Well the PGI compiler has
enum _mm_hint
{
_MM_HINT_T0 = 3,
_MM_HINT_T1 = 2,
_MM_HINT_T2 = 1,
_MM_HINT_NTA = 0
};
extern void _mm_prefetch (const void *__P, enum _mm_hint __I);
Intel on my Mac has
/* constants for use with _mm_prefetch */
#define _MM_HINT_T0 1
#define _MM_HINT_T1 2
#define _MM_HINT_T2 3
#define _MM_HINT_NTA 0
extern void __cdecl _mm_prefetch(char const*a, int sel);
clang on my mac has
#define _MM_HINT_T0 1
#define _MM_HINT_T1 2
#define _MM_HINT_T2 3
#define _MM_HINT_NTA 0
/* FIXME: We have to #define this because "sel" must be a constant integer, and
Sema doesn't do any form of constant propagation yet. */
#define _mm_prefetch(a, sel) (__builtin_prefetch((void *)a, 0, sel))
Some GNU headers I found on the web have
/* Constants for use with _mm_prefetch. */
enum _mm_hint
{
_MM_HINT_T0 = 3,
_MM_HINT_T1 = 2,
_MM_HINT_T2 = 1,
_MM_HINT_NTA = 0
};
static __inline void
_mm_prefetch (void *__P, enum _mm_hint __I)
Though it may be non-conforming I think it still needs to be supported. It
seems _MM_HINT* etc and friends always exist, what about just not using 1, 2 3
etc but consistently using the macros would work and not require adding to
configure.
Barry
On Aug 26, 2010, at 4:26 AM, Jed Brown wrote:
> On Wed, 25 Aug 2010 18:19:50 -0500, Barry Smith <bsmith at mcs.anl.gov> wrote:
>>
>> libfast in: /users/nyevik/MANUALBUILD/petsc-3.1-p4/src/mat/impls/aij/seq
>> inode.c: In function 'PetscErrorCode MatMult_SeqAIJ_Inode(_p_Mat*, _p_Vec*,
>> _p_Vec*)':
>> inode.c:426: error: invalid conversion from 'int' to '_mm_hint'
>> inode.c:426: error: initializing argument 2 of 'void _mm_prefetch(const
>> void*, _mm_hint)'
>> inode.c:427: error: invalid conversion from 'int' to '_mm_hint'
>> inode.c:427: error: initializing argument 2 of 'void _mm_prefetch(const
>> void*, _mm_hint)'
>>
>> The PETSc code currently handles all this as the second argument is an int.
>> This has to be fixed in petsc-dev to handle the case when int cannot be cast
>> to _mm_hint
>
> The Intel Intrinsics manual [1] specifies that the prototype is
>
> void _mm_prefetch(char const *a, int sel)
>
> so this compiler is non-conforming. What is it? We may still need a
> workaround, but should confirm that it has been filed as a bug.
>
> Jed
>
> [1] see page 77 of http://software.intel.com/file/6373
