diff mbox

[PATCHv4] gdb: Change how frames are selected for 'frame' and 'info frame'.

Message ID 20180717155751.30898-1-andrew.burgess@embecosm.com
State New
Headers show

Commit Message

Andrew Burgess July 17, 2018, 3:57 p.m. UTC
Now that the 'frame apply' command has been merged to master, this is
a rebase of the v3 patch.  Merge conflicts have been resolved, but the
content is largely unchanged.

Thanks,
Andrew

---

The 'frame' command, and thanks to code reuse the 'info frame' and
'select-frame' commands, currently have an overloaded mechanism for
selecting a frame.

These commands take one or two parameters, if it's one parameter then
we first try to use the parameter as an integer to select a frame by
level (or depth in the stack).  If that fails then we treat the
parameter as an address and try to select a stack frame by
stack-address.  If we still have not selected a stack frame, or we
initially had two parameters, then GDB allows the user to view a stack
frame that is not part of the current backtrace.  Internally, a new
frame is created with the given stack and pc addresses, and this is
shown to the user.

The result of this is that a typo by the user, entering the wrong stack
frame level for example, can result in a brand new frame being viewed
rather than an error.

The purpose of this commit is to remove this overloading, while still
offering the same functionality through some new sub-commands.  By
making the default behaviour of 'frame' (and friends) be to select a
stack frame by level number, it is hoped that enough
backwards-compatibility is maintained that users will not be overly
inconvenienced.

The 'frame', 'select-frame', and 'info frame' commands now all take a
frame specification string as an argument, this string can be any of the
following:

  (1) An integer.  This is treated as a frame number.  If a frame for
  that number does not exist then the user gets an error.

  (2) A string like 'level <NUMBER>', where <NUMBER> is a frame number
  as in option (1) above.

  (3) A string like 'address <ADDRESS>', where <ADDRESS> is a
  stack-frame address.  If there is no frame for this address then the
  user gets an error.

  (4) A string like 'function <NAME>', where <NAME> is a function name,
  the inner most frame for function <NAME> is selected.  If there is no
  frame for function <NAME> then the user gets an error.

  (5) A string like 'view <STACK-ADDRESS>', this views a new frame
  with stack address <STACK-ADDRESS>.

  (6) A string like 'view <STACK-ADDRESS> <PC-ADDRESS>', this views
  a new frame with stack address <STACK-ADDRESS> an the pc <PC-ADDRESS>.

This change assumes that the most common use of the commands like
'frame' is to select a frame by frame level number, it is for this
reason that this is the behaviour that is kept for backwards
compatibility.  Any of the alternative behaviours, which are assumed to
be less used, now require a change in user behaviour.

The MI command '-stack-select-frame' has also changed in the same way.
The default behaviour is to select a frame by level number, but the
other selection methods are also available.

gdb/ChangeLog:

	(NEWS): Mention changes to frame related commands.
	* cli/cli-decode.c (add_cmd_suppress_notification): New function.
	(add_prefix_cmd_suppress_notification): New function.
	(add_com_suppress_notification): Call
	add_cmd_suppress_notification.
	* command.h (add_cmd_suppress_notification): Declare.
	(add_prefix_cmd_suppress_notification): Declare.
	* mi/mi-cmd-stack.c (mi_cmd_stack_select_frame): Use new function
	select_frame_from_spec.
	* stack.c (find_frame_for_function): Add declaration.
	(find_frame_for_address): New function.
	(parse_frame_specification): Delete function.
	(frame_selection_by_function_completer): New function.
	(info_frame_command): Rename to...
	(info_frame_command_core): ...this, and update parameter types.
	(select_frame_command): Rename to...
	(select_frame_command_core): ...this, and update parameter types.
	(frame_command): Rename to...
	(frame_command_core): ...this, and update parameter types.
	(class frame_command_helper): New class to wrap implementations of
	frame related sub-commands.
	(select_frame_from_spec): New function.
	(frame_apply_cmd_list): New static global.
	(frame_cmd_list): Make static.
	(select_frame_cmd_list): New global for sub-commands.
	(info_frame_cmd_list): New global for sub-commands.
	(_initialize_stack): Register sub-commands for 'frame',
	'select-frame', and 'info frame'.  Update 'frame apply' commands
	to use frame_apply_cmd_list.  Move function local static
	frame_apply_list to file static frame_apply_cmd_list for
	consistency.
	* stack.h (select_frame_command): Delete declarationn.
	(select_frame_from_spec): Declare new function.

gdb/doc/ChangeLog:

	* gdb.texinfo (Selection): Rewrite documentation for 'frame' and
	'select-frame' commands.
	(Frame Info): Rewrite documentation for 'info frame' command.
	(GDB/MI Stack Manipulation): Update description of
	'-stack-select-frame'.

gdb/testsuite/ChangeLog:

	* gdb.base/frame-selection.exp: New file.
	* gdb.base/frame-selection.c: New file.
	* gdb.mi/mi-frame-selection.exp: New file.
	* gdb.mi/mi-frame-selection.c: New file.
---
 gdb/ChangeLog                               |  36 ++
 gdb/NEWS                                    |   8 +
 gdb/cli/cli-decode.c                        |  44 ++-
 gdb/command.h                               |  14 +
 gdb/doc/ChangeLog                           |   8 +
 gdb/doc/gdb.texinfo                         |  89 +++--
 gdb/mi/mi-cmd-stack.c                       |   4 +-
 gdb/stack.c                                 | 535 +++++++++++++++++++---------
 gdb/stack.h                                 |   2 +-
 gdb/testsuite/ChangeLog                     |   7 +
 gdb/testsuite/gdb.base/frame-selection.c    |  52 +++
 gdb/testsuite/gdb.base/frame-selection.exp  | 157 ++++++++
 gdb/testsuite/gdb.mi/mi-frame-selection.c   |  34 ++
 gdb/testsuite/gdb.mi/mi-frame-selection.exp |  89 +++++
 14 files changed, 877 insertions(+), 202 deletions(-)
 create mode 100644 gdb/testsuite/gdb.base/frame-selection.c
 create mode 100644 gdb/testsuite/gdb.base/frame-selection.exp
 create mode 100644 gdb/testsuite/gdb.mi/mi-frame-selection.c
 create mode 100644 gdb/testsuite/gdb.mi/mi-frame-selection.exp

Comments

Philippe Waroquiers July 23, 2018, 8:45 p.m. UTC | #1
On Tue, 2018-07-17 at 16:57 +0100, Andrew Burgess wrote:
> Now that the 'frame apply' command has been merged to master, this is
> a rebase of the v3 patch.  Merge conflicts have been resolved, but the
> content is largely unchanged.
FWIW, I like the idea of the patch, as it is too easy to
(too silently) get a wrong frame with 'frame <a wrong frame level/number>'.

Find below some comments to discuss the terminology 'frame level'
versus 'frame number'.

Philippe

> 
> Thanks,
> Andrew
> 
> ---
> 
> The 'frame' command, and thanks to code reuse the 'info frame' and
> 'select-frame' commands, currently have an overloaded mechanism for
> selecting a frame.
> 
> These commands take one or two parameters, if it's one parameter then
> we first try to use the parameter as an integer to select a frame by
> level (or depth in the stack).  If that fails then we treat the
> parameter as an address and try to select a stack frame by
> stack-address.  If we still have not selected a stack frame, or we
> initially had two parameters, then GDB allows the user to view a stack
> frame that is not part of the current backtrace.  Internally, a new
> frame is created with the given stack and pc addresses, and this is
> shown to the user.
> 
> The result of this is that a typo by the user, entering the wrong stack
> frame level for example, can result in a brand new frame being viewed
> rather than an error.
> 
> The purpose of this commit is to remove this overloading, while still
> offering the same functionality through some new sub-commands.  By
> making the default behaviour of 'frame' (and friends) be to select a
> stack frame by level number, it is hoped that enough
> backwards-compatibility is maintained that users will not be overly
> inconvenienced.
> 
> The 'frame', 'select-frame', and 'info frame' commands now all take a
> frame specification string as an argument, this string can be any of the
> following:
> 
>   (1) An integer.  This is treated as a frame number.  If a frame for
>   that number does not exist then the user gets an error.
> 
>   (2) A string like 'level <NUMBER>', where <NUMBER> is a frame number
>   as in option (1) above.

I did a trial to scan the documentation for the usage of 'frame number',
in order to replace it by 'frame level'.
Note that Eli has some reserve about this idea/replacement,
see thread https://sourceware.org/ml/gdb-patches/2018-07/msg00365.html.

IMO, the sentences (1) and (2) above should preferably
use consistently 'frame level' 'level <LEVEL>' : at the moment,
we seem to semi-randomly use level or number, explaining at some places
that level is a frame number. 

It would be good to clarify exactly what naming convention should
be used, and apply it (more) systematically (in the existing
documentation and/or in this patch).



>   (3) A string like 'address <ADDRESS>', where <ADDRESS> is a
>   stack-frame address.  If there is no frame for this address then the
>   user gets an error.
Below, (5) and (6) are using STACK-ADDRESS instead of ADDRESS.
I am not sure to understand if there is (or not) a difference of concept
between this ADDRESS and the below STACK-ADDRESS.
I am wondering which address we are speaking about.
When doing 'info frame', I get something like:
  (gdb) info frame
  Stack level 1, frame at 0x7fffffffdf80:
   rip = 0x555555554f5e in sleeper_or_burner (sleepers.c:86); saved rip = 0x55555555549d
   called by frame at 0x7fffffffe040, caller of frame at 0x7fffffffdf40
   source language c.
   Arglist at 0x7fffffffdf70, args: v=0x7fffffffdf90
   Locals at 0x7fffffffdf70, Previous frame's sp is 0x7fffffffdf80
   Saved registers:
    rbp at 0x7fffffffdf70, rip at 0x7fffffffdf78
  (gdb) 
Maybe it would be good to reference in the doc the field given
in the above output ?


Note that the above command output uses 'Stack level 1',
and not 'Stack number 1' :).


> 
>   (4) A string like 'function <NAME>', where <NAME> is a function name,
>   the inner most frame for function <NAME> is selected.  If there is no
>   frame for function <NAME> then the user gets an error.
> 
>   (5) A string like 'view <STACK-ADDRESS>', this views a new frame
>   with stack address <STACK-ADDRESS>.
> 
>   (6) A string like 'view <STACK-ADDRESS> <PC-ADDRESS>', this views
>   a new frame with stack address <STACK-ADDRESS> an the pc <PC-ADDRESS>.
> 
> This change assumes that the most common use of the commands like
> 'frame' is to select a frame by frame level number, it is for this
> reason that this is the behaviour that is kept for backwards
> compatibility.  Any of the alternative behaviours, which are assumed to
> be less used, now require a change in user behaviour.
> 
> The MI command '-stack-select-frame' has also changed in the same way.
> The default behaviour is to select a frame by level number, but the
> other selection methods are also available.

