add new denormal handling capabilities (95% finished)

git-svn-id: svn://localhost/ardour2/branches/2.0-ongoing@1935 d708f5d6-7413-0410-9779-e7cbd77b26cf

7 files changed, 119 insertions, 4 deletions

diff --git a/libs/ardour/ardour/ardour.h b/libs/ardour/ardour/ardour.h
index 09c6bd8856..dbc08fff7c 100644
--- a/libs/ardour/ardour/ardour.h
+++ b/libs/ardour/ardour/ardour.h
@@ -75,6 +75,8 @@ namespace ARDOUR {
 	};
 
 	static const double SHUTTLE_FRACT_SPEED1=0.48412291827; /* derived from A1,A2 */
+
+	void setup_fpu ();
 }
 
 /* how do we make these be within the Ardour namespace? */
diff --git a/libs/ardour/ardour/configuration_vars.h b/libs/ardour/ardour/configuration_vars.h
index 07e395c396..8003dc4a4c 100644
--- a/libs/ardour/ardour/configuration_vars.h
+++ b/libs/ardour/ardour/configuration_vars.h
@@ -140,6 +140,11 @@ CONFIG_VARIABLE (bool, use_overlap_equivalency, "use-overlap-equivalency", false
 CONFIG_VARIABLE (bool, periodic_safety_backups, "periodic-safety-backups", true)
 CONFIG_VARIABLE (uint32_t, periodic_safety_backup_interval, "periodic-safety-backup-interval", 120)
 
+/* denormal management */
+
+CONFIG_VARIABLE (bool, denormal_protection, "denormal-protection", false)
+CONFIG_VARIABLE (DenormalModel, denormal_model, "denormal-model", DenormalNone)
+
 /* BWAV */
 
 CONFIG_VARIABLE (string, bwf_country_code, "bwf-country-code", "US")
diff --git a/libs/ardour/ardour/route.h b/libs/ardour/ardour/route.h
index 9bdd2cbca5..8f3cae0db1 100644
--- a/libs/ardour/ardour/route.h
+++ b/libs/ardour/ardour/route.h
@@ -127,6 +127,10 @@ class Route : public IO
 
 	void set_phase_invert (bool yn, void *src);
 	bool phase_invert() const { return _phase_invert; }
+
+	void set_denormal_protection (bool yn, void *src);
+	bool denormal_protection() const { return _denormal_protection; }
+
 	
 	void       set_edit_group (RouteGroup *, void *);
 	void       drop_edit_group (void *);
@@ -258,6 +262,7 @@ class Route : public IO
 	bool                     _soloed : 1;
 	bool                     _solo_safe : 1;
 	bool                     _phase_invert : 1;
+	bool                     _denormal_protection : 1;
 	bool                     _recordable : 1;
 	bool                     _active : 1;
 	bool                     _mute_affects_pre_fader : 1;
diff --git a/libs/ardour/ardour/types.h b/libs/ardour/ardour/types.h
index 7655f486e9..182172dff6 100644
--- a/libs/ardour/ardour/types.h
+++ b/libs/ardour/ardour/types.h
@@ -272,6 +272,13 @@ namespace ARDOUR {
 		ExternalMonitoring,
 	};
 
+	enum DenormalModel {
+		DenormalNone,
+		DenormalFTZ,
+		DenormalDAZ,
+		DenormalFTZDAZ
+	};
+
 	enum RemoteModel {
 		UserOrdered,
 		MixerOrdered,
@@ -368,6 +375,7 @@ std::istream& operator>>(std::istream& o, ARDOUR::SlaveSource& sf);
 std::istream& operator>>(std::istream& o, ARDOUR::ShuttleBehaviour& sf);
 std::istream& operator>>(std::istream& o, ARDOUR::ShuttleUnits& sf);
 std::istream& operator>>(std::istream& o, ARDOUR::SmpteFormat& sf);
+std::istream& operator>>(std::istream& o, ARDOUR::DenormalModel& sf);
 
