1 /*
   2  * Example usage:
   3  *      ./sparse-llvm hello.c | llc | as -o hello.o
   4  */
   5 
   6 #include <llvm-c/Core.h>
   7 #include <llvm-c/BitWriter.h>
   8 #include <llvm-c/Analysis.h>
   9 #include <llvm-c/Target.h>
  10 
  11 #include <stdbool.h>
  12 #include <stdio.h>
  13 #include <unistd.h>
  14 #include <string.h>
  15 #include <assert.h>
  16 
  17 #include "symbol.h"
  18 #include "expression.h"
  19 #include "linearize.h"
  20 #include "flow.h"
  21 
  22 struct function {
  23         LLVMBuilderRef                  builder;
  24         LLVMTypeRef                     type;
  25         LLVMValueRef                    fn;
  26         LLVMModuleRef                   module;
  27 };
  28 
  29 static inline bool symbol_is_fp_type(struct symbol *sym)
  30 {
  31         if (!sym)
  32                 return false;
  33 
  34         return sym->ctype.base_type == &fp_type;
  35 }
  36 
  37 static LLVMTypeRef symbol_type(LLVMModuleRef module, struct symbol *sym);
  38 
  39 static LLVMTypeRef func_return_type(LLVMModuleRef module, struct symbol *sym)
  40 {
  41         return symbol_type(module, sym->ctype.base_type);
  42 }
  43 
  44 static LLVMTypeRef sym_func_type(LLVMModuleRef module, struct symbol *sym)
  45 {
  46         LLVMTypeRef *arg_type;
  47         LLVMTypeRef func_type;
  48         LLVMTypeRef ret_type;
  49         struct symbol *arg;
  50         int n_arg = 0;
  51 
  52         /* to avoid strangeness with varargs [for now], we build
  53          * the function and type anew, for each call.  This
  54          * is probably wrong.  We should look up the
  55          * symbol declaration info.
  56          */
  57 
  58         ret_type = func_return_type(module, sym);
  59 
  60         /* count args, build argument type information */
  61         FOR_EACH_PTR(sym->arguments, arg) {
  62                 n_arg++;
  63         } END_FOR_EACH_PTR(arg);
  64 
  65         arg_type = calloc(n_arg, sizeof(LLVMTypeRef));
  66 
  67         int idx = 0;
  68         FOR_EACH_PTR(sym->arguments, arg) {
  69                 struct symbol *arg_sym = arg->ctype.base_type;
  70 
  71                 arg_type[idx++] = symbol_type(module, arg_sym);
  72         } END_FOR_EACH_PTR(arg);
  73         func_type = LLVMFunctionType(ret_type, arg_type, n_arg,
  74                                      sym->variadic);
  75 
  76         return func_type;
  77 }
  78 
  79 static LLVMTypeRef sym_array_type(LLVMModuleRef module, struct symbol *sym)
  80 {
  81         LLVMTypeRef elem_type;
  82         struct symbol *base_type;
  83 
  84         base_type = sym->ctype.base_type;
  85         /* empty struct is undefined [6.7.2.1(8)] */
  86         assert(base_type->bit_size > 0);
  87 
  88         elem_type = symbol_type(module, base_type);
  89         if (!elem_type)
  90                 return NULL;
  91 
  92         return LLVMArrayType(elem_type, sym->bit_size / base_type->bit_size);
  93 }
  94 
  95 #define MAX_STRUCT_MEMBERS 64
  96 
  97 static LLVMTypeRef sym_struct_type(LLVMModuleRef module, struct symbol *sym)
  98 {
  99         LLVMTypeRef elem_types[MAX_STRUCT_MEMBERS];
 100         struct symbol *member;
 101         char buffer[256];
 102         LLVMTypeRef ret;
 103         unsigned nr = 0;
 104 
 105         snprintf(buffer, sizeof(buffer), "struct.%s", sym->ident ? sym->ident->name : "anno");
 106         ret = LLVMStructCreateNamed(LLVMGetGlobalContext(), buffer);
 107         /* set ->aux to avoid recursion */
 108         sym->aux = ret;
 109 
 110         FOR_EACH_PTR(sym->symbol_list, member) {
 111                 LLVMTypeRef member_type;
 112 
 113                 assert(nr < MAX_STRUCT_MEMBERS);
 114 
 115                 member_type = symbol_type(module, member);
 116 
 117                 elem_types[nr++] = member_type; 
 118         } END_FOR_EACH_PTR(member);
 119 
 120         LLVMStructSetBody(ret, elem_types, nr, 0 /* packed? */); 
 121         return ret;
 122 }
 123 
 124 static LLVMTypeRef sym_union_type(LLVMModuleRef module, struct symbol *sym)
 125 {
 126         LLVMTypeRef elements;
 127         unsigned union_size;
 128 
 129         /*
 130          * There's no union support in the LLVM API so we treat unions as
 131          * opaque structs. The downside is that we lose type information on the
 132          * members but as LLVM doesn't care, neither do we.
 133          */
 134         union_size = sym->bit_size / 8;
 135 
 136         elements = LLVMArrayType(LLVMInt8Type(), union_size);
 137 
 138         return LLVMStructType(&elements, 1, 0 /* packed? */);
 139 }
 140 
 141 static LLVMTypeRef sym_ptr_type(LLVMModuleRef module, struct symbol *sym)
 142 {
 143         LLVMTypeRef type;
 144 
 145         /* 'void *' is treated like 'char *' */
 146         if (is_void_type(sym->ctype.base_type))
 147                 type = LLVMInt8Type();
 148         else
 149                 type = symbol_type(module, sym->ctype.base_type);
 150 
 151         return LLVMPointerType(type, 0);
 152 }
 153 
 154 static LLVMTypeRef sym_basetype_type(struct symbol *sym)
 155 {
 156         LLVMTypeRef ret = NULL;
 157 
 158         if (symbol_is_fp_type(sym)) {
 159                 switch (sym->bit_size) {
 160                 case 32:
 161                         ret = LLVMFloatType();
 162                         break;
 163                 case 64:
 164                         ret = LLVMDoubleType();
 165                         break;
 166                 case 80:
 167                         ret = LLVMX86FP80Type();
 168                         break;
 169                 default:
 170                         die("invalid bit size %d for type %d", sym->bit_size, sym->type);
 171                         break;
 172                 }
 173         } else {
 174                 switch (sym->bit_size) {
 175                 case -1:
 176                         ret = LLVMVoidType();
 177                         break;
 178                 case 1:
 179                         ret = LLVMInt1Type();
 180                         break;
 181                 case 8:
 182                         ret = LLVMInt8Type();
 183                         break;
 184                 case 16:
 185                         ret = LLVMInt16Type();
 186                         break;
 187                 case 32:
 188                         ret = LLVMInt32Type();
 189                         break;
 190                 case 64:
 191                         ret = LLVMInt64Type();
 192                         break;
 193                 default:
 194                         die("invalid bit size %d for type %d", sym->bit_size, sym->type);
 195                         break;
 196                 }
 197         }
 198 
 199         return ret;
 200 }
 201 
 202 static LLVMTypeRef symbol_type(LLVMModuleRef module, struct symbol *sym)
 203 {
 204         LLVMTypeRef ret = NULL;
 205 
 206         /* don't cache the result for SYM_NODE */
 207         if (sym->type == SYM_NODE)
 208                 return symbol_type(module, sym->ctype.base_type);
 209 
 210         if (sym->aux)
 211                 return sym->aux;
 212 
 213         switch (sym->type) {
 214         case SYM_BITFIELD:
 215         case SYM_ENUM:
 216                 ret = symbol_type(module, sym->ctype.base_type);
 217                 break;
 218         case SYM_BASETYPE:
 219                 ret = sym_basetype_type(sym);
 220                 break;
 221         case SYM_PTR:
 222                 ret = sym_ptr_type(module, sym);
 223                 break;
 224         case SYM_UNION:
 225                 ret = sym_union_type(module, sym);
 226                 break;
 227         case SYM_STRUCT:
 228                 ret = sym_struct_type(module, sym);
 229                 break;
 230         case SYM_ARRAY:
 231                 ret = sym_array_type(module, sym);
 232                 break;
 233         case SYM_FN:
 234                 ret = sym_func_type(module, sym);
 235                 break;
 236         default:
 237                 assert(0);
 238         }
 239 
 240         /* cache the result */
 241         sym->aux = ret;
 242         return ret;
 243 }
 244 
 245 static LLVMTypeRef int_type_by_size(int size)
 246 {
 247         switch (size) {
 248                 case 1:         return LLVMInt1Type();
 249                 case 8:         return LLVMInt8Type();
 250                 case 16:        return LLVMInt16Type();
 251                 case 32:        return LLVMInt32Type();
 252                 case 64:        return LLVMInt64Type();
 253 
 254                 default:
 255                         die("invalid bit size %d", size);
 256                         break;
 257         }
 258         return NULL;    /* not reached */
 259 }
 260 
 261 static LLVMTypeRef insn_symbol_type(LLVMModuleRef module, struct instruction *insn)
 262 {
 263         if (insn->type)
 264                 return symbol_type(module, insn->type);
 265 
 266         return int_type_by_size(insn->size);
 267 }
 268 
 269 static LLVMLinkage data_linkage(struct symbol *sym)
 270 {
 271         if (sym->ctype.modifiers & MOD_STATIC)
 272                 return LLVMPrivateLinkage;
 273 
 274         return LLVMExternalLinkage;
 275 }
 276 
 277 static LLVMLinkage function_linkage(struct symbol *sym)
 278 {
 279         if (sym->ctype.modifiers & MOD_STATIC)
 280                 return LLVMInternalLinkage;
 281 
 282         return LLVMExternalLinkage;
 283 }
 284 
 285 #define MAX_PSEUDO_NAME 64
 286 
 287 static void pseudo_name(pseudo_t pseudo, char *buf)
 288 {
 289         switch (pseudo->type) {
 290         case PSEUDO_REG:
 291                 snprintf(buf, MAX_PSEUDO_NAME, "R%d", pseudo->nr);
 292                 break;
 293         case PSEUDO_SYM:
 294                 assert(0);
 295                 break;
 296         case PSEUDO_VAL:
 297                 assert(0);
 298                 break;
 299         case PSEUDO_ARG: {
 300                 assert(0);
 301                 break;
 302         }
 303         case PSEUDO_PHI:
 304                 snprintf(buf, MAX_PSEUDO_NAME, "PHI%d", pseudo->nr);
 305                 break;
 306         default:
 307                 assert(0);
 308         }
 309 }
 310 
 311 static LLVMValueRef pseudo_to_value(struct function *fn, struct instruction *insn, pseudo_t pseudo)
 312 {
 313         LLVMValueRef result = NULL;
 314 
 315         switch (pseudo->type) {
 316         case PSEUDO_REG:
 317                 result = pseudo->priv;
 318                 break;
 319         case PSEUDO_SYM: {
 320                 struct symbol *sym = pseudo->sym;
 321                 struct expression *expr;
 322 
 323                 assert(sym->bb_target == NULL);
 324 
 325                 expr = sym->initializer;
 326                 if (expr) {
 327                         switch (expr->type) {
 328                         case EXPR_STRING: {
 329                                 const char *s = expr->string->data;
 330                                 LLVMValueRef indices[] = { LLVMConstInt(LLVMInt64Type(), 0, 0), LLVMConstInt(LLVMInt64Type(), 0, 0) };
 331                                 LLVMValueRef data;
 332 
 333                                 data = LLVMAddGlobal(fn->module, LLVMArrayType(LLVMInt8Type(), strlen(s) + 1), ".str");
 334                                 LLVMSetLinkage(data, LLVMPrivateLinkage);
 335                                 LLVMSetGlobalConstant(data, 1);
 336                                 LLVMSetInitializer(data, LLVMConstString(strdup(s), strlen(s) + 1, true));
 337 
 338                                 result = LLVMConstGEP(data, indices, ARRAY_SIZE(indices));
 339                                 break;
 340                         }
 341                         case EXPR_SYMBOL: {
 342                                 struct symbol *sym = expr->symbol;
 343 
 344                                 result = LLVMGetNamedGlobal(fn->module, show_ident(sym->ident));
 345                                 assert(result != NULL);
 346                                 break;
 347                         }
 348                         default:
 349                                 assert(0);
 350                         }
 351                 } else {
 352                         const char *name = show_ident(sym->ident);
 353                         LLVMTypeRef type = symbol_type(fn->module, sym);
 354 
 355                         if (LLVMGetTypeKind(type) == LLVMFunctionTypeKind) {
 356                                 result = LLVMGetNamedFunction(fn->module, name);
 357                                 if (!result)
 358                                         result = LLVMAddFunction(fn->module, name, type);
 359                         } else {
 360                                 result = LLVMGetNamedGlobal(fn->module, name);
 361                                 if (!result)
 362                                         result = LLVMAddGlobal(fn->module, type, name);
 363                         }
 364                 }
 365                 break;
 366         }
 367         case PSEUDO_VAL:
 368                 result = LLVMConstInt(int_type_by_size(pseudo->size), pseudo->value, 1);
 369                 break;
 370         case PSEUDO_ARG: {
 371                 result = LLVMGetParam(fn->fn, pseudo->nr - 1);
 372                 break;
 373         }
 374         case PSEUDO_PHI:
 375                 result = pseudo->priv;
 376                 break;
 377         case PSEUDO_VOID:
 378                 result = NULL;
 379                 break;
 380         default:
 381                 assert(0);
 382         }
 383 
 384         return result;
 385 }
 386 
 387 static LLVMValueRef calc_gep(LLVMBuilderRef builder, LLVMValueRef base, LLVMValueRef off)
 388 {
 389         LLVMTypeRef type = LLVMTypeOf(base);
 390         unsigned int as = LLVMGetPointerAddressSpace(type);
 391         LLVMTypeRef bytep = LLVMPointerType(LLVMInt8Type(), as);
 392         LLVMValueRef addr;
 393 
 394         /* convert base to char* type */
 395         base = LLVMBuildPointerCast(builder, base, bytep, "");
 396         /* addr = base + off */
 397         addr = LLVMBuildInBoundsGEP(builder, base, &off, 1, "");
 398         /* convert back to the actual pointer type */
 399         addr = LLVMBuildPointerCast(builder, addr, type, "");
 400         return addr;
 401 }
 402 
 403 static LLVMRealPredicate translate_fop(int opcode)
 404 {
 405         static const LLVMRealPredicate trans_tbl[] = {
 406                 [OP_SET_EQ]     = LLVMRealOEQ,
 407                 [OP_SET_NE]     = LLVMRealUNE,
 408                 [OP_SET_LE]     = LLVMRealOLE,
 409                 [OP_SET_GE]     = LLVMRealOGE,
 410                 [OP_SET_LT]     = LLVMRealOLT,
 411                 [OP_SET_GT]     = LLVMRealOGT,
 412                 /* Are these used with FP? */
 413                 [OP_SET_B]      = LLVMRealOLT,
 414                 [OP_SET_A]      = LLVMRealOGT,
 415                 [OP_SET_BE]     = LLVMRealOLE,
 416                 [OP_SET_AE]     = LLVMRealOGE,
 417         };
 418 
 419         return trans_tbl[opcode];
 420 }
 421 
 422 static LLVMIntPredicate translate_op(int opcode)
 423 {
 424         static const LLVMIntPredicate trans_tbl[] = {
 425                 [OP_SET_EQ]     = LLVMIntEQ,
 426                 [OP_SET_NE]     = LLVMIntNE,
 427                 [OP_SET_LE]     = LLVMIntSLE,
