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Re: [rfa] language hooks for lookup_symbol
On Mon, 19 May 2003 11:19:50 -0400, Elena Zannoni <ezannoni@redhat.com> said:
> Yes. I like it.
Great; it's in, in 3 parts, as you suggested. I'm including the patch
for the third part below.
Thanks a bunch for working with me on this lookup_symbol rewrite.
It's amazing how much we've changed it over the last half-year.
David Carlton
carlton@math.stanford.edu
2003-05-19 David Carlton <carlton@bactrian.org>
* language.h (struct language_defn): Add 'la_value_of_this'
and 'la_lookup_symbol_nonlocal' members.
* symtab.h: Declare basic_lookup_symbol_nonlocal,
lookup_symbol_static, lookup_symbol_global,
lookup_symbol_aux_block.
* symtab.c (lookup_symbol_aux): Call language hooks to determine
if we should search fields of this and how to do static/global
lookup.
(lookup_symbol_aux_block): Make extern.
(basic_lookup_symbol_nonlocal): New.
(lookup_symbol_static, lookup_symbol_global): Ditto.
* ada-lang.c (ada_language_defn): Set 'la_value_of_this' and
'la_lookup_symbol_nonlocal' members.
* c-lang.c (c_language_defn, cplus_language_defn)
(asm_language_defn, minimal_language_defn): Ditto.
* jv-lang.c (java_language_defn): Ditto.
* language.c (unknown_language_defn, auto_language_defn)
(local_language_defn): Ditto.
* m2-lang.c (m2_language_defn): Ditto.
* objc-lang.c (objc_language_defn): Ditto.
* scm-lang.c (scm_language_defn): Ditto.
* f-lang.c (f_language_defn): Ditto, and include value.h as well.
* p-lang.c (pascal_language_defn): Ditto for both.
* Makefile.in (f-lang.o): Depend on value_h.
(p-lang.o): Ditto.
Index: Makefile.in
===================================================================
RCS file: /cvs/src/src/gdb/Makefile.in,v
retrieving revision 1.378
diff -u -p -r1.378 Makefile.in
--- Makefile.in 18 May 2003 21:10:10 -0000 1.378
+++ Makefile.in 20 May 2003 01:51:56 -0000
@@ -1703,7 +1703,7 @@ expprint.o: expprint.c $(defs_h) $(symta
$(block_h)
f-lang.o: f-lang.c $(defs_h) $(gdb_string_h) $(symtab_h) $(gdbtypes_h) \
$(expression_h) $(parser_defs_h) $(language_h) $(f_lang_h) \
- $(valprint_h)
+ $(valprint_h) $(value_h)
f-typeprint.o: f-typeprint.c $(defs_h) $(gdb_obstack_h) $(bfd_h) $(symtab_h) \
$(gdbtypes_h) $(expression_h) $(value_h) $(gdbcore_h) $(target_h) \
$(f_lang_h) $(gdb_string_h)
@@ -2022,7 +2022,7 @@ osabi.o: osabi.c $(defs_h) $(gdb_string_
$(gdbcmd_h) $(command_h) $(arch_utils_h)
p-lang.o: p-lang.c $(defs_h) $(gdb_string_h) $(symtab_h) $(gdbtypes_h) \
$(expression_h) $(parser_defs_h) $(language_h) $(p_lang_h) \
- $(valprint_h)
+ $(valprint_h) $(value_h)
p-typeprint.o: p-typeprint.c $(defs_h) $(gdb_obstack_h) $(bfd_h) $(symtab_h) \
$(gdbtypes_h) $(expression_h) $(value_h) $(gdbcore_h) $(target_h) \
$(language_h) $(p_lang_h) $(typeprint_h) $(gdb_string_h)
Index: ada-lang.c
===================================================================
RCS file: /cvs/src/src/gdb/ada-lang.c,v
retrieving revision 1.25
diff -u -p -r1.25 ada-lang.c
--- ada-lang.c 14 May 2003 17:43:15 -0000 1.25
+++ ada-lang.c 20 May 2003 01:52:04 -0000
@@ -8082,6 +8082,8 @@ const struct language_defn ada_language_
ada_val_print, /* Print a value using appropriate syntax */
ada_value_print, /* Print a top-level value */
NULL, /* Language specific skip_trampoline */
+ value_of_this, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
NULL, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
#if 0
Index: c-lang.c
===================================================================
RCS file: /cvs/src/src/gdb/c-lang.c,v
retrieving revision 1.20
diff -u -p -r1.20 c-lang.c
--- c-lang.c 15 May 2003 22:18:42 -0000 1.20
+++ c-lang.c 20 May 2003 01:52:05 -0000
@@ -553,6 +553,8 @@ const struct language_defn c_language_de
c_val_print, /* Print a value using appropriate syntax */
c_value_print, /* Print a top-level value */
NULL, /* Language specific skip_trampoline */
+ NULL, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
NULL, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"0%lo", "0", "o", ""}, /* Octal format info */
@@ -607,6 +609,8 @@ const struct language_defn cplus_languag
c_val_print, /* Print a value using appropriate syntax */
c_value_print, /* Print a top-level value */
NULL, /* Language specific skip_trampoline */
