intrin.c

   1 /*
   2  * Copyright (C) 2012, 2013
   3  *     Dale Weiler
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a copy of
   6  * this software and associated documentation files (the "Software"), to deal in
   7  * the Software without restriction, including without limitation the rights to
   8  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
   9  * of the Software, and to permit persons to whom the Software is furnished to do
  10  * so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in all
  13  * copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  */
  23 #include <string.h>
  24 #include "parser.h"
  25
  26 /*
  27  * Provides all the "intrinsics" / "builtins" for GMQCC. These can do
  28  * a few things, they can provide fall back implementations for math
  29  * functions if the definitions don't exist for some given engine. Or
  30  * then can determine definitions for existing builtins, and simply
  31  * wrap back to them instead.  This is like a "portable" intrface that
  32  * is entered when -fintrin is used (causing all existing builtins to
  33  * be ignored by the compiler and instead interface through here.
  34  */
  35 #define intrin_ctx(I) parser_ctx((I)->parser)
  36
  37 static GMQCC_INLINE ast_function *intrin_value(intrin_t *intrin, ast_value **out, const char *name, qcint_t vtype) {
  38     ast_value    *value = NULL;
  39     ast_function *func  = NULL;
  40     char          buffer[1024];
  41     char          stype [1024];
  42
  43     util_snprintf(buffer, sizeof(buffer), "__builtin_%s", name);
  44     util_snprintf(stype,  sizeof(stype),   "<%s>",        type_name[vtype]);
  45
  46     value                    = ast_value_new(intrin_ctx(intrin), buffer, TYPE_FUNCTION);
  47     value->intrinsic         = true;
  48     value->expression.next   = (ast_expression*)ast_value_new(intrin_ctx(intrin), stype, vtype);
  49     func                     = ast_function_new(intrin_ctx(intrin), buffer, value);
  50     value->expression.flags |= AST_FLAG_ERASEABLE;
  51
  52     *out = value;
  53     return func;
  54 }
  55
  56 static GMQCC_INLINE void intrin_reg(intrin_t *intrin, ast_value *const value, ast_function *const func) {
  57     vec_push(intrin->parser->functions, func);
  58     vec_push(intrin->parser->globals,   (ast_expression*)value);
  59 }
  60
  61 #define QC_M_E 2.71828182845905f
  62
  63 static ast_expression *intrin_pow (intrin_t *intrin) {
  64     /*
  65      * float pow(float x, float y) {
  66      *   float local = 1.0f;
  67      *   while (y > 0) {
  68      *     while (!(y & 1)) {
  69      *       y >>= 2;
  70      *       x *=  x;
  71      *     }
  72      *     y--;
  73      *     local *= x;
  74      *   }
  75      *   return local;
  76      * }
  77      */
  78     ast_value    *value = NULL;
  79     ast_value    *arg1  = ast_value_new(intrin_ctx(intrin), "x",     TYPE_FLOAT);
  80     ast_value    *arg2  = ast_value_new(intrin_ctx(intrin), "y",     TYPE_FLOAT);
  81     ast_value    *local = ast_value_new(intrin_ctx(intrin), "local", TYPE_FLOAT);
  82     ast_block    *body  = ast_block_new(intrin_ctx(intrin));
  83     ast_block    *l1b   = ast_block_new(intrin_ctx(intrin)); /* loop 1 body */
  84     ast_block    *l2b   = ast_block_new(intrin_ctx(intrin)); /* loop 2 body */
  85     ast_loop     *loop1 = NULL;
  86     ast_loop     *loop2 = NULL;
  87     ast_function *func  = intrin_value(intrin, &value, "pow", TYPE_FLOAT);
  88
  89     /* arguments */
  90     vec_push(value->expression.params, arg1);
  91     vec_push(value->expression.params, arg2);
  92
  93     /* local */
  94     vec_push(body->locals, local);
  95
  96     /* assignment to local of value 1.0f */
  97     vec_push(body->exprs,
  98         (ast_expression*)ast_store_new (
  99             intrin_ctx(intrin),
 100             INSTR_STORE_F,
 101             (ast_expression*)local,
 102             (ast_expression*)intrin->fold->imm_float[1] /* 1 == 1.0f */
 103         )
 104     );
 105
 106     /* y >>= 2 */
 107     vec_push(l2b->exprs,
 108         (ast_expression*)ast_binstore_new (
 109             intrin_ctx(intrin),
 110             INSTR_STORE_F,
 111             INSTR_MUL_F,
 112             (ast_expression*)arg2,
 113             (ast_expression*)fold_constgen_float(intrin->parser->fold, 0.25f)
 114         )
