Enable growable shared array buffers

Currently this is still behind a flag so we never turn it on by default.

Fixes: #24287

Author: sbc100

.circleci/config.yml

@@ -320,7 +320,7 @@ commands:
             CHROME_FLAGS_BASE: "--no-first-run -start-maximized --no-sandbox --use-gl=swiftshader --user-data-dir=/tmp/chrome-emscripten-profile --enable-experimental-web-platform-features --enable-features=JavaScriptSourcePhaseImports"
             # Increase the window size to avoid flaky sdl tests see #24236.
             CHROME_FLAGS_HEADLESS: "--headless=new --window-size=1024,768 --remote-debugging-port=1234"
-            CHROME_FLAGS_WASM: "--enable-experimental-webassembly-features --js-flags=\"--experimental-wasm-stack-switching --experimental-wasm-type-reflection\""
+            CHROME_FLAGS_WASM: "--enable-experimental-webassembly-features --js-flags=\"--experimental-wasm-stack-switching --experimental-wasm-type-reflection --experimental-wasm-rab-integration\""
             CHROME_FLAGS_NOCACHE: "--disk-cache-dir=/dev/null --disk-cache-size=1 --media-cache-size=1 --disable-application-cache --incognito"
             # The runners lack sound hardware so fallback to a dummy device (and
             # bypass the user gesture so audio tests work without interaction)
@@ -820,6 +820,7 @@ jobs:
             other.test_gen_struct_info
             other.test_native_call_before_init
             other.test_node_unhandled_rejection
+            other.test_pthread_growth_growable_arraybuffers
             core2.test_hello_world
             core2.test_esm_integration*
             core0.test_esm_integration*

src/lib/libcore.js

@@ -182,7 +182,9 @@ addToLibrary({
     try {
       // round size grow request up to wasm page size (fixed 64KB per spec)
       wasmMemory.grow({{{ toIndexType('pages') }}}); // .grow() takes a delta compared to the previous size
+#if !GROWABLE_ARRAYBUFFERS
       updateMemoryViews();
+#endif
 #if MEMORYPROFILER
       if (typeof emscriptenMemoryProfiler != 'undefined') {
         emscriptenMemoryProfiler.onMemoryResize(oldHeapSize, wasmMemory.buffer.byteLength);
@@ -320,6 +322,7 @@ addToLibrary({
 #endif // ALLOW_MEMORY_GROWTH
   },
 
+#if !GROWABLE_ARRAYBUFFERS
   // Called after wasm grows memory. At that time we need to update the views.
   // Without this notification, we'd need to check the buffer in JS every time
   // we return from any wasm, which adds overhead. See
@@ -330,6 +333,7 @@ addToLibrary({
 #endif
     updateMemoryViews();
   },
+#endif
 
   _emscripten_system: (command) => {
 #if ENVIRONMENT_MAY_BE_NODE

src/runtime_common.js

@@ -12,7 +12,7 @@
 #include "runtime_safe_heap.js"
 #endif
 
-#if SHARED_MEMORY && ALLOW_MEMORY_GROWTH
+#if SHARED_MEMORY && ALLOW_MEMORY_GROWTH && !GROWABLE_ARRAYBUFFERS
 #include "growableHeap.js"
 #endif
 
@@ -132,7 +132,11 @@ var runtimeExited = false;
 }}}
 
 function updateMemoryViews() {
+#if GROWABLE_ARRAYBUFFERS
+  var b = wasmMemory.toResizableBuffer();
+#else
   var b = wasmMemory.buffer;
+#endif
   {{{ maybeExportHeap('HEAP8')   }}}HEAP8 = new Int8Array(b);
   {{{ maybeExportHeap('HEAP16')  }}}HEAP16 = new Int16Array(b);
   {{{ maybeExportHeap('HEAPU8')  }}}HEAPU8 = new Uint8Array(b);

src/settings.js

@@ -2184,6 +2184,11 @@ var WASM_ESM_INTEGRATION = false;
 // [link]
 var JS_BASE64_API = false;
 
