PBLENDW

Blend Packed Words

Opcodes

Hex Mnemonic Encoding Long Mode Legacy Mode Description
66 0F 3A 0E /r ib PBLENDW xmm1, xmm2/m128, imm8 A Valid Valid Select words from xmm1 and xmm2/m128 from mask specified in imm8 and store the values into xmm1.

Instruction Operand Encoding

Op/En Operand 0 Operand 1 Operand 2 Operand 3
A NA imm8 ModRM:r/m (r) ModRM:reg (r, w)

Description

Conditionally copies word elements from the source operand (second operand) to the destination operand (first operand) depending on the immediate byte (third operand). Each bit of Imm8 correspond to a word element.

If a bit is "1", then the corresponding word element in the source operand is copied to the destination, else the word element in the destination operand is left unchanged.

Pseudo Code

IF (imm8[0] = 1)
	DEST[15:0] = SRC[15:0];
ELSE
	DEST[15:0] = DEST[15:0];
FI;
IF (imm8[1] = 1)
	DEST[31:16] = SRC[31:16];
ELSE
	DEST[31:16] = DEST[31:16]);
FI;
IF (imm8[2] = 1)
	DEST[47:32] = SRC[47:32];
ELSE
	DEST[47:32] = DEST[47:32];
FI;
IF (imm8[3] = 1)
	DEST[63:48] = SRC[63:48];
ELSE
	DEST[63:48] = DEST[63:48];
FI;
IF (imm8[4] = 1)
	DEST[79:64] = SRC[79:64];
ELSE
	DEST[79:64] = DEST[79:64];
FI;
IF (imm8[5] = 1)
	DEST[95:80] = SRC[95:80];
ELSE
	DEST[95:80] = DEST[95:80];
FI;
IF (imm8[6] = 1)
	DEST[111:96] = SRC[111:96];
ELSE
	DEST[111:96] = DEST[111:96];
FI;
IF (imm8[7] = 1)
	DEST[127:112] = SRC[127:112];
ELSE
	DEST[127:112] = DEST[127:112];
FI;

Flags Affected

None

Exceptions

64-Bit Mode Exceptions

Exception Description
#UD If EM in CR0 is set. If OSFXSR in CR4 is 0. If CPUID feature flag ECX.SSE4_1 is 0. If LOCK prefix is used. Either the prefix REP (F3h) or REPN (F2H) is used.
#NM If TS in CR0 is set.
#PF(fault-code) For a page fault.
#SS(0) If a memory address referencing the SS segment is in a non- canonical form.
#GP(0) If the memory address is in a non-canonical form. If a memory operand is not aligned on a 16-byte boundary, regardless of segment.

Compatibility Mode Exceptions

Same exceptions as in Protected Mode.

Virtual-8086 Mode Exceptions

Exception Description
#PF(fault-code) For a page fault.
Same exceptions as in Real Address Mode.

Real-Address Mode Exceptions

Exception Description
#UD If CR0.EM[bit 2] = 1. If CR4.OSFXSR[bit 9] = 0. If CPUID.01H:ECX.SSE4_1[bit 19] = 0. If LOCK prefix is used. Either the prefix REP (F3h) or REPN (F2H) is used.
#NM If CR0.TS[bit 3] = 1.
#GP(0) if any part of the operand lies outside of the effective address space from 0 to 0FFFFH. If a memory operand is not aligned on a 16-byte boundary, regardless of segment.

Protected Mode Exceptions

Exception Description
#UD If CR0.EM[bit 2] = 1. If CR4.OSFXSR[bit 9] = 0. If CPUID.01H:ECX.SSE4_1[bit 19] = 0. If LOCK prefix is used. Either the prefix REP (F3h) or REPN (F2H) is used.
#NM If CR0.TS[bit 3] = 1.
#PF(fault-code) For a page fault.
#SS(0) For an illegal address in the SS segment.
#GP(0) For an illegal memory operand effective address in the CS, DS, ES, FS, or GS segments. If a memory operand is not aligned on a 16-byte boundary, regardless of segment.