[fullcodegen] Remove the hacky %_FastOneByteArrayJoin intrinsic.

src/full-codegen/x87/full-codegen-x87.cc

Index: src/full-codegen/x87/full-codegen-x87.cc
diff --git a/src/full-codegen/x87/full-codegen-x87.cc b/src/full-codegen/x87/full-codegen-x87.cc
index 74d307eec4e14d56303a321ec2618e36032d04a2..9d68852a8306270a8719236b2ded6ba81c95e21e 100644
--- a/src/full-codegen/x87/full-codegen-x87.cc
+++ b/src/full-codegen/x87/full-codegen-x87.cc
@@ -3318,275 +3318,6 @@ void FullCodeGenerator::EmitGetSuperConstructor(CallRuntime* expr) {
 }
 
 
-void FullCodeGenerator::EmitFastOneByteArrayJoin(CallRuntime* expr) {
-  Label bailout, done, one_char_separator, long_separator,
-      non_trivial_array, not_size_one_array, loop,
-      loop_1, loop_1_condition, loop_2, loop_2_entry, loop_3, loop_3_entry;
-
-  ZoneList<Expression*>* args = expr->arguments();
-  DCHECK(args->length() == 2);
-  // We will leave the separator on the stack until the end of the function.
-  VisitForStackValue(args->at(1));
-  // Load this to eax (= array)
-  VisitForAccumulatorValue(args->at(0));
-  // All aliases of the same register have disjoint lifetimes.
-  Register array = eax;
-  Register elements = no_reg;  // Will be eax.
-
-  Register index = edx;
-
-  Register string_length = ecx;
-
-  Register string = esi;
-
-  Register scratch = ebx;
-
-  Register array_length = edi;
-  Register result_pos = no_reg;  // Will be edi.
-
-  // Separator operand is already pushed.
-  Operand separator_operand = Operand(esp, 2 * kPointerSize);
-  Operand result_operand = Operand(esp, 1 * kPointerSize);
-  Operand array_length_operand = Operand(esp, 0);
-  __ sub(esp, Immediate(2 * kPointerSize));
-  __ cld();
-  // Check that the array is a JSArray
-  __ JumpIfSmi(array, &bailout);
-  __ CmpObjectType(array, JS_ARRAY_TYPE, scratch);
-  __ j(not_equal, &bailout);
-
-  // Check that the array has fast elements.
-  __ CheckFastElements(scratch, &bailout);
-
-  // If the array has length zero, return the empty string.
-  __ mov(array_length, FieldOperand(array, JSArray::kLengthOffset));
-  __ SmiUntag(array_length);
-  __ j(not_zero, &non_trivial_array);
-  __ mov(result_operand, isolate()->factory()->empty_string());
-  __ jmp(&done);
-
-  // Save the array length.
-  __ bind(&non_trivial_array);
-  __ mov(array_length_operand, array_length);
-
-  // Save the FixedArray containing array's elements.
-  // End of array's live range.
-  elements = array;
-  __ mov(elements, FieldOperand(array, JSArray::kElementsOffset));
-  array = no_reg;
-
-
-  // Check that all array elements are sequential one-byte strings, and
-  // accumulate the sum of their lengths, as a smi-encoded value.
-  __ Move(index, Immediate(0));
-  __ Move(string_length, Immediate(0));
-  // Loop condition: while (index < length).
-  // Live loop registers: index, array_length, string,
-  //                      scratch, string_length, elements.