+ value_of_this, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
cplus_demangle, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"0%lo", "0", "o", ""}, /* Octal format info */
@@ -638,6 +642,8 @@ const struct language_defn asm_language_
c_val_print, /* Print a value using appropriate syntax */
c_value_print, /* Print a top-level value */
NULL, /* Language specific skip_trampoline */
+ NULL, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
NULL, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"0%lo", "0", "o", ""}, /* Octal format info */
@@ -674,6 +680,8 @@ const struct language_defn minimal_langu
c_val_print, /* Print a value using appropriate syntax */
c_value_print, /* Print a top-level value */
NULL, /* Language specific skip_trampoline */
+ NULL, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
NULL, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"0%lo", "0", "o", ""}, /* Octal format info */
Index: f-lang.c
===================================================================
RCS file: /cvs/src/src/gdb/f-lang.c,v
retrieving revision 1.14
diff -u -p -r1.14 f-lang.c
--- f-lang.c 15 May 2003 22:18:42 -0000 1.14
+++ f-lang.c 20 May 2003 01:52:06 -0000
@@ -30,6 +30,7 @@
#include "language.h"
#include "f-lang.h"
#include "valprint.h"
+#include "value.h"
/* The built-in types of F77. FIXME: integer*4 is missing, plain
logical is missing (builtin_type_logical is logical*4). */
@@ -472,6 +473,8 @@ const struct language_defn f_language_de
f_val_print, /* Print a value using appropriate syntax */
c_value_print, /* FIXME */
NULL, /* Language specific skip_trampoline */
+ value_of_this, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
NULL, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"0%o", "0", "o", ""}, /* Octal format info */
Index: jv-lang.c
===================================================================
RCS file: /cvs/src/src/gdb/jv-lang.c,v
retrieving revision 1.19
diff -u -p -r1.19 jv-lang.c
--- jv-lang.c 14 May 2003 17:43:18 -0000 1.19
+++ jv-lang.c 20 May 2003 01:52:08 -0000
@@ -1063,6 +1063,8 @@ const struct language_defn java_language
java_val_print, /* Print a value using appropriate syntax */
java_value_print, /* Print a top-level value */
NULL, /* Language specific skip_trampoline */
+ value_of_this, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
java_demangle, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"0%lo", "0", "o", ""}, /* Octal format info */
Index: language.c
===================================================================
RCS file: /cvs/src/src/gdb/language.c,v
retrieving revision 1.34
diff -u -p -r1.34 language.c
--- language.c 14 May 2003 17:43:18 -0000 1.34
+++ language.c 20 May 2003 01:52:08 -0000
@@ -1479,6 +1479,8 @@ const struct language_defn unknown_langu
unk_lang_val_print, /* Print a value using appropriate syntax */
unk_lang_value_print, /* Print a top-level value */
unk_lang_trampoline, /* Language specific skip_trampoline */
+ value_of_this, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
unk_lang_demangle, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"0%lo", "0", "o", ""}, /* Octal format info */
@@ -1511,6 +1513,8 @@ const struct language_defn auto_language
unk_lang_val_print, /* Print a value using appropriate syntax */
unk_lang_value_print, /* Print a top-level value */
unk_lang_trampoline, /* Language specific skip_trampoline */
+ value_of_this, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
unk_lang_demangle, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"0%lo", "0", "o", ""}, /* Octal format info */
@@ -1542,6 +1546,8 @@ const struct language_defn local_languag
unk_lang_val_print, /* Print a value using appropriate syntax */
unk_lang_value_print, /* Print a top-level value */
unk_lang_trampoline, /* Language specific skip_trampoline */
+ value_of_this, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
unk_lang_demangle, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"0%lo", "0", "o", ""}, /* Octal format info */
Index: language.h
===================================================================
RCS file: /cvs/src/src/gdb/language.h,v
retrieving revision 1.19
diff -u -p -r1.19 language.h
--- language.h 12 Apr 2003 17:41:25 -0000 1.19
+++ language.h 20 May 2003 01:52:09 -0000