 115     );
 116
 117     /* x *= x */
 118     vec_push(l2b->exprs,
 119         (ast_expression*)ast_binstore_new (
 120             intrin_ctx(intrin),
 121             INSTR_STORE_F,
 122             INSTR_MUL_F,
 123             (ast_expression*)arg1,
 124             (ast_expression*)arg1
 125         )
 126     );
 127
 128     /* while (!(y&1)) */
 129     loop2 = ast_loop_new (
 130         intrin_ctx(intrin),
 131         NULL,
 132         (ast_expression*)ast_binary_new (
 133             intrin_ctx(intrin),
 134             INSTR_AND,
 135             (ast_expression*)arg2,
 136             (ast_expression*)intrin->fold->imm_float[1] /* 1 == 1.0f */
 137         ),
 138         true, /* ! not */
 139         NULL,
 140         false,
 141         NULL,
 142         (ast_expression*)l2b
 143     );
 144
 145     /* push nested loop into loop expressions */
 146     vec_push(l1b->exprs, (ast_expression*)loop2);
 147
 148     /* y-- */
 149     vec_push(l1b->exprs,
 150         (ast_expression*)ast_binstore_new (
 151             intrin_ctx(intrin),
 152             INSTR_STORE_F,
 153             INSTR_SUB_F,
 154             (ast_expression*)arg2,
 155             (ast_expression*)intrin->fold->imm_float[1] /* 1 == 1.0f */
 156         )
 157     );
 158     /* local *= x */
 159     vec_push(l1b->exprs,
 160         (ast_expression*)ast_binstore_new (
 161             intrin_ctx(intrin),
 162             INSTR_STORE_F,
 163             INSTR_MUL_F,
 164             (ast_expression*)local,
 165             (ast_expression*)arg1
 166         )
 167     );
 168
 169     /* while (y > 0) */
 170     loop1 = ast_loop_new (
 171         intrin_ctx(intrin),
 172         NULL,
 173         (ast_expression*)ast_binary_new (
 174             intrin_ctx(intrin),
 175             INSTR_GT,
 176             (ast_expression*)arg2,
 177             (ast_expression*)intrin->fold->imm_float[0] /* 0 == 0.0f */
 178         ),
 179         false,
 180         NULL,
 181         false,
 182         NULL,
 183         (ast_expression*)l1b
 184     );
 185
 186     /* push the loop1 into the body for the function */
 187     vec_push(body->exprs, (ast_expression*)loop1);
 188
 189     /* return local; */
 190     vec_push(body->exprs,
 191         (ast_expression*)ast_return_new (
 192             intrin_ctx(intrin),
 193             (ast_expression*)local
 194         )
 195     );
 196
 197     /* push block and register intrin for codegen */
 198     vec_push(func->blocks, body);
 199
 200     intrin_reg(intrin, value, func);
 201
 202     return (ast_expression*)value;
 203 }
 204
 205 static ast_expression *intrin_mod(intrin_t *intrin) {
 206     /*
 207      * float mod(float x, float y) {
 208      *   return x - y * floor(x / y);
 209      * }
 210      */
 211     ast_value    *value = NULL;
 212     ast_call     *call  = ast_call_new (intrin_ctx(intrin), intrin_func(intrin, "floor"));
 213     ast_value    *arg1  = ast_value_new(intrin_ctx(intrin), "x", TYPE_FLOAT);
 214     ast_value    *arg2  = ast_value_new(intrin_ctx(intrin), "y", TYPE_FLOAT);
 215     ast_block    *body  = ast_block_new(intrin_ctx(intrin));
 216     ast_function *func  = intrin_value(intrin, &value, "mod", TYPE_FLOAT);
 217
 218     /* floor(x/y) */
 219     vec_push(call->params,
 220         (ast_expression*)ast_binary_new (
 221             intrin_ctx(intrin),
 222             INSTR_DIV_F,
 223             (ast_expression*)arg1,
 224             (ast_expression*)arg2
 225         )
 226     );
 227
 228     vec_push(body->exprs,
 229         (ast_expression*)ast_return_new(
 230             intrin_ctx(intrin),
 231             (ast_expression*)ast_binary_new(
 232                 intrin_ctx(intrin),
 233                 INSTR_SUB_F,
 234                 (ast_expression*)arg1,
 235                 (ast_expression*)ast_binary_new(
 236                     intrin_ctx(intrin),
 237                     INSTR_MUL_F,
 238                     (ast_expression*)arg2,
 239                     (ast_expression*)call
 240                 )
 241             )
 242         )
 243     );
 244
 245     vec_push(value->expression.params, arg1); /* float x (for param) */
 246     vec_push(value->expression.params, arg2); /* float y (for param) */
 247
 248     vec_push(func->blocks,             body); /* {{{ body }}} */
 249
