1 files changed, 111 insertions, 0 deletions

diff --git a/lib/rbcodec/codecs/libatrac/fixp_math.h b/lib/rbcodec/codecs/libatrac/fixp_math.h
new file mode 100644
index 0000000000..014c5aa559
--- /dev/null
+++ b/lib/rbcodec/codecs/libatrac/fixp_math.h
@@ -0,0 +1,111 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2009 Mohamed Tarek
+ *
+ * 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#include <stdlib.h>
+#include <inttypes.h>
+
+/* Macros for converting between various fixed-point representations and floating point. */
+#define ONE_16 (1L << 16)
+#define fixtof64(x)       (float)((float)(x) / (float)(1 << 16))        //does not work on int64_t!
+#define ftofix32(x)       ((int32_t)((x) * (float)(1 << 16) + ((x) < 0 ? -0.5 : 0.5)))
+#define ftofix31(x)       ((int32_t)((x) * (float)(1 << 31) + ((x) < 0 ? -0.5 : 0.5)))
+#define fix31tof64(x)     (float)((float)(x) / (float)(1 << 31))
+
+/* Fixed point math routines for use in atrac3.c */
+
+#if defined(CPU_ARM)
+    /* Calculates: result = (X*Y)>>16 */
+    #define fixmul16(X,Y) \
+     ({ \
+        int32_t lo; \
+        int32_t hi; \
+        asm volatile ( \
+           "smull %[lo], %[hi], %[x], %[y] \n\t" /* multiply */ \
+           "mov   %[lo], %[lo], lsr #16    \n\t" /* lo >>= 16 */ \
+           "orr   %[lo], %[lo], %[hi], lsl #16"  /* lo |= (hi << 16) */ \
+           : [lo]"=&r"(lo), [hi]"=&r"(hi) \
+           : [x]"r"(X), [y]"r"(Y)); \
+        lo; \
+     })
+     
+    /* Calculates: result = (X*Y)>>31 */
+    /* Use scratch register r12 */
+    #define fixmul31(X,Y) \
+     ({ \
+        int32_t lo; \
+        int32_t hi; \
+        asm volatile ( \
+           "smull %[lo], %[hi], %[x], %[y] \n\t" /* multiply */ \
+           "mov   %[lo], %[lo], lsr #31    \n\t" /* lo >>= 31 */ \
+           "orr   %[lo], %[lo], %[hi], lsl #1"   /* lo |= (hi << 1) */ \
+           : [lo]"=&r"(lo), [hi]"=&r"(hi) \
+           : [x]"r"(X), [y]"r"(Y)); \
+        lo; \
+     })
+#elif defined(CPU_COLDFIRE)
+    /* Calculates: result = (X*Y)>>16 */
+    #define fixmul16(X,Y) \
+    ({ \
+        int32_t t, x = (X); \
+        asm volatile ( \
+            "mac.l    %[x],%[y],%%acc0\n\t" /* multiply */ \
+            "mulu.l   %[y],%[x]       \n\t" /* get lower half, avoid emac stall */ \
+            "movclr.l %%acc0,%[t]     \n\t" /* get higher half */ \
+            "lsr.l    #1,%[t]         \n\t" /* hi >>= 1 to compensate emac shift */ \
+            "move.w   %[t],%[x]       \n\t" /* combine halfwords */\
+            "swap     %[x]            \n\t" \
+            : [t]"=&d"(t), [x] "+d" (x) \
+            : [y] "d" ((Y))); \
+        x; \
+    })
+
+    #define fixmul31(X,Y) \
+    ({ \
+       int32_t t; \
+       asm volatile ( \
+          "mac.l %[x], %[y], %%acc0\n\t"   /* multiply */ \
+          "movclr.l %%acc0, %[t]\n\t"      /* get higher half as result */ \
+          : [t] "=d" (t) \
+          : [x] "r" ((X)), [y] "r" ((Y))); \
+       t; \
+    })
+#else
+    static inline int32_t fixmul16(int32_t x, int32_t y)
+    {
+        int64_t temp;
+        temp = x;
+        temp *= y;
+    
+        temp >>= 16;
+    
+        return (int32_t)temp;
+    }
+    
+    static inline int32_t fixmul31(int32_t x, int32_t y)
+    {
+        int64_t temp;
+        temp = x;
+        temp *= y;
+    
+        temp >>= 31;        //16+31-16 = 31 bits
+    
+        return (int32_t)temp;
+    }
+#endif