• source navigation  • diff markup  • identifier search  • freetext search  • 

Sources/ucode/compiler.c

  1 /*
  2  * Copyright (C) 2020-2021 Jo-Philipp Wich <jo@mein.io>
  3  *
  4  * Permission to use, copy, modify, and/or distribute this software for any
  5  * purpose with or without fee is hereby granted, provided that the above
  6  * copyright notice and this permission notice appear in all copies.
  7  *
  8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 15  */
 16 
 17 #include <assert.h>
 18 #include <errno.h>
 19 
 20 #include "ucode/compiler.h"
 21 #include "ucode/chunk.h"
 22 #include "ucode/vm.h" /* I_* */
 23 #include "ucode/source.h"
 24 #include "ucode/program.h"
 25 #include "ucode/lib.h" /* uc_error_context_format() */
 26 
 27 #ifndef NO_COMPILE
 28 
 29 static void uc_compiler_compile_unary(uc_compiler_t *compiler);
 30 static void uc_compiler_compile_binary(uc_compiler_t *compiler);
 31 static void uc_compiler_compile_delete(uc_compiler_t *compiler);
 32 static void uc_compiler_compile_importcall(uc_compiler_t *compiler);
 33 static void uc_compiler_compile_paren(uc_compiler_t *compiler);
 34 static void uc_compiler_compile_call(uc_compiler_t *compiler);
 35 static void uc_compiler_compile_post_inc(uc_compiler_t *compiler);
 36 static void uc_compiler_compile_constant(uc_compiler_t *compiler);
 37 static void uc_compiler_compile_template(uc_compiler_t *compiler);
 38 static void uc_compiler_compile_comma(uc_compiler_t *compiler);
 39 static void uc_compiler_compile_labelexpr(uc_compiler_t *compiler);
 40 static void uc_compiler_compile_funcexpr(uc_compiler_t *compiler);
 41 static void uc_compiler_compile_and(uc_compiler_t *compiler);
 42 static void uc_compiler_compile_or(uc_compiler_t *compiler);
 43 static void uc_compiler_compile_nullish(uc_compiler_t *compiler);
 44 static void uc_compiler_compile_dot(uc_compiler_t *compiler);
 45 static void uc_compiler_compile_subscript(uc_compiler_t *compiler);
 46 static void uc_compiler_compile_ternary(uc_compiler_t *compiler);
 47 static void uc_compiler_compile_array(uc_compiler_t *compiler);
 48 static void uc_compiler_compile_object(uc_compiler_t *compiler);
 49 
 50 static uc_tokentype_t uc_compiler_compile_declaration(uc_compiler_t *compiler);
 51 static uc_tokentype_t uc_compiler_compile_statement(uc_compiler_t *compiler);
 52 static uc_tokentype_t uc_compiler_compile_expstmt(uc_compiler_t *compiler);
 53 
 54 static uc_parse_rule_t
 55 uc_compiler_parse_rules[TK_ERROR + 1] = {
 56         [TK_LPAREN]             = { uc_compiler_compile_paren, uc_compiler_compile_call, P_CALL },
 57         [TK_QLPAREN]    = { NULL, uc_compiler_compile_call, P_CALL },
 58         [TK_SUB]                = { uc_compiler_compile_unary, uc_compiler_compile_binary, P_ADD },
 59         [TK_ADD]                = { uc_compiler_compile_unary, uc_compiler_compile_binary, P_ADD },
 60         [TK_COMPL]              = { uc_compiler_compile_unary, NULL, P_UNARY },
 61         [TK_NOT]                = { uc_compiler_compile_unary, NULL, P_UNARY },
 62         [TK_DELETE]             = { uc_compiler_compile_delete, NULL, P_UNARY },
 63         [TK_IMPORT]             = { uc_compiler_compile_importcall, NULL, P_UNARY },
 64         [TK_INC]                = { uc_compiler_compile_unary, uc_compiler_compile_post_inc, P_INC },
 65         [TK_DEC]                = { uc_compiler_compile_unary, uc_compiler_compile_post_inc, P_INC },
 66         [TK_DIV]                = { NULL, uc_compiler_compile_binary, P_MUL },
 67         [TK_MUL]                = { NULL, uc_compiler_compile_binary, P_MUL },
 68         [TK_MOD]                = { NULL, uc_compiler_compile_binary, P_MUL },
 69         [TK_EXP]                = { NULL, uc_compiler_compile_binary, P_EXP },
 70         [TK_NUMBER]             = { uc_compiler_compile_constant, NULL, P_NONE },
 71         [TK_DOUBLE]             = { uc_compiler_compile_constant, NULL, P_NONE },
 72         [TK_STRING]             = { uc_compiler_compile_constant, NULL, P_NONE },
 73         [TK_TRUE]               = { uc_compiler_compile_constant, NULL, P_NONE },
 74         [TK_FALSE]              = { uc_compiler_compile_constant, NULL, P_NONE },
 75         [TK_NULL]               = { uc_compiler_compile_constant, NULL, P_NONE },
 76         [TK_THIS]               = { uc_compiler_compile_constant, NULL, P_NONE },
 77         [TK_REGEXP]             = { uc_compiler_compile_constant, NULL, P_NONE },
 78         [TK_TEMPLATE]   = { uc_compiler_compile_template, NULL, P_NONE },
 79         [TK_COMMA]              = { NULL, uc_compiler_compile_comma, P_COMMA },
 80         [TK_LABEL]              = { uc_compiler_compile_labelexpr, NULL, P_NONE },
 81         [TK_FUNC]               = { uc_compiler_compile_funcexpr, NULL, P_NONE },
 82         [TK_AND]                = { NULL, uc_compiler_compile_and, P_AND },
 83         [TK_OR]                 = { NULL, uc_compiler_compile_or, P_OR },
 84         [TK_NULLISH]    = { NULL, uc_compiler_compile_nullish, P_OR },
 85         [TK_BOR]                = { NULL, uc_compiler_compile_binary, P_BOR },
 86         [TK_BXOR]               = { NULL, uc_compiler_compile_binary, P_BXOR },
 87         [TK_BAND]               = { NULL, uc_compiler_compile_binary, P_BAND },
 88         [TK_EQ]                 = { NULL, uc_compiler_compile_binary, P_EQUAL },
 89         [TK_EQS]                = { NULL, uc_compiler_compile_binary, P_EQUAL },
 90         [TK_NE]                 = { NULL, uc_compiler_compile_binary, P_EQUAL },
 91         [TK_NES]                = { NULL, uc_compiler_compile_binary, P_EQUAL },
 92         [TK_LT]                 = { NULL, uc_compiler_compile_binary, P_COMPARE },
 93         [TK_LE]                 = { NULL, uc_compiler_compile_binary, P_COMPARE },
 94         [TK_GT]                 = { NULL, uc_compiler_compile_binary, P_COMPARE },
 95         [TK_GE]                 = { NULL, uc_compiler_compile_binary, P_COMPARE },
 96         [TK_IN]                 = { NULL, uc_compiler_compile_binary, P_COMPARE },
 97         [TK_LSHIFT]             = { NULL, uc_compiler_compile_binary, P_SHIFT },
 98         [TK_RSHIFT]             = { NULL, uc_compiler_compile_binary, P_SHIFT },
 99         [TK_DOT]                = { NULL, uc_compiler_compile_dot, P_CALL },
100         [TK_QDOT]               = { NULL, uc_compiler_compile_dot, P_CALL },
101         [TK_LBRACK]             = { uc_compiler_compile_array, uc_compiler_compile_subscript, P_CALL },
102         [TK_QLBRACK]    = { NULL, uc_compiler_compile_subscript, P_CALL },
103         [TK_QMARK]              = { NULL, uc_compiler_compile_ternary, P_TERNARY },
104         [TK_LBRACE]             = { uc_compiler_compile_object, NULL, P_NONE },
105 };
106 
107 static ssize_t
108 uc_compiler_declare_local(uc_compiler_t *compiler, uc_value_t *name, bool constant);
109 
110 static ssize_t
111 uc_compiler_initialize_local(uc_compiler_t *compiler);
112 
113 static bool
114 uc_compiler_exprstack_is(uc_compiler_t *compiler, uc_exprflag_t flag)
115 {
116         uc_exprstack_t *expr;
117 
118         for (expr = compiler->exprstack; expr; expr = expr->parent)
119                 if (expr->flags & flag)
120                         return true;
121 
122         return false;
123 }
124 
125 static void
126 uc_compiler_init(uc_compiler_t *compiler, const char *name, uc_source_t *source, size_t srcpos, uc_program_t *program, bool strict)
127 {
128         uc_value_t *varname = ucv_string_new("(callee)");
129         uc_function_t *fn;
130 
131         compiler->scope_depth = 0;
132 
133         compiler->program = program;
134         compiler->function = uc_program_function_new(program, name, source, srcpos);
135 
136         compiler->locals.count = 0;
137         compiler->locals.entries = NULL;
138 
139         compiler->upvals.count = 0;
140         compiler->upvals.entries = NULL;
141 
142         compiler->patchlist = NULL;
143 
144         compiler->parent = NULL;
145 
146         compiler->current_srcpos = srcpos;
147 
148         fn = (uc_function_t *)compiler->function;
149         fn->strict = strict;
150 
151         /* reserve stack slot 0 */
152         uc_compiler_declare_local(compiler, varname, false);
153         uc_compiler_initialize_local(compiler);
154         ucv_put(varname);
155 }
156 
157 static uc_chunk_t *
158 uc_compiler_current_chunk(uc_compiler_t *compiler)
159 {
160         uc_function_t *fn = (uc_function_t *)compiler->function;
161 
162         return &fn->chunk;
163 }
164 
165 static uc_source_t *
166 uc_compiler_current_source(uc_compiler_t *compiler)
167 {
168         return uc_program_function_source(compiler->function);
169 }
170 
171 __attribute__((format(printf, 3, 0))) static void
172 uc_compiler_syntax_error(uc_compiler_t *compiler, size_t off, const char *fmt, ...)
173 {
174         uc_source_t *source = uc_compiler_current_source(compiler);
175         uc_stringbuf_t *buf = compiler->parser->error;
176         size_t line = 0, byte = 0, len = 0;
177         va_list ap;
178         char *s;
179 
180         if (compiler->parser->synchronizing)
181                 return;
182 
183         compiler->parser->synchronizing = true;
184 
185         if (!buf)
186                 buf = compiler->parser->error = xprintbuf_new();
187 
188         if (!off)
189                 off = uc_program_function_srcpos(compiler->function,
190                         uc_compiler_current_chunk(compiler)->count);
191 
192         byte = off;
193         line = uc_source_get_line(source, &byte);
194 
195         va_start(ap, fmt);
196         len = xvasprintf(&s, fmt, ap);
197         va_end(ap);
198 
199         ucv_stringbuf_append(buf, "Syntax error: ");
200         ucv_stringbuf_addstr(buf, s, len);
201         ucv_stringbuf_append(buf, "\n");
202 
203         free(s);
204 
205         if (line) {
206                 ucv_stringbuf_append(buf, "In ");
207 
208                 if (compiler->program->sources.count > 1) {
209                         len = strlen(source->filename);
210 
211                         if (len > 48)
212                                 ucv_stringbuf_printf(buf, "...%s", source->filename + len - 45);
213                         else
214                                 ucv_stringbuf_addstr(buf, source->filename, len);
215 
216                         ucv_stringbuf_append(buf, ", ");
217                 }
218 
219                 ucv_stringbuf_printf(buf, "line %zu, byte %zu:\n", line, byte);
220         }
221 
222         if (uc_error_context_format(buf, source, NULL, off))
223                 ucv_stringbuf_append(buf, "\n\n");
224 }
225 
226 static size_t
227 uc_compiler_set_srcpos(uc_compiler_t *compiler, size_t srcpos)
228 {
229         size_t delta;
230 
231         /* ensure that lines counts are strictly increasing */
232         assert(srcpos == 0 || srcpos >= compiler->current_srcpos);
233 
234         delta = srcpos ? srcpos - compiler->current_srcpos : 0;
235         compiler->current_srcpos += delta;
236 
237         return delta;
238 }
239 
240 static void
241 uc_compiler_parse_advance(uc_compiler_t *compiler)
242 {
243         ucv_put(compiler->parser->prev.uv);
244         compiler->parser->prev = compiler->parser->curr;
245 
246         while (true) {
247                 uc_token_t *tok = uc_lexer_next_token(&compiler->parser->lex);
248 
249                 if (tok->type == TK_COMMENT || tok->type == TK_LSTM) {
250                         ucv_put(tok->uv);
251                         continue;
252                 }
253                 else if (tok->type == TK_RSTM) {
254                         tok->type = TK_SCOL;
255                 }
256 
257                 compiler->parser->curr = *tok;
258 
259                 if (compiler->parser->curr.type != TK_ERROR)
260                         break;
261 
262                 uc_compiler_syntax_error(compiler, compiler->parser->curr.pos, "%s",
263                         ucv_string_get(compiler->parser->curr.uv));
264 
265                 ucv_put(compiler->parser->curr.uv);
266                 compiler->parser->curr.uv = NULL;
267         }
268 }
269 
270 static void
271 uc_compiler_parse_consume(uc_compiler_t *compiler, uc_tokentype_t type)
272 {
273         if (compiler->parser->curr.type == type) {
274                 uc_compiler_parse_advance(compiler);
275 
276                 return;
277         }
278 
279         uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
280                 "Unexpected token\nExpecting %s", uc_tokenname(type));
281 }
282 
283 static bool
284 uc_compiler_parse_check(uc_compiler_t *compiler, uc_tokentype_t type)
285 {
286         return (compiler->parser->curr.type == type);
287 }
288 
289 static bool
290 uc_compiler_parse_match(uc_compiler_t *compiler, uc_tokentype_t type)
291 {
292         if (!uc_compiler_parse_check(compiler, type))
293                 return false;
294 
295         uc_compiler_parse_advance(compiler);
296 
297         return true;
298 }
299 
300 static bool
301 uc_compiler_keyword_check(uc_compiler_t *compiler, const char *keyword)
302 {
303         size_t keywordlen = strlen(keyword);
304 
305         return (compiler->parser->curr.type == TK_LABEL &&
306                 ucv_string_length(compiler->parser->curr.uv) == keywordlen &&
307                 strcmp(ucv_string_get(compiler->parser->curr.uv), keyword) == 0);
308 }
309 
310 static bool
311 uc_compiler_keyword_match(uc_compiler_t *compiler, const char *keyword)
312 {
313         if (!uc_compiler_keyword_check(compiler, keyword))
314                 return false;
315 
316         uc_compiler_parse_advance(compiler);
317 
318         return true;
319 }
320 
321 static void
322 uc_compiler_keyword_consume(uc_compiler_t *compiler, const char *keyword)
323 {
324         if (uc_compiler_keyword_check(compiler, keyword)) {
325                 uc_compiler_parse_advance(compiler);
326 
327                 return;
328         }
329 
330         uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
331                 "Unexpected token\nExpecting '%s'", keyword);
332 }
333 
334 static void
335 uc_compiler_parse_synchronize(uc_compiler_t *compiler)
336 {
337         compiler->parser->synchronizing = false;
338 
339         while (compiler->parser->curr.type != TK_EOF) {
340                 if (compiler->parser->prev.type == TK_SCOL)
341                         return;
342 
343                 switch (compiler->parser->curr.type) {
344                 case TK_IF:
345                 case TK_FOR:
346                 case TK_WHILE:
347                 case TK_SWITCH:
348                 case TK_FUNC:
349                 case TK_TRY:
350                 case TK_RETURN:
351                 case TK_BREAK:
352                 case TK_CONTINUE:
353                 case TK_LOCAL:
354                         return;
355 
356                 default:
357                         break;
358                 }
359 
360                 uc_compiler_parse_advance(compiler);
361         }
362 }
363 
364 static uc_parse_rule_t *
365 uc_compiler_parse_rule(uc_tokentype_t type)
366 {
367         return &uc_compiler_parse_rules[type];
368 }
369 
370 static bool
371 uc_compiler_parse_at_assignment_op(uc_compiler_t *compiler)
372 {
373         switch (compiler->parser->curr.type) {
374         case TK_ASBAND:
375         case TK_ASBXOR:
376         case TK_ASBOR:
377         case TK_ASLEFT:
378         case TK_ASRIGHT:
379         case TK_ASMUL:
380         case TK_ASDIV:
381         case TK_ASMOD:
382         case TK_ASADD:
383         case TK_ASSUB:
384         case TK_ASAND:
385         case TK_ASOR:
386         case TK_ASEXP:
387         case TK_ASNULLISH:
388         case TK_ASSIGN:
389                 return true;
390 
391         default:
392                 return false;
393         }
394 }
395 
396 static void
397 uc_compiler_backpatch(uc_compiler_t *compiler, size_t break_addr, size_t next_addr);
398 
399 static void
400 uc_compiler_parse_precedence_for_token(uc_compiler_t *compiler, uc_precedence_t precedence, uc_token_t *token)
401 {
402         uc_parse_rule_t *rule;
403 
404         rule = uc_compiler_parse_rule(token->type);
405 
406         if (!rule->prefix) {
407                 uc_compiler_syntax_error(compiler, token->pos, "Expecting expression");
408 
409                 return;
410         }
411 
412         uc_compiler_exprstack_push(compiler, token->type,
413                 (precedence <= P_ASSIGN) ? F_ASSIGNABLE : 0);
414 
415         compiler->patchlist = &(uc_patchlist_t){
416                 .parent = compiler->patchlist,
417                 .token = TK_EXP,
418         };
419 
420         rule->prefix(compiler);
421 
422         while (precedence <= uc_compiler_parse_rule(compiler->parser->curr.type)->precedence) {
423                 compiler->exprstack->token = compiler->parser->curr.type;
424 
425                 rule = uc_compiler_parse_rule(compiler->exprstack->token);
426 
427                 if (!rule->infix) {
428                         uc_compiler_syntax_error(compiler, compiler->parser->curr.pos, "Expecting ';' or binary operator");
429                         uc_compiler_parse_advance(compiler);
430 
431                         return;
432                 }
433 
434                 /* allow reserved words in property accessors */
435                 if (rule->infix == uc_compiler_compile_dot)
436                         compiler->parser->lex.no_keyword = true;
437 
438                 uc_compiler_parse_advance(compiler);
439 
440                 rule->infix(compiler);
441         }
442 
443         uc_compiler_backpatch(compiler, compiler->patchlist->depth, 0);
444 
445         uc_compiler_exprstack_pop(compiler);
446 }
447 
448 static void
449 uc_compiler_parse_precedence(uc_compiler_t *compiler, uc_precedence_t precedence)
450 {
451         uc_token_t token = compiler->parser->curr;
452         uc_parse_rule_t *rule = uc_compiler_parse_rule(token.type);
453 
454         /* allow reserved words as property names in object literals */
455         if (rule->prefix == uc_compiler_compile_object)
456                 compiler->parser->lex.no_keyword = true;
457 
458         /* unless a sub-expression follows, treat subsequent slash as division
459          * operator and not as beginning of regexp literal */
460         if (rule->prefix != uc_compiler_compile_paren &&
461             rule->prefix != uc_compiler_compile_unary &&
462             rule->prefix != uc_compiler_compile_array)
463                 compiler->parser->lex.no_regexp = true;
464 
465         uc_compiler_parse_advance(compiler);
466         uc_compiler_parse_precedence_for_token(compiler, precedence, &token);
467 }
468 
469 static size_t
470 uc_compiler_reladdr32(uc_compiler_t *compiler, size_t from, size_t to)
471 {
472         ssize_t delta = to - from;
473 
474         if (delta < -0x7fffffff || delta > 0x7fffffff) {
475                 uc_compiler_syntax_error(compiler, 0, "Jump address too far");
476 
477                 return 0;
478         }
479 
480         return (size_t)(delta + 0x7fffffff);
481 }
482 
483 static size_t
484 uc_compiler_reladdr16(uc_compiler_t *compiler, size_t from, size_t to)
485 {
486         ssize_t delta = to - from;
487 
488         if (delta < -0x7fff || delta > 0x7fff) {
489                 uc_compiler_syntax_error(compiler, 0, "Jump address too far");
490 
491                 return 0;
492         }
493 
494         return (size_t)(delta + 0x7fff);
495 }
496 
497 static size_t
498 uc_compiler_emit_insn(uc_compiler_t *compiler, size_t srcpos, uc_vm_insn_t insn)
499 {
