vextracti128

Extract Integer 128-bit

VEXTRACTI128 xmm1/m128, ymm2, imm8

Extracts 128-bits of integer data from YMM.

Details

Extracts a 128-bit integer value from the source YMM register and stores it in the destination XMM register or memory location. The specific 128-bit lane extracted is determined by the immediate operand (imm8[0]=0 for lower 128 bits, imm8[0]=1 for upper 128 bits). No flags are affected. This is a VEX-encoded AVX2 instruction that complements VINSERTI128 for manipulating 256-bit vectors.

Pseudocode Operation

if (imm8[0] == 0) {
  dest ← src1[127:0];
} else {
  dest ← src1[255:128];
}

Example

VEXTRACTI128 xmm1/m128, ymm2, 3

Encoding

Binary Layout
VEX
+0
opcode
+3
ModRM
+4
 
Format VEX
Opcode VEX.256.66.0F3A.W0 39 /r ib
Extension AVX2

Operands

  • dest
    128-bit XMM SIMD register or Memory operand
  • src1
    256-bit YMM AVX register
  • src2
    8-bit signed immediate

Reference (Intel® SDM)

Instruction Forms

Opcode Instruction Op/En 64/32-bit Mode CPUID Description
VEX.256.66.0F3A.W0 39 /r ib VEXTRACTI128 xmm1/m128, ymm2, imm8 A V/V AVX2 Extract 128 bits of integer data from ymm2 and store results in xmm1/m128.
EVEX.256.66.0F3A.W0 39 /r ib VEXTRACTI32X4 xmm1/m128 {k1}{z}, ymm2, imm8 C V/V (AVX512VL AND AVX512F) OR AVX10.1 Extract 128 bits of double-word integer values from ymm2 and store results in xmm1/m128 subject to writemask k1.
EVEX.256.66.0F3A.W1 39 /r ib VEXTRACTI64X2 xmm1/m128 {k1}{z}, ymm2, imm8 B V/V (AVX512VL AND AVX512DQ) OR AVX10.1 Extract 128 bits of quad-word integer values from ymm2 and store results in xmm1/m128 subject to writemask k1.
EVEX.512.66.0F3A.W1 39 /r ib VEXTRACTI64X2 xmm1/m128 {k1}{z}, zmm2, imm8 B V/V AVX512DQ OR AVX10.1 Extract 128 bits of quad-word integer values from zmm2 and store results in xmm1/m128 subject to writemask k1.
EVEX.512.66.0F3A.W0 3B /r ib VEXTRACTI32X8 ymm1/m256 {k1}{z}, zmm2, imm8 D V/V AVX512DQ OR AVX10.1 Extract 256 bits of double-word integer values from zmm2 and store results in ymm1/m256 subject to writemask k1.

Instruction Operand Encoding

Op/En Tuple Type Operand 1 Operand 2 Operand 3 Operand 4
A N/A ModRM:r/m (w) ModRM:reg (r) imm8 N/A
B Tuple2 ModRM:r/m (w) ModRM:reg (r) imm8 N/A
C Tuple4 ModRM:r/m (w) ModRM:reg (r) imm8 N/A
D Tuple8 ModRM:r/m (w) ModRM:reg (r) imm8 N/A

