SHA256SU1

SHA-256 schedule update 1

SHA-256 schedule update 1.

Advanced SIMD
(FEAT_SHA256)

313029282726252423222120191817161514131211109876543210
01011110000Rm011000RnRd
sizeopcode

Encoding

SHA256SU1 <Vd>.4S, <Vn>.4S, <Vm>.4S

Decode for this encoding

if !IsFeatureImplemented(FEAT_SHA256) then EndOfDecode(Decode_UNDEF); end; let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn); let m : integer{} = UInt(Rm);

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.

<Vm>

Is the name of the third SIMD&FP source register, encoded in the "Rm" field.

Operation

AArch64_CheckFPAdvSIMDEnabled(); let operand1 : bits(128) = V{}(d); let operand2 : bits(128) = V{}(n); let operand3 : bits(128) = V{}(m); let T0 : bits(128) = operand3[31:0] :: operand2[127:32]; var T1 : bits(64); var elt : bits(32); var result : bits(128); T1 = operand3[127:64]; for e = 0 to 1 do elt = T1[e*:32]; elt = ROR(elt, 17) XOR ROR(elt, 19) XOR LSR(elt, 10); elt = elt + operand1[e*:32] + T0[e*:32]; result[e*:32] = elt; end; T1 = result[63:0]; for e = 2 to 3 do elt = T1[(e - 2)*:32]; elt = ROR(elt, 17) XOR ROR(elt, 19) XOR LSR(elt, 10); elt = elt + operand1[e*:32] + T0[e*:32]; result[e*:32] = elt; end; 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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