From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 23753 invoked by alias); 6 Aug 2008 14:12:29 -0000 Received: (qmail 23738 invoked by uid 22791); 6 Aug 2008 14:12:24 -0000 X-Spam-Check-By: sourceware.org Received: from main.gmane.org (HELO ciao.gmane.org) (80.91.229.2) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 06 Aug 2008 14:11:25 +0000 Received: from list by ciao.gmane.org with local (Exim 4.43) id 1KQjjW-0008HQ-Cn for gdb-patches@sources.redhat.com; Wed, 06 Aug 2008 14:11:22 +0000 Received: from entropy.qnx.com ([209.226.137.107]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 06 Aug 2008 14:11:22 +0000 Received: from aristovski by entropy.qnx.com with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 06 Aug 2008 14:11:22 +0000 To: gdb-patches@sources.redhat.com From: Aleksandar Ristovski Subject: [patch] step over permanent breakpoint Date: Wed, 06 Aug 2008 14:12:00 -0000 Message-ID: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="------------060205030607020800070407" User-Agent: Thunderbird 2.0.0.16 (Windows/20080708) X-IsSubscribed: yes 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 X-SW-Source: 2008-08/txt/msg00113.txt.bz2 This is a multi-part message in MIME format. --------------060205030607020800070407 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-length: 355 Hello, I encountered a problem when setting a breakpoint over a permanent breakpoint. GDB did not handle this situation correctly. The attached test demonstrates the problem, and the patch fixes it for i386 architecture. For other architectures, skip_permanent_breakpoint needs to be implemented. Thanks, Aleksandar Ristovski QNX Software Systems --------------060205030607020800070407 Content-Type: text/plain; name="i386_permanent_breakpoints-20080805.diff.ChangeLog" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="i386_permanent_breakpoints-20080805.diff.ChangeLog" Content-length: 466 2008-08-05 Aleksandar Ristovski * breakpoint.c (breakpoint_init_inferior): Mark as not inserted only non-permanent breakpoints. (create_breakpoint): Check if the location points to a permanent breakpoint. (update_breakpoint_locations): Make sure new locations of permanent breakpoints are properly initialized. * i386-tdep.c (i386_skip_permanent_breakpoint): New function. (i386_gdbarch_init): Set gdbarch_skip_permanent_breakpoint. --------------060205030607020800070407 Content-Type: text/plain; name="i386_permanent_breakpoints-20080805.diff" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="i386_permanent_breakpoints-20080805.diff" Content-length: 3016 Index: gdb/breakpoint.c =================================================================== RCS file: /cvs/src/src/gdb/breakpoint.c,v retrieving revision 1.338 diff -u -p -r1.338 breakpoint.c --- gdb/breakpoint.c 28 Jul 2008 17:53:52 -0000 1.338 +++ gdb/breakpoint.c 5 Aug 2008 20:32:55 -0000 @@ -1720,7 +1720,10 @@ breakpoint_init_inferior (enum inf_conte struct bp_location *bpt; ALL_BP_LOCATIONS (bpt) - bpt->inserted = 0; + { + if (bpt->owner->enable_state != bp_permanent) + bpt->inserted = 0; + } ALL_BREAKPOINTS_SAFE (b, temp) { @@ -3058,7 +3061,8 @@ bpstat_stop_status (CORE_ADDR bp_addr, p /* We will stop here */ if (b->disposition == disp_disable) { - b->enable_state = bp_disabled; + if (b->enable_state != bp_permanent) + b->enable_state = bp_disabled; update_global_location_list (0); } if (b->silent) @@ -5100,6 +5104,22 @@ create_breakpoint (struct symtabs_and_li loc = add_location_to_breakpoint (b, type, &sal); } + /* Check if the location points to permanent breakpoint. */ + if (loc != NULL) + { + int len; + CORE_ADDR addr = loc->address; + const gdb_byte *brk = gdbarch_breakpoint_from_pc (current_gdbarch, + &addr, &len); + gdb_byte target_mem[32]; + if (!target_read_memory (loc->address, target_mem, len)) + { + /* We have the target memory here. */ + if (memcmp (target_mem, brk, len) == 0) + make_breakpoint_permanent (b); + } + } + if (b->cond_string) { char *arg = b->cond_string; @@ -7437,6 +7457,10 @@ update_breakpoint_locations (struct brea b->line_number = sals.sals[i].line; } + /* Update locationos of permanent