show-parse.c

   1 /*
   2  * sparse/show-parse.c
   3  *
   4  * Copyright (C) 2003 Transmeta Corp.
   5  *               2003-2004 Linus Torvalds
   6  *
   7  *  Licensed under the Open Software License version 1.1
   8  *
   9  * Print out results of parsing for debugging and testing.
  10  */
  11 #include <stdarg.h>
  12 #include <stdlib.h>
  13 #include <stdio.h>
  14 #include <string.h>
  15 #include <ctype.h>
  16 #include <unistd.h>
  17 #include <fcntl.h>
  18
  19 #include "lib.h"
  20 #include "allocate.h"
  21 #include "token.h"
  22 #include "parse.h"
  23 #include "symbol.h"
  24 #include "scope.h"
  25 #include "expression.h"
  26 #include "target.h"
  27
  28 static int show_symbol_expr(struct symbol *sym);
  29 static int show_string_expr(struct expression *expr);
  30
  31 static void do_debug_symbol(struct symbol *sym, int indent)
  32 {
  33         static const char indent_string[] = "                                  ";
  34         static const char *typestr[] = {
  35                 [SYM_UNINITIALIZED] = "none",
  36                 [SYM_PREPROCESSOR] = "cpp.",
  37                 [SYM_BASETYPE] = "base",
  38                 [SYM_NODE] = "node",
  39                 [SYM_PTR] = "ptr.",
  40                 [SYM_FN] = "fn..",
  41                 [SYM_ARRAY] = "arry",
  42                 [SYM_STRUCT] = "strt",
  43                 [SYM_UNION] = "unin",
  44                 [SYM_ENUM] = "enum",
  45                 [SYM_TYPEDEF] = "tdef",
  46                 [SYM_TYPEOF] = "tpof",
  47                 [SYM_MEMBER] = "memb",
  48                 [SYM_BITFIELD] = "bitf",
  49                 [SYM_LABEL] = "labl",
  50                 [SYM_RESTRICT] = "rstr",
  51                 [SYM_BAD] = "bad.",
  52         };
  53
  54         if (!sym)
  55                 return;
  56         fprintf(stderr, "%.*s%s%3d:%lu %lx %s (as: %d, context: %x:%x) %p (%s:%d:%d)\n",
  57                 indent, indent_string, typestr[sym->type],
  58                 sym->bit_size, sym->ctype.alignment,
  59                 sym->ctype.modifiers, show_ident(sym->ident),
  60                 sym->ctype.as, sym->ctype.in_context, sym->ctype.out_context,
  61                 sym, stream_name(sym->pos.stream), sym->pos.line, sym->pos.pos);
  62         if (sym->type == SYM_FN) {
  63                 int i = 1;
  64                 struct symbol *arg;
  65                 FOR_EACH_PTR(sym->arguments, arg) {
  66                         fprintf(stderr, "< arg%d:\n", i);
  67                         do_debug_symbol(arg, 0);
  68                         fprintf(stderr, "  end arg%d >\n", i);
  69                         i++;
  70                 } END_FOR_EACH_PTR(arg);
  71         }
  72         do_debug_symbol(sym->ctype.base_type, indent+2);
  73 }
  74
  75 void debug_symbol(struct symbol *sym)
  76 {
  77         do_debug_symbol(sym, 0);
  78 }
  79
  80 /*
  81  * Symbol type printout. The type system is by far the most
  82  * complicated part of C - everything else is trivial.
  83  */
  84 const char *modifier_string(unsigned long mod)
  85 {
  86         static char buffer[100];
  87         char *p = buffer;
  88         const char *res,**ptr, *names[] = {
  89                 "auto", "register", "static", "extern",
  90                 "const", "volatile", "[signed]", "[unsigned]",
  91                 "[char]", "[short]", "[long]", "[long]",
  92                 "[typdef]", "[structof]", "[unionof]", "[enum]",
  93                 "[typeof]", "[attribute]", "inline", "[addressable]",
  94                 "[nocast]", "[noderef]", "[accessed]", "[toplevel]",
  95                 "[label]", "[assigned]", "[type]", "[safe]",
  96                 "[usertype]", "[force]", "[explicitly-signed]",
  97                 NULL
  98         };
  99         ptr = names;
 100         while ((res = *ptr++) != NULL) {
 101                 if (mod & 1) {
 102                         char c;
 103                         while ((c = *res++) != '\0')
 104                                 *p++ = c;
 105                         *p++ = ' ';
 106                 }
 107                 mod >>= 1;
 108         }
 109         *p = 0;
 110         return buffer;
 111 }
 112
 113 void show_struct_member(struct symbol *sym)
 114 {
 115         printf("\t%s:%d:%ld at offset %ld.%d", show_ident(sym->ident), sym->bit_size, sym->ctype.alignment, sym->offset, sym->bit_offset);
 116         printf("\n");
 117 }
 118
 119 void show_symbol_list(struct symbol_list *list, const char *sep)
 120 {
 121         struct symbol *sym;
 122         const char *prepend = "";
 123
 124         FOR_EACH_PTR(list, sym) {
 125                 puts(prepend);
 126                 prepend = ", ";
 127                 show_symbol(sym);
 128         } END_FOR_EACH_PTR(sym);
 129 }
 130
 131 struct type_name {
 132         char *start;
 133         char *end;
 134 };
 135
 136 static void prepend(struct type_name *name, const char *fmt, ...)
 137 {
 138         static char buffer[512];
 139         int n;
 140
 141         va_list args;
 142         va_start(args, fmt);
 143         n = vsprintf(buffer, fmt, args);
 144         va_end(args);
 145
 146         name->start -= n;
 147         memcpy(name->start, buffer, n);
 148 }
 149
 150 static void append(struct type_name *name, const char *fmt, ...)
 151 {
 152         static char buffer[512];
 153         int n;
 154
 155         va_list args;
 156         va_start(args, fmt);
 157         n = vsprintf(buffer, fmt, args);
 158         va_end(args);
 159
 160         memcpy(name->end, buffer, n);
 161         name->end += n;
 162 }
 163
 164 static void do_show_type(struct symbol *sym, struct type_name *name)
 165 {
 166         int i, modlen;
 167         const char *mod;
 168         static struct ctype_name {
 169                 struct symbol *sym;
 170                 const char *name;
 171         } typenames[] = {
 172                 { & char_ctype,  "char" },
 173                 { &schar_ctype,  "signed char" },
 174                 { &uchar_ctype,  "unsigned char" },
 175                 { & short_ctype, "short" },
 176                 { &sshort_ctype, "signed short" },
 177                 { &ushort_ctype, "unsigned short" },
 178                 { & int_ctype,   "int" },
 179                 { &sint_ctype,   "signed int" },
 180                 { &uint_ctype,   "unsigned int" },
 181                 { &slong_ctype,  "signed long" },
 182                 { & long_ctype,  "long" },
 183                 { &ulong_ctype,  "unsigned long" },
 184                 { & llong_ctype, "long long" },
 185                 { &sllong_ctype, "signed long long" },
 186                 { &ullong_ctype, "unsigned long long" },
 187
 188                 { &void_ctype,   "void" },
 189                 { &bool_ctype,   "bool" },
 190                 { &string_ctype, "string" },
 191
 192                 { &float_ctype,  "float" },
 193                 { &double_ctype, "double" },
 194                 { &ldouble_ctype,"long double" },
 195                 { &incomplete_ctype, "incomplete type" },
 196                 { &label_ctype, "label type" },
 197                 { &bad_ctype, "bad type" },
 198         };
 199
 200         if (!sym)
 201                 return;
 202
 203         for (i = 0; i < sizeof(typenames)/sizeof(typenames[0]); i++) {
 204                 if (typenames[i].sym == sym) {
 205                         int len = strlen(typenames[i].name);
 206                         *--name->start = ' ';
 207                         name->start -= len;
 208                         memcpy(name->start, typenames[i].name, len);
 209                         return;
 210                 }
 211         }
 212
 213         /* Prepend */
 214         switch (sym->type) {
 215         case SYM_PTR:
 216                 prepend(name, "*");
 217                 break;
 218         case SYM_FN:
 219                 prepend(name, "( ");
 220                 break;
 221         case SYM_STRUCT:
 222                 prepend(name, "struct %s ", show_ident(sym->ident));
 223                 return;
 224
 225         case SYM_UNION:
 226                 prepend(name, "union %s ", show_ident(sym->ident));
 227                 return;
 228
 229         case SYM_ENUM:
 230                 prepend(name, "enum %s ", show_ident(sym->ident));
 231                 break;
 232
 233         case SYM_NODE:
 234                 append(name, "%s", show_ident(sym->ident));
 235                 break;
 236
 237         case SYM_BITFIELD:
 238                 append(name, ":%d", sym->bit_size);
 239                 break;
 240
 241         case SYM_LABEL:
 242                 append(name, "label(%s:%p)", show_ident(sym->ident), sym);
 243                 break;
 244
 245         case SYM_ARRAY:
 246                 break;
 247
 248         case SYM_RESTRICT:
 249                 break;
 250
 251         default:
 252                 prepend(name, "unknown type %d", sym->type);
 253                 return;
 254         }
 255
 256         mod = modifier_string(sym->ctype.modifiers);
 257         modlen = strlen(mod);
 258         name->start -= modlen;
 259         memcpy(name->start, mod, modlen);
 260
 261         do_show_type(sym->ctype.base_type, name);
 262
 263         /* Postpend */
 264         if (sym->ctype.as)
 265                 append(name, "<asn:%d>", sym->ctype.as);
 266
 267         switch (sym->type) {
 268         case SYM_PTR:
 269                 return;
 270
 271         case SYM_FN:
 272                 append(name, " )( ... )");
 273                 return;
 274
 275         case SYM_ARRAY:
 276                 append(name, "[%lld]", get_expression_value(sym->array_size));
 277                 return;
 278
 279         case SYM_RESTRICT:
 280                 prepend(name, "restricted ");
 281                 return;
 282
 283         default:
 284                 break;
 285         }
 286 }
 287
 288 void show_type(struct symbol *sym)
 289 {
 290         char array[200];
 291         struct type_name name;
 292
 293         name.start = name.end = array+100;
 294         do_show_type(sym, &name);
 295         *name.end = 0;
 296         printf("%s", name.start);
 297 }
 298
 299 const char *show_typename(struct symbol *sym)
 300 {
 301         static char array[200];
 302         struct type_name name;
 303
 304         name.start = name.end = array+100;
 305         do_show_type(sym, &name);
 306         *name.end = 0;
 307         return name.start;
 308 }
 309
 310 void show_symbol(struct symbol *sym)
 311 {
 312         struct symbol *type;
 313
 314         if (!sym)
 315                 return;
 316
 317         if (sym->ctype.alignment)
 318                 printf(".align %ld\n", sym->ctype.alignment);
 319
 320         show_type(sym);
 321         type = sym->ctype.base_type;
 322         if (!type)
 323                 return;
 324
 325         /*
 326          * Show actual implementation information
 327          */
 328         switch (type->type) {
 329                 struct symbol *member;
 330
 331         case SYM_STRUCT:
 332         case SYM_UNION:
 333                 printf(" {\n");
 334                 FOR_EACH_PTR(type->symbol_list, member) {
 335                         show_struct_member(member);
 336                 } END_FOR_EACH_PTR(member);
 337                 printf("}\n");
 338                 break;
 339
 340         case SYM_FN: {
 341                 struct statement *stmt = type->stmt;
 342                 if (stmt) {
 343                         int val;
 344                         printf("\n");
 345                         val = show_statement(stmt);
 346                         if (val)
 347                                 printf("\tmov.%d\t\tretval,%d\n", stmt->ret->bit_size, val);
 348                         printf("\tret\n");
 349                 }
 350                 break;
 351         }
 352
 353         default:
 354                 break;
 355         }
 356
 357         if (sym->initializer) {
 358                 printf(" = \n");
 359                 show_expression(sym->initializer);
 360         }
 361 }
 362
 363 static int show_symbol_init(struct symbol *sym);
 364
 365 static int new_pseudo(void)
 366 {
 367         static int nr = 0;
 368         return ++nr;
 369 }
 370
 371 static int new_label(void)
 372 {
 373         static int label = 0;
 374         return ++label;
 375 }
 376
 377 static void show_switch_statement(struct statement *stmt)
 378 {
 379         int val = show_expression(stmt->switch_expression);
 380         struct symbol *sym;
 381         printf("\tswitch v%d\n", val);
 382
 383         /*
 384          * Debugging only: Check that the case list is correct
 385          * by printing it out.
 386          *
 387          * This is where a _real_ back-end would go through the
 388          * cases to decide whether to use a lookup table or a
 389          * series of comparisons etc
 390          */
 391         printf("# case table:\n");
 392         FOR_EACH_PTR(stmt->switch_case->symbol_list, sym) {
 393                 struct statement *case_stmt = sym->stmt;
 394                 struct expression *expr = case_stmt->case_expression;
 395                 struct expression *to = case_stmt->case_to;
 396
 397                 if (!expr) {
 398                         printf("    default");
 399                 } else {
 400                         if (expr->type == EXPR_VALUE) {
 401                                 printf("    case %lld", expr->value);
 402                                 if (to) {
 403                                         if (to->type == EXPR_VALUE) {
 404                                                 printf(" .. %lld", to->value);
 405                                         } else {
 406                                                 printf(" .. what?");
 407                                         }
 408                                 }
 409                         } else
 410                                 printf("    what?");
 411                 }
 412                 printf(": .L%p\n", sym->bb_target);
 413         } END_FOR_EACH_PTR(sym);
 414         printf("# end case table\n");
 415
 416         show_statement(stmt->switch_statement);
 417
 418         if (stmt->switch_break->used)
 419                 printf(".L%p:\n", stmt->switch_break->bb_target);
 420 }
 421
 422 static void show_symbol_decl(struct symbol_list *syms)
 423 {
 424         struct symbol *sym;
 425         FOR_EACH_PTR(syms, sym) {
 426                 show_symbol_init(sym);
 427         } END_FOR_EACH_PTR(sym);
 428 }
 429
 430 static int show_return_stmt(struct statement *stmt);
 431
 432 /*
 433  * Print out a statement
 434  */
 435 int show_statement(struct statement *stmt)
 436 {
 437         if (!stmt)
 438                 return 0;
 439         switch (stmt->type) {
 440         case STMT_RETURN:
 441                 return show_return_stmt(stmt);
 442         case STMT_COMPOUND: {
 443                 struct statement *s;
 444                 int last = 0;
 445
 446                 show_symbol_decl(stmt->syms);
 447                 FOR_EACH_PTR(stmt->stmts, s) {
 448                         last = show_statement(s);
 449                 } END_FOR_EACH_PTR(s);
 450                 if (stmt->ret) {
 451                         int addr, bits;
 452                         printf(".L%p:\n", stmt->ret);
 453                         addr = show_symbol_expr(stmt->ret);
 454                         bits = stmt->ret->bit_size;
 455                         last = new_pseudo();
 456                         printf("\tld.%d\t\tv%d,[v%d]\n", bits, last, addr);
 457                 }
 458                 return last;
 459         }
 460
 461         case STMT_EXPRESSION:
 462                 return show_expression(stmt->expression);
 463         case STMT_IF: {
 464                 int val, target;
 465                 struct expression *cond = stmt->if_conditional;
 466
 467 /* This is only valid if nobody can jump into the "dead" statement */
 468 #if 0
 469                 if (cond->type == EXPR_VALUE) {
 470                         struct statement *s = stmt->if_true;
 471                         if (!cond->value)
 472                                 s = stmt->if_false;
 473                         show_statement(s);
 474                         break;
 475                 }
 476 #endif
 477                 val = show_expression(cond);
 478                 target = new_label();
 479                 printf("\tje\t\tv%d,.L%d\n", val, target);
 480                 show_statement(stmt->if_true);
 481                 if (stmt->if_false) {
 482                         int last = new_label();
 483                         printf("\tjmp\t\t.L%d\n", last);
 484                         printf(".L%d:\n", target);
 485                         target = last;
 486                         show_statement(stmt->if_false);
 487                 }
 488                 printf(".L%d:\n", target);
 489                 break;
 490         }
 491         case STMT_SWITCH:
 492                 show_switch_statement(stmt);
 493                 break;
 494
 495         case STMT_CASE:
 496                 printf(".L%p:\n", stmt->case_label);
 497                 show_statement(stmt->case_statement);
 498                 break;
 499
 500         case STMT_ITERATOR: {
 501                 struct statement  *pre_statement = stmt->iterator_pre_statement;
 502                 struct expression *pre_condition = stmt->iterator_pre_condition;
 503                 struct statement  *statement = stmt->iterator_statement;
 504                 struct statement  *post_statement = stmt->iterator_post_statement;
 505                 struct expression *post_condition = stmt->iterator_post_condition;
 506                 int val, loop_top = 0, loop_bottom = 0;
 507
 508                 show_symbol_decl(stmt->iterator_syms);
 509                 show_statement(pre_statement);
 510                 if (pre_condition) {
 511                         if (pre_condition->type == EXPR_VALUE) {
 512                                 if (!pre_condition->value) {
 513                                         loop_bottom = new_label();
 514                                         printf("\tjmp\t\t.L%d\n", loop_bottom);
 515                                 }
 516                         } else {
 517                                 loop_bottom = new_label();
 518                                 val = show_expression(pre_condition);
 519                                 printf("\tje\t\tv%d, .L%d\n", val, loop_bottom);
 520                         }
 521                 }
 522                 if (!post_condition || post_condition->type != EXPR_VALUE || post_condition->value) {
 523                         loop_top = new_label();
 524                         printf(".L%d:\n", loop_top);
 525                 }
 526                 show_statement(statement);
 527                 if (stmt->iterator_continue->used)
 528                         printf(".L%p:\n", stmt->iterator_continue);
 529                 show_statement(post_statement);
 530                 if (!post_condition) {
 531                         printf("\tjmp\t\t.L%d\n", loop_top);
 532                 } else if (post_condition->type == EXPR_VALUE) {
 533                         if (post_condition->value)
 534                                 printf("\tjmp\t\t.L%d\n", loop_top);
 535                 } else {
 536                         val = show_expression(post_condition);
 537                         printf("\tjne\t\tv%d, .L%d\n", val, loop_top);
 538                 }
 539                 if (stmt->iterator_break->used)
 540                         printf(".L%p:\n", stmt->iterator_break);
 541                 if (loop_bottom)
 542                         printf(".L%d:\n", loop_bottom);
 543                 break;
 544         }
 545         case STMT_NONE:
 546                 break;
 547
 548         case STMT_LABEL:
 549                 printf(".L%p:\n", stmt->label_identifier);
 550                 show_statement(stmt->label_statement);
 551                 break;
 552
 553         case STMT_GOTO:
 554                 if (stmt->goto_expression) {
 555                         int val = show_expression(stmt->goto_expression);
 556                         printf("\tgoto\t\t*v%d\n", val);
 557                 } else {
 558                         printf("\tgoto\t\t.L%p\n", stmt->goto_label->bb_target);
 559                 }
 560                 break;
 561         case STMT_ASM:
 562                 printf("\tasm( .... )\n");
 563                 break;
 564         case STMT_INTERNAL: {
 565                 int val = show_expression(stmt->expression);
 566                 printf("\tINTERNAL( %d )\n", val);
 567                 break;
 568         }
 569         }
 570         return 0;
 571 }
 572
 573 static int show_call_expression(struct expression *expr)
 574 {
 575         struct symbol *direct;
 576         struct expression *arg, *fn;
 577         int fncall, retval;
 578         int framesize;
 579
 580         if (!expr->ctype) {
 581                 warning(expr->pos, "\tcall with no type!");
 582                 return 0;
 583         }
 584
 585         framesize = 0;
 586         FOR_EACH_PTR_REVERSE(expr->args, arg) {
 587                 int new = show_expression(arg);
 588                 int size = arg->ctype->bit_size;
 589                 printf("\tpush.%d\t\tv%d\n", size, new);
 590                 framesize += size >> 3;
 591         } END_FOR_EACH_PTR_REVERSE(arg);
 592
 593         fn = expr->fn;
 594
 595         /* Remove dereference, if any */
 596         direct = NULL;
 597         if (fn->type == EXPR_PREOP) {
 598                 if (fn->unop->type == EXPR_SYMBOL) {
 599                         struct symbol *sym = fn->unop->symbol;
 600                         if (sym->ctype.base_type->type == SYM_FN)
 601                                 direct = sym;
 602                 }
 603         }
 604         if (direct) {
 605                 printf("\tcall\t\t%s\n", show_ident(direct->ident));
 606         } else {
 607                 fncall = show_expression(fn);
 608                 printf("\tcall\t\t*v%d\n", fncall);
 609         }
 610         if (framesize)
 611                 printf("\tadd.%d\t\tvSP,vSP,$%d\n", bits_in_pointer, framesize);
 612
 613         retval = new_pseudo();
 614         printf("\tmov.%d\t\tv%d,retval\n", expr->ctype->bit_size, retval);
 615         return retval;
 616 }
 617
 618 static int show_binop(struct expression *expr)
 619 {
 620         int left = show_expression(expr->left);
 621         int right = show_expression(expr->right);
 622         int new = new_pseudo();
 623         const char *opname;
 624         static const char *name[] = {
 625                 ['+'] = "add", ['-'] = "sub",
 626                 ['*'] = "mul", ['/'] = "div",
 627                 ['%'] = "mod", ['&'] = "and",
 628                 ['|'] = "lor", ['^'] = "xor"
 629         };
 630         unsigned int op = expr->op;
 631
 632         opname = show_special(op);
 633         if (op < sizeof(name)/sizeof(*name))
 634                 opname = name[op];
 635         printf("\t%s.%d\t\tv%d,v%d,v%d\n", opname,
 636                 expr->ctype->bit_size,
 637                 new, left, right);
 638         return new;
 639 }
 640
 641 static int show_slice(struct expression *expr)
 642 {
 643         int target = show_expression(expr->base);
 644         int new = new_pseudo();
 645         printf("\tslice.%d\t\tv%d,v%d,%d\n", expr->r_nrbits, target, new, expr->r_bitpos);
 646         return new;
 647 }
 648
 649 static int show_regular_preop(struct expression *expr)
 650 {
 651         int target = show_expression(expr->unop);
 652         int new = new_pseudo();
 653         static const char *name[] = {
 654                 ['!'] = "nonzero", ['-'] = "neg",
 655                 ['~'] = "not",
 656         };
 657         unsigned int op = expr->op;
 658         const char *opname;
 659
 660         opname = show_special(op);
 661         if (op < sizeof(name)/sizeof(*name))
 662                 opname = name[op];
 663         printf("\t%s.%d\t\tv%d,v%d\n", opname, expr->ctype->bit_size, new, target);
 664         return new;
 665 }
 666
 667 /*
 668  * FIXME! Not all accesses are memory loads. We should
 669  * check what kind of symbol is behind the dereference.
