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Remove forced inlining from Span<T>.ToArray - #132635
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Could you please also apply ImmutableArray simplifications that were noticed during investigation of this issue #119713 (comment) ? |
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Fixes #119713.
Summary
Span<T>.ToArray()is currently marked withAggressiveInlining, whileReadOnlySpan<T>.ToArray()is not.This change removes the forced-inlining hint from
Span<T>.ToArray()andallows the JIT to make its normal profitability decision.
Rationale
Existing JIT-diff experiments discussed in #119713 evaluated both ways of
making the two implementations consistent.
Adding
AggressiveInliningtoReadOnlySpan<T>.ToArray()resulted insubstantially more code-size churn, including multiple regressions.
By comparison, removing
AggressiveInliningfromSpan<T>.ToArray()had amuch smaller code-size impact.
Given that
ToArray()allocates and does not necessarily benefit from beingforcibly inlined at every call site, removing the hint is the more conservative
way to make the implementations consistent.
The runtime behavior of
ToArray()is unchanged.Validation
The code change is limited to removing the
AggressiveInliningattribute.The JIT-diff experiments referenced in the issue discussion are:
Credit to @xtqqczze for running the JIT-diff experiments used to evaluate the
tradeoff.