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comparison lwasm/insn_tfm.c @ 357:0cf4948d53b4

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Checkpoint - adding actual cpu instructions
author lost@starbug
date Wed, 31 Mar 2010 20:12:20 -0600
parents old-trunk/lwasm/old/insn_tfm.c@eb230fa7d28e
children
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356:7166254491ed 357:0cf4948d53b4
1 /*
2 insn_tfm.c
3 Copyright © 2009 William Astle
4
5 This file is part of LWASM.
6
7 LWASM is free software: you can redistribute it and/or modify it under the
8 terms of the GNU General Public License as published by the Free Software
9 Foundation, either version 3 of the License, or (at your option) any later
10 version.
11
12 This program is distributed in the hope that it will be useful, but WITHOUT
13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 more details.
16
17 You should have received a copy of the GNU General Public License along with
18 this program. If not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #include <config.h>
22 #include <ctype.h>
23 #include <string.h>
24
25 #include "lwasm.h"
26 #include "instab.h"
27
28 PARSEFUNC(insn_parse_tfm)
29 {
30 static const char *reglist = "DXYUS AB 00EF";
31 int r0, r1;
32 char *c;
33 int tfm = 0;
34
35 c = strchr(reglist, toupper(*(*p)++));
36 if (!c)
37 {
38 lwasm_register_error(as, l, "Unknown operation");
39 return;
40 }
41 r0 = c - reglist;
42 if (**p == '+')
43 {
44 (*p)++;
45 tfm = 1;
46 }
47 else if (**p == '-')
48 {
49 (*p)++;
50 tfm = 2;
51 }
52 if (*(*p)++ != ',')
53 {
54 lwasm_register_error(as, l, "Unknown operation");
55 return;
56 }
57 c = strchr(reglist, toupper(*(*p)++));
58 if (!c)
59 {
60 lwasm_register_error(as, l, "Unknown operation");
61 return;
62 }
63 r1 = c - reglist;
64
65 if (**p == '+')
66 {
67 (*p)++;
68 tfm |= 4;
69 }
70 else if (**p == '-')
71 {
72 (*p)++;
73 tfm |= 8;
74 }
75
76 if (**p && !isspace(**p))
77 {
78 lwasm_register_error(as, l, "Bad operand");
79 return;
80 }
81
82 // valid values of tfm here are:
83 // 1: r0+,r1 (2)
84 // 4: r0,r1+ (3)
85 // 5: r0+,r1+ (0)
86 // 10: r0-,r1- (1)
87 switch (tfm)
88 {
89 case 5: //r0+,r1+
90 l -> lint = instab[l -> insn].ops[0];
91 break;
92
93 case 10: //r0-,r1-
94 l -> lint = instab[l -> insn].ops[1];
95 break;
96
97 case 1: // r0+,r1
98 l -> lint = instab[l -> insn].ops[2];
99 break;
100
101 case 4: // r0,r1+
102 l -> lint = instab[l -> insn].ops[3];
103 break;
104
105 default:
106 lwasm_register_error(as, l, "Unknown operation");
107 return;
108 }
109 l -> pb = (r0 << 4) | r1;
110 l -> len = OPLEN(l -> lint);
111 }
112
113 EMITFUNC(insn_emit_tfm)
114 {
115 lwasm_emitop(l, l -> lint);
116 lwasm_emit(l, l -> pb);
117 }
118
119 PARSEFUNC(insn_parse_tfmrtor)
120 {
121 int r0, r1;
122 static const char *regs = "D X Y U S A B 0 0 E F ";
123
124 // register to register (r0,r1)
125 // registers are in order:
126 // D,X,Y,U,S,PC,W,V
127 // A,B,CC,DP,0,0,E,F
128 r0 = lwasm_lookupreg2(regs, p);
129 if (r0 < 0 || *(*p)++ != ',')
130 {
131 lwasm_register_error(as, l, "Bad operand");
132 r0 = r1 = 0;
133 }
134 else
135 {
136 r1 = lwasm_lookupreg2(regs, p);
137 if (r1 < 0)
138 {
139 lwasm_register_error(as, l, "Bad operand");
140 r0 = r1 = 0;
141 }
142 }
143 l -> len = instab[l -> insn].ops[0] + 1;
144 l -> pb = (r0 << 4) | r1;
145 }
146
147 EMITFUNC(insn_emit_tfmrtor)
148 {
149 lwasm_emitop(l, instab[l -> insn].ops[0]);
150 lwasm_emit(l, l -> pb);
151 }