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/* PR tree-optimization/83821 - local aggregate initialization defeats
strlen optimization
Verify that a strlen() call is not eliminated for a pointer to a region
of memory allocated by calloc() if a byte is written into the region
that isn't known to be nul.
{ dg-do compile }
{ dg-options "-O2 -fdump-tree-optimized" } */
unsigned n0, n1;
void*
keep_strlen_calloc_store_cst_memset (int i, unsigned a, unsigned b)
{
char *p = __builtin_calloc (a, 1);
p[i] = 'x';
__builtin_memset (p, 0, b);
n0 = __builtin_strlen (p);
return p;
}
void*
keep_strlen_calloc_store_var_memset (int i, int x, unsigned a, unsigned b)
{
char *p = __builtin_calloc (a, 1);
p[i] = x;
__builtin_memset (p, 0, b);
n0 = __builtin_strlen (p);
return p;
}
void*
keep_strlen_calloc_store_memset_2 (int i, int x, unsigned a, unsigned b, unsigned c)
{
char *p = __builtin_calloc (a, 1);
p[i] = x;
__builtin_memset (p, 0, b);
n0 = __builtin_strlen (p);
p[3] = x;
__builtin_memset (p, 0, c);
n1 = __builtin_strlen (p);
return p;
}
/* { dg-final { scan-tree-dump-times "__builtin_strlen" 4 "optimized" } } */
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