Add symbol lookup cache.

gdb/ChangeLog:

	Add symbol lookup cache.
	* NEWS: Document new options and commands.
	* symtab.c (symbol_cache_key): New static global.
	(DEFAULT_SYMBOL_CACHE_SIZE, MAX_SYMBOL_CACHE_SIZE): New macros.
	(SYMBOL_LOOKUP_FAILED): New macro.
	(symbol_cache_slot_state): New enum.
	(block_symbol_cache): New struct.
	(symbol_cache): New struct.
	(new_symbol_cache_size, symbol_cache_size): New static globals.
	(hash_symbol_entry, eq_symbol_entry): New functions.
	(symbol_cache_byte_size, resize_symbol_cache): New functions.
	(make_symbol_cache, free_symbol_cache): New functions.
	(get_symbol_cache, symbol_cache_cleanup): New function.
	(set_symbol_cache_size, set_symbol_cache_size_handler): New functions.
	(symbol_cache_lookup, symbol_cache_clear_slot): New function.
	(symbol_cache_mark_found, symbol_cache_mark_not_found): New functions.
	(symbol_cache_flush, symbol_cache_dump): New functions.
	(maintenance_print_symbol_cache): New function.
	(maintenance_flush_symbol_cache): New function.
	(symbol_cache_stats): New function.
	(maintenance_print_symbol_cache_statistics): New function.
	(symtab_new_objfile_observer): New function.
	(symtab_free_objfile_observer): New function.
	(lookup_static_symbol, lookup_global_symbol): Use symbol cache.
	(_initialize_symtab): Init symbol_cache_key.  New parameter
	maint symbol-cache-size.  New maint commands print symbol-cache,
	print symbol-cache-statistics, flush-symbol-cache.
	Install new_objfile, free_objfile observers.

doc/ChangeLog:

	* gdb.texinfo (Symbols): Document new commands
	"maint print symbol-cache", "maint print symbol-cache-statistics",
	"maint flush-symbol-cache".  Document new option
	"maint set symbol-cache-size".

2 files changed, 39 insertions, 1 deletions

diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog
index aab69f9..06e4f20 100644
--- a/gdb/doc/ChangeLog
+++ b/gdb/doc/ChangeLog
@@ -1,3 +1,10 @@
+2015-01-10  Doug Evans  <xdje42@gmail.com>
+
+	* gdb.texinfo (Symbols): Document new commands
+	"maint print symbol-cache", "maint print symbol-cache-statistics",
+	"maint flush-symbol-cache".  Document new option
+	"maint set symbol-cache-size".
+
 2014-12-31  Joel Brobecker  <brobecker@adacore.com>
 
 	* gdb.texinfo (Files): Remove documentation of the
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index f4d7132..b752524 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -16471,8 +16471,39 @@ line 1574.
 @}
 (@value{GDBP})
 @end smallexample
-@end table
 
+@kindex maint set symbol-cache-size
+@cindex symbol cache size
+@item maint set symbol-cache-size @var{size}
+Set the size of the symbol cache to @var{size}.
+The default size is intended to be good enough for debugging
+most applications.  This option exists to allow for experimenting
+with different sizes.
+
+@kindex maint show symbol-cache-size
+@item maint show symbol-cache-size
+Show the size of the symbol cache.
+
+@kindex maint print symbol-cache
+@cindex symbol cache, printing its contents
+@item maint print symbol-cache
+Print the contents of the symbol cache.
+This is useful when debugging symbol cache issues.
+
+@kindex maint print symbol-cache-statistics
+@cindex symbol cache, printing usage statistics
+@item maint print symbol-cache-statistics
+Print symbol cache usage statistics.
+This helps determine how well the cache is being utilized.
+
+@kindex maint flush-symbol-cache
+@cindex symbol cache, flushing
+@item maint flush-symbol-cache
+Flush the contents of the symbol cache, all entries are removed.
+This command is useful when debugging the symbol cache.
+It is also useful when collecting performance data.
+
+@end table
 
 @node Altering
 @chapter Altering Execution