From patchwork Thu Aug 28 10:46:08 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yao Qi X-Patchwork-Id: 2566 Received: (qmail 31331 invoked by alias); 28 Aug 2014 10:50:19 -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 31316 invoked by uid 89); 28 Aug 2014 10:50:18 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.7 required=5.0 tests=AWL, BAYES_00 autolearn=ham version=3.3.2 X-HELO: relay1.mentorg.com Received: from relay1.mentorg.com (HELO relay1.mentorg.com) (192.94.38.131) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 28 Aug 2014 10:50:16 +0000 Received: from svr-orw-fem-06.mgc.mentorg.com ([147.34.97.120]) by relay1.mentorg.com with esmtp id 1XMxHQ-0007GJ-Aa from Yao_Qi@mentor.com ; Thu, 28 Aug 2014 03:50:12 -0700 Received: from GreenOnly (147.34.91.1) by SVR-ORW-FEM-06.mgc.mentorg.com (147.34.97.120) with Microsoft SMTP Server id 14.2.247.3; Thu, 28 Aug 2014 03:50:11 -0700 From: Yao Qi To: Doug Evans CC: Subject: Re: [PATCH 1/3] Check function is GC'ed References: <53D8A264.1050103@codesourcery.com> <1408609338-17561-1-git-send-email-yao@codesourcery.com> <21495.32892.341399.802579@ruffy2.mtv.corp.google.com> Date: Thu, 28 Aug 2014 18:46:08 +0800 In-Reply-To: <21495.32892.341399.802579@ruffy2.mtv.corp.google.com> (Doug Evans's message of "Fri, 22 Aug 2014 10:40:12 -0700") Message-ID: <87sikggadr.fsf@codesourcery.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 X-IsSubscribed: yes Doug Evans writes: > I'd like to solve this for both partial syms and .gdb_index. > > We want to, essentially, discard the entry if address is outside the > range of the cu (the range needn't be contiguous, but for the task > at hand I don't think it matters). I haven't dug into this too deeply, > but if we have lowpc (which for example is that read_file_scope has > before it calls handle_DW_AT_stmt_list (which calls dwarf_decode_lines), > can we use that in the test? Can we arrange for all callers of > dwarf_decode_lines_1 pass lowpc down to it? [Or both lowpc,highpc > for a more complete test, but for the task at hand we've only been > checking, effectively, lowpc all along so I don't mind leaving it at that > for now.] Hi Doug, Patch below implemented what you suggested, if I understand you correct :) A new argument 'lowpc' is added to both dwarf2_build_include_psymtabs and handle_DW_AT_stmt_list, to keep the similarity between them. I thought about merging them into one function, but still need more thinking. diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c index be32309..8fdae74 100644 --- a/gdb/dwarf2read.c +++ b/gdb/dwarf2read.c @@ -1512,7 +1512,8 @@ static struct line_header *dwarf_decode_line_header (unsigned int offset, struct dwarf2_cu *cu); static void dwarf_decode_lines (struct line_header *, const char *, - struct dwarf2_cu *, struct partial_symtab *); + struct dwarf2_cu *, struct partial_symtab *, + CORE_ADDR); static void dwarf2_start_subfile (const char *, const char *, const char *); @@ -4436,7 +4437,8 @@ dwarf2_create_include_psymtab (const char *name, struct partial_symtab *pst, static void dwarf2_build_include_psymtabs (struct dwarf2_cu *cu, struct die_info *die, - struct partial_symtab *pst) + struct partial_symtab *pst, + CORE_ADDR lowpc) { struct line_header *lh = NULL; struct attribute *attr; @@ -4448,7 +4450,7 @@ dwarf2_build_include_psymtabs (struct dwarf2_cu *cu, return; /* No linetable, so no includes. */ /* NOTE: pst->dirname is DW_AT_comp_dir (if present). */ - dwarf_decode_lines (lh, pst->dirname, cu, pst); + dwarf_decode_lines (lh, pst->dirname, cu, pst, lowpc); free_line_header (lh); } @@ -5954,7 +5956,7 @@ process_psymtab_comp_unit_reader (const struct die_reader_specs *reader, /* Get the list of files included in the current compilation unit, and build a psymtab for each of them. */ - dwarf2_build_include_psymtabs (cu, comp_unit_die, pst); + dwarf2_build_include_psymtabs (cu, comp_unit_die, pst, pst->textlow); if (dwarf2_read_debug) { @@ -8967,11 +8969,12 @@ find_file_and_directory (struct die_info *die, struct dwarf2_cu *cu, /* Handle