/* GDB routines for manipulating the minimal symbol tables.
- Copyright 1992 Free Software Foundation, Inc.
+ Copyright 1992, 1993, 1994 Free Software Foundation, Inc.
Contributed by Cygnus Support, using pieces from other GDB modules.
This file is part of GDB.
#include "defs.h"
+#include <string.h>
#include "symtab.h"
#include "bfd.h"
#include "symfile.h"
#include "objfiles.h"
#include "demangle.h"
+#include "gdb-stabs.h"
/* Accumulate the minimal symbols for each objfile in bunches of BUNCH_SIZE.
At the end, copy them all into one newly allocated location on an objfile's
struct objfile *objfile;
struct minimal_symbol *msymbol;
struct minimal_symbol *found_symbol = NULL;
-#ifdef IBM6000_TARGET
+ struct minimal_symbol *found_file_symbol = NULL;
struct minimal_symbol *trampoline_symbol = NULL;
-#endif
for (objfile = object_files;
objfile != NULL && found_symbol == NULL;
{
if (SYMBOL_MATCHES_NAME (msymbol, name))
{
-#ifdef IBM6000_TARGET
- /* I *think* all platforms using shared libraries (and
- trampoline code) will suffer this problem. Consider a
- case where there are 5 shared libraries, each referencing
- `foo' with a trampoline entry. When someone wants to put
- a breakpoint on `foo' and the only info we have is minimal
- symbol vector, we want to use the real `foo', rather than
- one of those trampoline entries. MGO */
- /* If a trampoline symbol is found, we prefer to keep looking
- for the *real* symbol. If the actual symbol not found,
- then we'll use the trampoline entry. Sorry for the machine
- dependent code here, but I hope this will benefit other
- platforms as well. For trampoline entries, we used
- mst_unknown earlier. Perhaps we should define a
- `mst_trampoline' type?? */
-
- if (MSYMBOL_TYPE (msymbol) != mst_unknown)
- found_symbol = msymbol;
- else if (MSYMBOL_TYPE (msymbol) == mst_unknown &&
- !trampoline_symbol)
- trampoline_symbol = msymbol;
-
-#else
- found_symbol = msymbol;
-#endif
+ switch (MSYMBOL_TYPE (msymbol))
+ {
+ case mst_file_text:
+ case mst_file_data:
+ case mst_file_bss:
+ /* It is file-local. If we find more than one, just
+ return the latest one (the user can't expect
+ useful behavior in that case). */
+ found_file_symbol = msymbol;
+ break;
+
+ case mst_solib_trampoline:
+
+ /* If a trampoline symbol is found, we prefer to
+ keep looking for the *real* symbol. If the
+ actual symbol is not found, then we'll use the
+ trampoline entry. */
+ if (trampoline_symbol == NULL)
+ trampoline_symbol = msymbol;
+ break;
+
+ case mst_unknown:
+ default:
+ found_symbol = msymbol;
+ break;
+ }
}
}
}
}
-#ifdef IBM6000_TARGET
- return found_symbol ? found_symbol : trampoline_symbol;
-#endif
+ /* External symbols are best. */
+ if (found_symbol)
+ return found_symbol;
+
+ /* File-local symbols are next best. */
+ if (found_file_symbol)
+ return found_file_symbol;
+
+ /* Symbols for shared library trampolines are next best. */
+ if (trampoline_symbol)
+ return trampoline_symbol;
- return (found_symbol);
+ return NULL;
}
equal to PC. Returns a pointer to the minimal symbol if such a symbol
is found, or NULL if PC is not in a suitable range. Note that we need
to look through ALL the minimal symbol tables before deciding on the
- symbol that comes closest to the specified PC. */
+ symbol that comes closest to the specified PC. This is because objfiles
+ can overlap, for example objfile A has .text at 0x100 and .data at 0x40000
+ and objfile B has .text at 0x234 and .data at 0x40048. */
struct minimal_symbol *
lookup_minimal_symbol_by_pc (pc)
{
lo = 0;
hi = objfile -> minimal_symbol_count - 1;
-
+
/* This code assumes that the minimal symbols are sorted by
