From patchwork Thu Jun 7 16:19:54 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tom Tromey X-Patchwork-Id: 27693 Received: (qmail 56977 invoked by alias); 7 Jun 2018 16:20:08 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Delivered-To: mailing list gdb-patches@sourceware.org Received: (qmail 56885 invoked by uid 89); 7 Jun 2018 16:20:08 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-25.9 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RCVD_IN_DNSWL_NONE, SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=52, 5.2, ending X-HELO: gateway30.websitewelcome.com Received: from gateway30.websitewelcome.com (HELO gateway30.websitewelcome.com) (192.185.146.7) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 07 Jun 2018 16:20:05 +0000 Received: from cm13.websitewelcome.com (cm13.websitewelcome.com [100.42.49.6]) by gateway30.websitewelcome.com (Postfix) with ESMTP id 7F5E2AA0D for ; Thu, 7 Jun 2018 11:20:04 -0500 (CDT) Received: from box5379.bluehost.com ([162.241.216.53]) by cmsmtp with SMTP id Qxdsfj1hH79N3QxdsfCvov; Thu, 07 Jun 2018 11:20:04 -0500 X-Authority-Reason: nr=8 Received: from 75-166-19-45.hlrn.qwest.net ([75.166.19.45]:33878 helo=bapiya.Home) by box5379.bluehost.com with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.91) (envelope-from ) id 1fQxds-000Qfd-3k; Thu, 07 Jun 2018 11:20:04 -0500 From: Tom Tromey To: gdb-patches@sourceware.org Cc: Tom Tromey Subject: [RFA v3 5/6] Add validity bits for psymtab high and low fields Date: Thu, 7 Jun 2018 10:19:54 -0600 Message-Id: <20180607161955.9800-6-tom@tromey.com> In-Reply-To: <20180607161955.9800-1-tom@tromey.com> References: <20180607161955.9800-1-tom@tromey.com> X-BWhitelist: no X-Source-L: No X-Exim-ID: 1fQxds-000Qfd-3k X-Source-Sender: 75-166-19-45.hlrn.qwest.net (bapiya.Home) [75.166.19.45]:33878 X-Source-Auth: tom+tromey.com X-Email-Count: 6 X-Source-Cap: ZWx5bnJvYmk7ZWx5bnJvYmk7Ym94NTM3OS5ibHVlaG9zdC5jb20= X-Local-Domain: yes Right now some psymtab code checks whether a psymtab's textlow or texthigh fields are valid by comparing against 0. I imagine this is mildly wrong in the current environment, but once psymtabs are relocated dynamically, it will no longer be correct, because it will be much more normal to see a psymtab with a textlow of zero -- this will just mean it appears at the start of the text section. This patch introduces validity bits to handle this situation more nicely, and changes users of the code to follow. gdb/ChangeLog 2018-06-07 Tom Tromey * dbxread.c (end_psymtab): Use texthigh_valid and textlow_valid. * mdebugread.c (parse_partial_symbols): Use textlow_valid. (psymtab_to_symtab_1): Use texthigh_valid and textlow_valid. * psympriv.h (struct partial_symtab) : Update comment. : New fields. : Update. * xcoffread.c (scan_xcoff_symtab): Use textlow_valid. --- gdb/ChangeLog | 11 +++++++++++ gdb/dbxread.c | 6 ++---- gdb/mdebugread.c | 8 ++++---- gdb/psympriv.h | 11 ++++++++++- gdb/xcoffread.c | 2 +- 5 files changed, 28 insertions(+), 10 deletions(-) diff --git a/gdb/dbxread.c b/gdb/dbxread.c index e011b5cf417..204937a9db8 100644 --- a/gdb/dbxread.c +++ b/gdb/dbxread.c @@ -2040,13 +2040,11 @@ dbx_end_psymtab (struct objfile *objfile, struct partial_symtab *pst, /* If we know our own starting text address, then walk through all other psymtabs for this objfile, and if any didn't know their ending