x86doc › SHA1NEXTE - Calculate SHA1 State Variable E After Four Rounds

SHA1NEXTE—Calculate SHA1 State Variable E After Four Rounds

Opcode/Instruction	Op/En	64/32 bit Mode Support	CPUID Feature Flag	Description
NP 0F 38 C8 /r SHA1NEXTE xmm1, xmm2/m128	RM	V/V	SHA	Calculates SHA1 state variable E after four rounds of operation from the current SHA1 state variable A in xmm1. The calculated value of the SHA1 state variable E is added to the scheduled dwords in xmm2/m128, and stored with some of the scheduled dwords in xmm1.

Instruction Operand Encoding

Op/En	Operand 1	Operand 2	Operand 3
RM	ModRM:reg (r, w)	ModRM:r/m (r)	N/A

Description

The SHA1NEXTE calculates the SHA1 state variable E after four rounds of operation from the current SHA1 state variable A in the destination operand. The calculated value of the SHA1 state variable E is added to the source operand, which contains the scheduled dwords.

Operation

SHA1NEXTE

TMP := (SRC1[127:96] ROL 30);
DEST[127:96] := SRC2[127:96] + TMP;
DEST[95:64] := SRC2[95:64];
DEST[63:32] := SRC2[63:32];
DEST[31:0] := SRC2[31:0];

Intel C/C++ Compiler Intrinsic Equivalent

SHA1NEXTE __m128i _mm_sha1nexte_epu32(__m128i, __m128i);

Flags Affected

None.

SIMD Floating-Point Exceptions

None.

Other Exceptions

See Table 2-21, “Type 4 Class Exception Conditions.”