ascending address values. If the pc value is greater than or
equal to the first symbol's address, then some symbol in this
objfile's minimal symbol table. See if it is the best one
overall. */
- if ((best_symbol == NULL) ||
- (SYMBOL_VALUE_ADDRESS (best_symbol) <
- SYMBOL_VALUE_ADDRESS (&msymbol[hi])))
+ /* Skip any absolute symbols. This is apparently what adb
+ and dbx do, and is needed for the CM-5. There are two
+ known possible problems: (1) on ELF, apparently end, edata,
+ etc. are absolute. Not sure ignoring them here is a big
+ deal, but if we want to use them, the fix would go in
+ elfread.c. (2) I think shared library entry points on the
+ NeXT are absolute. If we want special handling for this
+ it probably should be triggered by a special
+ mst_abs_or_lib or some such. */
+ while (hi >= 0
+ && msymbol[hi].type == mst_abs)
+ --hi;
+
+ if (hi >= 0
+ && ((best_symbol == NULL) ||
+ (SYMBOL_VALUE_ADDRESS (best_symbol) <
+ SYMBOL_VALUE_ADDRESS (&msymbol[hi]))))
{
best_symbol = &msymbol[hi];
}
}
- }
+ }
}
return (best_symbol);
}
}
void
-prim_record_minimal_symbol (name, address, ms_type)
+prim_record_minimal_symbol (name, address, ms_type, objfile)
const char *name;
CORE_ADDR address;
enum minimal_symbol_type ms_type;
+ struct objfile *objfile;
{
- register struct msym_bunch *new;
- register struct minimal_symbol *msymbol;
+ int section;
- if (msym_bunch_index == BUNCH_SIZE)
+ switch (ms_type)
{
- new = (struct msym_bunch *) xmalloc (sizeof (struct msym_bunch));
- msym_bunch_index = 0;
- new -> next = msym_bunch;
- msym_bunch = new;
+ case mst_text:
+ case mst_file_text:
+ case mst_solib_trampoline:
+ section = SECT_OFF_TEXT;
+ break;
+ case mst_data:
+ case mst_file_data:
+ section = SECT_OFF_DATA;
+ break;
+ case mst_bss:
+ case mst_file_bss:
+ section = SECT_OFF_BSS;
+ break;
+ default:
+ section = -1;
}
- msymbol = &msym_bunch -> contents[msym_bunch_index];
- SYMBOL_NAME (msymbol) = (char *) name;
- /* Note that SYMBOL_LANGUAGE and SYMBOL_DEMANGLED_NAME are not initialized
- to their final values until the minimal symbols are actually added to
- the minimal symbol table. We just set them to a known state here so
- random values won't confuse anyone debugging the debugger. */
- SYMBOL_LANGUAGE (msymbol) = language_unknown;
- SYMBOL_DEMANGLED_NAME (msymbol) = NULL;
- SYMBOL_VALUE_ADDRESS (msymbol) = address;
- MSYMBOL_TYPE (msymbol) = ms_type;
- /* FIXME: This info, if it remains, needs its own field. */
- MSYMBOL_INFO (msymbol) = NULL; /* FIXME! */
- msym_bunch_index++;
- msym_count++;
-}
-/* FIXME: Why don't we just combine this function with the one above
- and pass it a NULL info pointer value if info is not needed? */
+ prim_record_minimal_symbol_and_info (name, address, ms_type,
+ NULL, section, objfile);
+}
void
-prim_record_minimal_symbol_and_info (name, address, ms_type, info)
+prim_record_minimal_symbol_and_info (name, address, ms_type, info, section,
+ objfile)
const char *name;
CORE_ADDR address;
enum minimal_symbol_type ms_type;
char *info;
+ int section;
+ struct objfile *objfile;
{
register struct msym_bunch *new;
register struct minimal_symbol *msymbol;
+ if (ms_type == mst_file_text)
+ {
+ /* Don't put gcc_compiled, __gnu_compiled_cplus, and friends into
+ the minimal symbols, because if there is also another symbol
+ at the same address (e.g. the first function of the file),
+ lookup_minimal_symbol_by_pc would have no way of getting the
+ right one. */
+ if (name[0] == 'g'
+ && (strcmp (name, GCC_COMPILED_FLAG_SYMBOL) == 0
+ || strcmp (name, GCC2_COMPILED_FLAG_SYMBOL) == 0))
+ return;
+
+ {
+ const char *tempstring = name;
+ if (tempstring[0] == bfd_get_symbol_leading_char (objfile->obfd))
