Simplify fixes for unreachable code

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
This commit is contained in:
Dave Rodgman 2023-09-05 18:12:33 +01:00
parent cfa722324c
commit 7e1e7be8fc
2 changed files with 7 additions and 47 deletions

View file

@ -77,40 +77,19 @@ size_t mbedtls_mpi_core_bitlen(const mbedtls_mpi_uint *A, size_t A_limbs)
return 0;
}
/* Convert a big-endian byte array aligned to the size of mbedtls_mpi_uint
* into the storage form used by mbedtls_mpi. */
static mbedtls_mpi_uint mpi_bigendian_to_host_c(mbedtls_mpi_uint a)
{
uint8_t i;
unsigned char *a_ptr;
mbedtls_mpi_uint tmp = 0;
for (i = 0, a_ptr = (unsigned char *) &a; i < ciL; i++, a_ptr++) {
tmp <<= CHAR_BIT;
tmp |= (mbedtls_mpi_uint) *a_ptr;
}
return tmp;
}
static mbedtls_mpi_uint mpi_bigendian_to_host(mbedtls_mpi_uint a)
{
if (MBEDTLS_IS_BIG_ENDIAN) {
/* Nothing to do on bigendian systems. */
return a;
} else {
MBEDTLS_IGNORE_UNREACHABLE_BEGIN
switch (sizeof(mbedtls_mpi_uint)) {
case 4:
#if defined(MBEDTLS_HAVE_INT32)
return (mbedtls_mpi_uint) MBEDTLS_BSWAP32((uint32_t) a);
case 8:
#elif defined(MBEDTLS_HAVE_INT64)
return (mbedtls_mpi_uint) MBEDTLS_BSWAP64((uint64_t) a);
}
/* Fall back to C-based reordering if we don't know the byte order
* or we couldn't use a compiler-specific builtin. */
return mpi_bigendian_to_host_c(a);
MBEDTLS_IGNORE_UNREACHABLE_END
#else
#error "This is one of several places that need to be adapted to support a new limb size"
#endif
}
}

View file

@ -334,23 +334,4 @@ static inline void mbedtls_xor_no_simd(unsigned char *r,
#define MBEDTLS_OPTIMIZE_FOR_PERFORMANCE
#endif
/* Define macros that can be used to disable warnings about unreachable code. */
#if defined(__clang__)
#define MBEDTLS_PRAGMA(x) _Pragma(#x)
#define MBEDTLS_IGNORE_UNREACHABLE_BEGIN \
MBEDTLS_PRAGMA(clang diagnostic push) \
MBEDTLS_PRAGMA(clang diagnostic ignored "-Wunreachable-code")
#define MBEDTLS_IGNORE_UNREACHABLE_END \
MBEDTLS_PRAGMA(clang diagnostic pop)
#else
#define MBEDTLS_IGNORE_UNREACHABLE_BEGIN
#define MBEDTLS_IGNORE_UNREACHABLE_END
#endif
#endif /* MBEDTLS_LIBRARY_COMMON_H */