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adding neon implementation

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This commit is contained in:
Carles Fernandez
2016-01-22 12:29:08 +01:00
parent 642018bada
commit 7bf4bfd7dc
1 changed files with 63 additions and 0 deletions
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63
src/algorithms/libs/volk_gnsssdr_module/volk_gnsssdr/kernels/volk_gnsssdr/volk_gnsssdr_32fc_convert_16ic.h
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@@ -249,6 +249,69 @@ static inline void volk_gnsssdr_32fc_convert_16ic_a_sse(lv_16sc_t* outputVector,
}
#endif /* LV_HAVE_SSE */
#ifdef LV_HAVE_NEON
#include <arm_neon.h>
/*!
\brief Converts a float vector of 64 bits (32 bits each part) into a 32 integer vector (16 bits each part)
\param inputVector The floating point input data buffer
\param outputVector The 16 bit output data buffer
\param num_points The number of data values to be converted
*/
static inline void volk_gnsssdr_32fc_convert_16ic_neon(lv_16sc_t* outputVector, const lv_32fc_t* inputVector, unsigned int num_points)
{
const unsigned int neon_iters = num_points / 4;
float32_t* inputVectorPtr = (float32_t*)inputVector;
int16_t* outputVectorPtr = (int16_t*)outputVector;
float32x4_t min_val = vmovq_n_f32(SHRT_MIN);
float32x4_t max_val = vmovq_n_f32(SHRT_MAX);
float32x4_t half = vdupq_n_f32(0.5f);
float32x4_t ret1, ret2, a, b, sign, PlusHalf, Round;
int32x4_t toint_a, toint_b;
int16x4_t intInputVal1, intInputVal2;
int16x8_t res;
for(unsigned int i = 0;i < neon_iters; i++)
{
a = vld1q_f32((const float32_t*)(inputVectorPtr)); inputVectorPtr += 4;
b = vld1q_f32((const float32_t*)(inputVectorPtr)); inputVectorPtr += 4;
ret1 = vmaxq_f32(vminq_f32(a, max_val), min_val);
ret2 = vmaxq_f32(vminq_f32(b, max_val), min_val);
/* in __aarch64__ we can do that with vcvtaq_s32_f32(ret1); vcvtaq_s32_f32(ret2); */
sign = vcvtq_f32_u32((vshrq_n_u32(vreinterpretq_u32_f32(ret1), 31)));
PlusHalf = vaddq_f32(ret1, half);
Round = vsubq_f32(PlusHalf, sign);
toint_a = vcvtq_s32_f32(Round);
sign = vcvtq_f32_u32((vshrq_n_u32(vreinterpretq_u32_f32(ret2), 31)));
PlusHalf = vaddq_f32(ret2, half);
Round = vsubq_f32(PlusHalf, sign);
toint_b = vcvtq_s32_f32(Round);
intInputVal1 = vqmovn_s32(toint_a);
intInputVal2 = vqmovn_s32(toint_b);
res = vcombine_s16(intInputVal1, intInputVal2);
vst1q_s16((int16_t*)outputVectorPtr, res);
outputVectorPtr += 8;
}
for(unsigned int i = neon * 8; i < num_points * 2; i++)
{
if(inputVectorPtr[i] > SHRT_MAX)
inputVectorPtr[i] = (int16_t)SHRT_MAX;
else if(inputVectorPtr[i] < SHRT_MIN)
inputVectorPtr[i] = (int16_t)SHRT_MIN;
*outputVectorPtr++ = (int16_t)rintf(*inputVectorPtr++);
}
}
#endif /* LV_HAVE_NEON */
#ifdef LV_HAVE_GENERIC
/*!
\brief Converts a float vector of 64 bits (32 bits each part) into a 32 integer vector (16 bits each part)