Update to ES2015 == semantics for Symbol/SIMD wrappers

When == is invoked on a Symbol or SIMD vector and an object, the object should
be converted to a primitive with ToPrimitive and then compared again. This means,
for example, that for a Symbol or SIMD vector s, s == Object(s). This patch makes
that change in the implementation of ==. Only the runtime function needed to be
changed, as the code stubs and compiler specializations don't operate on Symbols
or SIMD vectors, and on these types, a fallback to the runtime function is always
used.

BUG=v8:3593
LOG=Y
R=adamk

Review URL: https://codereview.chromium.org/1421413002

Cr-Commit-Position: refs/heads/master@{#31614}

src/objects.cc

@@ -291,8 +291,9 @@ Maybe<bool> Object::Equals(Handle<Object> x, Handle<Object> y) {
       } else if (y->IsString()) {
         return Just(NumberEquals(x, String::ToNumber(Handle<String>::cast(y))));
       } else if (y->IsJSReceiver() && !y->IsUndetectableObject()) {
-        if (!JSReceiver::ToPrimitive(Handle<JSReceiver>::cast(y))
+        if (JSReceiver::ToPrimitive(Handle<JSReceiver>::cast(y)).ToHandle(&y)) {
-                 .ToHandle(&y)) {
+          continue;
+        } else {
           return Nothing<bool>();
         }
       } else {
@@ -309,8 +310,9 @@ Maybe<bool> Object::Equals(Handle<Object> x, Handle<Object> y) {
         x = String::ToNumber(Handle<String>::cast(x));
         return Just(NumberEquals(*x, Handle<Oddball>::cast(y)->to_number()));
       } else if (y->IsJSReceiver() && !y->IsUndetectableObject()) {
-        if (!JSReceiver::ToPrimitive(Handle<JSReceiver>::cast(y))
+        if (JSReceiver::ToPrimitive(Handle<JSReceiver>::cast(y)).ToHandle(&y)) {
-                 .ToHandle(&y)) {
+          continue;
+        } else {
           return Nothing<bool>();
         }
       } else {
@@ -330,25 +332,47 @@ Maybe<bool> Object::Equals(Handle<Object> x, Handle<Object> y) {
           return Nothing<bool>();
         }
         x = Oddball::ToNumber(Handle<Oddball>::cast(x));
+        continue;
       } else {
         return Just(false);
       }
     } else if (x->IsSymbol()) {
+      if (y->IsSymbol()) {
         return Just(x.is_identical_to(y));
+      } else if (y->IsJSReceiver() && !y->IsUndetectableObject()) {
+        if (JSReceiver::ToPrimitive(Handle<JSReceiver>::cast(y)).ToHandle(&y)) {
+          continue;
+        } else {
+          return Nothing<bool>();
+        }
+      } else {
+        return Just(false);
+      }
     } else if (x->IsSimd128Value()) {
-      if (!y->IsSimd128Value()) return Just(false);
+      if (y->IsSimd128Value()) {
         return Just(Simd128Value::Equals(Handle<Simd128Value>::cast(x),
                                          Handle<Simd128Value>::cast(y)));
+      } else if (y->IsJSReceiver() && !y->IsUndetectableObject()) {
+        if (JSReceiver::ToPrimitive(Handle<JSReceiver>::cast(y)).ToHandle(&y)) {
+          continue;
+        } else {
+          return Nothing<bool>();
+        }
+      } else {
+        return Just(false);
+      }
     } else if (x->IsJSReceiver() && !x->IsUndetectableObject()) {
       if (y->IsJSReceiver()) {
         return Just(x.is_identical_to(y));
-      } else if (y->IsNull() || y->IsSimd128Value() || y->IsSymbol() ||
+      } else if (y->IsNull() || y->IsUndefined()) {
-                 y->IsUndefined()) {
         return Just(false);
       } else if (y->IsBoolean()) {
         y = Oddball::ToNumber(Handle<Oddball>::cast(y));
-      }
+        continue;
-      if (!JSReceiver::ToPrimitive(Handle<JSReceiver>::cast(x)).ToHandle(&x)) {
+      } else if (JSReceiver::ToPrimitive(Handle<JSReceiver>::cast(x))
+                     .ToHandle(&x)) {
+        continue;
+      } else {
         return Nothing<bool>();
       }
     } else {
@@ -356,6 +380,7 @@ Maybe<bool> Object::Equals(Handle<Object> x, Handle<Object> y) {
           (x->IsNull() || x->IsUndefined() || x->IsUndetectableObject()) &&
           (y->IsNull() || y->IsUndefined() || y->IsUndetectableObject()));
     }
+    UNREACHABLE();
   }
 }
 

