[PATCH v3 0/5] Fix lost events, and handle multiple step-overs.

Pedro Alves
2014-03-07T01:10:45Z

Here's v3. This version mainly addresses Doug's review of patch 2 of
v2. As the rest of the series would no longer apply and one patch
needed a minor corresponding tweak, I'm resending it all.

v2 was here:

https://sourceware.org/ml/gdb-patches/2014-03/msg00128.html

v1 was here:

https://sourceware.org/ml/gdb-patches/2014-02/msg00761.html.

What remains is related to GDB losing events - breakpoints and
watchpoints - in some situations, about teaching GDB that it might
need to step over breakpoints in multiple threads.

One nice side effect of patch #2 is that GDB no longer removes/inserts
_all_ breakpoints when stepping over one. GDB after that only removes
the breakpoint being stepped over. This eliminates a lot of z0/Z0 RSP
traffic if you have a lot of breakpoints, and have a conditional or
thread-specific breakpoint constantly triggering and not causing a
user-visible stop.

This changes heavily core run control code, which affects software
single-step targets too. For more comfortable development and
testing, I actually hacked on this against my software single-step on
x86 branch first.

Tested on x86_64 Fedora 17, against pristine mainline, and against a
series that implements software single-step on x86-64.

For convenience, you can find this series at:

git@github.com:palves/gdb.git fix_a_bunch_of_run_control_bugs_v3

and with software single-step on x86 on top:

git@github.com:palves/gdb.git fix_a_bunch_of_run_control_bugs_v3_sss

In absence of barring comments, I plan to push this in soon.

Changes in v3:

- Polish patch for PR breakpoints/7143, in response to Doug's review.

Changes in v2:

- Two patches of v1 applied.

- Order of some of the remaining patches changed.

- Bugs that exposed were fixed.

- One test moved to a different patch and got extended to cover
another scenario gdb was mishandling and this series fixes.

- Yao's review comments to v1's tests (to date) are addressed.

- Software single-step breakpoints are not longer converted to real
breakpoints.

Pedro Alves (5):
Fix missing breakpoint/watchpoint hits, eliminate deferred_step_ptid.
PR breakpoints/7143 - Watchpoint does not trigger when first set
Fix for even more missed events; eliminate thread-hop code.
Handle multiple step-overs.
Make signal-while-stepping-over-bp-other-thread.exp run against
remote targets too.

gdb/breakpoint.c | 25 +-
gdb/breakpoint.h | 13 +
gdb/inferior.h | 6 +
gdb/infrun.c | 765 ++++++++++-----------
gdb/testsuite/gdb.base/watchpoint.exp | 13 +-
gdb/testsuite/gdb.cp/annota2.exp | 3 -
gdb/testsuite/gdb.cp/annota3.exp | 3 -
gdb/testsuite/gdb.threads/multiple-step-overs.c | 105 +++
gdb/testsuite/gdb.threads/multiple-step-overs.exp | 80 +++
.../signal-while-stepping-over-bp-other-thread.c | 2 +
.../signal-while-stepping-over-bp-other-thread.exp | 16 +-
.../gdb.threads/step-over-lands-on-breakpoint.c | 65 ++
.../gdb.threads/step-over-lands-on-breakpoint.exp | 62 ++
.../gdb.threads/step-over-trips-on-watchpoint.c | 67 ++
.../gdb.threads/step-over-trips-on-watchpoint.exp | 90 +++
15 files changed, 877 insertions(+), 438 deletions(-)
create mode 100644 gdb/testsuite/gdb.threads/multiple-step-overs.c
create mode 100644 gdb/testsuite/gdb.threads/multiple-step-overs.exp
create mode 100644 gdb/testsuite/gdb.threads/step-over-lands-on-breakpoint.c
create mode 100644 gdb/testsuite/gdb.threads/step-over-lands-on-breakpoint.exp
create mode 100644 gdb/testsuite/gdb.threads/step-over-trips-on-watchpoint.c
create mode 100644 gdb/testsuite/gdb.threads/step-over-trips-on-watchpoint.exp

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1.7.11.7