Adapt Danno's Track Allocation Info idea to fast literals. When allocating a literal array,

src/arm/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 161 matching lines @@
   //  -- r0    : value
   //  -- r1    : key
   //  -- r2    : receiver
   //  -- lr    : return address
   //  -- r3    : target map, scratch for subsequent call
   //  -- r4    : scratch (elements)
   // -----------------------------------
   Label loop, entry, convert_hole, gc_required, only_change_map, done;
   bool vfp2_supported = CpuFeatures::IsSupported(VFP2);
 
+  if (FLAG_use_allocation_site_info) {
+    masm->PerformAllocationSiteInfoCheck(fail);
+  }
+
   // Check for empty arrays, which only require a map transition and no changes
   // to the backing store.
   __ ldr(r4, FieldMemOperand(r2, JSObject::kElementsOffset));
   __ CompareRoot(r4, Heap::kEmptyFixedArrayRootIndex);
   __ b(eq, &only_change_map);
 
   __ push(lr);
   __ ldr(r5, FieldMemOperand(r4, FixedArray::kLengthOffset));
   // r4: source FixedArray
   // r5: number of elements (smi-tagged)
@@ skipping 116 matching lines @@
   // ----------- S t a t e -------------
   //  -- r0    : value
   //  -- r1    : key
   //  -- r2    : receiver
   //  -- lr    : return address
   //  -- r3    : target map, scratch for subsequent call
   //  -- r4    : scratch (elements)
   // -----------------------------------
   Label entry, loop, convert_hole, gc_required, only_change_map;
 
+  // TODO(mvstanton): don't pretransition double to object
+  // if (FLAG_use_allocation_site_info) {
+  //   masm->PerformAllocationSiteInfoCheck(fail);
+  // }
+
   // Check for empty arrays, which only require a map transition and no changes
   // to the backing store.
   __ ldr(r4, FieldMemOperand(r2, JSObject::kElementsOffset));
   __ CompareRoot(r4, Heap::kEmptyFixedArrayRootIndex);
   __ b(eq, &only_change_map);
 
   __ push(lr);
   __ Push(r3, r2, r1, r0);
   __ ldr(r5, FieldMemOperand(r4, FixedArray::kLengthOffset));
   // r4: source FixedDoubleArray
@@ skipping 353 matching lines @@
     patcher.masm()->add(r0, pc, Operand(-8));
     patcher.masm()->ldr(pc, MemOperand(pc, -4));
     patcher.masm()->dd(reinterpret_cast<uint32_t>(stub->instruction_start()));
   }
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM