FFT cache disable support. Move czt from fft module.

Author: vitalsong

CMakeLists.txt

@@ -43,13 +43,13 @@ set(DSPLIB_SOURCES
     lib/resample/resample.cpp
     lib/fft.cpp
     lib/ifft.cpp
+    lib/czt.cpp
 )
 
 if (DSPLIB_EXCLUDE_FFT)
     message(STATUS "dsplib: use custom fft implementation")
 else()
     list(APPEND DSPLIB_SOURCES
-        lib/fft/czt.cpp
         lib/fft/fact-fft.cpp
         lib/fft/factory.cpp
         lib/fft/pow2-fft.cpp

include/dsplib/czt.h

@@ -7,7 +7,7 @@ namespace dsplib {
 
 class CztPlanImpl;
 
-class CztPlan : public BaseFftPlanC
+class CztPlan : public FftPlanC
 {
 public:
     explicit CztPlan(int n, int m, cmplx_t w, cmplx_t a = 1);

lib/fft/czt.cpp lib/czt.cpplib/fft/czt.cpp renamed to lib/czt.cpp

@@ -21,7 +21,7 @@ namespace {
 
 constexpr int FFT_CACHE_SIZE = DSPLIB_FFT_CACHE_SIZE;
 
-static_assert(FFT_CACHE_SIZE > 0);
+static_assert(FFT_CACHE_SIZE >= 0);
 
 //TODO: common plan for complex fft/ifft
 
@@ -62,48 +62,64 @@ std::shared_ptr<FftPlanC> fft_plan_c(int n) {
         return std::make_shared<SmallFftC>(n);
     }
 
-    //TODO: use weak_ptr cache to prevent duplication
-    thread_local LRUCache<int, std::shared_ptr<FftPlanC>> cache{FFT_CACHE_SIZE};
-    if (!cache.exists(n)) {
-        auto plan = _get_fft_plan(n);
-        cache.put(n, plan);
-        return plan;
+    if constexpr (FFT_CACHE_SIZE > 0) {
+        //TODO: use weak_ptr cache to prevent duplication
+        thread_local LRUCache<int, std::shared_ptr<FftPlanC>> cache{FFT_CACHE_SIZE};
+        if (!cache.exists(n)) {
+            auto plan = _get_fft_plan(n);
+            cache.put(n, plan);
+            return plan;
+        }
+        return cache.get(n);
+    } else {
+        return _get_fft_plan(n);
     }
-    return cache.get(n);
 }
 
 std::shared_ptr<FftPlanR> fft_plan_r(int n) {
     if (SmallFftR::is_supported(n)) {
         return std::make_shared<SmallFftR>(n);
     }
 
-    thread_local LRUCache<int, std::shared_ptr<FftPlanR>> cache{FFT_CACHE_SIZE};
-    if (!cache.exists(n)) {
-        auto plan = _get_rfft_plan(n);
-        cache.put(n, plan);
-        return plan;
+    if constexpr (FFT_CACHE_SIZE > 0) {
+        thread_local LRUCache<int, std::shared_ptr<FftPlanR>> cache{FFT_CACHE_SIZE};
+        if (!cache.exists(n)) {
+            auto plan = _get_rfft_plan(n);
+            cache.put(n, plan);
+            return plan;
+        }
+        return cache.get(n);
+    } else {
+        return _get_rfft_plan(n);
     }
-    return cache.get(n);
 }
 
 std::shared_ptr<IfftPlanC> ifft_plan_c(int n) {
-    thread_local LRUCache<int, std::shared_ptr<IfftPlanC>> cache{FFT_CACHE_SIZE};
-    if (!cache.exists(n)) {
-        auto plan = _get_ifft_plan(n);
-        cache.put(n, plan);
-        return plan;
+    if constexpr (FFT_CACHE_SIZE > 0) {
+        thread_local LRUCache<int, std::shared_ptr<IfftPlanC>> cache{FFT_CACHE_SIZE};
+        if (!cache.exists(n)) {
+            auto plan = _get_ifft_plan(n);
+            cache.put(n, plan);
+            return plan;
+        }
+        return cache.get(n);
+    } else {
+        return _get_ifft_plan(n);
     }
-    return cache.get(n);
 }
 
 std::shared_ptr<IfftPlanR> ifft_plan_r(int n) {
-    thread_local LRUCache<int, std::shared_ptr<IfftPlanR>> cache{FFT_CACHE_SIZE};
-    if (!cache.exists(n)) {
-        auto plan = _get_irfft_plan(n);
-        cache.put(n, plan);
-        return plan;
+    if constexpr (FFT_CACHE_SIZE > 0) {
+        thread_local LRUCache<int, std::shared_ptr<IfftPlanR>> cache{FFT_CACHE_SIZE};
+        if (!cache.exists(n)) {
+            auto plan = _get_irfft_plan(n);
+            cache.put(n, plan);
+            return plan;
+        }
+        return cache.get(n);
+    } else {
+        return _get_irfft_plan(n);
     }
-    return cache.get(n);
 }
 
 }   // namespace dsplib