[builtins] Remove STRING_ADD_LEFT and STRING_ADD_RIGHT builtins.

src/full-codegen/mips/full-codegen-mips.cc

Index: src/full-codegen/mips/full-codegen-mips.cc
diff --git a/src/full-codegen/mips/full-codegen-mips.cc b/src/full-codegen/mips/full-codegen-mips.cc
index 2e3cb94f71a359bd38cb081211b3f34d6367c7da..1bf21f085b2adfd9c50317ac4ef374437af15550 100644
--- a/src/full-codegen/mips/full-codegen-mips.cc
+++ b/src/full-codegen/mips/full-codegen-mips.cc
@@ -3318,94 +3318,6 @@ void FullCodeGenerator::EmitIsSimdValue(CallRuntime* expr) {
 }
 
 
-void FullCodeGenerator::EmitIsStringWrapperSafeForDefaultValueOf(
-    CallRuntime* expr) {
-  ZoneList<Expression*>* args = expr->arguments();
-  DCHECK(args->length() == 1);
-
-  VisitForAccumulatorValue(args->at(0));
-
-  Label materialize_true, materialize_false, skip_lookup;
-  Label* if_true = NULL;
-  Label* if_false = NULL;
-  Label* fall_through = NULL;
-  context()->PrepareTest(&materialize_true, &materialize_false,
-                         &if_true, &if_false, &fall_through);
-
-  __ AssertNotSmi(v0);
-
-  __ lw(a1, FieldMemOperand(v0, HeapObject::kMapOffset));
-  __ lbu(t0, FieldMemOperand(a1, Map::kBitField2Offset));
-  __ And(t0, t0, 1 << Map::kStringWrapperSafeForDefaultValueOf);
-  __ Branch(&skip_lookup, ne, t0, Operand(zero_reg));
-
-  // Check for fast case object. Generate false result for slow case object.
-  __ lw(a2, FieldMemOperand(v0, JSObject::kPropertiesOffset));
-  __ lw(a2, FieldMemOperand(a2, HeapObject::kMapOffset));
-  __ LoadRoot(t0, Heap::kHashTableMapRootIndex);
-  __ Branch(if_false, eq, a2, Operand(t0));
-
-  // Look for valueOf name in the descriptor array, and indicate false if
-  // found. Since we omit an enumeration index check, if it is added via a
-  // transition that shares its descriptor array, this is a false positive.
-  Label entry, loop, done;
-
-  // Skip loop if no descriptors are valid.
-  __ NumberOfOwnDescriptors(a3, a1);
-  __ Branch(&done, eq, a3, Operand(zero_reg));
-
-  __ LoadInstanceDescriptors(a1, t0);
-  // t0: descriptor array.
-  // a3: valid entries in the descriptor array.
-  STATIC_ASSERT(kSmiTag == 0);
-  STATIC_ASSERT(kSmiTagSize == 1);
-  STATIC_ASSERT(kPointerSize == 4);
-  __ li(at, Operand(DescriptorArray::kDescriptorSize));
-  __ Mul(a3, a3, at);
-  // Calculate location of the first key name.
-  __ Addu(t0, t0, Operand(DescriptorArray::kFirstOffset - kHeapObjectTag));
-  // Calculate the end of the descriptor array.
-  __ mov(a2, t0);
-  __ sll(t1, a3, kPointerSizeLog2);
-  __ Addu(a2, a2, t1);
-
-  // Loop through all the keys in the descriptor array. If one of these is the
-  // string "valueOf" the result is false.
-  // The use of t2 to store the valueOf string assumes that it is not otherwise
-  // used in the loop below.
-  __ LoadRoot(t2, Heap::kvalueOf_stringRootIndex);
-  __ jmp(&entry);
-  __ bind(&loop);
-  __ lw(a3, MemOperand(t0, 0));
-  __ Branch(if_false, eq, a3, Operand(t2));
-  __ Addu(t0, t0, Operand(DescriptorArray::kDescriptorSize * kPointerSize));
-  __ bind(&entry);
-  __ Branch(&loop, ne, t0, Operand(a2));
-
-  __ bind(&done);
-
-  // Set the bit in the map to indicate that there is no local valueOf field.
-  __ lbu(a2, FieldMemOperand(a1, Map::kBitField2Offset));
-  __ Or(a2, a2, Operand(1 << Map::kStringWrapperSafeForDefaultValueOf));
-  __ sb(a2, FieldMemOperand(a1, Map::kBitField2Offset));
-
-  __ bind(&skip_lookup);
-
-  // If a valueOf property is not found on the object check that its
-  // prototype is the un-modified String prototype. If not result is false.
-  __ lw(a2, FieldMemOperand(a1, Map::kPrototypeOffset));
-  __ JumpIfSmi(a2, if_false);
-  __ lw(a2, FieldMemOperand(a2, HeapObject::kMapOffset));
-  __ lw(a3, ContextOperand(cp, Context::GLOBAL_OBJECT_INDEX));
-  __ lw(a3, FieldMemOperand(a3, GlobalObject::kNativeContextOffset));
-  __ lw(a3, ContextOperand(a3, Context::STRING_FUNCTION_PROTOTYPE_MAP_INDEX));
-  PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
-  Split(eq, a2, Operand(a3), if_true, if_false, fall_through);
-
-  context()->Plug(if_true, if_false);
-}
-
-
 void FullCodeGenerator::EmitIsFunction(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 1);