VM: Simplify irregexp entry stub.

runtime/vm/intrinsifier_arm64.cc

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_ARM64.
 #if defined(TARGET_ARCH_ARM64)
 
 #include "vm/intrinsifier.h"
 
 #include "vm/assembler.h"
@@ skipping 2079 matching lines @@
   // string CIDs as well as stored function pointers are in sequence.
   __ ldr(R2, Address(SP, kRegExpParamOffset));
   __ ldr(R1, Address(SP, kStringParamOffset));
   __ LoadClassId(R1, R1);
   __ AddImmediate(R1, R1, -kOneByteStringCid);
   __ add(R1, R2, Operand(R1, LSL, kWordSizeLog2));
   __ ldr(R0, FieldAddress(R1, JSRegExp::function_offset(kOneByteStringCid)));
 
   // Registers are now set up for the lazy compile stub. It expects the function
   // in R0, the argument descriptor in R4, and IC-Data in R5.
-  static const intptr_t arg_count = RegExpMacroAssembler::kParamCount;
-  __ LoadObject(R4, Array::Handle(ArgumentsDescriptor::New(arg_count)));
   __ eor(R5, R5, Operand(R5));
 
   // Tail-call the function.
   __ ldr(R1, FieldAddress(R0, Function::entry_point_offset()));
   __ br(R1);
 }
 
 
 // On stack: user tag (+0).
 void Intrinsifier::UserTag_makeCurrent(Assembler* assembler) {
@@ skipping 22 matching lines @@
 
 void Intrinsifier::Profiler_getCurrentTag(Assembler* assembler) {
   __ LoadIsolate(R0);
   __ ldr(R0, Address(R0, Isolate::current_tag_offset()));
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM64