/* PR tree-optimization/83821 - local aggregate initialization defeats strlen optimization { dg-do compile } { dg-options "-O2 -Wall -fdump-tree-optimized" } */ #include "strlenopt.h" char *p_p2, *p_p5, *p_p9, *p_p14; unsigned n0, n1, n2, n3, n4; static inline __attribute__ ((always_inline)) void elim_strlen_of_consecutive_strcpy (char *p) { p_p2 = p + 2; __builtin_strcpy (p_p2, "12"); p_p5 = p_p2 + 3; __builtin_strcpy (p_p5, "124"); p_p9 = p_p5 + 4; __builtin_strcpy (p_p9, "1245"); p_p14 = p_p9 + 5; n0 = __builtin_strlen (p); n1 = __builtin_strlen (p_p2); n2 = __builtin_strlen (p_p5); n3 = __builtin_strlen (p_p9); /* The following isn't handled yet: n4 = __builtin_strlen (p_p14); */ if (n0 || n1 != 2 || n2 != 3 || n3 != 4) __builtin_abort (); } void elim_strlen_of_consecutive_strcpy_in_alloca (unsigned n) { /* Only known sizes are handled so far. */ n = 14; char *p = __builtin_alloca (n); *p = '\0'; elim_strlen_of_consecutive_strcpy (p); } void elim_strlen_of_consecutive_strcpy_in_vla (unsigned n) { /* Only known sizes are handled so far. */ n = 14; char vla[n]; *vla = '\0'; elim_strlen_of_consecutive_strcpy (vla); } void elim_strlen_of_consecutive_strcpy_in_malloc (unsigned n) { char *p = __builtin_malloc (n); *p = '\0'; elim_strlen_of_consecutive_strcpy (p); } void elim_strlen_of_consecutive_strcpy_in_calloc (unsigned n) { char *p = __builtin_calloc (n, 1); /* Do not store into *P to verify that strlen knows it's zero. */ elim_strlen_of_consecutive_strcpy (p); } /* { dg-final { scan-tree-dump-not "abort" "optimized" } } */