Add runtime detection for toResizableBuffer. NFC

.circleci/config.yml

@@ -1059,6 +1059,7 @@ jobs:
             other.test_min_node_version
             other.test_node_emscripten_num_logical_cores
             other.test_js_base64_api
+            other.test_memory_growth
             core2.test_hello_world
             core2.test_pthread_create
             core2.test_i64_invoke_bigint

src/runtime_common.js

@@ -108,11 +108,37 @@ var runtimeExited = false;
   };
 }}}
 
+#if ALLOW_MEMORY_GROWTH
+var resizeableMemoryBuffer = 0;
+#endif
+
 function updateMemoryViews() {
+#if RUNTIME_DEBUG
+  dbg(`updateMemoryViews: initial=${!HEAP8} size=${wasmMemory.buffer.byteLength}`);
+#endif
+#if ALLOW_MEMORY_GROWTH
+  if (resizeableMemoryBuffer) {
+    // If we already have a heap that is resizeable we
+    // don't need to do anything in updateMemoryViews.
+    return;
+  }
 #if GROWABLE_ARRAYBUFFERS
   var b = wasmMemory.toResizableBuffer();
 #else
   var b = wasmMemory.buffer;
+  try {
+    // This method may be missing or could fail with `Memory must have a maximum`
+    b = wasmMemory.toResizableBuffer();
+    resizeableMemoryBuffer = true;
+  } catch {}
+#endif
+#else
+#if ASSERTIONS
+  // When memory growth is disabled this function should be called
+  // exacltly once.
+  assert(!HEAP8, 'updateMemoryViews should only be called once when ALLOW_MEMORY_GROWTH=0');
+#endif
+  var b = wasmMemory.buffer;
 #endif
   {{{ maybeExportHeap('HEAP8')   }}}HEAP8 = new Int8Array(b);
   {{{ maybeExportHeap('HEAP16')  }}}HEAP16 = new Int16Array(b);

test/codesize/test_codesize_hello_O0.json

@@ -1,10 +1,10 @@
 {
-  "a.out.js": 23248,
-  "a.out.js.gz": 8396,
+  "a.out.js": 23344,
+  "a.out.js.gz": 8443,
   "a.out.nodebug.wasm": 15115,
   "a.out.nodebug.wasm.gz": 7464,
-  "total": 38363,
-  "total_gz": 15860,
+  "total": 38459,
+  "total_gz": 15907,
   "sent": [
     "fd_write"
   ],

test/codesize/test_codesize_mem_O3_grow.json

@@ -1,10 +1,10 @@
 {
-  "a.out.js": 4541,
-  "a.out.js.gz": 2193,
+  "a.out.js": 4595,
+  "a.out.js.gz": 2221,
   "a.out.nodebug.wasm": 5261,
   "a.out.nodebug.wasm.gz": 2419,
-  "total": 9802,
-  "total_gz": 4612,
+  "total": 9856,
+  "total_gz": 4640,
   "sent": [
     "a (emscripten_resize_heap)"
   ],

test/codesize/test_codesize_mem_O3_grow_standalone.json

@@ -1,10 +1,10 @@
 {
-  "a.out.js": 4012,
-  "a.out.js.gz": 1933,
+  "a.out.js": 4064,
+  "a.out.js.gz": 1956,
   "a.out.nodebug.wasm": 5641,
   "a.out.nodebug.wasm.gz": 2659,
-  "total": 9653,
-  "total_gz": 4592,
+  "total": 9705,
+  "total_gz": 4615,
   "sent": [
     "args_get",
     "args_sizes_get",

test/codesize/test_codesize_minimal_O0.expected.js

@@ -465,6 +465,9 @@ var runtimeInitialized = false;
 
 
 function updateMemoryViews() {
+  // When memory growth is disabled this function should be called
+  // exacltly once.
+  assert(!HEAP8, 'updateMemoryViews should only be called once when ALLOW_MEMORY_GROWTH=0');
   var b = wasmMemory.buffer;
   HEAP8 = new Int8Array(b);
   HEAP16 = new Int16Array(b);

test/codesize/test_codesize_minimal_O0.json

@@ -1,10 +1,10 @@
 {
-  "a.out.js": 18596,
-  "a.out.js.gz": 6718,
+  "a.out.js": 18687,
+  "a.out.js.gz": 6766,
   "a.out.nodebug.wasm": 1015,
   "a.out.nodebug.wasm.gz": 602,
-  "total": 19611,
-  "total_gz": 7320,
+  "total": 19702,
+  "total_gz": 7368,
   "sent": [],
   "imports": [],
   "exports": [

test/codesize/test_codesize_minimal_pthreads_memgrowth.json

@@ -1,10 +1,10 @@
 {
-  "a.out.js": 7357,
-  "a.out.js.gz": 3627,
+  "a.out.js": 7416,
+  "a.out.js.gz": 3658,
   "a.out.nodebug.wasm": 19064,
   "a.out.nodebug.wasm.gz": 8804,
-  "total": 26421,
-  "total_gz": 12431,
+  "total": 26480,
+  "total_gz": 12462,
   "sent": [
     "a (memory)",
     "b (exit)",

