perl: wasm-opt -O2 post-link pass to reclaim ~470 KB (kd-lfas)#833
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build-perl.sh links with a load-bearing --no-gc-sections and applied no post-link size pass, leaving dead code from the 30 curated static XS extensions. Add a wasm-opt -O2 pass after the interpreter is re-collected and BEFORE install_local_binary applies fork instrumentation. Fork instrumentation hardcodes mutable-global offsets and must run last, so wasm-opt precedes it -- matching bash/git/php/vim. Plain -O2 (not -all) honors the binary's declared target_features; -all introduced exnref locals that break wasm-fork-instrument. Shipped perl.wasm 7,291,919 -> 6,822,373 bytes (-469,546 / -6.44%). ~3.06 MB of the binary is fork-instrumentation overhead, so this reclaims most of the non-instrumentation dead code. Verified on the instrumented recipe output: runtime-smoke 9/9, extended functional battery 21/21, fork/system/pipe smoke pass. -O2 over -Oz (only 0.45% smaller) for interpreter throughput + parity. Bump build.toml revision 2 -> 3 (output bytes change). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
…pass SUMMARY.md (measurement table, structural finding, decision), pass/fail/skip outcome lists, and the ext-smoke.ts / fork-smoke.ts harnesses used to verify the optimized binary. Evidence only; the .wasm artifacts are intentionally not committed. fork-smoke.ts is the first fork/system coverage for perl (candidate to promote via kd-gk6o CI wiring). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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What
Add a
wasm-opt -O2post-link, pre-fork-instrumentation pass topackages/registry/perl/build-perl.sh; bumpbuild.tomlrevision 2 → 3.build-perl.shlinks with a load-bearing--no-gc-sections(so wasm-ld's--allow-undefineddoesn't strip live Perl code) and applied no post-link sizepass, leaving dead code from the 30 curated static XS extensions.
wasm-opt -O2reclaims it. It runs before
install_local_binary's fork instrumentation,which hardcodes mutable-global offsets and must run last — matching
bash/git/php/vim. Plain
-O2(not-all) honors the binary's declaredtarget_features;-allintroducedexnreflocals that breakwasm-fork-instrument.Size
Shipped
perl.wasm7,291,919 → 6,822,373 bytes (−469,546 / −6.44%).Note: ~3.06 MB of the shipped binary is fork-instrumentation overhead (perl
imports
kernel_fork+kernel_execve), not dead code — so wasm-opt reclaims mostof the remaining non-instrumentation slack.
-Ozwas measured only 0.45%smaller;
-O2chosen for interpreter throughput + convention parity.Verification (on the instrumented recipe output, 6,822,373 B, 5 WPK exports)
unicode/
/u, sort, hashes, pack/unpack, POSIX math, List::Util, refs/closures)open('-|',LIST). Confirms fork instrumentation survives the pass (runtime/ext
smokes never fork).
The perl source compile is unchanged; validated
instrument(raw)==shippedbyte-identical, and exercised the added
wasm-opt -O2+ realinstall_local_binaryglue end-to-end. Full evidence in
test-runs/kd-lfas/SUMMARY.md.Stacking
Stacked on #821 (kd-k7zy, build-perl.sh rev 2). Base is the kd-k7zy branch;
retarget to
mainonce #821 merges. The pass could alternatively be folded into#821 if the maintainer prefers a single perl recipe PR.
Bead: kd-lfas.
🤖 Generated with Claude Code