FCVTLT

Floating-point up convert long (top, predicated)

Convert odd-numbered floating-point elements from the source vector to the next higher precision, and place the results in the active overlapping double-width elements of the destination vector. Inactive elements in the destination vector register remain unmodified.

It has encodings from 2 classes: Half-precision to single-precision and Single-precision to double-precision

Half-precision to single-precision

313029282726252423222120191817161514131211109876543210
0110010010001001101PgZnZd

FCVTLT <Zd>.S, <Pg>/M, <Zn>.H

if !HaveSVE2() && !HaveSME() then UNDEFINED; constant integer esize = 32; integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Zd);

Single-precision to double-precision

313029282726252423222120191817161514131211109876543210
0110010011001011101PgZnZd

FCVTLT <Zd>.D, <Pg>/M, <Zn>.S

if !HaveSVE2() && !HaveSME() then UNDEFINED; constant integer esize = 64; integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Zd);

Assembler Symbols

<Zd>

Is the name of the destination scalable vector register, encoded in the "Zd" field.

<Pg>

Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field.

<Zn>

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

Operation

CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; bits(PL) mask = P[g, PL]; bits(VL) operand = if AnyActiveElement(mask, esize) then Z[n, VL] else Zeros(VL); bits(VL) result = Z[d, VL]; for e = 0 to elements-1 if ActivePredicateElement(mask, e, esize) then bits(esize DIV 2) element = Elem[operand, 2*e + 1, esize DIV 2]; Elem[result, e, esize] = FPConvertSVE(element, FPCR, esize); Z[d, VL] = result;


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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