/security/nss/lib/freebl/arcfour-amd64-sun.s

  1/ ***** BEGIN LICENSE BLOCK *****
  2/ Version: MPL 1.1/GPL 2.0/LGPL 2.1
  3/
  4/ The contents of this file are subject to the Mozilla Public License Version
  5/ 1.1 (the "License"); you may not use this file except in compliance with
  6/ the License. You may obtain a copy of the License at
  7/ http://www.mozilla.org/MPL/
  8/
  9/ Software distributed under the License is distributed on an "AS IS" basis,
 10/ WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 11/ for the specific language governing rights and limitations under the
 12/ License.
 13/
 14/ The Original Code is "Marc Bevand's fast AMD64 ARCFOUR source"
 15/
 16/ The Initial Developer of the Original Code is
 17/ Marc Bevand <bevand_m@epita.fr> .
 18/ Portions created by the Initial Developer are 
 19/ Copyright (C) 2004 the Initial Developer. All Rights Reserved.
 20/
 21/ Contributor(s):
 22/
 23/ Alternatively, the contents of this file may be used under the terms of
 24/ either the GNU General Public License Version 2 or later (the "GPL"), or
 25/ the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 26/ in which case the provisions of the GPL or the LGPL are applicable instead
 27/ of those above. If you wish to allow use of your version of this file only
 28/ under the terms of either the GPL or the LGPL, and not to allow others to
 29/ use your version of this file under the terms of the MPL, indicate your
 30/ decision by deleting the provisions above and replace them with the notice
 31/ and other provisions required by the GPL or the LGPL. If you do not delete
 32/ the provisions above, a recipient may use your version of this file under
 33/ the terms of any one of the MPL, the GPL or the LGPL.
 34/
 35/ ***** END LICENSE BLOCK *****
 36
 37/ ** ARCFOUR implementation optimized for AMD64.
 38/ **
 39/ ** The throughput achieved by this code is about 320 MBytes/sec, on
 40/ ** a 1.8 GHz AMD Opteron (rev C0) processor.
 41
 42.text
 43.align 16
 44.globl ARCFOUR
 45.type ARCFOUR,@function
 46ARCFOUR:
 47	pushq	%rbp
 48	pushq	%rbx
 49	movq	%rdi,		%rbp	/ key = ARG(key)
 50	movq	%rsi,		%rbx	/ rbx = ARG(len)
 51	movq	%rdx,		%rsi	/ in = ARG(in)
 52	movq	%rcx,		%rdi	/ out = ARG(out)
 53	movq	(%rbp),		%rcx	/ x = key->x
 54	movq	8(%rbp),	%rdx	/ y = key->y
 55	addq	$16,		%rbp	/ d = key->data
 56	incq	%rcx			/ x++
 57	andq	$255,		%rcx	/ x &= 0xff
 58	leaq	-8(%rbx,%rsi),	%rbx	/ rbx = in+len-8
 59	movq	%rbx,		%r9	/ tmp = in+len-8
 60	movq	0(%rbp,%rcx,8),	%rax	/ tx = d[x]
 61	cmpq	%rsi,		%rbx	/ cmp in with in+len-8
 62	jl	.Lend			/ jump if (in+len-8 < in)
 63
 64.Lstart:
 65	addq	$8,		%rsi		/ increment in
 66	addq	$8,		%rdi		/ increment out
 67
 68	/ generate the next 8 bytes of the rc4 stream into %r8
 69	movq	$8,		%r11		/ byte counter
 701:	addb	%al,		%dl		/ y += tx
 71	movl	0(%rbp,%rdx,8),	%ebx		/ ty = d[y]
 72	movl	%ebx,		0(%rbp,%rcx,8)	/ d[x] = ty
 73	addb	%al,		%bl		/ val = ty + tx
 74	movl	%eax,		0(%rbp,%rdx,8)	/ d[y] = tx
 75	incb	%cl				/ x++		(NEXT ROUND)
 76	movl	0(%rbp,%rcx,8),	%eax		/ tx = d[x]	(NEXT ROUND)
 77	movb	0(%rbp,%rbx,8),	%r8b		/ val = d[val]
 78	decb	%r11b
 79	rorq	$8,		%r8		/ (ror does not change ZF)
 80	jnz 	1b
 81
 82	/ xor 8 bytes
 83	xorq	-8(%rsi),	%r8
 84	cmpq	%r9,		%rsi		/ cmp in+len-8 with in
 85	movq	%r8,		-8(%rdi)
 86	jle	.Lstart				/ jump if (in <= in+len-8)
 87
 88.Lend:
 89	addq	$8,		%r9		/ tmp = in+len
 90
 91	/ handle the last bytes, one by one
 921:	cmpq	%rsi,		%r9		/ cmp in with in+len
 93	jle	.Lfinished			/ jump if (in+len <= in)
 94	addb	%al,		%dl		/ y += tx
 95	movl	0(%rbp,%rdx,8),	%ebx		/ ty = d[y]
 96	movl	%ebx,		0(%rbp,%rcx,8)	/ d[x] = ty
 97	addb	%al,		%bl		/ val = ty + tx
 98	movl	%eax,		0(%rbp,%rdx,8)	/ d[y] = tx
 99	incb	%cl				/ x++		(NEXT ROUND)
100	movl	0(%rbp,%rcx,8),	%eax		/ tx = d[x]	(NEXT ROUND)
101	movb	0(%rbp,%rbx,8),	%r8b		/ val = d[val]
102	xorb	(%rsi),		%r8b		/ xor 1 byte
103	movb	%r8b,		(%rdi)
104	incq	%rsi				/ in++
105	incq	%rdi				/ out++
106	jmp 1b
107
108.Lfinished:
109	decq	%rcx				/ x--
110	movb	%dl,		-8(%rbp)	/ key->y = y
111	movb	%cl,		-16(%rbp)	/ key->x = x
112	popq	%rbx
113	popq	%rbp
114	ret
115.L_ARCFOUR_end:
116.size ARCFOUR,.L_ARCFOUR_end-ARCFOUR