NEG (vector)
Negate (vector)
This instruction reads each vector element from the source SIMD&FP register,
negates each value, puts the result into a vector, and writes the
vector to the destination SIMD&FP register.
Depending on the settings in the CPACR_EL1,
CPTR_EL2, and CPTR_EL3 registers,
and the current Security state and Exception level,
an attempt to execute the instruction might be trapped.
If PSTATE.DIT is 1:
The execution time of this instruction is independent of:
The values of the data supplied in any of its registers.
The values of the NZCV flags.
The response of this instruction to asynchronous exceptions does not vary based on:
The values of the data supplied in any of its registers.
The values of the NZCV flags.
It has encodings from 2 classes:
Scalar
and
Vector
0
1
1
1
1
1
1
0
1
1
1
0
0
0
0
0
1
0
1
1
1
0
NEG D<d>, D<n>
if size != '11' then UNDEFINED;
constant integer d = UInt(Rd);
constant integer n = UInt(Rn);
constant integer esize = 8 << UInt(size);
constant integer datasize = esize;
constant integer elements = 1;
0
1
0
1
1
1
0
1
0
0
0
0
0
1
0
1
1
1
0
NEG <Vd>.<T>, <Vn>.<T>
if size:Q == '110' then UNDEFINED;
constant integer d = UInt(Rd);
constant integer n = UInt(Rn);
constant integer esize = 8 << UInt(size);
constant integer datasize = 64 << UInt(Q);
constant integer elements = datasize DIV esize;
<d>
Is the number of the SIMD&FP destination register, encoded in the "Rd" field.
<n>
Is the number of the SIMD&FP source register, encoded in the "Rn" field.
<Vd>
Is the name of the SIMD&FP destination register, encoded in the "Rd" field.
<T>
Is an arrangement specifier,
size
Q
<T>
00
0
8B
00
1
16B
01
0
4H
01
1
8H
10
0
2S
10
1
4S
11
0
RESERVED
11
1
2D
<Vn>
Is the name of the SIMD&FP source register, encoded in the "Rn" field.
CheckFPAdvSIMDEnabled64();
constant bits(datasize) operand = V[n, datasize];
bits(datasize) result;
integer element;
for e = 0 to elements-1
element = SInt(Elem[operand, e, esize]);
element = -element;
Elem[result, e, esize] = element<esize-1:0>;
V[d, datasize] = result;