_mm_mask_i64gather_epi64
Classification
Header File
Instruction
VPGATHERQQ xmm, vm64x, xmm
Synopsis
_mm_mask_i64gather_epi64(__m128i src, __int64 const* base_addr, __m128i vindex, __m128i mask, const int scale);
Description
Gather 64-bit integers from memory using 64-bit indices. 64-bit elements are loaded from addresses starting at "base_addr" and offset by each 64-bit element in "vindex" (each index is scaled by the factor in "scale"). Gathered elements are merged into "dst" using "mask" (elements are copied from "src" when the highest bit is not set in the corresponding element). "scale" should be 1, 2, 4 or 8.
Operation
FOR j := 0 to 1
i := j*64
m := j*64
IF mask[i+63]
addr := base_addr + vindex[m+63:m] * ZeroExtend64(scale) * 8
dst[i+63:i] := MEM[addr+63:addr]
ELSE
dst[i+63:i] := src[i+63:i]
FI
ENDFOR
mask[MAX:128] := 0
dst[MAX:128] := 0