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Remove usage of --use-old-text for BOLT #114649

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Aug 9, 2023
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Remove usage of --use-old-text for BOLT #114649

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7 changes: 6 additions & 1 deletion src/tools/opt-dist/src/bolt.rs
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Expand Up @@ -65,8 +65,13 @@ pub fn bolt_optimize(path: &Utf8Path, profile: &LlvmBoltProfile) -> anyhow::Resu
.arg("-jump-tables=move")
// Fold functions with identical code
.arg("-icf=1")
// The following flag saves about 50 MiB of libLLVM.so size.
// However, it succeeds very non-deterministically. To avoid frequent artifact size swings,
// it is kept disabled for now.
// FIXME(kobzol): try to re-enable this once BOLT in-place rewriting is merged or after
// we bump LLVM.
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@Kobzol has this been reevaluated yet?

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Yes, I tried it a few weeks ago:
image-6.png

Sadly, it's still quite unstable. Asked the BOLT people about it, but we haven't got anywhere yet.

// Try to reuse old text segments to reduce binary size
.arg("--use-old-text")
// .arg("--use-old-text")
// Update DWARF debug info in the final binary
.arg("-update-debug-sections")
// Print optimization statistics
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