Revert "[heap-verification] Increase verification for arguments objects"

This reverts commit b9194e93f2.

Reason for revert: Makes old pipeline flaky with custom snapshot:
https://build.chromium.org/p/client.v8/builders/V8%20Linux64%20-%20custom%20snapshot%20-%20debug/builds/14049

Original change's description:
> [heap-verification] Increase verification for arguments objects
> 
> BUG: v8:6251
> Change-Id: I8a6dd528656a69c7910770acaf2133830b60c291
> Reviewed-on: https://chromium-review.googlesource.com/475651
> Commit-Queue: Camillo Bruni <cbruni@chromium.org>
> Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#44609}

TBR=jkummerow@chromium.org,cbruni@chromium.org,v8-reviews@googlegroups.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: Iedfdad290bf4f5f6ec2534e8c5378a7cc195db82
Reviewed-on: https://chromium-review.googlesource.com/475719
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44616}

src/objects-debug.cc

@@ -8,7 +8,6 @@
 #include "src/bootstrapper.h"
 #include "src/disasm.h"
 #include "src/disassembler.h"
-#include "src/elements.h"
 #include "src/field-type.h"
 #include "src/layout-descriptor.h"
 #include "src/macro-assembler.h"
@@ -106,14 +105,12 @@ void HeapObject::HeapObjectVerify() {
       break;
     case JS_OBJECT_TYPE:
     case JS_ERROR_TYPE:
+    case JS_ARGUMENTS_TYPE:
     case JS_API_OBJECT_TYPE:
     case JS_SPECIAL_API_OBJECT_TYPE:
     case JS_CONTEXT_EXTENSION_OBJECT_TYPE:
       JSObject::cast(this)->JSObjectVerify();
       break;
-    case JS_ARGUMENTS_TYPE:
-      JSArgumentsObject::cast(this)->JSArgumentsObjectVerify();
-      break;
     case JS_GENERATOR_OBJECT_TYPE:
       JSGeneratorObject::cast(this)->JSGeneratorObjectVerify();
       break;
@@ -165,7 +162,6 @@ void HeapObject::HeapObjectVerify() {
     case JS_MAP_ITERATOR_TYPE:
       JSMapIterator::cast(this)->JSMapIteratorVerify();
       break;
-
     case JS_TYPED_ARRAY_KEY_ITERATOR_TYPE:
     case JS_FAST_ARRAY_KEY_ITERATOR_TYPE:
     case JS_GENERIC_ARRAY_KEY_ITERATOR_TYPE:
@@ -330,7 +326,11 @@ void JSObject::JSObjectVerify() {
   VerifyHeapPointer(properties());
   VerifyHeapPointer(elements());
 
-  CHECK_IMPLIES(HasSloppyArgumentsElements(), IsJSArgumentsObject());
+  if (HasSloppyArgumentsElements()) {
+    CHECK(this->elements()->IsFixedArray());
+    CHECK_GE(this->elements()->length(), 2);
+  }
+
   if (HasFastProperties()) {
     int actual_unused_property_fields = map()->GetInObjectProperties() +
                                         properties()->length() -
@@ -474,60 +474,6 @@ void TransitionArray::TransitionArrayVerify() {
         next_link()->IsTransitionArray());
 }
 
-void JSArgumentsObject::JSArgumentsObjectVerify() {
-  VerifyObjectField(kLengthOffset);
-  if (IsSloppyArgumentsElementsKind(GetElementsKind())) {
-    JSSloppyArgumentsObject::cast(this)->JSSloppyArgumentsObjectVerify();
-  }
-  JSObjectVerify();
-}
-
-void JSSloppyArgumentsObject::JSSloppyArgumentsObjectVerify() {
-  VerifyObjectField(kCalleeOffset);
-  ElementsKind kind = GetElementsKind();
-  CHECK(IsSloppyArgumentsElementsKind(kind));
-  SloppyArgumentsElements::cast(elements())
-      ->SloppyArgumentsElementsVerify(this);
-}
-
-void SloppyArgumentsElements::SloppyArgumentsElementsVerify(
-    JSSloppyArgumentsObject* holder) {
-  Isolate* isolate = GetIsolate();
-  FixedArrayVerify();
-  // Abort verification if only partially initialized
-  if (arguments()->IsUndefined(isolate)) return;
-
-  ElementsKind kind = holder->GetElementsKind();
-  CHECK(IsFixedArray());
-  CHECK_GE(length(), 2);
-  CHECK_EQ(map(), isolate->heap()->sloppy_arguments_elements_map());
-  Context* contextObject = Context::cast(context());
-  FixedArray* argElements = FixedArray::cast(arguments());
-  if (argElements->length() == 0) {
-    CHECK(argElements == isolate->heap()->empty_fixed_array());
-    return;
-  }
-  int nofMappedParameters =
-      length() - SloppyArgumentsElements::kParameterMapStart;
-  CHECK_LE(nofMappedParameters, contextObject->length());
-  CHECK_LE(nofMappedParameters, argElements->length());
-  ElementsAccessor* accessor;
-  if (kind == FAST_SLOPPY_ARGUMENTS_ELEMENTS) {
-    accessor = ElementsAccessor::ForKind(FAST_HOLEY_ELEMENTS);
-  } else {
-    accessor = ElementsAccessor::ForKind(DICTIONARY_ELEMENTS);
-  }
-  for (int i = 0; i < nofMappedParameters; i++) {
-    // Verify that each mapped arguments is either the hole or a valid Smi
-    // within context length range.
-    Object* mapped = get_mapped_entry(i);
-    if (mapped->IsTheHole(isolate)) continue;
-    Object* value = contextObject->get(Smi::cast(mapped)->value());
-    CHECK(value->IsObject());
-    // None of the context-mapped entries should exist in the arguments elements
-    CHECK(!accessor->HasElement(holder, i, argElements));
-  }
-}
 
