Reapply "[NFC][DebugInfo][DWARF] Create new low-level dwarf library (#…
(#145959)
This reapplies cbf781f0bdf2f680abbe784faedeefd6f84c246e, with fixes for
the shared-library build and the unconventional sanitizer-runtime build.
Original Description:
This is the culmination of a series of changes described in [1].
Although somewhat large by line count, it is almost entirely mechanical,
creating a new library in DebugInfo/DWARF/LowLevel. This new library has
very minimal dependencies, allowing it to be used from more places than
the normal DebugInfo/DWARF library--in particular from MC.
1.
https://discourse.llvm.org/t/rfc-debuginfo-dwarf-refactor-into-to-lower-and-higher-level-libraries/86665/2
This is the culmination of a series of changes described in [1].
Although somewhat large by line count, it is almost entirely mechanical,
creating a new library in DebugInfo/DWARF/LowLevel. This new library has
very minimal dependencies, allowing it to be used from more places than
the normal DebugInfo/DWARF library--in particular from MC.
I am happy to put it in another location, or to structure it differently
if that makes sense. Some have suggested in BinaryFormat, but it is not
a great fit there. But if that makes more sense to the reviewers, I can
do that.
Another possibility would be to use pass-through headers to allow
clients who don't care to depend only on DebugInfo/DWARF. This would be
a much less invasive change, and perhaps easier for clients. But also a
system that hides details.
Either way, I'm open.
1.
https://discourse.llvm.org/t/rfc-debuginfo-dwarf-refactor-into-to-lower-and-higher-level-libraries/86665/2
Use SymbolStringPtr for Symbol names in LinkGraph. This reduces string interning
on the boundary between JITLink and ORC, and allows pointer comparisons (rather
than string comparisons) between Symbol names. This should improve the
performance and readability of code that bridges between JITLink and ORC (e.g.
ObjectLinkingLayer and ObjectLinkingLayer::Plugins).
To enable use of SymbolStringPtr a std::shared_ptr<SymbolStringPool> is added to
LinkGraph and threaded through to its construction sites in LLVM and Bolt. All
LinkGraphs that are to have symbol names compared by pointer equality must point
to the same SymbolStringPool instance, which in ORC sessions should be the pool
attached to the ExecutionSession.
---------
Co-authored-by: Lang Hames <lhames@gmail.com>
Running into an error with removing DWP where the assertion
`RelaxAllView &&
"RegisterMCTargetOptionsFlags not created."'` failed. This is a result
of DWP bringing the mc::RegisterMCTargetOptionsFlags option in, and the
option being removed with DWP. The need for this option didn't
originally exist because we didn't use MC in DWARFRewriter, but we
switched to using DWARFStreamer which needed the option.
https://reviews.llvm.org/D75579https://reviews.llvm.org/D106417
Followup to the splitting of processUnitDIE, moves code that accesses
common resource to be outside of the function that will be parallelized.
Followup to #99957
Refactors legacy ranges writers to create a writer for each instance of
a DWO file.
We now write out everything into .debug_ranges after the all the DWO
files are processed. This also changes the order that ranges is written
out in, as before we wrote out while in the main CU processing loop and
we now iterate through the CU buckets created by partitionCUs, after the
main processing loop.
This patch fixes:
bolt/lib/Rewrite/DWARFRewriter.cpp:187:18: error: private field
'Rewriter' is not used [-Werror,-Wunused-private-field]
Note that:
commit 61df854d4c4d5f955693394d57f09b9fcd35be67
Author: Sayhaan Siddiqui <49014204+sayhaan@users.noreply.github.com>
Date: Mon Jun 10 10:46:20 2024 -0700
removed the last use of Rewriter.
Type unit DIE generated by clang contains DW_AT_comp_dir/DW_AT_dwo_name.
This was added to clang to help LLDB to figure out where type unit come
from when accessing an entry in a .debug_names accelerator table and
type units in .dwp file.
When BOLT writes out .dwo files it changes the name of them. User can
also specify directory of where they can be written out. Added support
to BOLT to update those attributes.
I'm planning to remove StringRef::equals in favor of
StringRef::operator==.
- StringRef::operator==/!= outnumber StringRef::equals by a factor of
276 under llvm-project/ in terms of their usage.
- The elimination of StringRef::equals brings StringRef closer to
std::string_view, which has operator== but not equals.
- S == "foo" is more readable than S.equals("foo"), especially for
!Long.Expression.equals("str") vs Long.Expression != "str".
We need to update DW_AT_comp_dir/DW_AT_dwo_name TU in the
.debug_info.dwo section so that the path is correct. Refactored helper
functions to make it easier for next step.
For DWARF5 BOLT was not retreiving address and instead was setting an
index.
Changed so that an address is used, and added DWARF4 test because it was
missing.
commit 43a2ec483fe08064b53a6293682e9bab97df61a0
Author: Jonas Devlieghere <jonas@devlieghere.com>
Date: Tue Mar 19 08:30:47 2024 -0700
removed parameter Translator from the constructor of DwarfStreamer.
This patch fixes the build by updating the constructor of DIEStreamer
accordingly.
DWARF5 spec supports the .debug_names acceleration table. This is the
formalized version of combination of gdb-index/pubnames/types. Added
implementation of it to BOLT. It supports both monolothic and split
dwarf, with and without Type Units. It does not include parent indices.
This will be in followup PR. Unlike LLVM output this will put all the
CUs and TUs into one Module.
Make core BOLT functionality more friendly to being used as a
library instead of in our standalone driver llvm-bolt. To
accomplish this, we augment BinaryContext with journaling streams
that are to be used by most BOLT code whenever something needs to
be logged to the screen. Users of the library can decide if logs
should be printed to a file, no file or to the screen, as
before. To illustrate this, this patch adds a new option
`--log-file` that allows the user to redirect BOLT logging to a
file on disk or completely hide it by using
`--log-file=/dev/null`. Future BOLT code should now use
`BinaryContext::outs()` for printing important messages instead of
`llvm::outs()`. A new test log.test enforces this by verifying that
no strings are print to screen once the `--log-file` option is
used.
In previous patches we also added a new BOLTError class to report
common and fatal errors, so code shouldn't call exit(1) now. To
easily handle problems as before (by quitting with exit(1)),
callers can now use
`BinaryContext::logBOLTErrorsAndQuitOnFatal(Error)` whenever code
needs to deal with BOLT errors. To test this, we have fatal.s
that checks we are correctly quitting and printing a fatal error
to the screen.
Because this is a significant change by itself, not all code was
yet ported. Code from Profiler libs (DataAggregator and friends)
still print errors directly to screen.
Co-authored-by: Rafael Auler <rafaelauler@fb.com>
Test Plan: NFC
Added an --comp-dir-override option that overrides DW_AT_comp_dir in the
unit die. This allows for llvm-bolt to be invoked from any category and
still find .dwo files.
This patch creates DWARFLinkerBase library, places DWARFLinker code into
DWARFLinker\Classic, places DWARFLinkerParallel into DWARFLinker\Parallel.
updates BOLT to use new library. This patch is NFC.
