PSLLDQ — Shift Double Quadword Left Logical

Opcode/Instruction Op/En 64/32 bit Mode Support CPUID Feature Flag Description
66 0F 73 /7 ib PSLLDQ xmm1, imm8 A V/V SSE2 Shift xmm1 left by imm8 bytes while shifting in 0s.
VEX.128.66.0F.WIG 73 /7 ib VPSLLDQ xmm1, xmm2, imm8 B V/V AVX Shift xmm2 left by imm8 bytes while shifting in 0s and store result in xmm1.
VEX.256.66.0F.WIG 73 /7 ib VPSLLDQ ymm1, ymm2, imm8 B V/V AVX2 Shift ymm2 left by imm8 bytes while shifting in 0s and store result in ymm1.
EVEX.128.66.0F.WIG 73 /7 ib VPSLLDQ xmm1,xmm2/ m128, imm8 C V/V AVX512VL AVX512BW Shift xmm2/m128 left by imm8 bytes while shifting in 0s and store result in xmm1.
EVEX.256.66.0F.WIG 73 /7 ib VPSLLDQ ymm1, ymm2/m256, imm8 C V/V AVX512VL AVX512BW Shift ymm2/m256 left by imm8 bytes while shifting in 0s and store result in ymm1.
EVEX.512.66.0F.WIG 73 /7 ib VPSLLDQ zmm1, zmm2/m512, imm8 C V/V AVX512BW Shift zmm2/m512 left by imm8 bytes while shifting in 0s and store result in zmm1.

Instruction Operand Encoding

Op/En Tuple Type Operand 1 Operand 2 Operand 3 Operand 4
A N/A ModRM:r/m (r, w) imm8 N/A N/A
B N/A VEX.vvvv (w) ModRM:r/m (r) imm8 N/A
C Full Mem EVEX.vvvv (w) ModRM:r/m (r) imm8 N/A

Description

Shifts the destination operand (first operand) to the left by the number of bytes specified in the count operand (second operand). The empty low-order bytes are cleared (set to all 0s). If the value specified by the count operand is greater than 15, the destination operand is set to all 0s. The count operand is an 8-bit immediate.

128-bit Legacy SSE version: The source and destination operands are the same. Bits (MAXVL-1:128) of the corresponding YMM destination register remain unchanged.

VEX.128 encoded version: The source and destination operands are XMM registers. Bits (MAXVL-1:128) of the destination YMM register are zeroed.

VEX.256 encoded version: The source operand is YMM register. The destination operand is an YMM register. Bits (MAXVL-1:256) of the corresponding ZMM register are zeroed. The count operand applies to both the low and high 128-bit lanes.

EVEX encoded versions: The source operand is a ZMM/YMM/XMM register or a 512/256/128-bit memory location. The destination operand is a ZMM/YMM/XMM register. The count operand applies to each 128-bit lanes.

Operation

VPSLLDQ (EVEX.U1.512 Encoded Version)

TEMP := COUNT
IF (TEMP > 15) THEN TEMP := 16; FI
DEST[127:0] := SRC[127:0] << (TEMP * 8)
DEST[255:128] := SRC[255:128] << (TEMP * 8)
DEST[383:256] := SRC[383:256] << (TEMP * 8)
DEST[511:384] := SRC[511:384] << (TEMP * 8)
DEST[MAXVL-1:512] := 0

VPSLLDQ (VEX.256 and EVEX.256 Encoded Version)

TEMP := COUNT
IF (TEMP > 15) THEN TEMP := 16; FI
DEST[127:0] := SRC[127:0] << (TEMP * 8)
DEST[255:128] := SRC[255:128] << (TEMP * 8)
DEST[MAXVL-1:256] := 0

VPSLLDQ (VEX.128 and EVEX.128 Encoded Version)

TEMP := COUNT
IF (TEMP > 15) THEN TEMP := 16; FI
DEST := SRC << (TEMP * 8)
DEST[MAXVL-1:128] := 0

PSLLDQ(128-bit Legacy SSE Version)

TEMP := COUNT
IF (TEMP > 15) THEN TEMP := 16; FI
DEST := DEST << (TEMP * 8)
DEST[MAXVL-1:128] (Unmodified)

Intel C/C++ Compiler Intrinsic Equivalent

(V)PSLLDQ __m128i _mm_slli_si128 ( __m128i a, int imm)
VPSLLDQ __m256i _mm256_slli_si256 ( __m256i a, const int imm)
VPSLLDQ __m512i _mm512_bslli_epi128 ( __m512i a, const int imm)

Flags Affected

None.

Numeric Exceptions

None.

Other Exceptions

Non-EVEX-encoded instruction, see Table 2-24, “Type 7 Class Exception Conditions.”

EVEX-encoded instruction, see Exceptions Type E4NF.nb in Table 2-50, “Type E4NF Class Exception Conditions.”