Fraction class prototype and test (not to be committed).

runtime/vm/intrinsifier_ia32.cc

 // Copyright (c) 2013, 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 718 matching lines @@
   __ LoadObject(EAX, Bool::True());
   __ ret();
 
   // At least one of the arguments was not Smi.
   Label receiver_not_smi;
   __ Bind(&check_for_mint);
   __ movl(EAX, Address(ESP, + 2 * kWordSize));  // Receiver.
   __ testl(EAX, Immediate(kSmiTagMask));
   __ j(NOT_ZERO, &receiver_not_smi);
 
-  // Left (receiver) is Smi, return false if right is not Double.
+  // Left (receiver) is Smi, return false if right is not Double or Fraction.
   // Note that an instance of Mint or Bigint never contains a value that can be
   // represented by Smi.
   __ movl(EAX, Address(ESP, + 1 * kWordSize));  // Right argument.
-  __ CompareClassId(EAX, kDoubleCid, EDI);
+  __ LoadClassId(EDI, EAX);
+  __ cmpl(EDI, Immediate(kDoubleCid));
+  __ j(EQUAL, &fall_through);
+  __ cmpl(EDI, Immediate(kFractionCid));
   __ j(EQUAL, &fall_through);
   __ LoadObject(EAX, Bool::False());  // Smi == Mint -> false.
   __ ret();
 
   __ Bind(&receiver_not_smi);
   // EAX:: receiver.
   __ CompareClassId(EAX, kMintCid, EDI);
   __ j(NOT_EQUAL, &fall_through);
   // Receiver is Mint, return false if right is Smi.
   __ movl(EAX, Address(ESP, + 1 * kWordSize));  // Right argument.
@@ skipping 1400 matching lines @@
   __ Bind(&true_label);
   __ LoadObject(EAX, Bool::True());
   __ ret();
 }
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32