From: Michael Matz <matz@sourceware.org>
To: bfd-cvs@sourceware.org
Subject: [binutils-gdb] section-select: Fix performance problem (PR30367)
Date: Tue, 25 Apr 2023 12:58:35 +0000 (GMT) [thread overview]
Message-ID: <20230425125835.B958F3858D1E@sourceware.org> (raw)
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=8f5cd47bee6c07c33aeda758d8d8db5f81ae03e7
commit 8f5cd47bee6c07c33aeda758d8d8db5f81ae03e7
Author: Michael Matz <matz@suse.de>
Date: Tue Apr 18 16:16:01 2023 +0200
section-select: Fix performance problem (PR30367)
when using many wild-statements with non-wildcard filenames we
were running into quadraticness via repeatedly using lookup_name
on a long list of loaded files. I've originally retained using
lookup_name because that preserved existing behaviour most obviously.
In particular in matching wild-statements when using a non-wildcard
filename it matches against local_sym_name, not the filename member.
If the wildspec would have an archive-spec or a wildcard it would use
the filename member, though. Also it would load the named file
(and ignore it, as being not equal to the currently considered
input-statement).
Rewrite this to not use lookup_name but retain the comparison
against local_sym_name with a comment to that effect.
PR 30367
* ldlang.c (walk_wild_section_match): Don't use lookup_name
but directly compare spec and local_sym_name.
Diff:
---
ld/ldlang.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/ld/ldlang.c b/ld/ldlang.c
index 006031b5a65..9ad405aa06c 100644
--- a/ld/ldlang.c
+++ b/ld/ldlang.c
@@ -433,10 +433,18 @@ walk_wild_section_match (lang_wild_statement_type *ptr,
}
else
{
- lang_input_statement_type *f;
- /* Perform the iteration over a single file. */
- f = lookup_name (file_spec);
- if (f != file)
+ /* XXX Matching against non-wildcard filename in wild statements
+ was done by going through lookup_name, which uses
+ ->local_sym_name to compare against, not ->filename. We retain
+ this behaviour even though the above code paths use filename.
+ It would be more logical to use it here as well, in which
+ case the above wildcard() arm could be folded into this by using
+ name_match. This would also solve the worry of what to do
+ about unset local_sym_name (in which case lookup_name simply adds
+ the input file again). */
+ const char *filename = file->local_sym_name;
+ if (filename == NULL
+ || filename_cmp (filename, file_spec) != 0)
return;
}
reply other threads:[~2023-04-25 12:58 UTC|newest]
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