Re: [PATCH dwarves 0/2] dwarf_loader: improve cus__merging_cu()

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Wed, Mar 31, 2021 at 07:58:15PM -0700, Yonghong Song escreveu:
> Function cus__merging_cu() is introduced in Commit 39227909db3c
> ("dwarf_loader: Permit merging all DWARF CU's for clang LTO built
> binary") to test whether cross-cu references may happen.
> The original implementation anticipates compilation flags
> in dwarf, but later some concerns about binary size surfaced
> and the decision is to scan .debug_abbrev as a faster way
> to check cross-cu references. Also putting a note in vmlinux
> to indicate whether lto is enabled for built or not can
> provide a much faster way.

Great work! Reviewing/testing right now.

- Arnaldo
 
> This patch set implemented this two approaches, first
> checking the note (in Patch #2), if not found, then
> check .debug_abbrev (in Patch #1).
> 
> Yonghong Song (2):
>   dwarf_loader: check .debug_abbrev for cross-cu references
>   dwarf_loader: check .notes section for lto build info
> 
>  dwarf_loader.c | 76 ++++++++++++++++++++++++++++++++++++--------------
>  1 file changed, 55 insertions(+), 21 deletions(-)
> 
> -- 
> 2.30.2
> 

-- 

- Arnaldo