i386 integer comparison patch

Jeffrey A Law law@cygnus.com
Sun May 31 20:47:00 GMT 1998


  In message < 199805310444.AAA18433@jwlab.FEITH.COM >you write:
  > Hello,
  > 
  > This change updates the integer comparison patterns so that
  > the register allocator can hopefully do a better job.
  > 
  > ChangeLog:
  > 
  > Sun May 31 00:28:08 EDT 1998  John Wehle  (john@feith.com)
  > 
  > 	* i386.md (cmpsi_1, cmphi_1, cmpqi_1): Update constraints
  > 	and remove code which set CC_REVERSED since reload should
  > 	ensure that the operands are already the correct type.
  > 	(movsicc+1, movsicc+2, movhicc+1, movhicc+2, movsfcc+1,
  > 	movsfcc+2, movdfcc+1, movdfcc+2, movxfcc+1, movxfcc+2,
  > 	movdicc+1, movdicc+2): Update the constraints and specify
  > 	the mode for the comparison operands.
Well, my experiments how this is generally a lose, though a rather
small one.   Have you done any experiments which show that register
allocation is improved with this patch?

jeff



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