UHSUB Unsigned halving subtract This instruction subtracts the vector elements in the second source SIMD&FP register from the corresponding vector elements in the first source SIMD&FP register, shifts each result right one bit, places each result into a vector, and writes the vector to the destination SIMD&FP register. Depending on the settings in the CPACR_EL1, CPTR_EL2, and CPTR_EL3 registers, and the current Security state and Exception level, an attempt to execute the instruction might be trapped. 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 0 1 0 0 1 0 0 1 UHSUB <Vd>.<T>, <Vn>.<T>, <Vm>.<T> constant integer d = UInt(Rd); constant integer n = UInt(Rn); constant integer m = UInt(Rm); if size == '11' then UNDEFINED; constant integer esize = 8 << UInt(size); constant integer datasize = 64 << UInt(Q); constant integer elements = datasize DIV esize; <Vd> Is the name of the SIMD&FP destination register, encoded in the "Rd" field. <T> Is an arrangement specifier, size Q <T> 00 0 8B 00 1 16B 01 0 4H 01 1 8H 10 0 2S 10 1 4S 11 x RESERVED <Vn> Is the name of the first SIMD&FP source register, encoded in the "Rn" field. <Vm> Is the name of the second SIMD&FP source register, encoded in the "Rm" field. CheckFPAdvSIMDEnabled64(); constant bits(datasize) operand1 = V[n, datasize]; constant bits(datasize) operand2 = V[m, datasize]; bits(datasize) result; integer element1; integer element2; integer diff; for e = 0 to elements-1 element1 = UInt(Elem[operand1, e, esize]); element2 = UInt(Elem[operand2, e, esize]); diff = (element1 - element2) >> 1; Elem[result, e, esize] = diff<esize-1:0>; V[d, datasize] = result;