Build the wasm module with -DNDEBUG - #3066
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`rake wasm:build` compiled the parser without `NDEBUG`, so every `RBS_ASSERT`
survived into `rbs_parser.wasm`. The MRI extension already drops them
(ext/rbs_extension/extconf.rb), and the assertions that matter sit on the
hottest paths there are: two per character in `rbs_encoding.c`, one per
character in `rbs_skip`, and five around the constant pool. Each one is an
out-of-line varargs call to `rbs_assert_impl`, which the compiler cannot inline
away, so the cost is paid on every character lexed.
Parsing core/ + stdlib/ (250 files, 4.3MB) through a WASI host, best of 10:
assert build 75.7 ms
NDEBUG build 61.9 ms (-18%)
Measured the same on wasmtime and on V8. The serialized ASTs for all 250 files
are byte-identical between the two builds.
`DEBUG=1 rake wasm:build` keeps the assertions, matching the DEBUG convention
extconf.rb and the prepare_bench / prepare_profiling tasks already use.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012uu4EqN6azBeVjM9F71TUp
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rake wasm:buildwas compiling the parser withoutNDEBUG, so everyRBS_ASSERTsurvived intorbs_parser.wasm— unlike the MRI extension, which already drops them inext/rbs_extension/extconf.rb.It was up to 20% slower with
RBS_ASSERTcalls.This adds
-DNDEBUGto the wasm build, withDEBUG=1 rake wasm:buildas the escape hatch for keeping the assertions, matching theDEBUGconventionextconf.rband theprepare_bench/prepare_profilingtasks already use.Measurements
Parsing
core/+stdlib/(250 files, 4.3MB), best of 10, three rounds:-DNDEBUG