 void JSGeneratorObject::JSGeneratorObjectVerify() {
   // In an expression like "new g()", there can be a point where a generator

src/objects-inl.h

@@ -202,10 +202,6 @@ bool HeapObject::IsFixedArray() const {
 
 bool HeapObject::IsSloppyArgumentsElements() const { return IsFixedArray(); }
 
-bool HeapObject::IsJSSloppyArgumentsObject() const {
-  return IsJSArgumentsObject();
-}
-
 bool HeapObject::IsJSGeneratorObject() const {
   return map()->instance_type() == JS_GENERATOR_OBJECT_TYPE ||
          IsJSAsyncGeneratorObject();
@@ -636,7 +632,6 @@ CAST_ACCESSOR(Foreign)
 CAST_ACCESSOR(GlobalDictionary)
 CAST_ACCESSOR(HandlerTable)
 CAST_ACCESSOR(HeapObject)
-CAST_ACCESSOR(JSArgumentsObject);
 CAST_ACCESSOR(JSArray)
 CAST_ACCESSOR(JSArrayBuffer)
 CAST_ACCESSOR(JSArrayBufferView)
@@ -660,7 +655,6 @@ CAST_ACCESSOR(JSPromiseCapability)
 CAST_ACCESSOR(JSPromise)
 CAST_ACCESSOR(JSSet)
 CAST_ACCESSOR(JSSetIterator)
-CAST_ACCESSOR(JSSloppyArgumentsObject)
 CAST_ACCESSOR(JSAsyncFromSyncIterator)
 CAST_ACCESSOR(JSStringIterator)
 CAST_ACCESSOR(JSArrayIterator)
@@ -5456,9 +5450,6 @@ void Map::SetBackPointer(Object* value, WriteBarrierMode mode) {
   set_constructor_or_backpointer(value, mode);
 }
 
-ACCESSORS(JSArgumentsObject, length, Object, kLengthOffset);
-ACCESSORS(JSSloppyArgumentsObject, callee, Object, kCalleeOffset);
-
 ACCESSORS(Map, code_cache, FixedArray, kCodeCacheOffset)
 ACCESSORS(Map, dependent_code, DependentCode, kDependentCodeOffset)
 ACCESSORS(Map, weak_cell_cache, Object, kWeakCellCacheOffset)

src/objects.h

@@ -1011,7 +1011,6 @@ template <class C> inline bool Is(Object* obj);
   V(JSReceiver)                  \
   V(JSObject)                    \
   V(JSArgumentsObject)           \
-  V(JSSloppyArgumentsObject)     \
   V(JSContextExtensionObject)    \
   V(JSGeneratorObject)           \
   V(JSAsyncGeneratorObject)      \
@@ -2683,11 +2682,6 @@ class JSArgumentsObject: public JSObject {
   // Indices of in-object properties.
   static const int kLengthIndex = 0;
 
-  DECL_ACCESSORS(length, Object)
-
-  DECLARE_VERIFIER(JSArgumentsObject)
-  DECLARE_CAST(JSArgumentsObject)
-
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSArgumentsObject);
 };
@@ -2703,11 +2697,6 @@ class JSSloppyArgumentsObject: public JSArgumentsObject {
   // Indices of in-object properties.
   static const int kCalleeIndex = 1;
 
-  DECL_ACCESSORS(callee, Object)
-
-  DECLARE_VERIFIER(JSSloppyArgumentsObject)
-  DECLARE_CAST(JSSloppyArgumentsObject)
-
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSSloppyArgumentsObject);
 };
@@ -2720,8 +2709,6 @@ class JSStrictArgumentsObject: public JSArgumentsObject {
   // Offsets of object fields.
   static const int kSize = JSArgumentsObject::kHeaderSize;
 