 428                 [OP_SET_GE]     = LLVMIntSGE,
 429                 [OP_SET_LT]     = LLVMIntSLT,
 430                 [OP_SET_GT]     = LLVMIntSGT,
 431                 [OP_SET_B]      = LLVMIntULT,
 432                 [OP_SET_A]      = LLVMIntUGT,
 433                 [OP_SET_BE]     = LLVMIntULE,
 434                 [OP_SET_AE]     = LLVMIntUGE,
 435         };
 436 
 437         return trans_tbl[opcode];
 438 }
 439 
 440 static void output_op_binary(struct function *fn, struct instruction *insn)
 441 {
 442         LLVMValueRef lhs, rhs, target;
 443         char target_name[64];
 444 
 445         lhs = pseudo_to_value(fn, insn, insn->src1);
 446 
 447         rhs = pseudo_to_value(fn, insn, insn->src2);
 448 
 449         pseudo_name(insn->target, target_name);
 450 
 451         switch (insn->opcode) {
 452         /* Binary */
 453         case OP_ADD:
 454                 if (symbol_is_fp_type(insn->type))
 455                         target = LLVMBuildFAdd(fn->builder, lhs, rhs, target_name);
 456                 else
 457                         target = LLVMBuildAdd(fn->builder, lhs, rhs, target_name);
 458                 break;
 459         case OP_SUB:
 460                 if (symbol_is_fp_type(insn->type))
 461                         target = LLVMBuildFSub(fn->builder, lhs, rhs, target_name);
 462                 else
 463                         target = LLVMBuildSub(fn->builder, lhs, rhs, target_name);
 464                 break;
 465         case OP_MULU:
 466                 if (symbol_is_fp_type(insn->type))
 467                         target = LLVMBuildFMul(fn->builder, lhs, rhs, target_name);
 468                 else
 469                         target = LLVMBuildMul(fn->builder, lhs, rhs, target_name);
 470                 break;
 471         case OP_MULS:
 472                 assert(!symbol_is_fp_type(insn->type));
 473                 target = LLVMBuildMul(fn->builder, lhs, rhs, target_name);
 474                 break;
 475         case OP_DIVU:
 476                 if (symbol_is_fp_type(insn->type))
 477                         target = LLVMBuildFDiv(fn->builder, lhs, rhs, target_name);
 478                 else
 479                         target = LLVMBuildUDiv(fn->builder, lhs, rhs, target_name);
 480                 break;
 481         case OP_DIVS:
 482                 assert(!symbol_is_fp_type(insn->type));
 483                 target = LLVMBuildSDiv(fn->builder, lhs, rhs, target_name);
 484                 break;
 485         case OP_MODU:
 486                 assert(!symbol_is_fp_type(insn->type));
 487                 target = LLVMBuildURem(fn->builder, lhs, rhs, target_name);
 488                 break;
 489         case OP_MODS:
 490                 assert(!symbol_is_fp_type(insn->type));
 491                 target = LLVMBuildSRem(fn->builder, lhs, rhs, target_name);
 492                 break;
 493         case OP_SHL:
 494                 assert(!symbol_is_fp_type(insn->type));
 495                 target = LLVMBuildShl(fn->builder, lhs, rhs, target_name);
 496                 break;
 497         case OP_LSR:
 498                 assert(!symbol_is_fp_type(insn->type));
 499                 target = LLVMBuildLShr(fn->builder, lhs, rhs, target_name);
 500                 break;
 501         case OP_ASR:
 502                 assert(!symbol_is_fp_type(insn->type));
 503                 target = LLVMBuildAShr(fn->builder, lhs, rhs, target_name);
 504                 break;
 505         
 506         /* Logical */
 507         case OP_AND:
 508                 assert(!symbol_is_fp_type(insn->type));
 509                 target = LLVMBuildAnd(fn->builder, lhs, rhs, target_name);
 510                 break;
 511         case OP_OR:
 512                 assert(!symbol_is_fp_type(insn->type));
 513                 target = LLVMBuildOr(fn->builder, lhs, rhs, target_name);
 514                 break;
 515         case OP_XOR:
 516                 assert(!symbol_is_fp_type(insn->type));
 517                 target = LLVMBuildXor(fn->builder, lhs, rhs, target_name);
 518                 break;
 519         case OP_AND_BOOL: {
 520                 LLVMValueRef lhs_nz, rhs_nz;
 521                 LLVMTypeRef dst_type;
 522 
 523                 lhs_nz = LLVMBuildIsNotNull(fn->builder, lhs, "");
 524                 rhs_nz = LLVMBuildIsNotNull(fn->builder, rhs, "");
 525                 target = LLVMBuildAnd(fn->builder, lhs_nz, rhs_nz, target_name);
 526 
 527                 dst_type = insn_symbol_type(fn->module, insn);
 528                 target = LLVMBuildZExt(fn->builder, target, dst_type, target_name);
 529                 break;
 530         }
 531         case OP_OR_BOOL: {
 532                 LLVMValueRef lhs_nz, rhs_nz;
 533                 LLVMTypeRef dst_type;
 534 
 535                 lhs_nz = LLVMBuildIsNotNull(fn->builder, lhs, "");
 536                 rhs_nz = LLVMBuildIsNotNull(fn->builder, rhs, "");
 537                 target = LLVMBuildOr(fn->builder, lhs_nz, rhs_nz, target_name);
 538 
 539                 dst_type = insn_symbol_type(fn->module, insn);
 540                 target = LLVMBuildZExt(fn->builder, target, dst_type, target_name);
 541                 break;
 542         }
 543         default:
 544                 assert(0);
 545                 break;
 546         }
 547 
 548         insn->target->priv = target;
 549 }
 550 
 551 static void output_op_compare(struct function *fn, struct instruction *insn)
 552 {
 553         LLVMValueRef lhs, rhs, target;
 554         char target_name[64];
 555 
