xref: /netbsd-src/external/lgpl3/gmp/dist/mpn/x86/pentium4/sse2/popcount.asm (revision 72c7faa4dbb41dbb0238d6b4a109da0d4b236dd4)
1dnl  X86-32 and X86-64 mpn_popcount using SSE2.
2
3dnl  Copyright 2006, 2007, 2011, 2015, 2020 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
31
32include(`../config.m4')
33
34
35C 32-bit		     popcount	     hamdist
36C			    cycles/limb	    cycles/limb
37C P5				-
38C P6 model 0-8,10-12		-
39C P6 model 9  (Banias)		?
40C P6 model 13 (Dothan)		4
41C P4 model 0  (Willamette)	?
42C P4 model 1  (?)		?
43C P4 model 2  (Northwood)	3.9
44C P4 model 3  (Prescott)	?
45C P4 model 4  (Nocona)		?
46C AMD K6			-
47C AMD K7			-
48C AMD K8			?
49
50C 64-bit		     popcount	     hamdist
51C			    cycles/limb	    cycles/limb
52C P4 model 4 (Nocona):		8
53C AMD K8,K9			7.5
54C AMD K10			3.5
55C Intel core2			3.68
56C Intel corei			3.15
57C Intel atom		       10.8
58C VIA nano			6.5
59
60C TODO
61C  * Make an mpn_hamdist based on this.  Alignment could either be handled by
62C    using movdqu for one operand and movdqa for the other, or by painfully
63C    shifting as we go.  Unfortunately, there seem to be no usable shift
64C    instruction, except for one that takes an immediate count.
65C  * It would probably be possible to cut a few cycles/limb using software
66C    pipelining.
67C  * There are 35 decode slots unused by the SSE2 instructions.  Loop control
68C    needs just 2 or 3 slots, leaving around 32 slots.  This allows a parallel
69C    integer based popcount.  Such a combined loop would handle 6 limbs in
70C    about 30 cycles on K8.
71C  * We could save a byte or two by using 32-bit operations on areg.
72C  * Check if using movdqa to a temp of and then register-based pand is faster.
73
74ifelse(GMP_LIMB_BITS,`32',
75`	define(`up',  `%edx')
76	define(`n',   `%ecx')
77	define(`areg',`%eax')
78	define(`breg',`%ebx')
79	define(`zero',`%xmm4')
80	define(`LIMB32',`	$1')
81	define(`LIMB64',`dnl')
82',`
83	define(`up',  `%rdi')
84	define(`n',   `%rsi')
85	define(`areg',`%rax')
86	define(`breg',`%rdx')
87	define(`zero',`%xmm8')
88	define(`LIMB32',`dnl')
89	define(`LIMB64',`	$1')
90')
91
92define(`mm01010101',`%xmm6')
93define(`mm00110011',`%xmm7')
94define(`mm00001111',`%xmm2')
95
96define(`GMP_LIMB_BYTES', eval(GMP_LIMB_BITS/8))
97define(`LIMBS_PER_XMM',  eval(16/GMP_LIMB_BYTES))
98define(`LIMBS_PER_2XMM', eval(32/GMP_LIMB_BYTES))
99
100undefine(`psadbw')			C override inherited m4 version
101
102C This file is shared between 32-bit and 64-bit builds.  Only the former has
103C LEAL.  Default LEAL as an alias of LEA.
104ifdef(`LEAL',,`define(`LEAL', `LEA($1,$2)')')
105
106ASM_START()
107
108C Make cnsts global to work around Apple relocation bug.
109ifdef(`DARWIN',`
110	define(`cnsts', MPN(popccnsts))
111	GLOBL	cnsts')
112
113	TEXT
114	ALIGN(32)
115PROLOGUE(mpn_popcount)
116
117LIMB32(`mov	4(%esp), up	')
118LIMB32(`mov	8(%esp), n	')
119LIMB32(`push	%ebx		')
120
121	pxor	%xmm3, %xmm3		C zero grand total count
122LIMB64(`pxor	zero, zero	')
123
124	LEAL(	cnsts, breg)
125
126	movdqa	-48(breg), mm01010101
127	movdqa	-32(breg), mm00110011
128	movdqa	-16(breg), mm00001111
129
130	mov	up, areg
131	and	$-16, up		C round `up' down to 128-bit boundary
132	and	$12, areg		C 32:areg = 0, 4, 8, 12
133					C 64:areg = 0, 8
134	movdqa	(up), %xmm0
135	pand	64(breg,areg,4), %xmm0
136	shr	$m4_log2(GMP_LIMB_BYTES), %eax
137	add	areg, n			C compensate n for rounded down `up'
138
139	pxor	%xmm4, %xmm4
140	sub	$LIMBS_PER_XMM, n
141	jbe	L(sum)
142
143	sub	$LIMBS_PER_XMM, n
144	ja	L(ent)
145	jmp	L(lsum)
146
