FCVT (widening)

Multi-vector floating-point convert from half-precision to single-precision (in-order)

Convert to single-precision from half-precision, each element of the source vector, and place the results in the double-width destination elements of the destination vectors.

This instruction follows SME2 floating-point numerical behaviors corresponding to instructions that place their results in one or more SVE Z vectors.

This instruction is unpredicated.

ID_AA64SMFR0_EL1.F16F16 indicates whether this instruction is implemented.

SME2
(FEAT_SME_F16F16)

313029282726252423222120191817161514131211109876543210
1100000110100000111000ZnZd0
L

FCVT { <Zd1>.S-<Zd2>.S }, <Zn>.H

if !HaveSME2() || !IsFeatureImplemented(FEAT_SME_F16F16) then UNDEFINED; integer n = UInt(Zn); integer d = UInt(Zd:'0');

Assembler Symbols

<Zd1>

Is the name of the first scalable vector register of the destination multi-vector group, encoded as "Zd" times 2.

<Zd2>

Is the name of the second scalable vector register of the destination multi-vector group, encoded as "Zd" times 2 plus 1.

<Zn>

Is the name of the source scalable vector register, encoded in the "Zn" field.

Operation

CheckStreamingSVEEnabled(); constant integer VL = CurrentVL; constant integer elements = VL DIV 16; bits(VL) operand = Z[n, VL]; bits(2*VL) result; for e = 0 to elements-1 bits(16) element = Elem[operand, e, 16]; bits(32) res = FPConvertSVE(element, FPCR, 32); Elem[result, e, 32] = res; Z[d+0, VL] = result<VL-1:0>; Z[d+1, VL] = result<2*VL-1:VL>;


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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