CPU: byte order helper functions refactoring

Define all the cpu_to_*/*_to_cpu() functions as macro and make use of
__builtin_bswap*() gcc functions when possible.

This allows to use the byteorder helper functions as constant
initializers.

git-svn-id: https://src.develer.com/svnoss/bertos/trunk@4278 38d2e660-2303-0410-9eaa-f027e97ec537

diff --git a/bertos/cpu/byteorder.h b/bertos/cpu/byteorder.h
index d5874a57702872da588499cd5e3c5c59b91b8520..f2d402df20682db906f587786231288015753f36 100644 (file)
--- a/bertos/cpu/byteorder.h
+++ b/bertos/cpu/byteorder.h
@@ -44,31 +44,78 @@
 /**
  * Swap upper and lower bytes in a 16-bit value.
  */
-INLINE uint16_t swab16(uint16_t x)
-{
-       return    ((x & (uint16_t)0x00FFU) << 8)
-               | ((x & (uint16_t)0xFF00U) >> 8);
-}
+#define swab16(x) ((uint16_t)(ROTR(x, 8)))
 
+#if GNUC_PREREQ(4, 3)
+#define SWAB32(x) __builtin_bswap32(x)
+#define SWAB64(x) __builtin_bswap64(x)
+#else
 /**
  * Reverse bytes in a 32-bit value (e.g.: 0x12345678 -> 0x78563412).
  */
-INLINE uint32_t swab32(uint32_t x)
-{
-       return    ((x & (uint32_t)0x000000FFUL) << 24)
-               | ((x & (uint32_t)0x0000FF00UL) <<  8)
-               | ((x & (uint32_t)0x00FF0000UL) >>  8)
-               | ((x & (uint32_t)0xFF000000UL) >> 24);
-}
+#define SWAB32(x) ((uint32_t)(                                         \
+       (((uint32_t)(x) & (uint32_t)0x000000ffUL) << 24) |              \
+       (((uint32_t)(x) & (uint32_t)0x0000ff00UL) <<  8) |              \
+       (((uint32_t)(x) & (uint32_t)0x00ff0000UL) >>  8) |              \
+       (((uint32_t)(x) & (uint32_t)0xff000000UL) >> 24)))
 
 /**
  * Reverse bytes in a 64-bit value.
  */
-INLINE uint64_t swab64(uint64_t x)
-{
-       return (uint64_t)swab32(x >> 32)
-               | ((uint64_t)swab32(x & 0xFFFFFFFFUL) << 32);
-}
+#define SWAB64(x) ((uint64_t)(                                         \
+       (((uint64_t)(x) & (uint64_t)0x00000000000000ffULL) << 56) |     \
+       (((uint64_t)(x) & (uint64_t)0x000000000000ff00ULL) << 40) |     \
+       (((uint64_t)(x) & (uint64_t)0x0000000000ff0000ULL) << 24) |     \
+       (((uint64_t)(x) & (uint64_t)0x00000000ff000000ULL) <<  8) |     \
+       (((uint64_t)(x) & (uint64_t)0x000000ff00000000ULL) >>  8) |     \
+       (((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24) |     \
+       (((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40) |     \
+       (((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56)))
+#endif
+
+#if CPU_BYTE_ORDER == CPU_LITTLE_ENDIAN
+#define cpu_to_le16(x) \
+       (x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint16_t)))
+#define cpu_to_le32(x) \
+       (x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint32_t)))
+#define cpu_to_le64(x) \
+       (x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint64_t)))
+#define cpu_to_be16(x) \
+       SWAB16(x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint16_t)))
+#define cpu_to_be32(x) \
+       SWAB32(x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint32_t)))
+#define cpu_to_be64(x) \
+       SWAB64(x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint64_t)))
+#elif CPU_BYTE_ORDER == CPU_BIG_ENDIAN
+#define cpu_to_le16(x) \
+       SWAB16(x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint16_t)))
+#define cpu_to_le32(x) \
+       SWAB32(x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint32_t)))
+#define cpu_to_le64(x) \
+       SWAB64(x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint64_t)))
+#define cpu_to_be16(x) \
+       (x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint16_t)))
+#define cpu_to_be32(x) \
+       (x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint32_t)))
+#define cpu_to_be64(x) \
+       (x + STATIC_ASSERT_EXPR(sizeof(x) == sizeof(uint64_t)))
+#else
+#error "unrecognized CPU endianness"
+#endif
+
+#define be16_to_cpu(x)         cpu_to_be16(x)
+#define le16_to_cpu(x)         cpu_to_le16(x)
+#define be32_to_cpu(x)         cpu_to_be32(x)
+#define le32_to_cpu(x)         cpu_to_le32(x)
+#define be64_to_cpu(x)         cpu_to_be64(x)
+#define le64_to_cpu(x)         cpu_to_le64(x)
+
+#define host_to_net16(x)       cpu_to_be16(x)
+#define net_to_host16(x)       be16_to_cpu(x)
+#define host_to_net32(x)       cpu_to_be32(x)
+#define net_to_host32(x)       be32_to_cpu(x)
+#define host_to_net64(x)       cpu_to_be64(x)
+#define net_to_host64(x)       be64_to_cpu(x)
 