500         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
501         size_t lineoff = uc_compiler_set_srcpos(compiler, srcpos);
502 
503         compiler->last_insn = uc_chunk_add(chunk, (uint8_t)insn, lineoff);
504 
505         return compiler->last_insn;
506 }
507 
508 static size_t
509 uc_compiler_emit_u8(uc_compiler_t *compiler, size_t srcpos, uint8_t n)
510 {
511         return uc_chunk_add(
512                 uc_compiler_current_chunk(compiler),
513                 n,
514                 uc_compiler_set_srcpos(compiler, srcpos));
515 }
516 
517 static size_t
518 uc_compiler_emit_u16(uc_compiler_t *compiler, size_t srcpos, uint16_t n)
519 {
520         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
521         size_t lineoff = uc_compiler_set_srcpos(compiler, srcpos);
522 
523         uc_chunk_add(chunk, n / 0x100, lineoff);
524         uc_chunk_add(chunk, n % 0x100, 0);
525 
526         return chunk->count - 2;
527 }
528 
529 static size_t
530 uc_compiler_emit_u32(uc_compiler_t *compiler, size_t srcpos, uint32_t n)
531 {
532         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
533         size_t lineoff = uc_compiler_set_srcpos(compiler, srcpos);
534 
535         uc_chunk_add(chunk, n / 0x1000000, lineoff);
536         uc_chunk_add(chunk, (n / 0x10000) % 0x100, 0);
537         uc_chunk_add(chunk, (n / 0x100) % 0x100, 0);
538         uc_chunk_add(chunk, n % 0x100, 0);
539 
540         return chunk->count - 4;
541 }
542 
543 static size_t
544 uc_compiler_emit_s32(uc_compiler_t *compiler, size_t srcpos, int32_t n)
545 {
546         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
547         size_t lineoff = uc_compiler_set_srcpos(compiler, srcpos);
548         uint32_t v;
549 
550         if (n <= 0)
551                 v = n + 0x7fffffff;
552         else
553                 v = (uint32_t)n + 0x7fffffff;
554 
555         uc_chunk_add(chunk, v / 0x1000000, lineoff);
556         uc_chunk_add(chunk, (v / 0x10000) % 0x100, 0);
557         uc_chunk_add(chunk, (v / 0x100) % 0x100, 0);
558         uc_chunk_add(chunk, v % 0x100, 0);
559 
560         return chunk->count - 4;
561 }
562 
563 static uint32_t
564 uc_compiler_get_u32(uc_compiler_t *compiler, size_t off)
565 {
566         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
567 
568         return chunk->entries[off + 0] * 0x1000000 +
569                chunk->entries[off + 1] * 0x10000 +
570                chunk->entries[off + 2] * 0x100 +
571                chunk->entries[off + 3];
572 }
573 
574 static void
575 uc_compiler_set_u32(uc_compiler_t *compiler, size_t off, uint32_t n)
576 {
577         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
578 
579         chunk->entries[off + 0] = n / 0x1000000;
580         chunk->entries[off + 1] = (n / 0x10000) % 0x100;
581         chunk->entries[off + 2] = (n / 0x100) % 0x100;
582         chunk->entries[off + 3] = n % 0x100;
583 }
584 
585 static size_t
586 uc_compiler_emit_constant_index(uc_compiler_t *compiler, size_t srcpos, uc_value_t *val)
587 {
588         size_t cidx = uc_program_add_constant(compiler->program, val);
589 
590         uc_compiler_emit_u32(compiler, srcpos, cidx);
591 
592         return cidx;
593 }
594 
595 static size_t
596 uc_compiler_emit_constant(uc_compiler_t *compiler, size_t srcpos, uc_value_t *val)
597 {
598         size_t cidx;
599 
600         uc_compiler_emit_insn(compiler, srcpos, I_LOAD);
601 
602         cidx = uc_compiler_emit_constant_index(compiler, srcpos, val);
603 
604         return cidx;
605 }
606 
607 static size_t
608 uc_compiler_emit_regexp(uc_compiler_t *compiler, size_t srcpos, uc_value_t *val)
609 {
610         size_t cidx = uc_program_add_constant(compiler->program, val);
611 
612         uc_compiler_emit_insn(compiler, srcpos, I_LREXP);
613         uc_compiler_emit_u32(compiler, 0, cidx);
614 
615         return cidx;
616 }
617 
618 static size_t
619 uc_compiler_emit_jmp(uc_compiler_t *compiler, size_t srcpos)
620 {
621         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
622 
623         uc_compiler_emit_insn(compiler, srcpos, I_JMP);
624         uc_compiler_emit_u32(compiler, 0, 0);
625 
626         return chunk->count - 5;
627 }
628 
629 static size_t
630 uc_compiler_emit_jmpz(uc_compiler_t *compiler, size_t srcpos)
631 {
632         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
633 
634         uc_compiler_emit_insn(compiler, srcpos, I_JMPZ);
635         uc_compiler_emit_u32(compiler, 0, 0);
636 
637         return chunk->count - 5;
638 }
639 
640 static size_t
641 uc_compiler_emit_jmp_dest(uc_compiler_t *compiler, size_t srcpos, uint32_t dest)
642 {
643         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
644 
645         uc_compiler_emit_insn(compiler, srcpos, I_JMP);
646         uc_compiler_emit_u32(compiler, 0, uc_compiler_reladdr32(compiler, chunk->count - 1, dest));
647 
648         return chunk->count - 5;
649 }
650 
651 static size_t
652 uc_compiler_emit_jmpnt(uc_compiler_t *compiler, size_t srcpos, uint16_t types, uint8_t depth)
653 {
654         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
655 
656         uc_vector_push(compiler->patchlist,
657                 uc_compiler_emit_insn(compiler, srcpos, I_JMPNT));
658 
659         uc_compiler_emit_u32(compiler, 0,
660                 uc_compiler_reladdr16(compiler, 0, TK_BREAK)
661                         | ((types & 0x1fff) << 16)
662                         | ((depth & 0x7) << 29));
663 
664         return chunk->count - 5;
665 }
666 
667 static size_t
668 uc_compiler_emit_copy(uc_compiler_t *compiler, size_t srcpos, uint8_t depth)
669 {
670         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
671 
672         uc_compiler_emit_insn(compiler, srcpos, I_COPY);
673         uc_compiler_emit_u8(compiler, 0, depth);
674 
675         return chunk->count - 2;
676 }
677 
678 static ssize_t
679 uc_compiler_get_jmpaddr(uc_compiler_t *compiler, size_t off)
680 {
681         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
682         size_t width = (chunk->entries[off] == I_JMPNT) ? 2 : 4;
683 
684         assert(chunk->entries[off] == I_JMP || chunk->entries[off] == I_JMPZ || chunk->entries[off] == I_JMPNT);
685         assert(off + 4 < chunk->count);
686 
687         if (width == 2)
688                 return (
689                         chunk->entries[off + 3] * 0x100UL +
690                         chunk->entries[off + 4]
691                 ) - 0x7fff;
692         else
693                 return (
694                         chunk->entries[off + 1] * 0x1000000UL +
695                         chunk->entries[off + 2] * 0x10000UL +
696                         chunk->entries[off + 3] * 0x100UL +
697                         chunk->entries[off + 4]
698                 ) - 0x7fffffff;
699 }
700 
701 static void
702 uc_compiler_set_jmpaddr(uc_compiler_t *compiler, size_t off, uint32_t dest)
703 {
704         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
705         size_t width = (chunk->entries[off] == I_JMPNT) ? 2 : 4;
706         size_t addr;
707 
708         assert(chunk->entries[off] == I_JMP || chunk->entries[off] == I_JMPZ || chunk->entries[off] == I_JMPNT);
709         assert(off + 4 < chunk->count);
710 
711         if (width == 2) {
712                 addr = uc_compiler_reladdr16(compiler, off, dest);
713                 chunk->entries[off + 3] = addr / 0x100;
714                 chunk->entries[off + 4] = addr % 0x100;
715         }
716         else {
717                 addr = uc_compiler_reladdr32(compiler, off, dest);
718                 chunk->entries[off + 1] = addr / 0x1000000;
719                 chunk->entries[off + 2] = (addr / 0x10000) % 0x100;
720                 chunk->entries[off + 3] = (addr / 0x100) % 0x100;
721                 chunk->entries[off + 4] = addr % 0x100;
722         }
723 }
724 
725 static void
726 uc_compiler_inc_exportnum(uc_compiler_t *compiler)
727 {
728         uc_source_t *root = uc_program_function_source(uc_program_entry(compiler->program));
729         uint64_t u;
730 
731         if (root->exports.count == 0) {
732                 uc_vector_push(&root->exports, ucv_uint64_new(1));
733         }
734         else {
735                 u = ucv_uint64_get(root->exports.entries[0]);
736 
737                 ucv_put(root->exports.entries[0]);
738 
739                 root->exports.entries[0] = ucv_uint64_new(u + 1);
740         }
741 }
742 
743 static size_t
744 uc_compiler_get_exportnum(uc_compiler_t *compiler)
745 {
746         uc_source_t *root = uc_program_function_source(uc_program_entry(compiler->program));
747 
748         return root->exports.count ? ucv_uint64_get(root->exports.entries[0]) : 0;
749 }
750 
751 static void
752 uc_compiler_emit_exports(uc_compiler_t *compiler) {
753         size_t i;
754 
755         if (!compiler->patchlist || compiler->patchlist->token != TK_EXPORT)
756                 return;
757 
758         for (i = 0; i < compiler->patchlist->count; i++) {
759                 uc_compiler_emit_insn(compiler, 0, I_EXPORT);
760                 uc_compiler_emit_u32(compiler, 0, compiler->patchlist->entries[i]);
761         }
762 }
763 
764 static uc_function_t *
765 uc_compiler_finish(uc_compiler_t *compiler, uc_tokentype_t last_statement_type)
766 {
767         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
768         uc_locals_t *locals = &compiler->locals;
769         uc_upvals_t *upvals = &compiler->upvals;
770         size_t i;
771 
772         if (compiler->function->module)
773                 uc_compiler_emit_exports(compiler);
774 
775         uc_compiler_emit_insn(compiler, 0, I_LNULL);
776         uc_compiler_emit_insn(compiler, 0, I_RETURN);
777 
778         for (i = 0; i < locals->count; i++) {
779                 uc_chunk_debug_add_variable(chunk,
780                         locals->entries[i].from,
781                         chunk->count,
782                         i,
783                         false,
784                         locals->entries[i].name);
785 
786                 ucv_put(locals->entries[i].name);
787         }
788 
789         for (i = 0; i < upvals->count; i++) {
790                 uc_chunk_debug_add_variable(chunk,
791                         0,
792                         chunk->count,
793                         i,
794                         true,
795                         upvals->entries[i].name);
796 
797                 ucv_put(upvals->entries[i].name);
798         }
799 
800         uc_vector_clear(locals);
801         uc_vector_clear(upvals);
802 
803         if (compiler->parser->error) {
804                 uc_program_function_free(compiler->function);
805 
806                 return NULL;
807         }
808 
809         return compiler->function;
810 }
811 
812 static void
813 uc_compiler_enter_scope(uc_compiler_t *compiler)
814 {
815         compiler->scope_depth++;
816 }
817 
818 static void
819 uc_compiler_leave_scope(uc_compiler_t *compiler)
820 {
821         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
822         uc_locals_t *locals = &compiler->locals;
823 
824         compiler->scope_depth--;
825 
826         while (locals->count > 0 && locals->entries[locals->count - 1].depth > (ssize_t)compiler->scope_depth) {
827                 locals->count--;
828 
829                 uc_chunk_debug_add_variable(chunk,
830                         locals->entries[locals->count].from,
831                         chunk->count,
832                         locals->count,
833                         false,
834                         locals->entries[locals->count].name);
835 
836                 ucv_put(locals->entries[locals->count].name);
837                 locals->entries[locals->count].name = NULL;
838 
839                 uc_compiler_emit_insn(compiler, 0,
840                         locals->entries[locals->count].captured ? I_CUPV : I_POP);
841         }
842 }
843 
844 static bool
845 uc_compiler_is_strict(uc_compiler_t *compiler)
846 {
847         uc_function_t *fn = (uc_function_t *)compiler->function;
848 
849         return fn->strict;
850 }
851 
852 static ssize_t
853 uc_compiler_declare_local(uc_compiler_t *compiler, uc_value_t *name, bool constant)
854 {
855         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
856         uc_locals_t *locals = &compiler->locals;
857         const char *str1, *str2;
858         size_t i, len1, len2;
859 
860         if (locals->count >= 0x00FFFFFF) {
861                 uc_compiler_syntax_error(compiler, 0, "Too many local variables");
862 
863                 return -1;
864         }
865 
866         str1 = ucv_string_get(name);
867         len1 = ucv_string_length(name);
868 
869         for (i = locals->count; i > 0; i--) {
870                 if (locals->entries[i - 1].depth != -1 && locals->entries[i - 1].depth < (ssize_t)compiler->scope_depth)
871                         break;
872 
873                 str2 = ucv_string_get(locals->entries[i - 1].name);
874                 len2 = ucv_string_length(locals->entries[i - 1].name);
875 
876                 if (len1 == len2 && !strcmp(str1, str2)) {
877                         if (locals->entries[i - 1].funcstub) {
878                                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
879                                         "Variable '%s' redeclared", str2);
880 
881                                 return -1;
882                         }
883 
884                         if (uc_compiler_is_strict(compiler)) {
885                                 uc_compiler_syntax_error(compiler, 0, "Variable '%s' redeclared", str2);
886 
887                                 return -1;
888                         }
889 
890                         return i - 1;
891                 }
892         }
893 
894         uc_vector_push(locals, {
895                 .name = ucv_get(name),
896                 .depth = -1,
897                 .captured = false,
898                 .from = chunk->count,
899                 .constant = constant
900         });
901 
902         return -1;
903 }
904 
905 static ssize_t
906 uc_compiler_initialize_local(uc_compiler_t *compiler)
907 {
908         uc_locals_t *locals = &compiler->locals;
909 
910         locals->entries[locals->count - 1].depth = compiler->scope_depth;
911 
912         return locals->count - 1;
913 }
914 
915 static ssize_t
916 uc_compiler_resolve_local(uc_compiler_t *compiler, uc_value_t *name, bool *constant)
917 {
918         uc_locals_t *locals = &compiler->locals;
919         const char *str1, *str2;
920         size_t i, len1, len2;
921 
922         str1 = ucv_string_get(name);
923         len1 = ucv_string_length(name);
924 
925         for (i = locals->count; i > 0; i--) {
926                 str2 = ucv_string_get(locals->entries[i - 1].name);
927                 len2 = ucv_string_length(locals->entries[i - 1].name);
928 
929                 if (len1 != len2 || strcmp(str1, str2))
930                         continue;
931 
932                 if (locals->entries[i - 1].depth == -1) {
933                         uc_compiler_syntax_error(compiler, 0,
934                                 "Can't access lexical declaration '%s' before initialization", str2);
935 
936                         return -1;
937                 }
938 
939                 *constant = locals->entries[i - 1].constant;
940 
941                 return i - 1;
942         }
943 
944         return -1;
945 }
946 
947 static ssize_t
948 uc_compiler_resolve_funcstub(uc_compiler_t *compiler, uc_value_t *name)
949 {
950         uc_locals_t *locals = &compiler->locals;
951         const char *str1, *str2;
952         size_t i, len1, len2;
953 
954         str1 = ucv_string_get(name);
955         len1 = ucv_string_length(name);
956 
957         for (i = locals->count; i > 0; i--) {
958                 if (locals->entries[i - 1].depth != -1 &&
959                     locals->entries[i - 1].depth < (ssize_t)compiler->scope_depth)
960                         break;
961 
962                 str2 = ucv_string_get(locals->entries[i - 1].name);
963                 len2 = ucv_string_length(locals->entries[i - 1].name);
964 
965                 if (len1 == len2 && !strcmp(str1, str2))
966                         return locals->entries[i - 1].funcstub ? (ssize_t)(i - 1) : -1;
967         }
968 
969         return -1;
970 }
971 
972 static ssize_t
973 uc_compiler_add_upval(uc_compiler_t *compiler, size_t idx, bool local, uc_value_t *name, bool constant)
974 {
975         uc_function_t *function = (uc_function_t *)compiler->function;
976         uc_upvals_t *upvals = &compiler->upvals;
977         uc_upval_t *uv;
978         size_t i;
979 
980         for (i = 0, uv = upvals->entries; i < upvals->count; i++, uv = upvals->entries + i)
981                 if (uv->index == idx && uv->local == local)
982                         return i;
983 
984         /* XXX: encoding... */
985         if (upvals->count >= (2 << 14)) {
986                 uc_compiler_syntax_error(compiler, 0, "Too many upvalues");
987 
988                 return -1;
989         }
990 
991         uc_vector_push(upvals, {
992                 .local = local,
993                 .index = idx,
994                 .name  = ucv_get(name),
995                 .constant = constant
996         });
997 
998         function->nupvals++;
999 
1000         return upvals->count - 1;
1001 }
1002 
1003 static ssize_t
1004 uc_compiler_resolve_upval(uc_compiler_t *compiler, uc_value_t *name, bool *constant)
1005 {
1006         uc_upvals_t *upvals = &compiler->upvals;
1007         uc_upval_t *uv;
1008         ssize_t idx;
1009         size_t i;
1010 
1011         if (!compiler->parent) {
1012                 for (i = 0, uv = upvals->entries; i < upvals->count; i++, uv = upvals->entries + i) {
1013                         if (ucv_is_equal(uv->name, name) && uv->local == false) {
1014                                 *constant = uv->constant;
1015 
1016                                 return i;
1017                         }
1018                 }
1019 
1020                 return -1;
1021         }
1022 
1023         idx = uc_compiler_resolve_local(compiler->parent, name, constant);
1024 
1025         if (idx > -1) {
1026                 compiler->parent->locals.entries[idx].captured = true;
1027 
1028                 return uc_compiler_add_upval(compiler, idx, true, name, *constant);
1029         }
1030 
1031         idx = uc_compiler_resolve_upval(compiler->parent, name, constant);
1032 
1033         if (idx > -1)
1034                 return uc_compiler_add_upval(compiler, idx, false, name, *constant);
1035 
1036         return -1;
1037 }
1038 
1039 static void
1040 uc_compiler_backpatch(uc_compiler_t *compiler, size_t break_addr, size_t next_addr)
1041 {
1042         uc_patchlist_t *pl = compiler->patchlist;
1043         volatile ssize_t jmpaddr;
1044         size_t i;
1045 
1046         for (i = 0; i < pl->count; i++) {
1047                 jmpaddr = uc_compiler_get_jmpaddr(compiler, pl->entries[i]);
1048 
1049                 switch (jmpaddr) {
1050                 case TK_BREAK:
1051                         /* if we have a break addr, patch instruction */
1052                         if (break_addr) {
1053                                 uc_compiler_set_jmpaddr(compiler, pl->entries[i], break_addr);
1054                                 continue;
1055                         }
1056 
1057                         break;
1058 
1059                 case TK_CONTINUE:
1060                         /* if we have a continue addr, patch instruction */
1061                         if (next_addr) {
