forked from OSchip/llvm-project
86c8f395ae
Fixes PR51578 in practice. Currently there's only enough room for a single thunk, which for real-life code isn't enough. The error case only happens when there are many branch statements very close to each other (0 or 1 instructions apart), with the function at the finalization barrier small. There's a FIXME on what to do if we hit this case, but that suggestion sounds complicated to me (see end of PR51578 comment 5 for why). Instead, just leave more room for thunks. Chromium's unit_tests links fine with room for 3 thunks. Leave room for 100, which should fix this for most cases in practice. There's little cost for leaving lots of room: This slop value only determines when we finalize sections, and we insert thunks for forward jumps into unfinalized sections. So leaving room means we'll need a few more thunks, but the thunk jump range is 128 MiB while a single thunk is just 12 bytes. For Chromium's unit_tests: With a slop of 3: thunk calls = 355418, thunks = 10903 With a slop of 100: thunk calls = 355426, thunks = 10904 Chances are 100 is enough for all use cases we'll hit in practice, but even bumping it to 1000 would probably be fine. Differential Revision: https://reviews.llvm.org/D108930 |
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| cmake/modules | ||
| docs | ||
| include/lld | ||
| lib | ||
| test | ||
| tools/lld | ||
| unittests | ||
| utils | ||
| wasm | ||
| .clang-format | ||
| .clang-tidy | ||
| .gitignore | ||
| CMakeLists.txt | ||
| CODE_OWNERS.TXT | ||
| LICENSE.TXT | ||
| README.md | ||
README.md
LLVM Linker (lld)
This directory and its subdirectories contain source code for the LLVM Linker, a modular cross platform linker which is built as part of the LLVM compiler infrastructure project.
lld is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt.
Benchmarking
In order to make sure various developers can evaluate patches over the same tests, we create a collection of self contained programs.
It is hosted at https://s3-us-west-2.amazonaws.com/linker-tests/lld-speed-test.tar.xz
The current sha256 is 10eec685463d5a8bbf08d77f4ca96282161d396c65bd97dc99dbde644a31610f.