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/* Test that __builtin_prefetch does no harm.
Prefetch data using a variety of storage classes and address
expressions. */
int glob_int_arr[100];
int *glob_ptr_int = glob_int_arr;
int glob_int = 4;
static stat_int_arr[100];
static int *stat_ptr_int = stat_int_arr;
static int stat_int;
struct S {
int a;
short b, c;
char d[8];
struct S *next;
};
struct S str;
struct S *ptr_str = &str;
/* Prefetch global variables using the address of the variable. */
void
simple_global ()
{
__builtin_prefetch (glob_int_arr, 0, 0);
__builtin_prefetch (glob_ptr_int, 0, 0);
__builtin_prefetch (&glob_int, 0, 0);
}
/* Prefetch file-level static variables using the address of the variable. */
void
simple_file ()
{
__builtin_prefetch (stat_int_arr, 0, 0);
__builtin_prefetch (stat_ptr_int, 0, 0);
__builtin_prefetch (&stat_int, 0, 0);
}
/* Prefetch local static variables using the address of the variable. */
void
simple_static_local ()
{
static int gx[100];
static int *hx = gx;
static int ix;
__builtin_prefetch (gx, 0, 0);
__builtin_prefetch (hx, 0, 0);
__builtin_prefetch (&ix, 0, 0);
}
/* Prefetch local stack variables using the address of the variable. */
void
simple_local ()
{
int gx[100];
int *hx = gx;
int ix;
__builtin_prefetch (gx, 0, 0);
__builtin_prefetch (hx, 0, 0);
__builtin_prefetch (&ix, 0, 0);
}
/* Prefetch arguments using the address of the variable. */
void
simple_arg (int g[100], int *h, int i)
{
__builtin_prefetch (g, 0, 0);
__builtin_prefetch (h, 0, 0);
__builtin_prefetch (&i, 0, 0);
}
/* Prefetch using address expressions involving global variables. */
void
expr_global (void)
{
__builtin_prefetch (&str, 0, 0);
__builtin_prefetch (ptr_str, 0, 0);
__builtin_prefetch (&str.b, 0, 0);
__builtin_prefetch (&ptr_str->b, 0, 0);
__builtin_prefetch (&str.d, 0, 0);
__builtin_prefetch (&ptr_str->d, 0, 0);
__builtin_prefetch (str.next, 0, 0);
__builtin_prefetch (ptr_str->next, 0, 0);
__builtin_prefetch (str.next->d, 0, 0);
__builtin_prefetch (ptr_str->next->d, 0, 0);
__builtin_prefetch (&glob_int_arr, 0, 0);
__builtin_prefetch (glob_ptr_int, 0, 0);
__builtin_prefetch (&glob_int_arr[2], 0, 0);
__builtin_prefetch (&glob_ptr_int[3], 0, 0);
__builtin_prefetch (glob_int_arr+3, 0, 0);
__builtin_prefetch (glob_int_arr+glob_int, 0, 0);
__builtin_prefetch (glob_ptr_int+5, 0, 0);
__builtin_prefetch (glob_ptr_int+glob_int, 0, 0);
}
/* Prefetch using address expressions involving local variables. */
void
expr_local (void)
{
int b[10];
int *pb = b;
struct S t;
struct S *pt = &t;
int j = 4;
__builtin_prefetch (&t, 0, 0);
__builtin_prefetch (pt, 0, 0);
__builtin_prefetch (&t.b, 0, 0);
__builtin_prefetch (&pt->b, 0, 0);
__builtin_prefetch (&t.d, 0, 0);
__builtin_prefetch (&pt->d, 0, 0);
__builtin_prefetch (t.next, 0, 0);
__builtin_prefetch (pt->next, 0, 0);
__builtin_prefetch (t.next->d, 0, 0);
__builtin_prefetch (pt->next->d, 0, 0);
__builtin_prefetch (&b, 0, 0);
__builtin_prefetch (pb, 0, 0);
__builtin_prefetch (&b[2], 0, 0);
__builtin_prefetch (&pb[3], 0, 0);
__builtin_prefetch (b+3, 0, 0);
__builtin_prefetch (b+j, 0, 0);
__builtin_prefetch (pb+5, 0, 0);
__builtin_prefetch (pb+j, 0, 0);
}
int
main ()
{
simple_global ();
simple_file ();
simple_static_local ();
simple_local ();
simple_arg (glob_int_arr, glob_ptr_int, glob_int);
str.next = &str;
expr_global ();
expr_local ();
exit (0);
}
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