 556         lhs = pseudo_to_value(fn, insn, insn->src1);
 557 
 558         if (insn->src2->type == PSEUDO_VAL)
 559                 rhs = LLVMConstInt(LLVMTypeOf(lhs), insn->src2->value, 1);
 560         else
 561                 rhs = pseudo_to_value(fn, insn, insn->src2);
 562 
 563         pseudo_name(insn->target, target_name);
 564 
 565         LLVMTypeRef dst_type = insn_symbol_type(fn->module, insn);
 566 
 567         if (LLVMGetTypeKind(LLVMTypeOf(lhs)) == LLVMIntegerTypeKind) {
 568                 LLVMIntPredicate op = translate_op(insn->opcode);
 569 
 570                 target = LLVMBuildICmp(fn->builder, op, lhs, rhs, target_name);
 571         } else {
 572                 LLVMRealPredicate op = translate_fop(insn->opcode);
 573 
 574                 target = LLVMBuildFCmp(fn->builder, op, lhs, rhs, target_name);
 575         }
 576 
 577         target = LLVMBuildZExt(fn->builder, target, dst_type, target_name);
 578 
 579         insn->target->priv = target;
 580 }
 581 
 582 static void output_op_ret(struct function *fn, struct instruction *insn)
 583 {
 584         pseudo_t pseudo = insn->src;
 585 
 586         if (pseudo && pseudo != VOID) {
 587                 LLVMValueRef result = pseudo_to_value(fn, insn, pseudo);
 588 
 589                 LLVMBuildRet(fn->builder, result);
 590         } else
 591                 LLVMBuildRetVoid(fn->builder);
 592 }
 593 
 594 static LLVMValueRef calc_memop_addr(struct function *fn, struct instruction *insn)
 595 {
 596         LLVMTypeRef int_type, addr_type;
 597         LLVMValueRef src, off, addr;
 598         unsigned int as;
 599 
 600         /* int type large enough to hold a pointer */
 601         int_type = LLVMIntType(bits_in_pointer);
 602         off = LLVMConstInt(int_type, insn->offset, 0);
 603 
 604         /* convert src to the effective pointer type */
 605         src = pseudo_to_value(fn, insn, insn->src);
 606         as = LLVMGetPointerAddressSpace(LLVMTypeOf(src));
 607         addr_type = LLVMPointerType(insn_symbol_type(fn->module, insn), as);
 608         src = LLVMBuildPointerCast(fn->builder, src, addr_type, "");
 609 
 610         /* addr = src + off */
 611         addr = calc_gep(fn->builder, src, off);
 612         return addr;
 613 }
 614 
 615 
 616 static void output_op_load(struct function *fn, struct instruction *insn)
 617 {
 618         LLVMValueRef addr, target;
 619 
 620         addr = calc_memop_addr(fn, insn);
 621 
 622         /* perform load */
 623         target = LLVMBuildLoad(fn->builder, addr, "load_target");
 624 
 625         insn->target->priv = target;
 626 }
 627 
 628 static void output_op_store(struct function *fn, struct instruction *insn)
 629 {
 630         LLVMValueRef addr, target, target_in;
 631 
 632         addr = calc_memop_addr(fn, insn);
 633 
 634         target_in = pseudo_to_value(fn, insn, insn->target);
 635 
 636         /* perform store */
 637         target = LLVMBuildStore(fn->builder, target_in, addr);
 638 
 639         insn->target->priv = target;
 640 }
 641 
 642 static LLVMValueRef bool_value(struct function *fn, LLVMValueRef value)
 643 {
 644         if (LLVMTypeOf(value) != LLVMInt1Type())
 645                 value = LLVMBuildIsNotNull(fn->builder, value, "cond");
 646 
 647         return value;
 648 }
 649 
 650 static void output_op_cbr(struct function *fn, struct instruction *br)
 651 {
 652         LLVMValueRef cond = bool_value(fn,
 653                         pseudo_to_value(fn, br, br->cond));
 654 
 655         LLVMBuildCondBr(fn->builder, cond,
 656                         br->bb_true->priv,
 657                         br->bb_false->priv);
 658 }
 659 
 660 static void output_op_br(struct function *fn, struct instruction *br)
 661 {
 662         LLVMBuildBr(fn->builder, br->bb_true->priv);
 663 }
 664 
 665 static void output_op_sel(struct function *fn, struct instruction *insn)
 666 {
 667         LLVMValueRef target, src1, src2, src3;
 668 
 669         src1 = bool_value(fn, pseudo_to_value(fn, insn, insn->src1));
 670         src2 = pseudo_to_value(fn, insn, insn->src2);
 671         src3 = pseudo_to_value(fn, insn, insn->src3);
 672 
 673         target = LLVMBuildSelect(fn->builder, src1, src2, src3, "select");
 674 
 675         insn->target->priv = target;
 676 }
 677 
 678 static void output_op_switch(struct function *fn, struct instruction *insn)
 679 {
 680         LLVMValueRef sw_val, target;
 681         struct basic_block *def = NULL;
 682         struct multijmp *jmp;
 683         int n_jmp = 0;
 684 
 685         FOR_EACH_PTR(insn->multijmp_list, jmp) {
 686                 if (jmp->begin == jmp->end) {             /* case N */
 687                         n_jmp++;
 688                 } else if (jmp->begin < jmp->end) {    /* case M..N */
 689                         assert(0);
 690                 } else                                  /* default case */
 691                         def = jmp->target;
 692         } END_FOR_EACH_PTR(jmp);
 693 
 694         sw_val = pseudo_to_value(fn, insn, insn->target);
 695         target = LLVMBuildSwitch(fn->builder, sw_val,
 696                                  def ? def->priv : NULL, n_jmp);
 697 
 698         FOR_EACH_PTR(insn->multijmp_list, jmp) {
 699                 if (jmp->begin == jmp->end) {             /* case N */
 700                         LLVMAddCase(target,
 701                                 LLVMConstInt(LLVMInt32Type(), jmp->begin, 0),
 702                                 jmp->target->priv);
