SHA1M SHA1 hash update (majority) SHA1 hash update (majority). If PSTATE.DIT is 1: The execution time of this instruction is independent of: The values of the data supplied in any of its registers. The values of the NZCV flags. The response of this instruction to asynchronous exceptions does not vary based on: The values of the data supplied in any of its registers. The values of the NZCV flags. 0 1 0 1 1 1 1 0 0 0 0 0 0 1 0 0 0 SHA1M <Qd>, <Sn>, <Vm>.4S if !IsFeatureImplemented(FEAT_SHA1) then UNDEFINED; constant integer d = UInt(Rd); constant integer n = UInt(Rn); constant integer m = UInt(Rm); <Qd> Is the 128-bit name of the SIMD&FP source and destination, encoded in the "Rd" field. <Sn> Is the 32-bit 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. AArch64.CheckFPAdvSIMDEnabled(); bits(128) x = V[d, 128]; bits(32) y = V[n, 32]; // Note: 32 not 128 bits wide constant bits(128) w = V[m, 128]; bits(32) t; for e = 0 to 3 t = SHAmajority(x<63:32>, x<95:64>, x<127:96>); y = y + ROL(x<31:0>, 5) + t + Elem[w, e, 32]; x<63:32> = ROL(x<63:32>, 30); <y, x> = ROL(y : x, 32); V[d, 128] = x;