test/cctest/test-api.cc

@@ -2366,7 +2366,7 @@ THREADED_TEST(SymbolProperties) {
   CHECK(sym_obj->IsSymbolObject());
   CHECK(!sym2->IsSymbolObject());
   CHECK(!obj->IsSymbolObject());
-  CHECK(!sym_obj->Equals(sym2));
+  CHECK(sym_obj->Equals(sym2));
   CHECK(!sym_obj->StrictEquals(sym2));
   CHECK(v8::SymbolObject::Cast(*sym_obj)->Equals(sym_obj));
   CHECK(v8::SymbolObject::Cast(*sym_obj)->ValueOf()->Equals(sym2));

test/mjsunit/double-equals.js

@@ -25,6 +25,8 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+// Flags: --harmony-simd
+
 /**
  * This test uses assert{True,False}(... == ...) instead of
  * assertEquals(..., ...) to not rely on the details of the
@@ -234,3 +236,15 @@ function testBadConversion(value) {
 testBadConversion(0);
 testBadConversion("string");
 testBadConversion(true);
+
+var s = Symbol();
+testEqual(s, s);
+testEqual(Object(s), s);
+testEqual(new Wrapper(s), s);
+testNotEqual(Object(s), Object(s));
+
+var simd = SIMD.Float32x4(1, 2, 3, 4);
+testEqual(simd, simd);
+testEqual(Object(simd), simd);
+testEqual(new Wrapper(simd), simd);
+testNotEqual(Object(simd), Object(simd));

test/mjsunit/es6/symbols.js

@@ -167,8 +167,8 @@ function TestEquality() {
     assertTrue(symbols[i] == symbols[i])
     assertFalse(symbols[i] === Object(symbols[i]))
     assertFalse(Object(symbols[i]) === symbols[i])
-    assertFalse(symbols[i] == Object(symbols[i]))
+    assertTrue(symbols[i] == Object(symbols[i]))
-    assertFalse(Object(symbols[i]) == symbols[i])
+    assertTrue(Object(symbols[i]) == symbols[i])
     assertTrue(symbols[i] === symbols[i].valueOf())
     assertTrue(symbols[i].valueOf() === symbols[i])
     assertTrue(symbols[i] == symbols[i].valueOf())

test/mjsunit/harmony/private.js

@@ -132,8 +132,8 @@ function TestEquality() {
     assertTrue(symbols[i] == symbols[i])
     assertFalse(symbols[i] === Object(symbols[i]))
     assertFalse(Object(symbols[i]) === symbols[i])
-    assertFalse(symbols[i] == Object(symbols[i]))
+    assertTrue(symbols[i] == Object(symbols[i]))
-    assertFalse(Object(symbols[i]) == symbols[i])
+    assertTrue(Object(symbols[i]) == symbols[i])
     assertTrue(symbols[i] === symbols[i].valueOf())
     assertTrue(symbols[i].valueOf() === symbols[i])
     assertTrue(symbols[i] == symbols[i].valueOf())

test/mjsunit/harmony/simd.js

@@ -337,8 +337,8 @@ function TestEquality(type, lanes) {
   assertTrue(instance == instance)
   assertFalse(instance === Object(instance))
   assertFalse(Object(instance) === instance)
-  assertFalse(instance == Object(instance))
+  assertTrue(instance == Object(instance))
-  assertFalse(Object(instance) == instance)
+  assertTrue(Object(instance) == instance)
   assertTrue(instance === instance.valueOf())
   assertTrue(instance.valueOf() === instance)
   assertTrue(instance == instance.valueOf())

test/test262/test262.status

@@ -620,9 +620,6 @@
   'intl402/String/prototype/toLocaleUpperCase/special_casing_Lithuanian': [FAIL],
   'intl402/String/prototype/toLocaleUpperCase/special_casing_Turkish': [FAIL],
 
-  # https://code.google.com/p/v8/issues/detail?id=3788
-  'language/expressions/equals/coerce-symbol-to-prim-return-prim': [FAIL],
-
   ######################## NEEDS INVESTIGATION ###########################
 
   # These test failures are specific to the intl402 suite and need investigation