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-rw-r--r--third_party/webrtc/src/webrtc/common_audio/signal_processing/complex_fft.c298
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diff --git a/third_party/webrtc/src/webrtc/common_audio/signal_processing/complex_fft.c b/third_party/webrtc/src/webrtc/common_audio/signal_processing/complex_fft.c
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+++ b/third_party/webrtc/src/webrtc/common_audio/signal_processing/complex_fft.c
@@ -0,0 +1,298 @@
+/*
+ * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+
+/*
+ * This file contains the function WebRtcSpl_ComplexFFT().
+ * The description header can be found in signal_processing_library.h
+ *
+ */
+
+#include "webrtc/common_audio/signal_processing/complex_fft_tables.h"
+#include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
+
+#define CFFTSFT 14
+#define CFFTRND 1
+#define CFFTRND2 16384
+
+#define CIFFTSFT 14
+#define CIFFTRND 1
+
+
+int WebRtcSpl_ComplexFFT(int16_t frfi[], int stages, int mode)
+{
+ int i, j, l, k, istep, n, m;
+ int16_t wr, wi;
+ int32_t tr32, ti32, qr32, qi32;
+
+ /* The 1024-value is a constant given from the size of kSinTable1024[],
+ * and should not be changed depending on the input parameter 'stages'
+ */
+ n = 1 << stages;
+ if (n > 1024)
+ return -1;
+
+ l = 1;
+ k = 10 - 1; /* Constant for given kSinTable1024[]. Do not change
+ depending on the input parameter 'stages' */
+
+ if (mode == 0)
+ {
+ // mode==0: Low-complexity and Low-accuracy mode
+ while (l < n)
+ {
+ istep = l << 1;
+
+ for (m = 0; m < l; ++m)
+ {
+ j = m << k;
+
+ /* The 256-value is a constant given as 1/4 of the size of
+ * kSinTable1024[], and should not be changed depending on the input
+ * parameter 'stages'. It will result in 0 <= j < N_SINE_WAVE/2
+ */
+ wr = kSinTable1024[j + 256];
+ wi = -kSinTable1024[j];
+
+ for (i = m; i < n; i += istep)
+ {
+ j = i + l;
+
+ tr32 = (wr * frfi[2 * j] - wi * frfi[2 * j + 1]) >> 15;
+
+ ti32 = (wr * frfi[2 * j + 1] + wi * frfi[2 * j]) >> 15;
+
+ qr32 = (int32_t)frfi[2 * i];
+ qi32 = (int32_t)frfi[2 * i + 1];
+ frfi[2 * j] = (int16_t)((qr32 - tr32) >> 1);
+ frfi[2 * j + 1] = (int16_t)((qi32 - ti32) >> 1);
+ frfi[2 * i] = (int16_t)((qr32 + tr32) >> 1);
+ frfi[2 * i + 1] = (int16_t)((qi32 + ti32) >> 1);
+ }
+ }
+
+ --k;
+ l = istep;
+
+ }
+
+ } else
+ {
+ // mode==1: High-complexity and High-accuracy mode
+ while (l < n)
+ {
+ istep = l << 1;
+
+ for (m = 0; m < l; ++m)
+ {
+ j = m << k;
+
+ /* The 256-value is a constant given as 1/4 of the size of
+ * kSinTable1024[], and should not be changed depending on the input
+ * parameter 'stages'. It will result in 0 <= j < N_SINE_WAVE/2
+ */
+ wr = kSinTable1024[j + 256];
+ wi = -kSinTable1024[j];
+
+#ifdef WEBRTC_ARCH_ARM_V7
+ int32_t wri = 0;
+ __asm __volatile("pkhbt %0, %1, %2, lsl #16" : "=r"(wri) :
+ "r"((int32_t)wr), "r"((int32_t)wi));
+#endif
+
+ for (i = m; i < n; i += istep)
+ {
+ j = i + l;
+
+#ifdef WEBRTC_ARCH_ARM_V7
+ register int32_t frfi_r;
+ __asm __volatile(
+ "pkhbt %[frfi_r], %[frfi_even], %[frfi_odd],"
+ " lsl #16\n\t"
+ "smlsd %[tr32], %[wri], %[frfi_r], %[cfftrnd]\n\t"
+ "smladx %[ti32], %[wri], %[frfi_r], %[cfftrnd]\n\t"
+ :[frfi_r]"=&r"(frfi_r),
+ [tr32]"=&r"(tr32),
+ [ti32]"=r"(ti32)
+ :[frfi_even]"r"((int32_t)frfi[2*j]),
+ [frfi_odd]"r"((int32_t)frfi[2*j +1]),
+ [wri]"r"(wri),
+ [cfftrnd]"r"(CFFTRND));
+#else
+ tr32 = wr * frfi[2 * j] - wi * frfi[2 * j + 1] + CFFTRND;
+
+ ti32 = wr * frfi[2 * j + 1] + wi * frfi[2 * j] + CFFTRND;
+#endif
+
+ tr32 >>= 15 - CFFTSFT;
+ ti32 >>= 15 - CFFTSFT;
+
+ qr32 = ((int32_t)frfi[2 * i]) << CFFTSFT;
+ qi32 = ((int32_t)frfi[2 * i + 1]) << CFFTSFT;
+
+ frfi[2 * j] = (int16_t)(
