Merge pull request #3169 from juju812/bugfix/i8mm-check

CPURuntime: Bugfix: check i8mm support by AT_HWCAP2

source/backend/cpu/CPURuntime.cpp

@@ -24,13 +24,15 @@
 #include <sys/types.h>
 #include <dirent.h>
 
+// HWCAP flags
 #define CPUINFO_ARM_LINUX_FEATURE_FPHP UINT32_C(0x00000200)
 #define CPUINFO_ARM_LINUX_FEATURE_ASIMDHP UINT32_C(0x00000400)
 #define CPUINFO_ARM_LINUX_FEATURE_ASIMDDP UINT32_C(0x00100000)
-// ref: https://cs.android.com/android/platform/superproject/+/master:bionic/libc/kernel/uapi/asm-arm64/asm/hwcap.h;drc=04da58f5b3bc40dbbafb4f8422aa2991479d9e1e;l=70
-#define CPUINFO_ARM_LINUX_FEATURE_I8MM UINT32_C(0x00002000)
 #define CPUINFO_ARM_LINUX_FEATURE_SVE UINT32_C(0x00400000)
+// HWCAP2 flags
 #define CPUINFO_ARM_LINUX_FEATURE_SVE2 UINT32_C(0x00000002)
+// ref: https://cs.android.com/android/platform/superproject/+/master:bionic/libc/kernel/uapi/asm-arm64/asm/hwcap.h;drc=04da58f5b3bc40dbbafb4f8422aa2991479d9e1e;l=70
+#define CPUINFO_ARM_LINUX_FEATURE_I8MM UINT32_C(0x00002000)
 #endif
 
 #include <algorithm>
@@ -1288,6 +1290,7 @@ static void _getInfoApple(MNNCPUInfo* cpuinfo_isa) {
 static void _getInfoAux(MNNCPUInfo* cpuinfo_isa) {
     // Use AUX to get info for linux-aarch64
     uint32_t isa_features = 0;
+    // HWCAP features
     isa_features = (uint32_t)getauxval(AT_HWCAP);
     if (isa_features & CPUINFO_ARM_LINUX_FEATURE_ASIMDDP) {
         cpuinfo_isa->dot = true;
@@ -1296,10 +1299,11 @@ static void _getInfoAux(MNNCPUInfo* cpuinfo_isa) {
     if ((isa_features & fp16arith_mask) == fp16arith_mask) {
         cpuinfo_isa->fp16arith = true;
     }
+    // HWCAP2 features
+    isa_features = (uint32_t)getauxval(AT_HWCAP2);
     if (isa_features & CPUINFO_ARM_LINUX_FEATURE_I8MM) {
         cpuinfo_isa->i8mm = true;
     }
-    isa_features = (uint32_t)getauxval(AT_HWCAP2);
     if (isa_features & CPUINFO_ARM_LINUX_FEATURE_SVE2) {
         cpuinfo_isa->sve2 = true;
     }