Preserve optimized code map during GCs weakly.

src/mips/code-stubs-mips.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 291 matching lines @@
 
   __ bind(&check_optimized);
 
   __ IncrementCounter(counters->fast_new_closure_try_optimized(), 1, t2, t3);
 
   // a2 holds native context, a1 points to fixed array of 3-element entries
   // (native context, optimized code, literals).
   // The optimized code map must never be empty, so check the first elements.
   Label install_optimized;
   // Speculatively move code object into t0.
-  __ lw(t0, FieldMemOperand(a1, FixedArray::kHeaderSize + kPointerSize));
-  __ lw(t1, FieldMemOperand(a1, FixedArray::kHeaderSize));
+  __ lw(t0, FieldMemOperand(a1, SharedFunctionInfo::kFirstCodeSlot));
+  __ lw(t1, FieldMemOperand(a1, SharedFunctionInfo::kFirstContextSlot));
   __ Branch(&install_optimized, eq, a2, Operand(t1));
 
   // Iterate through the rest of map backwards.  t0 holds an index as a Smi.
   Label loop;
   __ lw(t0, FieldMemOperand(a1, FixedArray::kLengthOffset));
   __ bind(&loop);
   // Do not double check first entry.
-
   __ Branch(&install_unoptimized, eq, t0,
-            Operand(Smi::FromInt(SharedFunctionInfo::kEntryLength)));
-  __ Subu(t0, t0, Operand(
-      Smi::FromInt(SharedFunctionInfo::kEntryLength)));  // Skip an entry.
+            Operand(Smi::FromInt(SharedFunctionInfo::kSecondEntryIndex)));
+  __ Subu(t0, t0, Operand(Smi::FromInt(SharedFunctionInfo::kEntryLength)));
   __ Addu(t1, a1, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
   __ sll(at, t0, kPointerSizeLog2 - kSmiTagSize);
   __ Addu(t1, t1, Operand(at));
   __ lw(t1, MemOperand(t1));
   __ Branch(&loop, ne, a2, Operand(t1));
   // Hit: fetch the optimized code.
   __ Addu(t1, a1, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
   __ sll(at, t0, kPointerSizeLog2 - kSmiTagSize);
   __ Addu(t1, t1, Operand(at));
   __ Addu(t1, t1, Operand(kPointerSize));
@@ skipping 7459 matching lines @@
      __ Jump(generic_construct_stub, RelocInfo::CODE_TARGET);
   }
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS