UMAXP

Unsigned Maximum Pairwise. This instruction creates a vector by concatenating the vector elements of the first source SIMD&FP register after the vector elements of the second source SIMD&FP register, reads each pair of adjacent vector elements in the two source SIMD&FP registers, writes the largest of each pair of unsigned integer values 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.

313029282726252423222120191817161514131211109876543210
0Q101110size1Rm101001RnRd
Uo1

UMAXP <Vd>.<T>, <Vn>.<T>, <Vm>.<T>

integer d = UInt(Rd); integer n = UInt(Rn); integer m = UInt(Rm); if size == '11' then UNDEFINED; constant integer esize = 8 << UInt(size); constant integer datasize = 64 << UInt(Q); integer elements = datasize DIV esize; boolean unsigned = (U == '1'); boolean minimum = (o1 == '1');

Assembler Symbols

<Vd>

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

<T>

Is an arrangement specifier, encoded in size:Q:

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.

Operation

CheckFPAdvSIMDEnabled64(); bits(datasize) operand1 = V[n, datasize]; bits(datasize) operand2 = V[m, datasize]; bits(datasize) result; bits(2*datasize) concat = operand2:operand1; integer element1; integer element2; integer maxmin; for e = 0 to elements-1 element1 = Int(Elem[concat, 2*e, esize], unsigned); element2 = Int(Elem[concat, (2*e)+1, esize], unsigned); maxmin = if minimum then Min(element1, element2) else Max(element1, element2); Elem[result, e, esize] = maxmin<esize-1:0>; V[d, datasize] = result;

Operational information

If PSTATE.DIT is 1:


Internal version only: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46

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