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Re: Reload patch v4



  In message <35F83D6A.66E@tssc.co.nz>you write:
  > Wouldn't this help [compiler] performance a little as well?  I imagine
  > any improvements would depend on access paterns (ie, separate arrays
  > accessed with similar indexes or each array being scanned separatly).
Accesses into the reg structure at least tend to be sequential by reg
or nearly random.  From a locality of reference standpoint it isn't
likely to help much.

It does help simplify address calculations though, and on some ports
that can be important (particularly the PA where lots computations of
address in the static store tends to force %r1 to be spilled).

The global rtl structure may help locality some.  I haven't actually
tried any experiments. 


  > Either way, this sort of thing would definity improve readability, which
  > is much more important in a compiler than raw performance.
It improves readability and makes infrastructure changes easier.  For
example converting the register array to virtual arrays was basically
straightforward after we had all the register info in a single
structure.

jeff


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