 static inline nframes_t
 session_frame_to_track_frame (nframes_t session_frame, double speed)
diff --git a/libs/ardour/enums.cc b/libs/ardour/enums.cc
index 345fbe771d..5a4ee251b6 100644
--- a/libs/ardour/enums.cc
+++ b/libs/ardour/enums.cc
@@ -51,6 +51,7 @@ setup_enum_writer ()
 	Placement _Placement;
 	MonitorModel _MonitorModel;
 	RemoteModel _RemoteModel;
+	DenormalModel _DenormalModel;
 	CrossfadeModel _CrossfadeModel;
 	LayerModel _LayerModel;
 	SoloModel _SoloModel;
@@ -162,6 +163,12 @@ setup_enum_writer ()
 	REGISTER_ENUM (ExternalMonitoring);
 	REGISTER (_MonitorModel);
 
+	REGISTER_ENUM (DenormalNone);
+	REGISTER_ENUM (DenormalFTZ);
+	REGISTER_ENUM (DenormalDAZ);
+	REGISTER_ENUM (DenormalFTZDAZ);
+	REGISTER (_DenormalModel);
+
 	REGISTER_ENUM (UserOrdered);
 	REGISTER_ENUM (MixerOrdered);
 	REGISTER_ENUM (EditorOrdered);
diff --git a/libs/ardour/globals.cc b/libs/ardour/globals.cc
index 2d22f4eb11..eb5a2cc9f2 100644
--- a/libs/ardour/globals.cc
+++ b/libs/ardour/globals.cc
@@ -28,6 +28,10 @@
 #include <fst.h>
 #endif
 
+#ifdef __SSE__
+#include <xmmintrin.h>
+#endif
+
 #include <lrdf.h>
 
 #include <pbd/error.h>
@@ -228,8 +232,9 @@ setup_hardware_optimization (bool try_optimization)
 			 : "%rax", "%rcx", "%rdx", "memory");
 
 #endif /* USE_X86_64_ASM */
+
 		use_sse &= (1 << 25); // bit 25 = SSE support
-		
+
 		if (use_sse) {
 			info << "Using SSE optimized routines" << endmsg;
 	
@@ -274,6 +279,9 @@ setup_hardware_optimization (bool try_optimization)
 		
 		info << "No H/W specific optimizations in use" << endmsg;
 	}
+
+	setup_fpu ();
+
 }
 
 int
@@ -527,6 +535,55 @@ ARDOUR::LocaleGuard::~LocaleGuard ()
 	free ((char*)old);
 }
 
+void
+ARDOUR::setup_fpu ()
+{
+#ifdef USE_XMMINTRIN
+	int MXCSR;
+
+	/* XXX use real code to determine if the processor supports
+	   DenormalsAreZero and FlushToZero
+	*/
+	
+	bool has_daz = false;
+	bool can_ftz = true;
+
+	if (!can_ftz && !has_daz) {
+		return;
+	}
+
+	MXCSR  = _mm_getcsr();
+
+	switch (Config->get_denormal_model()) {
+	case DenormalNone:
+		MXCSR &= ~_MM_FLUSH_ZERO_ON;
+		break;
+
+	case DenormalFTZ:
+		MXCSR |= _MM_FLUSH_ZERO_ON;
+		break;
+
+	case DenormalDAZ:
+		MXCSR &= ~_MM_FLUSH_ZERO_ON;
+		if (has_daz) {
+			MXCSR |= 0x8000;
+		}
+		break;
+		
+	case DenormalFTZDAZ:
+		if (has_daz) {
+			MXCSR |= _MM_FLUSH_ZERO_ON | 0x8000;
+		} else {
+			MXCSR |= _MM_FLUSH_ZERO_ON;
+		}
+		break;
+	}
+
+	_mm_setcsr (MXCSR);
+
+#endif
+}
+
 ARDOUR::OverlapType
 ARDOUR::coverage (nframes_t sa, nframes_t ea, 
 		  nframes_t sb, nframes_t eb)
@@ -629,4 +686,5 @@ std::istream& operator>>(std::istream& o, SlaveSource& var) { return int_to_type
 std::istream& operator>>(std::istream& o, ShuttleBehaviour& var) { return int_to_type<ShuttleBehaviour> (o, var); }
 std::istream& operator>>(std::istream& o, ShuttleUnits& var) { return int_to_type<ShuttleUnits> (o, var); }
 std::istream& operator>>(std::istream& o, SmpteFormat& var) { return int_to_type<SmpteFormat> (o, var); }
+std::istream& operator>>(std::istream& o, DenormalModel& var) { return int_to_type<DenormalModel> (o, var); }
 
