[tests] Speed up mjsunit/packed-elements by 1500x

Adding a %SimulateNewspaceFull runtime function speeds up this test
from 7m21s to 0.3s (on arm.optdebug with --jitless).
Bonus content:
- speed up mjsunit/md5 by 23x (5m25s -> 7.5s)
- speed up mjsunit/string-replace-gc by 8x (1m37s -> 12s)

Bug: v8:9700, v8:9396
Change-Id: Id00d0b83b51192edf1d5493b49b79b5d76e78087
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1807355
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63829}

src/runtime/runtime-test.cc

@@ -677,6 +677,46 @@ RUNTIME_FUNCTION(Runtime_SetAllocationTimeout) {
   return ReadOnlyRoots(isolate).undefined_value();
 }
 
+namespace {
+
+int FixedArrayLenFromSize(int size) {
+  return Min((size - FixedArray::kHeaderSize) / kTaggedSize,
+             FixedArray::kMaxRegularLength);
+}
+
+void FillUpOneNewSpacePage(Isolate* isolate, Heap* heap) {
+  NewSpace* space = heap->new_space();
+  int space_remaining = static_cast<int>(*space->allocation_limit_address() -
+                                         *space->allocation_top_address());
+  while (space_remaining > 0) {
+    int length = FixedArrayLenFromSize(space_remaining);
+    if (length > 0) {
+      Handle<FixedArray> padding =
+          isolate->factory()->NewFixedArray(length, AllocationType::kYoung);
+      DCHECK(heap->new_space()->Contains(*padding));
+      space_remaining -= padding->Size();
+    } else {
+      // Not enough room to create another fixed array. Create a filler.
+      heap->CreateFillerObjectAt(*heap->new_space()->allocation_top_address(),
+                                 space_remaining, ClearRecordedSlots::kNo);
+      break;
+    }
+  }
+}
+
+}  // namespace
+
+RUNTIME_FUNCTION(Runtime_SimulateNewspaceFull) {
+  HandleScope scope(isolate);
+  Heap* heap = isolate->heap();
+  NewSpace* space = heap->new_space();
+  PauseAllocationObserversScope pause_observers(heap);
+  do {
+    FillUpOneNewSpacePage(isolate, heap);
+  } while (space->AddFreshPage());
+
+  return ReadOnlyRoots(isolate).undefined_value();
+}
 
 RUNTIME_FUNCTION(Runtime_DebugPrint) {
   SealHandleScope shs(isolate);

src/runtime/runtime.h

@@ -515,6 +515,7 @@ namespace internal {
   F(SetWasmCompileControls, 2, 1)             \
   F(SetWasmInstantiateControls, 0, 1)         \
   F(SetWasmThreadsEnabled, 1, 1)              \
+  F(SimulateNewspaceFull, 0, 1)               \
   F(StringIteratorProtector, 0, 1)            \
   F(SystemBreak, 0, 1)                        \
   F(TraceEnter, 0, 1)                         \

test/cctest/heap/heap-utils.cc

@@ -98,11 +98,15 @@ std::vector<Handle<FixedArray>> CreatePadding(Heap* heap, int padding_size,
       allocate_memory = free_memory;
       length = FixedArrayLenFromSize(allocate_memory);
       if (length <= 0) {
-        // Not enough room to create another fixed array. Let's create a filler.
-        if (free_memory > (2 * kTaggedSize)) {
+        // Not enough room to create another FixedArray, so create a filler.
+        if (allocation == i::AllocationType::kOld) {
           heap->CreateFillerObjectAt(
               *heap->old_space()->allocation_top_address(), free_memory,
               ClearRecordedSlots::kNo);
+        } else {
+          heap->CreateFillerObjectAt(
+              *heap->new_space()->allocation_top_address(), free_memory,
+              ClearRecordedSlots::kNo);
         }
         break;
       }
@@ -127,8 +131,9 @@ void AllocateAllButNBytes(v8::internal::NewSpace* space, int extra_bytes,
   if (new_linear_size == 0) return;
   std::vector<Handle<FixedArray>> handles = heap::CreatePadding(
       space->heap(), new_linear_size, i::AllocationType::kYoung);
-  if (out_handles != nullptr)
+  if (out_handles != nullptr) {
     out_handles->insert(out_handles->end(), handles.begin(), handles.end());
+  }
 }
 