147	ALIGN(16)
148L(top):	movdqa	(up), %xmm0
149L(ent):	movdqa	16(up), %xmm4
150
151	movdqa	%xmm0, %xmm1
152	movdqa	%xmm4, %xmm5
153	psrld	$1, %xmm0
154	psrld	$1, %xmm4
155	pand	mm01010101, %xmm0
156	pand	mm01010101, %xmm4
157	psubd	%xmm0, %xmm1
158	psubd	%xmm4, %xmm5
159
160	movdqa	%xmm1, %xmm0
161	movdqa	%xmm5, %xmm4
162	psrlq	$2, %xmm1
163	psrlq	$2, %xmm5
164	pand	mm00110011, %xmm0
165	pand	mm00110011, %xmm4
166	pand	mm00110011, %xmm1
167	pand	mm00110011, %xmm5
168	paddq	%xmm0, %xmm1
169	paddq	%xmm4, %xmm5
170
171LIMB32(`pxor	zero, zero	')
172
173	add	$32, up
174	sub	$LIMBS_PER_2XMM, n
175
176	paddq	%xmm5, %xmm1
177	movdqa	%xmm1, %xmm0
178	psrlq	$4, %xmm1
179	pand	mm00001111, %xmm0
180	pand	mm00001111, %xmm1
181	paddq	%xmm0, %xmm1
182
183	psadbw	zero, %xmm1
184	paddq	%xmm1, %xmm3		C add to grand total
185
186	jnc	L(top)
187L(end):
188	add	$LIMBS_PER_2XMM, n
189	jz	L(rt)
190	movdqa	(up), %xmm0
191	pxor	%xmm4, %xmm4
192	sub	$LIMBS_PER_XMM, n
193	jbe	L(sum)
194L(lsum):
195	movdqa	%xmm0, %xmm4
196	movdqa	16(up), %xmm0
197L(sum):
198	shl	$m4_log2(GMP_LIMB_BYTES), n
199	and	$12, n
200	pand	(breg,n,4), %xmm0
201
202	movdqa	%xmm0, %xmm1
203	movdqa	%xmm4, %xmm5
204	psrld	$1, %xmm0
205	psrld	$1, %xmm4
206	pand	mm01010101, %xmm0
207	pand	mm01010101, %xmm4
208	psubd	%xmm0, %xmm1
209	psubd	%xmm4, %xmm5
210
211	movdqa	%xmm1, %xmm0
212	movdqa	%xmm5, %xmm4
213	psrlq	$2, %xmm1
214	psrlq	$2, %xmm5
215	pand	mm00110011, %xmm0
216	pand	mm00110011, %xmm4
217	pand	mm00110011, %xmm1
218	pand	mm00110011, %xmm5
219	paddq	%xmm0, %xmm1
220	paddq	%xmm4, %xmm5
221
222LIMB32(`pxor	zero, zero	')
223
224	paddq	%xmm5, %xmm1
225	movdqa	%xmm1, %xmm0
226	psrlq	$4, %xmm1
227	pand	mm00001111, %xmm0
228	pand	mm00001111, %xmm1
229	paddq	%xmm0, %xmm1
230
231	psadbw	zero, %xmm1
232	paddq	%xmm1, %xmm3		C add to grand total
233
234
235C Add the two 64-bit halves of the grand total counter
236L(rt):	movdqa	%xmm3, %xmm0
237	psrldq	$8, %xmm3
238	paddq	%xmm3, %xmm0
239	movd	%xmm0, areg		C movq avoided due to gas bug
240
241LIMB32(`pop	%ebx		')
242	ret
243
244EPILOGUE()
245DEF_OBJECT(dummy,16)
246C Three magic constants used for masking out bits
247	.byte	0x55,0x55,0x55,0x55,0x55,0x55,0x55,0x55
248	.byte	0x55,0x55,0x55,0x55,0x55,0x55,0x55,0x55
249
250	.byte	0x33,0x33,0x33,0x33,0x33,0x33,0x33,0x33
251	.byte	0x33,0x33,0x33,0x33,0x33,0x33,0x33,0x33
252
253	.byte	0x0f,0x0f,0x0f,0x0f,0x0f,0x0f,0x0f,0x0f
254	.byte	0x0f,0x0f,0x0f,0x0f,0x0f,0x0f,0x0f,0x0f
255cnsts:
256C Masks for high end of number
257	.byte	0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff
258	.byte	0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff
259
260	.byte	0xff,0xff,0xff,0xff,0x00,0x00,0x00,0x00
261	.byte	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
262
263	.byte	0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff
264	.byte	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
265
266	.byte	0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff
267	.byte	0xff,0xff,0xff,0xff,0x00,0x00,0x00,0x00
268C Masks for low end of number
269	.byte	0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff
270	.byte	0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff
271
272	.byte	0x00,0x00,0x00,0x00,0xff,0xff,0xff,0xff
273	.byte	0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff
274
275	.byte	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
276	.byte	0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff
277
278	.byte	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
279	.byte	0x00,0x00,0x00,0x00,0xff,0xff,0xff,0xff
280END_OBJECT(dummy)
281ASM_END()
282