Description

VEXTRACTI128/VEXTRACTI32x4 and VEXTRACTI64x2 extract 128-bits of doubleword integer values from the source operand (the second operand) and store to the low 128-bit of the destination operand (the first operand). The 128-bit data extraction occurs at an 128-bit granular offset specified by imm8[0] (256-bit) or imm8[1:0] as the multiply factor. The destination may be either a vector register or an 128-bit memory location. VEXTRACTI32x4: The low 128-bit of the destination operand is updated at 32-bit granularity according to the writemask. VEXTRACTI64x2: The low 128-bit of the destination operand is updated at 64-bit granularity according to the writemask. VEXTRACTI32x8 and VEXTRACTI64x4 extract 256-bits of quadword integer values from the source operand (the second operand) and store to the low 256-bit of the destination operand (the first operand). The 256-bit data extraction occurs at an 256-bit granular offset specified by imm8[0] (256-bit) or imm8[0] as the multiply factor The destination may be either a vector register or a 256-bit memory location. VEXTRACTI32x8: The low 256-bit of the destination operand is updated at 32-bit granularity according to the writemask. VEXTRACTI128/VEXTRACTI32x4/VEXTRACTI64x2/VEXTRACTI32x8/VEXTRACTI64x4—Extract Packed Integer Values Vol. 2C 5-174 VEXTRACTI64x4: The low 256-bit of the destination operand is updated at 64-bit granularity according to the writemask. VEX.vvvv and EVEX.vvvv are reserved and must be 1111b otherwise instructions will #UD. The high 7 bits (6 bits in EVEX.512) of the immediate are ignored. If VEXTRACTI128 is encoded with VEX.L= 0, an attempt to execute the instruction encoded with VEX.L= 0 will cause an #UD exception.

Operation

VEXTRACTI32x4 (EVEX encoded versions) when destination is a register
VL = 256, 512
IF VL = 256
CASE (imm8[0]) OF
0: TMP_DEST[127:0] := SRC1[127:0]
1: TMP_DEST[127:0] := SRC1[255:128]
ESAC.
FI;
IF VL = 512
CASE (imm8[1:0]) OF
00: TMP_DEST[127:0] := SRC1[127:0]
01: TMP_DEST[127:0] := SRC1[255:128]
10: TMP_DEST[127:0] := SRC1[383:256]
11: TMP_DEST[127:0] := SRC1[511:384]
ESAC.
FI;
FOR j := 0 TO 3
i := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+31:i] := TMP_DEST[i+31:i]
ELSE
IF *merging-masking*                                 ; merging-masking
THEN *DEST[i+31:i] remains unchanged*
ELSE *zeroing-masking*                            ; zeroing-masking
DEST[i+31:i] := 0
FI
FI;
ENDFOR
DEST[MAXVL-1:128] := 0

VEXTRACTI32x4 (EVEX encoded versions) when destination is memory
VL = 256, 512
IF VL = 256
CASE (imm8[0]) OF
0: TMP_DEST[127:0] := SRC1[127:0]
1: TMP_DEST[127:0] := SRC1[255:128]
ESAC.
FI;
IF VL = 512
CASE (imm8[1:0]) OF
00: TMP_DEST[127:0] := SRC1[127:0]
01: TMP_DEST[127:0] := SRC1[255:128]
10: TMP_DEST[127:0] := SRC1[383:256]
11: TMP_DEST[127:0] := SRC1[511:384]
ESAC.


VEXTRACTI128/VEXTRACTI32x4/VEXTRACTI64x2/VEXTRACTI32x8/VEXTRACTI64x4—Extract Packed Integer Values                   Vol. 2C 5-175
FI;

FOR j := 0 TO 3
i := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+31:i] := TMP_DEST[i+31:i]
ELSE *DEST[i+31:i] remains unchanged*               ; merging-masking
FI;
ENDFOR

VEXTRACTI64x2 (EVEX encoded versions) when destination is a register
VL = 256, 512
IF VL = 256
CASE (imm8[0]) OF
0: TMP_DEST[127:0] := SRC1[127:0]
1: TMP_DEST[127:0] := SRC1[255:128]
ESAC.
FI;
IF VL = 512
CASE (imm8[1:0]) OF
00: TMP_DEST[127:0] := SRC1[127:0]
01: TMP_DEST[127:0] := SRC1[255:128]
10: TMP_DEST[127:0] := SRC1[383:256]
11: TMP_DEST[127:0] := SRC1[511:384]
ESAC.
FI;

FOR j := 0 TO 1
i := j * 64
IF k1[j] OR *no writemask*
THEN DEST[i+63:i] := TMP_DEST[i+63:i]
ELSE
IF *merging-masking*                                 ; merging-masking
THEN *DEST[i+63:i] remains unchanged*
ELSE *zeroing-masking*                            ; zeroing-masking
DEST[i+63:i] := 0
FI
FI;
ENDFOR
DEST[MAXVL-1:128] := 0

VEXTRACTI64x2 (EVEX encoded versions) when destination is memory
VL = 256, 512
IF VL = 256
CASE (imm8[0]) OF
0: TMP_DEST[127:0] := SRC1[127:0]
1: TMP_DEST[127:0] := SRC1[255:128]
ESAC.
FI;
IF VL = 512
CASE (imm8[1:0]) OF
00: TMP_DEST[127:0] := SRC1[127:0]
01: TMP_DEST[127:0] := SRC1[255:128]
10: TMP_DEST[127:0] := SRC1[383:256]


VEXTRACTI128/VEXTRACTI32x4/VEXTRACTI64x2/VEXTRACTI32x8/VEXTRACTI64x4—Extract Packed Integer Values                   Vol. 2C 5-176
11: TMP_DEST[127:0] := SRC1[511:384]
ESAC.
FI;

FOR j := 0 TO 1
i := j * 64
IF k1[j] OR *no writemask*
THEN DEST[i+63:i] := TMP_DEST[i+63:i]
ELSE *DEST[i+63:i] remains unchanged*               ; merging-masking
FI;
ENDFOR

VEXTRACTI32x8 (EVEX.U1.512 encoded version) when destination is a register
VL = 512
CASE (imm8[0]) OF
0: TMP_DEST[255:0] := SRC1[255:0]
1: TMP_DEST[255:0] := SRC1[511:256]
ESAC.

FOR j := 0 TO 7
i := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+31:i] := TMP_DEST[i+31:i]
ELSE
IF *merging-masking*                                 ; merging-masking
THEN *DEST[i+31:i] remains unchanged*
ELSE *zeroing-masking*                            ; zeroing-masking
DEST[i+31:i] := 0
FI
FI;
ENDFOR
DEST[MAXVL-1:256] := 0

VEXTRACTI32x8 (EVEX.U1.512 encoded version) when destination is memory
CASE (imm8[0]) OF
0: TMP_DEST[255:0] := SRC1[255:0]
1: TMP_DEST[255:0] := SRC1[511:256]
ESAC.

FOR j := 0 TO 7
i := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+31:i] := TMP_DEST[i+31:i]
ELSE *DEST[i+31:i] remains unchanged*               ; merging-masking
FI;
ENDFOR





VEXTRACTI128/VEXTRACTI32x4/VEXTRACTI64x2/VEXTRACTI32x8/VEXTRACTI64x4—Extract Packed Integer Values                   Vol. 2C 5-177
VEXTRACTI64x4 (EVEX.512 encoded version) when destination is a register
VL = 512
CASE (imm8[0]) OF
0: TMP_DEST[255:0] := SRC1[255:0]
1: TMP_DEST[255:0] := SRC1[511:256]
ESAC.

FOR j := 0 TO 3
i := j * 64
IF k1[j] OR *no writemask*
THEN DEST[i+63:i] := TMP_DEST[i+63:i]
ELSE
IF *merging-masking*                                 ; merging-masking
THEN *DEST[i+63:i] remains unchanged*
ELSE *zeroing-masking*                            ; zeroing-masking
DEST[i+63:i] := 0
FI
FI;
ENDFOR
DEST[MAXVL-1:256] := 0

VEXTRACTI64x4 (EVEX.512 encoded version) when destination is memory
CASE (imm8[0]) OF
0: TMP_DEST[255:0] := SRC1[255:0]
1: TMP_DEST[255:0] := SRC1[511:256]
ESAC.
FOR j := 0 TO 3
i := j * 64
IF k1[j] OR *no writemask*
THEN DEST[i+63:i] := TMP_DEST[i+63:i]
ELSE *DEST[i+63:i] remains unchanged*               ; merging-masking
FI;
ENDFOR

VEXTRACTI128 (memory destination form)
CASE (imm8[0]) OF
0: DEST[127:0] := SRC1[127:0]
1: DEST[127:0] := SRC1[255:128]
ESAC.

