korb

OR Mask Byte

KORB k1, k2, k3

Bitwise OR of 8-bit masks.

Details

Performs a bitwise OR of two 8-bit AVX-512 opmask registers and stores the result in the destination opmask. This instruction operates on the mask registers (k0–k7) and does not affect EFLAGS. It is part of the AVX-512DQ extension and executes with minimal latency on modern AVX-512 capable processors.

Pseudocode Operation

k1 ← k2 | k3;

Example

KORB k1, k2, k3

Encoding

Binary Layout
EVEX
+0
0F
+4
45
+5
 
Format EVEX
Opcode VEX.L1.66.0F.W0 45 /r
Extension AVX-512DQ

Operands

  • dest
    AVX-512 opmask register (k0-k7)
  • src1
    AVX-512 opmask register (k0-k7)
  • src2
    AVX-512 opmask register (k0-k7)

Reference (Intel® SDM)

Instruction Forms

Opcode Instruction Op/En 64/32-bit Mode CPUID Description
VEX.L1.0F.W0 45 /r KORW k1, k2, k3 V/V RVR AVX512F OR AVX10.1 Bitwise OR 16 bits masks k2 and k3 and place result in k1.
VEX.L1.66.0F.W0 45 /r KORB k1, k2, k3 V/V RVR AVX512DQ OR AVX10.1 Bitwise OR 8 bits masks k2 and k3 and place result in k1.
VEX.L1.0F.W1 45 /r KORQ k1, k2, k3 V/V RVR AVX512BW OR AVX10.1 Bitwise OR 64 bits masks k2 and k3 and place result in k1.
VEX.L1.66.0F.W1 45 /r KORD k1, k2, k3 V/V RVR AVX512BW OR AVX10.1 Bitwise OR 32 bits masks k2 and k3 and place result in k1.

Description

Performs a bitwise OR between the vector mask k2 and the vector mask k3, and writes the result into vector mask k1 (three-operand form).

Operation

KORW
DEST[15:0] := SRC1[15:0] BITWISE OR SRC2[15:0]
DEST[MAX_KL-1:16] := 0

KORB
DEST[7:0] := SRC1[7:0] BITWISE OR SRC2[7:0]
DEST[MAX_KL-1:8] := 0

KORQ
DEST[63:0] := SRC1[63:0] BITWISE OR SRC2[63:0]
DEST[MAX_KL-1:64] := 0

KORD
DEST[31:0] := SRC1[31:0] BITWISE OR SRC2[31:0]
DEST[MAX_KL-1:32] := 0

Intel C/C++ Compiler Intrinsic Equivalent

KORW __mmask16 _mm512_kor(__mmask16 a, __mmask16 b);

Flags Affected

None.

Exceptions

SIMD Floating-Point Exceptions

None.

Other Exceptions

See Table 2-65, “TYPE K20 Exception Definition (VEX-Encoded OpMask Instructions w/o Memory Arg).” KORW/KORB/KORQ/KORD—Bitwise Logical OR Masks Vol. 2A 3-522