In the rest of the patch, assuming there is an agreement about
using frame level instead of frame number, there are some other
occurrences of number to replace/clarify.

Philippe
Andrew Burgess July 25, 2018, 6:14 p.m. UTC | #2
* Philippe Waroquiers <philippe.waroquiers@skynet.be> [2018-07-23 22:45:55 +0200]:

> On Tue, 2018-07-17 at 16:57 +0100, Andrew Burgess wrote:
> > Now that the 'frame apply' command has been merged to master, this is
> > a rebase of the v3 patch.  Merge conflicts have been resolved, but the
> > content is largely unchanged.
> FWIW, I like the idea of the patch, as it is too easy to
> (too silently) get a wrong frame with 'frame <a wrong frame level/number>'.
> 
> Find below some comments to discuss the terminology 'frame level'
> versus 'frame number'.
> 
> Philippe
> 
> > 
> > Thanks,
> > Andrew
> > 
> > ---
> > 
> > The 'frame' command, and thanks to code reuse the 'info frame' and
> > 'select-frame' commands, currently have an overloaded mechanism for
> > selecting a frame.
> > 
> > These commands take one or two parameters, if it's one parameter then
> > we first try to use the parameter as an integer to select a frame by
> > level (or depth in the stack).  If that fails then we treat the
> > parameter as an address and try to select a stack frame by
> > stack-address.  If we still have not selected a stack frame, or we
> > initially had two parameters, then GDB allows the user to view a stack
> > frame that is not part of the current backtrace.  Internally, a new
> > frame is created with the given stack and pc addresses, and this is
> > shown to the user.
> > 
> > The result of this is that a typo by the user, entering the wrong stack
> > frame level for example, can result in a brand new frame being viewed
> > rather than an error.
> > 
> > The purpose of this commit is to remove this overloading, while still
> > offering the same functionality through some new sub-commands.  By
> > making the default behaviour of 'frame' (and friends) be to select a
> > stack frame by level number, it is hoped that enough
> > backwards-compatibility is maintained that users will not be overly
> > inconvenienced.
> > 
> > The 'frame', 'select-frame', and 'info frame' commands now all take a
> > frame specification string as an argument, this string can be any of the
> > following:
> > 
> >   (1) An integer.  This is treated as a frame number.  If a frame for
> >   that number does not exist then the user gets an error.
> > 
> >   (2) A string like 'level <NUMBER>', where <NUMBER> is a frame number
> >   as in option (1) above.
> 
> I did a trial to scan the documentation for the usage of 'frame number',
> in order to replace it by 'frame level'.
> Note that Eli has some reserve about this idea/replacement,
> see thread
> https://sourceware.org/ml/gdb-patches/2018-07/msg00365.html.

I seem to have opened a can of works with the choice of level here.

It's been a while since I wrote the original patch (almost 3 years)
so, honestly, I can't recall why I picked 'level' over 'number'.  It
probably seemed more descriptive at the time, but honestly I would be
just as happy to use 'number' instead.

So, what I'd really like is some guidance from .... well .... anyone
who cares really .... level or number ?

Thanks,
Andrew








> 
> IMO, the sentences (1) and (2) above should preferably
> use consistently 'frame level' 'level <LEVEL>' : at the moment,
> we seem to semi-randomly use level or number, explaining at some places
> that level is a frame number. 
> 
> It would be good to clarify exactly what naming convention should
> be used, and apply it (more) systematically (in the existing
> documentation and/or in this patch).
> 
> 
> 
> >   (3) A string like 'address <ADDRESS>', where <ADDRESS> is a
> >   stack-frame address.  If there is no frame for this address then the
> >   user gets an error.
> Below, (5) and (6) are using STACK-ADDRESS instead of ADDRESS.
> I am not sure to understand if there is (or not) a difference of concept
> between this ADDRESS and the below STACK-ADDRESS.
> I am wondering which address we are speaking about.
> When doing 'info frame', I get something like:
>   (gdb) info frame
>   Stack level 1, frame at 0x7fffffffdf80:
>    rip = 0x555555554f5e in sleeper_or_burner (sleepers.c:86); saved rip = 0x55555555549d
>    called by frame at 0x7fffffffe040, caller of frame at 0x7fffffffdf40
>    source language c.
>    Arglist at 0x7fffffffdf70, args: v=0x7fffffffdf90
>    Locals at 0x7fffffffdf70, Previous frame's sp is 0x7fffffffdf80
>    Saved registers:
>     rbp at 0x7fffffffdf70, rip at 0x7fffffffdf78
>   (gdb) 
> Maybe it would be good to reference in the doc the field given
> in the above output ?
> 
> 
> Note that the above command output uses 'Stack level 1',
> and not 'Stack number 1' :).
> 
> 
> > 
> >   (4) A string like 'function <NAME>', where <NAME> is a function name,
> >   the inner most frame for function <NAME> is selected.  If there is no
> >   frame for function <NAME> then the user gets an error.
> > 
> >   (5) A string like 'view <STACK-ADDRESS>', this views a new frame
> >   with stack address <STACK-ADDRESS>.
> > 
> >   (6) A string like 'view <STACK-ADDRESS> <PC-ADDRESS>', this views
> >   a new frame with stack address <STACK-ADDRESS> an the pc <PC-ADDRESS>.
> > 
> > This change assumes that the most common use of the commands like
> > 'frame' is to select a frame by frame level number, it is for this
> > reason that this is the behaviour that is kept for backwards
> > compatibility.  Any of the alternative behaviours, which are assumed to
> > be less used, now require a change in user behaviour.
> > 
> > The MI command '-stack-select-frame' has also changed in the same way.
> > The default behaviour is to select a frame by level number, but the
> > other selection methods are also available.
> 
> In the rest of the patch, assuming there is an agreement about
> using frame level instead of frame number, there are some other
> occurrences of number to replace/clarify.
> 
> Philippe
>
Andrew Burgess Aug. 13, 2018, 10:20 p.m. UTC | #3
Given a lack of feedback on v4, I've put together two alternative
versions to pick between...

  (A) In this version I took onboard the feedback from Eli and
      Philippe that using "level" might be confusing to users, as
      "number" is historically what has been used for the integer
      label we give to frames.

      The command for selecting a frame by integer is now, 'frame
      number <NUMBER>' and almost all references to "level" have now
      been removed from the patch.

  (B) In this version I've taken onboard the advice from Philippe,
      identifying places in the patch where I was mixing use of
      "level" and "number".  I've doubled down on "level" and removed
      most uses of "number" from the patch.

If we select patch 'A' then me might want to update 'frame apply level
...' to 'frame apply number ...' for consistency.

If we select patch 'B' then we will probably need a follow up patch
that goes through the documentation to tighten up references to
"number" vs "level".

I really don't mind which approach we take, I guess I'd probably pick
'B' over 'A' given we already have 'frame apply level ...' in GDB, but
if there's preference for 'A' then that's fine.

I'm also happy to do the follow up patches once we have some agreement
on which way to go.

Thanks,
Andrew

---

Andrew Burgess (1):
  gdb: Change how frames are selected for 'frame' and 'info frame'.

 gdb/ChangeLog                               |  36 ++
 gdb/NEWS                                    |   8 +
 gdb/cli/cli-decode.c                        |  44 ++-
 gdb/command.h                               |  14 +
 gdb/doc/ChangeLog                           |   8 +
 gdb/doc/gdb.texinfo                         | 108 ++++--
 gdb/mi/mi-cmd-stack.c                       |   4 +-
 gdb/stack.c                                 | 535 +++++++++++++++++++---------
 gdb/stack.h                                 |   2 +-
 gdb/testsuite/ChangeLog                     |   7 +
 gdb/testsuite/gdb.base/frame-selection.c    |  52 +++
 gdb/testsuite/gdb.base/frame-selection.exp  | 157 ++++++++
 gdb/testsuite/gdb.mi/mi-frame-selection.c   |  34 ++
 gdb/testsuite/gdb.mi/mi-frame-selection.exp |  89 +++++
 14 files changed, 896 insertions(+), 202 deletions(-)
 create mode 100644 gdb/testsuite/gdb.base/frame-selection.c
 create mode 100644 gdb/testsuite/gdb.base/frame-selection.exp
 create mode 100644 gdb/testsuite/gdb.mi/mi-frame-selection.c
 create mode 100644 gdb/testsuite/gdb.mi/mi-frame-selection.exp
Philippe Waroquiers Aug. 14, 2018, 10:31 a.m. UTC | #4
On Mon, 2018-08-13 at 23:20 +0100, Andrew Burgess wrote:
> Given a lack of feedback on v4, I've put together two alternative
> versions to pick between...
> 
>   (A) In this version I took onboard the feedback from Eli and
>       Philippe that using "level" might be confusing to users, as
>       "number" is historically what has been used for the integer
>       label we give to frames.

What I find confusing is to have the same concept
('frame something_identifying_a_frame')
be called sometimes 'frame number' and sometimes 'frame level'.

My personal preference is to use 'frame level' because:
  * IMO, frame level better matches a stack/backtrace concept than the
    very general frame number (and number is overloaded e.g.
    in 'number of frames').
  * frame number is used for another concept (traceframe number,
    but without always using trace word.  E.g. the MI interface uses
    frame-number for 'frame something_identifying_a_traceframe'),
    which has (IIUC) not much to do with a backtrace frame.
  * there are a lot more usages of 'frame level' that 'frame number'
    (see below the result of analysing some grep 'frame/number/level'
    on the code and on the documentation).
    From what I can see, we have less than 20 occurrences of using
    number for a frame 'something', and we have a lot more places (80?)
    where the wording level is used for a frame 'something'
    (about 20 being the usage of frame_relative_level function).
  * I think we can (mostly?) fix all the inconsitencies by
    switching to frame level for a backtrace frame something,
    while I think it is (mostly?) desperate to fix the inconsistencies
    created by 'frame number' (due e.g. to MI using frame number for
    trace frame number').
    

> 
>       The command for selecting a frame by integer is now, 'frame
>       number <NUMBER>' and almost all references to "level" have now
>       been removed from the patch.
> 
>   (B) In this version I've taken onboard the advice from Philippe,
>       identifying places in the patch where I was mixing use of
>       "level" and "number".  I've doubled down on "level" and removed
>       most uses of "number" from the patch.
> 
> If we select patch 'A' then me might want to update 'frame apply level
> ...' to 'frame apply number ...' for consistency.
As indicated above, I prefer 'frame level', but no problem for me
to do a patch to change 'frame apply level' to 'frame apply number'
if that is what is decided).

