_ Git - BearSSL/blob - T0/WordData.cs

   1 /*
   2  * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining
   5  * a copy of this software and associated documentation files (the
   6  * "Software"), to deal in the Software without restriction, including
   7  * without limitation the rights to use, copy, modify, merge, publish,
   8  * distribute, sublicense, and/or sell copies of the Software, and to
   9  * permit persons to whom the Software is furnished to do so, subject to
  10  * the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be
  13  * included in all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  19  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  20  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22  * SOFTWARE.
  23  */
  24
  25 using System;
  26 using System.Collections.Generic;
  27
  28 class WordData : Word {
  29
  30         ConstData blob;
  31         string baseBlobName;
  32         int offset;
  33         bool ongoingResolution;
  34
  35         internal WordData(T0Comp owner, string name,
  36                 ConstData blob, int offset)
  37                 : base(owner, name)
  38         {
  39                 this.blob = blob;
  40                 this.offset = offset;
  41                 StackEffect = new SType(0, 1);
  42         }
  43
  44         internal WordData(T0Comp owner, string name,
  45                 string baseBlobName, int offset)
  46                 : base(owner, name)
  47         {
  48                 this.baseBlobName = baseBlobName;
  49                 this.offset = offset;
  50                 StackEffect = new SType(0, 1);
  51         }
  52
  53         internal override void Resolve()
  54         {
  55                 if (blob != null) {
  56                         return;
  57                 }
  58                 if (ongoingResolution) {
  59                         throw new Exception(String.Format(
  60                                 "circular reference in blobs ({0})", Name));
  61                 }
  62                 ongoingResolution = true;
  63                 WordData wd = TC.Lookup(baseBlobName) as WordData;
  64                 if (wd == null) {
  65                         throw new Exception(String.Format(
  66                                 "data word '{0}' based on non-data word '{1}'",
  67                                 Name, baseBlobName));
  68                 }
  69                 wd.Resolve();
  70                 blob = wd.blob;
  71                 offset += wd.offset;
  72                 ongoingResolution = false;
  73         }
  74
  75         internal override void Run(CPU cpu)
  76         {
  77                 Resolve();
  78                 cpu.Push(new TValue(offset, new TPointerBlob(blob)));
  79         }
  80
  81         internal override List<ConstData> GetDataBlocks()
  82         {
  83                 Resolve();
  84                 List<ConstData> r = new List<ConstData>();
  85                 r.Add(blob);
  86                 return r;
  87         }
  88
  89         internal override void GenerateCodeElements(List<CodeElement> dst)
  90         {
  91                 Resolve();
  92                 dst.Add(new CodeElementUInt(0));
  93                 dst.Add(new CodeElementUIntInt(1, blob.Address + offset));
  94                 dst.Add(new CodeElementUInt(0));
  95         }
  96 }