wasm2c: fix big endian guard page support

Author: shravanrn

src/prebuilt/wasm2c_simd_source_declarations.cc

@@ -6,6 +6,10 @@ R"w2c_template(#elif defined(__GNUC__) && defined(__aarch64__)
 )w2c_template"
 R"w2c_template(#define SIMD_FORCE_READ(var) __asm__("" ::"w"(var));
 )w2c_template"
+R"w2c_template(#elif defined(__s390x__)
+)w2c_template"
+R"w2c_template(#define SIMD_FORCE_READ(var) __asm__("" ::"d"(var));
+)w2c_template"
 R"w2c_template(#else
 )w2c_template"
 R"w2c_template(#define SIMD_FORCE_READ(var)

src/template/wasm2c_simd.declarations.c

@@ -2,6 +2,8 @@
 #define SIMD_FORCE_READ(var) __asm__("" ::"x"(var));
 #elif defined(__GNUC__) && defined(__aarch64__)
 #define SIMD_FORCE_READ(var) __asm__("" ::"w"(var));
+#elif defined(__s390x__)
+#define SIMD_FORCE_READ(var) __asm__("" ::"d"(var));
 #else
 #define SIMD_FORCE_READ(var)
 #endif

wasm2c/wasm-rt.h

@@ -142,12 +142,11 @@ extern "C" {
  *
  * This defaults to GUARD_PAGES as this is the fastest option, iff the
  * requirements of GUARD_PAGES --- 64-bit platforms, MMAP allocation strategy,
- * no 64-bit memories, no big-endian --- are met. This falls back to BOUNDS
- * otherwise.
+ * no 64-bit memories --- are met. This falls back to BOUNDS otherwise.
  */
 
 /** Check if Guard checks are supported */
-#if UINTPTR_MAX > 0xffffffff && WASM_RT_USE_MMAP && !WABT_BIG_ENDIAN
+#if UINTPTR_MAX > 0xffffffff && WASM_RT_USE_MMAP
 #define WASM_RT_GUARD_PAGES_SUPPORTED 1
 #else
 #define WASM_RT_GUARD_PAGES_SUPPORTED 0