+ ++tempstring;
+ if (STREQN (tempstring, "__gnu_compiled", 14))
+ return;
+ }
+ }
+
if (msym_bunch_index == BUNCH_SIZE)
{
new = (struct msym_bunch *) xmalloc (sizeof (struct msym_bunch));
}
msymbol = &msym_bunch -> contents[msym_bunch_index];
SYMBOL_NAME (msymbol) = (char *) name;
- /* Note that SYMBOL_LANGUAGE and SYMBOL_DEMANGLED_NAME are not initialized
- to their final values until the minimal symbols are actually added to
- the minimal symbol table. We just set them to a known state here so
- random values won't confuse anyone debugging the debugger. */
- SYMBOL_LANGUAGE (msymbol) = language_unknown;
- SYMBOL_DEMANGLED_NAME (msymbol) = NULL;
+ SYMBOL_INIT_LANGUAGE_SPECIFIC (msymbol, language_unknown);
SYMBOL_VALUE_ADDRESS (msymbol) = address;
+ SYMBOL_SECTION (msymbol) = section;
+
MSYMBOL_TYPE (msymbol) = ms_type;
/* FIXME: This info, if it remains, needs its own field. */
MSYMBOL_INFO (msymbol) = info; /* FIXME! */
register struct minimal_symbol *msymbols;
int alloc_count;
register char leading_char;
- char *demangled_name;
if (msym_count > 0)
{
SYMBOL_VALUE_ADDRESS (&msymbols[mcount]) = 0;
MSYMBOL_INFO (&msymbols[mcount]) = NULL;
MSYMBOL_TYPE (&msymbols[mcount]) = mst_unknown;
- SYMBOL_LANGUAGE (&msymbols[mcount]) = language_unknown;
- SYMBOL_DEMANGLED_NAME (&msymbols[mcount]) = NULL;
+ SYMBOL_INIT_LANGUAGE_SPECIFIC (&msymbols[mcount], language_unknown);
/* Attach the minimal symbol table to the specified objfile.
The strings themselves are also located in the symbol_obstack
for ( ; mcount-- > 0 ; msymbols++)
{
- if (SYMBOL_LANGUAGE (msymbols) == language_auto)
- {
- demangled_name = cplus_demangle (SYMBOL_NAME (msymbols),
- DMGL_PARAMS | DMGL_ANSI);
- if (demangled_name == NULL)
- {
- SYMBOL_LANGUAGE (msymbols) = language_unknown;
- }
- else
- {
- SYMBOL_LANGUAGE (msymbols) = language_cplus;
- SYMBOL_DEMANGLED_NAME (msymbols) =
- obsavestring (demangled_name, strlen (demangled_name),
- &objfile->symbol_obstack);
-
- free (demangled_name);
- }
- }
+ SYMBOL_INIT_DEMANGLED_NAME (msymbols, &objfile->symbol_obstack);
+ }
+ }
+}
+
+/* Sort all the minimal symbols in OBJFILE. */
+
+void
+msymbols_sort (objfile)
+ struct objfile *objfile;
+{
+ qsort (objfile->msymbols, objfile->minimal_symbol_count,
+ sizeof (struct minimal_symbol), compare_minimal_symbols);
+}
+
+/* Check if PC is in a shared library trampoline code stub.
+ Return minimal symbol for the trampoline entry or NULL if PC is not
+ in a trampoline code stub. */
+
+struct minimal_symbol *
+lookup_solib_trampoline_symbol_by_pc (pc)
+ CORE_ADDR pc;
+{
+ struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (pc);
+
+ if (msymbol != NULL && MSYMBOL_TYPE (msymbol) == mst_solib_trampoline)
+ return msymbol;
+ return NULL;
+}
+
+/* If PC is in a shared library trampoline code stub, return the
+ address of the `real' function belonging to the stub.
+ Return 0 if PC is not in a trampoline code stub or if the real
+ function is not found in the minimal symbol table.
+
+ We may fail to find the right function if a function with the
+ same name is defined in more than one shared library, but this
+ is considered bad programming style. We could return 0 if we find
+ a duplicate function in case this matters someday. */
+
+CORE_ADDR
+find_solib_trampoline_target (pc)
+ CORE_ADDR pc;
+{
+ struct objfile *objfile;
+ struct minimal_symbol *msymbol;
+ struct minimal_symbol *tsymbol = lookup_solib_trampoline_symbol_by_pc (pc);
+
+ if (tsymbol != NULL)
+ {
+ ALL_MSYMBOLS (objfile, msymbol)
+ {
+ if (MSYMBOL_TYPE (msymbol) == mst_text
+ && STREQ (SYMBOL_NAME (msymbol), SYMBOL_NAME (tsymbol)))
+ return SYMBOL_VALUE_ADDRESS (msymbol);
}
}
+ return 0;
}