> 
> If we select patch 'B' then we will probably need a follow up patch
> that goes through the documentation to tighten up references to
> "number" vs "level".
> 
> I really don't mind which approach we take, I guess I'd probably pick
> 'B' over 'A' given we already have 'frame apply level ...' in GDB, but
> if there's preference for 'A' then that's fine.
> 
> I'm also happy to do the follow up patches once we have some agreement
> on which way to go.
> 
> Thanks,
> Andrew
> 
> ---
> 
> Andrew Burgess (1):
>   gdb: Change how frames are selected for 'frame' and 'info frame'.
> 
>  gdb/ChangeLog                               |  36 ++
>  gdb/NEWS                                    |   8 +
>  gdb/cli/cli-decode.c                        |  44 ++-
>  gdb/command.h                               |  14 +
>  gdb/doc/ChangeLog                           |   8 +
>  gdb/doc/gdb.texinfo                         | 108 ++++--
>  gdb/mi/mi-cmd-stack.c                       |   4 +-
>  gdb/stack.c                                 | 535 +++++++++++++++++++---------
>  gdb/stack.h                                 |   2 +-
>  gdb/testsuite/ChangeLog                     |   7 +
>  gdb/testsuite/gdb.base/frame-selection.c    |  52 +++
>  gdb/testsuite/gdb.base/frame-selection.exp  | 157 ++++++++
>  gdb/testsuite/gdb.mi/mi-frame-selection.c   |  34 ++
>  gdb/testsuite/gdb.mi/mi-frame-selection.exp |  89 +++++
>  14 files changed, 896 insertions(+), 202 deletions(-)
>  create mode 100644 gdb/testsuite/gdb.base/frame-selection.c
>  create mode 100644 gdb/testsuite/gdb.base/frame-selection.exp
>  create mode 100644 gdb/testsuite/gdb.mi/mi-frame-selection.c
>  create mode 100644 gdb/testsuite/gdb.mi/mi-frame-selection.exp
> 

Usages of level:
---------------

It is used in the info frame output:
(gdb) info frame
Stack level 1, frame at 0x7fffffffdf90:
 rip = 0x555555554f5e in sleeper_or_burner (sleepers.c:86); saved rip = 0x55555555549d
 called by frame at 0x7fffffffe050, caller of frame at 0x7fffffffdf50
 source language c.
 Arglist at 0x7fffffffdf80, args: v=0x7fffffffdfa0
 Locals at 0x7fffffffdf80, Previous frame's sp is 0x7fffffffdf90
 Saved registers:
  rbp at 0x7fffffffdf80, rip at 0x7fffffffdf88
(gdb)

infcmd.c:2023:      /* Print info on the selected frame, including level number but not
stack.c:2192:/* Find a frame a certain number of levels away from FRAME.
ada-lang.h:57:/* The maximum number of frame levels searched for non-local,
ada-lang.h:60:#define MAX_ENCLOSING_FRAME_LEVELS 7
defs.h:595:extern void (*selected_frame_level_changed_hook) (int);
    Obsolete ? I cannot find any reference to selected_frame_level_changed_hook.
extension.h:88:    /* Set this flag if frame level is to be printed.  */

frame.h:502:/* The frame's level: 0 for innermost, 1 for its caller, ...; or -1
frame.h:504:extern int frame_relative_level (struct frame_info *fi);
gdbthread.h:640:  int m_selected_frame_level;
stack.h:23:void select_frame_command (const char *level_exp, int from_tty);
ada-lang.c:12221:  int frame_level;
ada-lang.c:12230:  for (frame_level = 0; frame_level < 3; frame_level += 1)
ada-tasks.c:1339:                     frame_relative_level (get_selected_frame (NULL)),
amd64-tdep.c:2852:  if (frame_relative_level (this_frame) == 0)
annotate.c:435:annotate_frame_begin (int level, struct gdbarch *gdbarch, CORE_ADDR pc)
arm-tdep.c:2778:  if (frame_relative_level (this_frame) == 0)
dwarf2-frame-tailcall.c:175:  int retval = (frame_relative_level (this_frame)
dwarf2-frame-tailcall.c:176:		- frame_relative_level (cache->next_bottom_frame) - 1);

frame.c:87:  /* Level of this frame.  The inner-most (youngest) frame is at level
frame.c:88:     0.  As you move towards the outer-most (oldest) frame, the level
.... there are about 30 occurences of level in frame.c

hppa-tdep.c:1888:      frame_relative_level(this_frame));
hppa-tdep.c:2337:			frame_relative_level (this_frame));
i386-tdep.c:2236:  if (frame_relative_level (this_frame) == 0)
i386-tdep.c:2391:  if (frame_relative_level (this_frame) == 0)

infcmd.c:2023:      /* Print info on the selected frame, including level number but not
infcmd.c:2039:  /* Print info on the selected frame, including level number but not
microblaze-tdep.c:392:  if (frame_relative_level (next_frame) >= 0)
mips-tdep.c:1395:  if (frame_relative_level (next_frame) >= 0 && mips_in_frame_stub (pc))
nds32-tdep.c:1299:  if (frame_relative_level (this_frame) == 0)
or1k-tdep.c:539:			frame_relative_level (next_frame));
or1k-tdep.c:559:			frame_relative_level (next_frame));
rs6000-tdep.c:3443:  if (frame_relative_level (this_frame) == 0)

stack.c:1690:/* Return the innermost frame at level LEVEL.  */
stack.c:1693:leading_innermost_frame (int level)
... stack.c contains a lot of other occurences (some due to the new GDB 8.3
   frame apply level

value.c:3827:	 so that the frame level will be shown correctly.  */
value.c:3835:			  frame_relative_level (frame), regnum,

thread.c:1285:			       /* For MI output, print frame level.  */
thread.c:1403:restore_selected_frame (struct frame_id a_frame_id, int frame_level)
thread.c:1409:  if (frame_level == -1)
thread.c:1415:  gdb_assert (frame_level >= 0);
thread.c:1421:  count = frame_level;
thread.c:1449:  if (frame_level > 0 && !current_uiout->is_mi_like_p ())
thread.c:1453:	       frame_level);
thread.c:1487:    restore_selected_frame (m_selected_frame_id, m_selected_frame_level);
thread.c:1521:      m_selected_frame_level = frame_relative_level (frame);

python/py-framefilter.c:734:    (in the case of elided frames), and LEVELS_PRINTED is a hash-table
python/py-framefilter.c:735:    containing all the frames level that have already been printed.
python/py-framefilter.c:736:    If a frame level has been printed, do not print it again (in the
python/py-framefilter.c:818:  /* Print frame level.  MI does not require the level if
python/py-framefilter.c:828:      level = frame_relative_level (frame);
python/py-framefilter.c:839:	  annotate_frame_begin (print_level ? level : 0,


It looks like btrace.h uses level for a btrace frame, but the outermost frame
is numbered 0 (so the other way around as in backtrace command).
  /* The function level in a back trace across the entire branch trace.
     A caller's level is one lower than the level of its callee.
record-btrace.c:1759:  DEBUG ("[frame] unwound PC in %s on level %d: %s",
record-btrace.c:1809:  DEBUG ("[frame] sniffed frame for %s on level %d",
record-btrace.c:1851:  DEBUG ("[frame] sniffed tailcall frame for %s on level %d",

gdb.texinfo:5536:control reaches a different line of code at the original stack level
gdb.texinfo:7564:If you need to examine the startup code, or limit the number of levels
in a backtrace, you can change this behavior:
gdb.texinfo:7598:Limit the backtrace to @var{n} levels.  A value of @code{unlimited}
gdb.texinfo:7599:or zero means unlimited levels.
gdb.texinfo:7602:Display the current limit on backtrace levels.

gdb.texinfo:7778:@item frame apply [all | @var{count} | @var{-count} | level @var{level}@dots{}] [@var{flag}]@dots{} @var{command}
   (and 5 other occurences due to the new 'frame apply level')
gdb.texinfo:12510:Stack level 1, frame at 0x7fffffffda30:
gdb.texinfo:27863:The level of the stack frame.  The innermost frame has the level of
gdb.texinfo:29202:   frame=@{level="0",addr="0xffffe410",func="__kernel_vsyscall",
  and a whole bunch of references to level in the mi documentation/examples
  e.g.
gdb.texinfo:29941:For a stack with frame levels 0 through 11:
gdb.texinfo:29977:at the corresponding level.  It is an error if @var{low-frame} is
gdb.texinfo:30009:frame=@{level="0",addr="0x00010734",func="callee4",
gdb.texinfo:30012:frame=@{level="1",addr="0x0001076c",func="callee3",
gdb.texinfo:30015:frame=@{level="2",addr="0x0001078c",func="callee2",
gdb.texinfo:30018:frame=@{level="3",addr="0x000107b4",func="callee1",


The below might  be more clear as 'a low level unique identifier for a frame' ?
frame.h:442:   get_frame_id: A low level frame unique identifier, that consists of

Usages of number
----------------
stack.c:1765:	  /* The argument to apply_ext_lang_frame_filter is the number
stack.c:2750:It can be a stack frame number or the address of the frame."),
stack.c:2796:It can be a stack frame number or the address of the frame."),
cli/cli-cmds.c:1688:The stack is made up of stack frames.  Gdb assigns numbers to stack frames\n\
cli/cli-cmds.c:1693:The commands below can be used to select other frames by number or address."),
mi/mi-cmd-stack.c:76:   specifying the frame numbers at which to start and stop the


The below should be (or are in fact) traceframe number (but some cannot be changed
as they are part of the mi interface).
remote.c:13266:  /* Lookups other than by absolute frame number depend on the current
tracepoint.c:2196:   of information: a frame number, a tracepoint number, and an
tracepoint.c:2200:   target does not give us a frame number or a tracepoint number).
tracepoint.c:2203:   F<hexnum>    (gives the selected frame number)
gdbserver/tracepoint.c:949:   not need to keep a frame number, because they are all sequential
gdbserver/tracepoint.c:951:   always frame number N.  */
mi/mi-main.c:2330:  if (strcmp (mode, "frame-number") == 0)
mi/mi-main.c:2333:	error (_("frame number is required"));

gdb.texinfo:7396:@cindex frame number
@value{GDBN} assigns numbers to all existing stack frames, starting with
and so on upward.  These numbers do not really exist in your program;

**** In the below, the positive number is not a frame number
gdb.texinfo:7447:@itemx @var{n}
Print only the innermost @var{n} frames, where @var{n} is a positive
number.
@item -@var{n}
@itemx -@var{n}
Print only the outermost @var{n} frames, where @var{n} is a positive
number.
gdb.texinfo:7458:with a number to limit the number of frames shown.



gdb.texinfo:7489:Each line in the backtrace shows the frame number and the function name.

*** in the below, this is rather level that is being used ... as otherwise we should
say 'limit the number of numbers' :).
gdb.texinfo:7564:If you need to examine the startup code, or limit the number of levels


gdb.texinfo:7636:Select frame number @var{n}.  Recall that frame zero is the innermost
gdb.texinfo:7666:frame.  The first line shows the frame number, the function name, the

*** also in the below, this is using level (explaining that a level is a number)
gdb.texinfo:7797:levels as @var{level1}-@var{level2}.  The frame level is the number shown


*** the below is really a number, not a 'frame number'
gdb.texinfo:11204:it is the number of frames up in the stack to look.
gdb.texinfo:11231:it is the number of frames up in the stack to look.
gdb.texinfo:11240:it is the number of frames up in the stack to look.
gdb.texinfo:11254:it is the number of frames up in the stack to look.


*** I think the below should be traceframe.
gdb.texinfo:14099:The current trace snapshot (a.k.a.@: @dfn{frame}) number, or -1 if no


*** the below tells that frame level is frame number
@item @var{level}
The frame number, 0 being the topmost frame, i.e., the innermost function.

*** the below should be traceframe number, but that cannot really be changed
as this is part of MI interface.
gdb.texinfo:31858:@item frame-number
*** the below should be traceframe number
gdb.texinfo:39503:The selected frame is number @var{n} in the trace frame buffer;
Joel Brobecker Aug. 21, 2018, 1:10 p.m. UTC | #5
> What I find confusing is to have the same concept
> ('frame something_identifying_a_frame')
> be called sometimes 'frame number' and sometimes 'frame level'.
> 
> My personal preference is to use 'frame level' because:

FWIW, that is my preference as well.
Andrew Burgess Aug. 27, 2018, 11:03 a.m. UTC | #6
Ping!

Eli:

  In this message:
      https://sourceware.org/ml/gdb-patches/2018-07/msg00670.html
  Philippe highlighted that you might have some reservations about
  this patch series, which I think is currently the main blocker for
  this patch getting approval.

  In the thread started here:
      https://sourceware.org/ml/gdb-patches/2018-05/msg00299.html
  and ending here:
      https://sourceware.org/ml/gdb-patches/2018-06/msg00142.html
  you did review and approve one of the original patch variants, which
  is most like the "level" variant of the patch submitted here:
      https://sourceware.org/ml/gdb-patches/2018-08/msg00337.html

  I would be really grateful if you could let me know your current
  thoughts on this patch, are you happy to have the "level" variant
  merged based on your previous approval, or has you position changed?

  Thanks.

Philippe:

  Thanks for the review and feedback in:
      https://sourceware.org/ml/gdb-patches/2018-08/msg00349.html

  I wasn't sure if the second part of you mail was suggesting that
  those instances of level vs number needed to be resolved as part of
  this patch for you to be happy, or if this was just identifying what
  we should clean up if/when this patch is merged.  Additional clarity
  here would help me figure out my next steps for getting this patch
  merged.

  Thanks.

Many thanks to everyone who's taken time to review this for me.

Thanks,
Andrew



* Andrew Burgess <andrew.burgess@embecosm.com> [2018-08-13 23:20:09 +0100]:

> Given a lack of feedback on v4, I've put together two alternative
> versions to pick between...
> 
>   (A) In this version I took onboard the feedback from Eli and
>       Philippe that using "level" might be confusing to users, as
>       "number" is historically what has been used for the integer
>       label we give to frames.
> 
>       The command for selecting a frame by integer is now, 'frame
>       number <NUMBER>' and almost all references to "level" have now
>       been removed from the patch.
> 
>   (B) In this version I've taken onboard the advice from Philippe,
>       identifying places in the patch where I was mixing use of
>       "level" and "number".  I've doubled down on "level" and removed
>       most uses of "number" from the patch.
> 
> If we select patch 'A' then me might want to update 'frame apply level
> ...' to 'frame apply number ...' for consistency.
> 
> If we select patch 'B' then we will probably need a follow up patch
> that goes through the documentation to tighten up references to
> "number" vs "level".
> 
> I really don't mind which approach we take, I guess I'd probably pick
> 'B' over 'A' given we already have 'frame apply level ...' in GDB, but
> if there's preference for 'A' then that's fine.
> 
> I'm also happy to do the follow up patches once we have some agreement
> on which way to go.
> 
> Thanks,
> Andrew
> 
> ---
> 
> Andrew Burgess (1):
>   gdb: Change how frames are selected for 'frame' and 'info frame'.
> 
>  gdb/ChangeLog                               |  36 ++
>  gdb/NEWS                                    |   8 +
>  gdb/cli/cli-decode.c                        |  44 ++-
>  gdb/command.h                               |  14 +
>  gdb/doc/ChangeLog                           |   8 +
>  gdb/doc/gdb.texinfo                         | 108 ++++--
>  gdb/mi/mi-cmd-stack.c                       |   4 +-
>  gdb/stack.c                                 | 535 +++++++++++++++++++---------
>  gdb/stack.h                                 |   2 +-
>  gdb/testsuite/ChangeLog                     |   7 +
>  gdb/testsuite/gdb.base/frame-selection.c    |  52 +++
>  gdb/testsuite/gdb.base/frame-selection.exp  | 157 ++++++++
>  gdb/testsuite/gdb.mi/mi-frame-selection.c   |  34 ++
>  gdb/testsuite/gdb.mi/mi-frame-selection.exp |  89 +++++
>  14 files changed, 896 insertions(+), 202 deletions(-)
>  create mode 100644 gdb/testsuite/gdb.base/frame-selection.c
>  create mode 100644 gdb/testsuite/gdb.base/frame-selection.exp
>  create mode 100644 gdb/testsuite/gdb.mi/mi-frame-selection.c
>  create mode 100644 gdb/testsuite/gdb.mi/mi-frame-selection.exp
> 
> -- 
> 2.14.4
>
Eli Zaretskii Aug. 27, 2018, 3:23 p.m. UTC | #7
> Date: Mon, 27 Aug 2018 12:03:54 +0100
> From: Andrew Burgess <andrew.burgess@embecosm.com>
> Cc: Philippe Waroquiers <philippe.waroquiers@skynet.be>,
> 	Eli Zaretskii <eliz@gnu.org>
> 
> Eli:
> 
>   In this message:
>       https://sourceware.org/ml/gdb-patches/2018-07/msg00670.html
>   Philippe highlighted that you might have some reservations about
>   this patch series, which I think is currently the main blocker for
>   this patch getting approval.
> 
>   In the thread started here:
>       https://sourceware.org/ml/gdb-patches/2018-05/msg00299.html
>   and ending here:
>       https://sourceware.org/ml/gdb-patches/2018-06/msg00142.html
>   you did review and approve one of the original patch variants, which
>   is most like the "level" variant of the patch submitted here:
>       https://sourceware.org/ml/gdb-patches/2018-08/msg00337.html
> 
>   I would be really grateful if you could let me know your current
>   thoughts on this patch, are you happy to have the "level" variant
>   merged based on your previous approval, or has you position changed?

I just said

  I question the wisdom of changing such veteran terminology.

And then:

  If we are going to make this change, then I would suggest to keep the
  index entry, _add_ to it an entry about "frame level", and explain
  here what that level is, something like this:

    @value{GDBN} labels each existing stack frame with a @dfn{level}, a
    number that is zero for the innermost frame, one for the frame that
    called it, and so on upward.  These level numbers give you a way of
    designating stack frames in @value{GDBN} commands.

IOW, I urged us to think whether we really want the change (and
invited others to comment).  Then I had a small suggestion for if we
do make the change.

That is all.  It was never my intention to block the patch, and if my
words were unfortunate enough to be interpreted that way, I apologize.

Thanks.
diff mbox

Patch

diff --git a/gdb/NEWS b/gdb/NEWS
index 2b51465495f..524a3a13913 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -67,6 +67,14 @@  thread apply [all | COUNT | -COUNT] [FLAG]... COMMAND
 * C expressions can now use _Alignof, and C++ expressions can now use
   alignof.
 
+* Changes to the "frame", "select-frame", and "info frame" CLI
+  commands, as well as the "-stack-select-frame" MI command.  These
+  commands all now take a frame specification which is either a frame
+  number, or one of the keywords 'level', 'address', 'function', or
+  'view' followed by a parameter.  Selecting a frame by address, or
+  viewing a frame outside the current backtrace now requires the use
+  of a keyword.  Selecting a frame by number is unchanged.
+
 * New commands
 
 set debug fbsd-nat
diff --git a/gdb/cli/cli-decode.c b/gdb/cli/cli-decode.c
index c8dda700ca8..fb44fc1627f 100644
--- a/gdb/cli/cli-decode.c
+++ b/gdb/cli/cli-decode.c
@@ -251,6 +251,23 @@  add_cmd (const char *name, enum command_class theclass,
   return result;
 }
 
+/* Add an element with a suppress notification to the LIST of commands.  */
+
+struct cmd_list_element *
+add_cmd_suppress_notification (const char *name, enum command_class theclass,
+			       cmd_const_cfunc_ftype *fun, const char *doc,
+			       struct cmd_list_element **list,
+			       int *suppress_notification)
+{
+  struct cmd_list_element *element;
+
+  element = add_cmd (name, theclass, fun, doc, list);
+  element->suppress_notification = suppress_notification;
+
+  return element;
+}
+
+
 /* Deprecates a command CMD.
    REPLACEMENT is the name of the command which should be used in
    place of this command, or NULL if no such command exists.
@@ -362,6 +379,25 @@  add_prefix_cmd (const char *name, enum command_class theclass,
   return c;
 }
 
+/* Like ADD_PREFIX_CMD but sets the suppress_notification pointer on the
+   new command list element.  */
+
+struct cmd_list_element *
+add_prefix_cmd_suppress_notification
+               (const char *name, enum command_class theclass,
+		cmd_const_cfunc_ftype *fun,
+		const char *doc, struct cmd_list_element **prefixlist,
+		const char *prefixname, int allow_unknown,
+		struct cmd_list_element **list,
+		int *suppress_notification)
+{
+  struct cmd_list_element *element
+    = add_prefix_cmd (name, theclass, fun, doc, prefixlist,
+		      prefixname, allow_unknown, list);
+  element->suppress_notification = suppress_notification;
+  return element;
+}
+
 /* Like add_prefix_cmd but sets the abbrev_flag on the new command.  */
 
 struct cmd_list_element *
@@ -893,12 +929,8 @@  add_com_suppress_notification (const char *name, enum command_class theclass,
 			       cmd_const_cfunc_ftype *fun, const char *doc,
 			       int *suppress_notification)
 {
-  struct cmd_list_element *element;
-
-  element = add_cmd (name, theclass, fun, doc, &cmdlist);
-  element->suppress_notification = suppress_notification;
-
-  return element;
+  return add_cmd_suppress_notification (name, theclass, fun, doc,
+					&cmdlist, suppress_notification);
 }
 