diff --git a/libs/ardour/route.cc b/libs/ardour/route.cc
index 3f9fa2737f..11132984f0 100644
--- a/libs/ardour/route.cc
+++ b/libs/ardour/route.cc
@@ -48,7 +48,6 @@ using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
-
 uint32_t Route::order_key_cnt = 0;
 
 
@@ -78,6 +77,7 @@ Route::init ()
 	_soloed = false;
 	_solo_safe = false;
 	_phase_invert = false;
+	_denormal_protection = false;
 	order_keys[strdup (N_("signal"))] = order_key_cnt++;
 	_active = true;
 	_silent = false;
@@ -341,6 +341,22 @@ Route::process_output_buffers (vector<Sample*>& bufs, uint32_t nbufs,
 		} 
 	} 
 
+	/* -----------------------------------------------------------------------------------------------------
+	   DENORMAL CONTROL
+	   -------------------------------------------------------------------------------------------------- */
+
+	if (_denormal_protection || Config->get_denormal_protection()) {
+
+		for (n = 0; n < nbufs; ++n)  {
+			Sample *sp = bufs[n];
+			
+			for (nframes_t nx = offset; nx < nframes + offset; ++nx) {
+				sp[nx] += 1.0e-27f;
+			}
+		}
+	}
+
+
 	/* ----------------------------------------------------------------------------------------------------
 	   PRE-FADER REDIRECTS
 	   -------------------------------------------------------------------------------------------------- */
@@ -724,8 +740,17 @@ Route::set_phase_invert (bool yn, void *src)
 {
 	if (_phase_invert != yn) {
 		_phase_invert = yn;
+		//  phase_invert_changed (src); /* EMIT SIGNAL */
+	}
+}
+
+void
+Route::set_denormal_protection (bool yn, void *src)
+{
+	if (_denormal_protection != yn) {
+		_denormal_protection = yn;
+		//  denormal_protection_changed (src); /* EMIT SIGNAL */
 	}
-	//  phase_invert_changed (src); /* EMIT SIGNAL */
 }
 
 void
@@ -1404,6 +1429,7 @@ Route::state(bool full_state)
 	node->add_property("muted", _muted?"yes":"no");
 	node->add_property("soloed", _soloed?"yes":"no");
 	node->add_property("phase-invert", _phase_invert?"yes":"no");
+	node->add_property("denormal-protection", _denormal_protection?"yes":"no");
 	node->add_property("mute-affects-pre-fader", _mute_affects_pre_fader?"yes":"no"); 
 	node->add_property("mute-affects-post-fader", _mute_affects_post_fader?"yes":"no"); 
 	node->add_property("mute-affects-control-outs", _mute_affects_control_outs?"yes":"no"); 
@@ -1571,7 +1597,11 @@ Route::_set_state (const XMLNode& node, bool call_base)
 	}
 
 	if ((prop = node.property (X_("phase-invert"))) != 0) {
-		set_phase_invert(prop->value()=="yes"?true:false, this);
+		set_phase_invert (prop->value()=="yes"?true:false, this);
+	}
+
+	if ((prop = node.property (X_("denormal-protection"))) != 0) {
+		set_denormal_protection (prop->value()=="yes"?true:false, this);
 	}
 
 	if ((prop = node.property (X_("active"))) != 0) {