+// Enable support for GrowableSharedArrayBuffer.
+// This features is only available behind a flag in recent versions of
+// node/chrome.
+var GROWABLE_ARRAYBUFFERS = false;
+
 // Experimental support for WebAssembly js-types proposal.
 // It's currently only available under a flag in certain browsers,
 // so we disable it by default to save on code size.

system/lib/standalone/standalone.c

@@ -124,7 +124,7 @@ size_t emscripten_get_heap_max() {
 }
 
 int emscripten_resize_heap(size_t size) {
-#if defined(EMSCRIPTEN_MEMORY_GROWTH)
+#if defined(EMSCRIPTEN_REPORT_MEMORY_GROWTH)
   size_t old_size = __builtin_wasm_memory_size(0) * WASM_PAGE_SIZE;
   assert(old_size < size);
   ssize_t diff = (size - old_size + WASM_PAGE_SIZE - 1) / WASM_PAGE_SIZE;

test/test_browser.py

@@ -4728,6 +4728,7 @@ def test_pthread_hello_thread(self, opts, modularize):
   # Tests that a pthreads build of -sMINIMAL_RUNTIME works well in different build modes
   @parameterized({
     '': ([],),
+    'growable_arraybuffers': (['-sGROWABLE_ARRAYBUFFERS'],),
     'modularize': (['-sMODULARIZE', '-sEXPORT_NAME=MyModule'],),
     'O3': (['-O3'],),
     'O3_modularize': (['-O3', '-sMODULARIZE', '-sEXPORT_NAME=MyModule'],),
@@ -4739,6 +4740,7 @@ def test_minimal_runtime_hello_thread(self, opts):
   # Tests memory growth in pthreads mode, but still on the main thread.
   @parameterized({
     '': ([], 1),
+    'growable_arraybuffers': (['-sGROWABLE_ARRAYBUFFERS'], 1),
     'proxy': (['-sPROXY_TO_PTHREAD', '-sEXIT_RUNTIME'], 2),
   })
   @no_2gb('uses INITIAL_MEMORY')

test/test_other.py

@@ -14285,22 +14285,30 @@ def test_pthread_kill(self):
   @node_pthreads
   @parameterized({
     '': ([], 1),
+    'growable_arraybuffers': (['-sGROWABLE_ARRAYBUFFERS'], 1),
     'proxy': (['-sPROXY_TO_PTHREAD', '-sEXIT_RUNTIME'], 2),
   })
   def test_pthread_growth_mainthread(self, cflags, pthread_pool_size):
+    if '-sGROWABLE_ARRAYBUFFERS' in cflags:
+      self.node_args.append('--experimental-wasm-rab-integration')
+      self.require_node_canary()
     self.set_setting('PTHREAD_POOL_SIZE', pthread_pool_size)
     self.do_runf('pthread/test_pthread_memory_growth_mainthread.c', cflags=['-Wno-pthreads-mem-growth', '-pthread', '-sALLOW_MEMORY_GROWTH', '-sINITIAL_MEMORY=32MB', '-sMAXIMUM_MEMORY=256MB'] + cflags)
 
   # Tests memory growth in a pthread.
   @node_pthreads
   @parameterized({
     '': ([],),
+    'growable_arraybuffers': (['-sGROWABLE_ARRAYBUFFERS'],),
     'assert': (['-sASSERTIONS'],),
     'proxy': (['-sPROXY_TO_PTHREAD', '-sEXIT_RUNTIME'], 2),
     'minimal': (['-sMINIMAL_RUNTIME', '-sMODULARIZE', '-sEXPORT_NAME=MyModule'],),
   })
   def test_pthread_growth(self, cflags, pthread_pool_size = 1):
     self.set_setting('PTHREAD_POOL_SIZE', pthread_pool_size)
+    if '-sGROWABLE_ARRAYBUFFERS' in cflags:
+      self.node_args.append('--experimental-wasm-rab-integration')
+      self.require_node_canary()
     self.do_runf('pthread/test_pthread_memory_growth.c', cflags=['-Wno-pthreads-mem-growth', '-pthread', '-sALLOW_MEMORY_GROWTH', '-sINITIAL_MEMORY=32MB', '-sMAXIMUM_MEMORY=256MB'] + cflags)
 
