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-10.01.-28163 22:59, Tony Finch wrote:
On Fri, 25 Feb 2011, Peter Cawley wrote:
2011/2/24 Yura Sokolov<>:
So that there is 3bits for tagging.

Currently Lua uses 13 different tag values, so that it would be tricky to
pack them into three bits :)
If you're willing to pay the price of an extra indirection, you might
be able to get away with using a single tag value for all GC types, as
the GC header stores the tag value.
Or steal another three bits from the bottom of the pointer...

I thought about both.
Both approaches means extra branching on extracting tag and saving it, I think.

Another possible solution could be utilization of fact that higher addresses reserved for operating system's core.
So that, userland addresses are all falling in a 47 bit values.

Can anybody confirm or refute this sentence?

Sokolov Yura aka funny_falcon.