Intrinsify ExternalUint8Array.[].

runtime/vm/intrinsifier_ia32.cc

 // Copyright (c) 2012, 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 774 matching lines @@
   // EBX contains the SMI index which is shifted by 1.
   // This shift means we only multiply the index by 4 not 8 (sizeof float).
   // Store into array.
   __ movsd(FieldAddress(EAX, EBX, TIMES_4, Float64Array::data_offset()), XMM7);
   __ ret();
   __ Bind(&fall_through);
   return false;
 }
 
 
+bool Intrinsifier::ExternalUint8Array_getIndexed(Assembler* assembler) {
+  Label fall_through;
+  TestByteArrayIndex(assembler, &fall_through);
+  __ SmiUntag(EBX);
+  __ movl(EAX, FieldAddress(EAX, ExternalUint8Array::external_data_offset()));
+  __ movl(EAX, Address(EAX, ExternalByteArrayData<uint8_t>::data_offset()));
+  __ movzxb(EAX, Address(EAX, EBX, TIMES_1, 0));
+  __ SmiTag(EAX);
+  __ ret();
+  __ Bind(&fall_through);
+  return false;
+}
+
+
 // Tests if two top most arguments are smis, jumps to label not_smi if not.
 // Topmost argument is in EAX.
 static void TestBothArgumentsSmis(Assembler* assembler, Label* not_smi) {
   __ movl(EAX, Address(ESP, + 1 * kWordSize));
   __ movl(EBX, Address(ESP, + 2 * kWordSize));
   __ orl(EBX, EAX);
   __ testl(EBX, Immediate(kSmiTagMask));
   __ j(NOT_ZERO, not_smi, Assembler::kNearJump);
 }
 
@@ skipping 920 matching lines @@
   __ Bind(&is_true);
   __ LoadObject(EAX, bool_true);
   __ ret();
   return true;
 }
 
 #undef __
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32