SMAX (multiple vectors)
Multi-vector signed maximum
Determine the signed maximum of elements of the two or four second source vectors and the corresponding elements of the two or four first source vectors and destructively place the results in the corresponding elements of the two or four first source vectors.
This instruction is unpredicated.
Green
False
True
SM_1_only
It has encodings from 2 classes:
Two registers
and
Four registers
1
1
0
0
0
0
0
1
1
0
1
0
1
1
0
0
0
0
0
0
0
0
SMAX { <Zdn1>.<T>-<Zdn2>.<T> }, { <Zdn1>.<T>-<Zdn2>.<T> }, { <Zm1>.<T>-<Zm2>.<T> }
if !IsFeatureImplemented(FEAT_SME2) then UNDEFINED;
constant integer esize = 8 << UInt(size);
constant integer dn = UInt(Zdn:'0');
constant integer m = UInt(Zm:'0');
constant integer nreg = 2;
constant boolean unsigned = FALSE;
1
1
0
0
0
0
0
1
1
0
0
1
0
1
1
1
0
0
0
0
0
0
0
0
SMAX { <Zdn1>.<T>-<Zdn4>.<T> }, { <Zdn1>.<T>-<Zdn4>.<T> }, { <Zm1>.<T>-<Zm4>.<T> }
if !IsFeatureImplemented(FEAT_SME2) then UNDEFINED;
constant integer esize = 8 << UInt(size);
constant integer dn = UInt(Zdn:'00');
constant integer m = UInt(Zm:'00');
constant integer nreg = 4;
constant boolean unsigned = FALSE;
<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.
<Zdn1>
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,
size
<T>
00
B
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.
<Zm1>
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.
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 integer element1 = Int(Elem[operand1, e, esize], unsigned);
constant integer element2 = Int(Elem[operand2, e, esize], unsigned);
constant integer res = Max(element1, element2);
Elem[results[r], e, esize] = res<esize-1:0>;
for r = 0 to nreg-1
Z[dn+r, VL] = results[r];