Re: [PATCH v2 00/31] Baby step for objfile splitting

[Andrew Burgess <aburgess@redhat.com>]

Tom Tromey <tom@tromey.com> writes:

> Every year or so, I take a stab at the objfile splitting work.  This
> always fails and I end up not sending anything.

For those of us who aren't familiar with the background here.  Do you
have a link to a previous description of, or could you give a
description of, what the "objfile splitting work" is about.  What's the
longer term goal, of which this series is a step towards.

Thanks,
Andrew


>
> This year, I decided to take a baby step instead, thinking maybe it
> would be possible to slowly grind away at the problem.
>
> This series is the first such step.  It spreads the use of
> block_symbol through a bunch of code, trying to eliminate calls to
> symbol::value_address.
>
> The longer term idea here is to then add an objfile member to
> block_symbol.  After this, it would be relatively simple to change
> symbols to be relocated at point of use.  (This would be a significant
> step toward objfile splitting, but there's even more to do after
> that...)
>
> Regression tested on x86-64 Fedora 38.
>
> ---
> Changes in v2:
> - Updated per review
> - Added bound_symbol patch, converted some patches to use it
> - More comprehensive change in ada-lang.c
> - Link to v1: https://inbox.sourceware.org/gdb-patches/20231029-split-objfile-2023-bound-sym-october-v1-0-612531df2734@tromey.com
>
> ---
> Tom Tromey (31):
>       Introduce block-symbol.h
>       Add block_symbol::address
>       Add bound_symbol
>       Easy conversions to use block_symbol::address
>       Use block_symbol::address in ada-tasks.c
>       Use block_symbol::address in printcmd.c
>       Use bound_symbol::address in tracepoint.c
>       Use block_symbol::address in tracepoint.c
>       Use block_symbol::address in ax-gdb.c
>       Use block_symbol::address in linespec.c
>       Use block_symbol::address in ada-lang.c
>       Use bound_symbol::address in symmisc.c
>       Introduce read_var_value overload
>       Use read_var_value in gdb/compile
>       Return a block_symbol from find_pc_sect_function
>       Use read_var_value overload in finish_command_fsm
>       Use block_symbol in overload-handling code
>       Change evaluate_var_value to accept a block_symbol
>       Change value_of_variable to take a block_symbol
>       Return a block_symbol from get_frame_function
>       Use read_var_value overload in return_command
>       Use read_var_value overload in py-finishbreakpoint.c
>       Use read_var_value overload in py-framefilter.c
>       Use read_var_value overload in Guile
>       Use read_var_value in read_frame_arg and read_frame_local
>       Change print_variable_and_value to take a block_symbol
>       Change find_frame_funname to return a block_symbol
>       Change btrace_function::sym to a block_symbol
>       Use read_var_value overload in Python
>       Remove the old read_var_value
>       Change language_defn::read_var_value to accept block_symbol
>
>  gdb/ada-lang.c                      | 116 +++++++++++++----------------
>  gdb/ada-tasks.c                     |  19 ++---
>  gdb/ax-gdb.c                        |  28 +++----
>  gdb/ax-gdb.h                        |   2 +-
>  gdb/block-symbol.h                  |  42 +++++++++++
>  gdb/blockframe.c                    |  18 ++---
>  gdb/breakpoint.c                    |   4 +-
>  gdb/btrace.c                        |  38 +++++-----
>  gdb/btrace.h                        |   5 +-
>  gdb/cli/cli-cmds.c                  |   4 +-
>  gdb/compile/compile-c-symbols.c     |  18 +++--
>  gdb/compile/compile-cplus-symbols.c |   6 +-
>  gdb/compile/compile-cplus-types.c   |   2 +-
>  gdb/compile/compile-loc2c.c         |  14 ++--
>  gdb/compile/compile.h               |   6 +-
>  gdb/cp-support.c                    |  46 +++++++-----
>  gdb/cp-support.h                    |   6 +-
>  gdb/dwarf2/ada-imported.c           |   2 +-
>  gdb/dwarf2/loc.c                    |  16 ++--
>  gdb/dwarf2/loc.h                    |   3 +-
>  gdb/eval.c                          |  62 +++++++---------
>  gdb/expop.h                         |   5 ++
>  gdb/f-valprint.c                    |   4 +-
>  gdb/findvar.c                       |  24 +++---
>  gdb/frame.c                         |   2 +-
>  gdb/frame.h                         |   9 ++-
>  gdb/guile/guile-internal.h          |   2 +-
>  gdb/guile/scm-block.c               |   6 +-
>  gdb/guile/scm-frame.c               |   7 +-
>  gdb/guile/scm-symbol.c              |  78 ++++++++++----------
>  gdb/infcall.c                       |   4 +-
>  gdb/infcmd.c                        |  29 ++++----
>  gdb/infrun.c                        |  10 +--
>  gdb/inline-frame.c                  |   2 +-
>  gdb/language.h                      |  14 +---
>  gdb/linespec.c                      |  15 ++--
>  gdb/mi/mi-cmd-stack.c               |  20 ++---
>  gdb/printcmd.c                      |  22 +++---
>  gdb/python/py-block.c               |   6 +-
>  gdb/python/py-finishbreakpoint.c    |  11 +--
>  gdb/python/py-frame.c               |  15 ++--
>  gdb/python/py-framefilter.c         |  64 +++++++---------
>  gdb/python/py-objfile.c             |  16 ++--
>  gdb/python/py-record-btrace.c       |   2 +-
>  gdb/python/py-symbol.c              | 143 ++++++++++++++++++------------------
>  gdb/python/py-type.c                |   2 +-
>  gdb/python/py-unwind.c              |   4 +-
>  gdb/python/python-internal.h        |   4 +-
>  gdb/record-btrace.c                 |   8 +-
>  gdb/rust-lang.c                     |   2 +-
>  gdb/skip.c                          |   2 +-
>  gdb/solib-frv.c                     |   2 +-
>  gdb/sparc-tdep.c                    |   4 +-
>  gdb/stack.c                         |  59 ++++++++-------
>  gdb/stack.h                         |   2 +-
>  gdb/symmisc.c                       |  15 ++--
>  gdb/symtab.c                        |   4 +-
>  gdb/symtab.h                        |  38 +++++++---
>  gdb/tracepoint.c                    |  26 ++++---
>  gdb/tracepoint.h                    |   2 +-
>  gdb/valarith.c                      |   9 +--
>  gdb/valops.c                        |  75 ++++++++++---------
>  gdb/value.c                         |   2 +-
>  gdb/value.h                         |  18 ++---
>  64 files changed, 647 insertions(+), 598 deletions(-)
> ---
> base-commit: 0a845aef62b8813275616bd399e8fca679161cfc
> change-id: 20231029-split-objfile-2023-bound-sym-october-8da7ff1061cc
>
> Best regards,
> -- 
> Tom Tromey <tom@tromey.com>