Summary:
The goal of this patch is two-fold. First, it fixes a use-after-free in
the construction of the llvm DWARFContext. This happened because the
construction code was throwing away the lldb DataExtractors it got while
reading the sections (unlike their llvm counterparts, these are also
responsible for memory ownership). In most cases this did not matter,
because the sections are just slices of the mmapped file data. But this
isn't the case for compressed elf sections, in which case the section is
decompressed into a heap buffer. A similar thing also happen with object
files which are loaded from process memory.
The second goal is to make it explicit which sections go into the llvm
DWARFContext -- any access to the sections through both DWARF parsers
carries a risk of parsing things twice, so it's better if this is a
conscious decision. Also, this avoids loading completely irrelevant
sections (e.g. .text). At present, the only section that needs to be
present in the llvm DWARFContext is the debug_line_str. Using it through
both APIs is not a problem, as there is no parsing involved.
The first goal is achieved by loading the sections through the existing
lldb DWARFContext APIs, which already do the caching. The second by
explicitly enumerating the sections we wish to load.
Reviewers: JDevlieghere, aprantl
Subscribers: lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D72917
These tests used "clang -mllvm -accel-tables=Dwarf" as a way to
guarantee that clang will emit the debug_names table. Unfortunately,
a change it clang made that insufficient (-gpubnames is required now
too), which rendered these tests ineffective. Since lldb automatically
falls back to the manual index, the tests didn't fail and this change
went largely unnoticed.
This patch updates the tests to really use debug_names (-gdwarf-5
-gpubnames) is the combination that works now, and it adds additional
checks to ensure the section is actually emitted.
Fortunately, no regressions crept in while these tests were disabled.
LLDB has three major testing strategies: unit tests, tests that exercise
the SB API though dotest.py and what we currently call lit tests. The
later is rather confusing as we're now using lit as the driver for all
three types of tests. As most of this grew organically, the directory
structure in the LLDB repository doesn't really make this clear.
The 'lit' tests are part of the root and among these tests there's a
Unit and Suite folder for the unit and dotest-tests. This layout makes
it impossible to run just the lit tests.
This patch changes the directory layout to match the 3 testing
strategies, each with their own directory and their own configuration
file. This means there are now 3 directories under lit with 3
corresponding targets:
- API (check-lldb-api): Test exercising the SB API.
- Shell (check-lldb-shell): Test exercising command line utilities.
- Unit (check-lldb-unit): Unit tests.
Finally, there's still the `check-lldb` target that runs all three test
suites.
Finally, this also renames the lit folder to `test` to match the LLVM
repository layout.
Differential revision: https://reviews.llvm.org/D68606
llvm-svn: 374184
Pavel Labath