 void FillCurrentPage(v8::internal::NewSpace* space,
@@ -144,8 +149,9 @@ bool FillUpOnePage(v8::internal::NewSpace* space,
   if (space_remaining == 0) return false;
   std::vector<Handle<FixedArray>> handles = heap::CreatePadding(
       space->heap(), space_remaining, i::AllocationType::kYoung);
-  if (out_handles != nullptr)
+  if (out_handles != nullptr) {
     out_handles->insert(out_handles->end(), handles.begin(), handles.end());
+  }
   return true;
 }
 

test/cctest/heap/test-compaction.cc

@@ -84,6 +84,18 @@ HEAP_TEST(CompactionFullAbortedPage) {
   }
 }
 
+namespace {
+
+int GetObjectSize(int objects_per_page) {
+  int allocatable =
+      static_cast<int>(MemoryChunkLayout::AllocatableMemoryInDataPage());
+  // Make sure that object_size is a multiple of kTaggedSize.
+  int object_size =
+      ((allocatable / kTaggedSize) / objects_per_page) * kTaggedSize;
+  return Min(kMaxRegularHeapObjectSize, object_size);
+}
+
+}  // namespace
 
 HEAP_TEST(CompactionPartiallyAbortedPage) {
   if (FLAG_never_compact) return;
@@ -96,10 +108,7 @@ HEAP_TEST(CompactionPartiallyAbortedPage) {
   FLAG_manual_evacuation_candidates_selection = true;
 
   const int objects_per_page = 10;
-  const int object_size =
-      Min(kMaxRegularHeapObjectSize,
-          static_cast<int>(MemoryChunkLayout::AllocatableMemoryInDataPage()) /
-              objects_per_page);
+  const int object_size = GetObjectSize(objects_per_page);
 
   CcTest::InitializeVM();
   Isolate* isolate = CcTest::i_isolate();
@@ -176,10 +185,7 @@ HEAP_TEST(CompactionPartiallyAbortedPageIntraAbortedPointers) {
   FLAG_manual_evacuation_candidates_selection = true;
 
   const int objects_per_page = 10;
-  const int object_size =
-      Min(kMaxRegularHeapObjectSize,
-          static_cast<int>(MemoryChunkLayout::AllocatableMemoryInDataPage()) /
-              objects_per_page);
+  const int object_size = GetObjectSize(objects_per_page);
 
   CcTest::InitializeVM();
   Isolate* isolate = CcTest::i_isolate();
@@ -270,10 +276,7 @@ HEAP_TEST(CompactionPartiallyAbortedPageWithStoreBufferEntries) {
   FLAG_manual_evacuation_candidates_selection = true;
 
   const int objects_per_page = 10;
-  const int object_size =
-      Min(kMaxRegularHeapObjectSize,
-          static_cast<int>(MemoryChunkLayout::AllocatableMemoryInDataPage()) /
-              objects_per_page);
+  const int object_size = GetObjectSize(objects_per_page);
 
   CcTest::InitializeVM();
   Isolate* isolate = CcTest::i_isolate();

test/mjsunit/md5.js

@@ -201,11 +201,9 @@ To know our further pleasure in this case,\n\
 To old Free-town, our common judgment-place.\n\
 Once more, on pain of death, all men depart.\n"
 
-for (var i = 0; i < 4; ++i) {
+for (var i = 0; i < 2; ++i) {
   plainText += plainText;
 }
 
