[PATCH] Convert some frame functions to use gdb::array_view.

[Simon Marchi]

On 2021-01-19 8:31 a.m., Luis Machado via Gdb-patches wrote:
> This patch converts the most obvious functions from gdb/frame.h to use
> the gdb::array_view abstraction.  I've converted the ones that used buffer +
> length.
> 
> There are others using only the buffer, with an implicit size. I did not
> touch those for now. But it would be nice to pass the size for safety.
> 
> Tested with --enable-targets=all on Ubuntu 18.04/20.04 aarch64-linux.
> 
> gdb/ChangeLog
> 
> YYYY-MM-DD  Luis Machado  <luis.machado@linaro.org>
> 
> 	* frame.h (get_frame_register_bytes): Pass a gdb::array_view instead
> 	of buffer + length.
> 	(put_frame_register_bytes): Likewise.
> 	Adjust documentation.
> 	(get_frame_memory): Pass a gdb::array_view instead of buffer + length.
> 	(safe_frame_unwind_memory): Likewise.
> 	* frame.c (get_frame_register_bytes, put_frame_register_bytes)
> 	(get_frame_memory, safe_frame_unwind_memory): Adjust to use
> 	gdb::array_view.
> 	* amd64-fbsd-tdep.c (amd64fbsd_sigtramp_p): Likewise.
> 	* amd64-linux-tdep.c (amd64_linux_sigtramp_start): Likewise.
> 	* amd64-obsd-tdep.c (amd64obsd_sigtramp_p): Likewise.
> 	* arc-linux-tdep.c (arc_linux_is_sigtramp): Likewise.
> 	* cris-tdep.c (cris_sigtramp_start, cris_rt_sigtramp_start): Likewise.
> 	* dwarf2/loc.c (rw_pieced_value): Likewise.
> 	* hppa-tdep.c (hppa_frame_cache): Likewise.
> 	* i386-fbsd-tdep.c (i386fbsd_sigtramp_p): Likewise.
> 	* i386-gnu-tdep.c (i386_gnu_sigtramp_start): Likewise.
> 	* i386-linux-tdep.c (i386_linux_sigtramp_start)
> 	(i386_linux_rt_sigtramp_start): Likewise.
> 	* i386-obsd-tdep.c (i386obsd_sigtramp_p): Likewise.
> 	* i386-tdep.c (i386_register_to_value): Likewise.
> 	* i387-tdep.c (i387_register_to_value): Likewise.
> 	* ia64-tdep.c (ia64_register_to_value): Likewise.
> 	* m32r-linux-tdep.c (m32r_linux_sigtramp_start)
> 	(m32r_linux_rt_sigtramp_start): Likewise.
> 	* m68k-linux-tdep.c (m68k_linux_pc_in_sigtramp): Likewise.
> 	* m68k-tdep.c (m68k_register_to_value): Likewise.
> 	* mips-tdep.c (mips_register_to_value)
> 	(mips_value_to_register): Likewise.
> 	* ppc-fbsd-tdep.c (ppcfbsd_sigtramp_frame_sniffer)
> 	(ppcfbsd_sigtramp_frame_cache): Likewise.
> 	* ppc-obsd-tdep.c (ppcobsd_sigtramp_frame_sniffer)
> 	(ppcobsd_sigtramp_frame_cache): Likewise.
> 	* rs6000-tdep.c (rs6000_in_function_epilogue_frame_p)
> 	(rs6000_register_to_value): Likewise.
> 	* tilegx-tdep.c (tilegx_analyze_prologue): Likewise.
> 	* tramp-frame.c (tramp_frame_start): Likewise.
> 	* valops.c (value_assign): Likewise.
> ---
>  gdb/amd64-fbsd-tdep.c  |  2 +-
>  gdb/amd64-linux-tdep.c |  4 ++--
>  gdb/amd64-obsd-tdep.c  |  2 +-
>  gdb/arc-linux-tdep.c   |  4 ++--
>  gdb/cris-tdep.c        |  8 ++++----
>  gdb/dwarf2/loc.c       |  6 +++---
>  gdb/frame.c            | 20 ++++++++++++++------
>  gdb/frame.h            | 16 ++++++++--------
>  gdb/hppa-tdep.c        |  2 +-
>  gdb/i386-fbsd-tdep.c   | 16 ++++++++--------
>  gdb/i386-gnu-tdep.c    |  2 +-
>  gdb/i386-linux-tdep.c  | 10 +++++-----
>  gdb/i386-obsd-tdep.c   |  2 +-
>  gdb/i386-tdep.c        |  6 ++++--
>  gdb/i387-tdep.c        |  6 ++++--
>  gdb/ia64-tdep.c        |  6 ++++--
>  gdb/m32r-linux-tdep.c  | 10 +++++-----
>  gdb/m68k-linux-tdep.c  |  2 +-
>  gdb/m68k-tdep.c        |  6 ++++--
>  gdb/mips-tdep.c        | 18 +++++++++---------
>  gdb/ppc-fbsd-tdep.c    |  4 ++--
>  gdb/ppc-obsd-tdep.c    |  4 ++--
>  gdb/rs6000-tdep.c      | 12 ++++++++----
>  gdb/tilegx-tdep.c      |  2 +-
>  gdb/tramp-frame.c      |  7 ++++---
>  gdb/valops.c           | 12 ++++++------
>  26 files changed, 105 insertions(+), 84 deletions(-)
> 
> diff --git a/gdb/amd64-fbsd-tdep.c b/gdb/amd64-fbsd-tdep.c
> index 6a7000e7530..c0da5434537 100644
> --- a/gdb/amd64-fbsd-tdep.c
> +++ b/gdb/amd64-fbsd-tdep.c
> @@ -52,7 +52,7 @@ amd64fbsd_sigtramp_p (struct frame_info *this_frame)
>    CORE_ADDR pc = get_frame_pc (this_frame);
>    gdb_byte buf[sizeof amd64fbsd_sigtramp_code];
>  
> -  if (!safe_frame_unwind_memory (this_frame, pc, buf, sizeof buf))
> +  if (!safe_frame_unwind_memory (this_frame, pc, {buf, sizeof buf}))

When passing a static array, you can just pass it directly (just buf).  The array
view will get the size information from the array's type.

Otherwise, LGTM.

Simon