| dnl PowerPC-64/mode32 mpn_sub_n -- Subtract two limb vectors of the same |
| dnl length and store difference in a third limb vector. |
| |
| dnl Copyright 1999, 2000, 2001, 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 POWER3/PPC630: ? |
| C POWER4/PPC970: 4.25 |
| |
| C INPUT PARAMETERS |
| C rp r3 |
| C up r4 |
| C vp r5 |
| C n r6 |
| |
| ASM_START() |
| PROLOGUE(mpn_sub_n) |
| mtctr r6 C copy size into CTR |
| addic r0, r6, -1 C set cy |
| ld r8, 0(r4) C load least significant s1 limb |
| ld r0, 0(r5) C load least significant s2 limb |
| addi r3, r3, -8 C offset res_ptr, it's updated before it's used |
| bdz L(end) C If done, skip loop |
| |
| L(oop): ld r9, 8(r4) C load s1 limb |
| ld r10, 8(r5) C load s2 limb |
| subfe r7, r0, r8 C subtract limbs with cy, set cy |
| srdi r6, r0, 32 |
| srdi r11, r8, 32 |
| subfe r6, r6, r11 |
| std r7, 8(r3) C store result limb |
| bdz L(exit) C decrement CTR and exit if done |
| ldu r8, 16(r4) C load s1 limb and update s1_ptr |
| ldu r0, 16(r5) C load s2 limb and update s2_ptr |
| subfe r7, r10, r9 C subtract limbs with cy, set cy |
| srdi r6, r10, 32 |
| srdi r11, r9, 32 |
| subfe r6, r6, r11 |
| stdu r7, 16(r3) C store result limb and update res_ptr |
| bdnz L(oop) C decrement CTR and loop back |
| |
| L(end): subfe r7, r0, r8 |
| srdi r6, r0, 32 |
| srdi r11, r8, 32 |
| subfe r6, r6, r11 |
| std r7, 8(r3) C store ultimate result limb |
| subfe r3, r0, r0 C load !cy into ... |
| subfic r4, r3, 0 C ... return value register |
| li r3, 0 C zero extend return value |
| blr |
| L(exit): subfe r7, r10, r9 |
| srdi r6, r10, 32 |
| srdi r11, r9, 32 |
| subfe r6, r6, r11 |
| std r7, 16(r3) |
| subfe r3, r0, r0 C load !cy into ... |
| subfic r4, r3, 0 C ... return value register |
| li r3, 0 C zero extend return value |
| blr |
| EPILOGUE() |
