gcc-2.7 creates faster code than pgcc-1.1.1

Jeffrey A Law law@hurl.cygnus.com
Thu Mar 4 18:08:00 GMT 1999


  In message < 199903050001.BAA00973@mira.isdn.cs.tu-berlin.de >you write:
  > > -  if ((TARGET_ZERO_EXTEND_WITH_AND || REGNO (operands[0]) == 0)
  > > +  if ((TARGET_ZERO_EXTEND_WITH_AND || (0 & REGNO (operands[0]) == 0))
  > 
  > It's late, so I'm probably going to say stupid things, but ...
  > 
  > Isn't (0 & REGNO (operands[0]) == 0) always 0? Why isn't the condition
  > just deleted?
Disabling the code like that is actually the wrong thing to do for certain
processor variants.

I need to dust off my changes to this code which do the right thing when
optimizing for size, PPro, Pent and older x86 variants.

It's not as simple as just deleting the test like that.

jeff


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