 /* Recursively walk the commandlist structures, and print out the
diff --git a/gdb/command.h b/gdb/command.h
index 3dde2475cb1..e3d55c2dcba 100644
--- a/gdb/command.h
+++ b/gdb/command.h
@@ -148,6 +148,12 @@  extern struct cmd_list_element *add_cmd (const char *, enum command_class,
 					 const char *,
 					 struct cmd_list_element **);
 
+extern struct cmd_list_element *add_cmd_suppress_notification
+			(const char *name, enum command_class theclass,
+			 cmd_const_cfunc_ftype *fun, const char *doc,
+			 struct cmd_list_element **list,
+			 int *suppress_notification);
+
 extern struct cmd_list_element *add_alias_cmd (const char *, const char *,
 					       enum command_class, int,
 					       struct cmd_list_element **);
@@ -165,6 +171,14 @@  extern struct cmd_list_element *add_prefix_cmd (const char *, enum command_class
 						const char *, int,
 						struct cmd_list_element **);
 
+extern struct cmd_list_element *add_prefix_cmd_suppress_notification
+			(const char *name, enum command_class theclass,
+			 cmd_const_cfunc_ftype *fun,
+			 const char *doc, struct cmd_list_element **prefixlist,
+			 const char *prefixname, int allow_unknown,
+			 struct cmd_list_element **list,
+			 int *suppress_notification);
+
 extern struct cmd_list_element *add_abbrev_prefix_cmd (const char *,
 						       enum command_class,
 						       cmd_const_cfunc_ftype *fun,
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index b36a39b5b4c..2eb89e11551 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -7631,21 +7631,56 @@ 
 @table @code
 @kindex frame@r{, selecting}
 @kindex f @r{(@code{frame})}
-@item frame @var{n}
-@itemx f @var{n}
-Select frame number @var{n}.  Recall that frame zero is the innermost
-(currently executing) frame, frame one is the frame that called the
-innermost one, and so on.  The highest-numbered frame is the one for
-@code{main}.
+@item frame @r{[} @var{frame-selection-spec} @r{]}
+@item f @r{[} @var{frame-selection-spec} @r{]}
+The @command{frame} command allows different stack frames to be
+selected.  The @var{frame-selection-spec} can be any of the following:
+
+@table @code
+@kindex frame level
+@item @var{num}
+@item level @var{num}
+Select frame number @var{num}.  Recall that frame zero is the
+innermost (currently executing) frame, frame one is the frame that
+called the innermost one, and so on.  The highest-numbered frame is
+the one for @code{main}.
+
+As this is the most common method of navigating the frame stack then
+the string @command{level} can be dropped, the following two commands
+are equivalent:
+
+@smallexample
+(@value{GDBP}) frame 3
+(@value{GDBP}) frame level 3
+@end smallexample
 
-@item frame @var{stack-addr} [ @var{pc-addr} ]
-@itemx f @var{stack-addr} [ @var{pc-addr} ]
-Select the frame at address @var{stack-addr}.  This is useful mainly if the
-chaining of stack frames has been damaged by a bug, making it
-impossible for @value{GDBN} to assign numbers properly to all frames.  In
-addition, this can be useful when your program has multiple stacks and
-switches between them.  The optional @var{pc-addr} can also be given to
-specify the value of PC for the stack frame.
+@kindex frame address
+@item address @var{stack-address}
+Select the frame with stack address @var{stack-address}.
+
+@kindex frame function
+@item function @var{function-name}
+Select the stack frame for function @var{function-name}.  If there are
+multiple stack frames for function @var{function-name} then the inner
+most stack frame is selected.
+
+@kindex frame view
+@item view @var{stack-address} @r{[} @var{pc-addr} @r{]}
+View a frame that is not part of @value{GDBN}'s backtrace.  The frame
+viewed has stack address @var{stack-addr}, and optionally, a program
+counter address of @var{pc-addr}.
+
+This is useful mainly if the chaining of stack frames has been
+damaged by a bug, making it impossible for @value{GDBN} to assign
+numbers properly to all frames.  In addition, this can be useful
+when your program has multiple stacks and switches between them.
+
+When viewing a frame outside the current backtrace using
+@command{frame view} then you can always return to the original
+stack using one of the previous stack frame selection instructions,
+for example @command{frame level 0}.
+
+@end table
 
 @kindex up
 @item up @var{n}
@@ -7688,11 +7723,13 @@ 
 
 @table @code
 @kindex select-frame
-@item select-frame
+@item select-frame @r{[} @var{frame-selection-spec} @r{]}
 The @code{select-frame} command is a variant of @code{frame} that does
 not display the new frame after selecting it.  This command is
 intended primarily for use in @value{GDBN} command scripts, where the
-output might be unnecessary and distracting.
+output might be unnecessary and distracting.  The
+@var{frame-selection-spec} is as for the @command{frame} command
+described in @ref{Selection, ,Selecting a Frame}.
 
 @kindex down-silently
 @kindex up-silently
@@ -7750,13 +7787,12 @@ 
 something has gone wrong that has made the stack format fail to fit
 the usual conventions.
 
-@item info frame @var{addr}
-@itemx info f @var{addr}
-Print a verbose description of the frame at address @var{addr}, without
-selecting that frame.  The selected frame remains unchanged by this
-command.  This requires the same kind of address (more than one for some
-architectures) that you specify in the @code{frame} command.
-@xref{Selection, ,Selecting a Frame}.
+@item info frame @r{[} @var{frame-selection-spec} @r{]}
+@itemx info f @r{[} @var{frame-selection-spec} @r{]}
+Print a verbose description of the frame selected by
+@var{frame-selection-spec}.  The @var{frame-selection-spec} is the
+same as for the @command{frame} command (@pxref{Selection, ,Selecting
+a Frame}).  The selected frame remains unchanged by this command.
 
 @kindex info args
 @item info args
@@ -30252,11 +30288,12 @@ 
 @subsubheading Synopsis
 
 @smallexample
- -stack-select-frame @var{framenum}
+ -stack-select-frame @var{frame-selection-spec}
 @end smallexample
 
-Change the selected frame.  Select a different frame @var{framenum} on
-the stack.
+Change the selected frame, the @var{frame-selection-spec} is as for
+the @command{frame} command described in @ref{Selection, ,Selecting a
+Frame}.
 
 This command in deprecated in favor of passing the @samp{--frame}
 option to every command.
diff --git a/gdb/mi/mi-cmd-stack.c b/gdb/mi/mi-cmd-stack.c
index 52660bdd498..33ac7663ba8 100644
--- a/gdb/mi/mi-cmd-stack.c
+++ b/gdb/mi/mi-cmd-stack.c
@@ -681,10 +681,8 @@  list_args_or_locals (enum what_to_list what, enum print_values values,
 void
 mi_cmd_stack_select_frame (const char *command, char **argv, int argc)
 {
-  if (argc == 0 || argc > 1)
+  if (!select_frame_from_spec (argv, argc, 0))
     error (_("-stack-select-frame: Usage: FRAME_SPEC"));
-
-  select_frame_command (argv[0], 1 /* not used */ );
 }
 
 void
diff --git a/gdb/stack.c b/gdb/stack.c
index e51c689f437..e32b3efa245 100644
--- a/gdb/stack.c
+++ b/gdb/stack.c
@@ -102,6 +102,9 @@  static void set_last_displayed_sal (int valid,
 				    struct symtab *symtab,
 				    int line);
 
+static struct frame_info *find_frame_for_function (const char *);
+static struct frame_info *find_frame_for_address (CORE_ADDR);
+
 /* Zero means do things normally; we are interacting directly with the
    user.  One means print the full filename and linenumber when a
    frame is printed, and do so in a format emacs18/emacs19.22 can
@@ -1255,134 +1258,34 @@  print_frame (struct frame_info *frame, int print_level,
 }
 
 
-/* Read a frame specification in whatever the appropriate format is from
-   FRAME_EXP.  Call error() if the specification is in any way invalid (so
-   this function never returns NULL).  When SELECTED_FRAME_P is non-NULL
-   set its target to indicate that the default selected frame was used.  */
+/* Completion function for "frame function", "info frame function", and
+   "select-frame function" commands.  */
 
-static struct frame_info *
-parse_frame_specification (const char *frame_exp, int *selected_frame_p)
+void
+frame_selection_by_function_completer (struct cmd_list_element *ignore,
+				       completion_tracker &tracker,
+				       const char *text, const char *word)
 {
-  int numargs;
-  struct value *args[4];
-  CORE_ADDR addrs[ARRAY_SIZE (args)];
-
-  if (frame_exp == NULL)
-    numargs = 0;
-  else
-    {
-      numargs = 0;
-      while (1)
-	{
-	  const char *p;
-
-	  /* Skip leading white space, bail of EOL.  */
-	  frame_exp = skip_spaces (frame_exp);
-	  if (!*frame_exp)
-	    break;
-
-	  /* Parse the argument, extract it, save it.  */
-	  for (p = frame_exp;
-	       *p && !ISSPACE (*p);
-	       p++);
-	  std::string addr_string (frame_exp, p - frame_exp);
-	  frame_exp = p;
-	  
-	  /* NOTE: Parse and evaluate expression, but do not use
-	     functions such as parse_and_eval_long or
-	     parse_and_eval_address to also extract the value.
-	     Instead value_as_long and value_as_address are used.
-	     This avoids problems with expressions that contain
-	     side-effects.  */
-	  if (numargs >= ARRAY_SIZE (args))
-	    error (_("Too many args in frame specification"));
-	  args[numargs++] = parse_and_eval (addr_string.c_str ());
-	}
-    }
-
-  /* If no args, default to the selected frame.  */
-  if (numargs == 0)
-    {
-      if (selected_frame_p != NULL)
-	(*selected_frame_p) = 1;
-      return get_selected_frame (_("No stack."));
-    }
-
-  /* None of the remaining use the selected frame.  */
-  if (selected_frame_p != NULL)
-    (*selected_frame_p) = 0;
-
-  /* Assume the single arg[0] is an integer, and try using that to
-     select a frame relative to current.  */
-  if (numargs == 1)
-    {
-      struct frame_info *fid;
-      int level = value_as_long (args[0]);
-
-      fid = find_relative_frame (get_current_frame (), &level);
-      if (level == 0)
-	/* find_relative_frame was successful.  */
-	return fid;
-    }
-
-  /* Convert each value into a corresponding address.  */
-  {
-    int i;
-
-    for (i = 0; i < numargs; i++)
-      addrs[i] = value_as_address (args[i]);
-  }
-
-  /* Assume that the single arg[0] is an address, use that to identify
-     a frame with a matching ID.  Should this also accept stack/pc or
-     stack/pc/special.  */
-  if (numargs == 1)
-    {
-      struct frame_id id = frame_id_build_wild (addrs[0]);
-      struct frame_info *fid;
-
-      /* If (s)he specifies the frame with an address, he deserves
-	 what (s)he gets.  Still, give the highest one that matches.
-	 (NOTE: cagney/2004-10-29: Why highest, or outer-most, I don't
-	 know).  */
-      for (fid = get_current_frame ();
-	   fid != NULL;
-	   fid = get_prev_frame (fid))
-	{
-	  if (frame_id_eq (id, get_frame_id (fid)))
-	    {
-	      struct frame_info *prev_frame;
-
-	      while (1)
-		{
-		  prev_frame = get_prev_frame (fid);
-		  if (!prev_frame
-		      || !frame_id_eq (id, get_frame_id (prev_frame)))
-		    break;
-		  fid = prev_frame;
-		}
-	      return fid;
-	    }
-	}
-      }
-
-  /* We couldn't identify the frame as an existing frame, but
-     perhaps we can create one with a single argument.  */
-  if (numargs == 1)
-    return create_new_frame (addrs[0], 0);
-  else if (numargs == 2)
-    return create_new_frame (addrs[0], addrs[1]);
-  else
-    error (_("Too many args in frame specification"));
+  /* This is used to complete function names within a stack.  It would be
+     nice if instead of offering all available function names, we only
+     offered functions that were actually in the stack.  However, this
+     would probably mean unwinding the stack to completion, which could
+     take too long (or on a corrupted stack, possibly not end).  For now I
+     offer all symbol names as a safer choice.  */
+  collect_symbol_completion_matches (tracker,
+				     complete_symbol_mode::EXPRESSION,
+				     symbol_name_match_type::EXPRESSION,
+				     text, word);
 }
 
