Merge pull request #2018 from softrabbit/denormal_refactor

Denormal protection refactoring

include/Mixer.h

@@ -25,13 +25,7 @@
 #ifndef MIXER_H
 #define MIXER_H
 
-// denormals stripping
-#ifdef __SSE__
-#include <xmmintrin.h>
-#endif
-#ifdef __SSE3__
-#include <pmmintrin.h>
-#endif
+#include "denormals.h"
 
 #include "lmmsconfig.h"
 

include/denormals.h

@@ -0,0 +1,32 @@
+// Denormals stripping. 
+// These snippets should be common enough to be considered public domain.
+
+#ifndef DENORMALS_H
+#define DENORMALS_H
+
+
+#ifdef __SSE__
+#include <xmmintrin.h>
+#endif
+#ifdef __SSE3__
+#include <pmmintrin.h>
+#endif
+
+
+// Set denormal protection for this thread. 
+// To be on the safe side, don't set the DAZ flag for SSE2 builds, 
+// even if most SSE2 CPUs can handle it. 
+void inline disable_denormals() {
+#ifdef __SSE3__
+	/* DAZ flag */
+	_MM_SET_DENORMALS_ZERO_MODE( _MM_DENORMALS_ZERO_ON );
+#endif
+
+#ifdef __SSE__
+	/* FTZ flag */
+	_MM_SET_FLUSH_ZERO_MODE( _MM_FLUSH_ZERO_ON );
+#endif
+}
+
+#endif
+