DSP: Added missing snapToZero in the StateVariableFilter

modules/juce_dsp/containers/juce_SIMDRegister.h

@@ -386,6 +386,14 @@ struct CmplxSIMDOps<std::complex<Scalar> >
     }
 };
 
+//==============================================================================
+#ifndef DOXYGEN
+ namespace util
+ {
+     template <typename Type>
+     inline void snapToZero (SIMDRegister<Type>&) noexcept      {}
+ }
+#endif
 
 //==============================================================================
 // Extend some common used global functions to SIMDRegister types

modules/juce_dsp/juce_dsp.h

@@ -177,6 +177,21 @@ namespace juce
         template <typename Type>
         using Complex = ::std::complex<Type>;
 
+        //==============================================================================
+        namespace util
+        {
+            /** Use this function to prevent denormals on intel CPUs.
+
+                This function will work with both primitives and simple containers.
+            */
+            inline void snapToZero (float&       x) noexcept            { JUCE_SNAP_TO_ZERO (x); }
+           #ifndef DOXYGEN
+            inline void snapToZero (double&      x) noexcept            { JUCE_SNAP_TO_ZERO (x); }
+            inline void snapToZero (long double& x) noexcept            { JUCE_SNAP_TO_ZERO (x); }
+           #endif
+        }
+
+        //==============================================================================
        #if JUCE_USE_SIMD
         #include "native/juce_fallback_SIMDNativeOps.h"
 

modules/juce_dsp/processors/juce_IIRFilter_Impl.h

@@ -26,25 +26,6 @@
 
 #ifndef DOXYGEN
 
-template <typename Type>
-struct SnapToZeroHelper
-{
-    static void snap (Type& x) noexcept
-    {
-        for (size_t i = 0; i < Type::size(); ++i)
-            JUCE_SNAP_TO_ZERO (x[i]);
-    }
-};
-
-template <> struct SnapToZeroHelper<float>       { static void snap (float& x)       noexcept { JUCE_SNAP_TO_ZERO (x); } };
-template <> struct SnapToZeroHelper<double>      { static void snap (double& x)      noexcept { JUCE_SNAP_TO_ZERO (x); } };
-template <> struct SnapToZeroHelper<long double> { static void snap (long double& x) noexcept { JUCE_SNAP_TO_ZERO (x); } };
-
-#if JUCE_USE_SIMD
-template <typename Type>
-struct SnapToZeroHelper<SIMDRegister<Type>>      { static void snap (SIMDRegister<Type>&) noexcept {} };
-#endif
-
 //==============================================================================
 template <typename SampleType>
 Filter<SampleType>::Filter()
@@ -120,7 +101,7 @@ void Filter<SampleType>::process (const ProcessContext& context) noexcept
                 lv1 = (in * b1) - (out * a1);
             }
 
-            SnapToZeroHelper<SampleType>::snap (lv1); state[0] = lv1;
+            util::snapToZero (lv1); state[0] = lv1;
         }
         break;
 
@@ -145,8 +126,8 @@ void Filter<SampleType>::process (const ProcessContext& context) noexcept
                 lv2 = (in * b2) - (out * a2);
             }
 
-            SnapToZeroHelper<SampleType>::snap (lv1); state[0] = lv1;
-            SnapToZeroHelper<SampleType>::snap (lv2); state[1] = lv2;
+            util::snapToZero (lv1); state[0] = lv1;
+            util::snapToZero (lv2); state[1] = lv2;
         }
         break;
 
@@ -175,9 +156,9 @@ void Filter<SampleType>::process (const ProcessContext& context) noexcept
                 lv3 = (in * b3) - (out * a3);
             }
 
-            SnapToZeroHelper<SampleType>::snap (lv1); state[0] = lv1;
-            SnapToZeroHelper<SampleType>::snap (lv2); state[1] = lv2;
-            SnapToZeroHelper<SampleType>::snap (lv3); state[2] = lv3;
+            util::snapToZero (lv1); state[0] = lv1;
+            util::snapToZero (lv2); state[1] = lv2;
+            util::snapToZero (lv3); state[2] = lv3;
         }
         break;
 
@@ -220,7 +201,7 @@ template <typename SampleType>
 void Filter<SampleType>::snapToZero() noexcept
 {
     for (size_t i = 0; i < order; ++i)
-        SnapToZeroHelper<SampleType>::snap (state[i]);
+        util::snapToZero (state[i]);
 }
 
 template <typename SampleType>

modules/juce_dsp/processors/juce_StateVariableFilter.h

@@ -141,6 +141,9 @@ namespace StateVariableFilter
             for (size_t i = 0 ; i < n; ++i)
                 output[i] = processLoop<type> (input[i], state);
 
+            util::snapToZero (s1);
+            util::snapToZero (s2);
+
             *parameters = state;
         }