From ef5cf84e219f3d26788d55e01ca7ebfb5b39406d Mon Sep 17 00:00:00 2001 From: Michael Snyder Date: Tue, 26 Jun 2001 00:26:42 +0000 Subject: [PATCH] 2001-06-25 Michael Snyder * infrun.c: Eliminate the "thread_step_needed" state variable, and replace it with a relatively simple test in resume. (resume): Replace thread_step_needed logic with a test for stepping, breakpoint_here_p and breakpoints_inserted. Move CANNOT_STEP_BREAKPOINT logic to after thread_step logic. (proceed): Discard thread_step_needed logic. (wait_for_inferior, fetch_inferior_event, handle_inferior_event): Discard thread_step_needed logic. --- gdb/ChangeLog | 11 +++++ gdb/infrun.c | 122 ++++++++++---------------------------------------- 2 files changed, 35 insertions(+), 98 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 1c245287f0b..c7cc4b472a1 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,14 @@ +2001-06-25 Michael Snyder + + * infrun.c: Eliminate the "thread_step_needed" state variable, + and replace it with a relatively simple test in resume. + (resume): Replace thread_step_needed logic with a test for + stepping, breakpoint_here_p and breakpoints_inserted. + Move CANNOT_STEP_BREAKPOINT logic to after thread_step logic. + (proceed): Discard thread_step_needed logic. + (wait_for_inferior, fetch_inferior_event, handle_inferior_event): + Discard thread_step_needed logic. + 2001-06-24 Fernando Nasser * remote-rdi.c (arm_rdi_wait): Fix return type in prototype. diff --git a/gdb/infrun.c b/gdb/infrun.c index ba623338438..a500e97948a 100644 --- a/gdb/infrun.c +++ b/gdb/infrun.c @@ -110,31 +110,6 @@ static ptid_t previous_inferior_ptid; static int may_follow_exec = MAY_FOLLOW_EXEC; -/* resume and wait_for_inferior use this to ensure that when - stepping over a hit breakpoint in a threaded application - only the thread that hit the breakpoint is stepped and the - other threads don't continue. This prevents having another - thread run past the breakpoint while it is temporarily - removed. - - This is not thread-specific, so it isn't saved as part of - the infrun state. - - Versions of gdb which don't use the "step == this thread steps - and others continue" model but instead use the "step == this - thread steps and others wait" shouldn't do this. */ - -static int thread_step_needed = 0; - -/* This is true if thread_step_needed should actually be used. At - present this is only true for HP-UX native. */ - -#ifndef USE_THREAD_STEP_NEEDED -#define USE_THREAD_STEP_NEEDED (0) -#endif - -static int use_thread_step_needed = USE_THREAD_STEP_NEEDED; - /* GET_LONGJMP_TARGET returns the PC at which longjmp() will resume the program. It needs to examine the jmp_buf argument and extract the PC from it. The return value is non-zero on success, zero otherwise. */ @@ -821,13 +796,8 @@ resume (int step, enum target_signal sig) struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0); QUIT; -#ifdef CANNOT_STEP_BREAKPOINT - /* Most targets can step a breakpoint instruction, thus executing it - normally. But if this one cannot, just continue and we will hit - it anyway. */ - if (step && breakpoints_inserted && breakpoint_here_p (read_pc ())) - step = 0; -#endif + /* FIXME: calling breakpoint_here_p (read_pc ()) three times! */ + /* Some targets (e.g. Solaris x86) have a kernel bug when stepping over an instruction that causes a page fault without triggering @@ -910,41 +880,34 @@ resume (int step, enum target_signal sig) { ptid_t resume_ptid; - if (use_thread_step_needed && thread_step_needed) + resume_ptid = RESUME_ALL; /* Default */ + + if ((step || singlestep_breakpoints_inserted_p) && + !breakpoints_inserted && breakpoint_here_p (read_pc ())) { - /* We stopped on a BPT instruction; - don't continue other threads and - just step this thread. */ - thread_step_needed = 0; + /* Stepping past a breakpoint without inserting breakpoints. + Make sure only the current thread gets to step, so that + other threads don't sneak past breakpoints while they are + not inserted. */ - if (!breakpoint_here_p (read_pc ())) - { - /* Breakpoint deleted: ok to do regular resume - where all the threads either step or continue. */ - resume_ptid = RESUME_ALL; - } - else - { - if (!step) - { - warning ("Internal error, changing continue to step."); - remove_breakpoints (); - breakpoints_inserted = 0; - trap_expected = 1; - step = 1; - } - resume_ptid = inferior_ptid; - } + resume_ptid = inferior_ptid; } - else + + if ((scheduler_mode == schedlock_on) || + (scheduler_mode == schedlock_step && + (step || singlestep_breakpoints_inserted_p))) { - /* Vanilla resume. */ - if ((scheduler_mode == schedlock_on) || - (scheduler_mode == schedlock_step && step != 0)) + /* User-settable 'scheduler' mode requires solo thread resume. */ resume_ptid = inferior_ptid; - else - resume_ptid = RESUME_ALL; } + +#ifdef CANNOT_STEP_BREAKPOINT + /* Most targets can step a breakpoint instruction, thus executing it + normally. But if this one cannot, just continue and we will hit + it anyway. */ + if (step && breakpoints_inserted && breakpoint_here_p (read_pc ())) + step = 0; +#endif target_resume (resume_ptid, step, sig); } @@ -1019,16 +982,6 @@ proceed (CORE_ADDR addr, enum target_signal siggnal, int step) else { write_pc (addr); - - /* New address; we don't need to single-step a thread - over a breakpoint we just hit, 'cause we aren't - continuing from there. - - It's not worth worrying about the case where a user - asks for a "jump" at the current PC--if they get the - hiccup of re-hiting a hit breakpoint, what else do - they expect? */ - thread_step_needed = 0; } #ifdef PREPARE_TO_PROCEED @@ -1046,7 +999,6 @@ proceed (CORE_ADDR addr, enum target_signal siggnal, int step) if (PREPARE_TO_PROCEED (1) && breakpoint_here_p (read_pc ())) { oneproc = 1; - thread_step_needed = 1; } #endif /* PREPARE_TO_PROCEED */ @@ -1287,8 +1239,6 @@ wait_for_inferior (void) /* Fill in with reasonable starting values. */ init_execution_control_state (ecs); - thread_step_needed = 0; - /* We'll update this if & when we switch to a new thread. */ previous_inferior_ptid = inferior_ptid; @@ -1347,8 +1297,6 @@ fetch_inferior_event (void *client_data) /* Fill in with reasonable starting values. */ init_execution_control_state (async_ecs); - thread_step_needed = 0; - /* We'll update this if & when we switch to a new thread. */ previous_inferior_ptid = inferior_ptid; @@ -1498,11 +1446,6 @@ handle_inferior_event (struct execution_control_state *ecs) /* Fall thru to the normal_state case. */ case infwait_normal_state: - /* Since we've done a wait, we have a new event. Don't - carry over any expectations about needing to step over a - breakpoint. */ - thread_step_needed = 0; - /* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event is serviced in this loop, below. */ if (ecs->enable_hw_watchpoints_after_wait) @@ -1934,30 +1877,14 @@ handle_inferior_event (struct execution_control_state *ecs) context_switch (ecs); ecs->waiton_ptid = ecs->ptid; ecs->wp = &(ecs->ws); - thread_step_needed = 1; ecs->another_trap = 1; - /* keep_stepping will call resume, and the - combination of "thread_step_needed" and - "ecs->another_trap" will cause resume to - solo-step the thread. The subsequent trap - event will be handled like any other singlestep - event. */ - ecs->infwait_state = infwait_thread_hop_state; keep_going (ecs); registers_changed (); return; } } - else - { - /* This breakpoint matches--either it is the right - thread or it's a generic breakpoint for all threads. - Remember that we'll need to step just _this_ thread - on any following user continuation! */ - thread_step_needed = 1; - } } } else @@ -2413,7 +2340,6 @@ handle_inferior_event (struct execution_control_state *ecs) case BPSTAT_WHAT_SINGLE: if (breakpoints_inserted) { - thread_step_needed = 1; remove_breakpoints (); } breakpoints_inserted = 0; -- 2.30.2