breakpoints. */ + if (b->enable_state == bp_permanent) + make_breakpoint_permanent (b); + /* If possible, carry over 'disable' status from existing breakpoints. */ { struct bp_location *e = existing_locations; Index: gdb/i386-tdep.c =================================================================== RCS file: /cvs/src/src/gdb/i386-tdep.c,v retrieving revision 1.261 diff -u -p -r1.261 i386-tdep.c --- gdb/i386-tdep.c 3 Jul 2008 00:19:58 -0000 1.261 +++ gdb/i386-tdep.c 5 Aug 2008 20:32:55 -0000 @@ -2550,6 +2550,17 @@ i386_fetch_pointer_argument (struct fram return read_memory_unsigned_integer (sp + (4 * (argi + 1)), 4); } +/* On i386, breakpoint is exactly 1 byte long, so we just + adjust the PC in the regcache. */ +static void +i386_skip_permanent_breakpoint (struct regcache *regcache) +{ + CORE_ADDR current_pc = regcache_read_pc (regcache); + current_pc += 1; + regcache_write_pc (regcache, current_pc); +} + + static struct gdbarch * i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) @@ -2738,6 +2749,9 @@ i386_gdbarch_init (struct gdbarch_info i if (tdep->mm0_regnum == 0) tdep->mm0_regnum = gdbarch_num_regs (gdbarch); + set_gdbarch_skip_permanent_breakpoint (gdbarch, + i386_skip_permanent_breakpoint); + return gdbarch; } --------------060205030607020800070407 Content-Type: text/plain; name="i386-bp_permanent.exp.ChangeLog" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="i386-bp_permanent.exp.ChangeLog" Content-length: 93 2008-08-05 Aleksandar Ristovski * i386-bp_permanent.exp: New test. --------------060205030607020800070407 Content-Type: text/plain; name="i386-bp_permanent.exp" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="i386-bp_permanent.exp" Content-length: 3183 # Copyright (C) 2003, 2004, 2006, 2007, 2008 Free Software Foundation, Inc. # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see . # Please email any bugs, comments, and/or additions to this file to: # bug-gdb@gnu.org # This file is part of the gdb testsuite. if $tracelevel { strace $tracelevel } # Test i386 prologue analyzer. set prms_id 0 set bug_id 0 if ![istarget "i?86-*-*"] then { verbose "Skipping i386 prologue tests." return } set testfile "i386-prologue" set srcfile ${testfile}.c set binfile ${objdir}/${subdir}/${testfile} # some targets have leading underscores on assembly symbols. # TODO: detect this automatically set additional_flags "" if [istarget "i?86-*-cygwin*"] then { set additional_flags "additional_flags=-DSYMBOL_PREFIX=\"_\"" } # Don't use "debug", so that we don't have line information for the assembly # fragments. if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable [list $additional_flags]] != "" } { untested i386-prologue.exp return -1 } gdb_exit gdb_start gdb_reinitialize_dir $srcdir/$subdir gdb_load ${binfile} # # Run to `main' where we begin our tests. # if ![runto_main] then { gdb_suppress_tests } # Testcase for standard prologue. send_gdb "disassemble standard\n"; gdb_expect 60 { -re ".*($hex) .*($hex) .*($hex) .*($hex) .*" { set standard_start $expect_out(1,string); set address $expect_out(2,string); set address1 $expect_out(3,string); set address2 $expect_out(4,string); } default { send_user "Oops, can't find address\n" gdb_supress_tests } } gdb_breakpoint "*$standard_start" gdb_breakpoint "*$address" gdb_test "continue" "Breakpoint .*, $standard_start in standard.*" \ "Stop at the standard start breakpoint (fetching esp)." # We want to fetch esp at the start of 'standard' function to make sure # skip_permanent_breakpoint implementation really skips only the perm. # breakpoint. If, for whatever reason, 'leave' instruction doesn't get # executed, esp will not have this value. send_gdb "print \$esp\n" gdb_expect 60 { -re ".1.*($hex).*" { set start_esp $expect_out(1,string); } default { gdb_fail "Fetching esp failed." } } gdb_test "continue" "Breakpoint .*, $address in standard.*" \ "Stop at permanent breakpoint." gdb_test "stepi" "$address1|$address2 in standard.*" \ "Single stepping past permanent breakpoint." gdb_test "print \$esp" ".*$start_esp.*" \ "ESP value does not match - step_permanent_breakpoint wrong." --------------060205030607020800070407--