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mdct: Add neon implementation of FFT

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This commit is contained in:
Antoine SOULIER
2022-05-10 13:56:39 +02:00
parent c4f48f2618
commit f182fe7e0d
6 changed files with 624 additions and 67 deletions
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15
src/mdct.c
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@@ -18,6 +18,8 @@
#include "tables.h"
#include "mdct_neon.h"
/* ----------------------------------------------------------------------------
* FFT processing
@@ -26,8 +28,9 @@
/**
* FFT 5 Points
* x, y Input and output coefficients, of size 5xn
* n Number of interleaved transform to perform
* n Number of interleaved transform to perform (n % 2 = 0)
*/
#ifndef fft_5
LC3_HOT static inline void fft_5(
const struct lc3_complex *x, struct lc3_complex *y, int n)
{
@@ -50,6 +53,7 @@ LC3_HOT static inline void fft_5(
{ x[2*n].re - x[3*n].re, x[2*n].im - x[3*n].im };
y[0].re = x[0].re + s14.re + s23.re;
y[0].im = x[0].im + s14.im + s23.im;
y[1].re = x[0].re + s14.re * cos1 - d14.im * sin1
@@ -77,6 +81,7 @@ LC3_HOT static inline void fft_5(
+ s23.im * cos2 - d23.re * sin2;
}
}
#endif /* fft_5 */
/**
* FFT Butterfly 3 Points
@@ -84,6 +89,7 @@ LC3_HOT static inline void fft_5(
* twiddles Twiddles factors, determine size of transform
* n Number of interleaved transforms
*/
#ifndef fft_bf3
LC3_HOT static inline void fft_bf3(
const struct lc3_fft_bf3_twiddles *twiddles,
const struct lc3_complex *x, struct lc3_complex *y, int n)
@@ -95,8 +101,7 @@ LC3_HOT static inline void fft_bf3(
const struct lc3_complex *x0 = x, *x1 = x0 + n*n3, *x2 = x1 + n*n3;
struct lc3_complex *y0 = y, *y1 = y0 + n3, *y2 = y1 + n3;
for (int i = 0; i < n; i++, y0 += 3*n3, y1 += 3*n3, y2 += 3*n3) {
for (int i = 0; i < n; i++, y0 += 3*n3, y1 += 3*n3, y2 += 3*n3)
for (int j = 0; j < n3; j++, x0++, x1++, x2++) {
y0[j].re = x0->re + x1->re * w0[j][0].re - x1->im * w0[j][0].im
@@ -117,8 +122,8 @@ LC3_HOT static inline void fft_bf3(
y2[j].im = x0->im + x1->im * w2[j][0].re + x1->re * w2[j][0].im
+ x2->im * w2[j][1].re + x2->re * w2[j][1].im;
}
}
}
#endif /* fft_bf3 */
/**
* FFT Butterfly 2 Points
@@ -126,6 +131,7 @@ LC3_HOT static inline void fft_bf3(
* x, y Input and output coefficients
* n Number of interleaved transforms
*/
#ifndef fft_bf2
LC3_HOT static inline void fft_bf2(
const struct lc3_fft_bf2_twiddles *twiddles,
const struct lc3_complex *x, struct lc3_complex *y, int n)
@@ -148,6 +154,7 @@ LC3_HOT static inline void fft_bf2(
}
}
}
#endif /* fft_bf2 */
/**
* Perform FFT