-/* Print verbosely the selected frame or the frame at address
-   ADDR_EXP.  Absolutely all information in the frame is printed.  */
+/* Core of all the "info frame" sub-commands.  Print verbosely the frame FI
+   if SELECTED_FRAME_P is true then frame FI is the current frame, which
+   was selected as a default due to the user not providing any arguments
+   to select some other frame.  */
 
 static void
-info_frame_command (const char *addr_exp, int from_tty)
+info_frame_command_core (struct frame_info *fi, bool selected_frame_p)
 {
-  struct frame_info *fi;
   struct symbol *func;
   struct symtab *s;
   struct frame_info *calling_frame_info;
@@ -1390,7 +1293,6 @@  info_frame_command (const char *addr_exp, int from_tty)
   const char *funname = 0;
   enum language funlang = language_unknown;
   const char *pc_regname;
-  int selected_frame_p;
   struct gdbarch *gdbarch;
   CORE_ADDR frame_pc;
   int frame_pc_p;
@@ -1398,7 +1300,6 @@  info_frame_command (const char *addr_exp, int from_tty)
   CORE_ADDR caller_pc = 0;
   int caller_pc_p = 0;
 
-  fi = parse_frame_specification (addr_exp, &selected_frame_p);
   gdbarch = get_frame_arch (fi);
 
   /* Name of the value returned by get_frame_pc().  Per comments, "pc"
@@ -1739,6 +1640,140 @@  trailing_outermost_frame (int count)
   return trailing;
 }
 
+/* The core of all the "select-frame" sub-commands.  Just wraps a call to
+   SELECT_FRAME.  */
+
+static void
+select_frame_command_core (struct frame_info *fi, bool ignored)
+{
+  struct frame_info *prev_frame = get_selected_frame_if_set ();
+  select_frame (fi);
+  if (get_selected_frame_if_set () != prev_frame)
+    gdb::observers::user_selected_context_changed.notify (USER_SELECTED_FRAME);
+}
+
+/* The core of all the "frame" sub-commands.  Select frame FI, and if this
+   means we change frame send out a change notification (otherwise, just
+   reprint the current frame summary).   */
+
+static void
+frame_command_core (struct frame_info *fi, bool ignored)
+{
+  struct frame_info *prev_frame = get_selected_frame_if_set ();
+
+  select_frame (fi);
+  if (get_selected_frame_if_set () != prev_frame)
+    gdb::observers::user_selected_context_changed.notify (USER_SELECTED_FRAME);
+  else
+    print_selected_thread_frame (current_uiout, USER_SELECTED_FRAME);
+}
+
+/* The three commands 'frame', 'select-frame', and 'info frame' all have a
+   common set of sub-commands that allow a specific frame to be selected.
+   All of the sub-command functions are static methods within this class
+   template which is then instantiated below.  */
+
+template <void (*FPTR) (struct frame_info *, bool)>
+class frame_command_helper
+{
+public:
+
+  /* The "frame level" family of commands.  The ARG is a number that is
+     the frame's level in the stack.  */
+  static void
+  level (const char *arg, int from_tty)
+  {
+    int level = value_as_long (parse_and_eval (arg));
+    struct frame_info *fid
+      = find_relative_frame (get_current_frame (), &level);
+    if (level != 0)
+      error (_("No frame at level %s."), arg);
+    FPTR (fid, false);
+  }
+
+  /* The "frame address" family of commands.  ARG is a stack-pointer
+     address for an existing frame.  This command does not allow new
+     frames to be created.  */
+
+  static void
+  address (const char *arg, int from_tty)
+  {
+    CORE_ADDR addr = value_as_address (parse_and_eval (arg));
+    struct frame_info *fid = find_frame_for_address (addr);
+    if (fid == NULL)
+      error (_("No frame at address %s."), arg);
+    FPTR (fid, false);
+  }
+
+  /* The "frame view" family of commands.  ARG is one or two addresses and
+     is used to view a frame that might be outside the current backtrace.
+     The addresses are stack-pointer address, and (optional) pc-address.  */
+
+  static void
+  view (const char *args, int from_tty)
+  {
+    struct frame_info *fid;
+
+    if (args == NULL)
+    error (_("Missing address argument to view a frame"));
+
+    gdb_argv argv (args);
+
+    if (argv.count () == 2)
+      {
+	CORE_ADDR addr[2];
+
+	addr [0] = value_as_address (parse_and_eval (argv[0]));
+	addr [1] = value_as_address (parse_and_eval (argv[1]));
+	fid = create_new_frame (addr[0], addr[1]);
+      }
+    else
+      {
+	CORE_ADDR addr = value_as_address (parse_and_eval (argv[0]));
+	fid = create_new_frame (addr, false);
+      }
+    FPTR (fid, false);
+  }
+
+  /* The "frame function" family of commands.  ARG is the name of a
+     function within the stack, the first function (searching from frame
+     0) with that name will be selected.  */
+
+  static void
+  function (const char *arg, int from_tty)
+  {
+    if (arg == NULL)
+      error (_("Missing function name argument"));
+    struct frame_info *fid = find_frame_for_function (arg);
+    if (fid == NULL)
+      error (_("No frame for function \"%s\"."), arg);
+    FPTR (fid, false);
+  }
+
+  /* The "frame" base command, that is, when no sub-command is specified.
+     If one argument is provided then we assume that this is a frame level
+     number as historically, this was the supported command syntax that was
+     used most often.
+
+     If no argument is provided, then the current frame is selected.  */
+
+  static void
+  base_command (const char *arg, int from_tty)
+  {
+    if (arg == NULL)
+      FPTR (get_selected_frame (_("No stack.")), true);
+    else
+      level (arg, from_tty);
+  }
+};
+
+/* Instantiate three FRAME_COMMAND_HELPER instances to implement the
+   sub-commands for 'info frame', 'frame', and 'select-frame' commands.  */
+
+static frame_command_helper <info_frame_command_core> info_frame_cmd;
+static frame_command_helper <frame_command_core> frame_cmd;
+static frame_command_helper <select_frame_command_core> select_frame_cmd;
+
 /* Print briefly all stack frames or just the innermost COUNT_EXP
    frames.  */
 
@@ -2227,37 +2262,43 @@  find_relative_frame (struct frame_info *frame, int *level_offset_ptr)
   return frame;
 }
 
-/* The "select_frame" command.  With no argument this is a NOP.
-   Select the frame at level LEVEL_EXP if it is a valid level.
-   Otherwise, treat LEVEL_EXP as an address expression and select it.
-
-   See parse_frame_specification for more info on proper frame
-   expressions.  */
-
-void
-select_frame_command (const char *level_exp, int from_tty)
-{
-  struct frame_info *prev_frame = get_selected_frame_if_set ();
-
-  select_frame (parse_frame_specification (level_exp, NULL));
-  if (get_selected_frame_if_set () != prev_frame)
-    gdb::observers::user_selected_context_changed.notify (USER_SELECTED_FRAME);
-}
-
-/* The "frame" command.  With no argument, print the selected frame
-   briefly.  With an argument, behave like select_frame and then print
-   the selected frame.  */
+/* Select a frame using ARGV.  This is used from the MI -stack-select-frame
+   to provide the same frame specification mechanism that the CLI has for
+   commands like 'frame'.  The return value is true if the contents of
+   ARGV looked like a sensible attempt to change the frame (an error might
+   still be thrown though), or false if the contents of ARGV are not a
+   correct frame specification.  */
 
-static void
-frame_command (const char *level_exp, int from_tty)
+bool
+select_frame_from_spec (char **argv, int argc, int from_tty)
 {
-  struct frame_info *prev_frame = get_selected_frame_if_set ();
+  if (argc == 1)
+    select_frame_cmd.level (argv[0], from_tty);
+  else if (argc == 2
+	   && strncasecmp ("level", argv[0], strlen (argv[0])) == 0)
+    select_frame_cmd.level (argv[1], from_tty);
+  else if (argc == 2
+	   && strncasecmp ("address", argv[0], strlen (argv[0])) == 0)
+    select_frame_cmd.address (argv[1], from_tty);
+  else if (argc == 2
+	   && strncasecmp ("function", argv[0], strlen (argv[0])) == 0)
+    select_frame_cmd.function (argv[1], from_tty);
+  else if ((argc == 2 || argc == 3)
+	   && strncasecmp ("view", argv[0], strlen (argv[0])) == 0)
+    {
+      std::string arg;
+
+      if (argc == 2)
+	arg = string_printf ("%s", argv[1]);
+      else
+	arg = string_printf ("%s %s", argv[1], argv[2]);
 
-  select_frame (parse_frame_specification (level_exp, NULL));
-  if (get_selected_frame_if_set () != prev_frame)
-    gdb::observers::user_selected_context_changed.notify (USER_SELECTED_FRAME);
+      select_frame_cmd.view (arg.c_str (), from_tty);
+    }
   else
-    print_selected_thread_frame (current_uiout, USER_SELECTED_FRAME);
+    return false;
+
+  return true;
 }
 
 /* Select the frame up one or COUNT_EXP stack levels from the
@@ -2712,13 +2753,61 @@  faas_command (const char *cmd, int from_tty)
 }
 
