Active smi-only optimizations for large array literals.

src/arm/ic-arm.cc

 // Copyright 2011 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 1362 matching lines @@
   // Smi stores don't require further checks.
   Label non_smi_value;
   __ JumpIfNotSmi(value, &non_smi_value);
   // It's irrelevant whether array is smi-only or not when writing a smi.
   __ add(address, elements, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
   __ add(address, address, Operand(key, LSL, kPointerSizeLog2 - kSmiTagSize));
   __ str(value, MemOperand(address));
   __ Ret();
 
   __ bind(&non_smi_value);
-  if (FLAG_smi_only_arrays) {
-    // Escape to slow case when writing non-smi into smi-only array.
-    __ CheckFastObjectElements(receiver_map, scratch_value, &slow);
-  }
+  // Escape to slow case when writing non-smi into smi-only array.
+  __ CheckFastObjectElements(receiver_map, scratch_value, &slow);
   // Fast elements array, store the value to the elements backing store.
   __ add(address, elements, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
   __ add(address, address, Operand(key, LSL, kPointerSizeLog2 - kSmiTagSize));
   __ str(value, MemOperand(address));
   // Update write barrier for the elements array address.
   __ mov(scratch_value, value);  // Preserve the value which is returned.
   __ RecordWrite(elements,
                  address,
                  scratch_value,
                  kLRHasNotBeenSaved,
@@ skipping 271 matching lines @@
     Register reg = Assembler::GetRn(instr_at_patch);
     patcher.masm()->tst(reg, Operand(kSmiTagMask));
     patcher.EmitCondition(eq);
   }
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM