show-parse.c

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