When -fgpu-rdc is used for linking relocatable objects, clang driver launches
clang-offload-bundler to extract a device relocatable object from each input
relocatable object file and passes the extracted files to lld. The input relocatable
object file could either come from HIP program or C++ program. The relocatable
object file from C++ program does not contain device relocatable objects, therefore
clang-offload-bundler extracts an empty file and passes it to lld. lld treates
empty file as linker script. When there is no object input file to lld, lld
will emit error:
target emulation unknown: -m or at least one .o file required
This patch adds "elf64_amdgpu" to lld so that lld always know the target
no matter whether there are object input files or not.
Reviewed by: Artem Belevich, Fangrui Song
Differential Revision: https://reviews.llvm.org/D138221
Follows up on commit cd5d5ce235 by
additionally ignoring relative paths ending in "lto-wrapper.exe" as
can be the case for GCC cross-compiled for Windows.
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D138065
Like D134013, but for COFF and Mach-O.
Also expand the ELF test a bit. I at first didn't realize that `getValue()` for
`-mllvm -foo=bar` would return `-foo=bar` instead of just `bar`, and so
I wrote the test to check if we indeed get this wrong. We don't, but
having the test for it seems nice, so I'm including it.
Differential Revision: https://reviews.llvm.org/D137971
Allowing incorrect version scripts is not a helpful default. Flip that
to help users find their bugs at build time rather than at run time.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D135402
Mach-O ld64 supports -w to suppress warnings. GNU ld 2.40 will support the
option as well (https://sourceware.org/bugzilla/show_bug.cgi?id=29654).
This feature has some small value. E.g. when analyzing a large executable with
relocation overflow issues, we may use --noinhibit-exec --emit-relocs to get an
output file with static relocations despite relocation overflow issues. -w can
significantly improve the link time as printing the massive warnings is slow.
Reviewed By: peter.smith
Differential Revision: https://reviews.llvm.org/D136569
A reference to __real_foo should trigger archive extraction of the input file that defines foo, otherwise a link using --wrap=foo might fail to link with an undefined reference to foo.
This matches bfd linker behaviour.
Differential Revision: https://reviews.llvm.org/D135897
This reverts commit 096f93e73d.
Revert "[Libomptarget] Make the plugins ingore undefined exported symbols"
This reverts commit 3f62314c23.
Revert "[LLD] Enable --no-undefined-version by default."
This reverts commit 7ec8b0d162.
Three commits are reverted because of the current omp build fail
with GNU ld. See discussion here: https://reviews.llvm.org/rG096f93e73dc3
Allowing incorrect version scripts is not a helpful default. Flip that
to help users find their bugs at build time rather than at run time.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D135402
Add LLVM_LIBRARY_VISIBILITY to remove unneeded GOT and unique_ptr
indirection. We can move other global variables into ctx without
indirection concern. In the long term we may consider passing Ctx
as a parameter to various functions and eliminate global state as
much as possible and then remove `Ctx::reset`.
`config` has 1000+ uses so we try to avoid changing `config->foo`. Define a
wrapper with LLVM_LIBRARY_VISIBILITY to remove unneeded GOT and unique_ptr
indirection.
My x86-64 lld executable is 11+KiB smaller.
Symbol::replace intends to overwrite a few fields (mostly Elf{32,64}_Sym
fields), but the implementation copies all fields then restores some old fields.
This is error-prone and wasteful. Add Symbol::overwrite to copy just the
needed fields and add other overwrite member functions to copy the extra
fields.
They may modify thinlto optimization.
This patch only extends support for `-mllvm`. There is another way to
pass llvm flags, `-plugin-opt`, but its processing is different and will
be provided in a subsequent patch.
Differential Revision: https://reviews.llvm.org/D134013
`clang -gz=zstd a.o` passes this option to the linker. This option compresses output
debug sections with zstd and sets ch_type to ELFCOMPRESS_ZSTD. As of today, very
few DWARF consumers recognize ELFCOMPRESS_ZSTD.
Use the llvm::zstd::compress API with level llvm::zstd::DefaultCompression (5),
which we may tune after we have more experience with zstd output.
zstd has built-in parallel compression support (so we don't need to do D117853
for zlib), which is not leveraged yet.
Reviewed By: peter.smith
Differential Revision: https://reviews.llvm.org/D133548
This change renames this method match its original name and the name
used in the wasm linker.
Back in d8f8abbd4a the ELF SymbolTable
method `getSymbols()` was replaced with `forEachSymbol`.
Then in a2fc964417 `forEachSymbol` was
replaced with a `llvm::iterator_range`.
Then in e9262edf0d we came full circle
and the `llvm::iterator_range` was replaced with a `symbols()` accessor
that was identical the original `getSymbols()`.
`getSymbols` also matches the name used elsewhere in the ELF linker as
well as in both COFF and wasm backend (e.g. `InputFiles.h` and
`SyntheticSections.h`)
Differential Revision: https://reviews.llvm.org/D130787
This was recently introduced in GNU linkers and it makes sense for
ld.lld to have the same support. This implementation omits checking if
the input string is valid json to reduce size bloat.
