Hi Dave.
> Sparc64 requires type-aligned memory access. Since data buffers may not
> be properly aligned, implement a safe copy from memory per data type.
>
> Signed-off-by: Dave Kleikamp <[email protected]>
> ---
> defs.h | 41 +++++++++++++++++++++++++++++++++++++++++
> 1 files changed, 41 insertions(+), 0 deletions(-)
>
> diff --git a/defs.h b/defs.h
> index e3afc58..d9d4559 100644
> --- a/defs.h
> +++ b/defs.h
> @@ -2187,6 +2187,45 @@ struct builtin_debug_table {
> * Facilitators for pulling correctly-sized data out of a buffer at a
> * known address.
> */
> +
> +#ifdef NEED_ALIGNED_MEM_ACCESS
> +
> +#define DEF_LOADER(TYPE) \
> +static inline TYPE \
> +load_##TYPE (char *addr) \
> +{ \
> + TYPE ret; \
> + size_t i = sizeof(TYPE); \
> + while (i--) \
> + ((char *)&ret)[i] = addr[i]; \
> + return ret; \
> +}
> +
> +DEF_LOADER(int);
> +DEF_LOADER(uint);
> +DEF_LOADER(long);
> +DEF_LOADER(ulong);
> +DEF_LOADER(ulonglong);
> +DEF_LOADER(ushort);
> +DEF_LOADER(short);
> +typedef void *pointer_t;
> +DEF_LOADER(pointer_t);
> +
> +#define LOADER(TYPE) load_##TYPE
A simpler model would be
#define LOADER(TYPE, addr) \
({ \
TYPE ret; \
memcpy(&ret, (void *)addr, sizeof(TYPE)); \
ret; \
})
I would expect the compiler to optimize this away for archs
that do not require aligned access.
Quick test:
#include <string.h>
#include <stdio.h>
#define LOADER(TYPE, addr) \
({ \
TYPE ret; \
memcpy(&ret, (void*)addr, sizeof(TYPE)); \
ret; \
})
#define INT(ADDR) LOADER(int, ADDR)
void main(void)
{
int i = 37;
int j = -17;
printf("i=%d j=%d\n", INT(&i), INT(&j));
}
Sam
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