1/* Process machine description and calculate constant conditions. 2 Copyright (C) 2001-2015 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3, or (at your option) 9 any later version. 10 11 GCC is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20/* In a machine description, all of the insn patterns - define_insn, 21 define_expand, define_split, define_peephole, define_peephole2 - 22 contain an optional C expression which makes the final decision 23 about whether or not this pattern is usable. That expression may 24 turn out to be always false when the compiler is built. If it is, 25 most of the programs that generate code from the machine 26 description can simply ignore the entire pattern. */ 27 28#include "bconfig.h" 29#include "system.h" 30#include "coretypes.h" 31#include "tm.h" 32#include "rtl.h" 33#include "errors.h" 34#include "hashtab.h" 35#include "read-md.h" 36#include "gensupport.h" 37 38/* so we can include except.h in the generated file. */ 39static int saw_eh_return; 40 41static void write_header (void); 42static void write_conditions (void); 43static int write_one_condition (void **, void *); 44 45/* Generate the header for insn-conditions.c. */ 46 47static void 48write_header (void) 49{ 50 puts ("\ 51/* Generated automatically by the program `genconditions' from the target\n\ 52 machine description file. */\n\ 53\n\ 54#include \"bconfig.h\"\n\ 55#include \"system.h\"\n\ 56\n\ 57/* It is necessary, but not entirely safe, to include the headers below\n\ 58 in a generator program. As a defensive measure, don't do so when the\n\ 59 table isn't going to have anything in it. */\n\ 60#if GCC_VERSION >= 3001\n\ 61\n\ 62/* Do not allow checking to confuse the issue. */\n\ 63#undef ENABLE_CHECKING\n\ 64#undef ENABLE_TREE_CHECKING\n\ 65#undef ENABLE_RTL_CHECKING\n\ 66#undef ENABLE_RTL_FLAG_CHECKING\n\ 67#undef ENABLE_GC_CHECKING\n\ 68#undef ENABLE_GC_ALWAYS_COLLECT\n\ 69\n\ 70#include \"coretypes.h\"\n\ 71#include \"tm.h\"\n\ 72#include \"insn-constants.h\"\n\ 73#include \"ggc.h\"\n\ 74#include \"rtl.h\"\n\ 75#include \"tm_p.h\"\n\ 76#include \"hashtab.h\"\n\ 77#include \"hash-set.h\"\n\ 78#include \"hard-reg-set.h\"\n\ 79#include \"function.h\"\n\ 80\n\ 81/* Fake - insn-config.h doesn't exist yet. */\n\ 82#define MAX_RECOG_OPERANDS 10\n\ 83#define MAX_DUP_OPERANDS 10\n\ 84#define MAX_INSNS_PER_SPLIT 5\n\ 85\n\ 86#include \"regs.h\"\n\ 87#include \"recog.h\"\n\ 88#include \"output.h\"\n\ 89#include \"flags.h\"\n\ 90#include \"hard-reg-set.h\"\n\ 91#include \"predict.h\"\n\ 92#include \"basic-block.h\"\n\ 93#include \"resource.h\"\n\ 94#include \"diagnostic-core.h\"\n\ 95#include \"reload.h\"\n\ 96#include \"tm-constrs.h\"\n"); 97 98 if (saw_eh_return) 99 puts ("#define HAVE_eh_return 1"); 100 puts ("#include \"except.h\"\n"); 101 102 puts ("\ 103/* Dummy external declarations. */\n\ 104extern rtx_insn *insn;\n\ 105extern rtx ins1;\n\ 106extern rtx operands[];\n\ 107\n\ 108#endif /* gcc >= 3.0.1 */\n"); 109} 110 111/* Write out one entry in the conditions table, using the data pointed 112 to by SLOT. Each entry looks like this: 113 114 { "! optimize_size && ! TARGET_READ_MODIFY_WRITE", 115 __builtin_constant_p (! optimize_size && ! TARGET_READ_MODIFY_WRITE) 116 ? (int) (! optimize_size && ! TARGET_READ_MODIFY_WRITE) 117 : -1) }, */ 118 119static int 120write_one_condition (void **slot, void * ARG_UNUSED (dummy)) 121{ 122 const struct c_test *test = * (const struct c_test **) slot; 123 const char *p; 124 125 print_md_ptr_loc (test->expr); 126 fputs (" { \"", stdout); 127 for (p = test->expr; *p; p++) 128 { 129 switch (*p) 130 { 131 case '\n': fputs ("\\n\\", stdout); break; 132 case '\\': 133 case '\"': putchar ('\\'); break; 134 default: break; 135 } 136 putchar (*p); 137 } 138 139 fputs ("\",\n __builtin_constant_p ", stdout); 140 print_c_condition (test->expr); 141 fputs ("\n ? (int) ", stdout); 142 print_c_condition (test->expr); 143 fputs ("\n : -1 },\n", stdout); 144 return 1; 145} 146 147/* Write out the complete conditions table, its size, and a flag 148 indicating that gensupport.c can now do insn elision. */ 149static void 150write_conditions (void) 151{ 152 puts ("\ 153/* Structure definition duplicated from gensupport.h rather than\n\ 154 drag in that file and its dependencies. */\n\ 155struct c_test\n\ 156{\n\ 157 const char *expr;\n\ 158 int value;\n\ 159};\n\ 160\n\ 161/* This table lists each condition found in the machine description.\n\ 162 Each condition is mapped to its truth value (0 or 1), or -1 if that\n\ 163 cannot be calculated at compile time.\n\ 164 If we don't have __builtin_constant_p, or it's not acceptable in array\n\ 165 initializers, fall back to assuming that all conditions potentially\n\ 166 vary at run time. It works in 3.0.1 and later; 3.0 only when not\n\ 167 optimizing. */\n\ 168\n\ 169#if GCC_VERSION >= 3001\n\ 170static const struct c_test insn_conditions[] = {\n"); 171 172 traverse_c_tests (write_one_condition, 0); 173 174 puts ("\n};\n#endif /* gcc >= 3.0.1 */\n"); 175} 176 177/* Emit code which will convert the C-format table to a 178 (define_conditions) form, which the MD reader can understand. 179 The result will be added to the set of files scanned by 180 'downstream' generators. */ 181static void 182write_writer (void) 183{ 184 puts ("int\n" 185 "main(void)\n" 186 "{\n" 187 " unsigned int i;\n" 188 " const char *p;\n" 189 " puts (\"(define_conditions [\");\n" 190 "#if GCC_VERSION >= 3001\n" 191 " for (i = 0; i < ARRAY_SIZE (insn_conditions); i++)\n" 192 " {\n" 193 " printf (\" (%d \\\"\", insn_conditions[i].value);\n" 194 " for (p = insn_conditions[i].expr; *p; p++)\n" 195 " {\n" 196 " switch (*p)\n" 197 " {\n" 198 " case '\\\\':\n" 199 " case '\\\"': putchar ('\\\\'); break;\n" 200 " default: break;\n" 201 " }\n" 202 " putchar (*p);\n" 203 " }\n" 204 " puts (\"\\\")\");\n" 205 " }\n" 206 "#endif /* gcc >= 3.0.1 */\n" 207 " puts (\"])\");\n" 208 " fflush (stdout);\n" 209 "return ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE;\n" 210 "}"); 211} 212 213int 214main (int argc, char **argv) 215{ 216 rtx desc; 217 int pattern_lineno; /* not used */ 218 int code; 219 220 progname = "genconditions"; 221 222 if (!init_rtx_reader_args (argc, argv)) 223 return (FATAL_EXIT_CODE); 224 225 /* Read the machine description. */ 226 while (1) 227 { 228 desc = read_md_rtx (&pattern_lineno, &code); 229 if (desc == NULL) 230 break; 231 232 /* N.B. define_insn_and_split, define_cond_exec are handled 233 entirely within read_md_rtx; we never see them. */ 234 switch (GET_CODE (desc)) 235 { 236 default: 237 break; 238 239 case DEFINE_INSN: 240 case DEFINE_EXPAND: 241 add_c_test (XSTR (desc, 2), -1); 242 /* except.h needs to know whether there is an eh_return 243 pattern in the machine description. */ 244 if (!strcmp (XSTR (desc, 0), "eh_return")) 245 saw_eh_return = 1; 246 break; 247 248 case DEFINE_SPLIT: 249 case DEFINE_PEEPHOLE: 250 case DEFINE_PEEPHOLE2: 251 add_c_test (XSTR (desc, 1), -1); 252 break; 253 } 254 } 255 256 write_header (); 257 write_conditions (); 258 write_writer (); 259 260 fflush (stdout); 261 return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE); 262} 263