/* PR middle-end/78257 - missing memcmp optimization with constant arrays { dg-do compile } { dg-options "-O -Wall -fdump-tree-optimized" } */ typedef __INT8_TYPE__ int8_t; typedef __INT16_TYPE__ int16_t; typedef __INT32_TYPE__ int32_t; typedef __SIZE_TYPE__ size_t; extern void* memchr (const void*, int, size_t); /* Verify that initializers for flexible array members are handled correctly. */ struct SX { /* offset */ /* 0 */ int32_t n; /* 4 */ int8_t: 1; /* 6 */ int16_t a[]; }; _Static_assert (__builtin_offsetof (struct SX, a) == 6); const struct SX sx = { 0x11121314, { 0x2122, 0x3132, 0x4142, 0x5152 } }; const char sx_rep[] = { #if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ 0x11, 0x12, 0x13, 0x14, 0, 0, 0x21, 0x22, 0x31, 0x32, 0x41, 0x42, 0x51, 0x52 #else 0x14, 0x13, 0x12, 0x11, 0, 0, 0x22, 0x21, 0x32, 0x31, 0x42, 0x41, 0x52, 0x51 #endif }; void test_find (void) { int n = 0, nb = (const char*)&sx.a[4] - (const char*)&sx; const char *p = (const char*)&sx, *q = sx_rep; if (nb != sizeof sx_rep) __builtin_abort (); n += p == memchr (p, q[ 0], nb); n += p + 1 == memchr (p, q[ 1], nb); n += p + 2 == memchr (p, q[ 2], nb); n += p + 3 == memchr (p, q[ 3], nb); n += p + 4 == memchr (p, q[ 4], nb); n += p + 4 == memchr (p, q[ 5], nb); n += p + 6 == memchr (p, q[ 6], nb); n += p + 7 == memchr (p, q[ 7], nb); n += p + 8 == memchr (p, q[ 8], nb); n += p + 9 == memchr (p, q[ 9], nb); n += p + 10 == memchr (p, q[10], nb); n += p + 11 == memchr (p, q[11], nb); n += p + 12 == memchr (p, q[12], nb); n += p + 13 == memchr (p, q[13], nb); if (n != 14) __builtin_abort (); } void test_not_find (void) { int n = 0, nb = (const char*)&sx.a[4] - (const char*)&sx; const char *p = (const char*)&sx, *q = sx_rep; if (nb != sizeof sx_rep) __builtin_abort (); n += 0 == memchr (p, 0xff, nb); n += 0 == memchr (p + 1, q[ 0], nb - 1); n += 0 == memchr (p + 2, q[ 1], nb - 2); n += 0 == memchr (p + 3, q[ 2], nb - 3); n += 0 == memchr (p + 4, q[ 3], nb - 4); n += 0 == memchr (p + 6, q[ 4], nb - 6); n += 0 == memchr (p + 7, q[ 6], nb - 7); n += 0 == memchr (p + 8, q[ 7], nb - 8); n += 0 == memchr (p + 9, q[ 8], nb - 9); n += 0 == memchr (p + 10, q[ 9], nb - 10); n += 0 == memchr (p + 11, q[10], nb - 11); n += 0 == memchr (p + 12, q[11], nb - 12); n += 0 == memchr (p + 13, q[12], nb - 13); n += 0 == memchr (p + 14, q[13], nb - 14); if (n != 14) __builtin_abort (); } /* { dg-final { scan-tree-dump-not "abort" "optimized" } } */