-  if (generate_debug_code_) {
-    __ cmp(index, array_length);
-    __ Assert(less, kNoEmptyArraysHereInEmitFastOneByteArrayJoin);
-  }
-  __ bind(&loop);
-  __ mov(string, FieldOperand(elements,
-                              index,
-                              times_pointer_size,
-                              FixedArray::kHeaderSize));
-  __ JumpIfSmi(string, &bailout);
-  __ mov(scratch, FieldOperand(string, HeapObject::kMapOffset));
-  __ movzx_b(scratch, FieldOperand(scratch, Map::kInstanceTypeOffset));
-  __ and_(scratch, Immediate(
-      kIsNotStringMask | kStringEncodingMask | kStringRepresentationMask));
-  __ cmp(scratch, kStringTag | kOneByteStringTag | kSeqStringTag);
-  __ j(not_equal, &bailout);
-  __ add(string_length,
-         FieldOperand(string, SeqOneByteString::kLengthOffset));
-  __ j(overflow, &bailout);
-  __ add(index, Immediate(1));
-  __ cmp(index, array_length);
-  __ j(less, &loop);
-
-  // If array_length is 1, return elements[0], a string.
-  __ cmp(array_length, 1);
-  __ j(not_equal, &not_size_one_array);
-  __ mov(scratch, FieldOperand(elements, FixedArray::kHeaderSize));
-  __ mov(result_operand, scratch);
-  __ jmp(&done);
-
-  __ bind(&not_size_one_array);
-
-  // End of array_length live range.
-  result_pos = array_length;
-  array_length = no_reg;
-
-  // Live registers:
-  // string_length: Sum of string lengths, as a smi.
-  // elements: FixedArray of strings.
-
-  // Check that the separator is a flat one-byte string.
-  __ mov(string, separator_operand);
-  __ JumpIfSmi(string, &bailout);
-  __ mov(scratch, FieldOperand(string, HeapObject::kMapOffset));
-  __ movzx_b(scratch, FieldOperand(scratch, Map::kInstanceTypeOffset));
-  __ and_(scratch, Immediate(
-      kIsNotStringMask | kStringEncodingMask | kStringRepresentationMask));
-  __ cmp(scratch, kStringTag | kOneByteStringTag | kSeqStringTag);
-  __ j(not_equal, &bailout);
-
-  // Add (separator length times array_length) - separator length
-  // to string_length.
-  __ mov(scratch, separator_operand);
-  __ mov(scratch, FieldOperand(scratch, SeqOneByteString::kLengthOffset));
-  __ sub(string_length, scratch);  // May be negative, temporarily.
-  __ imul(scratch, array_length_operand);
-  __ j(overflow, &bailout);
-  __ add(string_length, scratch);
-  __ j(overflow, &bailout);
-
-  __ shr(string_length, 1);
-
-  // Bailout for large object allocations.
-  __ cmp(string_length, Page::kMaxRegularHeapObjectSize);
-  __ j(greater, &bailout);
-
-  // Live registers and stack values:
-  //   string_length
-  //   elements
-  __ AllocateOneByteString(result_pos, string_length, scratch, index, string,
-                           &bailout);
-  __ mov(result_operand, result_pos);
-  __ lea(result_pos, FieldOperand(result_pos, SeqOneByteString::kHeaderSize));
-
-
-  __ mov(string, separator_operand);
-  __ cmp(FieldOperand(string, SeqOneByteString::kLengthOffset),
-         Immediate(Smi::FromInt(1)));
-  __ j(equal, &one_char_separator);
-  __ j(greater, &long_separator);
-
-
-  // Empty separator case
-  __ mov(index, Immediate(0));
-  __ jmp(&loop_1_condition);
-  // Loop condition: while (index < length).
-  __ bind(&loop_1);
-  // Each iteration of the loop concatenates one string to the result.
-  // Live values in registers:
-  //   index: which element of the elements array we are adding to the result.
-  //   result_pos: the position to which we are currently copying characters.
-  //   elements: the FixedArray of strings we are joining.
-
-  // Get string = array[index].
-  __ mov(string, FieldOperand(elements, index,
-                              times_pointer_size,
-                              FixedArray::kHeaderSize));
-  __ mov(string_length,
-         FieldOperand(string, String::kLengthOffset));
-  __ shr(string_length, 1);
-  __ lea(string,
-         FieldOperand(string, SeqOneByteString::kHeaderSize));
-  __ CopyBytes(string, result_pos, string_length, scratch);
-  __ add(index, Immediate(1));
-  __ bind(&loop_1_condition);
-  __ cmp(index, array_length_operand);
-  __ j(less, &loop_1);  // End while (index < length).
