8-bit floating-point convert to BFloat16 (top)
Convert each odd-numbered 8-bit floating-point element of the source vector to BFloat16 while downscaling the value, and place the results in the overlapping 16-bit elements of the destination vector. BF1CVTLT scales the values by 2-UInt(FPMR.LSCALE[5:0]). BF2CVTLT scales the values by 2-UInt(FPMR.LSCALE2[5:0]).
The 8-bit floating-point encoding format for BF1CVTLT is selected by FPMR.F8S1. The 8-bit floating-point encoding format for BF2CVTLT is selected by FPMR.F8S2.
This instruction is unpredicated.
It has encodings from 2 classes: BF1CVTLT and BF2CVTLT
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| 0 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 1 | 1 | 1 | 0 | Zn | Zd | ||||||||
| L | |||||||||||||||||||||||||||||||
if ((!IsFeatureImplemented(FEAT_SVE2) && !IsFeatureImplemented(FEAT_SME2)) || !IsFeatureImplemented(FEAT_FP8)) then UNDEFINED; constant integer esize = 16; constant integer n = UInt(Zn); constant integer d = UInt(Zd); constant boolean issrc2 = FALSE;
| 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 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | Zn | Zd | ||||||||
| L | |||||||||||||||||||||||||||||||
if ((!IsFeatureImplemented(FEAT_SVE2) && !IsFeatureImplemented(FEAT_SME2)) || !IsFeatureImplemented(FEAT_FP8)) then UNDEFINED; constant integer esize = 16; constant integer n = UInt(Zn); constant integer d = UInt(Zd); constant boolean issrc2 = TRUE;
| <Zd> |
Is the name of the destination scalable vector register, encoded in the "Zd" field. |
| <Zn> |
Is the name of the source scalable vector register, encoded in the "Zn" field. |
CheckFPMREnabled(); CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer elements = VL DIV esize; constant bits(VL) operand = Z[n, VL]; bits(VL) result; for e = 0 to elements-1 constant bits(esize DIV 2) element = Elem[operand, 2*e + 1, esize DIV 2]; Elem[result, e, esize] = FP8ConvertBF(element, issrc2, FPCR, FPMR); Z[d, VL] = result;
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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