 /**
  * Reverse bytes in a float value.
@@ -85,36 +132,6 @@ INLINE float swab_float(float x)
        return x;
 }
 
-INLINE uint16_t cpu_to_be16(uint16_t x)
-{
-       return (CPU_BYTE_ORDER == CPU_LITTLE_ENDIAN) ? swab16(x) : x;
-}
-
-INLINE uint16_t cpu_to_le16(uint16_t x)
-{
-       return (CPU_BYTE_ORDER == CPU_BIG_ENDIAN) ? swab16(x) : x;
-}
-
-INLINE uint32_t cpu_to_be32(uint32_t x)
-{
-       return (CPU_BYTE_ORDER == CPU_LITTLE_ENDIAN) ? swab32(x) : x;
-}
-
-INLINE uint32_t cpu_to_le32(uint32_t x)
-{
-       return (CPU_BYTE_ORDER == CPU_BIG_ENDIAN) ? swab32(x) : x;
-}
-
-INLINE uint64_t cpu_to_be64(uint64_t x)
-{
-       return (CPU_BYTE_ORDER == CPU_LITTLE_ENDIAN) ? swab64(x) : x;
-}
-
-INLINE uint64_t cpu_to_le64(uint64_t x)
-{
-       return (CPU_BYTE_ORDER == CPU_BIG_ENDIAN) ? swab64(x) : x;
-}
-
 INLINE float cpu_to_be_float(float x)
 {
        return (CPU_BYTE_ORDER == CPU_LITTLE_ENDIAN) ? swab_float(x) : x;
@@ -125,36 +142,6 @@ INLINE float cpu_to_le_float(float x)
        return (CPU_BYTE_ORDER == CPU_BIG_ENDIAN) ? swab_float(x) : x;
 }
 
-INLINE uint16_t be16_to_cpu(uint16_t x)
-{
-       return cpu_to_be16(x);
-}
-
-INLINE uint16_t le16_to_cpu(uint16_t x)
-{
-       return cpu_to_le16(x);
-}
-
-INLINE uint32_t be32_to_cpu(uint32_t x)
-{
-       return cpu_to_be32(x);
-}
-
-INLINE uint32_t le32_to_cpu(uint32_t x)
-{
-       return cpu_to_le32(x);
-}
-
-INLINE uint64_t be64_to_cpu(uint64_t x)
-{
-       return cpu_to_be64(x);
-}
-
-INLINE uint64_t le64_to_cpu(uint64_t x)
-{
-       return cpu_to_le64(x);
-}
-
 INLINE float be_float_to_cpu(float x)
 {
        return cpu_to_be_float(x);
@@ -165,36 +152,6 @@ INLINE float le_float_to_cpu(float x)
        return cpu_to_le_float(x);
 }
 
-INLINE uint16_t host_to_net16(uint16_t x)
-{
-       return cpu_to_be16(x);
-}
-
-INLINE uint16_t net_to_host16(uint16_t x)
-{
-       return be16_to_cpu(x);
-}
-
-INLINE uint32_t host_to_net32(uint32_t x)
-{
-       return cpu_to_be32(x);
-}
-
-INLINE uint32_t net_to_host32(uint32_t x)
-{
-       return be32_to_cpu(x);
-}
-
-INLINE uint64_t host_to_net64(uint64_t x)
-{
-       return cpu_to_be64(x);
-}
-
-INLINE uint64_t net_to_host64(uint64_t x)
-{
-       return be64_to_cpu(x);
-}
-
 INLINE float host_to_net_float(float x)
 {
        return cpu_to_be_float(x);