1 /* Go language support routines for GDB, the GNU debugger.
3 Copyright (C) 2012-2019 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 - printing of native types
25 - gccgo mangling needs redoing
26 It's too hard, for example, to know whether one is looking at a mangled
27 Go symbol or not, and their are ambiguities, e.g., the demangler may
28 get passed *any* symbol, including symbols from other languages
29 and including symbols that are already demangled.
30 One thought is to at least add an _G prefix.
31 - 6g mangling isn't supported yet
35 #include "gdb_obstack.h"
42 #include "parser-defs.h"
46 /* The main function in the main package. */
47 static const char GO_MAIN_MAIN[] = "main.main";
49 /* Function returning the special symbol name used by Go for the main
50 procedure in the main program if it is found in minimal symbol list.
51 This function tries to find minimal symbols so that it finds them even
52 if the program was compiled without debugging information. */
57 struct bound_minimal_symbol msym;
59 msym = lookup_minimal_symbol (GO_MAIN_MAIN, NULL, NULL);
60 if (msym.minsym != NULL)
63 /* No known entry procedure found, the main program is probably not Go. */
67 /* Return non-zero if TYPE is a gccgo string.
68 We assume CHECK_TYPEDEF has already been done. */
71 gccgo_string_p (struct type *type)
73 /* gccgo strings don't necessarily have a name we can use. */
75 if (TYPE_NFIELDS (type) == 2)
77 struct type *type0 = TYPE_FIELD_TYPE (type, 0);
78 struct type *type1 = TYPE_FIELD_TYPE (type, 1);
80 type0 = check_typedef (type0);
81 type1 = check_typedef (type1);
83 if (TYPE_CODE (type0) == TYPE_CODE_PTR
84 && strcmp (TYPE_FIELD_NAME (type, 0), "__data") == 0
85 && TYPE_CODE (type1) == TYPE_CODE_INT
86 && strcmp (TYPE_FIELD_NAME (type, 1), "__length") == 0)
88 struct type *target_type = TYPE_TARGET_TYPE (type0);
90 target_type = check_typedef (target_type);
92 if (TYPE_CODE (target_type) == TYPE_CODE_INT
93 && TYPE_LENGTH (target_type) == 1
94 && strcmp (TYPE_NAME (target_type), "uint8") == 0)
102 /* Return non-zero if TYPE is a 6g string.
103 We assume CHECK_TYPEDEF has already been done. */
106 sixg_string_p (struct type *type)
108 if (TYPE_NFIELDS (type) == 2
109 && TYPE_NAME (type) != NULL
110 && strcmp (TYPE_NAME (type), "string") == 0)
116 /* Classify the kind of Go object that TYPE is.
117 TYPE is a TYPE_CODE_STRUCT, used to represent a Go object. */
120 go_classify_struct_type (struct type *type)
122 type = check_typedef (type);
124 /* Recognize strings as they're useful to be able to print without
126 if (gccgo_string_p (type)
127 || sixg_string_p (type))
128 return GO_TYPE_STRING;
133 /* Subroutine of unpack_mangled_go_symbol to simplify it.
134 Given "[foo.]bar.baz", store "bar" in *PACKAGEP and "baz" in *OBJECTP.
135 We stomp on the last '.' to nul-terminate "bar".
136 The caller is responsible for memory management. */
139 unpack_package_and_object (char *buf,
140 const char **packagep, const char **objectp)
144 last_dot = strrchr (buf, '.');
145 gdb_assert (last_dot != NULL);
146 *objectp = last_dot + 1;
148 last_dot = strrchr (buf, '.');
149 if (last_dot != NULL)
150 *packagep = last_dot + 1;
155 /* Given a mangled Go symbol, find its package name, object name, and
156 method type (if present).
157 E.g., for "libgo_net.textproto.String.N33_libgo_net.textproto.ProtocolError"
158 *PACKAGEP = "textproto"
160 *METHOD_TYPE_PACKAGEP = "textproto"
161 *METHOD_TYPE_OBJECTP = "ProtocolError"
163 Space for the resulting strings is malloc'd in one buffer.
164 PACKAGEP,OBJECTP,METHOD_TYPE* will (typically) point into this buffer.
165 [There are a few exceptions, but the caller is still responsible for
166 freeing the resulting pointer.]
167 A pointer to this buffer is returned, or NULL if symbol isn't a
169 The caller is responsible for freeing the result.
171 *METHOD_TYPE_IS_POINTERP is set to a boolean indicating if
172 the method type is a pointer.
174 There may be value in returning the outer container,
175 i.e., "net" in the above example, but for now it's not needed.
176 Plus it's currently not straightforward to compute,
177 it comes from -fgo-prefix, and there's no algorithm to compute it.
179 If we ever need to unpack the method type, this routine should work
183 unpack_mangled_go_symbol (const char *mangled_name,
184 const char **packagep,
185 const char **objectp,
186 const char **method_type_packagep,
187 const char **method_type_objectp,
188 int *method_type_is_pointerp)
192 int len = strlen (mangled_name);
193 /* Pointer to last digit in "N<digit(s)>_". */
195 /* Pointer to "N" if valid "N<digit(s)>_" found. */
197 /* Pointer to the first '.'. */
198 const char *first_dot;
199 /* Pointer to the last '.'. */
200 const char *last_dot;
201 /* Non-zero if we saw a pointer indicator. */
204 *packagep = *objectp = NULL;
205 *method_type_packagep = *method_type_objectp = NULL;
206 *method_type_is_pointerp = 0;
208 /* main.init is mangled specially. */
209 if (strcmp (mangled_name, "__go_init_main") == 0)
211 char *package = xstrdup ("main");
218 /* main.main is mangled specially (missing prefix). */
219 if (strcmp (mangled_name, "main.main") == 0)
221 char *package = xstrdup ("main");
228 /* We may get passed, e.g., "main.T.Foo", which is *not* mangled.
229 Alas it looks exactly like "prefix.package.object."
230 To cope for now we only recognize the following prefixes:
233 libgo_.*: used by gccgo's runtime
235 Thus we don't support -fgo-prefix (except as used by the runtime). */
236 if (!startswith (mangled_name, "go.")
237 && !startswith (mangled_name, "libgo_"))
240 /* Quick check for whether a search may be fruitful. */
241 /* Ignore anything with @plt, etc. in it. */
242 if (strchr (mangled_name, '@') != NULL)
244 /* It must have at least two dots. */
245 first_dot = strchr (mangled_name, '.');
246 if (first_dot == NULL)
248 /* Treat "foo.bar" as unmangled. It can collide with lots of other
249 languages and it's not clear what the consequences are.
250 And except for main.main, all gccgo symbols are at least
251 prefix.package.object. */
252 last_dot = strrchr (mangled_name, '.');
253 if (last_dot == first_dot)
256 /* More quick checks. */
257 if (last_dot[1] == '\0' /* foo. */
258 || last_dot[-1] == '.') /* foo..bar */
261 /* At this point we've decided we have a mangled Go symbol. */
263 buf = xstrdup (mangled_name);
265 /* Search backwards looking for "N<digit(s)>". */
267 saw_digit = method_type = NULL;
271 int current = *(const unsigned char *) --p;
272 int current_is_digit = isdigit (current);
276 if (current_is_digit)
279 && ((p > buf && p[-1] == '.')
280 || (p > buf + 1 && p[-1] == 'p' && p[-2] == '.')))
282 if (atoi (p + 1) == strlen (saw_digit + 2))
288 gdb_assert (p[-1] == 'p');
295 /* Not what we're looking for, reset and keep looking. */
300 if (current_is_digit && p[1] == '_')
302 /* Possible start of method "this" [sic] type. */
308 if (method_type != NULL
309 /* Ensure not something like "..foo". */
310 && (method_type > buf && method_type[-1] != '.'))
312 unpack_package_and_object (saw_digit + 2,
313 method_type_packagep, method_type_objectp);
315 *method_type_is_pointerp = saw_pointer;
318 unpack_package_and_object (buf, packagep, objectp);
322 /* Implements the la_demangle language_defn routine for language Go.
324 N.B. This may get passed *any* symbol, including symbols from other
325 languages and including symbols that are already demangled.