@@ -211,6 +211,27 @@ struct language_defn
if it isn't a language tramp for this language. */
CORE_ADDR (*skip_trampoline) (CORE_ADDR pc);
+ /* Now come some hooks for lookup_symbol. */
+
+ /* If this is non-NULL, lookup_symbol will do the 'field_of_this'
+ check, using this function to find the value of this. */
+
+ /* FIXME: carlton/2003-05-19: Audit all the language_defn structs
+ to make sure we're setting this appropriately: I'm sure it
+ could be NULL in more languages. */
+
+ struct value *(*la_value_of_this) (int complain);
+
+ /* 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
+ variables. */
+
+ struct symbol *(*la_lookup_symbol_nonlocal) (const char *,
+ const char *,
+ const struct block *,
+ const domain_enum,
+ struct symtab **);
+
/* Return demangled language symbol, or NULL. */
char *(*la_demangle) (const char *mangled, int options);
Index: m2-lang.c
===================================================================
RCS file: /cvs/src/src/gdb/m2-lang.c,v
retrieving revision 1.10
diff -u -p -r1.10 m2-lang.c
--- m2-lang.c 15 May 2003 22:18:42 -0000 1.10
+++ m2-lang.c 20 May 2003 01:52:09 -0000
@@ -426,6 +426,8 @@ const struct language_defn m2_language_d
m2_val_print, /* Print a value using appropriate syntax */
c_value_print, /* Print a top-level value */
NULL, /* Language specific skip_trampoline */
+ value_of_this, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
NULL, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"%loB", "", "o", "B"}, /* Octal format info */
Index: objc-lang.c
===================================================================
RCS file: /cvs/src/src/gdb/objc-lang.c,v
retrieving revision 1.22
diff -u -p -r1.22 objc-lang.c
--- objc-lang.c 15 May 2003 22:18:42 -0000 1.22
+++ objc-lang.c 20 May 2003 01:52:11 -0000
@@ -701,6 +701,8 @@ const struct language_defn objc_language
c_val_print, /* Print a value using appropriate syntax */
c_value_print, /* Print a top-level value */
objc_skip_trampoline, /* Language specific skip_trampoline */
+ value_of_this, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
objc_demangle, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"0%lo", "0", "o", ""}, /* Octal format info */
Index: p-lang.c
===================================================================
RCS file: /cvs/src/src/gdb/p-lang.c,v
retrieving revision 1.12
diff -u -p -r1.12 p-lang.c
--- p-lang.c 15 May 2003 22:18:43 -0000 1.12
+++ p-lang.c 20 May 2003 01:52:12 -0000
@@ -28,6 +28,7 @@
#include "language.h"
#include "p-lang.h"
#include "valprint.h"
+#include "value.h"
#include <ctype.h>
extern void _initialize_pascal_language (void);
@@ -461,6 +462,8 @@ const struct language_defn pascal_langua
pascal_val_print, /* Print a value using appropriate syntax */
pascal_value_print, /* Print a top-level value */
NULL, /* Language specific skip_trampoline */
+ value_of_this, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
NULL, /* Language specific symbol demangler */
{"", "%", "b", ""}, /* Binary format info */
{"0%lo", "0", "o", ""}, /* Octal format info */
Index: scm-lang.c
===================================================================
RCS file: /cvs/src/src/gdb/scm-lang.c,v
retrieving revision 1.17
diff -u -p -r1.17 scm-lang.c
--- scm-lang.c 14 May 2003 17:43:18 -0000 1.17
+++ scm-lang.c 20 May 2003 01:52:12 -0000
@@ -252,6 +252,8 @@ const struct language_defn scm_language_
scm_val_print, /* Print a value using appropriate syntax */
scm_value_print, /* Print a top-level value */
NULL, /* Language specific skip_trampoline */
+ value_of_this, /* value_of_this */
+ basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
NULL, /* Language specific symbol demangler */
{"", "", "", ""}, /* Binary format info */
{"#o%lo", "#o", "o", ""}, /* Octal format info */
Index: symtab.c
===================================================================
RCS file: /cvs/src/src/gdb/symtab.c,v
retrieving revision 1.108
diff -u -p -r1.108 symtab.c
--- symtab.c 20 May 2003 01:26:58 -0000 1.108
+++ symtab.c 20 May 2003 01:52:16 -0000
@@ -96,13 +96,6 @@ struct symbol *lookup_symbol_aux_local (
struct symtab **symtab);
static
-struct symbol *lookup_symbol_aux_block (const char *name,
- const char *linkage_name,
- const struct block *block,
- const domain_enum domain,
- struct symtab **symtab);
