busybox/libbb/hash_sha1_hwaccel_x86-32.S

#if ENABLE_SHA1_HWACCEL && defined(__GNUC__) && defined(__i386__)
/* The code is adapted from Linux kernel's source */

// We use shorter insns, even though they are for "wrong"
// data type (fp, not int).
// For Intel, there is no penalty for doing it at all
// (CPUs which do have such penalty do not support SHA insns).
// For AMD, the penalty is one extra cycle
// (allegedly: I failed to find measurable difference).

//#define mova128 movdqa
#define mova128 movaps
//#define movu128 movdqu
#define movu128 movups
//#define xor128 pxor
#define xor128 xorps
//#define shuf128_32 pshufd
#define shuf128_32 shufps

#define extr128_32 pextrd
//#define extr128_32 extractps	# not shorter

// pshufb is a SSSE3 insn.
// pinsrd, pextrd, extractps are SSE4.1 insns.
// We do not check SSSE3/SSE4.1 in cpuid,
// all SHA-capable CPUs support them as well.

#ifdef __linux__
	.section	.note.GNU-stack, "", @progbits
#endif
	.section	.text.sha1_process_block64_shaNI, "ax", @progbits
	.globl	sha1_process_block64_shaNI
	.hidden	sha1_process_block64_shaNI
	.type	sha1_process_block64_shaNI, @function

#define ABCD		%xmm0
#define E0		%xmm1	/* Need two E's b/c they ping pong */
#define E1		%xmm2
#define MSG0		%xmm3
#define MSG1		%xmm4
#define MSG2		%xmm5
#define MSG3		%xmm6

	.balign	8	# allow decoders to fetch at least 2 first insns
sha1_process_block64_shaNI:
	/* load initial hash values */
	movu128		76(%eax), ABCD
	xor128		E0, E0
	pinsrd		$3, 76+4*4(%eax), E0	# load to uppermost 32-bit word
	shuf128_32	$0x1B, ABCD, ABCD	# DCBA -> ABCD

	mova128		PSHUFFLE_BYTE_FLIP_MASK, %xmm7

	movu128		0*16(%eax), MSG0
	pshufb		%xmm7, MSG0
	movu128		1*16(%eax), MSG1
	pshufb		%xmm7, MSG1
	movu128		2*16(%eax), MSG2
	pshufb		%xmm7, MSG2
	movu128		3*16(%eax), MSG3
	pshufb		%xmm7, MSG3

	/* Save hash values for addition after rounds */
	mova128		E0, %xmm7
	/*mova128	ABCD, %xmm8 - NOPE, 32bit has no xmm8 */

	/* Rounds 0-3 */
		paddd		MSG0, E0
		mova128		ABCD, E1
		sha1rnds4	$0, E0, ABCD

	/* Rounds 4-7 */
		sha1nexte	MSG1, E1
		mova128		ABCD, E0
		sha1rnds4	$0, E1, ABCD
	sha1msg1	MSG1, MSG0

	/* Rounds 8-11 */
		sha1nexte	MSG2, E0
		mova128		ABCD, E1
		sha1rnds4	$0, E0, ABCD
	sha1msg1	MSG2, MSG1
	xor128		MSG2, MSG0

	/* Rounds 12-15 */
		sha1nexte	MSG3, E1
		mova128		ABCD, E0
	sha1msg2	MSG3, MSG0
		sha1rnds4	$0, E1, ABCD
	sha1msg1	MSG3, MSG2
	xor128		MSG3, MSG1

	/* Rounds 16-19 */
		sha1nexte	MSG0, E0
		mova128		ABCD, E1
	sha1msg2	MSG0, MSG1
		sha1rnds4	$0, E0, ABCD
	sha1msg1	MSG0, MSG3
	xor128		MSG0, MSG2

	/* Rounds 20-23 */
		sha1nexte	MSG1, E1
		mova128		ABCD, E0
	sha1msg2	MSG1, MSG2
		sha1rnds4	$1, E1, ABCD
	sha1msg1	MSG1, MSG0
	xor128		MSG1, MSG3

	/* Rounds 24-27 */
		sha1nexte	MSG2, E0
		mova128		ABCD, E1
	sha1msg2	MSG2, MSG3
		sha1rnds4	$1, E0, ABCD
	sha1msg1	MSG2, MSG1
	xor128		MSG2, MSG0