 703                 } else if (jmp->begin < jmp->end) {    /* case M..N */
 704                         assert(0);
 705                 }
 706         } END_FOR_EACH_PTR(jmp);
 707 
 708         insn->target->priv = target;
 709 }
 710 
 711 static void output_op_call(struct function *fn, struct instruction *insn)
 712 {
 713         LLVMValueRef target, func;
 714         int n_arg = 0, i;
 715         struct pseudo *arg;
 716         LLVMValueRef *args;
 717 
 718         FOR_EACH_PTR(insn->arguments, arg) {
 719                 n_arg++;
 720         } END_FOR_EACH_PTR(arg);
 721 
 722         args = calloc(n_arg, sizeof(LLVMValueRef));
 723 
 724         i = 0;
 725         FOR_EACH_PTR(insn->arguments, arg) {
 726                 args[i++] = pseudo_to_value(fn, insn, arg);
 727         } END_FOR_EACH_PTR(arg);
 728 
 729         func = pseudo_to_value(fn, insn, insn->func);
 730         target = LLVMBuildCall(fn->builder, func, args, n_arg, "");
 731 
 732         insn->target->priv = target;
 733 }
 734 
 735 static void output_op_phisrc(struct function *fn, struct instruction *insn)
 736 {
 737         LLVMValueRef v;
 738         struct instruction *phi;
 739 
 740         assert(insn->target->priv == NULL);
 741 
 742         /* target = src */
 743         v = pseudo_to_value(fn, insn, insn->phi_src);
 744 
 745         FOR_EACH_PTR(insn->phi_users, phi) {
 746                 LLVMValueRef load, ptr;
 747 
 748                 assert(phi->opcode == OP_PHI);
 749                 /* phi must be load from alloca */
 750                 load = phi->target->priv;
 751                 assert(LLVMGetInstructionOpcode(load) == LLVMLoad);
 752                 ptr = LLVMGetOperand(load, 0);
 753                 /* store v to alloca */
 754                 LLVMBuildStore(fn->builder, v, ptr);
 755         } END_FOR_EACH_PTR(phi);
 756 }
 757 
 758 static void output_op_phi(struct function *fn, struct instruction *insn)
 759 {
 760         LLVMValueRef load = insn->target->priv;
 761 
 762         /* forward load */
 763         assert(LLVMGetInstructionOpcode(load) == LLVMLoad);
 764         /* forward load has no parent block */
 765         assert(!LLVMGetInstructionParent(load));
 766         /* finalize load in current block  */
 767         LLVMInsertIntoBuilder(fn->builder, load);
 768 }
 769 
 770 static void output_op_ptrcast(struct function *fn, struct instruction *insn)
 771 {
 772         LLVMValueRef src, target;
 773         char target_name[64];
 774 
 775         src = insn->src->priv;
 776         if (!src)
 777                 src = pseudo_to_value(fn, insn, insn->src);
 778 
 779         pseudo_name(insn->target, target_name);
 780 
 781         assert(!symbol_is_fp_type(insn->type));
 782 
 783         target = LLVMBuildBitCast(fn->builder, src, insn_symbol_type(fn->module, insn), target_name);
 784 
 785         insn->target->priv = target;
 786 }
 787 
 788 static void output_op_cast(struct function *fn, struct instruction *insn, LLVMOpcode op)
 789 {
 790         LLVMValueRef src, target;
 791         char target_name[64];
 792 
 793         src = insn->src->priv;
 794         if (!src)
 795                 src = pseudo_to_value(fn, insn, insn->src);
 796 
 797         pseudo_name(insn->target, target_name);
 798 
 799         assert(!symbol_is_fp_type(insn->type));
 800 
 801         if (insn->size < LLVMGetIntTypeWidth(LLVMTypeOf(src)))
 802                 target = LLVMBuildTrunc(fn->builder, src, insn_symbol_type(fn->module, insn), target_name);
 803         else
 804                 target = LLVMBuildCast(fn->builder, op, src, insn_symbol_type(fn->module, insn), target_name);
 805 
 806         insn->target->priv = target;
 807 }
 808 
 809 static void output_insn(struct function *fn, struct instruction *insn)
 810 {
 811         switch (insn->opcode) {
 812         case OP_RET:
 813                 output_op_ret(fn, insn);
 814                 break;
 815         case OP_BR:
 816                 output_op_br(fn, insn);
 817                 break;
 818         case OP_CBR:
 819                 output_op_cbr(fn, insn);
 820                 break;
 821         case OP_SYMADDR:
 822                 assert(0);
 823                 break;
 824         case OP_SETVAL:
 825                 assert(0);
 826                 break;
 827         case OP_SWITCH:
 828                 output_op_switch(fn, insn);
 829                 break;
 830         case OP_COMPUTEDGOTO:
 831                 assert(0);
 832                 break;
 833         case OP_PHISOURCE:
 834                 output_op_phisrc(fn, insn);
 835                 break;
 836         case OP_PHI:
 837                 output_op_phi(fn, insn);
 838                 break;
 839         case OP_LOAD:
 840                 output_op_load(fn, insn);
 841                 break;
 842         case OP_LNOP:
 843                 assert(0);
 844                 break;
 845         case OP_STORE:
 846                 output_op_store(fn, insn);
 847                 break;
 848         case OP_SNOP:
 849                 assert(0);
 850                 break;
 851         case OP_INLINED_CALL:
 852                 assert(0);
 853                 break;
 854         case OP_CALL:
 855                 output_op_call(fn, insn);
 856                 break;
 857         case OP_CAST:
 858                 output_op_cast(fn, insn, LLVMZExt);
 859                 break;
 860         case OP_SCAST:
 861                 output_op_cast(fn, insn, LLVMSExt);
 862                 break;
 863         case OP_FPCAST:
 864                 assert(0);
