| /* 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" } } */ |