   @node_pthreads

tools/building.py

@@ -1059,6 +1059,7 @@ def little_endian_heap(js_file):
 
 
 def apply_wasm_memory_growth(js_file):
+  assert not settings.GROWABLE_ARRAYBUFFERS
   logger.debug('supporting wasm memory growth with pthreads')
   return acorn_optimizer(js_file, ['growableHeap'])
 

tools/link.py

@@ -509,7 +509,7 @@ def setup_pthreads():
       diagnostics.warning('experimental', '-sMAIN_MODULE + pthreads is experimental')
     elif settings.LINKABLE:
       diagnostics.warning('experimental', '-sLINKABLE + pthreads is experimental')
-  if settings.ALLOW_MEMORY_GROWTH:
+  if settings.ALLOW_MEMORY_GROWTH and not settings.GROWABLE_ARRAYBUFFERS:
     diagnostics.warning('pthreads-mem-growth', '-pthread + ALLOW_MEMORY_GROWTH may run non-wasm code slowly, see https://github.com/WebAssembly/design/issues/1271')
 
   default_setting('DEFAULT_PTHREAD_STACK_SIZE', settings.STACK_SIZE)
@@ -795,6 +795,9 @@ def phase_linker_setup(options, linker_args):  # noqa: C901, PLR0912, PLR0915
   if settings.JS_BASE64_API:
     diagnostics.warning('experimental', '-sJS_BASE64_API is still experimental and not yet supported in browsers')
 
+  if settings.GROWABLE_ARRAYBUFFERS:
+    diagnostics.warning('experimental', '-sGROWABLE_ARRAYBUFFERS is still experimental and not yet supported in browsers')
+
   if settings.SOURCE_PHASE_IMPORTS:
     if not settings.EXPORT_ES6:
       exit_with_error('SOURCE_PHASE_IMPORTS requires EXPORT_ES6')
@@ -2330,7 +2333,7 @@ def phase_binaryen(target, options, wasm_target):
     # unsigning pass.
     # we also must do this after the asan or safe_heap instrumentation, as they
     # wouldn't be able to recognize patterns produced by the growth pass.
-    if settings.SHARED_MEMORY and settings.ALLOW_MEMORY_GROWTH:
+    if settings.SHARED_MEMORY and settings.ALLOW_MEMORY_GROWTH and not settings.GROWABLE_ARRAYBUFFERS:
       with ToolchainProfiler.profile_block('apply_wasm_memory_growth'):
         final_js = building.apply_wasm_memory_growth(final_js)
 

tools/system_libs.py

@@ -2216,7 +2216,7 @@ def get_cflags(self):
     cflags = super().get_cflags()
     cflags += ['-DNDEBUG', '-DEMSCRIPTEN_STANDALONE_WASM']
     if self.is_mem_grow:
-      cflags += ['-DEMSCRIPTEN_MEMORY_GROWTH']
+      cflags += ['-DEMSCRIPTEN_REPORT_MEMORY_GROWTH']
     if self.is_pure:
       cflags += ['-DEMSCRIPTEN_PURE_WASI']
     if self.nocatch:
@@ -2230,7 +2230,7 @@ def vary_on(cls):
   @classmethod
   def get_default_variation(cls, **kwargs):
     return super().get_default_variation(
-      is_mem_grow=settings.ALLOW_MEMORY_GROWTH,
+      is_mem_grow=settings.ALLOW_MEMORY_GROWTH and not settings.GROWABLE_ARRAYBUFFERS,
       is_pure=settings.PURE_WASI,
       nocatch=settings.DISABLE_EXCEPTION_CATCHING and not settings.WASM_EXCEPTIONS,
       **kwargs,