Allocator claims rework - #727
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davidchisnall
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Do you know why this got bigger?
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My unverified suspicion is that it's the ChainPredecessor tagged union (a pointer and a flag) vs just the uint16_t we were carrying around before?
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Rather than an absolue address, this takes an offset relative to the heap start address.
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All this so we can avoid the need to take references to bitfield members.
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This changes the internal workings of
Claimobjects within the heap allocator, specifically so we no longer need to take a pointer to the claims chain head field within aMChunkHeader. With that change made, we should be able to vary the widths of owner and claims (encoded) pointer fields withinMChunkHeaderandClaims, and in particular make this width larger than 16 bits, which is one, and possibly the simplest, approach to getting us to supporting more than 512KiB heaps.