1dnl  PowerPC-64 mpn_modexact_1_odd -- mpn by limb exact remainder.
2
3dnl  Copyright 2006 Free Software Foundation, Inc.
4
5dnl  This file is part of the GNU MP Library.
6dnl
7dnl  The GNU MP Library is free software; you can redistribute it and/or modify
8dnl  it under the terms of either:
9dnl
10dnl    * the GNU Lesser General Public License as published by the Free
11dnl      Software Foundation; either version 3 of the License, or (at your
12dnl      option) any later version.
13dnl
14dnl  or
15dnl
16dnl    * the GNU General Public License as published by the Free Software
17dnl      Foundation; either version 2 of the License, or (at your option) any
18dnl      later version.
19dnl
20dnl  or both in parallel, as here.
21dnl
22dnl  The GNU MP Library is distributed in the hope that it will be useful, but
23dnl  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
24dnl  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
25dnl  for more details.
26dnl
27dnl  You should have received copies of the GNU General Public License and the
28dnl  GNU Lesser General Public License along with the GNU MP Library.  If not,
29dnl  see https://www.gnu.org/licenses/.
30
31include(`../config.m4')
32
33C                  cycles/limb
34C POWER3/PPC630        13-19
35C POWER4/PPC970         16
36C POWER5                16
37C POWER6                 ?
38C POWER7                12
39
40C TODO
41C  * Check if n=1 code is really an improvement.  It probably isn't.
42C  * Make more similar to dive_1.asm.
43
44C INPUT PARAMETERS
45define(`up', `r3')
46define(`n',  `r4')
47define(`d',  `r5')
48define(`cy', `r6')
49
50
51ASM_START()
52
53EXTERN(binvert_limb_table)
54
55PROLOGUE(mpn_modexact_1c_odd,toc)
56          addic.    n, n, -1            C set carry as side effect
57          ld        r8, 0(up)
58          bne       cr0, L(2)
59          cmpld     cr7, r6, r8
60          bge       cr7, L(4)
61          subf      r8, r6, r8
62          divdu     r3, r8, d
63          mulld     r3, r3, d
64          subf.     r3, r3, r8
65          beqlr     cr0
66          subf      r3, r3, d
67          blr
68
69L(4):     subf      r3, r8, r6
70          divdu     r8, r3, d
71          mulld     r8, r8, d
72          subf      r3, r8, r3
73          blr
74
75L(2):     LEA(      r7, binvert_limb_table)
76          rldicl    r9, d, 63, 57
77          mtctr     n
78          lbzx      r0, r7, r9
79          mulld     r7, r0, r0
80          sldi      r0, r0, 1
81          mulld     r7, d, r7
82          subf      r0, r7, r0
83          mulld     r9, r0, r0
84          sldi      r0, r0, 1
85          mulld     r9, d, r9
86          subf      r0, r9, r0
87          mulld     r7, r0, r0
88          sldi      r0, r0, 1
89          mulld     r7, d, r7
90          subf      r9, r7, r0
91
92          ALIGN(16)
93L(loop):
94          subfe     r0, r6, r8
95          ld        r8, 8(up)
96          addi      up, up, 8
97          mulld     r0, r9, r0
98          mulhdu    r6, r0, d
99          bdnz      L(loop)
100
101          cmpld     cr7, d, r8
102          blt       cr7, L(10)
103
104          subfe     r0, r0, r0
105          subf      r6, r0, r6
106          cmpld     cr7, r6, r8
107          subf      r3, r8, r6
108          bgelr     cr7
109          add       r3, d, r3
110          blr
111
112L(10):    subfe     r0, r6, r8
113          mulld     r0, r9, r0
114          mulhdu    r3, r0, d
115          blr
116EPILOGUE()
117ASM_END()
118