FSCALE (multiple vectors)

Multiply the floating-point elements of the two or four first source vectors by 2.0 to the power of the signed integer values in the corresponding elements of the two or four second source vectors and destructively place the results in the corresponding elements of the two or four first source vectors.

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

Two registers
(FEAT_FP8)

if !IsFeatureImplemented(FEAT_SME2) || !IsFeatureImplemented(FEAT_FP8) then UNDEFINED; if size == '00' then UNDEFINED; constant integer esize = 8 << UInt(size); constant integer dn = UInt(Zdn:'0'); constant integer m = UInt(Zm:'0'); constant integer nreg = 2;

Four registers
(FEAT_FP8)

if !IsFeatureImplemented(FEAT_SME2) || !IsFeatureImplemented(FEAT_FP8) then UNDEFINED; if size == '00' then UNDEFINED; constant integer esize = 8 << UInt(size); constant integer dn = UInt(Zdn:'00'); constant integer m = UInt(Zm:'00'); constant integer nreg = 4;

Assembler Symbols

<Zdn1>	For the two registers variant: is the name of the first scalable vector register of the destination and first source multi-vector group, encoded as "Zdn" times 2.
	For the four registers variant: is the name of the first scalable vector register of the destination and first source multi-vector group, encoded as "Zdn" times 4.

<T>

Is the size specifier, encoded in size:

size	<T>
00	RESERVED
01	H
10	S
11	D

<Zdn4>

Is the name of the fourth scalable vector register of the destination and first source multi-vector group, encoded as "Zdn" times 4 plus 3.

<Zdn2>

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

<Zm1>	For the two registers variant: is the name of the first scalable vector register of the second source multi-vector group, encoded as "Zm" times 2.
	For the four registers variant: is the name of the first scalable vector register of the second source multi-vector group, encoded as "Zm" times 4.

<Zm4>

Is the name of the fourth scalable vector register of the second source multi-vector group, encoded as "Zm" times 4 plus 3.

<Zm2>

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

Operation

CheckStreamingSVEEnabled(); constant integer VL = CurrentVL; constant integer elements = VL DIV esize; array [0..3] of bits(VL) results; for r = 0 to nreg-1 constant bits(VL) operand1 = Z[dn+r, VL]; constant bits(VL) operand2 = Z[m+r, VL]; for e = 0 to elements-1 constant bits(esize) element1 = Elem[operand1, e, esize]; constant integer element2 = SInt(Elem[operand2, e, esize]); Elem[results[r], e, esize] = FPScale(element1, element2, FPCR); for r = 0 to nreg-1 Z[dn+r, VL] = results[r];

Internal version only: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45

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
1	1	0	0	0	0	0	1	size		1	Zm				0	1	0	1	1	0	0	0	1	1	0	0	Zdn				0

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
1	1	0	0	0	0	0	1	size		1	Zm			0	0	1	0	1	1	1	0	0	1	1	0	0	Zdn			0	0