DW_AT_stmt_list for a compilation unit. DIE is the DW_TAG_compile_unit die for CU. - COMP_DIR is the compilation directory. */ + COMP_DIR is the compilation directory. LOWPC is passed to + dwarf_decode_lines. See dwarf_decode_lines comments about it. */ static void handle_DW_AT_stmt_list (struct die_info *die, struct dwarf2_cu *cu, - const char *comp_dir) /* ARI: editCase function */ + const char *comp_dir, CORE_ADDR lowpc) /* ARI: editCase function */ { struct attribute *attr; @@ -8988,7 +8991,7 @@ handle_DW_AT_stmt_list (struct die_info *die, struct dwarf2_cu *cu, { cu->line_header = line_header; make_cleanup (free_cu_line_header, cu); - dwarf_decode_lines (line_header, comp_dir, cu, NULL); + dwarf_decode_lines (line_header, comp_dir, cu, NULL, lowpc); } } } @@ -9039,7 +9042,7 @@ read_file_scope (struct die_info *die, struct dwarf2_cu *cu) /* Decode line number information if present. We do this before processing child DIEs, so that the line header table is available for DW_AT_decl_file. */ - handle_DW_AT_stmt_list (die, cu, comp_dir); + handle_DW_AT_stmt_list (die, cu, comp_dir, lowpc); /* Process all dies in compilation unit. */ if (die->child != NULL) @@ -17252,7 +17255,8 @@ dwarf_finish_line (struct gdbarch *gdbarch, struct subfile *subfile, static void dwarf_decode_lines_1 (struct line_header *lh, const char *comp_dir, - struct dwarf2_cu *cu, const int decode_for_pst_p) + struct dwarf2_cu *cu, const int decode_for_pst_p, + CORE_ADDR lowpc) { const gdb_byte *line_ptr, *extended_end; const gdb_byte *line_end; @@ -17375,7 +17379,9 @@ dwarf_decode_lines_1 (struct line_header *lh, const char *comp_dir, case DW_LNE_set_address: address = read_address (abfd, line_ptr, cu, &bytes_read); - if (address == 0 && !dwarf2_per_objfile->has_section_at_zero) + if (address == 0 + && (!dwarf2_per_objfile->has_section_at_zero + || lowpc > address)) { /* This line table is for a function which has been GCd by the linker. Ignore it. PR gdb/12528 */ @@ -17595,17 +17601,20 @@ dwarf_decode_lines_1 (struct line_header *lh, const char *comp_dir, as the corresponding symtab. Since COMP_DIR is not used in the name of the symtab we don't use it in the name of the psymtabs we create. E.g. expand_line_sal requires this when finding psymtabs to expand. - A good testcase for this is mb-inline.exp. */ + A good testcase for this is mb-inline.exp. + + LOWPC is the lowest address in CU (or 0 if not known). */ static void dwarf_decode_lines (struct line_header *lh, const char *comp_dir, - struct dwarf2_cu *cu, struct partial_symtab *pst) + struct dwarf2_cu *cu, struct partial_symtab *pst, + CORE_ADDR lowpc) { struct objfile *objfile = cu->objfile; const int decode_for_pst_p = (pst != NULL); struct subfile *first_subfile = current_subfile; - dwarf_decode_lines_1 (lh, comp_dir, cu, decode_for_pst_p); + dwarf_decode_lines_1 (lh, comp_dir, cu, decode_for_pst_p, lowpc); if (decode_for_pst_p) { diff --git a/gdb/testsuite/gdb.base/break-on-linker-gcd-function.exp b/gdb/testsuite/gdb.base/break-on-linker-gcd-function.exp index e593b51..b8de1cd 100644 --- a/gdb/testsuite/gdb.base/break-on-linker-gcd-function.exp +++ b/gdb/testsuite/gdb.base/break-on-linker-gcd-function.exp @@ -41,9 +41,23 @@ if {[build_executable_from_specs $testfile.exp $testfile \ clean_restart $testfile -# Single hex digit -set xd {[0-9a-f]} +proc set_breakpoint_on_gcd_function {} { + # Single hex digit + set xd {[0-9a-f]} + + # This accepts e.g. "Breakpoint 1 at 0x40968a" (fixed GDB) + # but rejects e.g. "Breakpoint 1 at 0x4" (broken GDB). + gdb_test "b [gdb_get_line_number "gdb break here"]" \ + "Breakpoint \[0-9\] at 0x${xd}${xd}+: .*" +} + +set_breakpoint_on_gcd_function -# This accepts e.g. "Breakpoint 1 at 0x40968a" (fixed GDB) -# but rejects e.g. "Breakpoint 1 at 0x4" (broken GDB). -gdb_test "b [gdb_get_line_number "gdb break here"]" "Breakpoint \[0-9\] at 0x${xd}${xd}+: .*" +set saved_gdbflags $GDBFLAGS +set GDBFLAGS "$GDBFLAGS --readnow" +clean_restart ${testfile} +set GDBFLAGS $saved_gdbflags + +with_test_prefix "readnow" { + set_breakpoint_on_gcd_function +}