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Re: [PATCH] -stack-select-frame
On Jun 16, 2005, at 4:05 PM, Nick Roberts wrote:
I thought it would save some time if the user doesn't need to see the
whole stack.
FWIW we've done a lot of careful timing analysis, and the back &
forth communication between our GUI and gdb is so fast as to be
pointless to optimize. We original considered adding special purpose
"give Xcode everything it needs to know at a breakpoint hit" type
commands but when we saw how fast the majority of MI commands can
execute & be parsed by the GUI, it was obvious that this was not a
useful area to optimize. And frankly, in my anecdotal experience,
MacOS X isn't the fastest OS at things like "two processes talking
over a pipe".
(one of the parts of this profiling which is especially useful is
that we have a "mi-timings-enabled" setting. When it's enabled,
every MI command reports how long gdb took to complete it, e.g. the
"time=" bit at the end here:
-> 50-stack-list-frames 0 5
<- 50^done,stack=[frame=
{level="0",addr="0x0009e7fc",fp="0xbfffe700",func=" [...] ,frame=
{level="5",addr="0x936265d0",fp="0xbfffeee0",func="-[NSApplication
run]"}],time=
{wallclock="0.14353",user="0.00584",system="0.00335",start="1118952348.0
03847",end="1118952348.147372"}
we have similar timestamps put out by the GUI so when there's a
slowdown we can establish where time was being spent.)
enum mi_cmd_result
mi_cmd_stack_select_frame (char *command, char **argv, int argc)
{
- if (!target_has_stack)
- error (_("mi_cmd_stack_select_frame: No stack."));
-
Because now GDB will report it as follows:
-stack-select-frame
&"No stack.\n"
^error,msg="No stack."
(gdb)
You're right, currently it behaves like this:
-stack-select-frame
&"mi_cmd_stack_select_frame: No stack.\n"
^error,msg="mi_cmd_stack_select_frame: No stack."
(gdb)
but select_frame_command () will throw the error eventually, so
there's no need to do the additional check here.
J