 
+/* Find inner-mode frame with frame address ADDRESS.  Return NULL if no
+   matching frame can be found.  */
+
+static struct frame_info *
+find_frame_for_address (CORE_ADDR address)
+{
+  struct frame_id id;
+  struct frame_info *fid;
+
+  id = frame_id_build_wild (address);
+
+  /* If (s)he specifies the frame with an address, he deserves
+     what (s)he gets.  Still, give the highest one that matches.
+     (NOTE: cagney/2004-10-29: Why highest, or outer-most, I don't
+     know).  */
+  for (fid = get_current_frame ();
+       fid != NULL;
+       fid = get_prev_frame (fid))
+    {
+      if (frame_id_eq (id, get_frame_id (fid)))
+	{
+	  struct frame_info *prev_frame;
+
+	  while (1)
+	    {
+	      prev_frame = get_prev_frame (fid);
+	      if (!prev_frame
+		  || !frame_id_eq (id, get_frame_id (prev_frame)))
+		break;
+	      fid = prev_frame;
+	    }
+	  return fid;
+	}
+    }
+  return NULL;
+}
+
+
+
+/* Commands with a prefix of `frame apply'.  */
+static struct cmd_list_element *frame_apply_cmd_list = NULL;
+
 /* Commands with a prefix of `frame'.  */
-struct cmd_list_element *frame_cmd_list = NULL;
+static struct cmd_list_element *frame_cmd_list = NULL;
+
+/* Commands with a prefix of `select frame'.  */
+static struct cmd_list_element *select_frame_cmd_list = NULL;
+
+/* Commands with a prefix of `info frame'.  */
+static struct cmd_list_element *info_frame_cmd_list = NULL;
 
 void
 _initialize_stack (void)
 {
-  static struct cmd_list_element *frame_apply_list = NULL;
+  struct cmd_list_element *cmd;
 
   add_com ("return", class_stack, return_command, _("\
 Make selected stack frame return to its caller.\n\
@@ -2742,12 +2831,12 @@  An argument says how many frames down to go."));
 Same as the `down' command, but does not print anything.\n\
 This is useful in command scripts."));
 
-  add_prefix_cmd ("frame", class_stack, frame_command, _("\
-Select and print a stack frame.\nWith no argument, \
-print the selected stack frame.  (See also \"info frame\").\n\
-An argument specifies the frame to select.\n\
-It can be a stack frame number or the address of the frame."),
-		  &frame_cmd_list, "frame ", 1, &cmdlist);
+  add_prefix_cmd ("frame", class_stack,
+                  &frame_cmd.base_command, _("\
+Select and print a stack frame.\n\
+With no argument, print the selected stack frame.  (See also \"info frame\").\n\
+A single numerical argument specifies the frame to select."),
+                  &frame_cmd_list, "frame ", 1, &cmdlist);
 
   add_com_alias ("f", "frame", class_stack, 1);
 
@@ -2765,7 +2854,7 @@  or produces no output."
 Usage: frame apply COUNT [FLAG]... COMMAND\n\
 With a negative COUNT argument, applies the command on outermost -COUNT frames.\n"
 FRAME_APPLY_FLAGS_HELP),
-		  &frame_apply_list, "frame apply ", 1, &frame_cmd_list);
+		  &frame_apply_cmd_list, "frame apply ", 1, &frame_cmd_list);
 
   add_cmd ("all", class_stack, frame_apply_all_command,
 	   _("\
@@ -2773,7 +2862,7 @@  Apply a command to all frames.\n\
 \n\
 Usage: frame apply all [FLAG]... COMMAND\n"
 FRAME_APPLY_FLAGS_HELP),
-	   &frame_apply_list);
+	   &frame_apply_cmd_list);
 
   add_cmd ("level", class_stack, frame_apply_level_command,
 	   _("\
@@ -2782,19 +2871,97 @@  Apply a command to a list of frames.\n\
 Usage: frame apply level LEVEL... [FLAG]... COMMAND\n\
 ID is a space-separated list of LEVELs of frames to apply COMMAND on.\n"
 FRAME_APPLY_FLAGS_HELP),
-	   &frame_apply_list);
+	   &frame_apply_cmd_list);
 
   add_com ("faas", class_stack, faas_command, _("\
 Apply a command to all frames (ignoring errors and empty output).\n\
 Usage: faas COMMAND\n\
 shortcut for 'frame apply all -s COMMAND'"));
 
-  add_com_suppress_notification ("select-frame", class_stack, select_frame_command, _("\
+
+  add_prefix_cmd ("frame", class_stack,
+		  &frame_cmd.base_command, _("\
+Select and print a stack frame.\n\
+With no argument, print the selected stack frame.  (See also \"info frame\").\n\
+A single numerical argument specifies the frame to select."),
+		  &frame_cmd_list, "frame ", 1, &cmdlist);
+  add_com_alias ("f", "frame", class_stack, 1);
+
+  add_cmd ("address", class_stack, &frame_cmd.address,
+	   _("\
+Select and print a stack frame by stack address\n\
+\n\
+Usage: frame address STACK-ADDRESS"),
+	   &frame_cmd_list);
+
+  add_cmd ("view", class_stack, &frame_cmd.view,
+	   _("\
+View a stack frame that might be outside the current backtrace.\n\
+\n\
+Usage: frame view STACK-ADDRESS\n\
+       frame view STACK-ADDRESS PC-ADDRESS"),
+	   &frame_cmd_list);
+
+  cmd = add_cmd ("function", class_stack, &frame_cmd.function,
+	   _("\
+Select and print a stack frame by function name.\n\
+\n\
+Usage: frame function NAME\n\
+\n\
+The innermost frame that visited function NAME is selected."),
+	   &frame_cmd_list);
+  set_cmd_completer (cmd, frame_selection_by_function_completer);
+
+
+  add_cmd ("level", class_stack, &frame_cmd.level,
+	   _("\
+Select and print a stack frame by level.\n\
+\n\
+Usage: frame level NUMBER"),
+	   &frame_cmd_list);
+
+  cmd = add_prefix_cmd_suppress_notification ("select-frame", class_stack,
+		      &select_frame_cmd.base_command, _("\
 Select a stack frame without printing anything.\n\
-An argument specifies the frame to select.\n\
-It can be a stack frame number or the address of the frame."),
+A single numerical argument specifies the frame to select."),
+		      &select_frame_cmd_list, "select-frame ", 1, &cmdlist,
+		      &cli_suppress_notification.user_selected_context);
+
+  add_cmd_suppress_notification ("address", class_stack,
+			 &select_frame_cmd.address, _("\
+Select a stack frame by stack address.\n\
+\n\
+Usage: select-frame address STACK-ADDRESS"),
+			 &select_frame_cmd_list,
+			 &cli_suppress_notification.user_selected_context);
+
+
+  add_cmd_suppress_notification ("view", class_stack,
+		 &select_frame_cmd.view, _("\
+Select a stack frame that might be outside the current backtrace.\n\
+\n\
+Usage: select-frame view STACK-ADDRESS\n\
+       select-frame view STACK-ADDRESS PC-ADDRESS"),
+		 &select_frame_cmd_list,
 		 &cli_suppress_notification.user_selected_context);
 
+  cmd = add_cmd_suppress_notification ("function", class_stack,
+	       &select_frame_cmd.function, _("\
+Select a stack frame by function name.\n\
+\n\
+Usage: select-frame function NAME"),
+	       &select_frame_cmd_list,
+	       &cli_suppress_notification.user_selected_context);
+  set_cmd_completer (cmd, frame_selection_by_function_completer);
+
+  add_cmd_suppress_notification ("level", class_stack,
+			 &select_frame_cmd.level, _("\
+Select a stack frame by level.\n\
+\n\
+Usage: select-frame level NUMBER"),
+			 &select_frame_cmd_list,
+			 &cli_suppress_notification.user_selected_context);
+
   add_com ("backtrace", class_stack, backtrace_command, _("\
 Print backtrace of all stack frames, or innermost COUNT frames.\n\
 Usage: backtrace [QUALIFIERS]... [COUNT]\n\
@@ -2808,9 +2975,45 @@  on this backtrace."));
   add_info ("stack", backtrace_command,
 	    _("Backtrace of the stack, or innermost COUNT frames."));
   add_info_alias ("s", "stack", 1);
-  add_info ("frame", info_frame_command,
-	    _("All about selected stack frame, or frame at ADDR."));
+
+  add_prefix_cmd ("frame", class_info, &info_frame_cmd.base_command,
+		  _("All about the selected stack frame.\n\
+With no arguments, displays information about the currently selected stack\n\
+frame.  Alternatively a frame specification may be provided (See \"frame\")\n\
+the information is then printed about the specified frame."),
+		  &info_frame_cmd_list, "info frame ", 1, &infolist);
   add_info_alias ("f", "frame", 1);
+
+  add_cmd ("address", class_stack, &info_frame_cmd.address,
+	   _("\
+Print information about a stack frame selected by stack address.\n\
+\n\
+Usage: info frame address STACK-ADDRESS"),
+	   &info_frame_cmd_list);
+
+  add_cmd ("view", class_stack, &info_frame_cmd.view,
+	   _("\
+Print information about a stack frame outside the current backtrace.\n\
+\n\
+Usage: info frame view STACK-ADDRESS\n\
+       info frame view STACK-ADDRESS PC-ADDRESS"),
+	   &info_frame_cmd_list);
+
+  cmd = add_cmd ("function", class_stack, &info_frame_cmd.function,
+	   _("\
+Print information about a stack frame selected by function name.\n\
+\n\
+Usage: info frame function NAME"),
+	   &info_frame_cmd_list);
+  set_cmd_completer (cmd, frame_selection_by_function_completer);
+
+  add_cmd ("level", class_stack, &info_frame_cmd.level,
+	   _("\
+Print information about a stack frame selected by level.\n\
+\n\
+Usage: info frame level NUMBER"),
+	   &info_frame_cmd_list);
+
   add_info ("locals", info_locals_command,
 	    _("Local variables of current stack frame."));
   add_info ("args", info_args_command,
diff --git a/gdb/stack.h b/gdb/stack.h
index ca190efa9c3..29794872d70 100644
--- a/gdb/stack.h
+++ b/gdb/stack.h
@@ -20,7 +20,7 @@ 
 #ifndef STACK_H
 #define STACK_H
 