text address, set it to our starting address. Take care to not set our - own ending address to our starting address, nor to set addresses on - `dependency' files that have both textlow and texthigh zero. */ + own ending address to our starting address. */ ALL_OBJFILE_PSYMTABS (objfile, p1) { - if (p1->text_high () == 0 && p1->text_low () != 0 - && p1 != pst) + if (!p1->texthigh_valid && p1->textlow_valid && p1 != pst) p1->set_text_high (pst->text_low ()); } } diff --git a/gdb/mdebugread.c b/gdb/mdebugread.c index 2699cb99b19..3deb8cf2a43 100644 --- a/gdb/mdebugread.c +++ b/gdb/mdebugread.c @@ -2737,7 +2737,7 @@ parse_partial_symbols (minimal_symbol_reader &reader, /* Kludge for Irix 5.2 zero fh->adr. */ if (!relocatable - && (pst->text_low () == 0 + && (!pst->textlow_valid || procaddr < pst->text_low ())) pst->set_text_low (procaddr); if (high > pst->text_high ()) @@ -3513,7 +3513,7 @@ parse_partial_symbols (minimal_symbol_reader &reader, /* Kludge for Irix 5.2 zero fh->adr. */ if (!relocatable - && (pst->text_low () == 0 + && (!pst->textlow_valid || procaddr < pst->text_low ())) pst->set_text_low (procaddr); @@ -3712,7 +3712,7 @@ parse_partial_symbols (minimal_symbol_reader &reader, other cases. */ save_pst = fdr_to_pst[f_idx].pst; if (save_pst != NULL - && save_pst->text_low () != 0 + && save_pst->textlow_valid && !(objfile->flags & OBJF_REORDERED)) { ALL_OBJFILE_PSYMTABS (objfile, pst) @@ -3923,7 +3923,7 @@ psymtab_to_symtab_1 (struct objfile *objfile, /* Do nothing if this is a dummy psymtab. */ if (pst->n_global_syms == 0 && pst->n_static_syms == 0 - && pst->text_low () == 0 && pst->text_high () == 0) + && !pst->textlow_valid && !pst->texthigh_valid) return; /* Now read the symbols for this symtab. */ diff --git a/gdb/psympriv.h b/gdb/psympriv.h index c1f1defd58c..30e81dbe5bc 100644 --- a/gdb/psympriv.h +++ b/gdb/psympriv.h @@ -114,12 +114,14 @@ struct partial_symtab void set_text_low (CORE_ADDR addr) { m_textlow = addr; + textlow_valid = 1; } /* Set the hight text address of this partial_symtab. */ void set_text_high (CORE_ADDR addr) { m_texthigh = addr; + texthigh_valid = 1; } @@ -144,7 +146,9 @@ struct partial_symtab /* Range of text addresses covered by this file; texthigh is the beginning of the next section. Do not use if PSYMTABS_ADDRMAP_SUPPORTED is set. Do not refer directly to these fields. Instead, use the - accessors. */ + accessors. The validity of these fields is determined by the + textlow_valid and texthigh_valid fields; these are located later + in this structure for better packing. */ CORE_ADDR m_textlow; CORE_ADDR m_texthigh; @@ -230,6 +234,11 @@ struct partial_symtab ENUM_BITFIELD (psymtab_search_status) searched_flag : 2; + /* Validity of the textlow_ and texthigh_ fields. */ + + unsigned int textlow_valid : 1; + unsigned int texthigh_valid : 1; + /* Pointer to compunit eventually allocated for this source file, 0 if !readin or if we haven't looked for the symtab after it was readin. */ diff --git a/gdb/xcoffread.c b/gdb/xcoffread.c index 5e621e608d7..cf402fabe30 100644 --- a/gdb/xcoffread.c +++ b/gdb/xcoffread.c @@ -2346,7 +2346,7 @@ scan_xcoff_symtab (minimal_symbol_reader &reader, if (highval > pst->text_high ()) pst->set_text_high (highval); - if (pst->text_low () == 0 + if (!pst->textlow_valid || symbol.n_value < pst->text_low ()) pst->set_text_low (symbol.n_value); }