2008-04-17 17:03:07 -04:00
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dnl Intel P6 mpn_add_n, mpn_sub_n -- mpn add or subtract.
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dnl Copyright 2003 Free Software Foundation, Inc.
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dnl
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dnl This file is part of the GNU MP Library.
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dnl
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dnl The GNU MP Library is free software; you can redistribute it and/or
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dnl modify it under the terms of the GNU Lesser General Public License as
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dnl published by the Free Software Foundation; either version 2.1 of the
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dnl License, or (at your option) any later version.
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dnl
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dnl The GNU MP Library is distributed in the hope that it will be useful,
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dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
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dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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dnl Lesser General Public License for more details.
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dnl
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dnl You should have received a copy of the GNU Lesser General Public
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dnl License along with the GNU MP Library; see the file COPYING.LIB. If
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dnl not, write to the Free Software Foundation, Inc., 51 Franklin Street,
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dnl Fifth Floor, Boston, MA 02110-1301, USA.
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include(`../config.m4')
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C P6: 2.7 cycles/limb
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C The K7 code runs quite well on P6, but this seems mainly due to the larger
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C amount of unrolling than in mpn/x86/aors_n.asm.
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C
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C P6 apparently doesn't separately rename the carry flag, or something, so a
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C loop holding a carry across decl or incl takes 4 cycles for the loop
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C control. Perhaps it's more when relying on out-of-order execution to hide
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C load latencies too.
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C
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C Not sure what the best approach would be. sbbl then addl to save and
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C restore the carry across the loop control would be a possibility. A
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C couple of experiments didn't get much joy, but such an approach would at
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C least avoid serialization, presumably.
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C
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2010-12-30 02:20:29 -05:00
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include_mpn(`x86/k7/add_n.asm')
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