-
-static
struct symbol *lookup_symbol_aux_symtabs (int block_index,
const char *name,
const char *linkage_name,
@@ -957,7 +950,6 @@ lookup_symbol_aux (const char *name, con
int *is_a_field_of_this, struct symtab **symtab)
{
struct symbol *sym;
- const struct block *static_block;
/* Search specified block and its superiors. Don't search
STATIC_BLOCK or GLOBAL_BLOCK. */
@@ -967,11 +959,13 @@ lookup_symbol_aux (const char *name, con
if (sym != NULL)
return sym;
- /* C++/Java/Objective-C: If requested to do so by the caller,
- check to see if NAME is a field of `this'. */
- if (is_a_field_of_this)
+ /* If requested to do so by the caller and if appropriate for the
+ current language, check to see if NAME is a field of `this'. */
+
+ if (current_language->la_value_of_this != NULL
+ && is_a_field_of_this != NULL)
{
- struct value *v = value_of_this (0);
+ struct value *v = current_language->la_value_of_this (0);
*is_a_field_of_this = 0;
if (v && check_field (v, name))
@@ -983,51 +977,12 @@ lookup_symbol_aux (const char *name, con
}
}
- /* If there's a static block to search, search it next. */
-
- /* NOTE: carlton/2002-12-05: There is a question as to whether or
- not it would be appropriate to search the current global block
- here as well. (That's what this code used to do before the
- is_a_field_of_this check was moved up.) On the one hand, it's
- redundant with the lookup_symbol_aux_symtabs search that happens
- next. On the other hand, if decode_line_1 is passed an argument
- like filename:var, then the user presumably wants 'var' to be
- searched for in filename. On the third hand, there shouldn't be
- multiple global variables all of which are named 'var', and it's
- not like decode_line_1 has ever restricted its search to only
- global variables in a single filename. All in all, only
- searching the static block here seems best: it's correct and it's
- cleanest. */
-
- /* NOTE: carlton/2002-12-05: There's also a possible performance
- issue here: if you usually search for global symbols in the
- current file, then it would be slightly better to search the
- current global block before searching all the symtabs. But there
- are other factors that have a much greater effect on performance
- than that one, so I don't think we should worry about that for
- now. */
-
- static_block = block_static_block (block);
- if (static_block != NULL)
- {
- sym = lookup_symbol_aux_block (name, linkage_name, static_block,
- domain, symtab);
- if (sym != NULL)
- return sym;
- }
-
- /* Now search all global blocks. Do the symtab's first, then
- check the psymtab's. If a psymtab indicates the existence
- of the desired name as a global, then do psymtab-to-symtab
- conversion on the fly and return the found symbol. */
+ /* Now do whatever is appropriate for the current language to look
+ up static and global variables. */
- sym = lookup_symbol_aux_symtabs (GLOBAL_BLOCK, name, linkage_name,
- domain, symtab);
- if (sym != NULL)
- return sym;
-
- sym = lookup_symbol_aux_psymtabs (GLOBAL_BLOCK, name, linkage_name,
- domain, symtab);
+ sym = current_language->la_lookup_symbol_nonlocal (name, linkage_name,
+ block, domain,
+ symtab);
if (sym != NULL)
return sym;
@@ -1086,7 +1041,7 @@ lookup_symbol_aux_local (const char *nam
/* Look up a symbol in a block; if found, locate its symtab, fixup the
symbol, and set block_found appropriately. */
-static struct symbol *
+struct symbol *
lookup_symbol_aux_block (const char *name, const char *linkage_name,
const struct block *block,
const domain_enum domain,
@@ -1343,6 +1298,93 @@ lookup_symbol_aux_minsyms (const char *n
return NULL;
}
#endif /* 0 */
+
+/* A default version of lookup_symbol_nonlocal for use by languages
+ that can't think of anything better to do. This implements the C
+ lookup rules. */
+
+struct symbol *
+basic_lookup_symbol_nonlocal (const char *name,
+ const char *linkage_name,
+ const struct block *block,
+ const domain_enum domain,
+ struct symtab **symtab)
+{
+ struct symbol *sym;
+
+ /* NOTE: carlton/2003-05-19: The comments below were written when
+ this (or what turned into this) was part of lookup_symbol_aux;
+ I'm much less worried about these questions now, since these
+ decisions have turned out well, but I leave these comments here
+ for posterity. */
