On Mon, Jul 29, 2013 at 5:23 PM, Bert Freudenberg bert@freudenbergs.de wrote:
On 2013-07-29, at 23:59, Igor Stasenko siguctua@gmail.com wrote:
just a thought.. imo using identity hash field for instances of Float while probable, but in fact really impractical.
in that sense, what you think about removing filling the identity hash field and leave it always == 0.. saving some instructions to make float allocation a bit faster?
i am talking about genAllocFloatValue: dpreg into: resultReg scratchReg: scratch1 scratchReg: scratch2
IMHO, turning Floats into the only objects in the system that cause severe collisions in IdentitySets / Dictionaries should not be done lightly. It's a step away from "every object is equal" which I think is an important principle.
+1. I recently was investigating memory consumption in a large application image and discovered > 100MB in Float instances..!! But guess what, many many of them were the same number (0.0, 1.0, 100.0, -100.0, and several others had many occurrences) -- prompting me to wonder whether I should try to canonicalize them upon materialization, via an IdentityDictionary..
I haven't tried it yet but.. if their identityHash'es were all 0 then it'd be pointless to try.
So I like your other idea about using the float itself as the identityHash, however that would be done, at least they'd be unique and consistent.