[Wasm64] Allow testing of wasm64 + standalone (emscripten-core#18771)

Author: sbc100

system/lib/standalone/standalone.c

@@ -142,7 +142,10 @@ int emscripten_resize_heap(size_t size) {
   assert(old_size < size);
   ssize_t diff = (size - old_size + WASM_PAGE_SIZE - 1) / WASM_PAGE_SIZE;
   size_t result = __builtin_wasm_memory_grow(0, diff);
-  if (result != (size_t)-1) {
+  // Its seems v8 has a bug in memory.grow that causes it to return 
+  // (uint32_t)-1 even with memory64:
+  // https://bugs.chromium.org/p/v8/issues/detail?id=13948
+  if (result != (uint32_t)-1 && result != (size_t)-1) {
     // Success, update JS (see https://github.com/WebAssembly/WASI/issues/82)
     emscripten_notify_memory_growth(0);
     return 1;

test/common.py

@@ -515,6 +515,7 @@ def require_engine(self, engine):
       self.skipTest(f'Skipping test that requires `{engine}` when `{self.required_engine}` was previously required')
     self.required_engine = engine
     self.js_engines = [engine]
+    self.wasm_engines = []
 
   def require_wasm64(self):
     if config.NODE_JS and config.NODE_JS in self.js_engines:

test/test_core.py

@@ -156,12 +156,20 @@ def metafunc(self, rawfs):
   return metafunc
 
 
-def can_do_standalone(self):
+def can_do_wasm2c(self):
+  # the npm version of wasm2c does not support MEMORY64
+  return not self.get_setting('MEMORY64')
+
+
+def can_do_standalone(self, impure=False):
+  # Pure standalone engines don't support MEMORY64 yet.  Even with MEMORY64=2 (lowered)
+  # the WASI APIs that take pointer values don't have 64-bit variants yet.
+  if self.get_setting('MEMORY64') and not impure:
+    return False
   return self.is_wasm() and \
       self.get_setting('STACK_OVERFLOW_CHECK', 0) < 2 and \
       not self.get_setting('MINIMAL_RUNTIME') and \
       not self.get_setting('SAFE_HEAP') and \
-      not self.get_setting('MEMORY64') and \
       not any(a.startswith('-fsanitize=') for a in self.emcc_args)
 
 
@@ -202,7 +210,7 @@ def metafunc(self, standalone):
       if not standalone:
         func(self)
       else:
-        if not can_do_standalone(self):
+        if not can_do_standalone(self, impure):
           self.skipTest('Test configuration is not compatible with STANDALONE_WASM')
         self.set_setting('STANDALONE_WASM')
         # we will not legalize the JS ffi interface, so we must use BigInt
@@ -213,10 +221,9 @@ def metafunc(self, standalone):
         # if we are impure, disallow all wasm engines
         if impure:
           self.wasm_engines = []
-        self.js_engines = [config.NODE_JS]
         self.node_args += shared.node_bigint_flags()
         func(self)
-        if wasm2c:
+        if wasm2c and can_do_wasm2c(self):
           print('wasm2c')
           self.set_setting('WASM2C')
           self.wasm_engines = []
@@ -7160,6 +7167,8 @@ def test_wasm2c_sandboxing(self, mode):
       self.node_args += shared.node_bigint_flags()
     if not can_do_standalone(self):
       return self.skipTest('standalone mode not supported')
+    if not can_do_wasm2c(self):
+      return self.skipTest('wasm2c not supported')
     self.set_setting('STANDALONE_WASM')
     self.set_setting('WASM2C')
     self.set_setting('WASM2C_SANDBOXING', mode)