Dot product index form with signed and unsigned integers. This instruction performs the dot product of the four signed 8-bit integer values in each 32-bit element of the first source register with the four unsigned 8-bit integer values in an indexed 32-bit element of the second source register, accumulating the result into the corresponding 32-bit element of the destination vector.
From Armv8.2 to Armv8.5, this is an optional instruction. From Armv8.6 it is mandatory for implementations that include Advanced SIMD to support it. ID_AA64ISAR1_EL1.I8MM indicates whether this instruction is supported.
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 0 | Q | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 0 | L | M | Rm | 1 | 1 | 1 | 1 | H | 0 | Rn | Rd | |||||||||||
| US | |||||||||||||||||||||||||||||||
if !HaveInt8MatMulExt() then UNDEFINED; boolean op1_unsigned = (US == '1'); boolean op2_unsigned = (US == '0'); integer n = UInt(Rn); integer m = UInt(M:Rm); integer d = UInt(Rd); integer i = UInt(H:L); integer datasize = if Q == '1' then 128 else 64; integer elements = datasize DIV 32;
| <Vd> |
Is the name of the SIMD&FP third source and destination register, encoded in the "Rd" field. |
| <Ta> |
Is an arrangement specifier,
encoded in
|
| <Vn> |
Is the name of the first SIMD&FP source register, encoded in the "Rn" field. |
| <Tb> |
Is an arrangement specifier,
encoded in
|
| <Vm> |
Is the name of the second SIMD&FP source register, encoded in the "M:Rm" fields. |
| <index> |
Is the immediate index of a quadtuplet of four 8-bit elements in the range 0 to 3, encoded in the "H:L" fields. |
CheckFPAdvSIMDEnabled64(); bits(datasize) operand1 = V[n]; bits(128) operand2 = V[m]; bits(datasize) operand3 = V[d]; bits(datasize) result; for e = 0 to elements-1 bits(32) res = Elem[operand3, e, 32]; for b = 0 to 3 integer element1 = Int(Elem[operand1, 4 * e + b, 8], op1_unsigned); integer element2 = Int(Elem[operand2, 4 * i + b, 8], op2_unsigned); res = res + element1 * element2; Elem[result, e, 32] = res; V[d] = result;
Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41
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