browser gc test

src/library_gc.js

@@ -18,7 +18,7 @@ if (GC_SUPPORT) {
         GC.initted = true;
 #if GENERATING_HTML
         setInterval(function() {
-          GC.maybeGC();
+          GC.maybeCollect();
         }, 1000);
 #else
         // No HTML intervals, so you need to call GC.maybeCollect() or GC.collect() manually

src/settings.js

@@ -216,7 +216,7 @@ var FAKE_X86_FP80 = 1; // Replaces x86_fp80 with double. This loses precision. I
                        // if you can, to get the original source code to build without x86_fp80
                        // (which is nonportable anyhow).
 
-var GC_SUPPORT = 0; // Enables GC, see gc.h
+var GC_SUPPORT = 1; // Enables GC, see gc.h (this does not add overhead, so it is on by default)
 
 // Compiler debugging options
 var DEBUG_TAGS_SHOWING = [];

tests/browser_gc.cpp

@@ -0,0 +1,96 @@
+#include <stdio.h>
+#include <gc.h>
+#include <assert.h>
+#include <emscripten.h>
+
+void *global;
+
+int freed = 0;
+
+void finalizer(void *ptr, void *arg) {
+  printf("finalizing %d (global == %d)\n", (int)arg, ptr == global);
+  freed++;
+  if (ptr == global) global = 0;
+}
+
+int stage = 0;
+float start = 0;
+
+void waiter() {
+  if (stage == 0) { // wait for a while, see no GCing
+    assert(global);
+    if (emscripten_get_now() - start > 2100) {
+      GC_MALLOC(1024*1024*2); // allocate enough to trigger a GC
+      start = emscripten_get_now();
+      stage = 1;
+      printf("stage 1\n");
+    }
+  } else if (stage == 1) {
+    assert(global);
+    if (freed > 0) {
+      GC_FREE(global);
+      stage = 2;
+      start = emscripten_get_now();
+      printf("stage 2\n");
+    }
+    if (emscripten_get_now() - start > 2100) {
+      printf("fail, too much time passed (a)\n");
+      return;
+    }
+  } else if (stage == 2) {
+    if (emscripten_get_now() - start > 2100) { // wait and see that no gc'ing happens yet
+      GC_MALLOC(1024*1024*2); // allocate enough to trigger a GC
+      stage = 3;
+      start = emscripten_get_now();
+      printf("stage 3\n");
+    }
+  } else if (stage == 3) {
+    assert(!global);
+    if (freed == 5) {
+      printf("Ok.\n");
+      int result = 1;
+      REPORT_RESULT();
+      return;
+    }
+    if (emscripten_get_now() - start > 2100) {
+      printf("fail, too much time passed (b)\n");
+      return;
+    }
+  }
+
+  emscripten_async_call(waiter, 100);
+}
+
+int main() {
+  start = emscripten_get_now();
+
+  GC_INIT();
+
+  void *local, *local2, *local3, *local4;
+
+  global = GC_MALLOC(12);
+  GC_REGISTER_FINALIZER_NO_ORDER(global, finalizer, 0, 0, 0);
+  local = GC_MALLOC(12);
+  GC_REGISTER_FINALIZER_NO_ORDER(local, finalizer, (void*)1, 0, 0);
+  local2 = GC_MALLOC_ATOMIC(12);
+  GC_REGISTER_FINALIZER_NO_ORDER(local2, finalizer, (void*)2, 0, 0);
+  local3 = GC_MALLOC(12);
+  GC_REGISTER_FINALIZER_NO_ORDER(local3, finalizer, (void*)3, 0, 0);
+  local4 = GC_MALLOC(12);
+  GC_REGISTER_FINALIZER_NO_ORDER(local4, finalizer, (void*)4, 0, 0);
+
+  void **globalData = (void**)global;
+  globalData[0] = local;
+  globalData[1] = local2;
+
+  void **localData = (void**)local;
+  localData[0] = local3;
+
+  void **local2Data = (void**)local2;
+  local2Data[0] = local4; // actually ignored, because local2 is atomic, so 4 is freeable
+
+  emscripten_async_call(waiter, 100);
+
+  return 0;
+}
+

tests/runner.py

@@ -7431,6 +7431,9 @@ def btest(self, filename, expected=None, reference=None, args=[]): # TODO: use i
     def test_emscripten_api(self):
       self.btest('emscripten_api_browser.cpp', '1')
 
+    def test_gc(self):
+      self.btest('browser_gc.cpp', '1')
+
     def test_sdlglshader(self):
       self.btest('sdlglshader.c', reference='sdlglshader.png', args=['--closure', '1'])