Don't make an extra copy + allocation of the demangled name
Commit Message
We can just keep around the malloc()-ed name we got from bfd and free
it later.
gdb/ChangeLog:
2019-10-02 Christian Biesinger <cbiesinger@google.com>
* symtab.c (struct demangled_name_entry): Change demangled name
to a char*, now that we don't allocate it as part of the struct
anymore.
(free_demangled_name_entry): New function.
(create_demangled_names_hash): Pass free function to htab_create_alloc.
(symbol_set_names): No longer obstack allocate + copy the demangled
name, just store the allocated name from bfd.
---
gdb/symtab.c | 35 +++++++++++++++++------------------
1 file changed, 17 insertions(+), 18 deletions(-)
@@ -715,7 +715,7 @@ struct demangled_name_entry
{
const char *mangled;
ENUM_BITFIELD(language) language : LANGUAGE_BITS;
- char demangled[1];
+ char* demangled;
};
/* Hash function for the demangled name hash. */
@@ -742,6 +742,15 @@ eq_demangled_name_entry (const void *a, const void *b)
return strcmp (da->mangled, db->mangled) == 0;
}
+static void
+free_demangled_name_entry (void *data)
+{
+ struct demangled_name_entry *e
+ = (struct demangled_name_entry *) data;
+
+ xfree (e->demangled);
+}
+
/* Create the hash table used for demangled names. Each hash entry is
a pair of strings; one for the mangled name and one for the demangled
name. The entry is hashed via just the mangled name. */
@@ -756,7 +765,7 @@ create_demangled_names_hash (struct objfile_per_bfd_storage *per_bfd)
per_bfd->demangled_names_hash.reset (htab_create_alloc
(256, hash_demangled_name_entry, eq_demangled_name_entry,
- NULL, xcalloc, xfree));
+ free_demangled_name_entry, xcalloc, xfree));
}
/* Try to determine the demangled name for a symbol, based on the
@@ -869,8 +878,6 @@ symbol_set_names (struct general_symbol_info *gsymbol,
{
char *demangled_name_ptr
= symbol_find_demangled_name (gsymbol, linkage_name_copy);
- gdb::unique_xmalloc_ptr<char> demangled_name (demangled_name_ptr);
- int demangled_len = demangled_name ? strlen (demangled_name.get ()) : 0;
/* Suppose we have demangled_name==NULL, copy_name==0, and
linkage_name_copy==linkage_name. In this case, we already have the
@@ -886,39 +893,31 @@ symbol_set_names (struct general_symbol_info *gsymbol,
*slot
= ((struct demangled_name_entry *)
obstack_alloc (&per_bfd->storage_obstack,
- offsetof (struct demangled_name_entry, demangled)
- + demangled_len + 1));
+ sizeof (demangled_name_entry)));
(*slot)->mangled = linkage_name;
}
else
{
- char *mangled_ptr;
-
/* If we must copy the mangled name, put it directly after
- the demangled name so we can have a single
+ the struct so we can have a single
allocation. */
*slot
= ((struct demangled_name_entry *)
obstack_alloc (&per_bfd->storage_obstack,
- offsetof (struct demangled_name_entry, demangled)
- + len + demangled_len + 2));
- mangled_ptr = &((*slot)->demangled[demangled_len + 1]);
+ sizeof (demangled_name_entry) + len + 1));
+ char *mangled_ptr = reinterpret_cast<char*> (*slot + 1);
strcpy (mangled_ptr, linkage_name_copy);
(*slot)->mangled = mangled_ptr;
}
+ (*slot)->demangled = demangled_name_ptr;
(*slot)->language = gsymbol->language;
-
- if (demangled_name != NULL)
- strcpy ((*slot)->demangled, demangled_name.get ());
- else
- (*slot)->demangled[0] = '\0';
}
else if (gsymbol->language == language_unknown
|| gsymbol->language == language_auto)
gsymbol->language = (*slot)->language;
gsymbol->name = (*slot)->mangled;
- if ((*slot)->demangled[0] != '\0')
+ if ((*slot)->demangled != nullptr)
symbol_set_demangled_name (gsymbol, (*slot)->demangled,
&per_bfd->storage_obstack);
else