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mirror of https://github.com/gnss-sdr/gnss-sdr synced 2024-09-27 22:58:24 +00:00

add neon implementation

This commit is contained in:
Carles Fernandez 2016-01-24 14:30:33 +01:00
parent 2d21706041
commit 377acfc322
2 changed files with 112 additions and 0 deletions

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@ -255,4 +255,94 @@ static inline void volk_gnsssdr_16ic_x2_dot_prod_16ic_xn_u_sse2(lv_16sc_t* out,
}
#endif /* LV_HAVE_SSE2 */
#ifdef LV_HAVE_NEON
#include <arm_neon.h>
static inline void volk_gnsssdr_16ic_x2_dot_prod_16ic_xn_neon(lv_16sc_t* out, const lv_16sc_t* in_common, const lv_16sc_t** in_a, int num_a_vectors, unsigned int num_points)
{
lv_16sc_t dotProduct = lv_cmake(0,0);
const unsigned int neon_iters = num_points / 4;
const lv_16sc_t** _in_a = in_a;
const lv_16sc_t* _in_common = in_common;
lv_16sc_t* _out = out;
if (neon_iters > 0)
{
__VOLK_ATTR_ALIGNED(16) lv_16sc_t dotProductVector[4];
int16x4x2_t a_val, b_val, c_val;
//todo dyn mem reg
int16x4x2_t* accumulator;
accumulator = (int16x4x2_t*)calloc(num_a_vectors, sizeof(int16x4x2_t));
int16x4x2_t tmp_real, tmp_imag;
lv_16sc_t accum_result[4];
for(int n_vec = 0; n_vec < num_a_vectors; n_vec++)
{
accumulator[n_vec].val[0] = vdup_n_s16(0);
accumulator[n_vec].val[1] = vdup_n_s16(0);
}
for(unsigned int number = 0; number < neon_iters; number++)
{
b_val = vld2_s16((int16_t*)_in_common); //load (2 byte imag, 2 byte real) x 4 into 128 bits reg
__builtin_prefetch(_in_common + 8);
for (int n_vec = 0; n_vec < num_a_vectors; n_vec++)
{
a_val = vld2_s16((int16_t*)&(_in_a[n_vec][number*4])); //load (2 byte imag, 2 byte real) x 4 into 128 bits reg
//__builtin_prefetch(_in_a[n_vec] + 8);
// multiply the real*real and imag*imag to get real result
// a0r*b0r|a1r*b1r|a2r*b2r|a3r*b3r
tmp_real.val[0] = vmul_s16(a_val.val[0], b_val.val[0]);
// a0i*b0i|a1i*b1i|a2i*b2i|a3i*b3i
tmp_real.val[1] = vmul_s16(a_val.val[1], b_val.val[1]);
// Multiply cross terms to get the imaginary result
// a0r*b0i|a1r*b1i|a2r*b2i|a3r*b3i
tmp_imag.val[0] = vmul_s16(a_val.val[0], b_val.val[1]);
// a0i*b0r|a1i*b1r|a2i*b2r|a3i*b3r
tmp_imag.val[1] = vmul_s16(a_val.val[1], b_val.val[0]);
c_val.val[0] = vsub_s16(tmp_real.val[0], tmp_real.val[1]);
c_val.val[1] = vadd_s16(tmp_imag.val[0], tmp_imag.val[1]);
accumulator[n_vec].val[0] = vadd_s16(accumulator[n_vec].val[0], c_val.val[0]);
accumulator[n_vec].val[1] = vadd_s16(accumulator[n_vec].val[1], c_val.val[1]);
}
_in_common += 4;
}
for (int n_vec = 0; n_vec < num_a_vectors; n_vec++)
{
vst2_s16((int16_t*)dotProductVector, accumulator[n_vec]); // Store the results back into the dot product vector
dotProduct = lv_cmake(0,0);
for (int i = 0; i < 4; ++i)
{
dotProduct = lv_cmake(sat_adds16i(lv_creal(dotProduct), lv_creal(dotProductVector[i])),
sat_adds16i(lv_cimag(dotProduct), lv_cimag(dotProductVector[i])));
}
_out[n_vec] = dotProduct;
}
free(accumulator);
}
for (int n_vec = 0; n_vec < num_a_vectors; n_vec++)
{
for(unsigned int n = neon_iters * 4; n < num_points; n++)
{
lv_16sc_t tmp = in_common[n] * in_a[n_vec][n];
_out[n_vec] = lv_cmake(sat_adds16i(lv_creal(_out[n_vec]), lv_creal(tmp)),
sat_adds16i(lv_cimag(_out[n_vec]), lv_cimag(tmp)));
}
}
}
#endif /* LV_HAVE_NEON */
#endif /*INCLUDED_volk_gnsssdr_16ic_xn_dot_prod_16ic_xn_H*/

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@ -105,6 +105,28 @@ static inline void volk_gnsssdr_16ic_x2_dotprodxnpuppet_16ic_u_sse2(lv_16sc_t* r
#endif // SSE2
#ifdef LV_HAVE_NEON
static inline void volk_gnsssdr_16ic_x2_dotprodxnpuppet_16ic_neon(lv_16sc_t* result, const lv_16sc_t* local_code, const lv_16sc_t* in, unsigned int num_points)
{
int num_a_vectors = 3;
lv_16sc_t** in_a = (lv_16sc_t**)volk_gnsssdr_malloc(sizeof(lv_16sc_t*) * num_a_vectors, volk_gnsssdr_get_alignment());
for(unsigned int n = 0; n < num_a_vectors; n++)
{
in_a[n] = (lv_16sc_t*)volk_gnsssdr_malloc(sizeof(lv_16sc_t)*num_points, volk_gnsssdr_get_alignment());
memcpy(in_a[n], in, sizeof(lv_16sc_t)*num_points);
}
volk_gnsssdr_16ic_x2_dot_prod_16ic_xn_neon(result, local_code, (const lv_16sc_t**) in_a, num_a_vectors, num_points);
for(unsigned int n = 0; n < num_a_vectors; n++)
{
volk_gnsssdr_free(in_a[n]);
}
volk_gnsssdr_free(in_a);
}
#endif // NEON
#endif // INCLUDED_volk_gnsssdr_16ic_x2_dotprodxnpuppet_16ic_H