1062                                 uc_compiler_set_jmpaddr(compiler, pl->entries[i], next_addr);
1063                                 continue;
1064                         }
1065 
1066                         break;
1067                 }
1068 
1069                 /* there should be no unhandled instructions */
1070                 assert(0);
1071         }
1072 
1073         free(pl->entries);
1074 
1075         compiler->patchlist = pl->parent;
1076 }
1077 
1078 static bool
1079 uc_compiler_check_assignment_lhs(uc_compiler_t *compiler)
1080 {
1081         return (
1082                 compiler->patchlist == NULL ||
1083                 compiler->patchlist->count == 0 ||
1084                 compiler->patchlist->token != TK_EXP
1085         );
1086 }
1087 
1088 static void
1089 uc_compiler_emit_inc_dec(uc_compiler_t *compiler, uc_tokentype_t toktype, bool is_postfix)
1090 {
1091         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
1092         uc_value_t *varname = NULL;
1093         uc_vm_insn_t type;
1094         uint32_t cidx = 0;
1095         int insn;
1096 
1097         /* determine kind of emitted load instruction and operand value (if any) */
1098         type = chunk->entries ? chunk->entries[compiler->last_insn] : 0;
1099 
1100         if (type == I_LVAR || type == I_LLOC || type == I_LUPV) {
1101                 cidx = uc_compiler_get_u32(compiler, compiler->last_insn + 1);
1102 
1103                 if (type == I_LLOC && compiler->locals.entries[cidx].constant)
1104                         varname = compiler->locals.entries[cidx].name;
1105                 else if (type == I_LUPV && compiler->upvals.entries[cidx].constant)
1106                         varname = compiler->upvals.entries[cidx].name;
1107 
1108                 if (varname)
1109                         uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
1110                                 "Invalid increment/decrement of constant '%s'",
1111                                 ucv_string_get(varname));
1112 
1113                 uc_chunk_pop(chunk);
1114                 uc_chunk_pop(chunk);
1115                 uc_chunk_pop(chunk);
1116                 uc_chunk_pop(chunk);
1117                 uc_chunk_pop(chunk);
1118         }
1119 
1120         /* if we're mutating an object or array field, pop the last lval instruction
1121          * to leave object + last field name value on stack */
1122         else if (type == I_LVAL) {
1123                 if (!uc_compiler_check_assignment_lhs(compiler)) {
1124                         uc_compiler_syntax_error(compiler, 0,
1125                                 "Invalid left-hand side expression for increment/decrement");
1126 
1127                         return;
1128                 }
1129 
1130                 uc_chunk_pop(chunk);
1131         }
1132         else {
1133                 uc_compiler_syntax_error(compiler, 0, "Invalid increment/decrement operand");
1134 
1135                 return;
1136         }
1137 
1138         insn = (toktype == TK_INC) ? I_PLUS : I_MINUS;
1139 
1140         /* add / subtract 1 */
1141         uc_compiler_emit_insn(compiler, 0, I_LOAD8);
1142         uc_compiler_emit_u8(compiler, 0, 1);
1143 
1144         /* depending on variable type, emit corresponding increment instruction */
1145         switch (type) {
1146         case I_LVAR:
1147                 uc_compiler_emit_insn(compiler, 0, I_UVAR);
1148                 uc_compiler_emit_u32(compiler, 0, (insn << 24) | cidx);
1149                 break;
1150 
1151         case I_LLOC:
1152                 uc_compiler_emit_insn(compiler, 0, I_ULOC);
1153                 uc_compiler_emit_u32(compiler, 0, (insn << 24) | cidx);
1154                 break;
1155 
1156         case I_LUPV:
1157                 uc_compiler_emit_insn(compiler, 0, I_UUPV);
1158                 uc_compiler_emit_u32(compiler, 0, (insn << 24) | cidx);
1159                 break;
1160 
1161         case I_LVAL:
1162                 uc_compiler_emit_insn(compiler, 0, I_UVAL);
1163                 uc_compiler_emit_u8(compiler, 0, insn);
1164                 break;
1165 
1166         default:
1167                 break;
1168         }
1169 
1170         /* for post increment or decrement, add/subtract 1 to yield final value */
1171         if (is_postfix) {
1172                 uc_compiler_emit_insn(compiler, 0, I_LOAD8);
1173                 uc_compiler_emit_u8(compiler, 0, 1);
1174 
1175                 uc_compiler_emit_insn(compiler, 0, (toktype == TK_INC) ? I_SUB : I_ADD);
1176         }
1177 }
1178 
1179 
1180 static void
1181 uc_compiler_compile_unary(uc_compiler_t *compiler)
1182 {
1183         uc_tokentype_t type = compiler->parser->prev.type;
1184 
1185         uc_compiler_parse_precedence(compiler, P_UNARY);
1186 
1187         switch (type) {
1188         case TK_SUB:
1189                 uc_compiler_emit_insn(compiler, 0, I_MINUS);
1190                 break;
1191 
1192         case TK_ADD:
1193                 uc_compiler_emit_insn(compiler, 0, I_PLUS);
1194                 break;
1195 
1196         case TK_NOT:
1197                 uc_compiler_emit_insn(compiler, 0, I_NOT);
1198                 break;
1199 
1200         case TK_COMPL:
1201                 uc_compiler_emit_insn(compiler, 0, I_COMPL);
1202                 break;
1203 
1204         case TK_INC:
1205         case TK_DEC:
1206                 uc_compiler_emit_inc_dec(compiler, type, false);
1207                 break;
1208 
1209         default:
1210                 return;
1211         }
1212 }
1213 
1214 static void
1215 uc_compiler_compile_binary(uc_compiler_t *compiler)
1216 {
1217         uc_tokentype_t type = compiler->parser->prev.type;
1218 
1219         uc_compiler_parse_precedence(compiler, uc_compiler_parse_rule(type)->precedence + 1);
1220         uc_compiler_emit_insn(compiler, 0, I_BOR + (type - TK_BOR));
1221 }
1222 
1223 static void
1224 uc_compiler_compile_delete(uc_compiler_t *compiler)
1225 {
1226         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
1227         uc_vm_insn_t type;
1228 
1229         uc_compiler_parse_precedence(compiler, P_UNARY);
1230 
1231         type = chunk->entries[compiler->last_insn];
1232 
1233         if (type != I_LVAL)
1234                 uc_compiler_syntax_error(compiler, 0,
1235                         "expecting a property access expression");
1236 
1237         chunk->entries[compiler->last_insn] = I_DELETE;
1238 }
1239 
1240 static uc_vm_insn_t
1241 uc_compiler_emit_variable_rw(uc_compiler_t *compiler, uc_value_t *varname, uc_tokentype_t type)
1242 {
1243         uc_vm_insn_t insn;
1244         uint32_t sub_insn;
1245         bool constant;
1246         ssize_t idx;
1247 
1248         switch (type) {
1249         case TK_ASADD:     sub_insn = I_ADD;     break;
1250         case TK_ASSUB:     sub_insn = I_SUB;     break;
1251         case TK_ASMUL:     sub_insn = I_MUL;     break;
1252         case TK_ASDIV:     sub_insn = I_DIV;     break;
1253         case TK_ASMOD:     sub_insn = I_MOD;     break;
1254         case TK_ASBAND:    sub_insn = I_BAND;    break;
1255         case TK_ASBXOR:    sub_insn = I_BXOR;    break;
1256         case TK_ASBOR:     sub_insn = I_BOR;     break;
1257         case TK_ASLEFT:    sub_insn = I_LSHIFT;  break;
1258         case TK_ASRIGHT:   sub_insn = I_RSHIFT;  break;
1259         case TK_ASEXP:     sub_insn = I_EXP;     break;
1260         default:           sub_insn = 0;         break;
1261         }
1262 
1263         if (!varname) {
1264                 if (sub_insn != 0)
1265                         insn = I_UVAL;
1266                 else if (type != 0 && type != TK_QDOT && type != TK_QLBRACK)
1267                         insn = I_SVAL;
1268                 else
1269                         insn = I_LVAL;
1270 
1271                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, insn);
1272 
1273                 if (sub_insn)
1274                         uc_compiler_emit_u8(compiler, compiler->parser->prev.pos, sub_insn);
1275         }
1276         else if ((idx = uc_compiler_resolve_local(compiler, varname, &constant)) > -1) {
1277                 insn = sub_insn ? I_ULOC : (type ? I_SLOC : I_LLOC);
1278 
1279                 if (insn != I_LLOC && constant)
1280                         uc_compiler_syntax_error(compiler, 0,
1281                                 "Invalid assignment to constant '%s'", ucv_string_get(varname));
1282 
1283                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, insn);
1284                 uc_compiler_emit_u32(compiler, compiler->parser->prev.pos,
1285                         ((sub_insn & 0xff) << 24) | idx);
1286         }
1287         else if ((idx = uc_compiler_resolve_upval(compiler, varname, &constant)) > -1) {
1288                 insn = sub_insn ? I_UUPV : (type ? I_SUPV : I_LUPV);
1289 
1290                 if (insn != I_LUPV && constant)
1291                         uc_compiler_syntax_error(compiler, 0,
1292                                 "Invalid assignment to constant '%s'", ucv_string_get(varname));
1293 
1294                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, insn);
1295                 uc_compiler_emit_u32(compiler, compiler->parser->prev.pos,
1296                         ((sub_insn & 0xff) << 24) | idx);
1297         }
1298         else {
1299                 idx = uc_program_add_constant(compiler->program, varname);
1300                 insn = sub_insn ? I_UVAR : (type ? I_SVAR : I_LVAR);
1301 
1302                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, insn);
1303                 uc_compiler_emit_u32(compiler, compiler->parser->prev.pos,
1304                         ((sub_insn & 0xff) << 24) | idx);
1305         }
1306 
1307         return insn;
1308 }
1309 
1310 static void
1311 uc_compiler_emit_variable_copy(uc_compiler_t *compiler, uc_value_t *var)
1312 {
1313         if (!var) {
1314                 uc_compiler_emit_copy(compiler, 0, 1);
1315                 uc_compiler_emit_copy(compiler, 0, 1);
1316         }
1317 
1318         uc_compiler_emit_variable_rw(compiler, var, 0);
1319 }
1320 
1321 static void
1322 uc_compiler_compile_and(uc_compiler_t *compiler)
1323 {
1324         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
1325         size_t jmpz_off;
1326 
1327         uc_compiler_emit_copy(compiler, 0, 0);
1328         jmpz_off = uc_compiler_emit_jmpz(compiler, 0);
1329         uc_compiler_emit_insn(compiler, 0, I_POP);
1330         uc_compiler_parse_precedence(compiler, P_AND);
1331         uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
1332 }
1333 
1334 static void
1335 uc_compiler_compile_and_assignment(uc_compiler_t *compiler, uc_value_t *var)
1336 {
1337         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
1338         size_t jmpz_off;
1339 
1340         uc_compiler_emit_variable_copy(compiler, var);
1341         uc_compiler_emit_copy(compiler, 0, 0);
1342         jmpz_off = uc_compiler_emit_jmpz(compiler, 0);
1343         uc_compiler_emit_insn(compiler, 0, I_POP);
1344         uc_compiler_parse_precedence(compiler, P_ASSIGN);
1345         uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
1346         uc_compiler_emit_variable_rw(compiler, var, TK_ASSIGN);
1347 }
1348 
1349 static void
1350 uc_compiler_compile_or(uc_compiler_t *compiler)
1351 {
1352         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
1353         size_t jmpz_off, jmp_off;
1354 
1355         uc_compiler_emit_copy(compiler, 0, 0);
1356         jmpz_off = uc_compiler_emit_jmpz(compiler, 0);
1357         jmp_off = uc_compiler_emit_jmp(compiler, 0);
1358         uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
1359         uc_compiler_emit_insn(compiler, 0, I_POP);
1360         uc_compiler_parse_precedence(compiler, P_OR);
1361         uc_compiler_set_jmpaddr(compiler, jmp_off, chunk->count);
1362 }
1363 
1364 static void
1365 uc_compiler_compile_or_assignment(uc_compiler_t *compiler, uc_value_t *var)
1366 {
1367         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
1368         size_t jmpz_off, jmp_off;
1369 
1370         uc_compiler_emit_variable_copy(compiler, var);
1371         jmpz_off = uc_compiler_emit_jmpz(compiler, 0);
1372         uc_compiler_emit_variable_rw(compiler, var, 0);
1373         jmp_off = uc_compiler_emit_jmp(compiler, 0);
1374         uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
1375         uc_compiler_parse_precedence(compiler, P_ASSIGN);
1376         uc_compiler_emit_variable_rw(compiler, var, TK_ASSIGN);
1377         uc_compiler_set_jmpaddr(compiler, jmp_off, chunk->count);
1378 }
1379 
1380 static void
1381 uc_compiler_compile_nullish(uc_compiler_t *compiler)
1382 {
1383         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
1384         size_t jmpz_off, jmp_off;
1385 
1386         uc_compiler_emit_copy(compiler, 0, 0);
1387         uc_compiler_emit_insn(compiler, 0, I_LNULL);
1388         uc_compiler_emit_insn(compiler, 0, I_NES);
1389         jmpz_off = uc_compiler_emit_jmpz(compiler, 0);
1390         jmp_off = uc_compiler_emit_jmp(compiler, 0);
1391         uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
1392         uc_compiler_emit_insn(compiler, 0, I_POP);
1393         uc_compiler_parse_precedence(compiler, P_OR);
1394         uc_compiler_set_jmpaddr(compiler, jmp_off, chunk->count);
1395 }
1396 
1397 static void
1398 uc_compiler_compile_nullish_assignment(uc_compiler_t *compiler, uc_value_t *var)
1399 {
1400         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
1401         size_t jmpz_off, jmp_off;
1402 
1403         uc_compiler_emit_variable_copy(compiler, var);
1404         uc_compiler_emit_insn(compiler, 0, I_LNULL);
1405         uc_compiler_emit_insn(compiler, 0, I_NES);
1406         jmpz_off = uc_compiler_emit_jmpz(compiler, 0);
1407         uc_compiler_emit_variable_rw(compiler, var, 0);
1408         jmp_off = uc_compiler_emit_jmp(compiler, 0);
1409         uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
1410         uc_compiler_parse_precedence(compiler, P_ASSIGN);
1411         uc_compiler_emit_variable_rw(compiler, var, TK_ASSIGN);
1412         uc_compiler_set_jmpaddr(compiler, jmp_off, chunk->count);
1413 }
1414 
1415 static void
1416 uc_compiler_compile_expression(uc_compiler_t *compiler)
1417 {
1418         uc_compiler_parse_precedence(compiler, P_COMMA);
1419 }
1420 
1421 static bool
1422 uc_compiler_compile_assignment(uc_compiler_t *compiler, uc_value_t *var)
1423 {
1424         uc_tokentype_t type = compiler->parser->curr.type;
1425 
1426         if (!uc_compiler_parse_at_assignment_op(compiler))
1427                 return false;
1428 
1429         if (!uc_compiler_check_assignment_lhs(compiler)) {
1430                 uc_compiler_syntax_error(compiler, 0,
1431                         "Invalid left-hand side expression for assignment");
1432 
1433                 return false;
1434         }
1435 
1436         switch (type)
1437         {
1438         case TK_ASNULLISH:
1439                 uc_compiler_parse_advance(compiler);
1440                 uc_compiler_compile_nullish_assignment(compiler, var);
1441                 break;
1442 
1443         case TK_ASOR:
1444                 uc_compiler_parse_advance(compiler);
1445                 uc_compiler_compile_or_assignment(compiler, var);
1446                 break;
1447 
1448         case TK_ASAND:
1449                 uc_compiler_parse_advance(compiler);
1450                 uc_compiler_compile_and_assignment(compiler, var);
1451                 break;
1452 
1453         default:
1454                 uc_compiler_parse_advance(compiler);
1455                 uc_compiler_parse_precedence(compiler, P_ASSIGN);
1456                 uc_compiler_emit_variable_rw(compiler, var, type);
1457                 break;
1458         }
1459 
1460         return true;
1461 }
1462 
1463 static bool
1464 uc_compiler_compile_arrowfn(uc_compiler_t *compiler, uc_value_t *args, bool restarg)
1465 {
1466         uc_tokentype_t last_statement_type = TK_NULL;
1467         bool array = (ucv_type(args) == UC_ARRAY);
1468         uc_compiler_t fncompiler = { 0 };
1469         size_t i, pos, load_off;
1470         uc_function_t *fn;
1471         ssize_t slot;
1472 
1473         if (!uc_compiler_parse_match(compiler, TK_ARROW))
1474                 return false;
1475 
1476         pos = compiler->parser->prev.pos;
1477 
1478         uc_compiler_init(&fncompiler, NULL, uc_compiler_current_source(compiler),
1479                 compiler->parser->prev.pos,
1480                 compiler->program,
1481                 uc_compiler_is_strict(compiler));
1482 
1483         fncompiler.parent = compiler;
1484         fncompiler.parser = compiler->parser;
1485         fncompiler.exprstack = compiler->exprstack;
1486 
1487         fn = (uc_function_t *)fncompiler.function;
1488         fn->arrow = true;
1489         fn->vararg = args ? restarg : false;
1490         fn->nargs = array ? ucv_array_length(args) : !!args;
1491 
1492         uc_compiler_enter_scope(&fncompiler);
1493 
1494         /* declare local variables for arguments */
1495         for (i = 0; i < fn->nargs; i++) {
1496                 slot = uc_compiler_declare_local(&fncompiler,
1497                         array ? ucv_array_get(args, i) : args, false);
1498 
1499                 if (slot != -1)
1500                         uc_compiler_syntax_error(&fncompiler, pos,
1501                                 "Duplicate argument names are not allowed in this context");
1502 
1503                 uc_compiler_initialize_local(&fncompiler);
1504         }
1505 
1506         /* parse and compile body */
1507         if (uc_compiler_parse_match(&fncompiler, TK_LBRACE)) {
1508                 while (!uc_compiler_parse_check(&fncompiler, TK_RBRACE) &&
1509                        !uc_compiler_parse_check(&fncompiler, TK_EOF))
1510                         uc_compiler_compile_declaration(&fncompiler);
1511 
1512                 uc_compiler_parse_consume(&fncompiler, TK_RBRACE);
1513 
1514                 /* emit final return */
1515                 if (last_statement_type != TK_RETURN) {
1516                         uc_compiler_emit_insn(&fncompiler, 0, I_LNULL);
1517                         uc_compiler_emit_insn(&fncompiler, 0, I_RETURN);
1518                 }
1519         }
1520         else {
1521                 uc_compiler_parse_precedence(&fncompiler, P_ASSIGN);
1522                 uc_compiler_emit_insn(&fncompiler, 0, I_RETURN);
1523         }
1524 
1525         /* emit load instruction for function value */
1526         uc_compiler_emit_insn(compiler, pos, I_ARFN);
1527         load_off = uc_compiler_emit_u32(compiler, 0, 0);
1528 
1529         /* encode upvalue information */
1530         for (i = 0; i < fn->nupvals; i++)
1531                 uc_compiler_emit_s32(compiler, 0,
1532                         fncompiler.upvals.entries[i].local
1533                                 ? -(fncompiler.upvals.entries[i].index + 1)
1534                                 : fncompiler.upvals.entries[i].index);
1535 
1536         /* finalize function compiler */
1537         fn = uc_compiler_finish(&fncompiler, TK_RETURN);
1538 
1539         if (fn)
1540                 uc_compiler_set_u32(compiler, load_off,
1541                         uc_program_function_id(compiler->program, fn));
1542 
1543         return true;
1544 }
1545 
1546 static uc_tokentype_t
1547 uc_compiler_compile_var_or_arrowfn(uc_compiler_t *compiler, uc_value_t *name)
1548 {
1549         uc_tokentype_t rv;
1550 
1551         if (uc_compiler_exprstack_is(compiler, F_ASSIGNABLE) && uc_compiler_compile_assignment(compiler, name)) {
