slight optimization of float_to_int casts in streamer

5 files changed, 169 insertions, 2 deletions

diff --git a/Makefile.am b/Makefile.am
index 54f21ecd..eb25a581 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -36,7 +36,7 @@ sdk_HEADERS = deadbeef.h
 
 deadbeef_LDADD = $(LDADD) $(DEPS_LIBS) gme/Game_Music_Emu-0.5.2/gme/libgme.a sid/sidplay-libs-2.1.0/libsidplay2.a dumb/libdumb.a
 
-AM_CFLAGS = $(DEPS_CFLAGS) -I$(gmepath) -std=c99
+AM_CFLAGS = $(DEPS_CFLAGS) -I$(gmepath) -std=c99 -msse2
 AM_CPPFLAGS = $(DEPS_CFLAGS) -I$(sidpath)/libsidplay/include -I$(sidpath)/builders/resid-builder/include
 
 docsdir = $(datadir)/doc/$(PACKAGE)
diff --git a/optmath.h b/optmath.h
new file mode 100644
index 00000000..54271cee
--- /dev/null
+++ b/optmath.h
@@ -0,0 +1,130 @@
+/*
+    DeaDBeeF - ultimate music player for GNU/Linux systems with X11
+    Copyright (C) 2009  Alexey Yakovenko
+
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License
+    as published by the Free Software Foundation; either version 2
+    of the License, or (at your option) any later version.
+    
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+    
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+#ifndef __OPTMATH_H
+#define __OPTMATH_H
+
+#define __FORCE_SSE2__
+// some maths
+// taken from vorbis/lib/os.h, (C) 1994-2007 Xiph.Org Foundation http://www.xiph.org/
+
+/* Special i386 GCC implementation */
+#if defined(__i386__) && defined(__GNUC__) && !defined(__BEOS__) && !defined(__FORCE_SSE2__)
+#  define FPU_CONTROL
+/* both GCC and MSVC are kinda stupid about rounding/casting to int.
+   Because of encapsulation constraints (GCC can't see inside the asm
+   block and so we end up doing stupid things like a store/load that
+   is collectively a noop), we do it this way */
+
+/* we must set up the fpu before this works!! */
+
+typedef int16_t fpu_control;
+
+static inline void fpu_setround(fpu_control *fpu){
+  int16_t ret;
+  int16_t temp;
+  __asm__ __volatile__("fnstcw %0\n\t"
+	  "movw %0,%%dx\n\t"
+	  "orw $62463,%%dx\n\t"
+	  "movw %%dx,%1\n\t"
+	  "fldcw %1\n\t":"=m"(ret):"m"(temp): "dx");
+  *fpu=ret;
+}
+
+static inline void fpu_restore(fpu_control fpu){
+  __asm__ __volatile__("fldcw %0":: "m"(fpu));
+}
+
+/* assumes the FPU is in round mode! */
+static inline int ftoi(double f){  /* yes, double!  Otherwise,
+                                             we get extra fst/fld to
+                                             truncate precision */
+  int i;
+  __asm__("fistl %0": "=m"(i) : "t"(f));
+  return(i);
+}
+#endif /* Special i386 GCC implementation */
+
+
+/* MSVC inline assembly. 32 bit only; inline ASM isn't implemented in the
+ * 64 bit compiler */
+#if defined(_MSC_VER) && !defined(_WIN64)
+#  define FPU_CONTROL
+
+typedef int16_t fpu_control;
+
+static __inline int ftoi(double f){
+	int i;
+	__asm{
+		fld f
+		fistp i
+	}
+	return i;
+}
+
+static __inline void fpu_setround(fpu_control *fpu){
+}
+
+static __inline void fpu_restore(fpu_control fpu){
+}
+
+#endif /* Special MSVC 32 bit implementation */
+
+
+/* Optimized code path for x86_64 builds. Uses SSE2 intrinsics. This can be
+   done safely because all x86_64 CPUs supports SSE2. */
+#if (defined(__FORCE_SSE2__)) || (defined(_MSC_VER) && defined(_WIN64)) || (defined(__GNUC__) && defined (__x86_64__))
+#pragma warning using sse2 for ftoi
+#  define FPU_CONTROL
+
+typedef int16_t fpu_control;
+
+#include <emmintrin.h>
+static __inline int ftoi(double f){
+        return _mm_cvtsd_si32(_mm_load_sd(&f));
+}
+
+static __inline void fpu_setround(fpu_control *fpu){
+}
+
+static __inline void fpu_restore(fpu_control fpu){
+}
+
+#endif /* Special MSVC x64 implementation */
+
+
+/* If no special implementation was found for the current compiler / platform,
+   use the default implementation here: */
+#ifndef FPU_CONTROL
+
+typedef int fpu_control;
+
+static int ftoi(double f){
+        /* Note: MSVC and GCC (at least on some systems) round towards zero, thus,
+           the floor() call is required to ensure correct roudning of
+           negative numbers */
+        return (int)floor(f+.5);
+}
+
+/* We don't have special code for this compiler/arch, so do it the slow way */
+#  define fpu_setround(fpu_control) {}
+#  define fpu_restore(fpu_control) {}
+
+#endif /* default implementation */
+
+#endif // __OPTMATH_H
diff --git a/plugins.c b/plugins.c
index 60c36a8e..e0261d00 100644
--- a/plugins.c
+++ b/plugins.c
@@ -1,3 +1,21 @@
+/*
+    DeaDBeeF - ultimate music player for GNU/Linux systems with X11
+    Copyright (C) 2009  Alexey Yakovenko
+
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License
+    as published by the Free Software Foundation; either version 2
+    of the License, or (at your option) any later version.
+    
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+    
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
 #include <dirent.h>
 #include <dlfcn.h>
 #include <assert.h>
diff --git a/plugins.h b/plugins.h
index a82a2eb7..8924ac42 100644
--- a/plugins.h
+++ b/plugins.h
@@ -1,3 +1,21 @@
+/*
+    DeaDBeeF - ultimate music player for GNU/Linux systems with X11
+    Copyright (C) 2009  Alexey Yakovenko
+
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License
+    as published by the Free Software Foundation; either version 2
+    of the License, or (at your option) any later version.
+    
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+    
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
 #ifndef __PLUGINS_H
 #define __PLUGINS_H
 #include "deadbeef.h"
diff --git a/streamer.c b/streamer.c
index 91ae3cda..fd60922f 100644
--- a/streamer.c
+++ b/streamer.c
@@ -32,6 +32,7 @@
 #include "messages.h"
 #include "conf.h"
 #include "plugins.h"
+#include "optmath.h"
 
 static int streamer_tid;
 static SRC_STATE *src;
@@ -320,7 +321,7 @@ streamer_read_async (char *bytes, int size) {
                     if (sample < -1) {
                         sample = -1;
                     }
-                    ((int16_t*)bytes)[i] = (int16_t)(sample*32767.f);
+                    ((int16_t*)bytes)[i] = (int16_t)ftoi (sample*32767.f);
                 }
                 // calculate how many unused input samples left
                 codecleft = nsamples - srcdata.input_frames_used;