gdb: introduce new 'maint flush ' prefix command

We currently have two flushing commands 'flushregs' and 'maint
flush-symbol-cache'.  I'm planning to add at least one more so I
thought it might be nice if we bundled these together into one place.

And so I created the 'maint flush ' command prefix.  Currently there
are two commands:

  (gdb) maint flush symbol-cache
  (gdb) maint flush register-cache

Unfortunately, even though both of the existing flush commands are
maintenance commands, I don't know how keen we about deleting existing
commands for fear of breaking things in the wild.  So, both of the
existing flush commands 'maint flush-symbol-cache' and 'flushregs' are
still around as deprecated aliases to the new commands.

I've updated the testsuite to use the new command syntax, and updated
the documentation too.

gdb/ChangeLog:

	* NEWS: Mention new commands, and that the old commands are now
	deprecated.
	* cli/cli-cmds.c (maintenanceflushlist): Define.
	* cli/cli-cmds.h (maintenanceflushlist): Declare.
	* maint.c (_initialize_maint_cmds): Initialise
	maintenanceflushlist.
	* regcache.c: Add 'cli/cli-cmds.h' include.
	(reg_flush_command): Add header comment.
	(_initialize_regcache): Create new 'maint flush register-cache'
	command, make 'flushregs' an alias.
	* symtab.c: Add 'cli/cli-cmds.h' include.
	(_initialize_symtab): Create new 'maint flush symbol-cache'
	command, make old command an alias.

gdb/doc/ChangeLog:

	* gdb.texinfo (Symbols): Document 'maint flush symbol-cache'.
	(Maintenance Commands): Document 'maint flush register-cache'.

gdb/testsuite/ChangeLog:

	* gdb.base/c-linkage-name.exp: Update to use new 'maint flush ...'
	commands.
	* gdb.base/killed-outside.exp: Likewise.
	* gdb.opt/inline-bt.exp: Likewise.
	* gdb.perf/gmonster-null-lookup.py: Likewise.
	* gdb.perf/gmonster-print-cerr.py: Likewise.
	* gdb.perf/gmonster-ptype-string.py: Likewise.
	* gdb.python/py-unwind.exp: Likewise.

2 files changed, 21 insertions, 6 deletions

diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog
index 5793ab9..6ad728e 100644
--- a/gdb/doc/ChangeLog
+++ b/gdb/doc/ChangeLog
@@ -1,3 +1,8 @@
+2020-12-13  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* gdb.texinfo (Symbols): Document 'maint flush symbol-cache'.
+	(Maintenance Commands): Document 'maint flush register-cache'.
+
 2020-12-04  Bernd Edlinger  <bernd.edlinger@hotmail.de>
 
 	* Makefile.in: Delete GDBvn.texi and version.subst only in
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 01dcac9..5bafb9d 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -19503,12 +19503,16 @@ This is useful when debugging symbol cache issues.
 Print symbol cache usage statistics.
 This helps determine how well the cache is being utilized.
 
+@kindex maint flush symbol-cache
 @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.
+@item maint flush symbol-cache
+@itemx 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.  The command @code{maint
+flush-symbol-cache} is deprecated in favor of @code{maint flush
+symbol-cache}..
 
 @end table
 
@@ -38859,9 +38863,15 @@ The register groups info looks like this:
  restore    internal
 @end smallexample
 
+@kindex maint flush register-cache
 @kindex flushregs
-@item flushregs
-This command forces @value{GDBN} to flush its internal register cache.
+@cindex register cache, flushing
+@item maint flush register-cache
+@itemx flushregs
+Flush the contents of the register cache and as a consequence the
+frame cache.  This command is useful when debugging issues related to
+register fetching, or frame unwinding.  The command @code{flushregs}
+is deprecated in favor of @code{maint flush register-cache}.
 
 @kindex maint print objfiles
 @cindex info for known object files