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Re: subreg_regno_offset

   From: Joern Rennecke <>
   Date: Tue, 21 May 2002 21:21:06 +0100

   I think it is better to have a simple default definition for
   subreg_regno_offset - e.g., just return what is currently calculated
   as ymode (of course you can use a run-time generated lookup table to
   speed that up).  Any target that does not fit into that scheme can
   then define its own version.
   With the lookup table, the vanilla version can even be made to fit
   targets where single precision values are held in double-precision
   registers, by looping for each mode through MODE_WIDER_MODE and using
   the size of the largest mode that occupies the same number of hard

I don't know, I'd really like to keep this code generic and just
made the generic code more intelligent and faster.

For example, note that when we are creating SUBREG expressions it
would be easy to compute the register offset and store it in the
just as cheap as SUBREG_REG.

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