OpenE2K/binutils-gdb
12
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Don't make an extra copy + allocation of the demangled name

Browse Source 
We can just keep around the malloc()-ed name we got from bfd and free
it later.

gdb/ChangeLog:

2019-10-25  Christian Biesinger  <cbiesinger@google.com>

	* symtab.c (struct demangled_name_entry): Change demangled name
	to a unique_xmalloc_ptr<char>, now that we don't allocate it as
	part of the struct anymore.
	(symbol_set_names): No longer obstack allocate + copy the demangled
	name, just store the allocated name from bfd.

Change-Id: Ie6ad50e1e1e73509f55d756f0a437897bb93e3b0
This commit is contained in:
Christian Biesinger 2019-10-13 06:56:58 -05:00
parent 5c49f2cd78
commit 5396ae1717
2 changed files with 21 additions and 25 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
gdb/ChangeLog
View File

@ -1,3 +1,11 @@
2019-10-25 Christian Biesinger <cbiesinger@google.com>
* symtab.c (struct demangled_name_entry): Change demangled name
to a unique_xmalloc_ptr<char>, now that we don't allocate it as
part of the struct anymore.
(symbol_set_names): No longer obstack allocate + copy the demangled
name, just store the allocated name from bfd.
2019-10-25 Tom Tromey <tromey@adacore.com>
* dwarf2-frame.c (dwarf2_cie_table): Now a typedef.

38
gdb/symtab.c
View File

@ -723,7 +723,7 @@ struct demangled_name_entry
gdb::string_view mangled;
enum language language;
char demangled[1];
gdb::unique_xmalloc_ptr<char> demangled;
};
/* Hash function for the demangled name hash. */
@ -839,7 +839,7 @@ symbol_set_names (struct general_symbol_info *gsymbol,
{
/* In Ada, we do the symbol lookups using the mangled name, so
we can save some space by not storing the demangled name. */
if (!copy_name)
if (!copy_name && linkage_name_copy == linkage_name)
gsymbol->name = linkage_name;
else
{
@ -880,20 +880,17 @@ symbol_set_names (struct general_symbol_info *gsymbol,
if (*slot == NULL
/* A C version of the symbol may have already snuck into the table.
This happens to, e.g., main.init (__go_init_main). Cope. */
|| (gsymbol->language == language_go
&& (*slot)->demangled[0] == '\0'))
|| (gsymbol->language == language_go && (*slot)->demangled == nullptr))
{
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;
gdb::unique_xmalloc_ptr<char> demangled_name_ptr
(symbol_find_demangled_name (gsymbol, linkage_name_copy));
/* Suppose we have demangled_name==NULL, copy_name==0, and
linkage_name_copy==linkage_name. In this case, we already have the
mangled name saved, and we don't have a demangled name. So,
you might think we could save a little space by not recording
this in the hash table at all.
It turns out that it is actually important to still save such
an entry in the hash table, because storing this name gives
us better bcache hit rates for partial symbols. */
@ -902,42 +899,33 @@ 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)));
new (*slot) demangled_name_entry
(gdb::string_view (linkage_name, len));
}
else
{
char *mangled_ptr;
/* If we must copy the mangled name, put it directly after
the demangled name so we can have a single
allocation. */
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);
new (*slot) demangled_name_entry
(gdb::string_view (mangled_ptr, len));
}
(*slot)->demangled = std::move (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.data ();
if ((*slot)->demangled[0] != '\0')
symbol_set_demangled_name (gsymbol, (*slot)->demangled,
if ((*slot)->demangled != nullptr)
symbol_set_demangled_name (gsymbol, (*slot)->demangled.get (),
&per_bfd->storage_obstack);
else
symbol_set_demangled_name (gsymbol, NULL, &per_bfd->storage_obstack);