Added support for 64bit

Author: john-sharratt

expected/wasm32-wasi/undefined-symbols.txt

@@ -1,4 +1,5 @@
 __addtf3
+__data_end
 __divtf3
 __eqtf2
 __extenddftf2
@@ -9,6 +10,7 @@ __fixunstfsi
 __floatsitf
 __floatunsitf
 __getf2
+__global_base
 __gttf2
 __heap_base
 __imported_wasix_32v1_args_get

expected/wasm64-wasi/undefined-symbols.txt

@@ -1,4 +1,5 @@
 __addtf3
+__data_end
 __divtf3
 __eqtf2
 __extenddftf2
@@ -9,6 +10,7 @@ __fixunstfsi
 __floatsitf
 __floatunsitf
 __getf2
+__global_base
 __gttf2
 __heap_base
 __imported_wasix_32v1_args_get

libc-top-half/musl/src/env/__init_tls.c

@@ -43,11 +43,19 @@ static inline void setup_default_stack_size()
 		stack_size = &__stack_high - &__stack_low;
 	else {
 		unsigned char *sp;
+#if defined(__wasm64__)
+		__asm__(
+			".globaltype __stack_pointer, i64\n"
+			"global.get __stack_pointer\n"
+			"local.set %0\n"
+			: "=r"(sp));
+#else
 		__asm__(
 			".globaltype __stack_pointer, i32\n"
 			"global.get __stack_pointer\n"
 			"local.set %0\n"
 			: "=r"(sp));
+#endif
 		stack_size = sp > &__global_base ? &__heap_base - &__data_end : (ptrdiff_t)&__global_base;
 	}