[wasm] Grow memory should return -1 on failure.

test/mjsunit/wasm/grow-memory.js

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Flags: --expose-wasm --expose-gc --stress-compaction
 
 load("test/mjsunit/wasm/wasm-constants.js");
 load("test/mjsunit/wasm/wasm-module-builder.js");
 
 var kPageSize = 0x10000;
@@ skipping 23 matching lines @@
 
   for(offset = 0; offset <= (kPageSize - 4); offset++) {
     poke(20);
     assertEquals(peek(), 20);
   }
   for (offset = kPageSize - 3; offset < kPageSize + 4; offset++) {
     assertTraps(kTrapMemOutOfBounds, poke);
     assertTraps(kTrapMemOutOfBounds, peek);
   }
 
-  try {
-    assertEquals(growMem(3), 1);
-  } catch (e) {
-    assertEquals("object", typeof e);
-    assertEquals(e.message, kTrapMsgs[kTrapMemAllocationFail]);
-    return;
-  }
+  var result = growMem(3);
+  assertTrue(result === 1 || result === -1);

[ahaas, 2016/08/04 07:17:34]

What do you actually assert here? Should growMem fail and return -1, or should
it succeed and return 1? I think it would be better to check just for one of
these outcomes.

[gdeepti, 2016/08/04 16:12:43]

The intent here was to reduce flakiness due to allocation failures but I see the
inconsistency here. This happens on windows 32 bit when memory is grown by a
larger number of pages repeatedly during GC stress tests. Removed for now I'll
add a return on failure instead of the check above if this test actually does
turn out to be flaky. 

 
   for (offset = kPageSize; offset <= 4*kPageSize -4; offset++) {
     poke(20);
     assertEquals(peek(), 20);
   }
   for (offset = 4*kPageSize - 3; offset < 4*kPageSize + 4; offset++) {
     assertTraps(kTrapMemOutOfBounds, poke);
     assertTraps(kTrapMemOutOfBounds, peek);
   }
 
-  try {
-    assertEquals(growMem(15), 4);
-  } catch (e) {
-    assertEquals("object", typeof e);
-    assertEquals(e.message, kTrapMsgs[kTrapMemAllocationFail]);
-    return;
-  }
+  var result = growMem(15);
+  assertTrue(result === 4 || result === -1);

[ahaas, 2016/08/04 07:17:34]

Same here.

 
   for (offset = 4*kPageSize - 3; offset <= 4*kPageSize + 4; offset++) {
     poke(20);
     assertEquals(peek(), 20);
   }
   for (offset = 19*kPageSize - 10; offset <= 19*kPageSize - 4; offset++) {
     poke(20);
     assertEquals(peek(), 20);
   }
   for (offset = 19*kPageSize - 3; offset < 19*kPageSize + 5; offset++) {
     assertTraps(kTrapMemOutOfBounds, poke);
     assertTraps(kTrapMemOutOfBounds, peek);
   }
 }
 
 testGrowMemoryReadWrite();
 
 function testGrowMemoryZeroInitialSize() {
   var builder = genGrowMemoryBuilder();
   var module = builder.instantiate();
   var offset;
   function peek() { return module.exports.load(offset); }
   function poke(value) { return module.exports.store(offset, value); }
   function growMem(pages) { return module.exports.grow_memory(pages); }
 
   assertTraps(kTrapMemOutOfBounds, peek);
   assertTraps(kTrapMemOutOfBounds, poke);
 
-  try {
-    assertEquals(growMem(1), 0);
-  } catch (e) {
-    assertEquals("object", typeof e);
-    assertEquals(e.message, kTrapMsgs[kTrapMemAllocationFail]);
-    return;
-  }
+  var result = growMem(1);
+  assertTrue(result === 0 || result === -1);

[ahaas, 2016/08/04 07:17:34]

Same here.

 
   for(offset = 0; offset <= kPageSize - 4; offset++) {
     poke(20);
     assertEquals(peek(), 20);
   }
 
   //TODO(gdeepti): Fix tests with correct write boundaries
   //when runtime function is fixed.
   for(offset = kPageSize; offset <= kPageSize + 5; offset++) {
     assertTraps(kTrapMemOutOfBounds, peek);
   }
 }
 
 testGrowMemoryZeroInitialSize();
 
 function testGrowMemoryTrapMaxPagesZeroInitialMemory() {
   var builder = genGrowMemoryBuilder();
   var module = builder.instantiate();
   var maxPages = 16385;
-  function growMem() { return module.exports.grow_memory(maxPages); }
-  assertTraps(kTrapMemOutOfBounds, growMem);
+  function growMem(pages) { return module.exports.grow_memory(pages); }
+  assertEquals(growMem(maxPages), -1);
 }
 
 testGrowMemoryTrapMaxPagesZeroInitialMemory();
 
 function testGrowMemoryTrapMaxPages() {
   var builder = genGrowMemoryBuilder();
   builder.addMemory(1, 1, false);
   var module = builder.instantiate();
   var maxPages = 16384;
-  function growMem() { return module.exports.grow_memory(maxPages); }
-  assertTraps(kTrapMemOutOfBounds, growMem);
+  function growMem(pages) { return module.exports.grow_memory(pages); }
+  assertEquals(growMem(maxPages), -1);
 }
 
 testGrowMemoryTrapMaxPages();