326 Both of these situations are kinda unfortunate, but that's how things
329 N.B. This currently only supports gccgo's mangling.
331 N.B. gccgo's mangling needs, I think, changing.
332 This demangler can't work in all situations,
333 thus not too much effort is currently put into it. */
336 go_demangle (const char *mangled_name, int options)
338 struct obstack tempbuf;
341 const char *package_name;
342 const char *object_name;
343 const char *method_type_package_name;
344 const char *method_type_object_name;
345 int method_type_is_pointer;
347 if (mangled_name == NULL)
350 name_buf = unpack_mangled_go_symbol (mangled_name,
351 &package_name, &object_name,
352 &method_type_package_name,
353 &method_type_object_name,
354 &method_type_is_pointer);
355 if (name_buf == NULL)
358 obstack_init (&tempbuf);
360 /* Print methods as they appear in "method expressions". */
361 if (method_type_package_name != NULL)
363 /* FIXME: Seems like we should include package_name here somewhere. */
364 if (method_type_is_pointer)
365 obstack_grow_str (&tempbuf, "(*");
366 obstack_grow_str (&tempbuf, method_type_package_name);
367 obstack_grow_str (&tempbuf, ".");
368 obstack_grow_str (&tempbuf, method_type_object_name);
369 if (method_type_is_pointer)
370 obstack_grow_str (&tempbuf, ")");
371 obstack_grow_str (&tempbuf, ".");
372 obstack_grow_str (&tempbuf, object_name);
376 obstack_grow_str (&tempbuf, package_name);
377 obstack_grow_str (&tempbuf, ".");
378 obstack_grow_str (&tempbuf, object_name);
380 obstack_grow_str0 (&tempbuf, "");
382 result = xstrdup ((const char *) obstack_finish (&tempbuf));
383 obstack_free (&tempbuf, NULL);
388 /* la_sniff_from_mangled_name for Go. */
391 go_sniff_from_mangled_name (const char *mangled, char **demangled)
393 *demangled = go_demangle (mangled, 0);
394 return *demangled != NULL;
397 /* Given a Go symbol, return its package or NULL if unknown.
398 Space for the result is malloc'd, caller must free. */
401 go_symbol_package_name (const struct symbol *sym)
403 const char *mangled_name = SYMBOL_LINKAGE_NAME (sym);
404 const char *package_name;
405 const char *object_name;
406 const char *method_type_package_name;
407 const char *method_type_object_name;
408 int method_type_is_pointer;
412 gdb_assert (SYMBOL_LANGUAGE (sym) == language_go);
413 name_buf = unpack_mangled_go_symbol (mangled_name,
414 &package_name, &object_name,
415 &method_type_package_name,
416 &method_type_object_name,
417 &method_type_is_pointer);
418 /* Some Go symbols don't have mangled form we interpret (yet). */
419 if (name_buf == NULL)
421 result = xstrdup (package_name);
426 /* Return the package that BLOCK is in, or NULL if there isn't one.
427 Space for the result is malloc'd, caller must free. */
430 go_block_package_name (const struct block *block)
432 while (block != NULL)
434 struct symbol *function = BLOCK_FUNCTION (block);
436 if (function != NULL)
438 char *package_name = go_symbol_package_name (function);
440 if (package_name != NULL)
443 /* Stop looking if we find a function without a package name.
444 We're most likely outside of Go and thus the concept of the
445 "current" package is gone. */
449 block = BLOCK_SUPERBLOCK (block);
455 /* Table mapping opcodes into strings for printing operators
456 and precedences of the operators.
459 static const struct op_print go_op_print_tab[] =
461 {",", BINOP_COMMA, PREC_COMMA, 0},
462 {"=", BINOP_ASSIGN, PREC_ASSIGN, 1},
463 {"||", BINOP_LOGICAL_OR, PREC_LOGICAL_OR, 0},
464 {"&&", BINOP_LOGICAL_AND, PREC_LOGICAL_AND, 0},
465 {"|", BINOP_BITWISE_IOR, PREC_BITWISE_IOR, 0},
466 {"^", BINOP_BITWISE_XOR, PREC_BITWISE_XOR, 0},
467 {"&", BINOP_BITWISE_AND, PREC_BITWISE_AND, 0},
468 {"==", BINOP_EQUAL, PREC_EQUAL, 0},
469 {"!=", BINOP_NOTEQUAL, PREC_EQUAL, 0},
470 {"<=", BINOP_LEQ, PREC_ORDER, 0},
471 {">=", BINOP_GEQ, PREC_ORDER, 0},
472 {">", BINOP_GTR, PREC_ORDER, 0},
473 {"<", BINOP_LESS, PREC_ORDER, 0},
474 {">>", BINOP_RSH, PREC_SHIFT, 0},
475 {"<<", BINOP_LSH, PREC_SHIFT, 0},
476 {"+", BINOP_ADD, PREC_ADD, 0},
477 {"-", BINOP_SUB, PREC_ADD, 0},
478 {"*", BINOP_MUL, PREC_MUL, 0},
479 {"/", BINOP_DIV, PREC_MUL, 0},
480 {"%", BINOP_REM, PREC_MUL, 0},
481 {"@", BINOP_REPEAT, PREC_REPEAT, 0},
482 {"-", UNOP_NEG, PREC_PREFIX, 0},
483 {"!", UNOP_LOGICAL_NOT, PREC_PREFIX, 0},
484 {"^", UNOP_COMPLEMENT, PREC_PREFIX, 0},
485 {"*", UNOP_IND, PREC_PREFIX, 0},
486 {"&", UNOP_ADDR, PREC_PREFIX, 0},
487 {"unsafe.Sizeof ", UNOP_SIZEOF, PREC_PREFIX, 0},
488 {"++", UNOP_POSTINCREMENT, PREC_SUFFIX, 0},
489 {"--", UNOP_POSTDECREMENT, PREC_SUFFIX, 0},
490 {NULL, OP_NULL, PREC_SUFFIX, 0}
493 enum go_primitive_types {
494 go_primitive_type_void,
495 go_primitive_type_char,
496 go_primitive_type_bool,
497 go_primitive_type_int,
498 go_primitive_type_uint,
499 go_primitive_type_uintptr,
500 go_primitive_type_int8,
501 go_primitive_type_int16,
502 go_primitive_type_int32,
503 go_primitive_type_int64,
504 go_primitive_type_uint8,
505 go_primitive_type_uint16,
506 go_primitive_type_uint32,
507 go_primitive_type_uint64,
508 go_primitive_type_float32,
509 go_primitive_type_float64,
510 go_primitive_type_complex64,
511 go_primitive_type_complex128,
512 nr_go_primitive_types
516 go_language_arch_info (struct gdbarch *gdbarch,
517 struct language_arch_info *lai)
519 const struct builtin_go_type *builtin = builtin_go_type (gdbarch);
521 lai->string_char_type = builtin->builtin_char;
523 lai->primitive_type_vector
524 = GDBARCH_OBSTACK_CALLOC (gdbarch, nr_go_primitive_types + 1,
527 lai->primitive_type_vector [go_primitive_type_void]
528 = builtin->builtin_void;
529 lai->primitive_type_vector [go_primitive_type_char]
530 = builtin->builtin_char;
531 lai->primitive_type_vector [go_primitive_type_bool]
532 = builtin->builtin_bool;
533 lai->primitive_type_vector [go_primitive_type_int]
534 = builtin->builtin_int;
535 lai->primitive_type_vector [go_primitive_type_uint]
536 = builtin->builtin_uint;
537 lai->primitive_type_vector [go_primitive_type_uintptr]
538 = builtin->builtin_uintptr;
539 lai->primitive_type_vector [go_primitive_type_int8]
540 = builtin->builtin_int8;
541 lai->primitive_type_vector [go_primitive_type_int16]
542 = builtin->builtin_int16;
543 lai->primitive_type_vector [go_primitive_type_int32]
544 = builtin->builtin_int32;
545 lai->primitive_type_vector [go_primitive_type_int64]
546 = builtin->builtin_int64;
547 lai->primitive_type_vector [go_primitive_type_uint8]
548 = builtin->builtin_uint8;
549 lai->primitive_type_vector [go_primitive_type_uint16]
550 = builtin->builtin_uint16;
551 lai->primitive_type_vector [go_primitive_type_uint32]
552 = builtin->builtin_uint32;
553 lai->primitive_type_vector [go_primitive_type_uint64]
554 = builtin->builtin_uint64;
555 lai->primitive_type_vector [go_primitive_type_float32]
556 = builtin->builtin_float32;
557 lai->primitive_type_vector [go_primitive_type_float64]
558 = builtin->builtin_float64;
559 lai->primitive_type_vector [go_primitive_type_complex64]
560 = builtin->builtin_complex64;
561 lai->primitive_type_vector [go_primitive_type_complex128]
