Code clean up: Move fixed point functions into their own files. Move various lookup tables into header files.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@13784 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 92 insertions, 0 deletions

diff --git a/apps/codecs/libwma/wmafixed.h b/apps/codecs/libwma/wmafixed.h
new file mode 100644
index 0000000000..878601d799
--- /dev/null
+++ b/apps/codecs/libwma/wmafixed.h
@@ -0,0 +1,92 @@
+/*      fixed precision code.  We use a combination of Sign 15.16 and Sign.31
+        precision here.
+
+        The WMA decoder does not always follow this convention, and occasionally
+        renormalizes values to other formats in order to maximize precision.
+        However, only the two precisions above are provided in this file.
+
+*/
+
+
+#define PRECISION       16
+#define PRECISION64     16
+
+
+#define fixtof64(x)       (float)((float)(x) / (float)(1 << PRECISION64))        //does not work on int64_t!
+#define ftofix32(x)       ((fixed32)((x) * (float)(1 << PRECISION) + ((x) < 0 ? -0.5 : 0.5)))
+#define itofix64(x)       (IntTo64(x))
+#define itofix32(x)       ((x) << PRECISION)
+#define fixtoi32(x)       ((x) >> PRECISION)
+#define fixtoi64(x)       (IntFrom64(x))
+
+
+/*fixed functions*/
+
+fixed64 IntTo64(int x);
+int IntFrom64(fixed64 x);
+fixed32 Fixed32From64(fixed64 x);
+fixed64 Fixed32To64(fixed32 x);
+fixed64 fixmul64byfixed(fixed64 x, fixed32 y);
+fixed32 fixdiv32(fixed32 x, fixed32 y);
+fixed64 fixdiv64(fixed64 x, fixed64 y);
+fixed32 fixsqrt32(fixed32 x);
+fixed32 fixsin32(fixed32 x);
+fixed32 fixcos32(fixed32 x);
+long fsincos(unsigned long phase, fixed32 *cos);
+
+
+
+
+
+#ifdef CPU_ARM
+
+/*
+        Fixed precision multiply code ASM.
+
+*/
+
+/*Sign-15.16 format */
+
+#define fixmul32(x, y)  \
+    ({ int32_t __hi;  \
+       uint32_t __lo;  \
+       int32_t __result;  \
+       asm ("smull   %0, %1, %3, %4\n\t"  \
+            "movs    %0, %0, lsr %5\n\t"  \
+            "adc    %2, %0, %1, lsl %6"  \
+            : "=&r" (__lo), "=&r" (__hi), "=r" (__result)  \
+            : "%r" (x), "r" (y),  \
+              "M" (PRECISION), "M" (32 - PRECISION)  \
+            : "cc");  \
+       __result;  \
+    })
+
+/*
+        Special fixmul32 that does a 16.16 x 1.31 multiply that returns a 16.16 value.
+        this is needed because the fft constants are all normalized to be less then 1
+        and can't fit into a 16 bit number without excessive rounding
+
+
+*/
+
+
+#  define fixmul32b(x, y)  \
+    ({ int32_t __hi;  \
+       uint32_t __lo;  \
+       int32_t __result;  \
+       asm ("smull    %0, %1, %3, %4\n\t"  \
+        "movs    %0, %0, lsr %5\n\t"  \
+        "adc    %2, %0, %1, lsl %6"  \
+        : "=&r" (__lo), "=&r" (__hi), "=r" (__result)  \
+        : "%r" (x), "r" (y),  \
+          "M" (31), "M" (1)  \
+        : "cc");  \
+       __result;  \
+    })
+
+
+#else
+fixed32 fixmul32(fixed32 x, fixed32 y);
+fixed32 fixmul32b(fixed32 x, fixed32 y);
+#endif
+