| dnl PowerPC-32 mpn_submul_1 -- Multiply a limb vector with a limb and subtract |
| dnl the result from a second limb vector. |
| |
| dnl Copyright 1995, 1997, 1998, 2000, 2002, 2005 Free Software Foundation, |
| dnl 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 603e: ? |
| C 604e: 7.5 |
| C 75x (G3): 9.3-15 |
| C 7400,7410 (G4): 9.3-15 |
| C 744x,745x (G4+): 10.5 |
| C power4/ppc970: 6.75 |
| C power5: 6.5 |
| |
| C INPUT PARAMETERS |
| C rp r3 |
| C up r4 |
| C n r5 |
| C vl r6 |
| |
| C This is optimized for the PPC604. See addmul_1.asm for additional comments. |
| |
| ASM_START() |
| PROLOGUE(mpn_submul_1) |
| cmpwi cr0,r5,9 C more than 9 limbs? |
| bgt cr0,L(big) C branch if more than 9 limbs |
| |
| mtctr r5 |
| lwz r0,0(r4) |
| mullw r7,r0,r6 |
| mulhwu r10,r0,r6 |
| lwz r9,0(r3) |
| subfc r8,r7,r9 |
| addc r7,r7,r8 C invert cy (r7 is junk) |
| addi r3,r3,-4 |
| bdz L(end) |
| L(loop): |
| lwzu r0,4(r4) |
| stwu r8,4(r3) |
| mullw r8,r0,r6 |
| adde r7,r8,r10 |
| mulhwu r10,r0,r6 |
| lwz r9,4(r3) |
| addze r10,r10 |
| subfc r8,r7,r9 |
| addc r7,r7,r8 C invert cy (r7 is junk) |
| bdnz L(loop) |
| L(end): stw r8,4(r3) |
| addze r3,r10 |
| blr |
| |
| L(big): stmw r30,-32(r1) |
| addi r5,r5,-1 |
| srwi r0,r5,2 |
| mtctr r0 |
| |
| lwz r7,0(r4) |
| mullw r8,r7,r6 |
| mulhwu r0,r7,r6 |
| lwz r7,0(r3) |
| subfc r7,r8,r7 |
| addc r8,r8,r7 |
| stw r7,0(r3) |
| |
| L(loopU): |
| lwz r7,4(r4) |
| lwz r12,8(r4) |
| lwz r30,12(r4) |
| lwzu r31,16(r4) |
| mullw r8,r7,r6 |
| mullw r9,r12,r6 |
| mullw r10,r30,r6 |
| mullw r11,r31,r6 |
| adde r8,r8,r0 C add cy_limb |
| mulhwu r0,r7,r6 |
| lwz r7,4(r3) |
| adde r9,r9,r0 |
| mulhwu r0,r12,r6 |
| lwz r12,8(r3) |
| adde r10,r10,r0 |
| mulhwu r0,r30,r6 |
| lwz r30,12(r3) |
| adde r11,r11,r0 |
| mulhwu r0,r31,r6 |
| lwz r31,16(r3) |
| addze r0,r0 C new cy_limb |
| subfc r7,r8,r7 |
| stw r7,4(r3) |
| subfe r12,r9,r12 |
| stw r12,8(r3) |
| subfe r30,r10,r30 |
| stw r30,12(r3) |
| subfe r31,r11,r31 |
| stwu r31,16(r3) |
| subfe r11,r11,r11 C invert ... |
| addic r11,r11,1 C ... carry |
| bdnz L(loopU) |
| |
| andi. r31,r5,3 |
| mtctr r31 |
| beq cr0,L(endx) |
| |
| L(loopE): |
| lwzu r7,4(r4) |
| mullw r8,r7,r6 |
| adde r8,r8,r0 C add cy_limb |
| mulhwu r0,r7,r6 |
| lwz r7,4(r3) |
| addze r0,r0 C new cy_limb |
| subfc r7,r8,r7 |
| addc r8,r8,r7 |
| stwu r7,4(r3) |
| bdnz L(loopE) |
| L(endx): |
| addze r3,r0 |
| lmw r30,-32(r1) |
| blr |
| EPILOGUE(mpn_submul_1) |