 865                 break;
 866         case OP_PTRCAST:
 867                 output_op_ptrcast(fn, insn);
 868                 break;
 869         case OP_BINARY ... OP_BINARY_END:
 870                 output_op_binary(fn, insn);
 871                 break;
 872         case OP_BINCMP ... OP_BINCMP_END:
 873                 output_op_compare(fn, insn);
 874                 break;
 875         case OP_SEL:
 876                 output_op_sel(fn, insn);
 877                 break;
 878         case OP_SLICE:
 879                 assert(0);
 880                 break;
 881         case OP_NOT: {
 882                 LLVMValueRef src, target;
 883                 char target_name[64];
 884 
 885                 src = pseudo_to_value(fn, insn, insn->src);
 886 
 887                 pseudo_name(insn->target, target_name);
 888 
 889                 target = LLVMBuildNot(fn->builder, src, target_name);
 890 
 891                 insn->target->priv = target;
 892                 break;
 893         }
 894         case OP_NEG:
 895                 assert(0);
 896                 break;
 897         case OP_CONTEXT:
 898                 assert(0);
 899                 break;
 900         case OP_RANGE:
 901                 assert(0);
 902                 break;
 903         case OP_NOP:
 904                 assert(0);
 905                 break;
 906         case OP_DEATHNOTE:
 907                 break;
 908         case OP_ASM:
 909                 assert(0);
 910                 break;
 911         case OP_COPY:
 912                 assert(0);
 913                 break;
 914         default:
 915                 break;
 916         }
 917 }
 918 
 919 static void output_bb(struct function *fn, struct basic_block *bb, unsigned long generation)
 920 {
 921         struct instruction *insn;
 922 
 923         bb->generation = generation;
 924 
 925         FOR_EACH_PTR(bb->insns, insn) {
 926                 if (!insn->bb)
 927                         continue;
 928 
 929                 output_insn(fn, insn);
 930         }
 931         END_FOR_EACH_PTR(insn);
 932 }
 933 
 934 #define MAX_ARGS        64
 935 
 936 static void output_fn(LLVMModuleRef module, struct entrypoint *ep)
 937 {
 938         unsigned long generation = ++bb_generation;
 939         struct symbol *sym = ep->name;
 940         struct symbol *base_type = sym->ctype.base_type;
 941         struct symbol *ret_type = sym->ctype.base_type->ctype.base_type;
 942         LLVMTypeRef arg_types[MAX_ARGS];
 943         LLVMTypeRef return_type;
 944         struct function function = { .module = module };
 945         struct basic_block *bb;
 946         struct symbol *arg;
 947         const char *name;
 948         int nr_args = 0;
 949 
 950         FOR_EACH_PTR(base_type->arguments, arg) {
 951                 struct symbol *arg_base_type = arg->ctype.base_type;
 952 
 953                 arg_types[nr_args++] = symbol_type(module, arg_base_type);
 954         } END_FOR_EACH_PTR(arg);
 955 
 956         name = show_ident(sym->ident);
 957 
 958         return_type = symbol_type(module, ret_type);
 959 
 960         function.type = LLVMFunctionType(return_type, arg_types, nr_args, 0);
 961 
 962         function.fn = LLVMAddFunction(module, name, function.type);
 963         LLVMSetFunctionCallConv(function.fn, LLVMCCallConv);
 964 
 965         LLVMSetLinkage(function.fn, function_linkage(sym));
 966 
 967         function.builder = LLVMCreateBuilder();
 968 
 969         static int nr_bb;
 970 
 971         FOR_EACH_PTR(ep->bbs, bb) {
 972                 if (bb->generation == generation)
 973                         continue;
 974 
 975                 LLVMBasicBlockRef bbr;
 976                 char bbname[32];
 977                 struct instruction *insn;
 978 
 979                 sprintf(bbname, "L%d", nr_bb++);
 980                 bbr = LLVMAppendBasicBlock(function.fn, bbname);
 981 
 982                 bb->priv = bbr;
 983 
 984                 /* allocate alloca for each phi */
 985                 FOR_EACH_PTR(bb->insns, insn) {
 986                         LLVMBasicBlockRef entrybbr;
 987                         LLVMTypeRef phi_type;
 988                         LLVMValueRef ptr;
 989 
 990                         if (!insn->bb || insn->opcode != OP_PHI)
 991                                 continue;
 992                         /* insert alloca into entry block */
 993                         entrybbr = LLVMGetEntryBasicBlock(function.fn);
 994                         LLVMPositionBuilderAtEnd(function.builder, entrybbr);
 995                         phi_type = insn_symbol_type(module, insn);
 996                         ptr = LLVMBuildAlloca(function.builder, phi_type, "");
 997                         /* emit forward load for phi */
 998                         LLVMClearInsertionPosition(function.builder);
 999                         insn->target->priv = LLVMBuildLoad(function.builder, ptr, "phi");
1000                 } END_FOR_EACH_PTR(insn);
1001         }
1002         END_FOR_EACH_PTR(bb);
1003 
1004         FOR_EACH_PTR(ep->bbs, bb) {
1005                 if (bb->generation == generation)
1006                         continue;
1007 
1008                 LLVMPositionBuilderAtEnd(function.builder, bb->priv);
1009 
1010                 output_bb(&function, bb, generation);
1011         }
1012         END_FOR_EACH_PTR(bb);
1013 }
1014 
1015 static LLVMValueRef output_data(LLVMModuleRef module, struct symbol *sym)
1016 {
1017         struct expression *initializer = sym->initializer;
