1dnl  S/390-64 mpn_sublsh1_n
2
3dnl  Copyright 2011 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 z900		10
35C z990		 5
36C z9		 ?
37C z10		12
38C z196		 ?
39
40C TODO
41C  * Optimise for small n
42C  * Compute RETVAL for sublsh1_n less stupidly
43
44C INPUT PARAMETERS
45define(`rp',	`%r2')
46define(`up',	`%r3')
47define(`vp',	`%r4')
48define(`n',	`%r5')
49
50ifdef(`OPERATION_addlsh1_n',`
51  define(ADSBR,		algr)
52  define(ADSBCR,	alcgr)
53  define(INITCY,	`lghi	%r13, -1')
54  define(RETVAL,	`la	%r2, 2(%r1,%r13)')
55  define(func, mpn_addlsh1_n)
56')
57ifdef(`OPERATION_sublsh1_n',`
58  define(ADSBR,		slgr)
59  define(ADSBCR,	slbgr)
60  define(INITCY,	`lghi	%r13, 0')
61  define(RETVAL,`dnl
62	slgr	%r1, %r13
63	lghi	%r2, 1
64	algr	%r2, %r1')
65  define(func, mpn_sublsh1_n)
66')
67
68ASM_START()
69PROLOGUE(mpn_sublsh1_n)
70	stmg	%r6, %r13, 48(%r15)
71
72	aghi	n, 3
73	lghi	%r7, 3
74	srlg	%r0, n, 2
75	ngr	%r7, n			C n mod 4
76	je	L(b1)
77	cghi	%r7, 2
78	jl	L(b2)
79	jne	L(b0)
80
81L(b3):	lmg	%r5, %r7, 0(up)
82	la	up, 24(up)
83	lmg	%r9, %r11, 0(vp)
84	la	vp, 24(vp)
85
86	algr	%r9, %r9
87	alcgr	%r10, %r10
88	alcgr	%r11, %r11
89	slbgr	%r1, %r1
90
91	ADSBR	%r5, %r9
92	ADSBCR	%r6, %r10
93	ADSBCR	%r7, %r11
94	slbgr	%r13, %r13
95
96	stmg	%r5, %r7, 0(rp)
97	la	rp, 24(rp)
98	brctg	%r0, L(top)
99	j	L(end)
100
101L(b0):	lghi	%r1, -1
102	INITCY
103	j	L(top)
104
105L(b1):	lg	%r5, 0(up)
106	la	up, 8(up)
107	lg	%r9, 0(vp)
108	la	vp, 8(vp)
109
110	algr	%r9, %r9
111	slbgr	%r1, %r1
112	ADSBR	%r5, %r9
113	slbgr	%r13, %r13
114
115	stg	%r5, 0(rp)
116	la	rp, 8(rp)
117	brctg	%r0, L(top)
118	j	L(end)
119
120L(b2):	lmg	%r5, %r6, 0(up)
121	la	up, 16(up)
122	lmg	%r9, %r10, 0(vp)
123	la	vp, 16(vp)
124
125	algr	%r9, %r9
126	alcgr	%r10, %r10
127	slbgr	%r1, %r1
128
129	ADSBR	%r5, %r9
130	ADSBCR	%r6, %r10
131	slbgr	%r13, %r13
132
133	stmg	%r5, %r6, 0(rp)
134	la	rp, 16(rp)
135	brctg	%r0, L(top)
136	j	L(end)
137
138L(top):	lmg	%r9, %r12, 0(vp)
139	la	vp, 32(vp)
140
141	aghi	%r1, 1			C restore carry
142
143	alcgr	%r9, %r9
144	alcgr	%r10, %r10
145	alcgr	%r11, %r11
146	alcgr	%r12, %r12
147
148	slbgr	%r1, %r1		C save carry
149
150	lmg	%r5, %r8, 0(up)
151	la	up, 32(up)
152
153	aghi	%r13, 1			C restore carry
154
155	ADSBCR	%r5, %r9
156	ADSBCR	%r6, %r10
157	ADSBCR	%r7, %r11
158	ADSBCR	%r8, %r12
159
160	slbgr	%r13, %r13		C save carry
161
162	stmg	%r5, %r8, 0(rp)
163	la	rp, 32(rp)
164	brctg	%r0, L(top)
165
166L(end):	RETVAL
167	lmg	%r6, %r13, 48(%r15)
168	br	%r14
169EPILOGUE()
170