DBC: Implement OneByteStringFromCharCode and StringToCharCode.

runtime/vm/constants_dbc.h

 // Copyright (c) 2016, 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.
 
 #ifndef VM_CONSTANTS_DBC_H_
 #define VM_CONSTANTS_DBC_H_
 
 #include "platform/globals.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 138 matching lines @@
 //
 //  - InstanceCall<N> ArgC, D; InstanceCall<N>Opt ArgC, D
 //
 //    Lookup and invoke method with N checked arguments using ICData in PP[D]
 //    with arguments SP[-(1+ArgC)], ..., SP[-1].
 //
 //  - NativeCall, NativeBootstrapCall
 //
 //    Invoke native function SP[-1] with argc_tag SP[0].
 //
+//  - OneByteStringFromCharCode rA, rX
+//
+//    Load the one-character symbol with the char code given by the Smi
+//    in FP[rX] into FP[rA].
+//
+//  - StringToCharCode rA, rX
+//
+//    Load and smi-encode the single char code of the string in FP[rX] into
+//    FP[rA]. If the string's length is not 1, load smi -1 instead.
+//
 //  - AddTOS; SubTOS; MulTOS; BitOrTOS; BitAndTOS; EqualTOS; LessThanTOS;
 //    GreaterThanTOS;
 //
 //    Smi fast-path for a corresponding method. Checks if SP[0] and SP[-1] are
 //    both smis and result of SP[0] <op> SP[-1] is a smi - if this is true
 //    then pops operands and pushes result on the stack and skips the next
 //    instruction (which implements a slow path fallback).
 //
 //  - Add, Sub, Mul, Div, Mod, Shl, Shr rA, rB, rC
 //
@@ skipping 276 matching lines @@
   V(PushConstant,                    D, lit, ___, ___) \
   V(StoreLocal,                      X, xeg, ___, ___) \
   V(PopLocal,                        X, xeg, ___, ___) \
   V(StaticCall,                    A_D, num, num, ___) \
   V(InstanceCall1,                 A_D, num, num, ___) \
   V(InstanceCall2,                 A_D, num, num, ___) \
   V(InstanceCall1Opt,              A_D, num, num, ___) \
   V(InstanceCall2Opt,              A_D, num, num, ___) \
   V(NativeCall,                      0, ___, ___, ___) \
   V(NativeBootstrapCall,             0, ___, ___, ___) \
+  V(OneByteStringFromCharCode,     A_X, reg, xeg, ___) \
+  V(StringToCharCode,              A_X, reg, xeg, ___) \
   V(AddTOS,                          0, ___, ___, ___) \
   V(SubTOS,                          0, ___, ___, ___) \
   V(MulTOS,                          0, ___, ___, ___) \
   V(BitOrTOS,                        0, ___, ___, ___) \
   V(BitAndTOS,                       0, ___, ___, ___) \
   V(EqualTOS,                        0, ___, ___, ___) \
   V(LessThanTOS,                     0, ___, ___, ___) \
   V(GreaterThanTOS,                  0, ___, ___, ___) \
   V(Add,                         A_B_C, reg, reg, reg) \
   V(Sub,                         A_B_C, reg, reg, reg) \
@@ skipping 160 matching lines @@
   kNumberOfDummyFpuRegisters,
 };
 const FpuRegister FpuTMP = kFakeFpuRegister;
 const intptr_t kNumberOfFpuRegisters = 1;
 
 enum Condition { EQ, NE };
 
 }  // namespace dart
 
 #endif  // VM_CONSTANTS_DBC_H_