+ (qr32 - tr32 + CFFTRND2) >> (1 + CFFTSFT));
+ frfi[2 * j + 1] = (int16_t)(
+ (qi32 - ti32 + CFFTRND2) >> (1 + CFFTSFT));
+ frfi[2 * i] = (int16_t)(
+ (qr32 + tr32 + CFFTRND2) >> (1 + CFFTSFT));
+ frfi[2 * i + 1] = (int16_t)(
+ (qi32 + ti32 + CFFTRND2) >> (1 + CFFTSFT));
+ }
+ }
+
+ --k;
+ l = istep;
+ }
+ }
+ return 0;
+}
+
+int WebRtcSpl_ComplexIFFT(int16_t frfi[], int stages, int mode)
+{
+ size_t i, j, l, istep, n, m;
+ int k, scale, shift;
+ int16_t wr, wi;
+ int32_t tr32, ti32, qr32, qi32;
+ int32_t tmp32, round2;
+
+ /* The 1024-value is a constant given from the size of kSinTable1024[],
+ * and should not be changed depending on the input parameter 'stages'
+ */
+ n = 1 << stages;
+ if (n > 1024)
+ return -1;
+
+ scale = 0;
+
+ l = 1;
+ k = 10 - 1; /* Constant for given kSinTable1024[]. Do not change
+ depending on the input parameter 'stages' */
+
+ while (l < n)
+ {
+ // variable scaling, depending upon data
+ shift = 0;
+ round2 = 8192;
+
+ tmp32 = WebRtcSpl_MaxAbsValueW16(frfi, 2 * n);
+ if (tmp32 > 13573)
+ {
+ shift++;
+ scale++;
+ round2 <<= 1;
+ }
+ if (tmp32 > 27146)
+ {
+ shift++;
+ scale++;
+ round2 <<= 1;
+ }
+
+ istep = l << 1;
+
+ if (mode == 0)
+ {
+ // mode==0: Low-complexity and Low-accuracy mode
+ for (m = 0; m < l; ++m)
+ {
+ j = m << k;
+
+ /* The 256-value is a constant given as 1/4 of the size of
+ * kSinTable1024[], and should not be changed depending on the input
+ * parameter 'stages'. It will result in 0 <= j < N_SINE_WAVE/2
+ */
+ wr = kSinTable1024[j + 256];
+ wi = kSinTable1024[j];
+
+ for (i = m; i < n; i += istep)
+ {
+ j = i + l;
+
+ tr32 = (wr * frfi[2 * j] - wi * frfi[2 * j + 1]) >> 15;
+
+ ti32 = (wr * frfi[2 * j + 1] + wi * frfi[2 * j]) >> 15;
+
+ qr32 = (int32_t)frfi[2 * i];
+ qi32 = (int32_t)frfi[2 * i + 1];
+ frfi[2 * j] = (int16_t)((qr32 - tr32) >> shift);
+ frfi[2 * j + 1] = (int16_t)((qi32 - ti32) >> shift);
+ frfi[2 * i] = (int16_t)((qr32 + tr32) >> shift);
+ frfi[2 * i + 1] = (int16_t)((qi32 + ti32) >> shift);
+ }
+ }
+ } else
+ {
+ // mode==1: High-complexity and High-accuracy mode
+
+ for (m = 0; m < l; ++m)
+ {
+ j = m << k;
+
+ /* The 256-value is a constant given as 1/4 of the size of
+ * kSinTable1024[], and should not be changed depending on the input
+ * parameter 'stages'. It will result in 0 <= j < N_SINE_WAVE/2
+ */
+ wr = kSinTable1024[j + 256];
+ wi = kSinTable1024[j];
+
+#ifdef WEBRTC_ARCH_ARM_V7
+ int32_t wri = 0;
+ __asm __volatile("pkhbt %0, %1, %2, lsl #16" : "=r"(wri) :
+ "r"((int32_t)wr), "r"((int32_t)wi));
+#endif
+
+ for (i = m; i < n; i += istep)
+ {
+ j = i + l;
+
+#ifdef WEBRTC_ARCH_ARM_V7
+ register int32_t frfi_r;
+ __asm __volatile(
+ "pkhbt %[frfi_r], %[frfi_even], %[frfi_odd], lsl #16\n\t"
+ "smlsd %[tr32], %[wri], %[frfi_r], %[cifftrnd]\n\t"
+ "smladx %[ti32], %[wri], %[frfi_r], %[cifftrnd]\n\t"
+ :[frfi_r]"=&r"(frfi_r),
+ [tr32]"=&r"(tr32),
+ [ti32]"=r"(ti32)
+ :[frfi_even]"r"((int32_t)frfi[2*j]),
+ [frfi_odd]"r"((int32_t)frfi[2*j +1]),
+ [wri]"r"(wri),
+ [cifftrnd]"r"(CIFFTRND)
+ );
+#else
+
+ tr32 = wr * frfi[2 * j] - wi * frfi[2 * j + 1] + CIFFTRND;
+
+ ti32 = wr * frfi[2 * j + 1] + wi * frfi[2 * j] + CIFFTRND;
+#endif
+ tr32 >>= 15 - CIFFTSFT;
+ ti32 >>= 15 - CIFFTSFT;
+
+ qr32 = ((int32_t)frfi[2 * i]) << CIFFTSFT;
+ qi32 = ((int32_t)frfi[2 * i + 1]) << CIFFTSFT;
+
+ frfi[2 * j] = (int16_t)(
+ (qr32 - tr32 + round2) >> (shift + CIFFTSFT));
+ frfi[2 * j + 1] = (int16_t)(
+ (qi32 - ti32 + round2) >> (shift + CIFFTSFT));
+ frfi[2 * i] = (int16_t)(
+ (qr32 + tr32 + round2) >> (shift + CIFFTSFT));
+ frfi[2 * i + 1] = (int16_t)(
+ (qi32 + ti32 + round2) >> (shift + CIFFTSFT));
+ }
+ }
+
+ }
+ --k;
+ l = istep;
+ }
+ return scale;
+}
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