-  DECLARE_CAST(JSStrictArgumentsObject)
-
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSStrictArgumentsObject);
 };
@@ -2893,7 +2880,6 @@ class FixedDoubleArray: public FixedArrayBase {
 
 // Helper class to access FAST_ and SLOW_SLOPPY_ARGUMENTS_ELEMENTS
 //
-//    SloppyArgumentsElements
 // +---+-----------------------+
 // | 0 | Context* context      |
 // +---------------------------+
@@ -2928,9 +2914,6 @@ class SloppyArgumentsElements : public FixedArray {
   inline void set_mapped_entry(uint32_t entry, Object* object);
 
   DECLARE_CAST(SloppyArgumentsElements)
-#ifdef VERIFY_HEAP
-  void SloppyArgumentsElementsVerify(JSSloppyArgumentsObject* holder);
-#endif
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(SloppyArgumentsElements);

test/mjsunit/element-read-only.js

@@ -2,23 +2,17 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --allow-natives-syntax
-
 function f(a, b, c, d) { return arguments; }
 
 // Ensure non-configurable argument elements stay non-configurable.
 (function () {
   var args = f(1);
   Object.defineProperty(args, "0", {value: 10, configurable: false});
-  %HeapObjectVerify(args);
   assertFalse(Object.getOwnPropertyDescriptor(args, "0").configurable);
-  %HeapObjectVerify(args);
   for (var i = 0; i < 10; i++) {
     args[i] = 1;
   }
-  %HeapObjectVerify(args);
   assertFalse(Object.getOwnPropertyDescriptor(args, "0").configurable);
-  %HeapObjectVerify(args);
 })();
 
 // Ensure read-only properties on the prototype chain cause TypeError.
@@ -33,11 +27,7 @@ function f(a, b, c, d) { return arguments; }
   for (var i = 0; i < index; i++) {
     store(o, i, 0);
   }
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   Object.defineProperty(proto, index, {value: 100, writable: false});
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   assertThrows(function() { store(o, index, 0); });
   assertEquals(100, o[index]);
 })();
@@ -52,11 +42,7 @@ function f(a, b, c, d) { return arguments; }
   for (var i = 0; i < index; i++) {
     store(o, i, 0);
   }
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   Object.defineProperty(proto, index, {value: 100, writable: false});
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   assertThrows(function() { store(o, index, 0); });
   assertEquals(100, o[index]);
 })();
@@ -71,11 +57,7 @@ function f(a, b, c, d) { return arguments; }
   for (var i = 0; i < index; i++) {
     store(o, i, 0);
   }
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   Object.defineProperty(proto, index, {value: 100, writable: false});
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   assertThrows(function() { store(o, index, 0); });
   assertEquals(100, o[index]);
 })();
@@ -90,11 +72,7 @@ function f(a, b, c, d) { return arguments; }
   for (var i = 0; i < index; i++) {
     store(o, i, 0);
   }
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   Object.defineProperty(proto, index, {value: 100, writable: false});
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   assertThrows(function() { store(o, index, 0); });
   assertEquals(100, o[index]);
 })();
@@ -109,17 +87,12 @@ function f(a, b, c, d) { return arguments; }
   for (var i = 0; i < index; i++) {
     store(o, i, 0);
   }
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   Object.preventExtensions(proto);
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   Object.defineProperty(proto, index, {value: 100, writable: false});
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   assertThrows(function() { store(o, index, 0); });
   assertEquals(100, o[index]);
 })();
+
 // Extensions prevented arguments object.
 (function () {
   var o = [];
@@ -130,14 +103,8 @@ function f(a, b, c, d) { return arguments; }
   for (var i = 0; i < index; i++) {
     store(o, i, 0);
   }
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   Object.preventExtensions(proto);
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   Object.defineProperty(proto, index, {value: 100, writable: false});
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   assertThrows(function() { store(o, index, 0); });
   assertEquals(100, o[index]);
 })();
@@ -153,11 +120,7 @@ function f(a, b, c, d) { return arguments; }
     store(o, i, 0);
   }
   proto[1 << 30] = 1;
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   Object.defineProperty(proto, index, {value: 100, writable: false});
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   assertThrows(function() { store(o, index, 0); });
   assertEquals(100, o[index]);
 })();
@@ -171,11 +134,7 @@ function f(a, b, c, d) { return arguments; }
   for (var i = 0; i < 3; i++) {
     store(o, i, 0);
   }
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   Object.freeze(proto);
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   assertThrows(function() { store(o, 3, 0); });
   assertEquals(3, o[3]);
 })();
@@ -189,11 +148,7 @@ function f(a, b, c, d) { return arguments; }
   for (var i = 0; i < 3; i++) {
     store(o, i, 0);
   }
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   Object.freeze(proto);
-  %HeapObjectVerify(proto);
-  %HeapObjectVerify(o);
   assertThrows(function() { store(o, 3, 0); });
   assertEquals(3, o[3]);
 })();