VPERM2F128 — Permute Floating-Point Values

Opcode/Instruction Op/En 64/32 bit Mode Support CPUID Feature Flag Description
VEX.256.66.0F3A.W0 06 /r ib VPERM2F128 ymm1, ymm2, ymm3/m256, imm8 RVMI V/V AVX Permute 128-bit floating-point fields 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


Permute 128 bit floating-point-containing fields 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 X1 X0 SRC1 X0, X1, Y0, or Y1 DEST X0, X1, Y0, or Y1
Figure 5-21. VPERM2F128 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.



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]
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]
IF (imm8[3])
DEST[127:0] ← 0
IF (imm8[7])
DEST[MAXVL-1:128] ← 0

Intel C/C++ Compiler Intrinsic Equivalent

VPERM2F128: __m256 _mm256_permute2f128_ps (__m256 a, __m256 b, int control)
VPERM2F128: __m256d _mm256_permute2f128_pd (__m256d a, __m256d b, int control)
VPERM2F128: __m256i _mm256_permute2f128_si256 (__m256i a, __m256i b, int control)

SIMD Floating-Point Exceptions


Other Exceptions

See Exceptions Type 6; additionally

#UD If VEX.L = 0
If VEX.W = 1.