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author | Iain Buclaw <ibuclaw@gdcproject.org> | 2015-08-13 20:34:15 +0200 |
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committer | Iain Buclaw <ibuclaw@gdcproject.org> | 2015-08-13 21:07:09 +0200 |
commit | bc7c9fab612d4d33f7fe5d17eef4f5bd5cdc4144 (patch) | |
tree | 7b016c69aeb9253d52045f9fa374a063f125d911 /gdb/d-namespace.c | |
parent | 52bbc560524ec3691203eccd05207d13913a1e35 (diff) | |
download | fsf-binutils-gdb-bc7c9fab612d4d33f7fe5d17eef4f5bd5cdc4144.zip fsf-binutils-gdb-bc7c9fab612d4d33f7fe5d17eef4f5bd5cdc4144.tar.gz fsf-binutils-gdb-bc7c9fab612d4d33f7fe5d17eef4f5bd5cdc4144.tar.bz2 |
[D] Support looking up symbols in the current and imported modules.
In D, there is the notion of modules, and importing from one to the other,
whether it is a basic, selective or renamed import declaration.
module A;
import X;
void foo() {
import Y : bar;
}
If the compiler emits DW_TAG_imported_declaration at the appropriate locations,
then we can make use of what gdb stores in using_direct when performing
nonlocal symbol lookups.
gdb/ChangeLog
* Makefile.in (SFILES): Add d-namespace.c.
(COMMON_OBS): Add d-namespace.o.
* d-lang.c (d_language_defn): Use d_lookup_symbol_nonlocal as the
la_lookup_symbol_nonlocal callback function pointer.
* d-lang.h (d_lookup_symbol_nonlocal): New declaration.
(d_lookup_nested_symbol): New declaration.
* d-namespace.c: New file.
Diffstat (limited to 'gdb/d-namespace.c')
-rw-r--r-- | gdb/d-namespace.c | 562 |
1 files changed, 562 insertions, 0 deletions
diff --git a/gdb/d-namespace.c b/gdb/d-namespace.c new file mode 100644 index 0000000..9a558d1 --- /dev/null +++ b/gdb/d-namespace.c @@ -0,0 +1,562 @@ +/* Helper routines for D support in GDB. + + Copyright (C) 2014-2015 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "defs.h" +#include "symtab.h" +#include "block.h" +#include "language.h" +#include "namespace.h" +#include "d-lang.h" +#include "gdb_obstack.h" + +/* This returns the length of first component of NAME, which should be + the demangled name of a D variable/function/method/etc. + Specifically, it returns the index of the first dot forming the + boundary of the first component: so, given 'A.foo' or 'A.B.foo' + it returns the 1, and given 'foo', it returns 0. */ + +/* The character in NAME indexed by the return value is guaranteed to + always be either '.' or '\0'. */ + +static unsigned int +d_find_first_component (const char *name) +{ + unsigned int index = 0; + + for (;; ++index) + { + if (name[index] == '.' || name[index] == '\0') + return index; + } +} + +/* If NAME is the fully-qualified name of a D function/variable/method, + this returns the length of its entire prefix: all of the modules and + classes that make up its name. Given 'A.foo', it returns 1, given + 'A.B.foo', it returns 4, given 'foo', it returns 0. */ + +static unsigned int +d_entire_prefix_len (const char *name) +{ + unsigned int current_len = d_find_first_component (name); + unsigned int previous_len = 0; + + while (name[current_len] != '\0') + { + gdb_assert (name[current_len] == '.'); + previous_len = current_len; + /* Skip the '.' */ + current_len++; + current_len += d_find_first_component (name + current_len); + } + + return previous_len; +} + +/* Look up NAME in BLOCK's static block and in global blocks. + If SEARCH is non-zero, search through base classes for a matching + symbol. Other arguments are as in d_lookup_symbol_nonlocal. */ + +static struct block_symbol +d_lookup_symbol (const char *name, const struct block *block, + const domain_enum domain, int search) +{ + struct block_symbol sym; + + sym = lookup_symbol_in_static_block (name, block, domain); + if (sym.symbol != NULL) + return sym; + + sym = lookup_global_symbol (name, block, domain); + + if (sym.symbol != NULL) + return sym; + + if (search) + { + char *classname, *nested; + unsigned int prefix_len; + struct cleanup *cleanup; + struct block_symbol class_sym; + + /* A simple lookup failed. Check if the symbol was defined in + a base class. */ + + cleanup = make_cleanup (null_cleanup, NULL); + + /* Find the name of the class and the name of the method, + variable, etc. */ + prefix_len = d_entire_prefix_len (name); + + /* If no prefix was found, search "this". */ + if (prefix_len == 0) + { + struct type *type; + struct block_symbol lang_this; + + lang_this = lookup_language_this (language_def (language_d), block); + if (lang_this.symbol == NULL) + { + do_cleanups (cleanup); + return (struct block_symbol) {NULL, NULL}; + } + + type = check_typedef (TYPE_TARGET_TYPE (SYMBOL_TYPE (lang_this.symbol))); + classname = xstrdup (TYPE_NAME (type)); + nested = xstrdup (name); + } + else + { + /* The class name is everything up to and including PREFIX_LEN. */ + classname = savestring (name, prefix_len); + + /* The rest of the name is everything else past the initial scope + operator. */ + nested = xstrdup (name + prefix_len + 1); + } + + /* Add cleanups to free memory for these strings. */ + make_cleanup (xfree, classname); + make_cleanup (xfree, nested); + + /* Lookup a class named CLASSNAME. If none is found, there is nothing + more that can be done. */ + class_sym = lookup_global_symbol (classname, block, domain); + if (class_sym.symbol == NULL) + { + do_cleanups (cleanup); + return (struct block_symbol) {NULL, NULL}; + } + + /* Look for a symbol named NESTED in this class. */ + sym = d_lookup_nested_symbol (SYMBOL_TYPE (class_sym.symbol), + nested, block); + do_cleanups (cleanup); + } + + return sym; +} + +/* Look up NAME in the D module MODULE. Other arguments are as in + d_lookup_symbol_nonlocal. If SEARCH is non-zero, search through + base classes for a matching symbol. */ + +static struct block_symbol +d_lookup_symbol_in_module (const char *module, const char *name, + const struct block *block, + const domain_enum domain, int search) +{ + char *concatenated_name = NULL; + + if (module[0] != '\0') + { + concatenated_name = alloca (strlen (module) + + strlen (name) + 2); + strcpy (concatenated_name, module); + strcat (concatenated_name, "."); + strcat (concatenated_name, name); + name = concatenated_name; + } + + return d_lookup_symbol (name, block, domain, search); +} + +/* Lookup NAME at module scope. SCOPE is the module that the current + function is defined within; only consider modules whose length is at + least SCOPE_LEN. Other arguments are as in d_lookup_symbol_nonlocal. + + For example, if we're within a function A.B.f and looking for a + symbol x, this will get called with NAME = "x", SCOPE = "A.B", and + SCOPE_LEN = 0. It then calls itself with NAME and SCOPE the same, + but with SCOPE_LEN = 1. And then it calls itself with NAME and + SCOPE the same, but with SCOPE_LEN = 4. This third call looks for + "A.B.x"; if it doesn't find it, then the second call looks for "A.x", + and if that call fails, then the first call looks for "x". */ + +static struct block_symbol +lookup_module_scope (const char *name, const struct block *block, + const domain_enum domain, const char *scope, + int scope_len) +{ + char *module; + + if (scope[scope_len] != '\0') + { + /* Recursively search for names in child modules first. */ + + struct block_symbol sym; + int new_scope_len = scope_len; + + /* If the current scope is followed by ".", skip past that. */ + if (new_scope_len != 0) + { + gdb_assert (scope[new_scope_len] == '.'); + new_scope_len++; + } + new_scope_len += d_find_first_component (scope + new_scope_len); + sym = lookup_module_scope (name, block, domain, + scope, new_scope_len); + if (sym.symbol != NULL) + return sym; + } + + /* Okay, we didn't find a match in our children, so look for the + name in the current module. */ + + module = alloca (scope_len + 1); + strncpy (module, scope, scope_len); + module[scope_len] = '\0'; + return d_lookup_symbol_in_module (module, name, + block, domain, 1); +} + +/* Search through the base classes of PARENT_TYPE for a symbol named + NAME in block BLOCK. */ + +static struct block_symbol +find_symbol_in_baseclass (struct type *parent_type, const char *name, + const struct block *block) +{ + char *concatenated_name = NULL; + struct block_symbol sym; + struct cleanup *cleanup; + int i; + + sym.symbol = NULL; + sym.block = NULL; + cleanup = make_cleanup (free_current_contents, &concatenated_name); + + for (i = 0; i < TYPE_N_BASECLASSES (parent_type); ++i) + { + size_t len; + struct type *base_type = TYPE_BASECLASS (parent_type, i); + const char *base_name = TYPE_BASECLASS_NAME (parent_type, i); + + if (base_name == NULL) + continue; + + /* Search this particular base class. */ + sym = d_lookup_symbol_in_module (base_name, name, block, + VAR_DOMAIN, 0); + if (sym.symbol != NULL) + break; + + /* Now search all static file-level symbols. We have to do this for + things like typedefs in the class. First search in this symtab, + what we want is possibly there. */ + len = strlen (base_name) + strlen (name) + 2; + concatenated_name = xrealloc (concatenated_name, len); + xsnprintf (concatenated_name, len, "%s.