93e45a69dd
lldb will change how it reports stop reasons around breakpoints in the near future. I landed an earlier version of this change and noticed debuginfo test failures on the CI bots due to the changes. I'm addressing the issues found by CI at https://github.com/llvm/llvm-project/pull/105594 and will re-land once I've done all of them. Currently, when lldb stops at a breakpoint instruction -- but has not yet executed the instruction -- it will overwrite the thread's Stop Reason with "breakpoint-hit". This caused bugs when the original stop reason was important to the user - for instance, a watchpoint on an AArch64 system where we have to instruction-step past the watchpoint to find the new value. Normally we would instruction step, fetch the new value, then report the user that a watchpoint has been hit with the old and new values. But if the instruction after this access is a breakpoint site, we overwrite the "watchpoint hit" stop reason (and related actions) with "breakpoint hit". dexter sets breakpoints on all source lines, then steps line-to-line, hitting the breakpoints. But with this new behavior, we see two steps per source line: The first step gets us to the start of the next line, with a "step completed" stop reason. Then we step again and we execute the breakpoint instruction, stop with the pc the same, and report "breakpoint hit". Now we can step a second time and move past the breakpoint. I've changed the `step` method in LLDB.py to check if we step to a breakpoint site but have a "step completed" stop reason -- in which case we have this new breakpoint behavior, and we need to step a second time to actually hit the breakpoint like the debuginfo tests expect.
-*- rst -*-
This is a collection of tests to check debugging information generated by
compiler. This test suite can be checked out inside clang/test folder. This
will enable 'make test' for clang to pick up these tests.
Some tests (in the 'llgdb-tests' directory) are written with debugger
commands and checks for the intended debugger output in the source file,
using DEBUGGER: and CHECK: as prefixes respectively.
For example::
define i32 @f1(i32 %i) nounwind ssp {
; DEBUGGER: break f1
; DEBUGGER: r
; DEBUGGER: p i
; CHECK: $1 = 42
entry:
}
is a testcase where the debugger is asked to break at function 'f1' and
print value of argument 'i'. The expected value of 'i' is 42 in this case.
Other tests are written for use with the 'Dexter' tool (in the 'dexter-tests'
and 'dexter' directories respectively). These use a domain specific language
in comments to describe the intended debugger experience in a more abstract
way than debugger commands. This allows for testing integration across
multiple debuggers from one input language.
For example::
void __attribute__((noinline, optnone)) bar(int *test) {}
int main() {
int test;
test = 23;
bar(&test); // DexLabel('before_bar')
return test; // DexLabel('after_bar')
}
// DexExpectWatchValue('test', '23', on_line='before_bar')
// DexExpectWatchValue('test', '23', on_line='after_bar')
Labels two lines with the names 'before_bar' and 'after_bar', and records that
the 'test' variable is expected to have the value 23 on both of them.