Developer Guide and Reference

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_mm_mask_i64gather_ps, _mm256_mask_i64gather_ps

Gathers 2/4 packed single-precision floating point values from memory referenced by the given base address, qword indices and scale, and using the given single-precision FP mask values. The corresponding Intel® AVX2 instruction is
VGATHERQPS
.

Syntax

extern __m128 _mm_mask_i64gather_ps(__m128 def_vals, float const * base, __m128i vindex, __m128 vmask, const int scale);
extern __m128 _mm256_mask_i64gather_ps(float const * base, __m256i vindex, __m256i vmask, const int scale);
Arguments
def_vals
the vector of single-precision FP values copied to the destination when the corresponding element of the single-precision FP mask is '
0
'.
base
the base address used to reference the loaded FP elements.
vindex
the vector of qword indices used to reference the loaded FP elements.
vmask
the vector of FP elements used as a vector mask; only the most significant bit of each data element is used as a mask.
scale
The compilation time literal constant, which is used as the vector indices scale to address the loaded elements. Possible values are one of the following: 1, 2, 4, 8.
Description
The intrinsics conditionally load 2/4 packed single-precision floating-point values from memory using qword indices and updates the destination operand. The intrinsic
_mm_mask_i64gather_ps()
also sets the upper 64-bits of the result to '
0
'.
Below is the pseudo-code for the intrinsics:
_mm_mask_i64gather_ps()
:
result[31:0] = (vmask[31]==1) ? (mem[base+vindex[63:0]*scale]) : (def_vals[31:0]); result[63:32] = (vmask[63]==1) ? (mem[base+vindex[127:64]*scale]) : (def_vals[63:32]); result[127:64] = 0;
_mm256_mask_i64gather_ps()
:
result[31:0] = (v