 670  */
 671 static int show_address_gen(struct expression *expr)
 672 {
 673         return show_expression(expr->unop);
 674 }
 675
 676 static int show_load_gen(int bits, struct expression *expr, int addr)
 677 {
 678         int new = new_pseudo();
 679
 680         printf("\tld.%d\t\tv%d,[v%d]\n", bits, new, addr);
 681         return new;
 682 }
 683
 684 static void show_store_gen(int bits, int value, struct expression *expr, int addr)
 685 {
 686         /* FIXME!!! Bitfield store! */
 687         printf("\tst.%d\t\tv%d,[v%d]\n", bits, value, addr);
 688 }
 689
 690 static int show_assignment(struct expression *expr)
 691 {
 692         struct expression *target = expr->left;
 693         int val, addr, bits;
 694
 695         if (!expr->ctype)
 696                 return 0;
 697
 698         bits = expr->ctype->bit_size;
 699         val = show_expression(expr->right);
 700         addr = show_address_gen(target);
 701         show_store_gen(bits, val, target, addr);
 702         return val;
 703 }
 704
 705 static int show_return_stmt(struct statement *stmt)
 706 {
 707         struct expression *expr = stmt->ret_value;
 708         struct symbol *target = stmt->ret_target;
 709
 710         if (expr && expr->ctype) {
 711                 int val = show_expression(expr);
 712                 int bits = expr->ctype->bit_size;
 713                 int addr = show_symbol_expr(target);
 714                 show_store_gen(bits, val, NULL, addr);
 715         }
 716         printf("\tret\t\t(%p)\n", target);
 717         return 0;
 718 }
 719
 720 static int show_initialization(struct symbol *sym, struct expression *expr)
 721 {
 722         int val, addr, bits;
 723
 724         if (!expr->ctype)
 725                 return 0;
 726
 727         bits = expr->ctype->bit_size;
 728         val = show_expression(expr);
 729         addr = show_symbol_expr(sym);
 730         // FIXME! The "target" expression is for bitfield store information.
 731         // Leave it NULL, which works fine.
 732         show_store_gen(bits, val, NULL, addr);
 733         return 0;
 734 }
 735
 736 static int show_access(struct expression *expr)
 737 {
 738         int addr = show_address_gen(expr);
 739         return show_load_gen(expr->ctype->bit_size, expr, addr);
 740 }
 741
 742 static int show_inc_dec(struct expression *expr, int postop)
 743 {
 744         int addr = show_address_gen(expr->unop);
 745         int retval, new;
 746         const char *opname = expr->op == SPECIAL_INCREMENT ? "add" : "sub";
 747         int bits = expr->ctype->bit_size;
 748
 749         retval = show_load_gen(bits, expr->unop, addr);
 750         new = retval;
 751         if (postop)
 752                 new = new_pseudo();
 753         printf("\t%s.%d\t\tv%d,v%d,$1\n", opname, bits, new, retval);
 754         show_store_gen(bits, new, expr->unop, addr);
 755         return retval;
 756 }
 757
 758 static int show_preop(struct expression *expr)
 759 {
 760         /*
 761          * '*' is an lvalue access, and is fundamentally different
 762          * from an arithmetic operation. Maybe it should have an
 763          * expression type of its own..
