Fix arm64 issues on mac (#3688)

Make wamrc normalize "arm64" to "aarch64v8". Previously the only way to
make the "arm64" target was to not specify a target on 64 bit arm-based
mac builds. Now arm64 and aarch64v8 are treated as the same.

Make aot_loader accept "aarch64v8" on arm-based apple (as well as
accepting legacy "arm64" based aot targets).

This also removes __APPLE__ and __MACH__ from the block that defaults
size_level to 1 since it doesn't seem to be supported for aarch64:
`LLVM ERROR: Only small, tiny and large code models are allowed on AArch64`

core/iwasm/aot/aot_loader.c

@@ -579,6 +579,10 @@ load_target_info_section(const uint8 *buf, const uint8 *buf_end,
         return false;
     }
 
+    /* for backwards compatibility with previous wamrc aot files */
+    if (!strcmp(target_info.arch, "arm64"))
+        bh_strcpy_s(target_info.arch, sizeof(target_info.arch), "aarch64v8");
+
     /* Check machine info */
     if (!check_machine_info(&target_info, error_buf, error_buf_size)) {
         return false;

core/iwasm/aot/arch/aot_reloc_aarch64.c

@@ -53,12 +53,6 @@ get_target_symbol_map(uint32 *sym_num)
     return target_sym_map;
 }
 
-#if (defined(__APPLE__) || defined(__MACH__)) && defined(__arm64__)
-#define BUILD_TARGET_AARCH64_DEFAULT "arm64"
-#else
-#define BUILD_TARGET_AARCH64_DEFAULT "aarch64v8"
-#endif
-
 void
 get_current_target(char *target_buf, uint32 target_buf_size)
 {
@@ -68,8 +62,8 @@ get_current_target(char *target_buf, uint32 target_buf_size)
 
     /* Set to "aarch64v8" by default if sub version isn't specified */
     if (strcmp(s, "AARCH64") == 0) {
-        s = BUILD_TARGET_AARCH64_DEFAULT;
-        s_size = sizeof(BUILD_TARGET_AARCH64_DEFAULT);
+        s = "aarch64v8";
+        s_size = 9; /* strlen("aarch64v8"); */
     }
     if (target_buf_size < s_size) {
         s_size = target_buf_size;
@@ -83,7 +77,6 @@ get_current_target(char *target_buf, uint32 target_buf_size)
     /* Ensure the string is null byte ('\0') terminated */
     *d = '\0';
 }
-#undef BUILD_TARGET_AARCH64_DEFAULT
 
 static uint32
 get_plt_item_size()

core/iwasm/compilation/aot_llvm.c

@@ -2790,6 +2790,15 @@ aot_create_comp_context(const AOTCompData *comp_data, aot_comp_option_t option)
                 bh_assert(vendor_sys);
                 bh_memcpy_s(default_arch, sizeof(default_arch), default_triple,
                             (uint32)(vendor_sys - default_triple));
+                /**
+                 * On Mac M[1-9]+ LLVM will report arm64 as the
+                 * architecture, for the purposes of wamr this is the
+                 * same as aarch64v8 so we'll normalize it here.
+                 */
+                if (!strcmp(default_arch, "arm64")) {
+                    bh_strcpy_s(default_arch, sizeof(default_arch),
+                                "aarch64v8");
+                }
                 arch1 = default_arch;
 
                 LLVMDisposeMessage(default_triple);

wamr-compiler/main.c

@@ -601,8 +601,8 @@ main(int argc, char *argv[])
             LOG_VERBOSE("Set size level to 1 for Windows AOT file");
             option.size_level = 1;
         }
-#if defined(_WIN32) || defined(_WIN32_) || defined(__APPLE__) \
-    || defined(__MACH__)
+#if defined(_WIN32) || defined(_WIN32_) \
+    || ((defined(__APPLE__) || defined(__MACH__)) && !defined(__arm64__))
         if (!option.target_arch && !option.target_abi) {
             LOG_VERBOSE("Set size level to 1 for Windows or MacOS AOT file");
             option.size_level = 1;