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Re: Canonical type nodes, or, comptypes considered harmful
- From: Joern RENNECKE <joern dot rennecke at st dot com>
- To: Mike Stump <mrs at apple dot com>
- Cc: Dale Johannesen <dalej at apple dot com>, Gabriel Dos Reis <gdr at integrable-solutions dot net>, "Joseph S. Myers" <joseph at codesourcery dot com>, Doug Gregor <doug dot gregor at gmail dot com>, gcc at gcc dot gnu dot org
- Date: Fri, 10 Nov 2006 13:27:54 +0000
- Subject: Re: Canonical type nodes, or, comptypes considered harmful
- References: <45539862.1060307@st.com> <66848AD9-07A5-42B9-A004-F41AA0D24195@apple.com>
Mike Stump wrote:
Now, what are the benefits and weaknesses between mine and your, you
don't have to carry around type_context the way mine would, that's a
big win. You don't have to do anything special move a reference to a
type around, that's a big win. You have to do a structural walk if
there are any bits that are used for type equality.
No, these bits can be placed together - a structural walk is only
necessary when (some of) these bits themselves need more scrutiny - i.e.
on at least one of the
sides some of the constituent parts is partially incomplete. And I
can't see how you can avoid that complexity.
In my scheme, I don't have to. I just have a vector of items, they
are right next to each other, in the same cache line.
Again, the equality of the items might not not trivial.