While decrementing signed scalar greater than scalar
Generate a predicate that starting from the highest numbered element is true while the decrementing value of the first, signed scalar operand is greater than the second scalar operand and false thereafter down to the lowest numbered element.
The full width of the scalar operands is significant for the purposes of comparison, and the full width first operand is decremented by one for each destination predicate element, irrespective of the predicate result element size. The first general-purpose source register is not itself updated.
The predicate result is placed in the predicate destination register. Sets the First (N), None (Z), !Last (C) condition flags based on the predicate result, and the V flag to zero.
| 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 | Rm | 0 | 0 | 0 | sf | 0 | 0 | Rn | 1 | Pd | ||||||||||||
| U | lt | eq | |||||||||||||||||||||||||||||
if !HaveSVE2() && !HaveSME() then UNDEFINED; integer esize = 8 << UInt(size); integer rsize = 32 << UInt(sf); integer n = UInt(Rn); integer m = UInt(Rm); integer d = UInt(Pd); boolean unsigned = FALSE; SVECmp op = Cmp_GT;
| <Pd> |
Is the name of the destination scalable predicate register, encoded in the "Pd" field. |
| <T> |
Is the size specifier,
encoded in
|
| <R> |
Is a width specifier,
encoded in
|
| <n> |
Is the number [0-30] of the source general-purpose register or the name ZR (31), encoded in the "Rn" field. |
| <m> |
Is the number [0-30] of the source general-purpose register or the name ZR (31), encoded in the "Rm" field. |
CheckSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = Ones(PL); bits(rsize) operand1 = X[n]; bits(rsize) operand2 = X[m]; bits(PL) result; boolean last = TRUE; for e = elements-1 downto 0 boolean cond; case op of when Cmp_GT cond = (Int(operand1, unsigned) > Int(operand2, unsigned)); when Cmp_GE cond = (Int(operand1, unsigned) >= Int(operand2, unsigned)); last = last && cond; ElemP[result, e, esize] = if last then '1' else '0'; operand1 = operand1 - 1; PSTATE.<N,Z,C,V> = PredTest(mask, result, esize); P[d] = result;
If FEAT_SVE2 is enabled or FEAT_SME is enabled, then when PSTATE.DIT is 1:
Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41
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