| /* PR tree-optimization/83821 - local aggregate initialization defeats |
| strlen optimization |
| Verify that a strlen() call is eliminated for a pointer to a region |
| of memory allocated by calloc() even if one or more nul bytes are |
| written into it. |
| { dg-do compile } |
| { dg-options "-O2 -fno-tree-vectorize -fdump-tree-optimized" } */ |
| |
| unsigned n0, n1; |
| |
| void* elim_strlen_calloc_store_memset_1 (unsigned a, unsigned b) |
| { |
| char *p = __builtin_calloc (a, 1); |
| |
| p[0] = '\0'; |
| p[1] = '\0'; |
| p[2] = '\0'; |
| p[3] = '\0'; |
| |
| __builtin_memset (p, 0, b); |
| |
| n0 = __builtin_strlen (p); |
| |
| return p; |
| } |
| |
| void* elim_strlen_calloc_store_memset_2 (unsigned a, unsigned b, unsigned c) |
| { |
| char *p = __builtin_calloc (a, 1); |
| |
| p[1] = '\0'; |
| __builtin_memset (p, 0, b); |
| |
| n0 = __builtin_strlen (p); |
| |
| p[3] = 0; |
| __builtin_memset (p, 0, c); |
| |
| n1 = __builtin_strlen (p); |
| |
| return p; |
| } |
| |
| /* { dg-final { scan-tree-dump-not "__builtin_strlen" "optimized" } } */ |