From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 1193 invoked by alias); 20 Sep 2019 01:01:02 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 1095 invoked by uid 89); 20 Sep 2019 01:01:01 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-18.9 required=5.0 tests=AWL,BAYES_00,GIT_PATCH_0,GIT_PATCH_1,GIT_PATCH_2,GIT_PATCH_3,SPF_HELO_PASS,SPF_PASS autolearn=ham version=3.3.1 spammy= X-HELO: simark.ca Received: from simark.ca (HELO simark.ca) (158.69.221.121) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 20 Sep 2019 01:00:59 +0000 Received: from [10.0.0.11] (unknown [192.222.164.54]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPSA id BD0601E05A; Thu, 19 Sep 2019 21:00:57 -0400 (EDT) Subject: Re: [PATCH v3] Replace solib_global_lookup with gdbarch_iterate_over_objfiles_in_search_order To: Christian Biesinger , gdb-patches@sourceware.org References: <20190827213752.204025-1-cbiesinger@google.com> <20190827230330.89757-1-cbiesinger@google.com> From: Simon Marchi Message-ID: <5a2bc785-4ecd-0c21-10b0-ab8f3d17aa02@simark.ca> Date: Fri, 20 Sep 2019 01:01:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.0 MIME-Version: 1.0 In-Reply-To: <20190827230330.89757-1-cbiesinger@google.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2019-09/txt/msg00388.txt.bz2 On 2019-08-27 7:03 p.m., Christian Biesinger via gdb-patches wrote: > [Test solib-corrupted.exp is now fixed] > > All implementations of either function use it for the same purpose (except > Darwin, which is a no-op): to prefer a symbol in the current objfile over > symbols with the same name in other objfiles. There does not seem to be a > reason to have both mechanisms for that purpose. Hi Christian, The patch LGTM, I'm also confident that it doesn't change the current behavior. I just have two very minor comments below. Note that SPU support is about to be removed [1]. If you wait until it is removed, it would simplify a bit this patch, as you wish. [1] https://sourceware.org/ml/gdb-patches/2019-09/msg00067.html > @@ -3202,32 +3204,41 @@ svr4_lp64_fetch_link_map_offsets (void) > > struct target_so_ops svr4_so_ops; > > -/* Lookup global symbol for ELF DSOs linked with -Bsymbolic. Those DSOs have a > +/* Search order for ELF DSOs linked with -Bsymbolic. Those DSOs have a > different rule for symbol lookup. The lookup begins here in the DSO, not in > the main executable. */ > > -static struct block_symbol > -elf_lookup_lib_symbol (struct objfile *objfile, > - const char *name, > - const domain_enum domain) > +void > +svr4_iterate_over_objfiles_in_search_order > + (struct gdbarch *gdbarch, > + iterate_over_objfiles_in_search_order_cb_ftype *cb, > + void *cb_data, struct objfile *current_objfile) > { > - bfd *abfd; > - > - if (objfile == symfile_objfile) > - abfd = exec_bfd; > - else > + if (current_objfile != nullptr) > { > - /* OBJFILE should have been passed as the non-debug one. */ > - gdb_assert (objfile->separate_debug_objfile_backlink == NULL); > + bfd *abfd; > > - abfd = objfile->obfd; > - } > + if (current_objfile->separate_debug_objfile_backlink != nullptr) > + current_objfile = current_objfile->separate_debug_objfile_backlink; > > - if (abfd == NULL || scan_dyntag (DT_SYMBOLIC, abfd, NULL, NULL) != 1) > - return {}; > + if (current_objfile == symfile_objfile) > + abfd = exec_bfd; > + else > + abfd = current_objfile->obfd; > + > + if (abfd != nullptr && > + scan_dyntag (DT_SYMBOLIC, abfd, nullptr, nullptr) == 1) > + { > + if (cb (current_objfile, cb_data) != 0) > + return; > + } > + } > > - return lookup_global_symbol_from_objfile (objfile, GLOBAL_BLOCK, name, > - domain); > + for (objfile *objfile : current_program_space->objfiles ()) > + { > + if (cb (objfile, cb_data) != 0) > + return; > + } > } If we do search the current objfile in the first part of that function, we could skip it in the second part. > diff --git a/gdb/solib-svr4.h b/gdb/solib-svr4.h > index a051e70b79..b99b8e2e3a 100644 > --- a/gdb/solib-svr4.h > +++ b/gdb/solib-svr4.h > @@ -21,6 +21,7 @@ > #define SOLIB_SVR4_H > > #include "solist.h" > +#include "gdbarch.h" Could this be a forward declaration of `struct gdbarch` instead? Though if you wait until SPU is removed, the function svr4_iterate_over_objfiles_in_search_order won't need to be exported, it should be made static. Simon