MOVLPD—Move Low Packed Double-Precision Floating-Point Value

Opcode/Instruction	Op / En	64/32 bit Mode Support	CPUID Feature Flag	Description
66 0F 12 /r MOVLPD xmm1, m64	RM	V/V	SSE2	Move double-precision floating-point value from m64 to low quadword of xmm1.
VEX.NDS.128.66.0F.WIG 12 /r VMOVLPD xmm2, xmm1, m64	RVM	V/V	AVX	Merge double-precision floating-point value from m64 and the high quadword of xmm1.
EVEX.NDS.128.66.0F.W1 12 /r VMOVLPD xmm2, xmm1, m64	T1S	V/V	AVX512F	Merge double-precision floating-point value from m64 and the high quadword of xmm1.
66 0F 13/r MOVLPD m64, xmm1	MR	V/V	SSE2	Move double-precision floating-point value from low quadword of xmm1 to m64.
VEX.128.66.0F.WIG 13/r VMOVLPD m64, xmm1	MR	V/V	AVX	Move double-precision floating-point value from low quadword of xmm1 to m64.
EVEX.128.66.0F.W1 13/r VMOVLPD m64, xmm1	T1S-MR	V/V	AVX512F	Move double-precision floating-point value from low quadword of xmm1 to m64.

Instruction Operand Encoding

Op/En	Operand 1	Operand 2	Operand 3	Operand 4
RM	ModRM:reg (r, w)	ModRM:r/m (r)	NA	NA
RVM	ModRM:r/m (r)	VEX.vvvv	ModRM:r/m (r)	NA
MR	ModRM:r/m (w)	ModRM:reg (r)	NA	NA
T1S	ModRM:reg (w)	EVEX.vvvv	ModRM:r/m (r)	NA
T1S-MR	ModRM:r/m (w)	ModRM:reg (r)	NA	NA

Description

This instruction cannot be used for register to register or memory to memory moves.

128-bit Legacy SSE load:

Moves a double-precision floating-point value from the source 64-bit memory operand and stores it in the low 64-bits of the destination XMM register. The upper 64bits of the XMM register are preserved. Bits (MAX_VL-1:128) of the corresponding destination register are preserved.

VEX.128 & EVEX encoded load:

Loads a double-precision floating-point value from the source 64-bit memory operand (third operand), merges it with the upper 64-bits of the first source XMM register (second operand), and stores it in the low 128-bits of the destination XMM register (first operand). Bits (MAX_VL-1:128) of the corresponding destination register are zeroed.

128-bit store:

Stores a double-precision floating-point value from the low 64-bits of the XMM register source (second operand) to the 64-bit memory location (first operand).

Note: VMOVLPD (store) (VEX.128.66.0F 13 /r) is legal and has the same behavior as the existing 66 0F 13 store. For VMOVLPD (store) VEX.vvvv and EVEX.vvvv are reserved and must be 1111b otherwise instruction will #UD.

If VMOVLPD is encoded with VEX.L or EVEX.L’L= 1, an attempt to execute the instruction encoded with VEX.L or EVEX.L’L= 1 will cause an #UD exception.

Operation

MOVLPD (128-bit Legacy SSE load)

DEST[63:0] (cid:197) SRC[63:0]
DEST[MAX_VL-1:64] (Unmodified)

VMOVLPD (VEX.128 & EVEX encoded load)

DEST[63:0] (cid:197) SRC2[63:0]
DEST[127:64] (cid:197) SRC1[127:64]
DEST[MAX_VL-1:128] (cid:197) 0

VMOVLPD (store)

DEST[63:0] (cid:197) SRC[63:0]

Intel C/C++ Compiler Intrinsic Equivalent

MOVLPD __m128d _mm_loadl_pd ( __m128d a, double *p)
MOVLPD void _mm_storel_pd (double *p, __m128d a)

SIMD Floating-Point Exceptions

None

Other Exceptions

Non-EVEX-encoded instruction, see Exceptions Type 5; additionally

#UD	If VEX.L = 1. EVEX-encoded instruction, see Exceptions Type E9NF.