Commit 64333004 authored by Andy Polyakov's avatar Andy Polyakov
Browse files

ec/asm/ecp_nistz256-x86_64.pl: get corner case logic right. 



RT#4284

Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
(cherry picked from commit d9375341)
parent 04f2a0b5

crypto/ec/asm/ecp_nistz256-x86_64.pl

+10 −1
Original line number Diff line number Diff line
@@ -2001,6 +2001,7 @@ $code.=<<___; 
	push	%r15

	sub	\$32*5+8, %rsp



.Lpoint_double_shortcut$x:

	movdqu	0x00($a_ptr), %xmm0		# copy	*(P256_POINT *)$a_ptr.x

	mov	$a_ptr, $b_ptr			# backup copy

	movdqu	0x10($a_ptr), %xmm1
@@ -2291,6 +2292,7 @@ $code.=<<___; 
	 mov	0x40+8*1($b_ptr), $acc6

	 mov	0x40+8*2($b_ptr), $acc7

	 mov	0x40+8*3($b_ptr), $acc0

	movq	$b_ptr, %xmm1



	lea	0x40-$bias($b_ptr), $a_ptr

	lea	$Z1sqr(%rsp), $r_ptr		# Z1^2
@@ -2346,7 +2348,7 @@ $code.=<<___; 
	test	$acc0, $acc0

	jnz	.Ladd_proceed$x			# (in1infty || in2infty)?

	test	$acc1, $acc1

	jz	.Ladd_proceed$x			# is_equal(S1,S2)?

	jz	.Ladd_double$x			# is_equal(S1,S2)?



	movq	%xmm0, $r_ptr			# restore $r_ptr

	pxor	%xmm0, %xmm0
@@ -2358,6 +2360,13 @@ $code.=<<___; 
	movdqu	%xmm0, 0x50($r_ptr)

	jmp	.Ladd_done$x



.align	32

.Ladd_double$x:

	movq	%xmm1, $a_ptr			# restore $a_ptr

	movq	%xmm0, $r_ptr			# restore $r_ptr

	add	\$`32*(18-5)`, %rsp		# difference in frame sizes

	jmp	.Lpoint_double_shortcut$x



.align	32

.Ladd_proceed$x:

	`&load_for_sqr("$R(%rsp)", "$src0")`