-void select_frame_command (const char *level_exp, int from_tty);
+bool select_frame_from_spec (char **argv, int argc, int from_tty);
 
 gdb::unique_xmalloc_ptr<char> find_frame_funname (struct frame_info *frame,
 						  enum language *funlang,
diff --git a/gdb/testsuite/gdb.base/frame-selection.c b/gdb/testsuite/gdb.base/frame-selection.c
new file mode 100644
index 00000000000..f3d81f223e0
--- /dev/null
+++ b/gdb/testsuite/gdb.base/frame-selection.c
@@ -0,0 +1,52 @@ 
+/* Copyright 2018 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+int
+frame_2 (void)
+{
+  return 0;
+}
+
+int
+frame_1 (void)
+{
+  return frame_2 ();
+}
+
+int
+recursive (int arg)
+{
+  int v;
+
+  if (arg < 2)
+    v = recursive (arg + 1);
+  else
+    v = frame_2 ();
+
+  return v;
+}
+
+int
+main (void)
+{
+  int i, j;
+
+  i = frame_1 ();
+  j = recursive (0);
+
+  return i + j;
+}
diff --git a/gdb/testsuite/gdb.base/frame-selection.exp b/gdb/testsuite/gdb.base/frame-selection.exp
new file mode 100644
index 00000000000..3bfcf7b47aa
--- /dev/null
+++ b/gdb/testsuite/gdb.base/frame-selection.exp
@@ -0,0 +1,157 @@ 
+# Copyright 2018 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+standard_testfile
+
+if {[prepare_for_testing "failed to prepare" $testfile $srcfile {debug}]} {
+    return -1
+}
+
+runto_main
+gdb_breakpoint frame_2
+gdb_continue_to_breakpoint frame_2
+
+gdb_test "bt" "#0  frame_2.*#1  $hex in frame_1.*#2  $hex in main.*" "backtrace at breakpoint"
+
+# Perform "info frame" to extract the frames address.
+proc get_frame_address { {testname ""} } {
+    global hex gdb_prompt
+
+    set testname "get_frame_address: ${testname}"
+    set frame_address "unknown"
+
+    send_gdb "info frame\n"
+    gdb_expect {
+	-re ", frame at ($hex):\r\n.*\r\n$gdb_prompt $" {
+	    set frame_address $expect_out(1,string)
+	    pass $testname
+	}
+	-re ".*$gdb_prompt $" { fail $testname }
+	timeout { fail "$testname (timeout)" }
+    }
+
+    return $frame_address
+}
+
+# Passes a list of addresses.  Return a new address that is not in the
+# list.
+proc get_new_address { {addresses {}} } {
+    return [format "%#x" [expr [lindex $addresses [llength addresses]] + 0x10 ]]
+}
+
+proc check_frame { level address function } {
+    global hex gdb_prompt
+
+    set testname "check frame level ${level}"
+    send_gdb "info frame\n"
+    gdb_expect {
+	-re "Stack level ${level}, frame at ($address):\r\n rip = $hex in ${function} \(\[^\r\n\]*\); saved rip = $hex\r\n.*\r\n$gdb_prompt $" {
+	    pass $testname
+	}
+	-re ".*$gdb_prompt $" { fail $testname }
+	timeout { fail "$testname (timeout)" }
+    }
+}
+
+# Select frame using level number, but relying on this being the
+# default action, so "frame 0" performs "frame level 0".
+gdb_test "frame 0" "#0  frame_2.*"
+set frame_0_address [ get_frame_address "frame 0" ]
+gdb_test "frame 1" "#1  $hex in frame_1.*"
+set frame_1_address [ get_frame_address "frame 1" ]
+gdb_test "frame 2" "#2  $hex in main.*"
+set frame_2_address [ get_frame_address "frame 2" ]
+gdb_test "frame 3" "No frame at level 3\."
+
+# Find an address that matches no frame
+set no_frame_address [ get_new_address [list $frame_0_address \
+					     $frame_1_address \
+					     $frame_2_address] ]
+
+# Select frame using 'level' specification.
+gdb_test "frame level 0" "#0  frame_2.*"
+gdb_test "frame level 1" "#1  $hex in frame_1.*"
+gdb_test "frame level 2" "#2  $hex in main.*"
+gdb_test "frame level 3" "No frame at level 3\."
+
+# Select frame by address.
+gdb_test "frame address ${frame_0_address}" "#0  frame_2.*"
+gdb_test "frame address ${frame_1_address}" "#1  $hex in frame_1.*"
+gdb_test "frame address ${frame_2_address}" "#2  $hex in main.*"
+gdb_test "frame address ${no_frame_address}" \
+    "No frame at address ${no_frame_address}\."
+
+# Select frame by function.
+gdb_test "frame function frame_2" "#0  frame_2.*"
+gdb_test "frame function frame_1" "#1  $hex in frame_1.*"
+gdb_test "frame function main" "#2  $hex in main.*"
+# Check for a distinction between a known function not in the stack
+# trace, and an unknown function.
+gdb_test "frame function recursive" "No frame for function \"recursive\"."
+gdb_test "frame function foo" "Function \"foo\" not defined."
+
+
+gdb_test_no_output "select-frame 0"
+check_frame "0" "${frame_0_address}" "frame_2"
+gdb_test_no_output "select-frame 1"
+check_frame "1" "${frame_1_address}" "frame_1"
+gdb_test_no_output "select-frame 2"
+check_frame "2" "${frame_2_address}" "main"
+gdb_test "select-frame 3" "No frame at level 3\."
+
+gdb_test_no_output "select-frame level 0"
+check_frame "0" "${frame_0_address}" "frame_2"
+gdb_test_no_output "select-frame level 1"
+check_frame "1" "${frame_1_address}" "frame_1"
+gdb_test_no_output "select-frame level 2"
+check_frame "2" "${frame_2_address}" "main"
+gdb_test "select-frame level 3" "No frame at level 3\."
+
+gdb_test_no_output "select-frame address ${frame_0_address}"
+check_frame "0" "${frame_0_address}" "frame_2"
+gdb_test_no_output "select-frame address ${frame_1_address}"
+check_frame "1" "${frame_1_address}" "frame_1"
+gdb_test_no_output "select-frame address ${frame_2_address}"
+check_frame "2" "${frame_2_address}" "main"
+gdb_test "select-frame address ${no_frame_address}" \
+    "No frame at address ${no_frame_address}\."
+
+gdb_test_no_output "select-frame function frame_2"
+check_frame "0" "${frame_0_address}" "frame_2"
+gdb_test_no_output "select-frame function frame_1"
+check_frame "1" "${frame_1_address}" "frame_1"
+gdb_test_no_output "select-frame function main"
+check_frame "2" "${frame_2_address}" "main"
+# Check for a distinction between a known function not in the stack
+# trace, and an unknown function.
+gdb_test "select-frame function recursive" \
+    "No frame for function \"recursive\"."
+gdb_test "select-frame function foo" \
+    "Function \"foo\" not defined."
+
+# Now continue until we hit the breakpoint again.
+gdb_continue_to_breakpoint frame_2
+gdb_test "bt" \
+    "#0  frame_2.*#1  $hex in recursive.*#2  $hex in recursive.*#3  $hex in recursive.*#4  $hex in main.*" \
+    "backtrace at breakpoint with recursive frames"
+
+# Check "frame function" when a function name occurs multiple times in
+# the stack.  The inner most (lowest level number) should always be
+# selected.
+gdb_test "frame function frame_2" "#0  frame_2.*"
+gdb_test "frame function recursive" "#1  $hex in recursive.*"
+gdb_test "frame function recursive" "#1  $hex in recursive.*"
+gdb_test "frame function main" "#4  $hex in main.*"
+gdb_test "frame function recursive" "#1  $hex in recursive.*"
diff --git a/gdb/testsuite/gdb.mi/mi-frame-selection.c b/gdb/testsuite/gdb.mi/mi-frame-selection.c
new file mode 100644
index 00000000000..70b992c9149
--- /dev/null
+++ b/gdb/testsuite/gdb.mi/mi-frame-selection.c
@@ -0,0 +1,34 @@ 
+/* Copyright 2018 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+int
+frame_2 (void)
+{
+  return 0;
+}
+
+int
+frame_1 (void)
+{
+  return frame_2 ();
+}
+
+int
+main (void)
+{
+  return frame_1 ();
+}
diff --git a/gdb/testsuite/gdb.mi/mi-frame-selection.exp b/gdb/testsuite/gdb.mi/mi-frame-selection.exp
new file mode 100644
index 00000000000..e24c7179b9d
--- /dev/null
+++ b/gdb/testsuite/gdb.mi/mi-frame-selection.exp
@@ -0,0 +1,89 @@ 
+# Copyright 2018 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Test the frame selection syntax with the -stack-select-frame command.
+
+load_lib mi-support.exp
+set MIFLAGS "-i=mi"
+
+gdb_exit
+if [mi_gdb_start] {
+    continue
+}
+
+standard_testfile
+
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+    untested $testfile
+    return -1
+}
+
+mi_delete_breakpoints
+mi_gdb_reinitialize_dir $srcdir/$subdir
+mi_gdb_load ${binfile}
+
+mi_create_breakpoint "frame_2" \
+    "break-insert into frame_2" \
+    -number 1 -func frame_2 -file ".*${srcfile}"
+
+mi_run_cmd
+mi_expect_stop "breakpoint-hit" "frame_2" "" ".*${srcfile}" \
+	".*" { "" "disp=\"keep\"" } "run to breakpoint"
+
+mi_gdb_test "-stack-info-depth" \
+    "\\^done,depth=\"3\"" \
+    "stack info-depth"
+
+for {set i 0} {$i < 5} {incr i} {
+
+    if { $i < 3 } then {
+	mi_gdb_test "-stack-select-frame $i" \
+	    {\^done} \
+	    "-stack-select-frame $i"
+
+	mi_gdb_test "-stack-info-frame" \
+	    "\\^done,frame=\\\{level=\"$i\"\[^\}\]+\\\}" \
+	    "check level has has changed to $i"
+
+    } else {
+	mi_gdb_test "-stack-select-frame view $i" \
+	    {\^done} \
+	    "-stack-select-frame view frame at $i"
+
+	mi_gdb_test "-stack-info-frame" \
+	    "\\^done,frame=\\\{level=\"0\"\[^\}\]+\\\}" \
+	    "check level has has changed to 0, when creating a frame at sp=$i"
+    }
+}
+
+mi_gdb_test "-stack-select-frame 5" \
+    {\^error,msg="No frame at level 5."} \
+    "-stack-select-frame 5, with no keyword"
+
+mi_gdb_test "-stack-select-frame level 5" \
+    {\^error,msg="No frame at level 5."} \
+    "-stack-select-frame 5, using 'level' keyword"
+
+mi_gdb_test "-stack-select-frame function main" \
+    {\^done} \
+    "-stack-select-frame select frame for function main"
+
+mi_gdb_test "-stack-info-frame" \
+    "\\^done,frame=\\\{level=\"2\"\[^\}\]+\\\}" \
+    "check level has has changed to 2 for function main"
+
+mi_gdb_test "-stack-select-frame function unknown_function" \
+    {\^error,msg=\"Function \\\"unknown_function\\\" not defined.\"} \
+    "-stack-select-frame check error on undefined function name"