sv_upgrade: minor AV/HV new_body refactoring #19270
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xav_alloc is a member of the xpvav struct. The instance modified here would have been Zero()ed several lines previously, so both sides of this if() branch should be no-ops. With gcc 8.3.0 the compiled function is about 6 instructions smaller.
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The one concern I have is whether or not it's really portable & safe to initialize the |
It does seem a bit strange to mix designated and non-designated initialization, but it is well defined in C99 and C11. Designating xmg_u might be clearer though: and works for me. |
For both the AV and HV cases, the new body is Zero()ed but then various struct members are set to non-zero values. Now that we support parts of c99, it seems more efficient to use compound literals to initailize the struct members. With gcc v8.3.0, the compiled function is smaller by 25 instructions. sv.o is slightly smaller, but the final perl binary size is unchanged.
richardleach
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Thanks, I've done that, rebased and pushed. |
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