1552                 rv = TK_ASSIGN;
1553         }
1554         else if (uc_compiler_compile_arrowfn(compiler, name, false)) {
1555                 rv = TK_ARROW;
1556         }
1557         else {
1558                 uc_compiler_emit_variable_rw(compiler, name, 0);
1559                 rv = TK_LABEL;
1560         }
1561 
1562         return rv;
1563 }
1564 
1565 static void
1566 uc_compiler_compile_paren(uc_compiler_t *compiler)
1567 {
1568         uc_value_t *varnames = NULL, *varname;
1569         bool maybe_arrowfn = false;
1570         bool restarg = false;
1571 
1572         /* First try to parse a complete parameter expression and remember the
1573          * consumed label tokens as we go. */
1574         while (true) {
1575                 if (uc_compiler_parse_check(compiler, TK_LABEL)) {
1576                         if (!varnames)
1577                                 varnames = ucv_array_new(NULL);
1578 
1579                         ucv_array_push(varnames, ucv_get(compiler->parser->curr.uv));
1580 
1581                         /* A subsequent slash cannot be a regular expression literal */
1582                         compiler->parser->lex.no_regexp = true;
1583                         uc_compiler_parse_advance(compiler);
1584                 }
1585                 else if (uc_compiler_parse_match(compiler, TK_ELLIP)) {
1586                         uc_compiler_parse_consume(compiler, TK_LABEL);
1587 
1588                         if (!varnames)
1589                                 varnames = ucv_array_new(NULL);
1590 
1591                         ucv_array_push(varnames, ucv_get(compiler->parser->prev.uv));
1592 
1593                         /* A subsequent slash cannot be a regular expression literal */
1594                         compiler->parser->lex.no_regexp = true;
1595                         uc_compiler_parse_consume(compiler, TK_RPAREN);
1596 
1597                         maybe_arrowfn = true;
1598                         restarg = true;
1599 
1600                         break;
1601                 }
1602                 else if (uc_compiler_parse_check(compiler, TK_COMMA)) {
1603                         /* Reject consecutive commas */
1604                         if (compiler->parser->prev.type == TK_COMMA)
1605                                 uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
1606                                         "Expecting expression");
1607 
1608                         uc_compiler_parse_advance(compiler);
1609 
1610                         continue;
1611                 }
1612                 else {
1613                         maybe_arrowfn = uc_compiler_parse_check(compiler, TK_RPAREN);
1614 
1615                         if (maybe_arrowfn) {
1616                                 /* A subsequent slash cannot be a regular expression literal */
1617                                 compiler->parser->lex.no_regexp = true;
1618                                 uc_compiler_parse_advance(compiler);
1619                         }
1620 
1621                         /* If we encounter a dot, treat potential subsequent keyword as label */
1622                         if (uc_compiler_parse_check(compiler, TK_DOT) ||
1623                             uc_compiler_parse_check(compiler, TK_QDOT))
1624                                 compiler->parser->lex.no_keyword = true;
1625 
1626                         break;
1627                 }
1628         }
1629 
1630         /* The lhs we parsed so far is eligible for an arrow function arg list,
1631          * try to continue compiling into arrow function... */
1632         if (maybe_arrowfn) {
1633                 /* If we can parse the remainder as arrow function, we're done */
1634                 if (uc_compiler_compile_arrowfn(compiler, varnames, restarg))
1635                         goto out;
1636 
1637                 /* ... otherwise disallow the `...` spread operator and empty
1638                  * parenthesized expressions */
1639                 if (restarg || !varnames) {
1640                         uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
1641                                 "Expecting '=>' after parameter list");
1642 
1643                         goto out;
1644                 }
1645         }
1646 
1647         /* If we reach this, the expression we parsed so far cannot be a parameter
1648          * list for an arrow function and we might have consumed one or multiple
1649          * consecutive labels. */
1650         if (varnames) {
1651                 /* Get last variable name */
1652                 varname = ucv_array_get(varnames,
1653                         ucv_array_length(varnames) - 1);
1654 
1655                 /* If we consumed the right paren, the expression is complete and we
1656                  * only need to emit a variable read operation for the last parsed
1657                  * label since previous read operations are shadowed by subsequent ones
1658                  * in comma expressions and since pure variable reads are without
1659                  * side effects. */
1660                 if (maybe_arrowfn) {
1661                         uc_compiler_emit_variable_rw(compiler, varname, 0);
1662 
1663                         goto out;
1664                 }
1665 
1666                 /* ... otherwise if the last token was a label, try continue parsing as
1667                  * assignment or arrow function expression and if that fails, as
1668                  * relational one */
1669                 if (compiler->parser->prev.type == TK_LABEL) {
1670                         uc_compiler_exprstack_push(compiler, TK_LABEL, F_ASSIGNABLE);
1671 
1672                         if (uc_compiler_compile_var_or_arrowfn(compiler, varname) == TK_LABEL) {
1673                                 /* parse operand and rhs */
1674                                 while (P_TERNARY <= uc_compiler_parse_rule(compiler->parser->curr.type)->precedence) {
1675                                         uc_compiler_parse_advance(compiler);
1676                                         uc_compiler_parse_rule(compiler->parser->prev.type)->infix(compiler);
1677                                 }
1678                         }
1679 
1680                         /* If we're not at the end of the expression, we require a comma.
1681                          * Also pop intermediate result in this case. */
1682                         if (!uc_compiler_parse_check(compiler, TK_RPAREN)) {
1683                                 uc_compiler_emit_insn(compiler, 0, I_POP);
1684                                 uc_compiler_parse_consume(compiler, TK_COMMA);
1685                         }
1686 
1687                         uc_compiler_exprstack_pop(compiler);
1688                 }
1689         }
1690 
1691         /* When we reach this point, all already complete expression possibilities
1692          * have been eliminated and we either need to compile the next, non-label
1693          * expression or reached the closing paren. If neither applies, we have a
1694          * syntax error. */
1695         if (!uc_compiler_parse_check(compiler, TK_RPAREN))
1696                 uc_compiler_compile_expression(compiler);
1697 
1698         /* A subsequent slash cannot be a regular expression literal */
1699         compiler->parser->lex.no_regexp = true;
1700 
1701         /* At this point we expect the end of the parenthesized expression, anything
1702          * else is a syntax error */
1703         uc_compiler_parse_consume(compiler, TK_RPAREN);
1704 
1705 out:
1706         ucv_put(varnames);
1707 }
1708 
1709 static void
1710 uc_compiler_compile_call(uc_compiler_t *compiler)
1711 {
1712         bool optional_chaining = (compiler->parser->prev.type == TK_QLPAREN);
1713         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
1714         uc_jmplist_t spreads = { 0 };
1715         uc_vm_insn_t type;
1716         size_t i, nargs = 0;
1717         bool mcall;
1718 
1719         /* determine the kind of the lhs */
1720         type = chunk->entries[compiler->last_insn];
1721         mcall = (type == I_LVAL);
1722 
1723         if (mcall) {
1724                 uc_chunk_pop(chunk);
1725                 uc_compiler_emit_insn(compiler, 0, I_PVAL);
1726         }
1727 
1728         if (optional_chaining)
1729                 uc_compiler_emit_jmpnt(compiler, compiler->parser->prev.pos,
1730                         (1u << UC_CFUNCTION) | (1u << UC_CLOSURE), mcall);
1731 
1732         /* compile arguments */
1733         if (!uc_compiler_parse_check(compiler, TK_RPAREN)) {
1734                 do {
1735                         /* if this is a spread arg, remember the argument index */
1736                         if (uc_compiler_parse_match(compiler, TK_ELLIP))
1737                                 uc_vector_push(&spreads, nargs);
1738 
1739                         /* compile argument expression */
1740                         uc_compiler_parse_precedence(compiler, P_ASSIGN);
1741                         nargs++;
1742                 }
1743                 while (uc_compiler_parse_match(compiler, TK_COMMA));
1744         }
1745 
1746         /* after a function call expression, no regexp literal can follow */
1747         compiler->parser->lex.no_regexp = true;
1748         uc_compiler_parse_consume(compiler, TK_RPAREN);
1749 
1750         /* if lhs is a dot or bracket expression, emit a method call */
1751         uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_CALL);
1752 
1753         if (nargs > 0xffff || spreads.count > 0x7fff)
1754                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
1755                         "Too many function call arguments");
1756 
1757         /* encode ordinary (bits 0..15) and spread argument (bits 16..30) count
1758            as well as method call indication (bit 31) */
1759         uc_compiler_emit_u32(compiler, 0,
1760                 (mcall ? 0x80000000 : 0) | ((spreads.count & 0x7fff) << 16) | nargs);
1761 
1762         /* encode spread arg positions */
1763         for (i = 0; i < spreads.count; i++)
1764                 uc_compiler_emit_u16(compiler, 0, nargs - spreads.entries[i] - 1);
1765 
1766         uc_vector_clear(&spreads);
1767 
1768         compiler->patchlist->depth = uc_compiler_current_chunk(compiler)->count;
1769 }
1770 
1771 static void
1772 uc_compiler_compile_post_inc(uc_compiler_t *compiler)
1773 {
1774         uc_compiler_emit_inc_dec(compiler, compiler->parser->prev.type, true);
1775 }
1776 
1777 static bool
1778 uc_compiler_is_use_strict_pragma(uc_compiler_t *compiler)
1779 {
1780         uc_value_t *v;
1781 
1782         if (uc_compiler_current_chunk(compiler)->count > 0)
1783                 return false;
1784 
1785         if (compiler->parser->lex.block != STATEMENTS)
1786                 return false;
1787 
1788         v = compiler->parser->prev.uv;
1789 
1790         return (strcmp(ucv_string_get(v), "use strict") == 0);
1791 }
1792 
1793 static void
1794 uc_compiler_compile_constant(uc_compiler_t *compiler)
1795 {
1796         uc_function_t *fn;
1797         uint64_t u;
1798 
1799         switch (compiler->parser->prev.type) {
1800         case TK_THIS:
1801                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_LTHIS);
1802                 break;
1803 
1804         case TK_NULL:
1805                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_LNULL);
1806                 break;
1807 
1808         case TK_TRUE:
1809                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_LTRUE);
1810                 break;
1811 
1812         case TK_FALSE:
1813                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_LFALSE);
1814                 break;
1815 
1816         case TK_STRING:
1817                 if (uc_compiler_is_use_strict_pragma(compiler)) {
1818                         fn = (uc_function_t *)compiler->function;
1819                         fn->strict = true;
1820                 }
1821 
1822                 /* fall through */
1823 
1824         case TK_DOUBLE:
1825                 uc_compiler_emit_constant(compiler, compiler->parser->prev.pos, compiler->parser->prev.uv);
1826                 break;
1827 
1828         case TK_REGEXP:
1829                 uc_compiler_emit_regexp(compiler, compiler->parser->prev.pos, compiler->parser->prev.uv);
1830                 break;
1831 
1832         case TK_NUMBER:
1833                 u = ucv_uint64_get(compiler->parser->prev.uv);
1834                 assert(errno == 0);
1835 
1836                 if (u <= 0xff) {
1837                         uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_LOAD8);
1838                         uc_compiler_emit_u8(compiler, compiler->parser->prev.pos, u);
1839                 }
1840                 else if (u <= 0xffff) {
1841                         uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_LOAD16);
1842                         uc_compiler_emit_u16(compiler, compiler->parser->prev.pos, u);
1843                 }
1844                 else if (u <= 0xffffffff) {
1845                         uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_LOAD32);
1846                         uc_compiler_emit_u32(compiler, compiler->parser->prev.pos, u);
1847                 }
1848                 else {
1849                         uc_compiler_emit_constant(compiler, compiler->parser->prev.pos, compiler->parser->prev.uv);
1850                 }
1851 
1852                 break;
1853 
1854         default:
1855                 break;
1856         }
1857 }
1858 
1859 static void
1860 uc_compiler_compile_template(uc_compiler_t *compiler)
1861 {
1862         uc_compiler_emit_constant(compiler, compiler->parser->prev.pos, compiler->parser->prev.uv);
1863 
1864         while (true) {
1865                 if (uc_compiler_parse_match(compiler, TK_TEMPLATE)) {
1866                         uc_compiler_emit_constant(compiler, compiler->parser->prev.pos, compiler->parser->prev.uv);
1867                         uc_compiler_emit_insn(compiler, 0, I_ADD);
1868                 }
1869                 else if (uc_compiler_parse_match(compiler, TK_PLACEH)) {
1870                         uc_compiler_compile_expression(compiler);
1871                         uc_compiler_emit_insn(compiler, 0, I_ADD);
1872                         uc_compiler_parse_consume(compiler, TK_RBRACE);
1873                 }
1874                 else {
1875                         break;
1876                 }
1877         }
1878 }
1879 
1880 static void
1881 uc_compiler_compile_comma(uc_compiler_t *compiler)
1882 {
1883         uc_compiler_emit_insn(compiler, 0, I_POP);
1884         uc_compiler_parse_precedence(compiler, P_ASSIGN);
1885 }
1886 
1887 static void
1888 uc_compiler_compile_labelexpr(uc_compiler_t *compiler)
1889 {
1890         uc_value_t *label = ucv_get(compiler->parser->prev.uv);
1891 
1892         uc_compiler_compile_var_or_arrowfn(compiler, label);
1893         ucv_put(label);
1894 }
1895 
1896 static uc_tokentype_t
1897 uc_compiler_compile_delimitted_block(uc_compiler_t *compiler, uc_tokentype_t endtype)
1898 {
1899         uc_tokentype_t last_statement_type = TK_NULL;
1900 
1901         while (!uc_compiler_parse_check(compiler, endtype) &&
1902                !uc_compiler_parse_check(compiler, TK_EOF))
1903                 last_statement_type = uc_compiler_compile_declaration(compiler);
1904 
1905         return uc_compiler_parse_check(compiler, endtype) ? last_statement_type : TK_EOF;
1906 }
1907 
1908 static void
1909 uc_compiler_compile_funcexpr_common(uc_compiler_t *compiler, bool require_name)
1910 {
1911         uc_tokentype_t last_statement_type = TK_NULL;
1912         uc_compiler_t fncompiler = { 0 };
1913         uc_value_t *name = NULL;
1914         ssize_t slot = -1, pos;
1915         uc_tokentype_t type;
1916         size_t i, load_off;
1917         uc_function_t *fn;
1918 
1919         pos = compiler->parser->prev.pos;
1920         type = compiler->parser->prev.type;
1921 
1922         if (uc_compiler_parse_match(compiler, TK_LABEL)) {
1923                 name = compiler->parser->prev.uv;
1924 
1925                 if (require_name && uc_compiler_parse_check(compiler, TK_SCOL)) {
1926                         slot = uc_compiler_resolve_funcstub(compiler, name);
1927 
1928                         if (slot > -1) {
1929                                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
1930                                         "Function '%s' redeclared", ucv_string_get(name));
1931 
1932                                 return;
1933                         }
1934 
1935                         slot = uc_compiler_declare_local(compiler, name, true);
1936 
1937                         if (slot > -1) {
1938                                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
1939                                         "Variable '%s' redeclared", ucv_string_get(name));
1940 
1941                                 return;
1942                         }
1943 
1944                         compiler->locals.entries[compiler->locals.count - 1].funcstub = true;
1945                         uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_LNULL);
1946                         uc_compiler_initialize_local(compiler);
1947                         uc_compiler_parse_consume(compiler, TK_SCOL);
1948 
1949                         return;
1950                 }
1951 
1952                 slot = uc_compiler_resolve_funcstub(compiler, name);
1953 
1954                 if (slot > -1) {
1955                         compiler->locals.entries[slot].funcstub = false;
1956                 }
1957                 else {
1958                         slot = uc_compiler_declare_local(compiler, name, false);
1959 
1960                         if (slot == -1)
1961                                 uc_compiler_initialize_local(compiler);
1962                         else if (compiler->locals.entries[slot].constant)
1963                                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
1964                                         "Redeclaration of constant '%s'",
1965                                         ucv_string_get(name));
1966                 }
1967         }
1968         else if (require_name) {
1969                 uc_compiler_syntax_error(compiler, compiler->parser->curr.pos, "Expecting function name");
1970         }
1971 
1972         uc_compiler_init(&fncompiler,
1973                 name ? ucv_string_get(name) : NULL,
1974                 uc_compiler_current_source(compiler),
1975                 compiler->parser->prev.pos,
1976                 compiler->program,
1977                 uc_compiler_is_strict(compiler));
1978 
1979         fncompiler.parent = compiler;
1980         fncompiler.parser = compiler->parser;
1981         fncompiler.exprstack = compiler->exprstack;
1982         fn = (uc_function_t *)fncompiler.function;
1983 
1984         uc_compiler_parse_consume(&fncompiler, TK_LPAREN);
1985 
1986         uc_compiler_enter_scope(&fncompiler);
1987 
1988         /* compile argument specification */
1989         while (true) {
1990                 if (uc_compiler_parse_check(&fncompiler, TK_RPAREN))
1991                         break;
1992 
1993                 if (uc_compiler_parse_match(&fncompiler, TK_ELLIP))
1994                         fn->vararg = true;
1995 
1996                 if (uc_compiler_parse_match(&fncompiler, TK_LABEL)) {
1997                         fn->nargs++;
1998 
1999                         uc_compiler_declare_local(&fncompiler, fncompiler.parser->prev.uv, false);
2000                         uc_compiler_initialize_local(&fncompiler);
2001 
2002                         if (fn->vararg ||
2003                             !uc_compiler_parse_match(&fncompiler, TK_COMMA))
2004                                 break;
2005                 }
2006                 else {
2007                         uc_compiler_syntax_error(&fncompiler, fncompiler.parser->curr.pos,
2008                                 "Expecting Label");
2009 
2010                         return;
2011                 }
2012         }
2013 
2014         uc_compiler_parse_consume(&fncompiler, TK_RPAREN);
2015 
2016         /* parse and compile function body */
2017         if (uc_compiler_parse_match(&fncompiler, TK_COLON)) {
2018                 last_statement_type = uc_compiler_compile_delimitted_block(&fncompiler, TK_ENDFUNC);
2019                 uc_compiler_parse_consume(&fncompiler, TK_ENDFUNC);
2020         }
2021         else if (uc_compiler_parse_match(&fncompiler, TK_LBRACE)) {
2022                 last_statement_type = uc_compiler_compile_delimitted_block(&fncompiler, TK_RBRACE);
2023                 uc_compiler_parse_consume(&fncompiler, TK_RBRACE);
2024         }
2025         else {
2026                 uc_compiler_syntax_error(&fncompiler, fncompiler.parser->curr.pos,
2027                         "Expecting '{' or ':' after function parameters");
2028         }
2029 
2030         /* emit load instruction for function value */
2031         uc_compiler_emit_insn(compiler, pos, (type == TK_ARROW) ? I_ARFN : I_CLFN);
2032         load_off = uc_compiler_emit_u32(compiler, 0, 0);
2033 
2034         /* encode upvalue information */
2035         for (i = 0; i < fn->nupvals; i++)
2036                 uc_compiler_emit_s32(compiler, 0,
2037                         fncompiler.upvals.entries[i].local
2038                                 ? -(fncompiler.upvals.entries[i].index + 1)
2039                                 : fncompiler.upvals.entries[i].index);
2040 
2041         /* finalize function compiler */
2042         fn = uc_compiler_finish(&fncompiler, last_statement_type);
2043 
2044         if (fn)
2045                 uc_compiler_set_u32(compiler, load_off,
2046                         uc_program_function_id(compiler->program, fn));
2047 
2048         /* if a local variable of the same name already existed, overwrite its value
2049          * with the compiled function here */
2050         if (slot != -1) {
2051                 uc_compiler_emit_insn(compiler, 0, I_SLOC);
2052                 uc_compiler_emit_u32(compiler, 0, slot);
2053                 uc_compiler_emit_insn(compiler, 0, I_POP);
2054         }
2055 }
2056 
2057 static void
2058 uc_compiler_compile_funcexpr(uc_compiler_t *compiler)
2059 {
2060         return uc_compiler_compile_funcexpr_common(compiler, false);
2061 }
2062 
2063 static void
2064 uc_compiler_compile_funcdecl(uc_compiler_t *compiler)
2065 {
2066         return uc_compiler_compile_funcexpr_common(compiler, true);
2067 }
2068 
2069 static void
2070 uc_compiler_compile_dot(uc_compiler_t *compiler)
2071 {
2072         bool optional_chaining = (compiler->parser->prev.type == TK_QDOT);
2073 
2074         /* no regexp literal possible after property access */
2075         compiler->parser->lex.no_regexp = true;
2076 
2077         if (optional_chaining)
2078                 uc_compiler_emit_jmpnt(compiler, compiler->parser->prev.pos,
2079                         (1u << UC_ARRAY) | (1u << UC_OBJECT) | (1u << UC_RESOURCE), 0);
2080 
2081         /* parse label lhs */
2082         uc_compiler_parse_consume(compiler, TK_LABEL);
2083         uc_compiler_emit_constant(compiler, compiler->parser->prev.pos, compiler->parser->prev.uv);
2084 
2085         /* depending on context, compile into I_UVAL, I_SVAL or I_LVAL operation */
2086         if (!uc_compiler_exprstack_is(compiler, F_ASSIGNABLE) || !uc_compiler_compile_assignment(compiler, NULL))
2087                 uc_compiler_emit_variable_rw(compiler, NULL, optional_chaining ? TK_QDOT : 0);
2088 
2089         compiler->patchlist->depth = uc_compiler_current_chunk(compiler)->count;
2090 }
2091 
2092 static void
2093 uc_compiler_compile_subscript(uc_compiler_t *compiler)
2094 {
2095         bool optional_chaining = (compiler->parser->prev.type == TK_QLBRACK);
2096 
2097         if (optional_chaining)
2098                 uc_compiler_emit_jmpnt(compiler, compiler->parser->prev.pos,
2099                         (1u << UC_ARRAY) | (1u << UC_OBJECT) | (1u << UC_RESOURCE), 0);
2100 
2101         /* compile lhs */
2102         uc_compiler_compile_expression(compiler);
2103 
2104         /* no regexp literal possible after computed property access */
2105         compiler->parser->lex.no_regexp = true;
2106         uc_compiler_parse_consume(compiler, TK_RBRACK);
2107 
2108         /* depending on context, compile into I_UVAL, I_SVAL or I_LVAL operation */
2109         if (!uc_compiler_exprstack_is(compiler, F_ASSIGNABLE) || !uc_compiler_compile_assignment(compiler, NULL))
2110                 uc_compiler_emit_variable_rw(compiler, NULL, optional_chaining ? TK_QLBRACK : 0);
2111 
2112         compiler->patchlist->depth = uc_compiler_current_chunk(compiler)->count;
2113 }
2114 
2115 static void
2116 uc_compiler_compile_ternary(uc_compiler_t *compiler)
2117 {
2118         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
2119         size_t jmpz_off, jmp_off;
2120 
2121         /* jump to false branch */
2122         jmpz_off = uc_compiler_emit_jmpz(compiler, 0);
2123 
2124         /* compile true branch */
2125         uc_compiler_parse_precedence(compiler, P_ASSIGN);
2126 
2127         /* jump after false branch */
2128         jmp_off = uc_compiler_emit_jmp(compiler, 0);
2129 
2130         uc_compiler_parse_consume(compiler, TK_COLON);
2131 
2132         /* compile false branch */
2133         uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
2134         uc_compiler_parse_precedence(compiler, P_TERNARY);
2135         uc_compiler_set_jmpaddr(compiler, jmp_off, chunk->count);
2136 }
2137 
2138 static void
2139 uc_compiler_compile_array(uc_compiler_t *compiler)
2140 {
2141         size_t hint_off, hint_count = 0, len = 0;
2142 
2143         /* create empty array on stack */
2144         uc_compiler_emit_insn(compiler, 0, I_NARR);
2145         hint_off = uc_compiler_emit_u32(compiler, 0, 0);
2146 
2147         /* parse initializer values */
2148         do {
2149                 if (uc_compiler_parse_check(compiler, TK_RBRACK)) {
2150                         break;
2151                 }
2152                 else if (uc_compiler_parse_match(compiler, TK_ELLIP)) {
2153                         /* push items on stack so far... */
2154                         if (len > 0) {
2155                                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_PARR);
2156                                 uc_compiler_emit_u32(compiler, 0, len);
2157                                 len = 0;
2158                         }
2159 
2160                         /* compile spread value expression */
2161                         uc_compiler_parse_precedence(compiler, P_ASSIGN);
2162 
2163                         /* emit merge operation */
2164                         uc_compiler_emit_insn(compiler, 0, I_MARR);
2165                 }
2166                 else {
2167                         /* push items on stack so far... */
2168                         if (len >= 0xffffffff) {
2169                                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_PARR);
2170                                 uc_compiler_emit_u32(compiler, 0, len);
2171                                 len = 0;
2172                         }
2173 
2174                         /* compile item value expression */
2175                         uc_compiler_parse_precedence(compiler, P_ASSIGN);
2176 
2177                         hint_count++;
2178                         len++;
2179                 }
2180         }
2181         while (uc_compiler_parse_match(compiler, TK_COMMA));
2182 
2183         /* no regexp literal possible after array literal */
2184         compiler->parser->lex.no_regexp = true;
2185         uc_compiler_parse_consume(compiler, TK_RBRACK);
2186 
2187         /* push items on stack */
2188         if (len > 0) {
2189                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_PARR);
2190                 uc_compiler_emit_u32(compiler, 0, len);
2191         }
2192 
2193         /* set initial size hint */
2194         uc_compiler_set_u32(compiler, hint_off, hint_count);
2195 }
2196 
2197 static void
2198 uc_compiler_compile_object(uc_compiler_t *compiler)
2199 {
2200         size_t hint_off, hint_count = 0, len = 0;
2201 
2202         /* create empty object on stack */
2203         uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_NOBJ);
2204         hint_off = uc_compiler_emit_u32(compiler, 0, 0);
2205 
2206         /* parse initializer values */
2207         do {
2208                 /* End of object literal */
2209                 if (uc_compiler_parse_check(compiler, TK_RBRACE))
2210                         break;
2211 
2212                 /* Spread operator */
2213                 if (uc_compiler_parse_match(compiler, TK_ELLIP)) {
2214                         /* set items on stack so far... */
2215                         if (len > 0) {
2216                                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_SOBJ);
2217                                 uc_compiler_emit_u32(compiler, 0, len);
2218                                 len = 0;
2219                         }
2220 
2221                         /* compile spread value expression */
2222                         uc_compiler_parse_precedence(compiler, P_ASSIGN);
2223 
2224                         /* emit merge operation */
2225                         uc_compiler_emit_insn(compiler, 0, I_MOBJ);
2226 
2227                         compiler->parser->lex.no_keyword = true;
2228                         continue;
2229                 }
2230 
2231                 /* Computed property name */
2232                 if (uc_compiler_parse_match(compiler, TK_LBRACK)) {
2233                         /* parse property name expression */
2234                         uc_compiler_parse_precedence(compiler, P_ASSIGN);
2235 
2236                         /* consume closing bracket and colon */
2237                         uc_compiler_parse_consume(compiler, TK_RBRACK);
2238                         uc_compiler_parse_consume(compiler, TK_COLON);
2239 
2240                         /* parse value expression */
2241                         uc_compiler_parse_precedence(compiler, P_ASSIGN);
2242                 }
2243 
2244                 /* Property/value tuple or property shorthand */
2245                 else {
2246                         /* parse key expression */
2247                         if (!uc_compiler_parse_match(compiler, TK_LABEL) &&
2248                             !uc_compiler_parse_match(compiler, TK_STRING))
2249                                 uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
2250                                         "Expecting label");
2251 
2252                         /* load label */
2253                         uc_compiler_emit_constant(compiler, compiler->parser->prev.pos,
2254                                 compiler->parser->prev.uv);
2255 
2256                         /* If the property name is a plain label followed by a comma or
2257                          * closing curly brace, treat it as ES2015 property shorthand
2258                          * notation... */
2259                         if (compiler->parser->prev.type == TK_LABEL &&
2260                             (uc_compiler_parse_check(compiler, TK_COMMA) ||
2261                              uc_compiler_parse_check(compiler, TK_RBRACE))) {
2262                                 /* disallow keywords in this case */
2263                                 if (uc_lexer_is_keyword(compiler->parser->prev.uv))
2264                                         uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
2265                                                 "Invalid identifier");
2266 
2267                                 uc_compiler_emit_variable_rw(compiler,
2268                                         compiler->parser->prev.uv, 0);
2269                         }
2270 
2271                         /* ... otherwise treat it as ordinary `key: value` tuple */
2272                         else {
2273                                 uc_compiler_parse_consume(compiler, TK_COLON);
2274 
2275                                 /* parse value expression */
2276                                 uc_compiler_parse_precedence(compiler, P_ASSIGN);
2277                         }
2278                 }
2279 
2280                 /* set items on stack so far... */
2281                 if (len >= 0xfffffffe) {
2282                         uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_SOBJ);
2283                         uc_compiler_emit_u32(compiler, 0, len);
2284                         len = 0;
2285                 }
2286 
2287                 hint_count += 2;
2288                 len += 2;
2289 
2290                 compiler->parser->lex.no_keyword = true;
2291         }
2292         while (uc_compiler_parse_match(compiler, TK_COMMA));
2293 
2294         /* no regexp literal possible after object literal */
2295         compiler->parser->lex.no_regexp = true;
2296         uc_compiler_parse_consume(compiler, TK_RBRACE);
2297 
2298         /* set items on stack */
2299         if (len > 0) {
2300                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_SOBJ);
2301                 uc_compiler_emit_u32(compiler, 0, len);
2302         }
2303 
2304         /* set initial size hint */
2305         uc_compiler_set_u32(compiler, hint_off, hint_count);
2306 }
2307 
2308 
2309 static void
2310 uc_compiler_declare_local_null(uc_compiler_t *compiler, size_t srcpos, uc_value_t *varname)
2311 {
2312         ssize_t existing_slot = uc_compiler_declare_local(compiler, varname, false);
2313 
2314         uc_compiler_emit_insn(compiler, srcpos, I_LNULL);
2315 
2316         if (existing_slot == -1) {
2317                 uc_compiler_initialize_local(compiler);
2318         }
2319         else {
2320                 uc_compiler_emit_insn(compiler, 0, I_SLOC);
2321                 uc_compiler_emit_u32(compiler, 0, existing_slot);
2322                 uc_compiler_emit_insn(compiler, 0, I_POP);
2323         }
2324 }
2325 
2326 static size_t
2327 uc_compiler_declare_internal(uc_compiler_t *compiler, size_t srcpos, const char *name)
2328 {
2329         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
2330         uc_locals_t *locals = &compiler->locals;
2331 
2332         uc_vector_push(locals, {
2333                 .name = ucv_string_new(name),
2334                 .depth = compiler->scope_depth,
2335                 .captured = false,
2336                 .from = chunk->count
2337         });
2338 
2339         return locals->count - 1;
2340 }
2341 
2342 static void
2343 uc_compiler_compile_declexpr(uc_compiler_t *compiler, bool constant)
2344 {
2345         ssize_t slot;
2346 
2347         do {
2348                 /* parse variable name */
2349                 if (!uc_compiler_parse_match(compiler, TK_LABEL)) {
2350                         uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
2351                                 "Expecting variable name");
2352 
2353                         return;
2354                 }
2355 
2356                 /* declare local variable */
2357                 slot = uc_compiler_declare_local(compiler, compiler->parser->prev.uv, constant);
2358 
2359                 /* if followed by '=', parse initializer expression */
2360                 if (uc_compiler_parse_match(compiler, TK_ASSIGN))
2361                         uc_compiler_parse_precedence(compiler, P_ASSIGN);
2362                 /* otherwise, for writable variables, load implicit null */
2363                 else if (!constant)
2364                         uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_LNULL);
2365                 /* for constant variables, a missing initializer is a syntax error */
2366                 else
2367                         uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
2368                                 "Expecting initializer expression");
2369 
2370                 /* initialize local */
2371                 if (slot == -1) {
2372                         uc_compiler_initialize_local(compiler);
2373                 }
2374                 /* if the variable was redeclared, overwrite it */
2375                 else {
2376                         uc_compiler_emit_insn(compiler, 0, I_SLOC);
2377                         uc_compiler_emit_u32(compiler, 0, slot);
2378                         uc_compiler_emit_insn(compiler, 0, I_POP);
2379                 }
2380         }
2381         while (uc_compiler_parse_match(compiler, TK_COMMA));
2382 }
2383 
2384 static void
2385 uc_compiler_compile_local(uc_compiler_t *compiler)
2386 {
2387         uc_compiler_compile_declexpr(compiler, false);
2388         uc_compiler_parse_consume(compiler, TK_SCOL);
2389 }
2390 
2391 static void
2392 uc_compiler_compile_const(uc_compiler_t *compiler)
2393 {
2394         uc_compiler_compile_declexpr(compiler, true);
2395         uc_compiler_parse_consume(compiler, TK_SCOL);
2396 }
2397 
2398 static uc_tokentype_t
2399 uc_compiler_compile_altifblock(uc_compiler_t *compiler)
2400 {
2401         uc_compiler_enter_scope(compiler);
2402 
2403         while (true) {
2404                 switch (compiler->parser->curr.type) {
2405                 case TK_ELIF:
2406                 case TK_ELSE:
2407                 case TK_ENDIF:
2408                 case TK_EOF:
2409                         uc_compiler_leave_scope(compiler);
2410 
2411                         return compiler->parser->curr.type;
2412 
2413                 default:
2414                         uc_compiler_compile_declaration(compiler);
2415                         break;
2416                 }
2417         }
2418 
2419         return 0;
2420 }
2421 
2422 static void
2423 uc_compiler_compile_if(uc_compiler_t *compiler)
2424 {
2425         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
2426         size_t jmpz_off, jmp_off, i;
2427         bool expect_endif = false;
2428         uc_jmplist_t elifs = { 0 };
2429         uc_tokentype_t type;
2430 
2431         /* parse & compile condition expression */
2432         uc_compiler_parse_consume(compiler, TK_LPAREN);
2433         uc_compiler_compile_expression(compiler);
2434         uc_compiler_parse_consume(compiler, TK_RPAREN);
2435 
2436         /* conditional jump to else/elif branch */
2437         jmpz_off = uc_compiler_emit_jmpz(compiler, 0);
2438 
2439         if (uc_compiler_parse_match(compiler, TK_COLON)) {
2440                 compiler->exprstack->flags |= F_ALTBLOCKMODE;
2441 
2442                 while (true) {
2443                         /* compile elsif or else branch */
2444                         type = uc_compiler_compile_altifblock(compiler);
2445 
2446                         /* we just compiled an elsif block */
2447                         if (!expect_endif && type == TK_ELIF) {
2448                                 /* emit jump to skip to the end */
2449                                 uc_vector_push(&elifs, uc_compiler_emit_jmp(compiler, 0));
2450 
2451                                 /* point previous conditional jump to beginning of branch */
2452                                 uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
2453 
2454                                 /* parse & compile elsif condition */
2455                                 uc_compiler_parse_advance(compiler);
2456                                 uc_compiler_parse_consume(compiler, TK_LPAREN);
2457                                 uc_compiler_compile_expression(compiler);
2458                                 uc_compiler_parse_consume(compiler, TK_RPAREN);
2459                                 uc_compiler_parse_consume(compiler, TK_COLON);
2460 
2461                                 /* conditional jump to else/elif branch */
2462                                 jmpz_off = uc_compiler_emit_jmpz(compiler, 0);
2463                         }
2464                         else if (!expect_endif && type == TK_ELSE) {
2465                                 /* emit jump to skip to the end */
2466                                 uc_vector_push(&elifs, uc_compiler_emit_jmp(compiler, 0));
2467 
2468                                 /* point previous conditional jump to beginning of branch */
2469                                 uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
2470                                 jmpz_off = 0;
2471 
2472                                 /* skip "else" keyword */
2473                                 uc_compiler_parse_advance(compiler);
2474 
2475                                 expect_endif = true;
2476                         }
2477                         else if (type == TK_ENDIF) {
2478                                 /* if no else clause, point previous conditional jump after block */
2479                                 if (jmpz_off)
2480                                         uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
2481 
2482                                 /* patch the elif branch jumps to point here after the else */
2483                                 for (i = 0; i < elifs.count; i++)
2484                                         uc_compiler_set_jmpaddr(compiler, elifs.entries[i],
2485                                                 chunk->count);
2486 
2487                                 /* skip the "endif" keyword */
2488                                 uc_compiler_parse_advance(compiler);
2489                                 break;
2490                         }
2491                         else {
2492                                 uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
2493                                         expect_endif
2494                                                 ? "Expecting 'endif'"
2495                                                 : "Expecting 'elif', 'else' or 'endif'");
2496 
2497                                 break;
2498                         }
2499                 }
2500 
2501                 uc_vector_clear(&elifs);
2502         }
2503         else {
2504                 /* compile true branch */
2505                 uc_compiler_compile_statement(compiler);
2506 
2507                 /* ... when present, handle false branch */
2508                 if (uc_compiler_parse_match(compiler, TK_ELSE)) {
2509                         /* jump to skip else branch */
2510                         jmp_off = uc_compiler_emit_jmp(compiler, 0);
2511 
2512                         /* set conditional jump address */
2513                         uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
2514 
2515                         /* compile false branch */
2516                         uc_compiler_compile_statement(compiler);
2517 
2518                         /* set else skip jump address */
2519                         uc_compiler_set_jmpaddr(compiler, jmp_off, chunk->count);
2520                 }
2521                 /* ... otherwise point the conditional jump after the true branch */
2522                 else {
2523                         uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
2524                 }
2525         }
2526 }
2527 
2528 static void
2529 uc_compiler_compile_while(uc_compiler_t *compiler)
2530 {
2531         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
2532         uc_patchlist_t p = { .depth = compiler->scope_depth, .token = TK_WHILE };
2533         size_t cond_off, jmpz_off, end_off;
2534 
2535         p.parent = compiler->patchlist;
2536         compiler->patchlist = &p;
2537 
2538         cond_off = chunk->count;
2539 
2540         /* parse & compile loop condition */
2541         uc_compiler_parse_consume(compiler, TK_LPAREN);
2542         uc_compiler_compile_expression(compiler);
2543         uc_compiler_parse_consume(compiler, TK_RPAREN);
2544 
2545         /* conditional jump to end */
2546         jmpz_off = uc_compiler_emit_jmpz(compiler, 0);
2547 
2548         /* compile loop body */
2549         if (uc_compiler_parse_match(compiler, TK_COLON)) {
2550                 uc_compiler_enter_scope(compiler);
2551 
2552                 if (uc_compiler_compile_delimitted_block(compiler, TK_ENDWHILE) == TK_EOF)
2553                         uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
2554                                 "Expecting 'endwhile'");
2555                 else
2556                         uc_compiler_parse_advance(compiler);
2557 
2558                 uc_compiler_leave_scope(compiler);
2559         }
2560         else {
2561                 uc_compiler_compile_statement(compiler);
2562         }
2563 
2564         end_off = chunk->count;
2565 
2566         /* jump back to condition */
2567         uc_compiler_emit_jmp_dest(compiler, 0, cond_off);
2568 
2569         /* set conditional jump target */
2570         uc_compiler_set_jmpaddr(compiler, jmpz_off, chunk->count);
2571 
2572         /* patch up break/continue */
2573         uc_compiler_backpatch(compiler, chunk->count, end_off);
2574 }
2575 
2576 static void
2577 uc_compiler_compile_for_in(uc_compiler_t *compiler, bool local, uc_token_t *kvar, uc_token_t *vvar)
2578 {
2579         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
2580         uc_patchlist_t p = { .depth = compiler->scope_depth + 1, .token = TK_FOR };
2581         size_t skip_jmp, test_jmp, key_slot, val_slot;
2582 
2583         p.parent = compiler->patchlist;
2584         compiler->patchlist = &p;
2585 
2586         uc_compiler_enter_scope(compiler);
2587 
2588         /* declare internal loop variables */
2589         uc_compiler_emit_insn(compiler, 0, I_LNULL);
2590         key_slot = uc_compiler_declare_internal(compiler, 0, "(for in key)");
2591 
2592         uc_compiler_emit_insn(compiler, 0, I_LNULL);
2593         val_slot = uc_compiler_declare_internal(compiler, 0, "(for in value)");
2594 
2595         /* declare loop variables */
2596         if (local) {
2597                 uc_compiler_declare_local_null(compiler, kvar->pos, kvar->uv);
2598 
2599                 if (vvar)
2600                         uc_compiler_declare_local_null(compiler, vvar->pos, vvar->uv);
2601         }
2602 
2603         /* value to iterate */
2604         uc_compiler_compile_expression(compiler);
2605         uc_compiler_parse_consume(compiler, TK_RPAREN);
2606         uc_compiler_emit_insn(compiler, 0, I_SLOC);
2607         uc_compiler_emit_u32(compiler, 0, val_slot);
2608 
2609         /* initial key value */
2610         uc_compiler_emit_insn(compiler, 0, I_LNULL);
2611         uc_compiler_emit_insn(compiler, 0, I_SLOC);
2612         uc_compiler_emit_u32(compiler, 0, key_slot);
2613 
2614         /* jump over variable read for first cycle */
2615         skip_jmp = uc_compiler_emit_jmp(compiler, 0);
2616 
2617         /* read value */
2618         uc_compiler_emit_insn(compiler, 0, I_LLOC);
2619         uc_compiler_emit_u32(compiler, 0, val_slot);
2620 
2621         /* read key */
2622         uc_compiler_emit_insn(compiler, 0, I_LLOC);
2623         uc_compiler_emit_u32(compiler, 0, key_slot);
2624 
2625         /* backpatch skip jump */
2626         uc_compiler_set_jmpaddr(compiler, skip_jmp, chunk->count);
2627 
2628         /* load loop variable and get next key from object */
2629         uc_compiler_emit_insn(compiler, 0, vvar ? I_NEXTKV : I_NEXTK);
2630 
2631         /* set internal key variable */
2632         uc_compiler_emit_insn(compiler, 0, I_SLOC);
2633         uc_compiler_emit_u32(compiler, 0, key_slot);
2634 
2635         /* test for != null */
2636         uc_compiler_emit_insn(compiler, 0, I_LNULL);
2637         uc_compiler_emit_insn(compiler, 0, I_NES);
2638 
2639         /* jump after loop body if no next key */
2640         test_jmp = uc_compiler_emit_jmpz(compiler, 0);
2641 
2642         /* set key and value variables */
2643         if (vvar) {
2644                 uc_compiler_emit_variable_rw(compiler, vvar->uv, TK_ASSIGN);
2645                 uc_compiler_emit_insn(compiler, 0, I_POP);
2646         }
2647 
2648         /* set key variable */
2649         uc_compiler_emit_variable_rw(compiler, kvar->uv, TK_ASSIGN);
2650         uc_compiler_emit_insn(compiler, 0, I_POP);
2651 
2652         /* compile loop body */
2653         if (uc_compiler_parse_match(compiler, TK_COLON)) {
2654                 uc_compiler_enter_scope(compiler);
2655 
2656                 if (uc_compiler_compile_delimitted_block(compiler, TK_ENDFOR) == TK_EOF)
2657                         uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
2658                                 "Expecting 'endfor'");
2659                 else
2660                         uc_compiler_parse_advance(compiler);
2661 
2662                 uc_compiler_leave_scope(compiler);
2663         }
2664         else {
2665                 uc_compiler_compile_statement(compiler);
2666         }
2667 
2668         /* jump back to retrieve next key */
2669         uc_compiler_emit_jmp_dest(compiler, 0, skip_jmp + 5);
2670 
2671         /* back patch conditional jump */
2672         uc_compiler_set_jmpaddr(compiler, test_jmp, chunk->count);
2673 
2674         /* pop loop variables */
2675         uc_compiler_emit_insn(compiler, 0, I_POP);
2676 
2677         if (vvar)
2678                 uc_compiler_emit_insn(compiler, 0, I_POP);
2679 
2680         /* patch up break/continue */
2681         uc_compiler_backpatch(compiler, chunk->count, skip_jmp + 5);
2682 
2683         uc_compiler_leave_scope(compiler);
2684 }
2685 
2686 static void
2687 uc_compiler_compile_for_count(uc_compiler_t *compiler, bool local, uc_token_t *var)
2688 {
2689         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
2690         size_t test_off = 0, incr_off, skip_off, cond_off = 0;
2691         uc_patchlist_t p = { .depth = compiler->scope_depth + 1, .token = TK_FOR };
2692 
2693         p.parent = compiler->patchlist;
2694         compiler->patchlist = &p;
2695 
2696         uc_compiler_enter_scope(compiler);
2697 
2698         /* Initializer ---------------------------------------------------------- */
2699 
2700         /* If we parsed at least one label, try continue parsing as variable
2701          * expression... */
2702         if (var) {
2703                 /* We parsed a `local x` or `local x, y` expression, so (re)declare
2704                  * last label as local initializer variable */
2705                 if (local)
2706                         uc_compiler_declare_local_null(compiler, var->pos, var->uv);
2707 
2708                 uc_compiler_exprstack_push(compiler, TK_FOR, F_ASSIGNABLE);
2709 
2710                 uc_compiler_compile_labelexpr(compiler);
2711                 uc_compiler_emit_insn(compiler, 0, I_POP);
2712 
2713                 /* If followed by a comma, continue parsing expression */
2714                 if (uc_compiler_parse_match(compiler, TK_COMMA)) {
2715                         /* Is a continuation of a declaration list... */
2716                         if (local) {
2717                                 uc_compiler_compile_declexpr(compiler, false);
2718                         }
2719                         /* ... otherwise an unrelated expression */
2720                         else {
2721                                 uc_compiler_compile_expression(compiler);
2722                                 uc_compiler_emit_insn(compiler, 0, I_POP);
2723                         }
2724                 }
2725 
2726                 uc_compiler_exprstack_pop(compiler);
2727         }
2728         /* ... otherwise try parsing an entire expression (which might be absent) */
2729         else if (!uc_compiler_parse_check(compiler, TK_SCOL)) {
2730                 uc_compiler_compile_expression(compiler);
2731                 uc_compiler_emit_insn(compiler, 0, I_POP);
2732         }
2733 
2734         uc_compiler_parse_consume(compiler, TK_SCOL);
2735 
2736 
2737         /* Condition ------------------------------------------------------------ */
2738         if (!uc_compiler_parse_check(compiler, TK_SCOL)) {
2739                 cond_off = chunk->count;
2740 
2741                 uc_compiler_compile_expression(compiler);
2742 
2743                 test_off = uc_compiler_emit_jmpz(compiler, 0);
2744         }
2745 
2746         uc_compiler_parse_consume(compiler, TK_SCOL);
2747 
2748         /* jump over incrementer */
2749         skip_off = uc_compiler_emit_jmp(compiler, 0);
2750 
2751 
2752         /* Incrementer ---------------------------------------------------------- */
2753         incr_off = chunk->count;
2754 
2755         if (!uc_compiler_parse_check(compiler, TK_RPAREN)) {
2756                 uc_compiler_compile_expression(compiler);
2757                 uc_compiler_emit_insn(compiler, 0, I_POP);
2758         }
2759 
2760         uc_compiler_parse_consume(compiler, TK_RPAREN);
2761 
2762         /* if we have a condition, jump back to it, else continue to the loop body */
2763         if (cond_off)
2764                 uc_compiler_emit_jmp_dest(compiler, 0, cond_off);
2765 
2766         /* back patch skip address */
2767         uc_compiler_set_jmpaddr(compiler, skip_off, chunk->count);
2768 
2769 
2770         /* Body ----------------------------------------------------------------- */
2771         if (uc_compiler_parse_match(compiler, TK_COLON)) {
2772                 uc_compiler_enter_scope(compiler);
2773 
2774                 if (uc_compiler_compile_delimitted_block(compiler, TK_ENDFOR) == TK_EOF)
2775                         uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
2776                                 "Expecting 'endfor'");
2777                 else
2778                         uc_compiler_parse_advance(compiler);
2779 
2780                 uc_compiler_leave_scope(compiler);
2781         }
2782         else {
2783                 uc_compiler_compile_statement(compiler);
2784         }
2785 
2786         /* jump back to incrementer */
2787         uc_compiler_emit_jmp_dest(compiler, 0, incr_off);
2788 
2789         /* back patch conditional jump */
2790         if (test_off)
2791                 uc_compiler_set_jmpaddr(compiler, test_off, chunk->count);
2792 
2793         /* patch up break/continue */
2794         uc_compiler_backpatch(compiler, chunk->count, incr_off);
2795 
2796         uc_compiler_leave_scope(compiler);
2797 }
2798 
2799 static void
2800 uc_compiler_compile_for(uc_compiler_t *compiler)
2801 {
2802         uc_token_t keyvar = { 0 }, valvar = { 0 };
2803         bool local;
2804 
2805         uc_compiler_parse_consume(compiler, TK_LPAREN);
2806 
2807         /* check the next few tokens and see if we have either a
2808          * `let x in` / `let x, y` expression or an ordinary initializer
2809          * statement */
2810 
2811         local = uc_compiler_parse_match(compiler, TK_LOCAL);
2812 
2813         if (uc_compiler_parse_match(compiler, TK_LABEL)) {
2814                 keyvar = compiler->parser->prev;
2815                 ucv_get(keyvar.uv);
2816 
2817                 if (uc_compiler_parse_match(compiler, TK_COMMA)) {
2818                         uc_compiler_parse_consume(compiler, TK_LABEL);
2819 
2820                         valvar = compiler->parser->prev;
2821                         ucv_get(valvar.uv);
2822                 }
2823 
2824                 /* is a for-in loop */
2825                 if (uc_compiler_parse_match(compiler, TK_IN)) {
2826                         uc_compiler_compile_for_in(compiler, local, &keyvar,
2827                                 valvar.type ? &valvar : NULL);
2828 
2829                         goto out;
2830                 }
2831         }
2832         else if (local) {
2833                 uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
2834                         "Expecting label after 'local'");
2835 
2836                 goto out;
2837         }
2838 
2839         /*
2840          * The previous expression ruled out a for-in loop, so continue parsing
2841          * as counting for loop...
2842          */
2843         uc_compiler_compile_for_count(compiler, local,
2844                 valvar.uv ? &valvar : (keyvar.uv ? &keyvar : NULL));
2845 
2846 out:
2847         ucv_put(keyvar.uv);
2848         ucv_put(valvar.uv);
2849 }
2850 
2851 static void
2852 uc_compiler_compile_switch(uc_compiler_t *compiler)
2853 {
2854         size_t i, test_jmp, skip_jmp, next_jmp = 0, value_slot, default_off = 0;
2855         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
2856         uc_patchlist_t p = { .depth = compiler->scope_depth, .token = TK_SWITCH };
2857         uc_locals_t *locals = &compiler->locals;
2858         uc_jmplist_t cases = { 0 };
2859 
2860         p.parent = compiler->patchlist;
2861         compiler->patchlist = &p;
2862 
2863         uc_compiler_enter_scope(compiler);
2864 
2865         /* parse and compile match value */
2866         uc_compiler_parse_consume(compiler, TK_LPAREN);
2867         uc_compiler_compile_expression(compiler);
2868         uc_compiler_parse_consume(compiler, TK_RPAREN);
2869         uc_compiler_parse_consume(compiler, TK_LBRACE);
2870 
2871         value_slot = uc_compiler_declare_internal(compiler, 0, "(switch value)");
2872 
2873         /* jump to branch tests */
2874         test_jmp = uc_compiler_emit_jmp(compiler, 0);
2875 
2876         /* parse and compile case matches */
2877         while (!uc_compiler_parse_check(compiler, TK_RBRACE) &&
2878                !uc_compiler_parse_check(compiler, TK_EOF)) {
2879                 /* handle `default:` */
2880                 if (uc_compiler_parse_match(compiler, TK_DEFAULT)) {
2881                         if (default_off) {
2882                                 uc_vector_clear(&cases);
2883                                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
2884                                         "more than one switch default case");
2885 
2886                                 break;
2887                         }
2888 
2889                         uc_compiler_parse_consume(compiler, TK_COLON);
2890 
2891                         /* remember address of default branch */
2892                         default_off = chunk->count;
2893 
2894                         /* Store three values in case offset list:
2895                          *  1) amount of local variables declared so far
2896                          *  2) beginning of condition expression
2897                          *  3) end of condition expression
2898                          * For the `default` case, beginning and end offsets of the
2899                          * condition expression are equal.
2900                          */
2901                         uc_vector_extend(&cases, 3);
2902                         cases.entries[cases.count++] = (locals->count - 1) - value_slot;
2903                         cases.entries[cases.count++] = chunk->count;
2904                         cases.entries[cases.count++] = chunk->count;
2905                 }
2906 
2907                 /* handle `case …:` */
2908                 else if (uc_compiler_parse_match(compiler, TK_CASE)) {
2909                         /* jump over `case …:` label expression */
2910                         skip_jmp = uc_compiler_emit_jmp(compiler, 0);
2911 
2912                         /* compile case value expression */
2913                         uc_compiler_compile_expression(compiler);
2914                         uc_compiler_parse_consume(compiler, TK_COLON);
2915 
2916                         /* Store three values in case offset list:
2917                          *  1) amount of local variables declared so far
2918                          *  2) beginning of condition expression
2919                          *  3) end of condition expression
2920                          */
2921                         uc_vector_extend(&cases, 3);
2922                         cases.entries[cases.count++] = (locals->count - 1) - value_slot;
2923                         cases.entries[cases.count++] = skip_jmp + 5;
2924                         cases.entries[cases.count++] = uc_compiler_emit_jmp(compiler, 0);
2925 
2926                         /* patch jump skipping over the case value */
2927                         uc_compiler_set_jmpaddr(compiler, skip_jmp, chunk->count);
2928                 }
2929 
2930                 /* handle interleaved statement */
2931                 else if (cases.count) {
2932                         uc_compiler_compile_declaration(compiler);
2933                 }
2934 
2935                 /* a statement or expression preceding any `default` or `case` is a
2936                  * syntax error */
2937                 else {
2938                         uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
2939                                 "Expecting 'case' or 'default'");
2940 
2941                         break;
2942                 }
2943         }
2944 
2945         uc_compiler_parse_consume(compiler, TK_RBRACE);
2946 
2947         /* evaluate case matches */
2948         if (cases.count) {
2949                 skip_jmp = uc_compiler_emit_jmp(compiler, 0);
2950 
2951                 uc_compiler_set_jmpaddr(compiler, test_jmp, chunk->count);
2952 
2953                 for (i = 0, default_off = cases.count; i < cases.count; i += 3) {
2954                         /* remember and skip default case */
2955                         if (cases.entries[i + 1] == cases.entries[i + 2]) {
2956                                 default_off = i;
2957                                 continue;
2958                         }
2959 
2960                         /* read switch match value */
2961                         uc_compiler_emit_insn(compiler, 0, I_LLOC);
2962                         uc_compiler_emit_u32(compiler, 0, value_slot);
2963 
2964                         /* jump to case value expression code */
2965                         uc_compiler_emit_jmp_dest(compiler, 0, cases.entries[i + 1]);
2966 
2967                         /* patch final case value expression jump back here */
2968                         uc_compiler_set_jmpaddr(compiler, cases.entries[i + 2], chunk->count);
2969 
2970                         /* strict equal test */
2971                         uc_compiler_emit_insn(compiler, 0, I_EQS);
2972 
2973                         /* conditional jump to next match */
2974                         next_jmp = uc_compiler_emit_jmpz(compiler, 0);
2975 
2976                         /* fill local slots */
2977                         while (cases.entries[i + 0] > 0) {
2978                                 uc_compiler_emit_insn(compiler, 0, I_LNULL);
2979                                 cases.entries[i + 0]--;
2980                         }
2981 
2982                         /* jump to target code */
2983                         uc_compiler_emit_jmp_dest(compiler, 0, cases.entries[i + 2] + 5);
2984 
2985                         /* patch next jump */
2986                         uc_compiler_set_jmpaddr(compiler, next_jmp, chunk->count);
2987                 }
2988 
2989                 /* handle default case (if any) */
2990                 if (default_off < cases.count) {
2991                         /* fill local slots */
2992                         while (cases.entries[default_off + 0] > 0) {
2993                                 uc_compiler_emit_insn(compiler, 0, I_LNULL);
2994                                 cases.entries[default_off + 0]--;
2995                         }
2996 
2997                         /* jump to target */
2998                         uc_compiler_emit_jmp_dest(compiler, 0, cases.entries[default_off + 2]);
2999 
3000                         /* do not patch final match failure jump later, we handle it here
3001                          * in the default case */
3002                         next_jmp = 0;
3003                 }
3004 
3005                 uc_compiler_set_jmpaddr(compiler, skip_jmp, chunk->count);
3006         }
3007         else {
3008                 uc_compiler_set_jmpaddr(compiler, test_jmp, test_jmp + 5);
3009         }
3010 
3011         uc_vector_clear(&cases);
3012 
3013         uc_compiler_leave_scope(compiler);
3014 
3015         /* if no default case exists, patch last case match failure jump */
3016         if (next_jmp) {
3017                 /* There's pop instructions for all local variables including the
3018                  * switch test value itself on the stack. Jump onto the last POP
3019                  * instruction (-1) to get rid of the on-stack switch test value
3020                  * but skip the POP instructions for all other scoped local variables
3021                  * which never have been initialized. */
3022                 uc_compiler_set_jmpaddr(compiler, next_jmp, chunk->count - 1);
3023         }
3024 
3025         uc_compiler_backpatch(compiler, chunk->count, 0);
3026 }
3027 
3028 static void
3029 uc_compiler_compile_try(uc_compiler_t *compiler)
3030 {
3031         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
3032         size_t try_from = 0, try_to = 0, jmp_off = 0, ehvar_slot = 0;
3033         uc_ehranges_t *ranges = &chunk->ehranges;
3034 
3035         try_from = chunk->count;
3036         ehvar_slot = compiler->locals.count;
3037 
3038         /* Try block ------------------------------------------------------------ */
3039         uc_compiler_enter_scope(compiler);
3040 
3041         uc_compiler_parse_consume(compiler, TK_LBRACE);
3042 
3043         while (!uc_compiler_parse_check(compiler, TK_RBRACE) &&
3044                !uc_compiler_parse_check(compiler, TK_EOF))
3045                 uc_compiler_compile_declaration(compiler);
3046 
3047         uc_compiler_parse_consume(compiler, TK_RBRACE);
3048 
3049         uc_compiler_leave_scope(compiler);
3050 
3051         /* jump beyond catch branch */
3052         try_to = chunk->count;
3053         jmp_off = uc_compiler_emit_jmp(compiler, 0);
3054 
3055 
3056         /* Catch block ---------------------------------------------------------- */
3057         if (try_to > try_from) {
3058                 uc_vector_push(ranges, {
3059                         .from   = try_from,
3060                         .to     = try_to,
3061                         .target = chunk->count,
3062                         .slot   = ehvar_slot
3063                 });
3064         }
3065 
3066         uc_compiler_enter_scope(compiler);
3067 
3068         uc_compiler_parse_consume(compiler, TK_CATCH);
3069 
3070         /* have exception variable */
3071         if (uc_compiler_parse_match(compiler, TK_LPAREN)) {
3072                 uc_compiler_parse_consume(compiler, TK_LABEL);
3073 
3074                 uc_compiler_declare_local(compiler, compiler->parser->prev.uv, false);
3075                 uc_compiler_initialize_local(compiler);
3076 
3077                 uc_compiler_parse_consume(compiler, TK_RPAREN);
3078         }
3079         /* ... else pop exception object from stack */
3080         else {
3081                 uc_compiler_emit_insn(compiler, 0, I_POP);
3082         }
3083 
3084         uc_compiler_parse_consume(compiler, TK_LBRACE);
3085 
3086         while (!uc_compiler_parse_check(compiler, TK_RBRACE) &&
3087                !uc_compiler_parse_check(compiler, TK_EOF))
3088                 uc_compiler_compile_declaration(compiler);
3089 
3090         uc_compiler_parse_consume(compiler, TK_RBRACE);
3091 
3092         uc_compiler_leave_scope(compiler);
3093 
3094         uc_compiler_set_jmpaddr(compiler, jmp_off, chunk->count);
3095 }
3096 
3097 static void
3098 uc_compiler_compile_control(uc_compiler_t *compiler)
3099 {
3100         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
3101         uc_tokentype_t type = compiler->parser->prev.type;
3102         uc_patchlist_t *p = compiler->patchlist;
3103         uc_locals_t *locals = &compiler->locals;
3104         size_t i, pos = compiler->parser->prev.pos;
3105 
3106         /* select applicable patchlist: for continue statements select the
3107          * first non-switch scope */
3108         while (p) {
3109                 if (type != TK_CONTINUE || p->token != TK_SWITCH)
3110                         break;
3111 
3112                 p = p->parent;
3113         }
3114 
3115         if (!p || p->token == TK_EXPORT) {
3116                 uc_compiler_syntax_error(compiler, pos,
3117                         (type == TK_BREAK)
3118                                 ? "break must be inside loop or switch"
3119                                 : "continue must be inside loop");
3120 
3121                 return;
3122         }
3123 
3124         /* pop locals in all scopes covered by the target patchlist */
3125         for (i = locals->count; i > 0 && (size_t)locals->entries[i - 1].depth > p->depth; i--)
3126                 uc_compiler_emit_insn(compiler, 0,
3127                         locals->entries[i - 1].captured ? I_CUPV : I_POP);
3128 
3129         uc_vector_push(p,
3130                 uc_compiler_emit_jmp_dest(compiler, pos, chunk->count + type));
3131 
3132         uc_compiler_parse_consume(compiler, TK_SCOL);
3133 }
3134 
3135 static void
3136 uc_compiler_compile_return(uc_compiler_t *compiler)
3137 {
3138         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
3139 
3140         if (compiler->function->module) {
3141                 uc_compiler_syntax_error(compiler, 0, "return must be inside function body");
3142 
3143                 return;
3144         }
3145 
3146         /* if we compiled an empty expression statement (`;`), load implicit null */
3147         if (uc_compiler_compile_expstmt(compiler) == TK_NULL)
3148                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_LNULL);
3149 
3150         /* otherwise overwrite the final I_POP instruction with I_RETURN */
3151         else
3152                 uc_chunk_pop(chunk);
3153 
3154         uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_RETURN);
3155 }
3156 
3157 static void
3158 uc_compiler_compile_tplexp(uc_compiler_t *compiler)
3159 {
3160         uc_chunk_t *chunk = uc_compiler_current_chunk(compiler);
3161         size_t off = chunk->count;
3162 
3163         uc_compiler_compile_expression(compiler);
3164 
3165         /* XXX: the lexer currently emits a superfluous trailing semicolon... */
3166         uc_compiler_parse_match(compiler, TK_SCOL);
3167 
3168         uc_compiler_parse_consume(compiler, TK_REXP);
3169 
3170         if (chunk->count > off)
3171                 uc_compiler_emit_insn(compiler, 0, I_PRINT);
3172 }
3173 
3174 static void
3175 uc_compiler_compile_text(uc_compiler_t *compiler)
3176 {
3177         uc_compiler_emit_constant(compiler, compiler->parser->prev.pos, compiler->parser->prev.uv);
3178         uc_compiler_emit_insn(compiler, 0, I_PRINT);
3179 }
3180 
3181 static uc_tokentype_t
3182 uc_compiler_compile_block(uc_compiler_t *compiler)
3183 {
3184         uc_tokentype_t last_statement_type = TK_NULL;
3185 
3186         uc_compiler_enter_scope(compiler);
3187 
3188         while (!uc_compiler_parse_check(compiler, TK_RBRACE) &&
3189                !uc_compiler_parse_check(compiler, TK_EOF))
3190                 last_statement_type = uc_compiler_compile_declaration(compiler);
3191 
3192         uc_compiler_parse_consume(compiler, TK_RBRACE);
3193 
3194         uc_compiler_leave_scope(compiler);
3195 
3196         return last_statement_type;
3197 }
3198 
3199 static uc_tokentype_t
3200 uc_compiler_compile_expstmt(uc_compiler_t *compiler)
3201 {
3202         /* empty statement */
3203         if (uc_compiler_parse_match(compiler, TK_SCOL))
3204                 return TK_NULL;
3205 
3206         uc_compiler_compile_expression(compiler);
3207 
3208         /* allow omitting final semicolon */
3209         switch (compiler->parser->curr.type) {
3210         case TK_RBRACE:
3211         case TK_ELIF:
3212         case TK_ENDIF:
3213         case TK_ENDFOR:
3214         case TK_ENDWHILE:
3215         case TK_ENDFUNC:
3216         case TK_EOF:
3217                 break;
3218 
3219         case TK_ELSE:
3220                 if (!uc_compiler_exprstack_is(compiler, F_ALTBLOCKMODE))
3221                         uc_compiler_parse_consume(compiler, TK_SCOL);
3222 
3223                 break;
3224 
3225         default:
3226                 uc_compiler_parse_consume(compiler, TK_SCOL);
3227 
3228                 break;
3229         }
3230 
3231         uc_compiler_emit_insn(compiler, 0, I_POP);
3232 
3233         return TK_SCOL;
3234 }
3235 
3236 static uc_tokentype_t
3237 uc_compiler_compile_statement(uc_compiler_t *compiler)
3238 {
3239         uc_tokentype_t last_statement_type = compiler->parser->curr.type;
3240         uc_exprstack_t expr = {
3241                 .token = compiler->parser->curr.type,
3242                 .parent = compiler->exprstack
3243         };
3244 
3245         compiler->exprstack = &expr;
3246 
3247         if (uc_compiler_parse_match(compiler, TK_IF))
3248                 uc_compiler_compile_if(compiler);
3249         else if (uc_compiler_parse_match(compiler, TK_WHILE))
3250                 uc_compiler_compile_while(compiler);
3251         else if (uc_compiler_parse_match(compiler, TK_FOR))
3252                 uc_compiler_compile_for(compiler);
3253         else if (uc_compiler_parse_match(compiler, TK_SWITCH))
3254                 uc_compiler_compile_switch(compiler);
3255         else if (uc_compiler_parse_match(compiler, TK_TRY))
3256                 uc_compiler_compile_try(compiler);
3257         else if (uc_compiler_parse_match(compiler, TK_FUNC))
3258                 uc_compiler_compile_funcdecl(compiler);
3259         else if (uc_compiler_parse_match(compiler, TK_BREAK))
3260                 uc_compiler_compile_control(compiler);
3261         else if (uc_compiler_parse_match(compiler, TK_CONTINUE))
3262                 uc_compiler_compile_control(compiler);
3263         else if (uc_compiler_parse_match(compiler, TK_RETURN))
3264                 uc_compiler_compile_return(compiler);
3265         else if (uc_compiler_parse_match(compiler, TK_TEXT))
3266                 uc_compiler_compile_text(compiler);
3267         else if (uc_compiler_parse_match(compiler, TK_LEXP))
3268                 uc_compiler_compile_tplexp(compiler);
3269         else if (uc_compiler_parse_match(compiler, TK_LBRACE))
3270                 last_statement_type = uc_compiler_compile_block(compiler);
3271         else
3272                 last_statement_type = uc_compiler_compile_expstmt(compiler);
3273 
3274         compiler->exprstack = expr.parent;
3275 
3276         return last_statement_type;
3277 }
3278 
3279 static void
3280 uc_compiler_export_add(uc_compiler_t *compiler, uc_value_t *name, ssize_t slot)
3281 {
3282         uc_source_t *source = uc_compiler_current_source(compiler);
3283 
3284         uc_compiler_inc_exportnum(compiler);
3285 
3286         if (!uc_source_export_add(source, name)) {
3287                 if (name)
3288                         uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3289                                 "Duplicate export '%s' for module '%s'", ucv_string_get(name), source->filename);
3290                 else
3291                         uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3292                                 "Duplicate default export for module '%s'", source->filename);
3293         }
3294         else {
3295                 uc_vector_push(compiler->patchlist, slot);
3296         }
3297 }
3298 
3299 static void
3300 uc_compiler_compile_exportlist(uc_compiler_t *compiler)
3301 {
3302         uc_value_t *label, *name;
3303         bool constant;
3304         ssize_t slot;
3305 
3306         /* parse export symbols */
3307         do {
3308                 uc_compiler_parse_consume(compiler, TK_LABEL);
3309 
3310                 label = ucv_get(compiler->parser->prev.uv);
3311                 name = NULL;
3312 
3313                 slot = uc_compiler_resolve_local(compiler, label, &constant);
3314 
3315                 if (slot == -1) {
3316                         uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3317                                 "Attempt to export undeclared or non-local variable '%s'",
3318                                 ucv_string_get(label));
3319                 }
3320 
3321                 if (uc_compiler_keyword_match(compiler, "as")) {
3322                         if (uc_compiler_parse_match(compiler, TK_LABEL) || uc_compiler_parse_match(compiler, TK_STRING)) {
3323                                 name = ucv_get(compiler->parser->prev.uv);
3324                         }
3325                         else if (!uc_compiler_parse_match(compiler, TK_DEFAULT)) {
3326                                 uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
3327                                         "Unexpected token\nExpecting Label, String or 'default'");
3328                         }
3329                 }
3330                 else {
3331                         name = ucv_get(label);
3332                 }
3333 
3334                 uc_compiler_export_add(compiler, name, slot);
3335 
3336                 ucv_put(label);
3337                 ucv_put(name);
3338 
3339                 if (uc_compiler_parse_match(compiler, TK_RBRACE))
3340                         break;
3341         }
3342         while (uc_compiler_parse_match(compiler, TK_COMMA));
3343 
3344         uc_compiler_parse_consume(compiler, TK_SCOL);
3345 }
3346 
3347 static void
3348 uc_compiler_compile_export(uc_compiler_t *compiler)
3349 {
3350         uc_locals_t *locals = &compiler->locals;
3351         size_t off = locals->count;
3352         uc_value_t *name;
3353         ssize_t slot;
3354 
3355         if (!compiler->function->module || compiler->scope_depth) {
3356                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3357                         "Exports may only appear at top level of a module");
3358 
3359                 return;
3360         }
3361 
3362         if (uc_compiler_parse_match(compiler, TK_LBRACE)) {
3363                 uc_compiler_compile_exportlist(compiler);
3364 
3365                 return;
3366         }
3367 
3368         if (uc_compiler_parse_match(compiler, TK_LOCAL))
3369                 uc_compiler_compile_declexpr(compiler, false);
3370         else if (uc_compiler_parse_match(compiler, TK_CONST))
3371                 uc_compiler_compile_declexpr(compiler, true);
3372         else if (uc_compiler_parse_match(compiler, TK_FUNC)) {
3373                 uc_compiler_compile_funcdecl(compiler);
3374 
3375                 for (; off < locals->count; off++)
3376                         uc_compiler_export_add(compiler, locals->entries[off].name, off);
3377 
3378                 return;
3379         }
3380         else if (uc_compiler_parse_match(compiler, TK_DEFAULT))
3381                 uc_compiler_compile_expression(compiler);
3382         else
3383                 uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
3384                         "Unexpected token\nExpecting 'let', 'const', 'function', 'default' or '{'");
3385 
3386         if (off == locals->count) {
3387                 name = ucv_string_new("(module default export)");
3388                 slot = uc_compiler_declare_local(compiler, name, true);
3389                 ucv_put(name);
3390 
3391                 if (slot != -1)
3392                         uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3393                                 "Duplicate default export statement");
3394                 else
3395                         uc_compiler_export_add(compiler, NULL, compiler->locals.count - 1);
3396         }
3397         else {
3398                 for (; off < locals->count; off++)
3399                         uc_compiler_export_add(compiler, locals->entries[off].name, off);
3400         }
3401 
3402         uc_compiler_parse_consume(compiler, TK_SCOL);
3403 }
3404 
3405 static uc_program_t *
3406 uc_compile_from_source(uc_parse_config_t *config, uc_source_t *source, uc_program_t *prog, char **errp);
3407 
3408 static bool
3409 uc_compiler_compile_dynload(uc_compiler_t *compiler, const char *name, uc_value_t *imports)
3410 {
3411         uc_value_t *modname = ucv_string_new(name);
3412         size_t i, n_imports;
3413         uc_value_t *import;
3414 
3415         for (i = 0, n_imports = 0; i < ucv_array_length(imports); i++) {
3416                 import = ucv_array_get(imports, i);
3417 
3418                 if (ucv_boolean_get(import)) {
3419                         uc_compiler_emit_constant(compiler, 0, modname);
3420                         uc_compiler_emit_insn(compiler, 0, I_DYNLOAD);
3421                         uc_compiler_emit_u32(compiler, 0, 0);
3422                 }
3423                 else {
3424                         n_imports++;
3425                 }
3426         }
3427 
3428         if (n_imports > 0) {
3429                 uc_compiler_emit_constant(compiler, 0, modname);
3430                 uc_compiler_emit_insn(compiler, 0, I_DYNLOAD);
3431                 uc_compiler_emit_u32(compiler, 0, n_imports | ((compiler->upvals.count - n_imports) << 16));
3432 
3433                 for (i = 0; i < ucv_array_length(imports); i++) {
3434                         import = ucv_get(ucv_array_get(imports, i));
3435 
3436                         if (!import)
3437                                 import = ucv_string_new("default");
3438 
3439                         if (!ucv_boolean_get(import))
3440                                 uc_compiler_emit_constant_index(compiler, 0, import);
3441 
3442                         ucv_put(import);
3443                 }
3444         }
3445 
3446         ucv_put(modname);
3447 
3448         return true;
3449 }
3450 
3451 static bool
3452 uc_compiler_compile_module_source(uc_compiler_t *compiler, const char *modname, uc_source_t *source, uc_value_t *imports, char **errp)
3453 {
3454         uc_parse_config_t config = {
3455                 .raw_mode = true,
3456                 .strict_declarations = true,
3457                 .module_search_path = compiler->parser->lex.config->module_search_path
3458         };
3459 
3460         size_t i, load_idx = 0, n_imports = 0;
3461         bool loaded = false;
3462         uc_value_t *import;
3463         ssize_t slot;
3464 
3465         uc_program_function_foreach(compiler->program, fn) {
3466                 if (uc_program_function_source(fn) == source) {
3467                         if (source->exports.offset == (size_t)-1)
3468                                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3469                                         "Circular dependency");
3470 
3471                         loaded = true;
3472                         break;
3473                 }
3474         }
3475 
3476         if (!loaded) {
3477                 /* We do not yet support linking precompiled modules at compile time,
3478                    turn static import operation into dynamic load one. */
3479                 if (uc_source_type_test(source) == UC_SOURCE_TYPE_PRECOMPILED)
3480                         return uc_compiler_compile_dynload(compiler, modname, imports);
3481 
3482                 load_idx = uc_program_function_id(compiler->program,
3483                         uc_program_function_last(compiler->program)) + 1;
3484 
3485                 source->exports.offset = (size_t)-1;
3486 
3487                 if (!uc_compile_from_source(&config, source, compiler->program, errp))
3488                         return false;
3489 
3490                 source->exports.offset = uc_compiler_get_exportnum(compiler) - source->exports.count;
3491                 uc_compiler_current_source(compiler)->exports.offset += source->exports.count;
3492 
3493                 /* emit load, call & pop instructions */
3494                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_CLFN);
3495                 uc_compiler_emit_u32(compiler, 0, load_idx);
3496 
3497                 uc_compiler_emit_insn(compiler, 0, I_CALL);
3498                 uc_compiler_emit_u32(compiler, 0, 0);
3499 
3500                 uc_compiler_emit_insn(compiler, 0, I_POP);
3501         }
3502 
3503         /* count imports, handle wildcard imports */
3504         for (i = 0; i < ucv_array_length(imports); i++) {
3505                 if (ucv_boolean_get(ucv_array_get(imports, i))) {
3506                         if (source->exports.offset > 0xffff || source->exports.count > 0xffff) {
3507                                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3508                                         "Too many module exports");
3509                         }
3510 
3511                         /* emit import instruction... */
3512                         uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_IMPORT);
3513                         uc_compiler_emit_u32(compiler, 0, source->exports.count | (0xffff << 16));
3514 
3515                         /* ... followed by first module export offset ... */
3516                         uc_compiler_emit_u16(compiler, 0, source->exports.offset);
3517 
3518                         /* ... and constant indexes for all exported names */
3519                         for (load_idx = 0; load_idx < source->exports.count; load_idx++) {
3520                                 if (source->exports.entries[load_idx])
3521                                         import = ucv_get(source->exports.entries[load_idx]);
3522                                 else
3523                                         import = ucv_string_new("default");
3524 
3525                                 uc_compiler_emit_constant_index(compiler, 0, import);
3526                                 ucv_put(import);
3527                         }
3528 
3529                 }
3530                 else {
3531                         n_imports++;
3532                 }
3533         }
3534 
3535         /* 0xffff is reserved for wildcard import */
3536         if (n_imports > 0xfffe)
3537                 uc_compiler_syntax_error(compiler, 0, "Too many imports");
3538 
3539         /* emit non-wildcard import instructions */
3540         for (i = 0; i < ucv_array_length(imports); i++) {
3541                 import = ucv_array_get(imports, i);
3542 
3543                 if (!ucv_boolean_get(import)) {
3544                         slot = uc_source_export_lookup(source, import);
3545 
3546                         if (slot == -1) {
3547                                 if (import)
3548                                         uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3549                                                 "Module %s does not export '%s'", source->filename, ucv_string_get(import));
3550                                 else
3551                                         uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3552                                                 "Module %s has no default export", source->filename);
3553                         }
3554                         else if (slot > 0xffff) {
3555                                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3556                                         "Too many module exports");
3557                         }
3558                         else {
3559                                 uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_IMPORT);
3560                                 uc_compiler_emit_u32(compiler, 0,
3561                                         (source->exports.offset + slot) | ((compiler->upvals.count - n_imports + i) << 16));
3562                         }
3563                 }
3564         }
3565 
3566         return true;
3567 }
3568 
3569 static char *
3570 uc_compiler_canonicalize_path(const char *path, const char *runpath)
3571 {
3572         char *p, *resolved;
3573         const char *slash;
3574 
3575         if (*path == '/')
3576                 xasprintf(&p, "%s", path);
3577         else if (runpath && (slash = strrchr(runpath, '/')) != NULL)
3578                 xasprintf(&p, "%.*s/%s", (int)(slash - runpath), runpath, path);
3579         else
3580                 xasprintf(&p, "./%s", path);
3581 
3582         resolved = realpath(p, NULL);
3583 
3584         free(p);
3585 
3586         return resolved;
3587 }
3588 
3589 static char *
3590 uc_compiler_expand_module_path(const char *name, const char *runpath, const char *template)
3591 {
3592         int namelen, prefixlen;
3593         const char *asterix;
3594         char *path, *p;
3595 
3596         asterix = strchr(template, '*');
3597 
3598         if (!asterix)
3599                 return NULL;
3600 
3601         prefixlen = asterix - template;
3602         namelen = strlen(name);
3603 
3604         xasprintf(&path, "%.*s%.*s%s", prefixlen, template, namelen, name, asterix + 1);
3605 
3606         for (p = path + prefixlen; namelen > 0; namelen--, p++)
3607                 if (*p == '.')