-  __ jmp(&done);
-
-
-
-  // One-character separator case
-  __ bind(&one_char_separator);
-  // Replace separator with its one-byte character value.
-  __ mov_b(scratch, FieldOperand(string, SeqOneByteString::kHeaderSize));
-  __ mov_b(separator_operand, scratch);
-
-  __ Move(index, Immediate(0));
-  // Jump into the loop after the code that copies the separator, so the first
-  // element is not preceded by a separator
-  __ jmp(&loop_2_entry);
-  // Loop condition: while (index < length).
-  __ bind(&loop_2);
-  // Each iteration of the loop concatenates one string to the result.
-  // Live values in registers:
-  //   index: which element of the elements array we are adding to the result.
-  //   result_pos: the position to which we are currently copying characters.
-
-  // Copy the separator character to the result.
-  __ mov_b(scratch, separator_operand);
-  __ mov_b(Operand(result_pos, 0), scratch);
-  __ inc(result_pos);
-
-  __ bind(&loop_2_entry);
-  // Get string = array[index].
-  __ mov(string, FieldOperand(elements, index,
-                              times_pointer_size,
-                              FixedArray::kHeaderSize));
-  __ mov(string_length,
-         FieldOperand(string, String::kLengthOffset));
-  __ shr(string_length, 1);
-  __ lea(string,
-         FieldOperand(string, SeqOneByteString::kHeaderSize));
-  __ CopyBytes(string, result_pos, string_length, scratch);
-  __ add(index, Immediate(1));
-
-  __ cmp(index, array_length_operand);
-  __ j(less, &loop_2);  // End while (index < length).
-  __ jmp(&done);
-
-
-  // Long separator case (separator is more than one character).
-  __ bind(&long_separator);
-
-  __ Move(index, Immediate(0));
-  // Jump into the loop after the code that copies the separator, so the first
-  // element is not preceded by a separator
-  __ jmp(&loop_3_entry);
-  // Loop condition: while (index < length).
-  __ bind(&loop_3);
-  // Each iteration of the loop concatenates one string to the result.
-  // Live values in registers:
-  //   index: which element of the elements array we are adding to the result.
-  //   result_pos: the position to which we are currently copying characters.
-
-  // Copy the separator to the result.
-  __ mov(string, separator_operand);
-  __ mov(string_length,
-         FieldOperand(string, String::kLengthOffset));
-  __ shr(string_length, 1);
-  __ lea(string,
-         FieldOperand(string, SeqOneByteString::kHeaderSize));
-  __ CopyBytes(string, result_pos, string_length, scratch);
-
-  __ bind(&loop_3_entry);
-  // Get string = array[index].
-  __ mov(string, FieldOperand(elements, index,
-                              times_pointer_size,
-                              FixedArray::kHeaderSize));
-  __ mov(string_length,
-         FieldOperand(string, String::kLengthOffset));
-  __ shr(string_length, 1);
-  __ lea(string,
-         FieldOperand(string, SeqOneByteString::kHeaderSize));
-  __ CopyBytes(string, result_pos, string_length, scratch);
-  __ add(index, Immediate(1));
-
-  __ cmp(index, array_length_operand);
-  __ j(less, &loop_3);  // End while (index < length).
-  __ jmp(&done);
-
-
-  __ bind(&bailout);
-  __ mov(result_operand, isolate()->factory()->undefined_value());
-  __ bind(&done);
-  __ mov(eax, result_operand);
-  // Drop temp values from the stack, and restore context register.
-  __ add(esp, Immediate(3 * kPointerSize));
-
-  __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
-  context()->Plug(eax);
-}
-
-
 void FullCodeGenerator::EmitDebugIsActive(CallRuntime* expr) {
   DCHECK(expr->arguments()->length() == 0);
   ExternalReference debug_is_active =