VEXTRACTI128 (register destination form)
CASE (imm8[0]) OF
0: DEST[127:0] := SRC1[127:0]
1: DEST[127:0] := SRC1[255:128]
ESAC.
DEST[MAXVL-1:128] := 0





VEXTRACTI128/VEXTRACTI32x4/VEXTRACTI64x2/VEXTRACTI32x8/VEXTRACTI64x4—Extract Packed Integer Values                   Vol. 2C 5-178

Intel C/C++ Compiler Intrinsic Equivalent

VEXTRACTI32x4 __m128i _mm512_extracti32x4_epi32(__m512i a, const int nidx);
VEXTRACTI32x4 __m128i _mm512_mask_extracti32x4_epi32(__m128i s, __mmask8 k, __m512i a, const int nidx);
VEXTRACTI32x4 __m128i _mm512_maskz_extracti32x4_epi32( __mmask8 k, __m512i a, const int nidx);
VEXTRACTI32x4 __m128i _mm256_extracti32x4_epi32(__m256i a, const int nidx);
VEXTRACTI32x4 __m128i _mm256_mask_extracti32x4_epi32(__m128i s, __mmask8 k, __m256i a, const int nidx);
VEXTRACTI32x4 __m128i _mm256_maskz_extracti32x4_epi32( __mmask8 k, __m256i a, const int nidx);
VEXTRACTI32x8 __m256i _mm512_extracti32x8_epi32(__m512i a, const int nidx);
VEXTRACTI32x8 __m256i _mm512_mask_extracti32x8_epi32(__m256i s, __mmask8 k, __m512i a, const int nidx);
VEXTRACTI32x8 __m256i _mm512_maskz_extracti32x8_epi32( __mmask8 k, __m512i a, const int nidx);
VEXTRACTI64x2 __m128i _mm512_extracti64x2_epi64(__m512i a, const int nidx);
VEXTRACTI64x2 __m128i _mm512_mask_extracti64x2_epi64(__m128i s, __mmask8 k, __m512i a, const int nidx);
VEXTRACTI64x2 __m128i _mm512_maskz_extracti64x2_epi64( __mmask8 k, __m512i a, const int nidx);
VEXTRACTI64x2 __m128i _mm256_extracti64x2_epi64(__m256i a, const int nidx);
VEXTRACTI64x2 __m128i _mm256_mask_extracti64x2_epi64(__m128i s, __mmask8 k, __m256i a, const int nidx);
VEXTRACTI64x2 __m128i _mm256_maskz_extracti64x2_epi64( __mmask8 k, __m256i a, const int nidx);
VEXTRACTI64x4 __m256i _mm512_extracti64x4_epi64(__m512i a, const int nidx);
VEXTRACTI64x4 __m256i _mm512_mask_extracti64x4_epi64(__m256i s, __mmask8 k, __m512i a, const int nidx);
VEXTRACTI64x4 __m256i _mm512_maskz_extracti64x4_epi64( __mmask8 k, __m512i a, const int nidx);
VEXTRACTI128 __m128i _mm256_extracti128_si256(__m256i a, int offset);

Exceptions

SIMD Floating-Point Exceptions

None

Other Exceptions

VEX-encoded instructions, see Table 2-23, “Type 6 Class Exception Conditions.” EVEX-encoded instructions, see Table 2-56, “Type E6NF Class Exception Conditions.” Additionally: #UD IF VEX.L = 0. #UD If VEX.vvvv != 1111B or EVEX.vvvv != 1111B. VEXTRACTI128/VEXTRACTI32x4/VEXTRACTI64x2/VEXTRACTI32x8/VEXTRACTI64x4—Extract Packed Integer Values Vol. 2C 5-179