The computation of 'Thread::IsVirtualStep" was wrong - it called being
at the bottom of a virtual call stack a "virtual step" but that is
actually when you've gotten to concrete code and need to step for real.
I also added a test for this.
This fixes the two test suite failures that I missed in the PR:
https://github.com/llvm/llvm-project/pull/112939
One was a poorly written test case - it assumed that on connect to a
gdb-remote with a running process, lldb MUST have fetched all the frame
0 registers. In fact, there's no need for it to do so (as the CallSite
patch showed...) and if we don't need to we shouldn't. So I fixed the
test to only expect a `g` packet AFTER calling read_registers.
The other was a place where some code had used 0 when it meant
LLDB_INVALID_LINE_NUMBER, which I had fixed but missed one place where
it was still compared to 0.
…ne stepping (#112939)"
This was breaking some gdb-remote packet counting tests on the bots. I
can't see how this patch could cause that breakage, but I'm reverting to
figure that out.
This reverts commit f14743794587db102c6d1b20f9c87a1ac20decfd.
Previously lldb didn't support setting breakpoints on call site
locations. This patch adds that ability.
It would be very slow if we did this by searching all the debug
information for every inlined subroutine record looking for a call-site
match, so I added one restriction to the call-site support. This change
will find all call sites for functions that also supply at least one
line to the regular line table. That way we can use the fact that the
line table search will move the location to that subsequent line (but
only within the same function). When we find an actually moved source
line match, we can search in the function that contained that line table
entry for the call-site, and set the breakpoint location back to that.
When I started writing tests for this new ability, it quickly became
obvious that our support for virtual inline stepping was pretty buggy.
We didn't print the right file & line number for the breakpoint, and we
didn't set the position in the "virtual inlined stack" correctly when we
hit the breakpoint. We also didn't step through the inlined frames
correctly. There was code to try to detect the right inlined stack
position, but it had been refactored a while back with the comment that
it was super confusing and the refactor was supposed to make it clearer,
but the refactor didn't work either.
That code was made much clearer by abstracting the job of "handling the
stack readjustment" to the various StopInfo's. Previously, there was a
big (and buggy) switch over stop info's. Moving the responsibility to
the stop info made this code much easier to reason about.
We also had no tests for virtual inlined stepping (our inlined stepping
test was actually written specifically to avoid the formation of a
virtual inlined stack... So I also added tests for that along with the
tests for setting the call-site breakpoints.
Summary:
TestInlineStepping tests LLDB's ability to step in the presence of
inline frames. The testcase source has a number of functions and some
of them are marked `always_inline`.
The test is built around the assumption that the inline function will
be fully represented once inlined, but this is not true with the
current arm64 code generation. For example:
void caller() {
always_inline_function(); // Step here
}
When stppeing into `caller()` above, you might immediatly end up in
the inlines frame for `always_inline_function()`, because there might
literally be no code associated with `caller()` itself.
This patch hacks around the issue by adding an `asm volatile("nop")`
on some lines with inlined calls where we expect to be able to
step. Like so:
void caller() {
asm volatile("nop"); always_inline_function(); // Step here
}
This guarantees there is always going to be one instruction for this
line in the caller.
Reviewers: labath, jingham
Subscribers: kristof.beyls, danielkiss, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D76406
Summary: Moves lldbsuite tests to lldb/test/API.
This is a largely mechanical change, moved with the following steps:
```
rm lldb/test/API/testcases
mkdir -p lldb/test/API/{test_runner/test,tools/lldb-{server,vscode}}
mv lldb/packages/Python/lldbsuite/test/test_runner/test lldb/test/API/test_runner
for d in $(find lldb/packages/Python/lldbsuite/test/* -maxdepth 0 -type d | egrep -v "make|plugins|test_runner|tools"); do mv $d lldb/test/API; done
for d in $(find lldb/packages/Python/lldbsuite/test/tools/lldb-vscode -maxdepth 1 -mindepth 1 | grep -v ".py"); do mv $d lldb/test/API/tools/lldb-vscode; done
for d in $(find lldb/packages/Python/lldbsuite/test/tools/lldb-server -maxdepth 1 -mindepth 1 | egrep -v "gdbremote_testcase.py|lldbgdbserverutils.py|socket_packet_pump.py"); do mv $d lldb/test/API/tools/lldb-server; done
```
lldb/packages/Python/lldbsuite/__init__.py and lldb/test/API/lit.cfg.py were also updated with the new directory structure.
Reviewers: labath, JDevlieghere
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D71151