1018         LLVMValueRef initial_value;
1019         LLVMValueRef data;
1020         const char *name;
1021 
1022         if (initializer) {
1023                 switch (initializer->type) {
1024                 case EXPR_VALUE:
1025                         initial_value = LLVMConstInt(symbol_type(module, sym), initializer->value, 1);
1026                         break;
1027                 case EXPR_SYMBOL: {
1028                         struct symbol *sym = initializer->symbol;
1029 
1030                         initial_value = LLVMGetNamedGlobal(module, show_ident(sym->ident));
1031                         if (!initial_value)
1032                                 initial_value = output_data(module, sym);
1033                         break;
1034                 }
1035                 case EXPR_STRING: {
1036                         const char *s = initializer->string->data;
1037 
1038                         initial_value = LLVMConstString(strdup(s), strlen(s) + 1, true);
1039                         break;
1040                 }
1041                 default:
1042                         assert(0);
1043                 }
1044         } else {
1045                 LLVMTypeRef type = symbol_type(module, sym);
1046 
1047                 initial_value = LLVMConstNull(type);
1048         }
1049 
1050         name = show_ident(sym->ident);
1051 
1052         data = LLVMAddGlobal(module, LLVMTypeOf(initial_value), name);
1053 
1054         LLVMSetLinkage(data, data_linkage(sym));
1055         if (sym->ctype.modifiers & MOD_CONST)
1056                 LLVMSetGlobalConstant(data, 1);
1057         if (sym->ctype.modifiers & MOD_TLS)
1058                 LLVMSetThreadLocal(data, 1);
1059         if (sym->ctype.alignment)
1060                 LLVMSetAlignment(data, sym->ctype.alignment);
1061 
1062         if (!(sym->ctype.modifiers & MOD_EXTERN))
1063                 LLVMSetInitializer(data, initial_value);
1064 
1065         return data;
1066 }
1067 
1068 static int is_prototype(struct symbol *sym)
1069 {
1070         if (sym->type == SYM_NODE)
1071                 sym = sym->ctype.base_type;
1072         return sym && sym->type == SYM_FN && !sym->stmt;
1073 }
1074 
1075 static int compile(LLVMModuleRef module, struct symbol_list *list)
1076 {
1077         struct symbol *sym;
1078 
1079         FOR_EACH_PTR(list, sym) {
1080                 struct entrypoint *ep;
1081                 expand_symbol(sym);
1082 
1083                 if (is_prototype(sym))
1084                         continue;
1085 
1086                 ep = linearize_symbol(sym);
1087                 if (ep)
1088                         output_fn(module, ep);
1089                 else
1090                         output_data(module, sym);
1091         }
1092         END_FOR_EACH_PTR(sym);
1093 
1094         return 0;
1095 }
1096 
1097 #ifndef LLVM_DEFAULT_TARGET_TRIPLE
1098 #define LLVM_DEFAULT_TARGET_TRIPLE LLVM_HOSTTRIPLE
1099 #endif
1100 
1101 #define X86_LINUX_LAYOUT \
1102         "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-" \
1103         "i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-" \
1104         "a0:0:64-f80:32:32-n8:16:32-S128"
1105 
1106 #define X86_64_LINUX_LAYOUT \
1107         "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-" \
1108         "i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-" \
1109         "a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
1110 
1111 static void set_target(LLVMModuleRef module)
1112 {
1113         char target[] = LLVM_DEFAULT_TARGET_TRIPLE;
1114         const char *arch, *vendor, *os, *env, *layout = NULL;
1115         char triple[256];
1116 
1117         arch = strtok(target, "-");
1118         vendor = strtok(NULL, "-");
1119         os = strtok(NULL, "-");
1120         env = strtok(NULL, "-");
1121 
1122         if (!os)
1123                 return;
1124         if (!env)
1125                 env = "unknown";
1126 
1127         if (!strcmp(arch, "x86_64") && !strcmp(os, "linux")) {
1128                 if (arch_m64) {
1129                         layout = X86_64_LINUX_LAYOUT;
1130                 } else {
1131                         arch = "i386";
1132                         layout = X86_LINUX_LAYOUT;
1133                 }
1134         }
1135 
1136         /* unsupported target */
1137         if (!layout)
1138                 return;
1139 
1140         snprintf(triple, sizeof(triple), "%s-%s-%s-%s", arch, vendor, os, env);
1141         LLVMSetTarget(module, triple);
1142         LLVMSetDataLayout(module, layout);
1143 }
1144 
1145 int main(int argc, char **argv)
1146 {
1147         struct string_list *filelist = NULL;
1148         struct symbol_list *symlist;
1149         LLVMModuleRef module;
1150         char *file;
1151 
1152         symlist = sparse_initialize(argc, argv, &filelist);
1153 
1154         module = LLVMModuleCreateWithName("sparse");
1155         set_target(module);
1156 
1157         compile(module, symlist);
1158 
1159         /* need ->phi_users */
1160         dbg_dead = 1;
1161         FOR_EACH_PTR_NOTAG(filelist, file) {
1162                 symlist = sparse(file);
1163                 if (die_if_error)
1164                         return 1;
1165                 compile(module, symlist);
1166         } END_FOR_EACH_PTR_NOTAG(file);
1167 
1168         LLVMVerifyModule(module, LLVMPrintMessageAction, NULL);
1169 
1170         LLVMWriteBitcodeToFD(module, STDOUT_FILENO, 0, 0);
1171 
1172         LLVMDisposeModule(module);
1173 
1174         report_stats();
1175         return 0;
1176 }