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/* { dg-do run } */
/* { dg-require-effective-target int32plus } */
/* { dg-options "-O -fdump-tree-forwprop4 -fdump-tree-dse1" } */
extern void abort (void);
union U { int i; char c[4]; short s[2]; };
char __attribute__((noinline,noclone)) foo(int i)
{
union U u;
u.i = i;
/* This should be equivalent to (char) i. */
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
return u.c[0];
#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
return u.c[3];
#else
return 0x04;
#endif
}
short __attribute__((noinline,noclone)) baz(int i)
{
union U u;
u.i = i;
/* This should be equivalent to (char) i. */
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
return u.s[0];
#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
return u.s[1];
#else
return 0x0304;
#endif
}
char __attribute__((noinline,noclone)) bar(int j)
{
union U u;
u.i = j;
/* This gets simplified to a BIT_FIELD_REF. */
return u.c[2];
}
int main()
{
if (foo (0x01020304) != 0x04)
abort ();
if (baz (0x01020304) != 0x0304)
abort ();
return 0;
}
/* { dg-final { scan-tree-dump "\\(char\\) i_" "forwprop4" } } */
/* { dg-final { scan-tree-dump "\\(short int\\) i_" "forwprop4" } } */
/* { dg-final { scan-tree-dump-not "u.i =" "dse1" } } */
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