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Removed nonsense register modifier

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master
boblark 4 weeks ago
parent 8f091dad1e
commit 5113b5394b
1 changed files with 49 additions and 48 deletions
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  1. 97
      utility/BTNRH_rfft.cpp

97
utility/BTNRH_rfft.cpp
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@ -18,18 +18,19 @@ namespace BTNRH_FFT {
ilog2(int n) ilog2(int n)
{ {
int m; int m;
for (m = 1; m < 32; m++) for (m = 1; m < 32; m++)
if (n == (1 << m)) if (n == (1 << m))
return (m); return (m);
return (-1); return (-1);
} }
static __inline int static __inline int
bitrev(int ii, int m) bitrev(int ii, int m)
{ {
register int jj; // Was: register int jj; RSL 9 Oct 2024
int jj;
jj = ii & 1; jj = ii & 1;
--m; --m;
while (--m > 0) { while (--m > 0) {
@ -39,26 +40,26 @@ namespace BTNRH_FFT {
} }
return (jj); return (jj);
} }
static __inline void static __inline void
rad2(int ii, float *x0, float *x1) rad2(int ii, float *x0, float *x1)
{ {
int k; int k;
float t; float t;
for (k = 0; k < ii; k++) { for (k = 0; k < ii; k++) {
t = x0[k] + x1[k]; t = x0[k] + x1[k];
x1[k] = x0[k] - x1[k]; x1[k] = x0[k] - x1[k];
x0[k] = t; x0[k] = t;
} }
} }
static __inline void static __inline void
reorder1(int m, float *x) reorder1(int m, float *x)
{ {
int j, k, kl, n; int j, k, kl, n;
float t; float t;
k = 4; k = 4;
kl = 2; kl = 2;
n = 1 << m; n = 1 << m;
@ -75,13 +76,13 @@ namespace BTNRH_FFT {
} }
} }
} }
static __inline void static __inline void
reorder2(int m, float *x) reorder2(int m, float *x)
{ {
int ji, ij, n; int ji, ij, n;
float t; float t;
n = 1 << m; n = 1 << m;
for (ij = 0; ij <= (n - 2); ij += 2) { for (ij = 0; ij <= (n - 2); ij += 2) {
ji = bitrev(ij >> 1, m) << 1; ji = bitrev(ij >> 1, m) << 1;
@ -95,11 +96,11 @@ namespace BTNRH_FFT {
} }
} }
} }
/***********************************************************/ /***********************************************************/
// rcfft // rcfft
static void static void
rcrad4(int ii, int nn, rcrad4(int ii, int nn,
float *x0, float *x1, float *x2, float *x3, float *x0, float *x1, float *x2, float *x3,
@ -109,7 +110,7 @@ namespace BTNRH_FFT {
float c1, c2, c3, s1, s2, s3, pr, pi, r1, r5; float c1, c2, c3, s1, s2, s3, pr, pi, r1, r5;
float t0, t1, t2, t3, t4, t5, t6, t7; float t0, t1, t2, t3, t4, t5, t6, t7;
int i0, i4, j, j0, ji, jl, jr, jlast, k, k0, kl, m, n, ni; int i0, i4, j, j0, ji, jl, jr, jlast, k, k0, kl, m, n, ni;
n = nn / 4; n = nn / 4;
for (m = 1; (1 << m) < n; m++) for (m = 1; (1 << m) < n; m++)
continue; continue;
@ -186,19 +187,19 @@ namespace BTNRH_FFT {
} }
} }
} }
//----------------------------------------------------------- //-----------------------------------------------------------
static int static int
rcfft2(float *x, int m) rcfft2(float *x, int m)
{ {
int ii, nn, m2, it, n; int ii, nn, m2, it, n;
n = 1 << m;; n = 1 << m;;
m2 = m / 2; m2 = m / 2;
// radix 2 // radix 2
if (m <= m2 * 2) { if (m <= m2 * 2) {
nn = 1; nn = 1;
} else { } else {
@ -206,9 +207,9 @@ namespace BTNRH_FFT {
