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Integrate WASM-based Prism parser into standard build#9184

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headius wants to merge 7 commits intojruby:masterfrom
headius:wasm_prism
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Integrate WASM-based Prism parser into standard build#9184
headius wants to merge 7 commits intojruby:masterfrom
headius:wasm_prism

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@headius headius commented Jan 22, 2026 •
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This continues the integration of Prism parser wrapper libraries from the jruby-prism project by shading it in and including the new WASM support and Chicory libraries.

This is a prototype of how it should eventually look and this PR is intended to iterate.

Notable behavior changes so far:

  • If the prism parser is enabled with -Xparser.prism but the dynamic library is not configured or present, it will fall back on the wasm parser.
  • If the prism parser is enabled with -Xparser.prism.wasm the wasm parser will be used.
  • The parser statistics output now prints the actual parser class in use.
  • All dependencies are shaded in and moved to internal packages as appropriate.

The artifacts this depends on comes from:

@headius headius added this to the JRuby 10.1.0.0 milestone Jan 22, 2026
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headius commented Jan 22, 2026

Performance of a "gem list" benchmark with legacy parser versus wasm prism (after sufficient warmup):

legacy:

Parser Statistics:
  Generic:
    parser type: class org.jruby.parser.Parser
    bytes processed: 1451897
    files parsed: 155
    evals parsed: 145
    time spent parsing(s): 0.028649121
    time spend parsing + building: 0.040757128000000004
  IRBuild:
    build time: 0.012108007

wasm prism:

Parser Statistics:
  Generic:
    parser type: class org.jruby.prism.parser.ParserPrismWasm
    bytes processed: 1849537
    files parsed: 155
    evals parsed: 145
    time spent parsing(s): 0.383976125
    time spend parsing + building: 0.39173020000000003
  Prism:
    time C parse+serialize: 0.0
    time deserializing: 0.009623121
    serialized bytes: 1224017
    serialized to source ratio: x0.66179645
  IRBuild:
    build time: 0.007754075

Wierdly this runs much better with tiered compilation turned off (-J-XX:-TieredCompilation):

Parser Statistics:
  Generic:
    parser type: class org.jruby.prism.parser.ParserPrismWasm
    bytes processed: 1849537
    files parsed: 155
    evals parsed: 145
    time spent parsing(s): 0.07803804
    time spend parsing + building: 0.085966137
  Prism:
    time C parse+serialize: 0.0
    time deserializing: 0.008756323
    serialized bytes: 1224017
    serialized to source ratio: x0.66179645
  IRBuild:
    build time: 0.007928097

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headius commented Jan 22, 2026

Benchmark command line:

jruby -J-XX:-TieredCompilation -Xparser.summary -Xparser.prism -e 'loop { t = Time.now; ruby = org.jruby.Ruby.newInstance; ruby.loadService.require("rubygems"); ruby.loadService.require("rubygems/gem_runner"); ruby.evalScriptlet("Gem::GemRunner.new.run [%{list}]"); ruby.tearDown; $stderr.puts Time.now - t }'

Remove -Xprism.parser or the tiered compilation flag to test without them.

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@headius headius mentioned this pull request Jan 27, 2026
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@headius
Integrate jruby-prism 2.0
a8ed70c 
This integrates jruby-prism 2.0 by shading it into our main JRuby
jar and loading it from there. Incoming packages considered to be
for internal use are moved under `org.jruby.internal`. The output
of parser statistics now shows the actual class of the parser,
since either or both can be activated now.
@headius
Don't assume this is a RootNode
f452b44 
If this is parsed by Prism, it's a ProgramNode contained in a
ParseResult, so just use the ParseResult.
@headius
Update for recent naming changes
6d2db2f
@headius headius changed the base branch from 10.1-dev to master February 24, 2026 22:18
@headius headius mentioned this pull request Mar 9, 2026
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@headius @CufeHaco @enebo