| Message ID | 20200917163106.49351-4-philmd@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | qemu/bswap: Let cpu_to_endian() functions handle constant expressions | expand |
On 9/17/20 9:31 AM, Philippe Mathieu-Daudé wrote: > From: Philippe Mathieu-Daudé <f4bug@amsat.org> > > We already have the const_endian() macros for 16-bit and > 32-bit values. Implement the 64-bit equivalent macros. > > Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> > --- > include/qemu/bswap.h | 22 +++++++++++++++++++++- > 1 file changed, 21 insertions(+), 1 deletion(-) > > diff --git a/include/qemu/bswap.h b/include/qemu/bswap.h > index 6885984e00c..de256cea3ab 100644 > --- a/include/qemu/bswap.h > +++ b/include/qemu/bswap.h > @@ -83,11 +83,20 @@ static inline void bswap64s(uint64_t *s) > #endif > > /* > - * Same as cpu_to_{be,le}{16,32} described below, except that gcc will > + * Same as cpu_to_{be,le}{16,32,64} described below, except that gcc will > * figure the result is a compile-time constant if you pass in a constant. > * So this can be used to initialize static variables. > */ > #if defined(HOST_WORDS_BIGENDIAN) > +# define const_le64(_x) \ > + ((((_x) & 0x00000000000000ffU) << 56) | \ > + (((_x) & 0x000000000000ff00U) << 40) | \ > + (((_x) & 0x0000000000ff0000U) << 24) | \ > + (((_x) & 0x00000000ff000000U) << 8) | \ > + (((_x) & 0x000000ff00000000U) >> 8) | \ > + (((_x) & 0x0000ff0000000000U) >> 24) | \ > + (((_x) & 0x00ff000000000000U) >> 40) | \ > + (((_x) & 0xff00000000000000U) >> 56)) > # define const_le32(_x) \ > ((((_x) & 0x000000ffU) << 24) | \ > (((_x) & 0x0000ff00U) << 8) | \ > @@ -96,11 +105,22 @@ static inline void bswap64s(uint64_t *s) > # define const_le16(_x) \ > ((((_x) & 0x00ff) << 8) | \ > (((_x) & 0xff00) >> 8)) > +# define const_be64(_x) (_x) > # define const_be32(_x) (_x) > # define const_be16(_x) (_x) > #else > +# define const_le64(_x) (_x) > # define const_le32(_x) (_x) > # define const_le16(_x) (_x) > +# define const_be64(_x) \ > + ((((_x) & 0x00000000000000ffU) << 56) | \ > + (((_x) & 0x000000000000ff00U) << 40) | \ > + (((_x) & 0x0000000000ff0000U) << 24) | \ > + (((_x) & 0x00000000ff000000U) << 8) | \ > + (((_x) & 0x000000ff00000000U) >> 8) | \ > + (((_x) & 0x0000ff0000000000U) >> 24) | \ > + (((_x) & 0x00ff000000000000U) >> 40) | \ > + (((_x) & 0xff00000000000000U) >> 56)) > # define const_be32(_x) \ > ((((_x) & 0x000000ffU) << 24) | \ > (((_x) & 0x0000ff00U) << 8) | \ > This duplication suggests that we define these as const_bswap64, and define const_le64/be64 on top of that. Similar for the other defines as you're moving them. r~
diff --git a/include/qemu/bswap.h b/include/qemu/bswap.h index 6885984e00c..de256cea3ab 100644 --- a/include/qemu/bswap.h +++ b/include/qemu/bswap.h @@ -83,11 +83,20 @@ static inline void bswap64s(uint64_t *s) #endif /* - * Same as cpu_to_{be,le}{16,32} described below, except that gcc will + * Same as cpu_to_{be,le}{16,32,64} described below, except that gcc will * figure the result is a compile-time constant if you pass in a constant. * So this can be used to initialize static variables. */ #if defined(HOST_WORDS_BIGENDIAN) +# define const_le64(_x) \ + ((((_x) & 0x00000000000000ffU) << 56) | \ + (((_x) & 0x000000000000ff00U) << 40) | \ + (((_x) & 0x0000000000ff0000U) << 24) | \ + (((_x) & 0x00000000ff000000U) << 8) | \ + (((_x) & 0x000000ff00000000U) >> 8) | \ + (((_x) & 0x0000ff0000000000U) >> 24) | \ + (((_x) & 0x00ff000000000000U) >> 40) | \ + (((_x) & 0xff00000000000000U) >> 56)) # define const_le32(_x) \ ((((_x) & 0x000000ffU) << 24) | \ (((_x) & 0x0000ff00U) << 8) | \ @@ -96,11 +105,22 @@ static inline void bswap64s(uint64_t *s) # define const_le16(_x) \ ((((_x) & 0x00ff) << 8) | \ (((_x) & 0xff00) >> 8)) +# define const_be64(_x) (_x) # define const_be32(_x) (_x) # define const_be16(_x) (_x) #else +# define const_le64(_x) (_x) # define const_le32(_x) (_x) # define const_le16(_x) (_x) +# define const_be64(_x) \ + ((((_x) & 0x00000000000000ffU) << 56) | \ + (((_x) & 0x000000000000ff00U) << 40) | \ + (((_x) & 0x0000000000ff0000U) << 24) | \ + (((_x) & 0x00000000ff000000U) << 8) | \ + (((_x) & 0x000000ff00000000U) >> 8) | \ + (((_x) & 0x0000ff0000000000U) >> 24) | \ + (((_x) & 0x00ff000000000000U) >> 40) | \ + (((_x) & 0xff00000000000000U) >> 56)) # define const_be32(_x) \ ((((_x) & 0x000000ffU) << 24) | \ (((_x) & 0x0000ff00U) << 8) | \