 250     intrin_reg(intrin, value, func);
 251
 252     return (ast_expression*)value;
 253 }
 254
 255 static ast_expression *intrin_exp(intrin_t *intrin) {
 256     /*
 257      * float exp(float x) {
 258      *     return pow(QC_M_E, x);
 259      * }
 260      */
 261     ast_value    *value = NULL;
 262     ast_call     *call  = ast_call_new (intrin_ctx(intrin), intrin_func(intrin, "pow"));
 263     ast_value    *arg1  = ast_value_new(intrin_ctx(intrin), "x", TYPE_FLOAT);
 264     ast_block    *body  = ast_block_new(intrin_ctx(intrin));
 265     ast_function *func  = intrin_value(intrin, &value, "exp", TYPE_FLOAT);
 266
 267     /* push arguments for params to call */
 268     vec_push(call->params, (ast_expression*)fold_constgen_float(intrin->fold, QC_M_E));
 269     vec_push(call->params, (ast_expression*)arg1);
 270
 271     /* return pow(QC_M_E, x) */
 272     vec_push(body->exprs,
 273         (ast_expression*)ast_return_new(
 274             intrin_ctx(intrin),
 275             (ast_expression*)call
 276         )
 277     );
 278
 279     vec_push(value->expression.params, arg1); /* float x (for param) */
 280
 281     vec_push(func->blocks,             body); /* {{{ body }}} */
 282
 283     intrin_reg(intrin, value, func);
 284
 285     return (ast_expression*)value;
 286 }
 287
 288 static ast_expression *intrin_isnan(intrin_t *intrin) {
 289     /*
 290      * float isnan(float x) {
 291      *   float local;
 292      *   local = x;
 293      *
 294      *   return (x != local);
 295      * }
 296      */
 297     ast_value    *value  = NULL;
 298     ast_value    *arg1   = ast_value_new(intrin_ctx(intrin), "x",     TYPE_FLOAT);
 299     ast_value    *local  = ast_value_new(intrin_ctx(intrin), "local", TYPE_FLOAT);
 300     ast_block    *body   = ast_block_new(intrin_ctx(intrin));
 301     ast_function *func   = intrin_value(intrin, &value, "isnan", TYPE_FLOAT);
 302
 303     vec_push(body->locals, local);
 304     vec_push(body->exprs,
 305         (ast_expression*)ast_store_new(
 306             intrin_ctx(intrin),
 307             INSTR_STORE_F,
 308             (ast_expression*)local,
 309             (ast_expression*)arg1
 310         )
 311     );
 312
 313     vec_push(body->exprs,
 314         (ast_expression*)ast_return_new(
 315             intrin_ctx(intrin),
 316             (ast_expression*)ast_binary_new(
 317                 intrin_ctx(intrin),
 318                 INSTR_NE_F,
 319                 (ast_expression*)arg1,
 320                 (ast_expression*)local
 321             )
 322         )
 323     );
 324
 325     vec_push(value->expression.params, arg1);
 326     vec_push(func->blocks, body);
 327
 328     intrin_reg(intrin, value, func);
 329
 330     return (ast_expression*)value;
 331 }
 332
 333 static ast_expression *intrin_fabs(intrin_t *intrin) {
 334     /*
 335      * float fabs(float x) {
 336      *     return x < 0 ? -x : x;
 337      * }
 338      */
 339     ast_value    *value  = NULL;
 340     ast_value    *arg1   = ast_value_new(intrin_ctx(intrin), "x", TYPE_FLOAT);
 341     ast_block    *body   = ast_block_new(intrin_ctx(intrin));
 342     ast_function *func   = intrin_value(intrin, &value, "fabs", TYPE_FLOAT);
 343
 344     vec_push(body->exprs,
 345         (ast_expression*)ast_return_new(
 346             intrin_ctx(intrin),
 347             (ast_expression*)ast_ternary_new(
 348                 intrin_ctx(intrin),
 349                 (ast_expression*)ast_binary_new(
 350                     intrin_ctx(intrin),
 351                     INSTR_LE,
 352                     (ast_expression*)arg1,
 353                     (ast_expression*)intrin->fold->imm_float[0]
 354                 ),
 355                 (ast_expression*)ast_binary_new(
 356                     intrin_ctx(intrin),
 357                     INSTR_SUB_F,
 358                     (ast_expression*)intrin->fold->imm_float[0],
 359                     (ast_expression*)arg1
 360                 ),
 361                 (ast_expression*)arg1
 362             )
 363         )
 364     );
 365
 366     vec_push(value->expression.params, arg1);
 367     vec_push(func->blocks, body);
 368
 369     intrin_reg(intrin, value, func);
 370
 371     return (ast_expression*)value;
 372 }
 373
 374 /*
 375  * TODO: make static (and handle ast_type_string) here for the builtin
 376  * instead of in SYA parse close.
