Visible to Intel only — GUID: GUID-2D52EB71-CADA-420A-B1B3-94BBE6F660F5
Visible to Intel only — GUID: GUID-2D52EB71-CADA-420A-B1B3-94BBE6F660F5
_mm_i64gather_ps, _mm256_i64gather_ps
Gathers 2/4 packed single-precision floating point values from memory referenced by the given base address, qword indices and scale. The corresponding Intel® AVX2 instruction is VGATHERQPS.
Syntax
extern __m128 _mm_mask_i64gather_ps(float const * base, __m128i vindex, const int scale); |
extern __m128 _mm256_mask_i64gather_ps(float const * base, __m256i vindex, const int scale); |
Arguments
base |
the base address used to reference the loaded FP elements. |
vindex |
the vector of qword indices used to reference the loaded FP elements. |
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 load 2/4 packed single-precision floating-point values from memory using qword indices and updates the destination operand. The intrinsic _mm_i64gather_ps() also sets the upper 64-bits of the result to '0'.
Below is the pseudo-code for the intrinsics:
_mm_i64gather_ps():
result[31:0] = mem[base+vindex[63:0]*scale]; result[63:32] = mem[base+vindex[127:64]*scale]; result[127:64] = 0;
_mm256_i64gather_ps():
result[31:0] = mem[base+vindex[63:0]*scale]; result[63:32] = mem[base+vindex[127:64]*scale]; result[95:64] = mem[base+vindex[191:128]*scale]; result[127:96] = mem[base+vindex[255:192]*scale];
Returns
A 128/256-bit vector with unconditionally gathered single-precision FP values.