 764          */
 765         if (expr->op == '*')
 766                 return show_access(expr);
 767         if (expr->op == SPECIAL_INCREMENT || expr->op == SPECIAL_DECREMENT)
 768                 return show_inc_dec(expr, 0);
 769         return show_regular_preop(expr);
 770 }
 771
 772 static int show_postop(struct expression *expr)
 773 {
 774         return show_inc_dec(expr, 1);
 775 }
 776
 777 static int show_symbol_expr(struct symbol *sym)
 778 {
 779         int new = new_pseudo();
 780
 781         if (sym->initializer && sym->initializer->type == EXPR_STRING)
 782                 return show_string_expr(sym->initializer);
 783
 784         if (sym->ctype.modifiers & (MOD_TOPLEVEL | MOD_EXTERN | MOD_STATIC)) {
 785                 printf("\tmovi.%d\t\tv%d,$%s\n", bits_in_pointer, new, show_ident(sym->ident));
 786                 return new;
 787         }
 788         if (sym->ctype.modifiers & MOD_ADDRESSABLE) {
 789                 printf("\taddi.%d\t\tv%d,vFP,$%lld\n", bits_in_pointer, new, sym->value);
 790                 return new;
 791         }
 792         printf("\taddi.%d\t\tv%d,vFP,$offsetof(%s:%p)\n", bits_in_pointer, new, show_ident(sym->ident), sym);
 793         return new;
 794 }
 795
 796 static int show_symbol_init(struct symbol *sym)
 797 {
 798         struct expression *expr = sym->initializer;
 799
 800         if (expr) {
 801                 int val, addr, bits;
 802
 803                 bits = expr->ctype->bit_size;
 804                 val = show_expression(expr);
 805                 addr = show_symbol_expr(sym);
 806                 show_store_gen(bits, val, NULL, addr);
 807         }
 808         return 0;
 809 }
 810
 811 static int type_is_signed(struct symbol *sym)
 812 {
 813         if (sym->type == SYM_NODE)
 814                 sym = sym->ctype.base_type;
 815         if (sym->type == SYM_PTR)
 816                 return 0;
 817         return !(sym->ctype.modifiers & MOD_UNSIGNED);
 818 }
 819
 820 static int show_cast_expr(struct expression *expr)
 821 {
 822         struct symbol *old_type, *new_type;
 823         int op = show_expression(expr->cast_expression);
 824         int oldbits, newbits;
 825         int new, is_signed;
 826
 827         old_type = expr->cast_expression->ctype;
 828         new_type = expr->cast_type;
 829
 830         oldbits = old_type->bit_size;
 831         newbits = new_type->bit_size;
 832         if (oldbits >= newbits)
 833                 return op;
 834         new = new_pseudo();
 835         is_signed = type_is_signed(old_type);
 836         if (is_signed) {
 837                 printf("\tsext%d.%d\tv%d,v%d\n", oldbits, newbits, new, op);
 838         } else {
 839                 printf("\tandl.%d\t\tv%d,v%d,$%lu\n", newbits, new, op, (1UL << oldbits)-1);
 840         }
 841         return new;
 842 }
 843
 844 static int show_value(struct expression *expr)
 845 {
 846         int new = new_pseudo();
 847         unsigned long long value = expr->value;
 848
 849         printf("\tmovi.%d\t\tv%d,$%llu\n", expr->ctype->bit_size, new, value);
 850         return new;
 851 }
 852
 853 static int show_fvalue(struct expression *expr)
 854 {
 855         int new = new_pseudo();
 856         long double value = expr->fvalue;
 857
 858         printf("\tmovf.%d\t\tv%d,$%Lf\n", expr->ctype->bit_size, new, value);
 859         return new;
 860 }
 861
 862 static int show_string_expr(struct expression *expr)
 863 {
 864         int new = new_pseudo();
 865
 866         printf("\tmovi.%d\t\tv%d,&%s\n", bits_in_pointer, new, show_string(expr->string));
 867         return new;
 868 }
 869
 870 int show_label_expr(struct expression *expr)
 871 {
 872         int new = new_pseudo();
 873         printf("\tmovi.%d\t\tv%d,.L%p\n",bits_in_pointer, new, expr->label_symbol);
 874         return new;
 875 }
 876
 877 static int show_conditional_expr(struct expression *expr)
 878 {
 879         int cond = show_expression(expr->conditional);
 880         int true = show_expression(expr->cond_true);
 881         int false = show_expression(expr->cond_false);
 882         int new = new_pseudo();
 883
 884         printf("[v%d]\tcmov.%d\t\tv%d,v%d,v%d\n", cond, expr->ctype->bit_size, new, true, false);
 885         return new;
 886 }
 887
 888 static int show_statement_expr(struct expression *expr)
 889 {
 890         return show_statement(expr->statement);
 891 }
 892
 893 static int show_position_expr(struct expression *expr, struct symbol *base)
 894 {
 895         int new = show_expression(expr->init_expr);
 896         struct symbol *ctype = expr->init_expr->ctype;
 897         int bit_offset;
 898
 899         bit_offset = ctype ? ctype->bit_offset : -1;
 900
 901         printf("\tinsert v%d at [%d:%d] of %s\n", new,
 902                 expr->init_offset, bit_offset,
