1dnl  MIPS64 mpn_submul_1 -- Multiply a limb vector with a single limb and
2dnl  subtract the product from a second limb vector.
3
4dnl  Copyright 1992, 1994, 1995, 2000-2002 Free Software Foundation, Inc.
5
6dnl  This file is part of the GNU MP Library.
7dnl
8dnl  The GNU MP Library is free software; you can redistribute it and/or modify
9dnl  it under the terms of either:
10dnl
11dnl    * the GNU Lesser General Public License as published by the Free
12dnl      Software Foundation; either version 3 of the License, or (at your
13dnl      option) any later version.
14dnl
15dnl  or
16dnl
17dnl    * the GNU General Public License as published by the Free Software
18dnl      Foundation; either version 2 of the License, or (at your option) any
19dnl      later version.
20dnl
21dnl  or both in parallel, as here.
22dnl
23dnl  The GNU MP Library is distributed in the hope that it will be useful, but
24dnl  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
25dnl  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
26dnl  for more details.
27dnl
28dnl  You should have received copies of the GNU General Public License and the
29dnl  GNU Lesser General Public License along with the GNU MP Library.  If not,
30dnl  see https://www.gnu.org/licenses/.
31
32include(`../config.m4')
33
34C INPUT PARAMETERS
35C res_ptr	$4
36C s1_ptr	$5
37C size		$6
38C s2_limb	$7
39
40ASM_START()
41PROLOGUE(mpn_submul_1)
42
43C feed-in phase 0
44	ld	$8,0($5)
45
46C feed-in phase 1
47	daddiu	$5,$5,8
48	dmultu	$8,$7
49
50	daddiu	$6,$6,-1
51	beq	$6,$0,$LC0
52	 move	$2,$0		C zero cy2
53
54	daddiu	$6,$6,-1
55	beq	$6,$0,$LC1
56	ld	$8,0($5)	C load new s1 limb as early as possible
57
58Loop:	ld	$10,0($4)
59	mflo	$3
60	mfhi	$9
61	daddiu	$5,$5,8
62	daddu	$3,$3,$2	C add old carry limb to low product limb
63	dmultu	$8,$7
64	ld	$8,0($5)	C load new s1 limb as early as possible
65	daddiu	$6,$6,-1	C decrement loop counter
66	sltu	$2,$3,$2	C carry from previous addition -> $2
67	dsubu	$3,$10,$3
68	sgtu	$10,$3,$10
69	daddu	$2,$2,$10
70	sd	$3,0($4)
71	daddiu	$4,$4,8
72	bne	$6,$0,Loop
73	 daddu	$2,$9,$2	C add high product limb and carry from addition
74
75C wind-down phase 1
76$LC1:	ld	$10,0($4)
77	mflo	$3
78	mfhi	$9
79	daddu	$3,$3,$2
80	sltu	$2,$3,$2
81	dmultu	$8,$7
82	dsubu	$3,$10,$3
83	sgtu	$10,$3,$10
84	daddu	$2,$2,$10
85	sd	$3,0($4)
86	daddiu	$4,$4,8
87	daddu	$2,$9,$2	C add high product limb and carry from addition
88
89C wind-down phase 0
90$LC0:	ld	$10,0($4)
91	mflo	$3
92	mfhi	$9
93	daddu	$3,$3,$2
94	sltu	$2,$3,$2
95	dsubu	$3,$10,$3
96	sgtu	$10,$3,$10
97	daddu	$2,$2,$10
98	sd	$3,0($4)
99	j	$31
100	daddu	$2,$9,$2	C add high product limb and carry from addition
101EPILOGUE(mpn_submul_1)
102