 377  */
 378 ast_expression *intrin_debug_typestring(intrin_t *intrin) {
 379     (void)intrin;
 380     return (ast_expression*)0x1;
 381 }
 382
 383 static const intrin_func_t intrinsics[] = {
 384     {&intrin_exp,              "__builtin_exp",              "exp"},
 385     {&intrin_mod,              "__builtin_mod",              "mod"},
 386     {&intrin_pow,              "__builtin_pow",              "pow"},
 387     {&intrin_isnan,            "__builtin_isnan",            "isnan"},
 388     {&intrin_fabs,             "__builtin_fabs",             "fabs"},
 389     {&intrin_debug_typestring, "__builtin_debug_typestring", ""}
 390 };
 391
 392 static void intrin_error(intrin_t *intrin, const char *fmt, ...) {
 393     va_list ap;
 394     va_start(ap, fmt);
 395     vcompile_error(intrin->parser->lex->tok.ctx, fmt, ap);
 396     va_end(ap);
 397 }
 398
 399 /* exposed */
 400 intrin_t *intrin_init(parser_t *parser) {
 401     intrin_t *intrin = (intrin_t*)mem_a(sizeof(intrin_t));
 402     size_t    i;
 403
 404     intrin->parser     = parser;
 405     intrin->fold       = parser->fold;
 406     intrin->intrinsics = NULL;
 407     intrin->generated  = NULL;
 408
 409     vec_append(intrin->intrinsics, GMQCC_ARRAY_COUNT(intrinsics), intrinsics);
 410
 411     /* populate with null pointers for tracking generation */
 412     for (i = 0; i < GMQCC_ARRAY_COUNT(intrinsics); i++)
 413         vec_push(intrin->generated, NULL);
 414
 415     return intrin;
 416 }
 417
 418 void intrin_cleanup(intrin_t *intrin) {
 419     vec_free(intrin->intrinsics);
 420     vec_free(intrin->generated);
 421     mem_d(intrin);
 422 }
 423
 424 ast_expression *intrin_fold(intrin_t *intrin, ast_value *value, ast_expression **exprs) {
 425     size_t i;
 426     if (!value || !value->name)
 427         return NULL;
 428     for (i = 0; i < vec_size(intrin->intrinsics); i++)
 429         if (!strcmp(value->name, intrin->intrinsics[i].name))
 430             return fold_intrin(intrin->fold, value->name + 10, exprs);
 431     return NULL;
 432 }
 433
 434 static GMQCC_INLINE ast_expression *intrin_func_try(intrin_t *intrin, size_t offset, const char *compare) {
 435     size_t i;
 436     for (i = 0; i < vec_size(intrin->intrinsics); i++) {
 437         if (strcmp(*(char **)((char *)&intrin->intrinsics[i] + offset), compare))
 438             continue;
 439         if (intrin->generated[i])
 440             return intrin->generated[i];
 441         return intrin->generated[i] = intrin->intrinsics[i].intrin(intrin);
 442     }
 443     return NULL;
 444 }
 445
 446 ast_expression *intrin_func(intrin_t *intrin, const char *name) {
 447     size_t           i;
 448     ast_expression  *find;
 449
 450     /* try current first */
 451     if ((find = parser_find_global(intrin->parser, name)) && ((ast_value*)find)->expression.vtype == TYPE_FUNCTION)
 452         for (i = 0; i < vec_size(intrin->parser->functions); ++i)
 453             if (((ast_value*)find)->name && !strcmp(intrin->parser->functions[i]->name, ((ast_value*)find)->name) && intrin->parser->functions[i]->builtin < 0)
 454                 return find;
 455     /* try name second */
 456     if ((find = intrin_func_try(intrin, offsetof(intrin_func_t, name),  name)))
 457         return find;
 458     /* try alias third */
 459     if ((find = intrin_func_try(intrin, offsetof(intrin_func_t, alias), name)))
 460         return find;
 461
 462     intrin_error(intrin, "need function: `%s` compiler depends on it", name);
 463     return NULL;
 464 }