	/* Rounds 28-31 */
		sha1nexte	MSG3, E1
		mova128		ABCD, E0
	sha1msg2	MSG3, MSG0
		sha1rnds4	$1, E1, ABCD
	sha1msg1	MSG3, MSG2
	xor128		MSG3, MSG1

	/* Rounds 32-35 */
		sha1nexte	MSG0, E0
		mova128		ABCD, E1
	sha1msg2	MSG0, MSG1
		sha1rnds4	$1, E0, ABCD
	sha1msg1	MSG0, MSG3
	xor128		MSG0, MSG2

	/* Rounds 36-39 */
		sha1nexte	MSG1, E1
		mova128		ABCD, E0
	sha1msg2	MSG1, MSG2
		sha1rnds4	$1, E1, ABCD
	sha1msg1	MSG1, MSG0
	xor128		MSG1, MSG3

	/* Rounds 40-43 */
		sha1nexte	MSG2, E0
		mova128		ABCD, E1
	sha1msg2	MSG2, MSG3
		sha1rnds4	$2, E0, ABCD
	sha1msg1	MSG2, MSG1
	xor128		MSG2, MSG0

	/* Rounds 44-47 */
		sha1nexte	MSG3, E1
		mova128		ABCD, E0
	sha1msg2	MSG3, MSG0
		sha1rnds4	$2, E1, ABCD
	sha1msg1	MSG3, MSG2
	xor128		MSG3, MSG1

	/* Rounds 48-51 */
		sha1nexte	MSG0, E0
		mova128		ABCD, E1
	sha1msg2	MSG0, MSG1
		sha1rnds4	$2, E0, ABCD
	sha1msg1	MSG0, MSG3
	xor128		MSG0, MSG2

	/* Rounds 52-55 */
		sha1nexte	MSG1, E1
		mova128		ABCD, E0
	sha1msg2	MSG1, MSG2
		sha1rnds4	$2, E1, ABCD
	sha1msg1	MSG1, MSG0
	xor128		MSG1, MSG3

	/* Rounds 56-59 */
		sha1nexte	MSG2, E0
		mova128		ABCD, E1
	sha1msg2	MSG2, MSG3
		sha1rnds4	$2, E0, ABCD
	sha1msg1	MSG2, MSG1
	xor128		MSG2, MSG0

	/* Rounds 60-63 */
		sha1nexte	MSG3, E1
		mova128		ABCD, E0
	sha1msg2	MSG3, MSG0
		sha1rnds4	$3, E1, ABCD
	sha1msg1	MSG3, MSG2
	xor128		MSG3, MSG1

	/* Rounds 64-67 */
		sha1nexte	MSG0, E0
		mova128		ABCD, E1
	sha1msg2	MSG0, MSG1
		sha1rnds4	$3, E0, ABCD
	sha1msg1	MSG0, MSG3
	xor128		MSG0, MSG2

	/* Rounds 68-71 */
		sha1nexte	MSG1, E1
		mova128		ABCD, E0
	sha1msg2	MSG1, MSG2
		sha1rnds4	$3, E1, ABCD
	xor128		MSG1, MSG3

	/* Rounds 72-75 */
		sha1nexte	MSG2, E0
		mova128		ABCD, E1
	sha1msg2	MSG2, MSG3
		sha1rnds4	$3, E0, ABCD

	/* Rounds 76-79 */
		sha1nexte	MSG3, E1
		mova128		ABCD, E0
		sha1rnds4	$3, E1, ABCD

	/* Add current hash values with previously saved */
	sha1nexte	%xmm7, E0
	/*paddd		%xmm8, ABCD - 32-bit mode has no xmm8 */
	movu128		76(%eax), %xmm7	# get original ABCD (not shuffled)...

	/* Write hash values back in the correct order */
	shuf128_32	$0x1B, ABCD, ABCD
	paddd		%xmm7, ABCD	# ...add it to final ABCD
	movu128		ABCD, 76(%eax)
	extr128_32	$3, E0, 76+4*4(%eax)

	ret
	.size	sha1_process_block64_shaNI, .-sha1_process_block64_shaNI

	.section	.rodata.cst16.PSHUFFLE_BYTE_FLIP_MASK, "aM", @progbits, 16
	.balign	16
PSHUFFLE_BYTE_FLIP_MASK:
	.octa	0x000102030405060708090a0b0c0d0e0f

#endif