%s", base_name, name); + sym = lookup_symbol_in_static_block (concatenated_name, block, + VAR_DOMAIN); + if (sym.symbol != NULL) + break; + + /* Nope. We now have to search all static blocks in all objfiles, + even if block != NULL, because there's no guarantees as to which + symtab the symbol we want is in. */ + sym = lookup_static_symbol (concatenated_name, VAR_DOMAIN); + if (sym.symbol != NULL) + break; + + /* If this class has base classes, search them next. */ + base_type = check_typedef (base_type); + if (TYPE_N_BASECLASSES (base_type) > 0) + { + sym = find_symbol_in_baseclass (base_type, name, block); + if (sym.symbol != NULL) + break; + } + } + + do_cleanups (cleanup); + return sym; +} + +/* Look up a symbol named NESTED_NAME that is nested inside the D + class or module given by PARENT_TYPE, from within the context + given by BLOCK. Return NULL if there is no such nested type. */ + +struct block_symbol +d_lookup_nested_symbol (struct type *parent_type, + const char *nested_name, + const struct block *block) +{ + /* type_name_no_tag_required provides better error reporting using the + original type. */ + struct type *saved_parent_type = parent_type; + + parent_type = check_typedef (parent_type); + + switch (TYPE_CODE (parent_type)) + { + case TYPE_CODE_STRUCT: + case TYPE_CODE_UNION: + case TYPE_CODE_MODULE: + { + int size; + const char *parent_name = type_name_no_tag_or_error (saved_parent_type); + struct block_symbol sym + = d_lookup_symbol_in_module (parent_name, nested_name, + block, VAR_DOMAIN, 0); + char *concatenated_name; + + if (sym.symbol != NULL) + return sym; + + /* Now search all static file-level symbols. We have to do this + for things like typedefs in the class. We do not try to + guess any imported module as even the fully specified + module search is already not D compliant and more assumptions + could make it too magic. */ + size = strlen (parent_name) + strlen (nested_name) + 2; + concatenated_name = alloca (size); + + xsnprintf (concatenated_name, size, "%s.%s", + parent_name, nested_name); + + sym = lookup_static_symbol (concatenated_name, VAR_DOMAIN); + if (sym.symbol != NULL) + return sym; + + /* If no matching symbols were found, try searching any + base classes. */ + return find_symbol_in_baseclass (parent_type, nested_name, block); + } + + case TYPE_CODE_FUNC: + case TYPE_CODE_METHOD: + return (struct block_symbol) {NULL, NULL}; + + default: + gdb_assert_not_reached ("called with non-aggregate type."); + } +} + +/* Used for cleanups to reset the "searched" flag incase + of an error. */ + +static void +reset_directive_searched (void *data) +{ + struct using_direct *direct = data; + direct->searched = 0; +} + +/* Search for NAME by applying all import statements belonging to + BLOCK which are applicable in SCOPE. + + If SEARCH_PARENTS the search will include imports which are + applicable in parents of SCOPE. + Example: + + module A; + import X; + void B() { + import Y; + } + + If SCOPE is "A.B" and SEARCH_PARENTS is true, the imports of + modules X and Y will be considered. If SEARCH_PARENTS is false + only the import of Y is considered. */ + +static struct block_symbol +d_lookup_symbol_imports (const char *scope, const char *name, + const struct block *block, + const domain_enum domain, + const int search_parents) +{ + struct using_direct *current; + struct block_symbol sym; + int directive_match; + struct cleanup *searched_cleanup; + + /* First, try to find the symbol in the given module. */ + sym = d_lookup_symbol_in_module (scope, name, block, domain, 1); + + if (sym.symbol != NULL) + return sym; + + /* Go through the using directives. If any of them add new names to + the module we're searching in, see if we can find a match by + applying them. */ + + for (current = block_using (block); + current != NULL; + current = current->next) + { + const char **excludep; + int len = strlen (current->import_dest); + + directive_match = (search_parents + ? (strncmp (scope, current->import_dest, len) == 0 + && (len == 0 + || scope[len] == '.' + || scope[len] == '\0')) + : strcmp (scope, current->import_dest) == 0); + + /* If the import destination is the current scope or one of its + ancestors then it is applicable. */ + if (directive_match && !current->searched) + { + /* Mark this import as searched so that the recursive call + does not search it again. */ + current->searched = 1; + searched_cleanup = make_cleanup (reset_directive_searched, + current); + + /* If there is an import of a single declaration, compare the + imported declaration (after optional renaming by its alias) + with the sought out name. If there is a match pass + current->import_src as MODULE to direct the search towards + the imported module. */ + if (current->declaration + && strcmp (name, current->alias + ? current->alias : current->declaration) == 0) + sym = d_lookup_symbol_in_module (current->import_src, + current->declaration, + block, domain, 1); + + /* If a symbol was found or this import statement was an import + declaration, the search of this import is complete. */ + if (sym.symbol != NULL || current->declaration) + { + current->searched = 0; + discard_cleanups (searched_cleanup); + + if (sym.symbol != NULL) + return sym; + + continue; + } + + /* Do not follow CURRENT if NAME matches its EXCLUDES. */ + for (excludep = current->excludes; *excludep; excludep++) + if (strcmp (name, *excludep) == 0) + break; + if (*excludep) + { + discard_cleanups (searched_cleanup); + continue; + } + + /* If the import statement is creating an alias. */ + if (current->alias != NULL) + { + if (strcmp (name, current->alias) == 0) + { + /* If the alias matches the sought name. Pass + current->import_src as the NAME to direct the + search towards the aliased module. */ + sym = lookup_module_scope (current->import_src, block, + domain, scope, 0); + } + else + { + /* If the alias matches the first component of the + sought name, pass current->import_src as MODULE + to direct the search, skipping over the aliased + component in NAME. */ + int name_scope = d_find_first_component (name); + + if (name[name_scope] != '\0' + && strncmp (name, current->alias, name_scope) == 0) + { + /* Skip the '.' */ + name_scope++; + sym = d_lookup_symbol_imports (current->import_src, + name + name_scope, + block, domain, 0); + } + } + } + else + { + /* If this import statement creates no alias, pass + current->import_src as MODULE to direct the search + towards the imported module. */ + sym = d_lookup_symbol_imports (current->import_src, + name, block, domain, 0); + } + current->searched = 0; + discard_cleanups (searched_cleanup); + + if (sym.symbol != NULL) + return sym; + } + } + + return (struct block_symbol) {NULL, NULL}; +} + +/* Searches for NAME in the current module, and by applying relevant + import statements belonging to BLOCK and its parents. SCOPE is the + module scope of the context in which the search is being evaluated. */ + +static struct block_symbol +d_lookup_symbol_module (const char *scope, const char *name, + const struct block *block, + const domain_enum domain) +{ + struct block_symbol sym; + + /* First, try to find the symbol in the given module. */ + sym = d_lookup_symbol_in_module (scope, name, + block, domain, 1); + if (sym.symbol != NULL) + return sym; + + /* Search for name in modules imported to this and parent + blocks. */ + while (block != NULL) + { + sym = d_lookup_symbol_imports (scope, name, block, domain, 1); + + if (sym.symbol != NULL) + return sym; + + block = BLOCK_SUPERBLOCK (block); + } + + return (struct block_symbol) {NULL, NULL}; +} + +/* The D-specific version of name lookup for static and global names + This makes sure that names get looked for in all modules that are + in scope. NAME is the natural name of the symbol that we're looking + looking for, BLOCK is the block that we're searching within, DOMAIN + says what kind of symbols we're looking for, and if SYMTAB is non-NULL, + we should store the symtab where we found the symbol in it. */ + +struct block_symbol +d_lookup_symbol_nonlocal (const struct language_defn *langdef, + const char *name, + const struct block *block, + const domain_enum domain) +{ + struct block_symbol sym; + const char *scope = block_scope (block); + + sym = lookup_module_scope (name, block, domain, scope, 0); + if (sym.symbol != NULL) + return sym; + + return d_lookup_symbol_module (scope, name, block, domain); +} + |