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Re: why don't have 'umul' rtx code


Eric Fisher wrote:
hi

I'm not clear why we have 'udiv', but don't have 'umul' for Standard
Pattern Names. Does I need to define a nameless pattern for it?

Because non-widening multiplication is the same for signed and unsigned. We have:


  mul<mode1>3
  mul<mode1><mode2>3       (signed x signed)
  umul<mode1><mode2>3      (unsigned x unsigned)
  usmul<mode1><mode2>3     (unsigned x signed)
  umul<mode1>3_highpart    (unsigned x unsigned)
  smul<mode1>3_highpart    (signed x signed)

Paolo


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