Differential Revision: https://reviews.llvm.org/D131439
This implements the last step of
https://discourse.llvm.org/t/parallel-input-file-parsing/60164 for the ELF port.
For an ELF object file, we previously did: parse, (parallel) initializeLocalSymbols, (parallel) postParseObjectFile.
Now we do: parse, (parallel) initSectionsAndLocalSyms, (parallel) postParseObjectFile.
initSectionsAndLocalSyms does most of input section initialization.
The sequential `parse` does SHT_ARM_ATTRIBUTES/SHT_RISCV_ATTRIBUTES/SHT_GROUP initialization for now.
Performance linking some programs with --threads=8 (glibc 2.33 malloc and mimalloc):
* clang: 1.05x as fast with glibc malloc, 1.03x as fast with mimalloc
* chrome: 1.04x as fast with glibc malloc, 1.03x as fast with mimalloc
* internal search program: 1.08x as fast with glibc malloc, 1.05x as fast with mimalloc
Reviewed By: peter.smith
Differential Revision: https://reviews.llvm.org/D130810
I went over the output of the following mess of a command:
`(ulimit -m 2000000; ulimit -v 2000000; git ls-files -z | parallel --xargs -0 cat | aspell list --mode=none --ignore-case | grep -E '^[A-Za-z][a-z]*$' | sort | uniq -c | sort -n | grep -vE '.{25}' | aspell pipe -W3 | grep : | cut -d' ' -f2 | less)`
and proceeded to spend a few days looking at it to find probable typos
and fixed a few hundred of them in all of the llvm project (note, the
ones I found are not anywhere near all of them, but it seems like a
good start).
Differential Revision: https://reviews.llvm.org/D130982
inputSections temporarily contains EhInputSection objects mainly for
combineEhSections. Place EhInputSection objects into a new vector
ehInputSections instead of inputSections.
* Refactor compression namespaces across the project, making way for a possible
introduction of alternatives to zlib compression.
Changes are as follows:
* Relocate the `llvm::zlib` namespace to `llvm::compression::zlib`.
Reviewed By: MaskRay, leonardchan, phosek
Differential Revision: https://reviews.llvm.org/D128953
Allows specific “temps” to be saved, instead of the current all-or-nothing nature of --save-temps. Multiple of these “temps” can be saved by specifying the argument multiple times.
Differential Revision: https://reviews.llvm.org/D127778
`--time-trace=foo` has the same behavior as `--time-trace --time-trace-file=<file>`
had previously.
Also, for mac, make --time-trace-granularity *not* imply --time-trace, to match
behavior of the ELF port.
Differential Revision: https://reviews.llvm.org/D128451
Allows ThinLTO indices to be written to disk on-the-fly/as-part-of “normal” linker execution. Previously ThinLTO indices could be written via --thinlto-index-only but that would cause the linker to exit early. For MLGO specifically, this enables saving the ThinLTO index files without having to restart the linker to collect data only available at later stages (i.e. output of --save-temps) of the linker's execution.
Note, this option does not currently work with:
--thinlto-object-suffix-replace, as this is intended to be used to consume minimized IR bitcode files while --thinlto-emit-index-files is intended to be run together with InProcessThinLTO (which cannot parse minimized IR).
--thinlto-prefix-replace support is left unimplemented but can be implemented if needed
Differential Revision: https://reviews.llvm.org/D127777
LTO code may end up mixing bitcode files from various sources varying in
their use of opaque pointer types. The current strategy to decide
between opaque / typed pointers upon the first bitcode file loaded does
not work here, since we could be loading a non-opaque bitcode file first
and would then be unable to load any files with opaque pointer types
later.
So for LTO this:
- Adds an `lto::Config::OpaquePointer` option and enforces an upfront
decision between the two modes.
- Adds `-opaque-pointers`/`-no-opaque-pointers` options to the gold
plugin; disabled by default.
- `--opaque-pointers`/`--no-opaque-pointers` options with
`-plugin-opt=-opaque-pointers`/`-plugin-opt=-no-opaque-pointers`
aliases to lld; disabled by default.
- Adds an `-lto-opaque-pointers` option to the `llvm-lto2` tool.
- Changes the clang driver to pass `-plugin-opt=-opaque-pointers` to
the linker in LTO modes when clang was configured with opaque
pointers enabled by default.
This fixes https://github.com/llvm/llvm-project/issues/55377
Differential Revision: https://reviews.llvm.org/D125847
This flag is added by clang::driver::tools::addLTOOptions() and was causing
errors for me when building the llvm-test-suite repository with LTO and
-DTEST_SUITE_COLLECT_STATS=ON. This replaces the --stats-file= option
added in 1c04b52b25 since the flag is only
used for LTO and should therefore be in the -plugin-opt= namespace.
Additionally, this commit fixes the `REQUIRES: asserts` that was added in
948d05324a: the feature was never defined in
the lld test suite so it effectively disabled the test.
Reviewed By: MaskRay, MTC
Differential Revision: https://reviews.llvm.org/D124105
