As far as I can tell there are 2 parallel plugin mechanisms. opt -load=plugin does not work, and is ignored. opt -load-pass-plugin does work. The only user of PluginLoader appears to be bugpoint.
Ran into a use case where we had a MachO object file with a section symbol which did not have a section associated with it segfaults during linking. This patch aims to handle such cases gracefully and avoid the linker from crashing. --------- Co-authored-by: Ellis Hoag <ellis.sparky.hoag@gmail.com>
The really painful part of this PR was updating all the test files. I had some help from Gemini GLI there which did a pretty good job (got maybe 80% of the updates done). Fixes: #151015
Since equalsVariable runs a lot more times, we want to minimize the work
it
needs to do. Anything not dependent on the icfEqClass values should get
hoisted
out.
With this change, ICF runs ~1.7% faster when linking clang.
Benchmarking approach:
cbdr sample -b ~/extract-icf-time.sh ~/old/ld64.lld bin/ld64.lld
--timeout=300s | cbdr analyze -s 95
`extract-icf-time.sh` runs the clang link command with the `--icf=all
--time-trace` flags, then parses out the ICF duration from the resulting
time
trace using `jq`:
jq '{ICF: (.traceEvents[] | select(.name == "Fold Identical Code
Sections") | .dur)}'
Output:
</Users/jezng/extract-icf-time.sh ["/Users/jezng/old/ld64.lld"]>
</Users/jezng/extract-icf-time.sh ["bin/ld64.lld"]> difference (95% CI)
ICF 83678.207 ± 1502.778 82234.751 ± 1290.984 [ -2.0% .. -1.4%]
samples 208 225
In C++17, static constexpr members are implicitly inline, so they no longer require an out-of-line definition. Identified with readability-redundant-declaration.
This paves the way to make `--stack-first` the default. See: #151015
This is especially important for writing i32 values larger than 2gb which need to be encoded as negative SLEB vales in the binary. Without this change offsets over 2gb are wrongly encoded and cause validation errors. Fixes: https://github.com/emscripten-core/emscripten/issues/25706
Tested with `man lld/docs/ld.lld.1`
Update all uses of variadic `.Cases` to use the initializer list overload instead. I plan to mark variadic `.Cases` as deprecated in a followup PR. For more context, see https://github.com/llvm/llvm-project/pull/163117.