libavutil: Utility code from libavcodec moved to a separate library.

Originally committed as revision 4489 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 155 insertions, 0 deletions

diff --git a/libavutil/bswap.h b/libavutil/bswap.h
new file mode 100644
index 0000000000..50fd571787
--- /dev/null
+++ b/libavutil/bswap.h
@@ -0,0 +1,155 @@
+/**
+ * @file bswap.h
+ * byte swap.
+ */
+
+#ifndef __BSWAP_H__
+#define __BSWAP_H__
+
+#ifdef HAVE_BYTESWAP_H
+#include <byteswap.h>
+#else
+
+#ifdef ARCH_X86_64
+#  define LEGACY_REGS "=Q"
+#else
+#  define LEGACY_REGS "=q"
+#endif
+
+#if defined(ARCH_X86) || defined(ARCH_X86_64)
+static always_inline uint16_t bswap_16(uint16_t x)
+{
+  __asm("rorw $8, %0"	:
+        LEGACY_REGS (x)	:
+        "0" (x));
+    return x;
+}
+
+static always_inline uint32_t bswap_32(uint32_t x)
+{
+#if __CPU__ > 386
+ __asm("bswap	%0":
+      "=r" (x)     :
+#else
+ __asm("xchgb	%b0,%h0\n"
+      "	rorl	$16,%0\n"
+      "	xchgb	%b0,%h0":
+      LEGACY_REGS (x)		:
+#endif
+      "0" (x));
+  return x;
+}
+
+static inline uint64_t bswap_64(uint64_t x)
+{
+#ifdef ARCH_X86_64
+  __asm("bswap	%0":
+        "=r" (x)     :
+        "0" (x));
+  return x;
+#else
+    union { 
+        uint64_t ll;
+        struct {
+           uint32_t l,h;
+        } l;
+    } r;
+    r.l.l = bswap_32 (x);
+    r.l.h = bswap_32 (x>>32);
+    return r.ll;
+#endif
+}
+
+#elif defined(ARCH_SH4)
+
+static always_inline uint16_t bswap_16(uint16_t x) {
+	__asm__("swap.b %0,%0":"=r"(x):"0"(x));
+	return x;
+}
+
+static always_inline uint32_t bswap_32(uint32_t x) {
+	__asm__(
+	"swap.b %0,%0\n"
+	"swap.w %0,%0\n"
+	"swap.b %0,%0\n"
+	:"=r"(x):"0"(x));
+	return x;
+}
+
+static inline uint64_t bswap_64(uint64_t x)
+{
+    union { 
+        uint64_t ll;
+        struct {
+           uint32_t l,h;
+        } l;
+    } r;
+    r.l.l = bswap_32 (x);
+    r.l.h = bswap_32 (x>>32);
+    return r.ll;
+}
+#else
+
+static always_inline uint16_t bswap_16(uint16_t x){
+    return (x>>8) | (x<<8);
+}
+
+#ifdef ARCH_ARM
+static always_inline uint32_t bswap_32(uint32_t x){
+    uint32_t t;
+    __asm__ (
+      "eor %1, %0, %0, ror #16 \n\t"
+      "bic %1, %1, #0xFF0000   \n\t"
+      "mov %0, %0, ror #8      \n\t"
+      "eor %0, %0, %1, lsr #8  \n\t"
+      : "+r"(x), "+r"(t));
+    return x;
+}
+#else
+static always_inline uint32_t bswap_32(uint32_t x){
+    x= ((x<<8)&0xFF00FF00) | ((x>>8)&0x00FF00FF);
+    return (x>>16) | (x<<16);
+}
+#endif
+
+static inline uint64_t bswap_64(uint64_t x)
+{
+#if 0
+    x= ((x<< 8)&0xFF00FF00FF00FF00ULL) | ((x>> 8)&0x00FF00FF00FF00FFULL);
+    x= ((x<<16)&0xFFFF0000FFFF0000ULL) | ((x>>16)&0x0000FFFF0000FFFFULL);
+    return (x>>32) | (x<<32);
+#else
+    union { 
+        uint64_t ll;
+        uint32_t l[2]; 
+    } w, r;
+    w.ll = x;
+    r.l[0] = bswap_32 (w.l[1]);
+    r.l[1] = bswap_32 (w.l[0]);
+    return r.ll;
+#endif
+}
+#endif	/* !ARCH_X86 */
+
+#endif	/* !HAVE_BYTESWAP_H */
+
+// be2me ... BigEndian to MachineEndian
+// le2me ... LittleEndian to MachineEndian
+
+#ifdef WORDS_BIGENDIAN
+#define be2me_16(x) (x)
+#define be2me_32(x) (x)
+#define be2me_64(x) (x)
+#define le2me_16(x) bswap_16(x)
+#define le2me_32(x) bswap_32(x)
+#define le2me_64(x) bswap_64(x)
+#else
+#define be2me_16(x) bswap_16(x)
+#define be2me_32(x) bswap_32(x)
+#define be2me_64(x) bswap_64(x)
+#define le2me_16(x) (x)
+#define le2me_32(x) (x)
+#define le2me_64(x) (x)
+#endif
+
+#endif /* __BSWAP_H__ */