/* SoX Resampler Library Copyright (c) 2007-16 robs@users.sourceforge.net
* Licence for this file: LGPL v2.1 See LICENCE for details. */
/* Decimate by 2 using a FIR with odd length (LEN). */
/* Input must be preceded and followed by LEN >> 1 samples. */
#define COEFS ((sample_t const *)p->coefs)
#if SIMD_SSE
#define BEGINNING v4_t sum, q1, q2, t
#define ____ \
q1 = _mm_shuffle_ps(t=vLdu(input+2*j),vLdu(input+2*j+4),_MM_SHUFFLE(3,1,3,1)); \
q2 = _mm_shuffle_ps(vLdu(input-2*j-4),vLdu(input-2*j-8),_MM_SHUFFLE(1,3,1,3)); \
sum = vAdd(j? sum : vMul(vSet1(.5), t), vMul(vAdd(q1, q2), vLd(COEFS+j))); \
j += 4;
#define __ \
q1 = _mm_shuffle_ps(vLdu(input+2*j), vLdu(input-2*j-4), _MM_SHUFFLE(1,3,3,1)); \
q2 = _mm_loadl_pi(q2, (__m64*)(COEFS+j)), q2 = _mm_movelh_ps(q2, q2); \
sum = vAdd(sum, vMul(q1, q2)); \
j += 2;
#define _ \
q1 = _mm_add_ss(_mm_load_ss(input+2*j+1), _mm_load_ss(input-2*j-1)); \
sum = _mm_add_ss(sum, _mm_mul_ss(q1, _mm_load_ss(COEFS+j))); \
++j;
#define END vStorSum(output+i, sum)
/* #elif SIMD_AVX; No good solution found. */
/* #elif SIMD_NEON; No need: gcc -O3 does a good job by itself. */
#else
#define BEGINNING sample_t sum = input[0] * .5f
#define ____ __ __
#define __ _ _
#define _ sum += (input[-(2*j +1)] + input[(2*j +1)]) * COEFS[j], ++j;
#define END output[i] = sum
#endif
static void FUNCTION_H(stage_t * p, fifo_t * output_fifo)
{
sample_t const * __restrict input = stage_read_p(p);
int num_in = min(stage_occupancy(p), p->input_size);
int i, num_out = (num_in + 1) >> 1;
sample_t * __restrict output = fifo_reserve(output_fifo, num_out);
for (i = 0; i < num_out; ++i, input += 2) {
int j = 0;
BEGINNING; CONVOLVE; END;
}
fifo_read(&p->fifo, 2 * num_out, NULL);
}
#undef _
#undef __
#undef ____
#undef BEGINNING
#undef END
#undef COEFS
#undef CONVOLVE
#undef FUNCTION_H
↑ V522 There might be dereferencing of a potential null pointer 'output'.
↑ V769 The pointer in the expression could be nullptr. In such case, resulting value will be senseless and it should not be used.
↑ V769 The 'output' pointer in the 'output + i' expression could be nullptr. In such case, resulting value will be senseless and it should not be used.