Half-precision floating-point dot product
This instruction computes the fused sum-of-products of a pair of half-precision floating-point values held in each 32-bit element of the first source and second source vectors, without intermediate rounding, and then destructively adds the single-precision sum-of-products to the corresponding single-precision element of the destination vector.
This instruction is unpredicated.
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 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | Zm | 1 | 0 | 0 | 0 | 0 | 0 | Zn | Zda |
if !IsFeatureImplemented(FEAT_SME2) && !IsFeatureImplemented(FEAT_SVE2p1) then UNDEFINED; constant integer n = UInt(Zn); constant integer m = UInt(Zm); constant integer da = UInt(Zda);
<Zda> |
Is the name of the third source and destination scalable vector register, encoded in the "Zda" field. |
<Zn> |
Is the name of the first source scalable vector register, encoded in the "Zn" field. |
<Zm> |
Is the name of the second source scalable vector register, encoded in the "Zm" field. |
CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV 32; constant bits(VL) operand1 = Z[n, VL]; constant bits(VL) operand2 = Z[m, VL]; constant bits(VL) operand3 = Z[da, VL]; bits(VL) result; for e = 0 to elements-1 constant bits(16) elt1_a = Elem[operand1, 2 * e + 0, 16]; constant bits(16) elt1_b = Elem[operand1, 2 * e + 1, 16]; constant bits(16) elt2_a = Elem[operand2, 2 * e + 0, 16]; constant bits(16) elt2_b = Elem[operand2, 2 * e + 1, 16]; bits(32) sum = Elem[operand3, e, 32]; sum = FPDotAdd(sum, elt1_a, elt1_b, elt2_a, elt2_b, FPCR); Elem[result, e, 32] = sum; Z[da, VL] = result;
This instruction might be immediately preceded in program order by a MOVPRFX instruction. The MOVPRFX must conform to all of the following requirements, otherwise the behavior of the MOVPRFX and this instruction is constrained unpredictable:
Internal version only: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45
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