import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

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

@@ -0,0 +1,84 @@
+/ This Source Code Form is subject to the terms of the Mozilla Public
+/ License, v. 2.0. If a copy of the MPL was not distributed with this
+/ file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+/ ** ARCFOUR implementation optimized for AMD64.
+/ **
+/ ** The throughput achieved by this code is about 320 MBytes/sec, on
+/ ** a 1.8 GHz AMD Opteron (rev C0) processor.
+
+.text
+.align 16
+.globl ARCFOUR
+.type ARCFOUR,@function
+ARCFOUR:
+	pushq	%rbp
+	pushq	%rbx
+	movq	%rdi,		%rbp	/ key = ARG(key)
+	movq	%rsi,		%rbx	/ rbx = ARG(len)
+	movq	%rdx,		%rsi	/ in = ARG(in)
+	movq	%rcx,		%rdi	/ out = ARG(out)
+	movq	(%rbp),		%rcx	/ x = key->x
+	movq	8(%rbp),	%rdx	/ y = key->y
+	addq	$16,		%rbp	/ d = key->data
+	incq	%rcx			/ x++
+	andq	$255,		%rcx	/ x &= 0xff
+	leaq	-8(%rbx,%rsi),	%rbx	/ rbx = in+len-8
+	movq	%rbx,		%r9	/ tmp = in+len-8
+	movq	0(%rbp,%rcx,8),	%rax	/ tx = d[x]
+	cmpq	%rsi,		%rbx	/ cmp in with in+len-8
+	jl	.Lend			/ jump if (in+len-8 < in)
+
+.Lstart:
+	addq	$8,		%rsi		/ increment in
+	addq	$8,		%rdi		/ increment out
+
+	/ generate the next 8 bytes of the rc4 stream into %r8
+	movq	$8,		%r11		/ byte counter
+1:	addb	%al,		%dl		/ y += tx
+	movl	0(%rbp,%rdx,8),	%ebx		/ ty = d[y]
+	movl	%ebx,		0(%rbp,%rcx,8)	/ d[x] = ty
+	addb	%al,		%bl		/ val = ty + tx
+	movl	%eax,		0(%rbp,%rdx,8)	/ d[y] = tx
+	incb	%cl				/ x++		(NEXT ROUND)
+	movl	0(%rbp,%rcx,8),	%eax		/ tx = d[x]	(NEXT ROUND)
+	movb	0(%rbp,%rbx,8),	%r8b		/ val = d[val]
+	decb	%r11b
+	rorq	$8,		%r8		/ (ror does not change ZF)
+	jnz 	1b
+
+	/ xor 8 bytes
+	xorq	-8(%rsi),	%r8
+	cmpq	%r9,		%rsi		/ cmp in+len-8 with in
+	movq	%r8,		-8(%rdi)
+	jle	.Lstart				/ jump if (in <= in+len-8)
+
+.Lend:
+	addq	$8,		%r9		/ tmp = in+len
+
+	/ handle the last bytes, one by one
+1:	cmpq	%rsi,		%r9		/ cmp in with in+len
+	jle	.Lfinished			/ jump if (in+len <= in)
+	addb	%al,		%dl		/ y += tx
+	movl	0(%rbp,%rdx,8),	%ebx		/ ty = d[y]
+	movl	%ebx,		0(%rbp,%rcx,8)	/ d[x] = ty
+	addb	%al,		%bl		/ val = ty + tx
+	movl	%eax,		0(%rbp,%rdx,8)	/ d[y] = tx
+	incb	%cl				/ x++		(NEXT ROUND)
+	movl	0(%rbp,%rcx,8),	%eax		/ tx = d[x]	(NEXT ROUND)
+	movb	0(%rbp,%rbx,8),	%r8b		/ val = d[val]
+	xorb	(%rsi),		%r8b		/ xor 1 byte
+	movb	%r8b,		(%rdi)
+	incq	%rsi				/ in++
+	incq	%rdi				/ out++
+	jmp 1b
+
+.Lfinished:
+	decq	%rcx				/ x--
+	movb	%dl,		-8(%rbp)	/ key->y = y
+	movb	%cl,		-16(%rbp)	/ key->x = x
+	popq	%rbx
+	popq	%rbp
+	ret
+.L_ARCFOUR_end:
+.size ARCFOUR,.L_ARCFOUR_end-ARCFOUR