ii = n / nn; ii = n / nn;
rad2(ii, x, x + ii); rad2(ii, x, x + ii);
} }
// radix 4 // radix 4
if (m2 != 0) { if (m2 != 0) {
for (it = 0; it < m2; it++) { for (it = 0; it < m2; it++) {
nn = nn * 4; nn = nn * 4;
@ -217,9 +218,9 @@ namespace BTNRH_FFT {
x, x + ii, x + 2 * ii, x + 3 * ii); x, x + ii, x + 2 * ii, x + 3 * ii);
} }
} }
// re-order // re-order
reorder1(m, x); reorder1(m, x);
reorder2(m, x); reorder2(m, x);
for (it = 3; it < n; it += 2) for (it = 3; it < n; it += 2)
@ -227,14 +228,14 @@ namespace BTNRH_FFT {
x[n] = x[1]; x[n] = x[1];
x[1] = 0.0; x[1] = 0.0;
x[n + 1] = 0.0; x[n + 1] = 0.0;
return (0); return (0);
} }
/***********************************************************/ /***********************************************************/
// rcfft // rcfft
static void static void
crrad4(int jj, int nn, crrad4(int jj, int nn,
float *x0, float *x1, float *x2, float *x3, float *x0, float *x1, float *x2, float *x3,
@ -244,7 +245,7 @@ namespace BTNRH_FFT {
float c1, c2, c3, s1, s2, s3; float c1, c2, c3, s1, s2, s3;
float t0, t1, t2, t3, t4, t5, t6, t7; float t0, t1, t2, t3, t4, t5, t6, t7;
int ii, j, j0, ji, jr, jl, jlast, j4, k, k0, kl, m, n, ni; int ii, j, j0, ji, jr, jl, jlast, j4, k, k0, kl, m, n, ni;
tpiovn = 2 * M_PI / nn; tpiovn = 2 * M_PI / nn;
ji = 3; ji = 3;
jl = 2; jl = 2;
@ -317,27 +318,27 @@ namespace BTNRH_FFT {
} }
} }
} }
//----------------------------------------------------------- //-----------------------------------------------------------
static int static int
crfft2(float *x, int m) crfft2(float *x, int m)
{ {
int n, i, it, nn, jj, m2; int n, i, it, nn, jj, m2;
n = 1 << m; n = 1 << m;
x[1] = x[n]; x[1] = x[n];
m2 = m / 2; m2 = m / 2;
// re-order // re-order
for (i = 3; i < n; i += 2) for (i = 3; i < n; i += 2)
x[i] = -x[i]; x[i] = -x[i];
reorder2(m, x); reorder2(m, x);
reorder1(m, x); reorder1(m, x);
// radix 4 // radix 4
if (m2 != 0) { if (m2 != 0) {
nn = 4 * n; nn = 4 * n;
for (it = 0; it < m2; it++) { for (it = 0; it < m2; it++) {
@ -347,39 +348,39 @@ namespace BTNRH_FFT {
x, x + jj, x + 2 * jj, x + 3 * jj); x, x + jj, x + 2 * jj, x + 3 * jj);
} }
} }
// radix 2 // radix 2
if (m > m2 * 2) { if (m > m2 * 2) {
jj = n / 2; jj = n / 2;
rad2(jj, x, x + jj); rad2(jj, x, x + jj);
} }
return (0); return (0);
} }
/***********************************************************/ /***********************************************************/
// real-to-complex FFT // real-to-complex FFT
//FUNC(void) //FUNC(void)
void cha_fft_rc(float *x, int n) void cha_fft_rc(float *x, int n)
{ {
int m; int m;
// assume n is a power of two // assume n is a power of two
m = ilog2(n); m = ilog2(n);
rcfft2(x, m); rcfft2(x, m);
} }
// complex-to-real inverse FFT // complex-to-real inverse FFT
//FUNC(void) //FUNC(void)
void cha_fft_cr(float *x, int n) void cha_fft_cr(float *x, int n)
{ {
int i, m; int i, m;
// assume n is a power of two // assume n is a power of two
m = ilog2(n); m = ilog2(n);
crfft2(x, m); crfft2(x, m);
// scale inverse by 1/n // scale inverse by 1/n
@ -390,4 +391,4 @@ namespace BTNRH_FFT {
}; };
//endif //endif

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