xref: /freebsd/contrib/bearssl/T0/OpcodeJump.cs (revision 2aaf9152a852aba9eb2036b95f4948ee77988826)
1*0957b409SSimon J. Gerraty /*
2*0957b409SSimon J. Gerraty  * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
3*0957b409SSimon J. Gerraty  *
4*0957b409SSimon J. Gerraty  * Permission is hereby granted, free of charge, to any person obtaining
5*0957b409SSimon J. Gerraty  * a copy of this software and associated documentation files (the
6*0957b409SSimon J. Gerraty  * "Software"), to deal in the Software without restriction, including
7*0957b409SSimon J. Gerraty  * without limitation the rights to use, copy, modify, merge, publish,
8*0957b409SSimon J. Gerraty  * distribute, sublicense, and/or sell copies of the Software, and to
9*0957b409SSimon J. Gerraty  * permit persons to whom the Software is furnished to do so, subject to
10*0957b409SSimon J. Gerraty  * the following conditions:
11*0957b409SSimon J. Gerraty  *
12*0957b409SSimon J. Gerraty  * The above copyright notice and this permission notice shall be
13*0957b409SSimon J. Gerraty  * included in all copies or substantial portions of the Software.
14*0957b409SSimon J. Gerraty  *
15*0957b409SSimon J. Gerraty  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16*0957b409SSimon J. Gerraty  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17*0957b409SSimon J. Gerraty  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18*0957b409SSimon J. Gerraty  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19*0957b409SSimon J. Gerraty  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20*0957b409SSimon J. Gerraty  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21*0957b409SSimon J. Gerraty  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22*0957b409SSimon J. Gerraty  * SOFTWARE.
23*0957b409SSimon J. Gerraty  */
24*0957b409SSimon J. Gerraty 
25*0957b409SSimon J. Gerraty using System;
26*0957b409SSimon J. Gerraty using System.Collections.Generic;
27*0957b409SSimon J. Gerraty 
28*0957b409SSimon J. Gerraty abstract class OpcodeJump : Opcode {
29*0957b409SSimon J. Gerraty 
30*0957b409SSimon J. Gerraty 	int disp;
31*0957b409SSimon J. Gerraty 
OpcodeJump()32*0957b409SSimon J. Gerraty 	internal OpcodeJump() : this(Int32.MinValue)
33*0957b409SSimon J. Gerraty 	{
34*0957b409SSimon J. Gerraty 	}
35*0957b409SSimon J. Gerraty 
OpcodeJump(int disp)36*0957b409SSimon J. Gerraty 	internal OpcodeJump(int disp)
37*0957b409SSimon J. Gerraty 	{
38*0957b409SSimon J. Gerraty 		this.disp = disp;
39*0957b409SSimon J. Gerraty 	}
40*0957b409SSimon J. Gerraty 
41*0957b409SSimon J. Gerraty 	internal override int JumpDisp {
42*0957b409SSimon J. Gerraty 		get {
43*0957b409SSimon J. Gerraty 			return disp;
44*0957b409SSimon J. Gerraty 		}
45*0957b409SSimon J. Gerraty 	}
46*0957b409SSimon J. Gerraty 
Run(CPU cpu)47*0957b409SSimon J. Gerraty 	internal override void Run(CPU cpu)
48*0957b409SSimon J. Gerraty 	{
49*0957b409SSimon J. Gerraty 		cpu.ipOff += disp;
50*0957b409SSimon J. Gerraty 	}
51*0957b409SSimon J. Gerraty 
ResolveJump(int disp)52*0957b409SSimon J. Gerraty 	internal override void ResolveJump(int disp)
53*0957b409SSimon J. Gerraty 	{
54*0957b409SSimon J. Gerraty 		if (this.disp != Int32.MinValue) {
55*0957b409SSimon J. Gerraty 			throw new Exception("Jump already resolved");
56*0957b409SSimon J. Gerraty 		}
57*0957b409SSimon J. Gerraty 		this.disp = disp;
58*0957b409SSimon J. Gerraty 	}
59*0957b409SSimon J. Gerraty 
FixUp(CodeElement[] gcode, int off)60*0957b409SSimon J. Gerraty 	internal override void FixUp(CodeElement[] gcode, int off)
61*0957b409SSimon J. Gerraty 	{
62*0957b409SSimon J. Gerraty 		gcode[off].SetJumpTarget(gcode[off + 1 + disp]);
63*0957b409SSimon J. Gerraty 	}
64*0957b409SSimon J. Gerraty }
65