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/* Inspired by 'libgomp.oacc-c-c++-common/nvptx-sese-1.c'. */
/* { dg-additional-options -O1 } */
/* { dg-additional-options -fdump-tree-dom3-raw } */
extern int
__attribute__((const))
foo1 (int);
int f1 (int r)
{
if (foo1 (r)) /* If this first 'if' holds... */
r *= 2; /* ..., 'r' now has a zero-value lower-most bit... */
if (r & 1) /* ..., so this second 'if' can never hold... */
{ /* ..., so this is unreachable. */
/* In constrast, if the first 'if' does not hold ('foo1 (r) == 0'), the
second 'if' may hold, but we know ('foo1' being 'const') that
'foo1 (r) == 0', so don't have to re-evaluate it here: */
r += foo1 (r);
}
return r;
}
/* Thus, if optimizing, we only ever expect one call of 'foo1'.
{ dg-final { scan-tree-dump-times {gimple_call <foo1,} 1 dom3 } } */
extern int
__attribute__((const))
foo2 (int);
int f2 (int r)
{
if (foo2 (r))
r *= 8;
if (r & 7)
r += foo2 (r);
return r;
}
/* { dg-final { scan-tree-dump-times {gimple_call <foo2,} 1 dom3 } } */
extern int
__attribute__((const))
foo3 (int);
int f3 (int r)
{
if (foo3 (r))
r <<= 4;
if ((r & 64) && ((r & 8) || (r & 4) || (r & 2) || (r & 1)))
r += foo3 (r);
return r;
}
/* { dg-final { scan-tree-dump-times {gimple_call <foo3,} 1 dom3 } } */
extern int
__attribute__((const))
foo4 (int);
int f4 (int r)
{
if (foo4 (r))
r *= 8;
if ((r >> 1) & 2)
r += foo4 (r);
return r;
}
/* { dg-final { scan-tree-dump-times {gimple_call <foo4,} 1 dom3 } } */
extern int
__attribute__((const))
foo5 (int);
int f5 (int r) /* Works for both 'signed' and 'unsigned'. */
{
if (foo5 (r))
r *= 2;
if ((r % 2) != 0)
r += foo5 (r);
return r;
}
/* { dg-final { scan-tree-dump-times {gimple_call <foo5,} 1 dom3 } } */
extern int
__attribute__((const))
foo6 (int);
int f6 (unsigned int r) /* 'unsigned' is important here. */
{
if (foo6 (r))
r *= 2;
if ((r % 2) == 1)
r += foo6 (r);
return r;
}
/* { dg-final { scan-tree-dump-times {gimple_call <foo6,} 1 dom3 } } */
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