 903                 show_ident(base->ident));
 904         return 0;
 905 }
 906
 907 static int show_initializer_expr(struct expression *expr, struct symbol *ctype)
 908 {
 909         struct expression *entry;
 910
 911         FOR_EACH_PTR(expr->expr_list, entry) {
 912
 913 again:
 914                 // Nested initializers have their positions already
 915                 // recursively calculated - just output them too
 916                 if (entry->type == EXPR_INITIALIZER) {
 917                         show_initializer_expr(entry, ctype);
 918                         continue;
 919                 }
 920
 921                 // Initializer indexes and identifiers should
 922                 // have been evaluated to EXPR_POS
 923                 if (entry->type == EXPR_IDENTIFIER) {
 924                         printf(" AT '%s':\n", show_ident(entry->expr_ident));
 925                         entry = entry->ident_expression;
 926                         goto again;
 927                 }
 928
 929                 if (entry->type == EXPR_INDEX) {
 930                         printf(" AT '%d..%d:\n", entry->idx_from, entry->idx_to);
 931                         entry = entry->idx_expression;
 932                         goto again;
 933                 }
 934                 if (entry->type == EXPR_POS) {
 935                         show_position_expr(entry, ctype);
 936                         continue;
 937                 }
 938                 show_initialization(ctype, entry);
 939         } END_FOR_EACH_PTR(entry);
 940         return 0;
 941 }
 942
 943 int show_symbol_expr_init(struct symbol *sym)
 944 {
 945         struct expression *expr = sym->initializer;
 946
 947         if (expr)
 948                 show_expression(expr);
 949         return show_symbol_expr(sym);
 950 }
 951
 952 /*
 953  * Print out an expression. Return the pseudo that contains the
 954  * variable.
 955  */
 956 int show_expression(struct expression *expr)
 957 {
 958         if (!expr)
 959                 return 0;
 960
 961         if (!expr->ctype) {
 962                 struct position *pos = &expr->pos;
 963                 printf("\tno type at %s:%d:%d\n",
 964                         stream_name(pos->stream),
 965                         pos->line, pos->pos);
 966                 return 0;
 967         }
 968
 969         switch (expr->type) {
 970         case EXPR_CALL:
 971                 return show_call_expression(expr);
 972
 973         case EXPR_ASSIGNMENT:
 974                 return show_assignment(expr);
 975
 976         case EXPR_BINOP:
 977         case EXPR_COMMA:
 978         case EXPR_COMPARE:
 979         case EXPR_LOGICAL:
 980                 return show_binop(expr);
 981         case EXPR_PREOP:
 982                 return show_preop(expr);
 983         case EXPR_POSTOP:
 984                 return show_postop(expr);
 985         case EXPR_SYMBOL:
 986                 return show_symbol_expr(expr->symbol);
 987         case EXPR_DEREF:
 988         case EXPR_SIZEOF:
 989         case EXPR_PTRSIZEOF:
 990         case EXPR_ALIGNOF:
 991                 warning(expr->pos, "invalid expression after evaluation");
 992                 return 0;
 993         case EXPR_CAST:
 994         case EXPR_IMPLIED_CAST:
 995                 return show_cast_expr(expr);
 996         case EXPR_VALUE:
 997                 return show_value(expr);
 998         case EXPR_FVALUE:
 999                 return show_fvalue(expr);
1000         case EXPR_STRING:
1001                 return show_string_expr(expr);
1002         case EXPR_INITIALIZER:
1003                 return show_initializer_expr(expr, expr->ctype);
1004         case EXPR_SELECT:
1005         case EXPR_CONDITIONAL:
1006                 return show_conditional_expr(expr);
1007         case EXPR_STATEMENT:
1008                 return show_statement_expr(expr);
1009         case EXPR_LABEL:
1010                 return show_label_expr(expr);
1011         case EXPR_SLICE:
1012                 return show_slice(expr);
1013
1014         // None of these should exist as direct expressions: they are only
1015         // valid as sub-expressions of initializers.
1016         case EXPR_POS:
1017                 warning(expr->pos, "unable to show plain initializer position expression");
1018                 return 0;
1019         case EXPR_IDENTIFIER:
1020                 warning(expr->pos, "unable to show identifier expression");
1021                 return 0;
1022         case EXPR_INDEX:
1023                 warning(expr->pos, "unable to show index expression");
1024                 return 0;
1025         case EXPR_TYPE:
1026                 warning(expr->pos, "unable to show type expression");
1027                 return 0;
1028         }
1029         return 0;
1030 }