| dnl Pentium-4 mpn_copyi -- copy limb vector, incrementing. |
| |
| dnl Copyright 1999-2001 Free Software Foundation, Inc. |
| |
| dnl This file is part of the GNU MP Library. |
| dnl |
| dnl The GNU MP Library is free software; you can redistribute it and/or modify |
| dnl it under the terms of either: |
| dnl |
| dnl * the GNU Lesser General Public License as published by the Free |
| dnl Software Foundation; either version 3 of the License, or (at your |
| dnl option) any later version. |
| dnl |
| dnl or |
| dnl |
| dnl * the GNU General Public License as published by the Free Software |
| dnl Foundation; either version 2 of the License, or (at your option) any |
| dnl later version. |
| dnl |
| dnl or both in parallel, as here. |
| dnl |
| 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 General Public License |
| dnl for more details. |
| dnl |
| dnl You should have received copies of the GNU General Public License and the |
| dnl GNU Lesser General Public License along with the GNU MP Library. If not, |
| dnl see https://www.gnu.org/licenses/. |
| |
| |
| dnl The rep/movsl is very slow for small blocks on pentium4. Its startup |
| dnl time seems to be about 110 cycles. It then copies at a rate of one |
| dnl limb per cycle. We therefore fall back to an open-coded 2 c/l copying |
| dnl loop for smaller sizes. |
| |
| dnl Ultimately, we may want to use 64-bit movd or 128-bit movdqu in some |
| dnl nifty unrolled arrangement. Clearly, that could reach much higher |
| dnl speeds, at least for large blocks. |
| |
| include(`../config.m4') |
| |
| |
| defframe(PARAM_SIZE, 12) |
| defframe(PARAM_SRC, 8) |
| defframe(PARAM_DST, 4) |
| |
| TEXT |
| ALIGN(8) |
| |
| PROLOGUE(mpn_copyi) |
| deflit(`FRAME',0) |
| |
| movl PARAM_SIZE, %ecx |
| cmpl $150, %ecx |
| jg L(replmovs) |
| |
| movl PARAM_SRC, %eax |
| movl PARAM_DST, %edx |
| movl %ebx, PARAM_SIZE |
| testl %ecx, %ecx |
| jz L(end) |
| |
| L(loop): |
| movl (%eax), %ebx |
| leal 4(%eax), %eax |
| addl $-1, %ecx |
| movl %ebx, (%edx) |
| leal 4(%edx), %edx |
| |
| jnz L(loop) |
| |
| L(end): |
| movl PARAM_SIZE, %ebx |
| ret |
| |
| L(replmovs): |
| cld C better safe than sorry, see mpn/x86/README |
| |
| movl %esi, %eax |
| movl PARAM_SRC, %esi |
| movl %edi, %edx |
| movl PARAM_DST, %edi |
| |
| rep |
| movsl |
| |
| movl %eax, %esi |
| movl %edx, %edi |
| |
| ret |
| |
| EPILOGUE() |
