Run intrinsified version of ObjectArray[]= even in checked mode (inline value type check for null a…

runtime/vm/intrinsifier_ia32.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 // The intrinsic code below is executed before a method has built its frame.
 // The return address is on the stack and the arguments below it.
 // Registers EDX (arguments descriptor) and ECX (function) must be preserved.
 // Each intrinsification method returns true if the corresponding
 // Dart method was intrinsified.
 
@@ skipping 196 matching lines @@
   __ j(ABOVE_EQUAL, &fall_through, Assembler::kNearJump);
   // Note that EBX is Smi, i.e, times 2.
   ASSERT(kSmiTagShift == 1);
   __ movl(EAX, FieldAddress(EAX, EBX, TIMES_2, sizeof(RawArray)));
   __ ret();
   __ Bind(&fall_through);
   return false;
 }
 
 
+static intptr_t ComputeObjectArrayTypeArgumentsOffset() {
+  const String& class_name = String::Handle(String::NewSymbol("ObjectArray"));
+  const Class& cls = Class::Handle(
+      Library::Handle(Library::CoreImplLibrary()).LookupClass(class_name));
+  ASSERT(!cls.IsNull());
+  ASSERT(cls.HasTypeArguments());
+  ASSERT(cls.NumTypeParameters() == 1);

[regis, 2012/03/26 22:30:29]

You actually want to make sure that the full type arguments vector has length
one. Checking the number of type parameters is not relevant. Use this instead:
ASSERT(cls.NumTypeArguments() == 1);

[srdjan, 2012/03/26 22:43:51]

Done.

+  intptr_t field_offset = cls.type_arguments_instance_field_offset();
+  ASSERT(field_offset != Class::kNoTypeArguments);
+  return field_offset;
+}
+
+
 // Intrinsify only for Smi value and index. Non-smi values need a store buffer
 // update. Array length is always a Smi.
 static bool Array_setIndexed(Assembler* assembler) {
+  Label fall_through;
   if (FLAG_enable_type_checks) {
-    return false;
+    intptr_t type_args_field_offset = ComputeObjectArrayTypeArgumentsOffset();
+    ASSERT(type_args_field_offset >= 0);
+    // Inline simple tests (Smi, null), fallthrough if not positive.
+    const Immediate raw_null =
+        Immediate(reinterpret_cast<intptr_t>(Object::null()));
+    Label checked_ok;
+    __ movl(EAX, Address(ESP, + 1 * kWordSize));

[regis, 2012/03/26 22:30:29]

I guess you are accessing the last argument, i.e. the value to store? How about
a comment?

[srdjan, 2012/03/26 22:43:51]

Done.

+    __ cmpl(EAX, raw_null);
+    __ j(EQUAL, &checked_ok, Assembler::kNearJump);
+    __ testl(EAX, Immediate(kSmiTagMask));
+    __ j(NOT_ZERO, &fall_through, Assembler::kNearJump);  // Non-smi value.
+
+    // Check if generic type is OK.
+    __ movl(EBX, Address(ESP, + 3 * kWordSize));  // Array.
+    __ movl(EBX, FieldAddress(EBX, type_args_field_offset));
+    // EBX: Type arguments of array.
+    __ movl(EAX, FieldAddress(EBX, Object::class_offset()));
+    // Check if it's Dynamic, int, or num.
+    __ cmpl(EAX, raw_null);  // Dynamic?
+    __ j(EQUAL, &checked_ok, Assembler::kNearJump);
+    // For now handle only TypeArguments and bail out if InstantiatedTypeArgs.
+    __ CompareObject(EAX, Object::ZoneHandle(Object::type_arguments_class()));
+    __ j(NOT_EQUAL, &fall_through, Assembler::kNearJump);
+    // Get type at index 0.
+    __ movl(EAX, FieldAddress(EBX, TypeArguments::type_at_offset(0)));
+    __ CompareObject(EAX, Type::ZoneHandle(Type::DynamicType()));
+    __ j(EQUAL,  &checked_ok, Assembler::kNearJump);
+    __ CompareObject(EAX, Type::ZoneHandle(Type::IntInterface()));
+    __ j(EQUAL,  &checked_ok, Assembler::kNearJump);
+    __ CompareObject(EAX, Type::ZoneHandle(Type::NumberInterface()));
+    __ j(NOT_EQUAL, &fall_through, Assembler::kNearJump);
+    // TODO(srdjan): Check classes.

[regis, 2012/03/26 22:30:29]

What do you mean by "Check classes"?

[srdjan, 2012/03/26 22:43:51]

Removed.

+    __ Bind(&checked_ok);
   }
-  Label fall_through;
   __ movl(EBX, Address(ESP, + 2 * kWordSize));  // Index.
   __ testl(EBX, Immediate(kSmiTagMask));
   // Index not Smi.
   __ j(NOT_ZERO, &fall_through, Assembler::kNearJump);
   __ movl(EAX, Address(ESP, + 3 * kWordSize));  // Array.
   // Range check.
   __ cmpl(EBX, FieldAddress(EAX, Array::length_offset()));
   // Runtime throws exception.
   __ j(ABOVE_EQUAL, &fall_through, Assembler::kNearJump);
   // Note that EBX is Smi, i.e, times 2.
@@ skipping 1010 matching lines @@
   }                                                                            \
 
 INTRINSIC_LIST(FIND_INTRINSICS);
 #undef FIND_INTRINSICS
   return false;
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32