1/* Generate from machine description:
2 - some flags HAVE_... saying which simple standard instructions are
3 available for this machine.
4 Copyright (C) 1987-2025 Free Software Foundation, Inc.
5
6This file is part of GCC.
7
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 3, or (at your option) any later
11version.
12
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16for more details.
17
18You should have received a copy of the GNU General Public License
19along with GCC; see the file COPYING3. If not see
20<http://www.gnu.org/licenses/>. */
21
22
23#include "bconfig.h"
24#include "system.h"
25#include "coretypes.h"
26#include "tm.h"
27#include "rtl.h"
28#include "obstack.h"
29#include "errors.h"
30#include "read-md.h"
31#include "gensupport.h"
32
33/* Obstack to remember insns with. */
34static struct obstack obstack;
35
36/* Max size of names encountered. */
37static int max_id_len;
38
39/* Max operand encountered in a scan over some insn. */
40static int max_opno;
41
42static void max_operand_1 (rtx);
43static int num_operands (rtx);
44static void gen_proto (rtx);
45
46/* Count the number of match_operand's found. */
47
48static void
49max_operand_1 (rtx x)
50{
51 RTX_CODE code;
52 int i;
53 int len;
54 const char *fmt;
55
56 if (x == 0)
57 return;
58
59 code = GET_CODE (x);
60
61 if (code == MATCH_OPERAND || code == MATCH_OPERATOR
62 || code == MATCH_PARALLEL)
63 max_opno = MAX (max_opno, XINT (x, 0));
64
65 fmt = GET_RTX_FORMAT (code);
66 len = GET_RTX_LENGTH (code);
67 for (i = 0; i < len; i++)
68 {
69 if (fmt[i] == 'e' || fmt[i] == 'u')
70 max_operand_1 (XEXP (x, i));
71 else if (fmt[i] == 'E')
72 {
73 int j;
74 for (j = 0; j < XVECLEN (x, i); j++)
75 max_operand_1 (XVECEXP (x, i, j));
76 }
77 }
78}
79
80static int
81num_operands (rtx insn)
82{
83 int len = XVECLEN (insn, 1);
84 int i;
85
86 max_opno = -1;
87
88 for (i = 0; i < len; i++)
89 max_operand_1 (XVECEXP (insn, 1, i));
90
91 return max_opno + 1;
92}
93
94/* Print out prototype information for a generator function. If the
95 insn pattern has been elided, print out a dummy generator that
96 does nothing. */
97
98static void
99gen_proto (rtx insn)
100{
101 int num = num_operands (insn);
102 int i;
103 const char *name = XSTR (insn, 0);
104 int truth = maybe_eval_c_test (XSTR (insn, 2));
105
106 if (truth != 0)
107 printf (format: "extern rtx gen_%-*s (", max_id_len, name);
108 else
109 printf (format: "static inline rtx gen_%-*s (", max_id_len, name);
110
111 if (num == 0)
112 fputs ("void", stdout);
113 else
114 {
115 for (i = 1; i < num; i++)
116 fputs ("rtx, ", stdout);
117
118 fputs ("rtx", stdout);
119 }
120
121 puts (s: ");");
122
123 /* Some back ends want to take the address of generator functions,
124 so we cannot simply use #define for these dummy definitions. */
125 if (truth == 0)
126 {
127 printf (format: "static inline rtx\ngen_%s", name);
128 if (num > 0)
129 {
130 putchar ('(');
131 for (i = 0; i < num-1; i++)
132 printf (format: "rtx ARG_UNUSED (%c), ", 'a' + i);
133 printf (format: "rtx ARG_UNUSED (%c))\n", 'a' + i);
134 }
135 else
136 puts (s: "(void)");
137 puts (s: "{\n return 0;\n}");
138 }
139
140}
141
142static void
143gen_insn (md_rtx_info *info)
144{
145 rtx insn = info->def;
146 const char *name = XSTR (insn, 0);
147 const char *p;
148 const char *lt, *gt;
149 int len;
150 int truth = maybe_eval_c_test (XSTR (insn, 2));
151
152 lt = strchr (s: name, c: '<');
153 if (lt && strchr (s: lt + 1, c: '>'))
154 {
155 error_at (info->loc, "unresolved iterator in %s", name);
156 return;
157 }
158
159 gt = strchr (s: name, c: '>');
160 if (lt || gt)
161 {
162 error_at (info->loc, "unmatched angle brackets, likely "
163 "an error in iterator syntax in %s", name);
164 return;
165 }
166
167 /* Don't mention instructions whose names are the null string
168 or begin with '*'. They are in the machine description just
169 to be recognized. */
170 if (name[0] == 0 || name[0] == '*')
171 return;
172
173 len = strlen (s: name);
174
175 if (len > max_id_len)
176 max_id_len = len;
177
178 if (truth == 0)
179 /* Emit nothing. */;
180 else if (truth == 1)
181 printf (format: "#define HAVE_%s 1\n", name);
182 else
183 {
184 /* Write the macro definition, putting \'s at the end of each line,
185 if more than one. */
186 printf (format: "#define HAVE_%s (", name);
187 for (p = XSTR (insn, 2); *p; p++)
188 {
189 if (IS_VSPACE (*p))
190 fputs (" \\\n", stdout);
191 else
192 putchar (*p);
193 }
194 fputs (")\n", stdout);
195 }
196
197 obstack_grow (&obstack, &insn, sizeof (rtx));
198}
199
200int
201main (int argc, const char **argv)
202{
203 rtx dummy;
204 rtx *insns;
205 rtx *insn_ptr;
206
207 progname = "genflags";
208 obstack_init (&obstack);
209
210 /* We need to see all the possibilities. Elided insns may have
211 direct calls to their generators in C code. */
212 insn_elision = 0;
213
214 if (!init_rtx_reader_args (argc, argv))
215 return (FATAL_EXIT_CODE);
216
217 puts (s: "/* Generated automatically by the program `genflags'");
218 puts (s: " from the machine description file `md'. */\n");
219 puts (s: "#ifndef GCC_INSN_FLAGS_H");
220 puts (s: "#define GCC_INSN_FLAGS_H\n");
221
222 /* Read the machine description. */
223
224 md_rtx_info info;
225 while (read_md_rtx (&info))
226 switch (GET_CODE (info.def))
227 {
228 case DEFINE_INSN:
229 case DEFINE_EXPAND:
230 gen_insn (info: &info);
231 break;
232
233 default:
234 break;
235 }
236
237 /* Print out the prototypes now. */
238 dummy = (rtx) 0;
239 obstack_grow (&obstack, &dummy, sizeof (rtx));
240 insns = XOBFINISH (&obstack, rtx *);
241
242 for (insn_ptr = insns; *insn_ptr; insn_ptr++)
243 gen_proto (insn: *insn_ptr);
244
245 puts (s: "\n#endif /* GCC_INSN_FLAGS_H */");
246
247 if (have_error || ferror (stdout) || fflush (stdout) || fclose (stdout))
248 return FATAL_EXIT_CODE;
249
250 return SUCCESS_EXIT_CODE;
251}
252

source code of gcc/genflags.cc