| Austin Schuh | dace2a6 | 2020-08-18 10:56:48 -0700 | [diff] [blame] | 1 | dnl HP-PA 2.0 64-bit mpn_udiv_qrnnd_r. |
| 2 | |
| 3 | dnl Copyright 2001-2003 Free Software Foundation, Inc. |
| 4 | |
| 5 | dnl This file is part of the GNU MP Library. |
| 6 | dnl |
| 7 | dnl The GNU MP Library is free software; you can redistribute it and/or modify |
| 8 | dnl it under the terms of either: |
| 9 | dnl |
| 10 | dnl * the GNU Lesser General Public License as published by the Free |
| 11 | dnl Software Foundation; either version 3 of the License, or (at your |
| 12 | dnl option) any later version. |
| 13 | dnl |
| 14 | dnl or |
| 15 | dnl |
| 16 | dnl * the GNU General Public License as published by the Free Software |
| 17 | dnl Foundation; either version 2 of the License, or (at your option) any |
| 18 | dnl later version. |
| 19 | dnl |
| 20 | dnl or both in parallel, as here. |
| 21 | dnl |
| 22 | dnl The GNU MP Library is distributed in the hope that it will be useful, but |
| 23 | dnl WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| 24 | dnl or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 25 | dnl for more details. |
| 26 | dnl |
| 27 | dnl You should have received copies of the GNU General Public License and the |
| 28 | dnl GNU Lesser General Public License along with the GNU MP Library. If not, |
| 29 | dnl see https://www.gnu.org/licenses/. |
| 30 | |
| 31 | include(`../config.m4') |
| 32 | |
| 33 | C This runs at about 280 cycles on both PA8000 and PA8500, corresponding to a |
| 34 | C bit more than 4 cycles/bit. |
| 35 | |
| 36 | C INPUT PARAMETERS |
| 37 | define(`n1',`%r26') |
| 38 | define(`n0',`%r25') |
| 39 | define(`d',`%r24') |
| 40 | define(`remptr',`%r23') |
| 41 | |
| 42 | define(`q',`%r28') |
| 43 | define(`dn',`%r29') |
| 44 | |
| 45 | define(`old_divstep', |
| 46 | `add,dc n0,n0,n0 |
| 47 | add,dc n1,n1,n1 |
| 48 | sub,*<< n1,d,%r22 |
| 49 | copy %r22,n1') |
| 50 | |
| 51 | define(`divstep', |
| 52 | `add n0,n0,n0 |
| 53 | add,dc n1,n1,n1 |
| 54 | sub n1,d,%r1 |
| 55 | add,dc q,q,q |
| 56 | cmpclr,*<< n1,d,%r0 |
| 57 | copy %r1,n1 |
| 58 | ') |
| 59 | |
| 60 | ifdef(`HAVE_ABI_2_0w', |
| 61 | ` .level 2.0w |
| 62 | ',` .level 2.0 |
| 63 | ') |
| 64 | PROLOGUE(mpn_udiv_qrnnd_r) |
| 65 | ifdef(`HAVE_ABI_2_0n', |
| 66 | ` depd %r25,31,32,%r26 |
| 67 | depd %r23,31,32,%r24 |
| 68 | copy %r24,%r25 |
| 69 | ldd -56(%r30),%r24 |
| 70 | ldw -60(%r30),%r23 |
| 71 | ') |
| 72 | ldi 0,q |
| 73 | cmpib,*>= 0,d,L(large_divisor) |
| 74 | ldi 8,%r31 C setup loop counter |
| 75 | |
| 76 | sub %r0,d,dn |
| 77 | LDEF(Loop) |
| 78 | divstep divstep divstep divstep divstep divstep divstep divstep |
| 79 | addib,<> -1,%r31,L(Loop) |
| 80 | nop |
| 81 | |
| 82 | ifdef(`HAVE_ABI_2_0n', |
| 83 | ` copy %r28,%r29 |
| 84 | extrd,u %r28,31,32,%r28 |
| 85 | ') |
| 86 | bve (%r2) |
| 87 | std n1,0(remptr) C store remainder |
| 88 | |
| 89 | LDEF(large_divisor) |
| 90 | extrd,u n0,63,1,%r19 C save lsb of dividend |
| 91 | shrpd n1,n0,1,n0 C n0 = lo(n1n0 >> 1) |
| 92 | shrpd %r0,n1,1,n1 C n1 = hi(n1n0 >> 1) |
| 93 | extrd,u d,63,1,%r20 C save lsb of divisor |
| 94 | shrpd %r0,d,1,d C d = floor(orig_d / 2) |
| 95 | add,l %r20,d,d C d = ceil(orig_d / 2) |
| 96 | |
| 97 | sub %r0,d,dn |
| 98 | LDEF(Loop2) |
| 99 | divstep divstep divstep divstep divstep divstep divstep divstep |
| 100 | addib,<> -1,%r31,L(Loop2) |
| 101 | nop |
| 102 | |
| 103 | cmpib,*= 0,%r20,L(even_divisor) |
| 104 | shladd n1,1,%r19,n1 C shift in omitted dividend lsb |
| 105 | |
| 106 | add d,d,d C restore orig... |
| 107 | sub d,%r20,d C ...d value |
| 108 | sub %r0,d,dn C r21 = -d |
| 109 | |
| 110 | add,*nuv n1,q,n1 C fix remainder for omitted divisor lsb |
| 111 | add,l n1,dn,n1 C adjust remainder if rem. fix carried |
| 112 | add,dc %r0,q,q C adjust quotient accordingly |
| 113 | |
| 114 | sub,*<< n1,d,%r0 C remainder >= divisor? |
| 115 | add,l n1,dn,n1 C adjust remainder |
| 116 | add,dc %r0,q,q C adjust quotient |
| 117 | |
| 118 | LDEF(even_divisor) |
| 119 | ifdef(`HAVE_ABI_2_0n', |
| 120 | ` copy %r28,%r29 |
| 121 | extrd,u %r28,31,32,%r28 |
| 122 | ') |
| 123 | bve (%r2) |
| 124 | std n1,0(remptr) C store remainder |
| 125 | EPILOGUE(mpn_udiv_qrnnd_r) |