From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11608 invoked by alias); 1 Oct 2008 19:21:02 -0000 Received: (qmail 11590 invoked by uid 22791); 1 Oct 2008 19:21:01 -0000 X-Spam-Check-By: sourceware.org Received: from smtp-outbound-1.vmware.com (HELO smtp-outbound-1.vmware.com) (65.113.40.141) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 01 Oct 2008 19:20:25 +0000 Received: from mailhost4.vmware.com (mailhost4.vmware.com [10.16.67.124]) by smtp-outbound-1.vmware.com (Postfix) with ESMTP id 58B95679D; Wed, 1 Oct 2008 12:20:22 -0700 (PDT) Received: from [10.20.92.59] (promb-2s-dhcp59.eng.vmware.com [10.20.92.59]) by mailhost4.vmware.com (Postfix) with ESMTP id 7152FC9A9D; Wed, 1 Oct 2008 12:20:22 -0700 (PDT) Message-ID: <48E3CD40.3070206@vmware.com> Date: Wed, 01 Oct 2008 19:21:00 -0000 From: Michael Snyder User-Agent: Thunderbird 1.5.0.12 (X11/20080411) MIME-Version: 1.0 To: "gdb-patches@sourceware.org" CC: Daniel Jacobowitz , Pedro Alves , teawater Subject: [RFA] Reverse Debugging, 4/5 Content-Type: multipart/mixed; boundary="------------090306090803050501080404" 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: 2008-10/txt/msg00033.txt.bz2 This is a multi-part message in MIME format. --------------090306090803050501080404 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-length: 0 --------------090306090803050501080404 Content-Type: text/plain; name="infcmd.txt" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="infcmd.txt" Content-length: 5906 This patch (#4), adds special handling for the "finish" command when executing in reverse. The new code can't actually be invoked until patch #5 is added, and so has no user visible effect. Tested under RHEL native with no change in results. 2008-09-30 Michael Snyder * breakpoint.h (breakpoint_silence): Export. * breakpoint.c (breakpoint_silence): New function. * infcmd.c (finish_command): Check for reverse exec direction. (finish_backward): New function, handle finish cmd in reverse. Index: breakpoint.c =================================================================== RCS file: /cvs/src/src/gdb/breakpoint.c,v retrieving revision 1.352 diff -u -p -r1.352 breakpoint.c --- breakpoint.c 16 Sep 2008 18:55:01 -0000 1.352 +++ breakpoint.c 30 Sep 2008 23:53:41 -0000 @@ -7741,6 +7741,13 @@ breakpoint_clear_ignore_counts (void) b->ignore_count = 0; } +void +breakpoint_silence (struct breakpoint *b) +{ + /* Silence the breakpoint. */ + b->silent = 1; +} + /* Command to set ignore-count of breakpoint N to COUNT. */ static void Index: breakpoint.h =================================================================== RCS file: /cvs/src/src/gdb/breakpoint.h,v retrieving revision 1.79 diff -u -p -r1.79 breakpoint.h --- breakpoint.h 22 Sep 2008 15:26:53 -0000 1.79 +++ breakpoint.h 30 Sep 2008 23:53:41 -0000 @@ -884,4 +884,7 @@ extern int breakpoints_always_inserted_m in our opinion won't ever trigger. */ extern void breakpoint_retire_moribund (void); +/* Tell a breakpoint to be quiet. */ +extern void breakpoint_silence (struct breakpoint *); + #endif /* !defined (BREAKPOINT_H) */ Index: infcmd.c =================================================================== RCS file: /cvs/src/src/gdb/infcmd.c,v retrieving revision 1.212 diff -u -p -r1.212 infcmd.c --- infcmd.c 22 Sep 2008 15:20:08 -0000 1.212 +++ infcmd.c 30 Sep 2008 23:53:41 -0000 @@ -1369,6 +1369,8 @@ finish_command_continuation_free_arg (vo /* "finish": Set a temporary breakpoint at the place the selected frame will return to, then continue. */ +static void finish_backwards (struct symbol *, struct thread_info *); + static void finish_command (char *arg, int from_tty) { @@ -1412,13 +1414,6 @@ finish_command (char *arg, int from_tty) clear_proceed_status (); - sal = find_pc_line (get_frame_pc (frame), 0); - sal.pc = get_frame_pc (frame); - - breakpoint = set_momentary_breakpoint (sal, get_frame_id (frame), bp_finish); - - old_chain = make_cleanup_delete_breakpoint (breakpoint); - /* Find the function we will return from. */ function = find_pc_function (get_frame_pc (get_selected_frame (NULL))); @@ -1427,10 +1422,29 @@ finish_command (char *arg, int from_tty) source. */ if (from_tty) { - printf_filtered (_("Run till exit from ")); + if (target_get_execution_direction () == EXEC_REVERSE) + printf_filtered ("Run back to call of "); + else + printf_filtered ("Run till exit from "); + print_stack_frame (get_selected_frame (NULL), 1, LOCATION); } + if (target_get_execution_direction () == EXEC_REVERSE) + { + /* Split off at this point. */ + finish_backwards (function, tp); + return; + } + + sal = find_pc_line (get_frame_pc (frame), 0); + sal.pc = get_frame_pc (frame); + + breakpoint = set_momentary_breakpoint (sal, get_frame_id (frame), + bp_finish); + + old_chain = make_cleanup_delete_breakpoint (breakpoint); + tp->proceed_to_finish = 1; /* We want stop_registers, please... */ make_cleanup_restore_integer (&suppress_stop_observer); suppress_stop_observer = 1; @@ -1514,6 +1528,66 @@ It stopped at a breakpoint that has sinc Type \"info stack\" or \"info registers\" for more information.\n")); } } + +static void +finish_backwards (struct symbol *function, struct thread_info *tp) +{ + struct symtab_and_line sal; + struct breakpoint *breakpoint; + struct cleanup *old_chain; + CORE_ADDR func_addr; + int back_up; + + if (find_pc_partial_function (get_frame_pc (get_current_frame ()), + NULL, &func_addr, NULL) == 0) + internal_error (__FILE__, __LINE__, + "Finish: couldn't find function."); + + sal = find_pc_line (func_addr, 0); + + /* TODO: Let's not worry about async until later. */ + + /* We don't need a return value. */ + tp->proceed_to_finish = 0; + /* Special case: if we're sitting at the function entry point, + then all we need to do is take a reverse singlestep. We + don't need to set a breakpoint, and indeed it would do us + no good to do so. + + Note that this can only happen at frame #0, since there's + no way that a function up the stack can have a return address + that's equal to its entry point. */ + + if (sal.pc != read_pc ()) + { + /* Set breakpoint and continue. */ + breakpoint = + set_momentary_breakpoint (sal, + get_frame_id (get_selected_frame (NULL)), + bp_breakpoint); + /* Tell the breakpoint to keep quiet. We won't be done + until we've done another reverse single-step. */ + breakpoint_silence (breakpoint); + old_chain = make_cleanup_delete_breakpoint (breakpoint); + proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 0); + /* We will be stopped when proceed returns. */ + back_up = bpstat_find_breakpoint (tp->stop_bpstat, breakpoint) != NULL; + do_cleanups (old_chain); + } + else + back_up = 1; + if (back_up) + { + /* If in fact we hit the step-resume breakpoint (and not + some other breakpoint), then we're almost there -- + we just need to back up by one more single-step. */ + /* (Kludgy way of letting wait_for_inferior know...) */ + tp->step_range_start = tp->step_range_end = 1; + proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 1); + } + return; +} + static void environment_info (char *var, int from_tty) --------------090306090803050501080404--