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Initial import from lwtools 3.0.1 version, with new hand built build system and file reorganization
author lost@l-w.ca
date Wed, 19 Jan 2011 22:27:17 -0700
parents
children 09021ba6d755
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-1:000000000000 0:2c24602be78f
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 <ctype.h>
22 #include <string.h>
23
24 #include "lwasm.h"
25 #include "instab.h"
26
27 PARSEFUNC(insn_parse_tfm)
28 {
29 static const char *reglist = "DXYUS AB 00EF";
30 int r0, r1;
31 char *c;
32 int tfm = 0;
33
34 c = strchr(reglist, toupper(*(*p)++));
35 if (!c)
36 {
37 lwasm_register_error(as, l, "Unknown operation");
38 return;
39 }
40 r0 = c - reglist;
41 if (**p == '+')
42 {
43 (*p)++;
44 tfm = 1;
45 }
46 else if (**p == '-')
47 {
48 (*p)++;
49 tfm = 2;
50 }
51 if (*(*p)++ != ',')
52 {
53 lwasm_register_error(as, l, "Unknown operation");
54 return;
55 }
56 c = strchr(reglist, toupper(*(*p)++));
57 if (!c)
58 {
59 lwasm_register_error(as, l, "Unknown operation");
60 return;
61 }
62 r1 = c - reglist;
63
64 if (**p == '+')
65 {
66 (*p)++;
67 tfm |= 4;
68 }
69 else if (**p == '-')
70 {
71 (*p)++;
72 tfm |= 8;
73 }
74
75 if (**p && !isspace(**p))
76 {
77 lwasm_register_error(as, l, "Bad operand");
78 return;
79 }
80
81 // valid values of tfm here are:
82 // 1: r0+,r1 (2)
83 // 4: r0,r1+ (3)
84 // 5: r0+,r1+ (0)
85 // 10: r0-,r1- (1)
86 switch (tfm)
87 {
88 case 5: //r0+,r1+
89 l -> lint = instab[l -> insn].ops[0];
90 break;
91
92 case 10: //r0-,r1-
93 l -> lint = instab[l -> insn].ops[1];
94 break;
95
96 case 1: // r0+,r1
97 l -> lint = instab[l -> insn].ops[2];
98 break;
99
100 case 4: // r0,r1+
101 l -> lint = instab[l -> insn].ops[3];
102 break;
103
104 default:
105 lwasm_register_error(as, l, "Unknown operation");
106 return;
107 }
108 l -> pb = (r0 << 4) | r1;
109 l -> len = OPLEN(l -> lint);
110 }
111
112 EMITFUNC(insn_emit_tfm)
113 {
114 lwasm_emitop(l, l -> lint);
115 lwasm_emit(l, l -> pb);
116 }
117
118 PARSEFUNC(insn_parse_tfmrtor)
119 {
120 int r0, r1;
121 static const char *regs = "D X Y U S A B 0 0 E F ";
122
123 // register to register (r0,r1)
124 // registers are in order:
125 // D,X,Y,U,S,PC,W,V
126 // A,B,CC,DP,0,0,E,F
127 r0 = lwasm_lookupreg2(regs, p);
128 if (r0 < 0 || *(*p)++ != ',')
129 {
130 lwasm_register_error(as, l, "Bad operand");
131 r0 = r1 = 0;
132 }
133 else
134 {
135 r1 = lwasm_lookupreg2(regs, p);
136 if (r1 < 0)
137 {
138 lwasm_register_error(as, l, "Bad operand");
139 r0 = r1 = 0;
140 }
141 }
142 l -> len = instab[l -> insn].ops[0] + 1;
143 l -> pb = (r0 << 4) | r1;
144 }
145
146 EMITFUNC(insn_emit_tfmrtor)
147 {
148 lwasm_emitop(l, instab[l -> insn].ops[0]);
149 lwasm_emit(l, l -> pb);
150 }