562 = builtin->builtin_complex128;
564 lai->bool_type_symbol = "bool";
565 lai->bool_type_default = builtin->builtin_bool;
568 extern const struct language_defn go_language_defn =
581 c_printchar, /* Print a character constant. */
582 c_printstr, /* Function to print string constant. */
583 c_emit_char, /* Print a single char. */
584 go_print_type, /* Print a type using appropriate syntax. */
585 c_print_typedef, /* Print a typedef using appropriate
587 go_val_print, /* Print a value using appropriate syntax. */
588 c_value_print, /* Print a top-level value. */
589 default_read_var_value, /* la_read_var_value */
590 NULL, /* Language specific skip_trampoline. */
591 NULL, /* name_of_this */
592 false, /* la_store_sym_names_in_linkage_form_p */
593 basic_lookup_symbol_nonlocal,
594 basic_lookup_transparent_type,
595 go_demangle, /* Language specific symbol demangler. */
596 go_sniff_from_mangled_name,
597 NULL, /* Language specific
598 class_name_from_physname. */
599 go_op_print_tab, /* Expression operators for printing. */
600 1, /* C-style arrays. */
601 0, /* String lower bound. */
602 default_word_break_characters,
603 default_collect_symbol_completion_matches,
604 go_language_arch_info,
605 default_print_array_index,
606 default_pass_by_reference,
608 c_watch_location_expression,
609 NULL, /* la_get_symbol_name_matcher */
610 iterate_over_symbols,
611 default_search_name_hash,
615 "{...}" /* la_struct_too_deep_ellipsis */
619 build_go_types (struct gdbarch *gdbarch)
621 struct builtin_go_type *builtin_go_type
622 = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct builtin_go_type);
624 builtin_go_type->builtin_void
625 = arch_type (gdbarch, TYPE_CODE_VOID, TARGET_CHAR_BIT, "void");
626 builtin_go_type->builtin_char
627 = arch_character_type (gdbarch, 8, 1, "char");
628 builtin_go_type->builtin_bool
629 = arch_boolean_type (gdbarch, 8, 0, "bool");
630 builtin_go_type->builtin_int
631 = arch_integer_type (gdbarch, gdbarch_int_bit (gdbarch), 0, "int");
632 builtin_go_type->builtin_uint
633 = arch_integer_type (gdbarch, gdbarch_int_bit (gdbarch), 1, "uint");
634 builtin_go_type->builtin_uintptr
635 = arch_integer_type (gdbarch, gdbarch_ptr_bit (gdbarch), 1, "uintptr");
636 builtin_go_type->builtin_int8
637 = arch_integer_type (gdbarch, 8, 0, "int8");
638 builtin_go_type->builtin_int16
639 = arch_integer_type (gdbarch, 16, 0, "int16");
640 builtin_go_type->builtin_int32
641 = arch_integer_type (gdbarch, 32, 0, "int32");
642 builtin_go_type->builtin_int64
643 = arch_integer_type (gdbarch, 64, 0, "int64");
644 builtin_go_type->builtin_uint8
645 = arch_integer_type (gdbarch, 8, 1, "uint8");
646 builtin_go_type->builtin_uint16
647 = arch_integer_type (gdbarch, 16, 1, "uint16");
648 builtin_go_type->builtin_uint32
649 = arch_integer_type (gdbarch, 32, 1, "uint32");
650 builtin_go_type->builtin_uint64
651 = arch_integer_type (gdbarch, 64, 1, "uint64");
652 builtin_go_type->builtin_float32
653 = arch_float_type (gdbarch, 32, "float32", floatformats_ieee_single);
654 builtin_go_type->builtin_float64
655 = arch_float_type (gdbarch, 64, "float64", floatformats_ieee_double);
656 builtin_go_type->builtin_complex64
657 = arch_complex_type (gdbarch, "complex64",
658 builtin_go_type->builtin_float32);
659 builtin_go_type->builtin_complex128
660 = arch_complex_type (gdbarch, "complex128",
661 builtin_go_type->builtin_float64);
663 return builtin_go_type;
666 static struct gdbarch_data *go_type_data;
668 const struct builtin_go_type *
669 builtin_go_type (struct gdbarch *gdbarch)
671 return (const struct builtin_go_type *) gdbarch_data (gdbarch, go_type_data);
675 _initialize_go_language (void)
677 go_type_data = gdbarch_data_register_post_init (build_go_types);