bodies_by_type: SVt_PVFM bodies use an arena, just like all other bodies - #24808
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richardleach wants to merge 5 commits into
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richardleach wants to merge 5 commits into
richardleach wants to merge 5 commits into
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On a build that uses SV arenas, only the SVt_PVFM body is allocated, with all other types being bodiless (e.g. SVt_IV) or using arenas. Hot functions that add or remove bodies therefore have to perform a check - which is effectively for a rare type - every time and contain code to deal with both arenas & allocations. This commit makes this body type also use an arena, allowing for simplification of any core function that adds or removes a body.
This commit also duplicates the "free_rv" code for SVt_IV to directly use rather than jumping to the shared code to hopefully help codegen. (With gcc, at least, this commit led to better code layout for bodiless SVs, regardless of content. Overall this commit caused a slight reduction in the number of generated instructions, so the "free_rv" duplication wasn't at the cost of code bloat.)
tonycoz
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Sep 17, 2026
tonycoz
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My first thought: what's a PVFM? (yeah, formats)
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On a build that uses SV arenas, only the
SVt_PVFMbody is allocated,with all other types being bodiless (e.g.
SVt_IV) or using arenas.Hot functions that add or remove bodies therefore have to perform a
check - which is effectively for a rare type - every time and contain
code to deal with both arenas & allocations.
The first commit in this PR makes
SVt_PVFMbodies also use an arena.This enables simplification of any core function that adds or removes a body.
The subsequent PRs make such changes to:
Perl_newSV_typePerl_sv_upgradeS_sv_dup_commonPerl_sv_clear