Joachim Breitner <m...@joachim-breitner.de> writes: > Hi, > > Am Sonntag, den 11.06.2017, 10:44 -0400 schrieb Ben Gamari: >> This is certainly one consideration. Another is that you would also >> need to teach the garbage collector to understand closures with sub- >> word-size fields. Currently we can encode whether each field of a >> closure is a pointer or not with a simple bitmap. If we naively >> allowed smaller fields we would need to increase the granularity of >> this representation to encode bytes. >> >> Of course, one way to work around this would be to impose an >> invariant that guarantees that pointers are always word-aligned. Then >> we would probably want to shuffle sub-word sized fields, allowing two >> Word16s to inhabit a single word. > > that is not an issue; we already sort field into pointers first, and > non-pointers later. So all pointers are at the beginning and nicely > aligned, and all the non-pointer data can follow in whatever weird > format. The GC only needs to know how many words in total are used by > the non-pointer data. > Ahh, great point. I stand corrected.
Cheers, - Ben
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