Introduce code flushing of RegExp code.

src/arm/code-stubs-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 4403 matching lines @@
   STATIC_ASSERT(4 == kAsciiStringTag);
   STATIC_ASSERT(kTwoByteStringTag == 0);
   // Find the code object based on the assumptions above.
   __ and_(r0, r0, Operand(kStringEncodingMask));
   __ mov(r3, Operand(r0, ASR, 2), SetCC);
   __ ldr(r7, FieldMemOperand(regexp_data, JSRegExp::kDataAsciiCodeOffset), ne);
   __ ldr(r7, FieldMemOperand(regexp_data, JSRegExp::kDataUC16CodeOffset), eq);
 
   // Check that the irregexp code has been generated for the actual string
   // encoding. If it has, the field contains a code object otherwise it contains
-  // the hole.
-  __ CompareObjectType(r7, r0, r0, CODE_TYPE);
-  __ b(ne, &runtime);
+  // a smi (code flushing support).
+  __ JumpIfSmi(r7, &runtime);
 
   // r3: encoding of subject string (1 if ASCII, 0 if two_byte);
   // r7: code
   // subject: Subject string
   // regexp_data: RegExp data (FixedArray)
   // Load used arguments before starting to push arguments for call to native
   // RegExp code to avoid handling changing stack height.
   __ ldr(r1, MemOperand(sp, kPreviousIndexOffset));
   __ mov(r1, Operand(r1, ASR, kSmiTagSize));
 
@@ skipping 2165 matching lines @@
   __ mov(result, Operand(0));
   __ Ret();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM