diff options
Diffstat (limited to 'gmp/mpn/x86_64/rsh1sub_n.asm')
| -rw-r--r-- | gmp/mpn/x86_64/rsh1sub_n.asm | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/gmp/mpn/x86_64/rsh1sub_n.asm b/gmp/mpn/x86_64/rsh1sub_n.asm new file mode 100644 index 0000000000..b08bba4735 --- /dev/null +++ b/gmp/mpn/x86_64/rsh1sub_n.asm @@ -0,0 +1,146 @@ +dnl AMD64 mpn_rsh1sub_n -- rp[] = (up[] - vp[]) >> 1 + +dnl Copyright 2003, 2005 Free Software Foundation, Inc. + +dnl This file is part of the GNU MP Library. + +dnl The GNU MP Library is free software; you can redistribute it and/or modify +dnl it under the terms of the GNU Lesser General Public License as published +dnl by the Free Software Foundation; either version 3 of the License, or (at +dnl your option) any later version. + +dnl The GNU MP Library is distributed in the hope that it will be useful, but +dnl WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY +dnl or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public +dnl License for more details. + +dnl You should have received a copy of the GNU Lesser General Public License +dnl along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. + +include(`../config.m4') + + +C cycles/limb +C K8,K9: 2.14 (mpn_add_n + mpn_rshift need 4.125) +C K10: 2.14 (mpn_add_n + mpn_rshift need 4.125) +C P4: 12.75 +C P6-15: 3.75 + +C TODO +C * Rewrite to use indexed addressing, like addlsh1.asm and sublsh1.asm. +C * Try to approach the cache bandwidth 1.5 c/l. It should be possible. + +C INPUT PARAMETERS +define(`rp',`%rdi') +define(`up',`%rsi') +define(`vp',`%rdx') +define(`n',`%rcx') +define(`n32',`%ecx') + +ASM_START() + TEXT + ALIGN(16) + .byte 0,0,0,0,0,0,0,0 +PROLOGUE(mpn_rsh1sub_n) + pushq %rbx C 1 + + xorl %eax, %eax + movq (up), %rbx + subq (vp), %rbx + + rcrq %rbx C rotate, save acy + adcl %eax, %eax C return value + + movl n32, %r11d + andl $3, %r11d + + cmpl $1, %r11d + je L(do) C jump if n = 1 5 9 ... + +L(n1): cmpl $2, %r11d + jne L(n2) C jump unless n = 2 6 10 ... + addq %rbx, %rbx C rotate carry limb, restore acy + movq 8(up), %r10 + sbbq 8(vp), %r10 + leaq 8(up), up + leaq 8(vp), vp + leaq 8(rp), rp + rcrq %r10 + rcrq %rbx + movq %rbx, -8(rp) + jmp L(cj1) + +L(n2): cmpl $3, %r11d + jne L(n3) C jump unless n = 3 7 11 ... + addq %rbx, %rbx C rotate carry limb, restore acy + movq 8(up), %r9 + movq 16(up), %r10 + sbbq 8(vp), %r9 + sbbq 16(vp), %r10 + leaq 16(up), up + leaq 16(vp), vp + leaq 16(rp), rp + rcrq %r10 + rcrq %r9 + rcrq %rbx + movq %rbx, -16(rp) + jmp L(cj2) + +L(n3): decq n C come here for n = 4 8 12 ... + addq %rbx, %rbx C rotate carry limb, restore acy + movq 8(up), %r8 + movq 16(up), %r9 + sbbq 8(vp), %r8 + sbbq 16(vp), %r9 + movq 24(up), %r10 + sbbq 24(vp), %r10 + leaq 24(up), up + leaq 24(vp), vp + leaq 24(rp), rp + rcrq %r10 + rcrq %r9 + rcrq %r8 + rcrq %rbx + movq %rbx, -24(rp) + movq %r8, -16(rp) +L(cj2): movq %r9, -8(rp) +L(cj1): movq %r10, %rbx + +L(do): + shrq $2, n C 4 + je L(end) C 2 + ALIGN(16) +L(oop): addq %rbx, %rbx C rotate carry limb, restore acy + + movq 8(up), %r8 + movq 16(up), %r9 + sbbq 8(vp), %r8 + sbbq 16(vp), %r9 + movq 24(up), %r10 + movq 32(up), %r11 + sbbq 24(vp), %r10 + sbbq 32(vp), %r11 + + leaq 32(up), up + leaq 32(vp), vp + + rcrq %r11 C rotate, save acy + rcrq %r10 + rcrq %r9 + rcrq %r8 + + rcrq %rbx + movq %rbx, (rp) + movq %r8, 8(rp) + movq %r9, 16(rp) + movq %r10, 24(rp) + movq %r11, %rbx + + leaq 32(rp), rp + decq n + jne L(oop) + +L(end): movq %rbx, (rp) + popq %rbx + ret +EPILOGUE() |