test/codesize/test_unoptimized_code_size.json

@@ -1,16 +1,16 @@
 {
-  "hello_world.js": 54902,
-  "hello_world.js.gz": 17283,
+  "hello_world.js": 55082,
+  "hello_world.js.gz": 17353,
   "hello_world.wasm": 15115,
   "hello_world.wasm.gz": 7464,
   "no_asserts.js": 25903,
   "no_asserts.js.gz": 8768,
   "no_asserts.wasm": 12229,
   "no_asserts.wasm.gz": 6004,
-  "strict.js": 52659,
-  "strict.js.gz": 16513,
+  "strict.js": 52839,
+  "strict.js.gz": 16584,
   "strict.wasm": 15115,
-  "strict.wasm.gz": 7457,
-  "total": 175923,
-  "total_gz": 63489
+  "strict.wasm.gz": 7461,
+  "total": 176283,
+  "total_gz": 63634
 }

test/common.py

@@ -332,6 +332,14 @@ def get_deno():
   return get_engine(engine_is_deno)
 
 
+def check_node_version(major, minor=0, revision=0):
+  nodejs = get_nodejs()
+  if not nodejs:
+    return False
+  version = shared.get_node_version(nodejs)
+  return version >= (major, minor, revision)
+
+
 def clean_js_output(output):
   """Cleanup the JS output prior to running verification steps on it.
 
@@ -532,14 +540,10 @@ def require_wasm64(self):
     self.fail('either d8, node >= 24 or deno required to run wasm64 tests.  Use EMTEST_SKIP_WASM64 to skip')
 
   def try_require_node_version(self, major, minor=0, revision=0):
-    nodejs = get_nodejs()
-    if not nodejs:
-      return False
-    version = shared.get_node_version(nodejs)
-    if version < (major, minor, revision):
+    if not check_node_version(major, minor, revision):
       return False
 
-    self.require_engine(nodejs)
+    self.require_engine(get_nodejs())
     return True
 
   def require_wasm_legacy_eh(self):

test/test_other.py

@@ -42,6 +42,7 @@
   TEST_ROOT,
   WEBIDL_BINDER,
   RunnerCore,
+  check_node_version,
   copy_asset,
   copytree,
   create_file,
@@ -6426,28 +6427,36 @@ def test_file_packager_huge(self):
     self.assertContained(MESSAGE, err)
     self.clear()
 
-  @parameterized({
-    '': (True,),
-    'wasm2js': (False,),
-  })
-  def test_massive_alloc(self, wasm):
+  @also_with_wasm2js
+  def test_memory_growth(self):
     create_file('main.c', r'''
-#include <stdio.h>
+#include <assert.h>
 #include <stdlib.h>
+#include <string.h>
+#include <emscripten/em_asm.h>
+#include <emscripten/console.h>
 
 int main() {
-  volatile long x = (long)malloc(1024 * 1024 * 1400);
-  return x == 0; // can't alloc it, but don't fail catastrophically, expect null
+  // Report whether we are running with `toResizableBuffer` enabled.
+  EM_ASM(out('resizable memory buffers:', Boolean(wasmMemory.toResizableBuffer)));
+
+  void* x = malloc(256 * 1024 * 1024);
+  assert(x != NULL);
+  // Have JS use some of the memory expanded range
+  char* str = (char*)x - 100;
+  strcpy(str, "Hello, world!");
+  emscripten_out(str);
+  return 0;
 }
-    ''')
-    cmd = [EMCC, 'main.c', '-sALLOW_MEMORY_GROWTH', '-sINITIAL_MEMORY=16MB']
-    if not wasm:
-      cmd += ['-sWASM=0']
-    self.run_process(cmd)
-    # just care about message regarding allocating over 1GB of memory
-    output = self.run_js('a.out.js')
-    if not wasm:
-      self.assertContained('Warning: Enlarging memory arrays, this is not fast! 16777216,1468137472\n', output)
+''')
+    output = self.do_runf('main.c', 'Hello, world!\n', cflags=['-sALLOW_MEMORY_GROWTH'])
+    if self.is_wasm2js():
+      self.assertContained('Warning: Enlarging memory arrays, this is not fast! 16908288,268566528\n', output)
+
+    if check_node_version(26):
+      self.assertContained('resizable memory buffers: true\n', output)
+    else:
+      self.assertContained('resizable memory buffers: false\n', output)
 
   @also_with_wasm2js
   @parameterized({

tools/acorn-optimizer.mjs

@@ -1091,7 +1091,7 @@ function growableHeap(ast) {
       if (
         !(
           node.id.type === 'Identifier' &&
-          (node.id.name === 'growMemViews' || node.id.name === 'LE_HEAP_UPDATE')
+          (node.id.name === 'growMemViews' || node.id.name === 'updateMemoryViews' || node.id.name === 'LE_HEAP_UPDATE')
         )
       ) {
         c(node.body);

tools/link.py

@@ -1049,6 +1049,7 @@ def limit_incoming_module_api():
 
   if settings.PURE_WASI:
     settings.STANDALONE_WASM = 1
+    settings.ALLOW_MEMORY_GROWTH = 1
     settings.WASM_BIGINT = 1
     # WASI does not support Emscripten (JS-based) exception catching, which the
     # JS-based longjmp support also uses. Emscripten EH is by default disabled