-assertEquals(hex_md5("abc"), "900150983cd24fb0d6963f7d28e17f72");
-for (var i = 0; i < 11; ++i) {
-  assertEquals(hex_md5(plainText), "1b8719c72d5d8bfd06e096ef6c6288c5");
-}
+assertEquals("900150983cd24fb0d6963f7d28e17f72", hex_md5("abc"));
+assertEquals("6c843ffbdd773e88ae4ac4a5df79a784", hex_md5(plainText));

test/mjsunit/mjsunit.status

@@ -295,7 +295,6 @@
   'compare-known-objects-slow': [SKIP],
   'compiler/array-multiple-receiver-maps': [SKIP],
   # Tests taking too long
-  'packed-elements': [SKIP],
   'regress/regress-1122': [SKIP],
   'regress/regress-331444': [SKIP],
   'regress/regress-353551': [SKIP],
@@ -486,7 +485,6 @@
   'math-floor-of-div-nosudiv': [PASS, SLOW],
   'math-floor-of-div': [PASS, SLOW],
   'messages': [PASS, SLOW],
-  'packed-elements': [PASS, SLOW],
   'regress/regress-2790': [PASS, SLOW],
   'regress/regress-331444': [PASS, SLOW],
   'regress/regress-490': [PASS, SLOW],
@@ -525,7 +523,6 @@
 
   # Pass but take too long with the simulator in debug mode.
   'array-sort': [PASS, SLOW],
-  'packed-elements': [SKIP],
   'regexp-global': [SKIP],
   'math-floor-of-div': [PASS, SLOW],
   'math-floor-of-div-nosudiv': [PASS, SLOW],
@@ -660,7 +657,6 @@
   # Slow tests.
   'array-sort': [PASS, SLOW],
   'compiler/osr-with-args': [PASS, SLOW],
-  'packed-elements': [PASS, SLOW],
   'regress/regress-2790': [PASS, SLOW],
   'regress/regress-91008': [PASS, SLOW],
   'regress/regress-json-stringify-gc': [PASS, SLOW],
@@ -944,7 +940,6 @@
   'regress/regress-crbug-482998': [PASS, SLOW],
   'regress/regress-91008': [PASS, SLOW],
   'regress/regress-779407': [PASS, SLOW],
-  'packed-elements': [PASS, SLOW],
   'harmony/regexp-property-lu-ui': [PASS, SLOW],
   'whitespaces': [PASS, SLOW],
   'generated-transition-stub': [PASS, SLOW],
@@ -1017,10 +1012,8 @@
 }],  # variant == stress and (arch == arm or arch == arm64) and simulator_run
 
 ##############################################################################
-['variant == nooptimization and (arch == arm or arch == arm64) and simulator_run', {
+['variant in (nooptimization, jitless) and arch in (arm, arm64) and simulator_run', {
   # Slow tests: https://crbug.com/v8/7783
-  'md5': [SKIP],
-  'packed-elements': [SKIP],
   'regress/regress-crbug-319860': [SKIP],
   'wasm/asm-wasm-f32': [SKIP],
   'wasm/asm-wasm-f64': [SKIP],

test/mjsunit/packed-elements.js

@@ -92,12 +92,15 @@ function test6() {
 }
 
 function test_with_optimization(f) {
-  // Run tests in a loop to make sure that inlined Array() constructor runs out
-  // of new space memory and must fall back on runtime impl.
   %PrepareFunctionForOptimization(f);
-  for (i = 0; i < 25000; ++i) f();
+  for (i = 0; i < 3; ++i) f();
+  // Cause the inlined Array() constructor to fall back to the runtime impl.
+  %SimulateNewspaceFull();
+  f();
   %OptimizeFunctionOnNextCall(f);
-  for (i = 0; i < 25000; ++i) f(); // Make sure GC happens
+  f();
+  %SimulateNewspaceFull();  // Make sure GC happens.
+  f();
 }
 
 test_with_optimization(test1);

test/mjsunit/string-replace-gc.js

@@ -25,31 +25,22 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-//
-// Regression test for the r1512 fix.
+// Regression test for the r1513 fix.
+
+// Flags: --allow-natives-syntax
 
 var foo = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
+assertEquals(39, foo.length);
 
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
-foo = foo + foo;
+for (var i = 0; i < 12; i++) {
+  foo = foo + foo;
+}
 
-foo.replace(/[b]/, "c");  // Flatten foo.
+foo = %FlattenString(foo);
 
 var moving_string = "b" + "c";
 
-var bar = foo.replace(/[a]/g, moving_string);
+var bar = foo.replace(/a/g, moving_string);
 
-print(bar.length);
+// 39 * 2^12 * 2
+assertEquals(319488, bar.length);