# KNOTW/KNOTB/KNOTQ/KNOTD — NOT Mask Register

Opcode/Instruction | Op/En | 64/32 bit Mode Support | CPUID Feature Flag | Description
--- | --- | --- | --- | ---
VEX.L0.0F.W0 44 /r KNOTW k1, k2 | RR | V/V | AVX512F | Bitwise NOT of 16 bits mask k2.
VEX.L0.66.0F.W0 44 /r KNOTB k1, k2 | RR | V/V | AVX512DQ | Bitwise NOT of 8 bits mask k2.
VEX.L0.0F.W1 44 /r KNOTQ k1, k2 | RR | V/V | AVX512BW | Bitwise NOT of 64 bits mask k2.
VEX.L0.66.0F.W1 44 /r KNOTD k1, k2 | RR | V/V | AVX512BW | Bitwise NOT of 32 bits mask k2.

## Instruction Operand Encoding ¶

Op/En | Operand 1 | Operand 2
--- | --- | ---
RR | ModRM:reg (w) | ModRM:r/m (r, ModRM:[7:6] must be 11b)

## Description ¶

Performs a bitwise NOT of vector mask k2 and writes the result into vector mask k1.

## Operation ¶

### KNOTW ¶

    DEST[15:0] := BITWISE NOT SRC[15:0]
    DEST[MAX_KL-1:16] := 0

### KNOTB ¶

    DEST[7:0] := BITWISE NOT SRC[7:0]
    DEST[MAX_KL-1:8] := 0

### KNOTQ ¶

    DEST[63:0] := BITWISE NOT SRC[63:0]
    DEST[MAX_KL-1:64] := 0

### KNOTD ¶

    DEST[31:0] := BITWISE NOT SRC[31:0]
    DEST[MAX_KL-1:32] := 0

## Intel C/C++ Compiler Intrinsic Equivalent ¶

    KNOTW __mmask16 _mm512_knot(__mmask16 a);

## Flags Affected ¶

None.

## SIMD Floating-Point Exceptions ¶

None.

## Other Exceptions ¶

See Table 2-63, “TYPE K20 Exception Definition (VEX-Encoded OpMask Instructions w/o Memory Arg).”