83a425d25a compressor: use a prevector in compressed script serialization (William Casarin)
Pull request description:
This function was doing millions of unnecessary heap allocations during IBD.
I'm start to catalog unnecessary heap allocations as a pet project of mine: as-zero-as-possible-alloc IBD. This is one small step.
before:
after:
~should I type alias this?~ *I type aliased it*
This is a part of the Zero Allocations Project #18849 (ZAP1). This code came up as a place where many allocations occur.
ACKs for top commit:
Empact:
ACK 83a425d25a
elichai:
tACK 83a425d25a
sipa:
utACK 83a425d25a
Tree-SHA512: f0ffa6ab0ea1632715b0b76362753f9f6935f05cdcc80d85566774401155a3c57ad45a687942a1806d3503858f0bb698da9243746c8e2edb8fdf13611235b0e0
4cfe6c37d9
