From a57b62deef37c7f2ec31bca3bf9173a6206bfb9b Mon Sep 17 00:00:00 2001 From: Venkata Ramanaiah Nalamothu Date: Thu, 2 Jun 2022 23:19:30 +0530 Subject: [lldb] Fix thread step until to not set breakpoint(s) on incorrect line numbers The requirements for "thread until " are: a) If any code contributed by or the nearest subsequent of is executed before leaving the function, stop b) If you end up leaving the function w/o triggering (a), then stop In case of (a), since the may have multiple entries in the line table and the compiler might have scheduled/moved the relevant code across, and the lldb does not know the control flow, set breakpoints on all the line table entries of best match of i.e. exact or the nearest subsequent line. Along with the above, currently, CommandObjectThreadUntil is also setting the breakpoints on all the subsequent line numbers after the best match and this latter part is wrong. This issue is discussed at http://lists.llvm.org/pipermail/lldb-dev/2018-August/013979.html. In fact, currently `TestStepUntil.py` is not actually testing step until scenarios and `test_missing_one` test fails without this patch if tests are made to run. Fixed the test as well. Reviewed By: jingham Differential Revision: https://reviews.llvm.org/D50304 --- lldb/source/Commands/CommandObjectThread.cpp | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'lldb/source/Commands/CommandObjectThread.cpp') diff --git a/lldb/source/Commands/CommandObjectThread.cpp b/lldb/source/Commands/CommandObjectThread.cpp index 037bbafdf894..9396c3615497 100644 --- a/lldb/source/Commands/CommandObjectThread.cpp +++ b/lldb/source/Commands/CommandObjectThread.cpp @@ -1033,11 +1033,21 @@ protected: line_table->FindLineEntryByAddress(fun_end_addr, function_start, &end_ptr); + // Since not all source lines will contribute code, check if we are + // setting the breakpoint on the exact line number or the nearest + // subsequent line number and set breakpoints at all the line table + // entries of the chosen line number (exact or nearest subsequent). for (uint32_t line_number : line_numbers) { + LineEntry line_entry; + bool exact = false; uint32_t start_idx_ptr = index_ptr; + start_idx_ptr = sc.comp_unit->FindLineEntry( + index_ptr, line_number, nullptr, exact, &line_entry); + if (start_idx_ptr != UINT32_MAX) + line_number = line_entry.line; + exact = true; + start_idx_ptr = index_ptr; while (start_idx_ptr <= end_ptr) { - LineEntry line_entry; - const bool exact = false; start_idx_ptr = sc.comp_unit->FindLineEntry( start_idx_ptr, line_number, nullptr, exact, &line_entry); if (start_idx_ptr == UINT32_MAX) -- cgit v1.2.3