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	NA
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]←SRC2[127:112]
ELSE DEST[127:112]←SRC1[127:112]
IF (imm8[0] == 1) THEN DEST[143:128]←SRC2[143:128]
ELSE DEST[143:128]←SRC1[143:128]
IF (imm8[1] == 1) THEN DEST[159:144]←SRC2[159:144]
ELSE DEST[159:144]←SRC1[159:144]
IF (imm8[2] == 1) THEN DEST[175:160]←SRC2[175:160]
ELSE DEST[175:160]←SRC1[175:160]
IF (imm8[3] == 1) THEN DEST[191:176]←SRC2[191:176]
ELSE DEST[191:176]←SRC1[191:176]
IF (imm8[4] == 1) THEN DEST[207:192]←SRC2[207:192]
ELSE DEST[207:192]←SRC1[207:192]
IF (imm8[5] == 1) THEN DEST[223:208]←SRC2[223:208]
ELSE DEST[223:208]←SRC1[223:208]
IF (imm8[6] == 1) THEN DEST[239:224]←SRC2[239:224]
ELSE DEST[239:224]←SRC1[239:224]
IF (imm8[7] == 1) THEN DEST[255:240]←SRC2[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 Exceptions Type 4; additionally

#UD	If VEX.L = 1 and AVX2 = 0.