Create and link against libllvmlibc-sparse#40
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Using musl solved our static linking woes, but introduced performance regressions. Specifically, calls to memset, memcpy, memcmp, and strlen became more noticeable in profiles. Build llvmlibc, extract the .o files from the .a for those 4, repack them in a new .a, then link against that. llvmlibc's strlen isn't measurably better, but the author is aware and interested in fixing. Fixes #39
compnerd
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This feels like tihi worthy.
| -C llvm-project/stage3.cmake \ | ||
| -D LLVM_DEFAULT_TARGET_TRIPLE=$(clang -print-target-triple) \ | ||
| -S llvm-project/llvm \ | ||
| -D CMAKE_EXE_LINKER_FLAGS="-static -lc++abi -ljemalloc -lllvmlibc-sparse -Wl,--allow-multiple-definition" \ |
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I tend to prefer -Xlinker --allow-multiple-definition. However, this is gross either way.
nathanchance
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LGTM with some minor nits.
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Using musl solved our static linking woes, but introduced performance
regressions. Specifically, calls to memset, memcpy, memcmp, and strlen
became more noticeable in profiles.
Build llvmlibc, extract the .o files from the .a for those 4, repack
them in a new .a, then link against that.
llvmlibc's strlen isn't measurably better, but the author is aware and
interested in fixing.
See
#39 (comment)
for performance measurements.
Fixes #39