NULL,
             NULL, NULL, "prefetchiti", NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,

target/i386/cpu.h

@@ -930,6 +930,8 @@ uint64_t x86_cpu_get_supported_feature_word(FeatureWord w,
 #define CPUID_7_1_EDX_AVX_VNNI_INT8     (1U << 4)
 /* AVX NE CONVERT Instructions */
 #define CPUID_7_1_EDX_AVX_NE_CONVERT    (1U << 5)
+/* AMX COMPLEX Instructions */
+#define CPUID_7_1_EDX_AMX_COMPLEX       (1U << 8)
 /* PREFETCHIT0/1 Instructions */
 #define CPUID_7_1_EDX_PREFETCHITI       (1U << 14)