Implement tracking and optimizations of packed arrays.

src/arm/lithium-codegen-arm.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2685 matching lines @@
     __ b(eq, &done);
     __ LoadRoot(ip, Heap::kFixedCOWArrayMapRootIndex);
     __ cmp(scratch, ip);
     __ b(eq, &done);
     // |scratch| still contains |input|'s map.
     __ ldr(scratch, FieldMemOperand(scratch, Map::kBitField2Offset));
     __ ubfx(scratch, scratch, Map::kElementsKindShift,
             Map::kElementsKindBitCount);
     __ cmp(scratch, Operand(FAST_ELEMENTS));
     __ b(eq, &done);
+    __ cmp(scratch, Operand(FAST_HOLEY_ELEMENTS));
+    __ b(eq, &done);
     __ cmp(scratch, Operand(FIRST_EXTERNAL_ARRAY_ELEMENTS_KIND));
     __ b(lt, &fail);
     __ cmp(scratch, Operand(LAST_EXTERNAL_ARRAY_ELEMENTS_KIND));
     __ b(le, &done);
     __ bind(&fail);
     __ Abort("Check for fast or external elements failed.");
     __ bind(&done);
   }
 }
 
@@ skipping 1954 matching lines @@
 }
 
 
 void LCodeGen::DoArrayLiteral(LArrayLiteral* instr) {
   Heap* heap = isolate()->heap();
   ElementsKind boilerplate_elements_kind =
       instr->hydrogen()->boilerplate_elements_kind();
 
   // Deopt if the array literal boilerplate ElementsKind is of a type different
   // than the expected one. The check isn't necessary if the boilerplate has
-  // already been converted to FAST_ELEMENTS.
-  if (boilerplate_elements_kind != FAST_ELEMENTS) {
+  // already been converted to TERMINAL_FAST_ELEMENTS_KIND.
+  if (boilerplate_elements_kind != TERMINAL_FAST_ELEMENTS_KIND) {
     __ LoadHeapObject(r1, instr->hydrogen()->boilerplate_object());
     // Load map into r2.
     __ ldr(r2, FieldMemOperand(r1, HeapObject::kMapOffset));
     // Load the map's "bit field 2".
     __ ldrb(r2, FieldMemOperand(r2, Map::kBitField2Offset));
     // Retrieve elements_kind from bit field 2.
     __ ubfx(r2, r2, Map::kElementsKindShift, Map::kElementsKindBitCount);
     __ cmp(r2, Operand(boilerplate_elements_kind));
     DeoptimizeIf(ne, instr->environment());
   }
@@ skipping 604 matching lines @@
   __ sub(scratch, result, Operand(index, LSL, kPointerSizeLog2 - kSmiTagSize));
   __ ldr(result, FieldMemOperand(scratch,
                                  FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal