X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Flanguage.h;h=05ad132d01b5ffee9715849f525fdbc14d50890b;hb=refs%2Fheads%2Fconcurrent-displaced-stepping-2020-04-01;hp=34f569227beb3e45ee149d626aca34723eca8273;hpb=b5ec771e60c1a0863e51eb491c85c674097e9e13;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/language.h b/gdb/language.h index 34f569227b..05ad132d01 100644 --- a/gdb/language.h +++ b/gdb/language.h @@ -1,6 +1,6 @@ /* Source-language-related definitions for GDB. - Copyright (C) 1991-2017 Free Software Foundation, Inc. + Copyright (C) 1991-2020 Free Software Foundation, Inc. Contributed by the Department of Computer Science at the State University of New York at Buffalo. @@ -24,19 +24,21 @@ #define LANGUAGE_H 1 #include "symtab.h" -#include "common/function-view.h" +#include "gdbsupport/function-view.h" +#include "expression.h" /* Forward decls for prototypes. */ struct value; struct objfile; struct frame_info; -struct expression; struct ui_file; struct value_print_options; struct type_print_options; struct lang_varobj_ops; struct parser_state; -struct compile_instance; +class compile_instance; +struct completion_match_for_lcd; +class innermost_block_tracker; #define MAX_FORTRAN_DIMS 7 /* Maximum number of F77 array dims. */ @@ -126,9 +128,62 @@ struct language_arch_info struct type *bool_type_default; }; -/* Structure tying together assorted information about a language. */ +/* In a language (particularly C++) a function argument of an aggregate + type (i.e. class/struct/union) may be implicitly passed by reference + even though it is declared a call-by-value argument in the source. + The struct below puts together necessary information for GDB to be + able to detect and carry out pass-by-reference semantics for a + particular type. This type is referred as T in the inlined comments + below. -struct language_defn + The default values of the fields are chosen to give correct semantics + for primitive types and for simple aggregate types, such as + + class T { + int x; + }; */ + +struct language_pass_by_ref_info +{ + /* True if an argument of type T can be passed to a function by value + (i.e. not through an implicit reference). False, otherwise. */ + bool trivially_copyable = true; + + /* True if a copy of a value of type T can be initialized by + memcpy'ing the value bit-by-bit. False, otherwise. + E.g. If T has a user-defined copy ctor, this should be false. */ + bool trivially_copy_constructible = true; + + /* True if a value of type T can be destructed simply by reclaiming + the memory area occupied by the value. False, otherwise. + E.g. If T has a user-defined destructor, this should be false. */ + bool trivially_destructible = true; + + /* True if it is allowed to create a copy of a value of type T. + False, otherwise. + E.g. If T has a deleted copy ctor, this should be false. */ + bool copy_constructible = true; + + /* True if a value of type T can be destructed. False, otherwise. + E.g. If T has a deleted destructor, this should be false. */ + bool destructible = true; +}; + +/* Structure tying together assorted information about a language. + + As we move over from the old structure based languages to a class + hierarchy of languages this structure will continue to contain a + mixture of both data and function pointers. + + Once the class hierarchy of languages in place the first task is to + remove the function pointers from this structure and convert them into + member functions on the different language classes. + + The current plan it to keep the constant data that describes a language + in this structure, and have each language pass in an instance of this + structure at construction time. */ + +struct language_data { /* Name of the language. */ @@ -171,17 +226,16 @@ struct language_defn int (*la_parser) (struct parser_state *); - /* Parser error function. */ - - void (*la_error) (const char *); - /* Given an expression *EXPP created by prefixifying the result of la_parser, perform any remaining processing necessary to complete its translation. *EXPP may change; la_post_parser is responsible for releasing its previous contents, if necessary. If - VOID_CONTEXT_P, then no value is expected from the expression. */ + VOID_CONTEXT_P, then no value is expected from the expression. + If COMPLETING is non-zero, then the expression has been parsed + for completion, not evaluation. */ - void (*la_post_parser) (struct expression ** expp, int void_context_p); + void (*la_post_parser) (expression_up *expp, int void_context_p, + int completing, innermost_block_tracker *tracker); void (*la_printchar) (int ch, struct type *chtype, struct ui_file * stream); @@ -194,11 +248,6 @@ struct language_defn void (*la_emitchar) (int ch, struct type *chtype, struct ui_file * stream, int quoter); - /* Print a type using syntax appropriate for this language. */ - - void (*la_print_type) (struct type *, const char *, struct ui_file *, int, - int, const struct type_print_options *); - /* Print a typedef using syntax appropriate for this language. TYPE is the underlying type. NEW_SYMBOL is the symbol naming the type. STREAM is the output stream on which to print. */ @@ -207,61 +256,43 @@ struct language_defn struct ui_file *stream); /* Print a value using syntax appropriate for this language. - - TYPE is the type of the sub-object to be printed. - - EMBEDDED_OFFSET is the offset into the outermost object of the - sub-object represented by TYPE. This is the object which this - call should print. Note that the enclosing type is not - available. - - ADDRESS is the address in the inferior of the enclosing object. + RECURSE is the recursion depth. It is zero-based. */ - STREAM is the stream on which the value is to be printed. - - RECURSE is the recursion depth. It is zero-based. - - OPTIONS are the formatting options to be used when - printing. */ - - void (*la_val_print) (struct type *type, - int embedded_offset, CORE_ADDR address, - struct ui_file *stream, int recurse, - struct value *val, - const struct value_print_options *options); + void (*la_value_print_inner) (struct value *, struct ui_file *, + int recurse, + const struct value_print_options *); /* Print a top-level value using syntax appropriate for this language. */ void (*la_value_print) (struct value *, struct ui_file *, const struct value_print_options *); - /* Given a symbol VAR, the corresponding block VAR_BLOCK (if any) and a - stack frame id FRAME, read the value of the variable and return (pointer - to a) struct value containing the value. + /* Now come some hooks for lookup_symbol. */ - VAR_BLOCK is needed if there's a possibility for VAR to be outside - FRAME. This is what happens if FRAME correspond to a nested function - and VAR is defined in the outer function. If callers know that VAR is - located in FRAME or is global/static, NULL can be passed as VAR_BLOCK. + /* If this is non-NULL, specifies the name that of the implicit + local variable that refers to the current object instance. */ - Throw an error if the variable cannot be found. */ + const char *la_name_of_this; - struct value *(*la_read_var_value) (struct symbol *var, - const struct block *var_block, - struct frame_info *frame); + /* True if the symbols names should be stored in GDB's data structures + for minimal/partial/full symbols using their linkage (aka mangled) + form; false if the symbol names should be demangled first. - /* PC is possibly an unknown languages trampoline. - If that PC falls in a trampoline belonging to this language, - return the address of the first pc in the real function, or 0 - if it isn't a language tramp for this language. */ - CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR); + Most languages implement symbol lookup by comparing the demangled + names, in which case it is advantageous to store that information + already demangled, and so would set this field to false. - /* Now come some hooks for lookup_symbol. */ + On the other hand, some languages have opted for doing symbol + lookups by comparing mangled names instead, for reasons usually + specific to the language. Those languages should set this field + to true. - /* If this is non-NULL, specifies the name that of the implicit - local variable that refers to the current object instance. */ + And finally, other languages such as C or Asm do not have + the concept of mangled vs demangled name, so those languages + should set this field to true as well, to prevent any accidental + demangling through an unrelated language's demangler. */ - const char *la_name_of_this; + const bool la_store_sym_names_in_linkage_form_p; /* This is a function that lookup_symbol will call when it gets to the part of symbol lookup where C looks up static and global @@ -273,28 +304,6 @@ struct language_defn const struct block *, const domain_enum); - /* Find the definition of the type with the given name. */ - struct type *(*la_lookup_transparent_type) (const char *); - - /* Return demangled language symbol, or NULL. */ - char *(*la_demangle) (const char *mangled, int options); - - /* Demangle a symbol according to this language's rules. Unlike - la_demangle, this does not take any options. - - *DEMANGLED will be set by this function. - - If this function returns 0, then *DEMANGLED must always be set - to NULL. - - If this function returns 1, the implementation may set this to - a xmalloc'd string holding the demangled form. However, it is - not required to. The string, if any, is owned by the caller. - - The resulting string should be of the form that will be - installed into a symbol. */ - int (*la_sniff_from_mangled_name) (const char *mangled, char **demangled); - /* Return class name of a mangled method name or NULL. */ char *(*la_class_name_from_physname) (const char *physname); @@ -326,32 +335,6 @@ struct language_defn const char *word, enum type_code code); - /* The per-architecture (OS/ABI) language information. */ - void (*la_language_arch_info) (struct gdbarch *, - struct language_arch_info *); - - /* Print the index of an element of an array. */ - void (*la_print_array_index) (struct value *index_value, - struct ui_file *stream, - const struct value_print_options *options); - - /* Return non-zero if TYPE should be passed (and returned) by - reference at the language level. */ - int (*la_pass_by_reference) (struct type *type); - - /* Obtain a string from the inferior, storing it in a newly allocated - buffer in BUFFER, which should be freed by the caller. If the - in- and out-parameter *LENGTH is specified at -1, the string is - read until a null character of the appropriate width is found - - otherwise the string is read to the length of characters specified. - On completion, *LENGTH will hold the size of the string in characters. - If a *LENGTH of -1 was specified it will count only actual - characters, excluding any eventual terminating null character. - Otherwise *LENGTH will include all characters - including any nulls. - CHARSET will hold the encoding used in the string. */ - void (*la_get_string) (struct value *value, gdb_byte **buffer, int *length, - struct type **chartype, const char **charset); - /* Return an expression that can be used for a location watchpoint. TYPE is a pointer type that points to the memory to watch, and ADDR is the address of the watched memory. */ @@ -371,42 +354,9 @@ struct language_defn symbol_name_matcher_ftype *(*la_get_symbol_name_matcher) (const lookup_name_info &); - /* Find all symbols in the current program space matching NAME in - DOMAIN, according to this language's rules. - - The search is done in BLOCK only. - The caller is responsible for iterating up through superblocks - if desired. - - For each one, call CALLBACK with the symbol. If CALLBACK - returns false, the iteration ends at that point. - - This field may not be NULL. If the language does not need any - special processing here, 'iterate_over_symbols' should be - used as the definition. */ - void (*la_iterate_over_symbols) - (const struct block *block, const lookup_name_info &name, - domain_enum domain, - gdb::function_view callback); - - /* Hash the given symbol search name. Use - default_search_name_hash if no special treatment is - required. */ - unsigned int (*la_search_name_hash) (const char *name); - /* Various operations on varobj. */ const struct lang_varobj_ops *la_varobj_ops; - /* If this language allows compilation from the gdb command line, - this method should be non-NULL. When called it should return - an instance of struct gcc_context appropriate to the language. - When defined this method must never return NULL; instead it - should throw an exception on failure. The returned compiler - instance is owned by its caller and must be deallocated by - calling its 'destroy' method. */ - - struct compile_instance *(*la_get_compile_instance) (void); - /* This method must be defined if 'la_get_gcc_context' is defined. If 'la_get_gcc_context' is not defined, then this method is ignored. @@ -421,20 +371,161 @@ struct language_defn parsed. EXPR_PC is the PC at which the expression is being parsed. */ - std::string (*la_compute_program) (struct