[PATCH] T3/T4 sparc shifts, plus more timings
    Torbjorn Granlund 
    tg at gmplib.org
       
    Mon Apr  1 19:34:11 CEST 2013
    
    
  
David Miller <davem at davemloft.net> writes:
  Yes, understood.  We have to transpose a few of the shifts with
  their neighbouring arithmetic ops in this loop to make it optimal
  for Ultra-I/II/IIi
  
I found a powered up US2 and run time timing tests.  No slowdown there
for the new generic functions.
I suppose mpn/sparc64/ultrasparc1234/[lr]shift.asm are now redundant.
Clearly, the new lshiftc code is not optimal for US1 through US4.  It
runs 0.5 c/l slower on them all, compared to what one would hope for
2-way unrolled code.
-- 
Torbjörn
    
    
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