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Re: FOUND! PA2.0 float performance problem




  In message <7av3il$8j2$1@palladium.transmeta.com>you write:
  > One thing to worry about is when running mixed mode single- and
  > double-precision things, where this allocation order may result in lots
  > of extra register pressure due to "fragmentation" of the FP register
  > file.  I don't know if that's an issue for gcc, but I can certainly see
  > it potentially resulting in nasty problems that are really hard to see. 
This kind of thing is an issue for small register class machines.  The PA
has 28 double precision registers and the existing algorithms to deal with
register file fragmentation should be able to cope.  Particularly since no
instruction uses more than 5 FP registers.  


jeff