xref: /freebsd/contrib/bearssl/T0/WordData.cs (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
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 }
97