3608                         *p = '/';
3609 
3610         p = uc_compiler_canonicalize_path(path, runpath);
3611 
3612         free(path);
3613 
3614         return p;
3615 }
3616 
3617 static char *
3618 uc_compiler_resolve_module_path(uc_compiler_t *compiler, const char *name)
3619 {
3620         uc_search_path_t *search = &compiler->parser->lex.config->module_search_path;
3621         uc_source_t *source = uc_compiler_current_source(compiler);
3622         char *path = NULL;
3623         size_t i;
3624 
3625         if (strchr(name, '/'))
3626                 return uc_compiler_canonicalize_path(name, source->runpath);
3627 
3628         for (i = 0; i < search->count && !path; i++)
3629                 path = uc_compiler_expand_module_path(name, source->runpath, search->entries[i]);
3630 
3631         return path;
3632 }
3633 
3634 static uc_source_t *
3635 uc_compiler_acquire_source(uc_compiler_t *compiler, const char *path)
3636 {
3637         size_t i;
3638 
3639         for (i = 0; i < compiler->program->sources.count; i++)
3640                 if (!strcmp(compiler->program->sources.entries[i]->filename, path))
3641                         return uc_source_get(compiler->program->sources.entries[i]);
3642 
3643         return uc_source_new_file(path);
3644 }
3645 
3646 static bool
3647 uc_compiler_is_dynlink_module(uc_compiler_t *compiler, const char *name, const char *path)
3648 {
3649         uc_search_path_t *dynlink_list = &compiler->parser->config->force_dynlink_list;
3650         const char *dot;
3651         size_t i;
3652 
3653         for (i = 0; i < dynlink_list->count; i++)
3654                 if (!strcmp(dynlink_list->entries[i], name))
3655                         return true;
3656 
3657         if (!path)
3658                 return false;
3659 
3660         dot = strrchr(path, '.');
3661 
3662         return (dot && !strcmp(dot, ".so"));
3663 }
3664 
3665 static bool
3666 uc_compiler_compile_module(uc_compiler_t *compiler, const char *name, uc_value_t *imports)
3667 {
3668         uc_source_t *source;
3669         char *path, *err;
3670         bool res;
3671 
3672         if (!name)
3673                 return false;
3674 
3675         path = uc_compiler_resolve_module_path(compiler, name);
3676 
3677         if (uc_compiler_is_dynlink_module(compiler, name, path)) {
3678                 res = uc_compiler_compile_dynload(compiler, name, imports);
3679         }
3680         else if (path) {
3681                 source = uc_compiler_acquire_source(compiler, path);
3682 
3683                 if (source) {
3684                         err = NULL;
3685                         res = uc_compiler_compile_module_source(compiler, name, source, imports, &err);
3686 
3687                         if (!res) {
3688                                 uc_error_message_indent(&err);
3689                                 uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
3690                                         "Unable to compile module '%s':\n\n%s", source->filename, err);
3691                         }
3692 
3693                         free(err);
3694                 }
3695                 else {
3696                         uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
3697                                 "Unable to open module '%s': %s",
3698                                 path, strerror(errno));
3699 
3700                         res = false;
3701                 }
3702 
3703                 uc_source_put(source);
3704         }
3705         else {
3706                 uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
3707                         "Unable to resolve path for module '%s'", name);
3708 
3709                 return false;
3710         }
3711 
3712         free(path);
3713 
3714         return res;
3715 }
3716 
3717 static void
3718 uc_compiler_import_add(uc_compiler_t *compiler, uc_value_t *name)
3719 {
3720         bool constant;
3721         ssize_t slot;
3722 
3723         slot = uc_compiler_resolve_local(compiler, name, &constant);
3724 
3725         if (slot != -1) {
3726                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3727                         "Import name '%s' is already declared as local variable",
3728                         ucv_string_get(name));
3729 
3730                 return;
3731         }
3732 
3733         slot = uc_compiler_resolve_upval(compiler, name, &constant);
3734 
3735         if (slot != -1) {
3736                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3737                         "Import name '%s' is already used",
3738                         ucv_string_get(name));
3739 
3740                 return;
3741         }
3742 
3743         uc_compiler_add_upval(compiler, (2 << 14) + compiler->upvals.count, false, name, true);
3744 }
3745 
3746 static void
3747 uc_compiler_compile_importlist(uc_compiler_t *compiler, uc_value_t *namelist)
3748 {
3749         uc_value_t *label, *name;
3750 
3751         /* parse export symbols */
3752         do {
3753                 name = NULL;
3754                 label = NULL;
3755 
3756                 if (uc_compiler_parse_match(compiler, TK_DEFAULT)) {
3757                         uc_compiler_keyword_consume(compiler, "as");
3758                         uc_compiler_parse_consume(compiler, TK_LABEL);
3759 
3760                         label = ucv_get(compiler->parser->prev.uv);
3761                 }
3762                 else if (uc_compiler_parse_match(compiler, TK_STRING)) {
3763                         name = ucv_get(compiler->parser->prev.uv);
3764 
3765                         uc_compiler_keyword_consume(compiler, "as");
3766                         uc_compiler_parse_consume(compiler, TK_LABEL);
3767 
3768                         label = ucv_get(compiler->parser->prev.uv);
3769                 }
3770                 else if (uc_compiler_parse_match(compiler, TK_LABEL)) {
3771                         name = ucv_get(compiler->parser->prev.uv);
3772 
3773                         if (uc_compiler_keyword_match(compiler, "as")) {
3774                                 uc_compiler_parse_consume(compiler, TK_LABEL);
3775 
3776                                 label = ucv_get(compiler->parser->prev.uv);
3777                         }
3778                         else {
3779                                 label = ucv_get(name);
3780                         }
3781                 }
3782                 else {
3783                         uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
3784                                 "Unexpected token\nExpecting Label, String or 'default'");
3785                 }
3786 
3787                 uc_compiler_import_add(compiler, label);
3788                 ucv_array_push(namelist, name);
3789                 ucv_put(label);
3790 
3791                 if (uc_compiler_parse_match(compiler, TK_RBRACE))
3792                         return;
3793         }
3794         while (uc_compiler_parse_match(compiler, TK_COMMA));
3795 
3796         uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
3797                 "Unexpected token\nExpecting 'as', ',' or '}'");
3798 }
3799 
3800 static void
3801 uc_compiler_compile_importcall(uc_compiler_t *compiler)
3802 {
3803         uc_compiler_parse_consume(compiler, TK_LPAREN);
3804         uc_compiler_parse_precedence(compiler, P_ASSIGN);
3805         uc_compiler_parse_consume(compiler, TK_RPAREN);
3806 
3807         uc_compiler_emit_insn(compiler, compiler->parser->prev.pos, I_DYNLOAD);
3808         uc_compiler_emit_u32(compiler, 0, 0);
3809 }
3810 
3811 static uc_tokentype_t
3812 uc_compiler_compile_import(uc_compiler_t *compiler)
3813 {
3814         uc_value_t *namelist;
3815 
3816         /* import(...) */
3817         if (uc_compiler_parse_check(compiler, TK_LPAREN)) {
3818                 uc_compiler_parse_precedence_for_token(compiler, P_UNARY,
3819                                                        &compiler->parser->prev);
3820 
3821                 uc_compiler_emit_insn(compiler, 0, I_POP);
3822 
3823                 return TK_SCOL;
3824         }
3825 
3826         if (compiler->scope_depth) {
3827                 uc_compiler_syntax_error(compiler, compiler->parser->prev.pos,
3828                         "Imports may only appear at top level");
3829 
3830                 return TK_IMPORT;
3831         }
3832 
3833         namelist = ucv_array_new(NULL);
3834 
3835         /* import { ... } from */
3836         if (uc_compiler_parse_match(compiler, TK_LBRACE)) {
3837                 uc_compiler_compile_importlist(compiler, namelist);
3838                 uc_compiler_keyword_consume(compiler, "from");
3839         }
3840 
3841         /* import * as name from */
3842         else if (uc_compiler_parse_match(compiler, TK_MUL)) {
3843                 uc_compiler_keyword_consume(compiler, "as");
3844                 uc_compiler_parse_consume(compiler, TK_LABEL);
3845 
3846                 uc_compiler_declare_local(compiler, compiler->parser->prev.uv, true);
3847                 uc_compiler_initialize_local(compiler);
3848                 ucv_array_push(namelist, ucv_boolean_new(true));
3849 
3850                 uc_compiler_keyword_consume(compiler, "from");
3851         }
3852 
3853         /* import defaultExport [, ... ] from */
3854         else if (uc_compiler_parse_match(compiler, TK_LABEL)) {
3855                 uc_compiler_import_add(compiler, compiler->parser->prev.uv);
3856                 ucv_array_push(namelist, NULL);
3857 
3858                 /* import defaultExport, ... from */
3859                 if (uc_compiler_parse_match(compiler, TK_COMMA)) {
3860                         /* import defaultExport, { ... } from */
3861                         if (uc_compiler_parse_match(compiler, TK_LBRACE)) {
3862                                 uc_compiler_compile_importlist(compiler, namelist);
3863                         }
3864 
3865                         /* import defaultExport, * as name from */
3866                         else if (uc_compiler_parse_match(compiler, TK_MUL)) {
3867                                 uc_compiler_keyword_consume(compiler, "as");
3868                                 uc_compiler_parse_consume(compiler, TK_LABEL);
3869 
3870                                 uc_compiler_declare_local(compiler, compiler->parser->prev.uv, true);
3871                                 uc_compiler_initialize_local(compiler);
3872                                 ucv_array_push(namelist, ucv_boolean_new(true));
3873                         }
3874 
3875                         /* error */
3876                         else {
3877                                 uc_compiler_syntax_error(compiler, compiler->parser->curr.pos,
3878                                         "Unexpected token\nExpecting '{' or '*'");
3879                         }
3880                 }
3881 
3882                 uc_compiler_keyword_consume(compiler, "from");
3883         }
3884 
3885         uc_compiler_parse_consume(compiler, TK_STRING);
3886 
3887         uc_compiler_compile_module(compiler, ucv_string_get(compiler->parser->prev.uv), namelist);
3888 
3889         uc_compiler_parse_consume(compiler, TK_SCOL);
3890 
3891         ucv_put(namelist);
3892 
3893         return TK_IMPORT;
3894 }
3895 
3896 static uc_tokentype_t
3897 uc_compiler_compile_declaration(uc_compiler_t *compiler)
3898 {
3899         uc_tokentype_t last_statement_type = compiler->parser->curr.type;
3900 
3901         if (uc_compiler_parse_match(compiler, TK_LOCAL))
3902                 uc_compiler_compile_local(compiler);
3903         else if (uc_compiler_parse_match(compiler, TK_CONST))
3904                 uc_compiler_compile_const(compiler);
3905         else if (uc_compiler_parse_match(compiler, TK_EXPORT))
3906                 uc_compiler_compile_export(compiler);
3907         else if (uc_compiler_parse_match(compiler, TK_IMPORT))
3908                 last_statement_type = uc_compiler_compile_import(compiler);
3909         else
3910                 last_statement_type = uc_compiler_compile_statement(compiler);
3911 
3912         if (compiler->parser->synchronizing)
3913                 uc_compiler_parse_synchronize(compiler);
3914 
3915         return last_statement_type;
3916 }
3917 
3918 #endif /* NO_COMPILE */
3919 
3920 
3921 static uc_program_t *
3922 uc_compile_from_source(uc_parse_config_t *config, uc_source_t *source, uc_program_t *prog, char **errp)
3923 {
3924 #ifdef NO_COMPILE
3925         if (errp)
3926                 xasprintf(errp, "Source code compilation not supported\n");
3927 
3928         return NULL;
3929 #else
3930         bool is_module = (prog != NULL) || (config && config->compile_module);
3931         uc_patchlist_t exports = { .token = TK_EXPORT };
3932         uc_exprstack_t expr = { .token = TK_EOF };
3933         uc_parser_t parser = { .config = config };
3934         uc_compiler_t compiler = { .parser = &parser, .exprstack = &expr };
3935         uc_tokentype_t last_statement_type = TK_NULL;
3936         uc_program_t *progptr;
3937         uc_function_t *fn;
3938         const char *name;
3939 
3940         if (!prog) {
3941                 progptr = uc_program_new();
3942                 name = is_module ? "module" : "main";
3943         }
3944         else {
3945                 progptr = prog;
3946                 name = "module";
3947         }
3948 
3949         uc_lexer_init(&parser.lex, config, source);
3950         uc_compiler_init(&compiler, name, source, 0, progptr,
3951                 config && config->strict_declarations);
3952 
3953         if (is_module) {
3954                 compiler.patchlist = &exports;
3955                 compiler.function->module = true;
3956         }
3957 
3958         uc_compiler_parse_advance(&compiler);
3959 
3960         while (!uc_compiler_parse_match(&compiler, TK_EOF))
3961                 last_statement_type = uc_compiler_compile_declaration(&compiler);
3962 
3963         if (!compiler.function->module && last_statement_type == TK_SCOL) {
3964                 uc_chunk_pop(uc_compiler_current_chunk(&compiler));
3965                 uc_compiler_emit_insn(&compiler, 0, I_RETURN);
3966                 last_statement_type = TK_RETURN;
3967         }
3968 
3969         fn = uc_compiler_finish(&compiler, last_statement_type);
3970 
3971         if (errp) {
3972                 *errp = parser.error ? parser.error->buf : NULL;
3973                 free(parser.error);
3974         }
3975         else {
3976                 printbuf_free(parser.error);
3977         }
3978 
3979         uc_lexer_free(&parser.lex);
3980         uc_vector_clear(&exports);
3981 
3982         if (!fn) {
3983                 if (progptr != prog)
3984                         ucv_put(&progptr->header);
3985 
3986                 return NULL;
3987         }
3988 
3989         return progptr;
3990 #endif
3991 }
3992 
3993 static uc_program_t *
3994 uc_compile_from_bytecode(uc_parse_config_t *config, uc_source_t *source, char **errp)
3995 {
3996         uc_program_t *prog;
3997 
3998         prog = uc_program_load(source, errp);
3999 
4000         if (prog && !uc_program_entry(prog)) {
4001                 if (errp)
4002                         xasprintf(errp, "Program file contains no entry function\n");
4003 
4004                 ucv_put(&prog->header);
4005         }
4006 
4007         return prog;
4008 }
4009 
4010 uc_program_t *
4011 uc_compile(uc_parse_config_t *config, uc_source_t *source, char **errp)
4012 {
4013         uc_program_t *prog = NULL;
4014 
4015         if (!config)
4016                 config = &uc_default_parse_config;
4017 
4018         switch (uc_source_type_test(source)) {
4019         case UC_SOURCE_TYPE_PLAIN:
4020                 prog = uc_compile_from_source(config, source, NULL, errp);
4021                 break;
4022 
4023         case UC_SOURCE_TYPE_PRECOMPILED:
4024                 prog = uc_compile_from_bytecode(config, source, errp);
4025                 break;
4026 
4027         default:
4028                 if (errp)
4029                         xasprintf(errp, "Unrecognized source type\n");
4030 
4031                 break;
4032         }
4033 
4034         return prog;
4035 }
4036 

This page was automatically generated by LXR 0.3.1.  •  OpenWrt