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* Swapped lines in i386.c:k6_cost?
@ 2002-10-14  4:39 Zack Weinberg
  0 siblings, 0 replies; only message in thread
From: Zack Weinberg @ 2002-10-14  4:39 UTC (permalink / raw)
  To: gcc; +Cc: Jan Hubicka

The k6_cost structure initializer in i386.c on the mainline contains
this fragment:

  2,					/* cost of FDIV instruction.  */
  56,					/* cost of FABS instruction.  */
  2,					/* cost of FCHS instruction.  */
  56,					/* cost of FSQRT instruction.  */

I find it difficult to believe that the K6 only took two cycles to do
a floating-point divide, but absolute value operations took fifty-six.
Perhaps the costs for FDIV and FABS have been swapped?

zw

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2002-10-14  4:39 Swapped lines in i386.c:k6_cost? Zack Weinberg

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