VPERM2I128 - Permute Integer Values

Opcode/ Instruction

Op/ En

64/32 -bit Mode

CPUID Feature Flag

Description

VEX.256.66.0F3A.W0 46 /r ib VPERM2I128 ymm1, ymm2, ymm3/m256, imm8

RVMI

V/V

AVX2

Permute 128-bit integer data in ymm2 and ymm3/mem using controls from imm8 and store result in ymm1.

Instruction Operand Encoding

Op/En

Operand 1

Operand 2

Operand 3

Operand 4

RVMI

ModRM:reg (w)

VEX.vvvv (r)

ModRM:r/m (r)

imm8

Description

Permute 128 bit integer data from the first source operand (second operand) and second source operand (third operand) using bits in the 8-bit immediate and store results in the destination operand (first operand). The first source operand is a YMM register, the second source operand is a YMM register or a 256-bit memory location, and the destination operand is a YMM register.

Y1

Y0

SRC2

SRC1

DEST

X0, X1, Y0, or Y1

X0, X1, Y0, or Y1

Figure 5-22. VPERM2I128 Operation

Imm8[1:0] select the source for the first destination 128-bit field, imm8[5:4] select the source for the second destination field. If imm8[3] is set, the low 128-bit field is zeroed. If imm8[7] is set, the high 128-bit field is zeroed.

VEX.L must be 1, otherwise the instruction will #UD.

Operation

VPERM2I128 

CASE IMM8[1:0] of 
0: DEST[127:0] := SRC1[127:0]
1: DEST[127:0] := SRC1[255:128]
2: DEST[127:0] := SRC2[127:0]
3: DEST[127:0] := SRC2[255:128]
ESAC
CASE IMM8[5:4] of 
0: DEST[255:128] := SRC1[127:0]
1: DEST[255:128] := SRC1[255:128]
2: DEST[255:128] := SRC2[127:0]
3: DEST[255:128] := SRC2[255:128]
ESAC
IF (imm8[3])
DEST[127:0] := 0
FI
IF (imm8[7])
DEST[255:128] := 0
FI

Intel C/C++ Compiler Intrinsic Equivalent 

VPERM2I128: __m256i _mm256_permute2x128_si256 (__m256i a, __m256i b, int control)

SIMD Floating-Point Exceptions

None

Other Exceptions

See Table 2-23, "Type 6 Class Exception Conditions."

Additionally:

#UD

If VEX.L = 0, If VEX.W = 1.