+
+ /* NOTE: carlton/2002-12-05: There is a question as to whether or
+ not it would be appropriate to search the current global block
+ here as well. (That's what this code used to do before the
+ is_a_field_of_this check was moved up.) On the one hand, it's
+ redundant with the lookup_symbol_aux_symtabs search that happens
+ next. On the other hand, if decode_line_1 is passed an argument
+ like filename:var, then the user presumably wants 'var' to be
+ searched for in filename. On the third hand, there shouldn't be
+ multiple global variables all of which are named 'var', and it's
+ not like decode_line_1 has ever restricted its search to only
+ global variables in a single filename. All in all, only
+ searching the static block here seems best: it's correct and it's
+ cleanest. */
+
+ /* NOTE: carlton/2002-12-05: There's also a possible performance
+ issue here: if you usually search for global symbols in the
+ current file, then it would be slightly better to search the
+ current global block before searching all the symtabs. But there
+ are other factors that have a much greater effect on performance
+ than that one, so I don't think we should worry about that for
+ now. */
+
+ sym = lookup_symbol_static (name, linkage_name, block, domain, symtab);
+ if (sym != NULL)
+ return sym;
+
+ return lookup_symbol_global (name, linkage_name, domain, symtab);
+}
+
+/* Lookup a symbol in the static block associated to BLOCK, if there
+ is one; do nothing if BLOCK is NULL or a global block. */
+
+struct symbol *
+lookup_symbol_static (const char *name,
+ const char *linkage_name,
+ const struct block *block,
+ const domain_enum domain,
+ struct symtab **symtab)
+{
+ const struct block *static_block = block_static_block (block);
+
+ if (static_block != NULL)
+ return lookup_symbol_aux_block (name, linkage_name, static_block,
+ domain, symtab);
+ else
+ return NULL;
+}
+
+/* Lookup a symbol in all files' global blocks (searching psymtabs if
+ necessary). */
+
+struct symbol *
+lookup_symbol_global (const char *name,
+ const char *linkage_name,
+ const domain_enum domain,
+ struct symtab **symtab)
+{
+ struct symbol *sym;
+
+ sym = lookup_symbol_aux_symtabs (GLOBAL_BLOCK, name, linkage_name,
+ domain, symtab);
+ if (sym != NULL)
+ return sym;
+
+ return lookup_symbol_aux_psymtabs (GLOBAL_BLOCK, name, linkage_name,
+ domain, symtab);
+}
/* Look, in partial_symtab PST, for symbol whose natural name is NAME.
If LINKAGE_NAME is non-NULL, check in addition that the symbol's
Index: symtab.h
===================================================================
RCS file: /cvs/src/src/gdb/symtab.h,v
retrieving revision 1.71
diff -u -p -r1.71 symtab.h
--- symtab.h 15 May 2003 22:23:24 -0000 1.71
+++ symtab.h 20 May 2003 01:52:18 -0000
@@ -988,6 +988,45 @@ extern struct symbol *lookup_symbol (con
const domain_enum, int *,
struct symtab **);
+/* A default version of lookup_symbol_nonlocal for use by languages
+ that can't think of anything better to do. */
+
+extern struct symbol *basic_lookup_symbol_nonlocal (const char *,
+ const char *,
+ const struct block *,
+ const domain_enum,
+ struct symtab **);
+
+/* Some helper functions for languages that need to write their own
+ lookup_symbol_nonlocal functions. */
+
+/* Lookup a symbol in the static block associated to BLOCK, if there
+ is one; do nothing if BLOCK is NULL or a global block. */
+
+extern struct symbol *lookup_symbol_static (const char *name,
+ const char *linkage_name,
+ const struct block *block,
+ const domain_enum domain,
+ struct symtab **symtab);
+
+/* Lookup a symbol in all files' global blocks (searching psymtabs if
+ necessary). */
+
+extern struct symbol *lookup_symbol_global (const char *name,
+ const char *linkage_name,
+ const domain_enum domain,
+ struct symtab **symtab);
+
+/* Lookup a symbol within the block BLOCK. This, unlike
+ lookup_symbol_block, will set SYMTAB and BLOCK_FOUND correctly, and
+ will fix up the symbol if necessary. */
+
+extern struct symbol *lookup_symbol_aux_block (const char *name,
+ const char *linkage_name,
+ const struct block *block,
+ const domain_enum domain,
+ struct symtab **symtab);
+
/* lookup a symbol by name, within a specified block */
extern struct symbol *lookup_block_symbol (const struct block *, const char *,