compile_instance *inst, + std::string (*la_compute_program) (compile_instance *inst, const char *input, struct gdbarch *gdbarch, const struct block *expr_block, CORE_ADDR expr_pc); - /* Add fields above this point, so the magic number is always last. */ - /* Magic number for compat checking. */ + /* Return true if TYPE is a string type. */ + bool (*la_is_string_type_p) (struct type *type); - long la_magic; + /* This string is used by the 'set print max-depth' setting. When GDB + replaces a struct or union (during value printing) that is "too + deep" this string is displayed instead. */ + const char *la_struct_too_deep_ellipsis; }; -#define LANG_MAGIC 910823L +/* Base class from which all other language classes derive. */ + +struct language_defn : language_data +{ + language_defn (enum language lang, const language_data &init_data) + : language_data (init_data) + { + /* We should only ever create one instance of each language. */ + gdb_assert (languages[lang] == nullptr); + languages[lang] = this; + } + + /* Print the index of an element of an array. This default + implementation prints using C99 syntax. */ + + virtual void print_array_index (struct type *index_type, + LONGEST index_value, + struct ui_file *stream, + const value_print_options *options) const; + + /* Given a symbol VAR, the corresponding block VAR_BLOCK (if any) and a + stack frame id FRAME, read the value of the variable and return (pointer + to a) struct value containing the value. + + VAR_BLOCK is needed if there's a possibility for VAR to be outside + FRAME. This is what happens if FRAME correspond to a nested function + and VAR is defined in the outer function. If callers know that VAR is + located in FRAME or is global/static, NULL can be passed as VAR_BLOCK. + + Throw an error if the variable cannot be found. */ + + virtual struct value *read_var_value (struct symbol *var, + const struct block *var_block, + struct frame_info *frame) const; + + /* Return information about whether TYPE should be passed + (and returned) by reference at the language level. The default + implementation returns a LANGUAGE_PASS_BY_REF_INFO initialised in its + default state. */ + + virtual struct language_pass_by_ref_info pass_by_reference_info + (struct type *type) const + { + return {}; + } + + /* The per-architecture (OS/ABI) language information. */ + + virtual void language_arch_info (struct gdbarch *, + struct language_arch_info *) const = 0; + + /* Find the definition of the type with the given name. */ + + virtual struct type *lookup_transparent_type (const char *name) const + { + return basic_lookup_transparent_type (name); + } + + /* Find all symbols in the current program space matching NAME in + DOMAIN, according to this language's rules. + + The search is done in BLOCK only. + The caller is responsible for iterating up through superblocks + if desired. + + For each one, call CALLBACK with the symbol. If CALLBACK + returns false, the iteration ends at that point. + + This field may not be NULL. If the language does not need any + special processing here, 'iterate_over_symbols' should be + used as the definition. */ + virtual bool iterate_over_symbols + (const struct block *block, const lookup_name_info &name, + domain_enum domain, + gdb::function_view callback) const + { + return ::iterate_over_symbols (block, name, domain, callback); + } + + /* If this language allows compilation from the gdb command line, then + this method will return an instance of struct gcc_context appropriate + to the language. If compilation for this language is generally + supported, but something goes wrong then an exception is thrown. The + returned compiler instance is owned by its caller and must be + deallocated by the caller. If compilation is not supported for this + language then this method returns NULL. */ + + virtual compile_instance *get_compile_instance () const + { + return nullptr; + } + + /* Hash the given symbol search name. */ + virtual unsigned int search_name_hash (const char *name) const; + + /* Demangle a symbol according to this language's rules. Unlike + la_demangle, this does not take any options. + + *DEMANGLED will be set by this function. + + If this function returns false, then *DEMANGLED must always be set + to NULL. + + If this function returns true, the implementation may set this to + a xmalloc'd string holding the demangled form. However, it is + not required to. The string, if any, is owned by the caller. + + The resulting string should be of the form that will be + installed into a symbol. */ + virtual bool sniff_from_mangled_name (const char *mangled, + char **demangled) const + { + *demangled = nullptr; + return false; + } + + /* Return demangled language symbol version of MANGLED, or NULL. */ + virtual char *demangle (const char *mangled, int options) const + { + return nullptr; + } + + /* Print a type using syntax appropriate for this language. */ + + virtual void print_type (struct type *, const char *, struct ui_file *, int, + int, const struct type_print_options *) const = 0; + + /* PC is possibly an unknown languages trampoline. + If that PC falls in a trampoline belonging to this language, return + the address of the first pc in the real function, or 0 if it isn't a + language tramp for this language. */ + virtual CORE_ADDR skip_trampoline (struct frame_info *fi, CORE_ADDR pc) const + { + return (CORE_ADDR) 0; + } + + /* List of all known languages. */ + static const struct language_defn *languages[nr_languages]; +}; /* Pointer to the language_defn for our current language. This pointer always points to *some* valid struct; it can be used without checking @@ -459,6 +550,11 @@ extern const struct language_defn *current_language; extern const struct language_defn *expected_language; +/* Warning issued when current_language and the language of the current + frame do not match. */ + +extern const char lang_frame_mismatch_warn[]; + /* language_mode == language_mode_auto: current_language automatically set upon selection of scope (e.g. stack frame) @@ -515,7 +611,7 @@ extern enum language set_language (enum language); with the "set language" command. */ #define LA_PRINT_TYPE(type,varstring,stream,show,level,flags) \ - (current_language->la_print_type(type,varstring,stream,show,level,flags)) + (current_language->print_type(type,varstring,stream,show,level,flags)) #define LA_PRINT_TYPEDEF(type,new_symbol,stream) \ (current_language->la_print_typedef(type,new_symbol,stream)) @@ -530,14 +626,13 @@ extern enum language set_language (enum language); encoding, force_ellipses,options)) #define LA_EMIT_CHAR(ch, type, stream, quoter) \ (current_language->la_emitchar(ch, type, stream, quoter)) -#define LA_GET_STRING(value, buffer, length, chartype, encoding) \ - (current_language->la_get_string(value, buffer, length, chartype, encoding)) -#define LA_PRINT_ARRAY_INDEX(index_value, stream, options) \ - (current_language->la_print_array_index(index_value, stream, options)) +#define LA_PRINT_ARRAY_INDEX(index_type, index_value, stream, options) \ + (current_language->print_array_index(index_type, index_value, stream, \ + options)) #define LA_ITERATE_OVER_SYMBOLS(BLOCK, NAME, DOMAIN, CALLBACK) \ - (current_language->la_iterate_over_symbols (BLOCK, NAME, DOMAIN, CALLBACK)) + (current_language->iterate_over_symbols (BLOCK, NAME, DOMAIN, CALLBACK)) /* Test a character to decide whether it can be printed in literal form or needs to be printed in another representation. For example, @@ -554,6 +649,10 @@ extern enum language set_language (enum language); extern int pointer_type (struct type *); +/* Return true if TYPE is a string type, otherwise return false. This + default implementation only detects TYPE_CODE_STRING. */ +extern bool default_is_string_type_p (struct type *type); + /* Error messages */ extern void range_error (const char *, ...) ATTRIBUTE_PRINTF (1, 2); @@ -578,13 +677,6 @@ extern CORE_ADDR skip_language_trampoline (struct frame_info *, CORE_ADDR pc); extern char *language_demangle (const struct language_defn *current_language, const char *mangled, int options); -/* A wrapper for la_sniff_from_mangled_name. The arguments and result - are as for the method. */ - -extern int language_sniff_from_mangled_name (const struct language_defn *lang, - const char *mangled, - char **demangled); - /* Return class name from physname, or NULL. */ extern char *language_class_name_from_physname (const struct language_defn *, const char *physname); @@ -592,69 +684,34 @@ extern char *language_class_name_from_physname (const struct language_defn *, /* Splitting strings into words. */ extern const char *default_word_break_characters (void); -/* Print the index of an array element using the C99 syntax. */ -extern void