Reduce deopt from print use of $_#8249
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headius merged 4 commits intojruby:9.5-devfrom May 29, 2024
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This tests the overhead of a method that calls print, given the optimization in jruby#8249.
We can reduce this deoptimization to when print is called with no arguments. Other forms do not need access to $_.
This tests the overhead of a method that calls print, given the optimization in jruby#8249.
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This started out as a call site optimization to pass
$_directly yoKernel#printorIO#printrather than provide it through a heap frame, but the simpler change is to reduce the deoptimization to only zero-arity. There are unlikely to be many non-core case for callingprintwithout any arguments other than for the core version.If there is such a case in the wild, we can revisit the call site optimization.
The patch as written here eliminates the frame requirement for all non-zero arity calls to
print.