SHA1SU1

SHA1 schedule update 1

SHA1 schedule update 1.

Advanced SIMD
(FEAT_SHA1)

313029282726252423222120191817161514131211109876543210
0101111000101000000110RnRd
sizeopcode

Encoding

SHA1SU1 <Vd>.4S, <Vn>.4S

Decode for this encoding

if !IsFeatureImplemented(FEAT_SHA1) then EndOfDecode(Decode_UNDEF); end; let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn);

Assembler Symbols

<Vd>

Is the name of the SIMD&FP source and destination register, encoded in the "Rd" field.

<Vn>

Is the name of the second SIMD&FP source register, encoded in the "Rn" field.

Operation

AArch64_CheckFPAdvSIMDEnabled(); let operand1 : bits(128) = V{}(d); let operand2 : bits(128) = V{}(n); let T : bits(128) = operand1 XOR LSR(operand2, 32); var result : bits(128); result[31:0] = ROL(T[31:0], 1); result[63:32] = ROL(T[63:32], 1); result[95:64] = ROL(T[95:64], 1); result[127:96] = ROL(T[127:96], 1) XOR ROL(T[31:0], 2); V{128}(d) = result;

Operational information

This instruction is a data-independent-time instruction as described in About PSTATE.DIT.


2026-03_rel 2026-03-26 20:48:11

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