default_print_array_index (struct value *index_value, - struct ui_file *stream, - const struct value_print_options *options); - -/* Return non-zero if TYPE should be passed (and returned) by - reference at the language level. */ -int language_pass_by_reference (struct type *type); - -/* Return zero; by default, types are passed by value at the language - level. The target ABI may pass or return some structs by reference - independent of this. */ -int default_pass_by_reference (struct type *type); +/* Return information about whether TYPE should be passed + (and returned) by reference at the language level. */ +struct language_pass_by_ref_info language_pass_by_reference (struct type *type); /* The default implementation of la_print_typedef. */ void default_print_typedef (struct type *type, struct symbol *new_symbol, struct ui_file *stream); -void default_get_string (struct value *value, gdb_byte **buffer, int *length, - struct type **char_type, const char **charset); - -/* Default name hashing function. */ - -/* Produce an unsigned hash value from SEARCH_NAME that is consistent - with strcmp_iw, strcmp, and, at least on Ada symbols, wild_match. - That is, two identifiers equivalent according to any of those three - comparison operators hash to the same value. */ -extern unsigned int default_search_name_hash (const char *search_name); - -void c_get_string (struct value *value, gdb_byte **buffer, int *length, - struct type **char_type, const char **charset); +void c_get_string (struct value *value, + gdb::unique_xmalloc_ptr *buffer, + int *length, struct type **char_type, + const char **charset); /* The default implementation of la_symbol_name_matcher. Matches with strncmp_iw. */ extern bool default_symbol_name_matcher (const char *symbol_search_name, const lookup_name_info &lookup_name, - completion_match *match); + completion_match_result *comp_match_res); /* Get LANG's symbol_name_matcher method for LOOKUP_NAME. Returns - default_symbol_name_matcher if not set. */ -symbol_name_matcher_ftype *language_get_symbol_name_matcher + default_symbol_name_matcher if not set. LANG is used as a hint; + the function may ignore it depending on the current language and + LOOKUP_NAME. Specifically, if the current language is Ada, this + may return an Ada matcher regardless of LANG. */ +symbol_name_matcher_ftype *get_symbol_name_matcher (const language_defn *lang, const lookup_name_info &lookup_name); -/* The languages supported by GDB. */ - -extern const struct language_defn auto_language_defn; -extern const struct language_defn unknown_language_defn; -extern const struct language_defn minimal_language_defn; - -extern const struct language_defn ada_language_defn; -extern const struct language_defn asm_language_defn; -extern const struct language_defn c_language_defn; -extern const struct language_defn cplus_language_defn; -extern const struct language_defn d_language_defn; -extern const struct language_defn f_language_defn; -extern const struct language_defn go_language_defn; -extern const struct language_defn m2_language_defn; -extern const struct language_defn objc_language_defn; -extern const struct language_defn opencl_language_defn; -extern const struct language_defn pascal_language_defn; -extern const struct language_defn rust_language_defn; - /* Save the current language and restore it upon destruction. */ class scoped_restore_current_language @@ -681,4 +738,44 @@ private: enum language m_lang; }; +/* If language_mode is language_mode_auto, + then switch current language to the language of SYM + and restore current language upon destruction. + + Else do nothing. */ + +class scoped_switch_to_sym_language_if_auto +{ +public: + + explicit scoped_switch_to_sym_language_if_auto (const struct symbol *sym) + { + if (language_mode == language_mode_auto) + { + m_lang = current_language->la_language; + m_switched = true; + set_language (sym->language ()); + } + else + { + m_switched = false; + /* Assign to m_lang to silence a GCC warning. See + https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80635. */ + m_lang = language_unknown; + } + } + + ~scoped_switch_to_sym_language_if_auto () + { + if (m_switched) + set_language (m_lang); + } + + DISABLE_COPY_AND_ASSIGN (scoped_switch_to_sym_language_if_auto); + +private: + bool m_switched; + enum language m_lang; +}; + #endif /* defined (LANGUAGE_H) */