PBLENDW
Blend Packed Words
| Opcode/Instruction | Op/En | 64/32 bit Mode Support | CPUID Feature Flag | Description |
|---|---|---|---|---|
| 66 0F 3A 0E /r ib PBLENDW xmm1, xmm2/m128, imm8 | RMI | V/V | SSE4_1 | Select words from xmm1 and xmm2/m128 from mask specified in imm8 and store the values into xmm1. |
| VEX.128.66.0F3A.WIG 0E /r ib VPBLENDW xmm1, xmm2, xmm3/m128, imm8 | RVMI | V/V | AVX | Select words from xmm2 and xmm3/m128 from mask specified in imm8 and store the values into xmm1. |
| VEX.256.66.0F3A.WIG 0E /r ib VPBLENDW ymm1, ymm2, ymm3/m256, imm8 | RVMI | V/V | AVX2 | Select words from ymm2 and ymm3/m256 from mask specified in imm8 and store the values into ymm1. |
Instruction Operand Encoding
| Op/En | Operand 1 | Operand 2 | Operand 3 | Operand 4 |
|---|---|---|---|---|
| RMI | ModRM:reg (r, w) | ModRM:r/m (r) | imm8 | N/A |
| RVMI | ModRM:reg (w) | VEX.vvvv (r) | ModRM:r/m (r) | imm8 |
Description
Words from the source operand (second operand) are conditionally written to the destination operand (first operand) depending on bits in the immediate operand (third operand). The immediate bits (bits 7:0) form a mask that determines whether the corresponding word in the destination is copied from the source. If a bit in the mask, corresponding to a word, is “1”, then the word is copied, else the word element in the destination operand is unchanged.
128-bit Legacy SSE version: The second source operand can be an XMM register or a 128-bit memory location. The first source and destination operands are XMM registers. Bits (MAXVL-1:128) of the corresponding YMM destination register remain unchanged.
VEX.128 encoded version: The second source operand can be an XMM register or a 128-bit memory location. The first source and destination operands are XMM registers. Bits (MAXVL-1:128) of the corresponding YMM register are zeroed.
VEX.256 encoded version: The first source operand is a YMM register. The second source operand is a YMM register or a 256-bit memory location. The destination operand is a YMM register.
Operation
PBLENDW (128-bit Legacy SSE Version)
IF (imm8[0] = 1) THEN DEST[15:0] := SRC[15:0]
ELSE DEST[15:0] := DEST[15:0]
IF (imm8[1] = 1) THEN DEST[31:16] := SRC[31:16]
ELSE DEST[31:16] := DEST[31:16]
IF (imm8[2] = 1) THEN DEST[47:32] := SRC[47:32]
ELSE DEST[47:32] := DEST[47:32]
IF (imm8[3] = 1) THEN DEST[63:48] := SRC[63:48]
ELSE DEST[63:48] := DEST[63:48]
IF (imm8[4] = 1) THEN DEST[79:64] := SRC[79:64]
ELSE DEST[79:64] := DEST[79:64]
IF (imm8[5] = 1) THEN DEST[95:80] := SRC[95:80]
ELSE DEST[95:80] := DEST[95:80]
IF (imm8[6] = 1) THEN DEST[111:96] := SRC[111:96]
ELSE DEST[111:96] := DEST[111:96]
IF (imm8[7] = 1) THEN DEST[127:112] := SRC[127:112]
ELSE DEST[127:112] := DEST[127:112]
VPBLENDW (VEX.128 Encoded Version)
IF (imm8[0] = 1) THEN DEST[15:0] := SRC2[15:0]
ELSE DEST[15:0] := SRC1[15:0]
IF (imm8[1] = 1) THEN DEST[31:16] := SRC2[31:16]
ELSE DEST[31:16] := SRC1[31:16]
IF (imm8[2] = 1) THEN DEST[47:32] := SRC2[47:32]
ELSE DEST[47:32] := SRC1[47:32]
IF (imm8[3] = 1) THEN DEST[63:48] := SRC2[63:48]
ELSE DEST[63:48] := SRC1[63:48]
IF (imm8[4] = 1) THEN DEST[79:64] := SRC2[79:64]
ELSE DEST[79:64] := SRC1[79:64]
IF (imm8[5] = 1) THEN DEST[95:80] := SRC2[95:80]
ELSE DEST[95:80] := SRC1[95:80]
IF (imm8[6] = 1) THEN DEST[111:96] := SRC2[111:96]
ELSE DEST[111:96] := SRC1[111:96]
IF (imm8[7] = 1) THEN DEST[127:112] := SRC2[127:112]
ELSE DEST[127:112] := SRC1[127:112]
DEST[MAXVL-1:128] := 0
VPBLENDW (VEX.256 Encoded Version)
IF (imm8[0] == 1) THEN DEST[15:0] := SRC2[15:0]
ELSE DEST[15:0] := SRC1[15:0]
IF (imm8[1] == 1) THEN DEST[31:16] := SRC2[31:16]
ELSE DEST[31:16] := SRC1[31:16]
IF (imm8[2] == 1) THEN DEST[47:32] := SRC2[47:32]
ELSE DEST[47:32] := SRC1[47:32]
IF (imm8[3] == 1) THEN DEST[63:48] := SRC2[63:48]
ELSE DEST[63:48] := SRC1[63:48]
IF (imm8[4] == 1) THEN DEST[79:64] := SRC2[79:64]
ELSE DEST[79:64] := SRC1[79:64]
IF (imm8[5] == 1) THEN DEST[95:80] := SRC2[95:80]
ELSE DEST[95:80] := SRC1[95:80]
IF (imm8[6] == 1) THEN DEST[111:96] := SRC2[111:96]
ELSE DEST[111:96] := SRC1[111:96]
IF (imm8[7] == 1) THEN DEST[127:112]
ELSE DEST[127:112] := SRC1[127:112]
IF (imm8[0] == 1) THEN DEST[143:128]
ELSE DEST[143:128] := SRC1[143:128]
IF (imm8[1] == 1) THEN DEST[159:144]
ELSE DEST[159:144] := SRC1[159:144]
IF (imm8[2] == 1) THEN DEST[175:160]
ELSE DEST[175:160] := SRC1[175:160]
IF (imm8[3] == 1) THEN DEST[191:176]
ELSE DEST[191:176] := SRC1[191:176]
IF (imm8[4] == 1) THEN DEST[207:192]
ELSE DEST[207:192] := SRC1[207:192]
IF (imm8[5] == 1) THEN DEST[223:208]
ELSE DEST[223:208] := SRC1[223:208]
IF (imm8[6] == 1) THEN DEST[239:224]
ELSE DEST[239:224] := SRC1[239:224]
IF (imm8[7] == 1) THEN DEST[255:240]
ELSE DEST[255:240] := SRC1[255:240]
Intel C/C++ Compiler Intrinsic Equivalent
(V)PBLENDW __m128i _mm_blend_epi16 (__m128i v1, __m128i v2, const int mask);
VPBLENDW __m256i _mm256_blend_epi16 (__m256i v1, __m256i v2, const int mask)
Flags Affected
None.
SIMD Floating-Point Exceptions
None.
Other Exceptions
See Table 2-21, “Type 4 Class Exception Conditions,” additionally:
| #UD | If VEX.L = 1 and AVX2 = 0. |
|---|
This UNOFFICIAL, mechanically-separated, non-verified reference is provided for convenience, but it may be incomplete or broken in various obvious or non-obvious ways. Refer to Intel® 64 and IA-32 Architectures Software Developer’s Manual for anything serious.