Signed saturating decrement vector by active predicate element count.
Counts the number of active elements in the source predicate and then uses the result to decrement all destination vector elements. The results are saturated to the element signed integer range.
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 | 0 | 1 | 0 | 0 | 1 | 0 | 1 | size | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | Pg | Zdn |
if !HaveSVE() then UNDEFINED; if size == '00' then UNDEFINED; integer esize = 8 << UInt(size); integer g = UInt(Pg); integer dn = UInt(Zdn); boolean unsigned = FALSE;
<Zdn> |
Is the name of the source and destination scalable vector register, encoded in the "Zdn" field. |
<T> |
Is the size specifier,
encoded in
size:
|
<Pg> |
Is the name of the governing scalable predicate register, encoded in the "Pg" field. |
CheckSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = P[g]; bits(VL) operand = Z[dn]; bits(VL) result; integer count = 0; for e = 0 to elements-1 if ElemP[mask, e, esize] == '1' then count = count + 1; for e = 0 to elements-1 integer element = Int(Elem[operand, e, esize], unsigned); (Elem[result, e, esize], -) = SatQ(element - count, esize, unsigned); Z[dn] = result;
Internal version only: isa v30.41, AdvSIMD v27.08, pseudocode r8p5_00bet2_rc5, sve v8.5-00bet10_rc5 ; Build timestamp: 2019-03-28T07:14
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