LSLR
Reversed logical shift left by vector (predicated)
Reversed shift left active elements of the second source vector by corresponding elements of the first source vector and destructively place the results in the corresponding elements of the first source vector. The shift amount operand is a vector of unsigned elements in which all bits are significant, and not used modulo the element size. Inactive elements in the destination vector register remain unmodified.
Green
True
True
True
True
0
0
0
0
0
1
0
0
0
1
0
1
1
1
1
0
0
LSLR <Zdn>.<T>, <Pg>/M, <Zdn>.<T>, <Zm>.<T>
if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then UNDEFINED;
constant integer esize = 8 << UInt(size);
constant integer g = UInt(Pg);
constant integer dn = UInt(Zdn);
constant integer m = UInt(Zm);
<Zdn>
Is the name of the first source and destination scalable vector register, encoded in the "Zdn" field.
<T>
Is the size specifier,
size
<T>
00
B
01
H
10
S
11
D
<Pg>
Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field.
<Zm>
Is the name of the second source scalable vector register, encoded in the "Zm" field.
CheckSVEEnabled();
constant integer VL = CurrentVL;
constant integer PL = VL DIV 8;
constant integer elements = VL DIV esize;
constant bits(PL) mask = P[g, PL];
constant bits(VL) operand1 = Z[dn, VL];
constant bits(VL) operand2 = if AnyActiveElement(mask, esize) then Z[m, VL] else Zeros(VL);
bits(VL) result;
for e = 0 to elements-1
if ActivePredicateElement(mask, e, esize) then
constant bits(esize) element1 = Elem[operand1, e, esize];
constant bits(esize) element2 = Elem[operand2, e, esize];
constant integer shift = Min(UInt(element1), esize);
Elem[result, e, esize] = LSL(element2, shift);
else
Elem[result, e, esize] = Elem[operand1, e, esize];
Z[dn, VL] = result;