builtin-object-size-1.c

来自「linux下编程用 编译软件」· C语言 代码 · 共 437 行

/* { dg-do run } */
/* { dg-options "-O2" } */

typedef __SIZE_TYPE__ size_t;
extern void abort (void);
extern void exit (int);
extern void *malloc (size_t);
extern void *calloc (size_t, size_t);
extern void *alloca (size_t);
extern void *memcpy (void *, const void *, size_t);
extern void *memset (void *, int, size_t);
extern char *strcpy (char *, const char *);

struct A
{
  char a[10];
  int b;
  char c[10];
} y, w[4];

extern char exta[];
extern char extb[30];
extern struct A zerol[0];

void
__attribute__ ((noinline))
test1 (void *q, int x)
{
  struct A a;
  void *p = &a.a[3], *r;
  char var[x + 10];
  if (x < 0)
    r = &a.a[9];
  else
    r = &a.c[1];
  if (__builtin_object_size (p, 0)
      != sizeof (a) - __builtin_offsetof (struct A, a) - 3)
    abort ();
  if (__builtin_object_size (&a.c[9], 0)
      != sizeof (a) - __builtin_offsetof (struct A, c) - 9)
    abort ();
  if (__builtin_object_size (q, 0) != (size_t) -1)
    abort ();
  if (__builtin_object_size (r, 0)
      != sizeof (a) - __builtin_offsetof (struct A, a) - 9)
    abort ();
  if (x < 6)
    r = &w[2].a[1];
  else
    r = &a.a[6];
  if (__builtin_object_size (&y, 0)
      != sizeof (y))
    abort ();
  if (__builtin_object_size (w, 0)
      != sizeof (w))
    abort ();
  if (__builtin_object_size (&y.b, 0)
      != sizeof (a) - __builtin_offsetof (struct A, b))
    abort ();
  if (__builtin_object_size (r, 0)
      != 2 * sizeof (w[0]) - __builtin_offsetof (struct A, a) - 1)
    abort ();
  if (x < 20)
    r = malloc (30);
  else
    r = calloc (2, 16);
  if (__builtin_object_size (r, 0) != 2 * 16)
    abort ();
  if (x < 20)
    r = malloc (30);
  else
    r = calloc (2, 14);
  if (__builtin_object_size (r, 0) != 30)
    abort ();
  if (x < 30)
    r = malloc (sizeof (a));
  else
    r = &a.a[3];
  if (__builtin_object_size (r, 0) != sizeof (a))
    abort ();
  r = memcpy (r, "a", 2);
  if (__builtin_object_size (r, 0) != sizeof (a))
    abort ();
  r = memcpy (r + 2, "b", 2) + 2;
  if (__builtin_object_size (r, 0) != sizeof (a) - 4)
    abort ();
  r = &a.a[4];
  r = memset (r, 'a', 2);
  if (__builtin_object_size (r, 0)
      != sizeof (a) - __builtin_offsetof (struct A, a) - 4)
    abort ();
  r = memset (r + 2, 'b', 2) + 2;
  if (__builtin_object_size (r, 0)
      != sizeof (a) - __builtin_offsetof (struct A, a) - 8)
    abort ();
  r = &a.a[1];
  r = strcpy (r, "ab");
  if (__builtin_object_size (r, 0)
      != sizeof (a) - __builtin_offsetof (struct A, a) - 1)
    abort ();
  r = strcpy (r + 2, "cd") + 2;
  if (__builtin_object_size (r, 0)
      != sizeof (a) - __builtin_offsetof (struct A, a) - 5)
    abort ();
  if (__builtin_object_size (exta, 0) != (size_t) -1)
    abort ();
  if (__builtin_object_size (exta + 10, 0) != (size_t) -1)
    abort ();
  if (__builtin_object_size (&exta[5], 0) != (size_t) -1)
    abort ();
  if (__builtin_object_size (extb, 0) != sizeof (extb))
    abort ();
  if (__builtin_object_size (extb + 10, 0) != sizeof (extb) - 10)
    abort ();
  if (__builtin_object_size (&extb[5], 0) != sizeof (extb) - 5)
    abort ();
  if (__builtin_object_size (var, 0) != (size_t) -1)
    abort ();
  if (__builtin_object_size (var + 10, 0) != (size_t) -1)
    abort ();
  if (__builtin_object_size (&var[5], 0) != (size_t) -1)
    abort ();
  if (__builtin_object_size (zerol, 0) != 0)
    abort ();
  if (__builtin_object_size (&zerol, 0) != 0)
    abort ();
  if (__builtin_object_size (&zerol[0], 0) != 0)
    abort ();
  if (__builtin_object_size (zerol[0].a, 0) != 0)
    abort ();
  if (__builtin_object_size (&zerol[0].a[0], 0) != 0)
    abort ();
  if (__builtin_object_size (&zerol[0].b, 0) != 0)
    abort ();
  if (__builtin_object_size ("abcdefg", 0) != sizeof ("abcdefg"))
    abort ();
  if (__builtin_object_size ("abcd\0efg", 0) != sizeof ("abcd\0efg"))
    abort ();
  if (__builtin_object_size (&"abcd\0efg", 0) != sizeof ("abcd\0efg"))
    abort ();
  if (__builtin_object_size (&"abcd\0efg"[0], 0) != sizeof ("abcd\0efg"))
    abort ();
  if (__builtin_object_size (&"abcd\0efg"[4], 0) != sizeof ("abcd\0efg") - 4)
    abort ();
  if (__builtin_object_size ("abcd\0efg" + 5, 0) != sizeof ("abcd\0efg") - 5)
    abort ();
  if (__builtin_object_size (L"abcdefg", 0) != sizeof (L"abcdefg"))
    abort ();
  r = (char *) L"abcd\0efg";
  if (__builtin_object_size (r + 2, 0) != sizeof (L"abcd\0efg") - 2)
    abort ();
}

size_t l1 = 1;

void
__attribute__ ((noinline))
test2 (void)
{
  struct B { char buf1[10]; char buf2[10]; } a;
  char *r, buf3[20];
  int i;

  if (sizeof (a) != 20)
    return;

  r = buf3;
  for (i = 0; i < 4; ++i)
    {
      if (i == l1 - 1)
	r = &a.buf1[1];
      else if (i == l1)
	r = &a.buf2[7];
      else if (i == l1 + 1)
	r = &buf3[5];
      else if (i == l1 + 2)
	r = &a.buf1[9];
    }
  if (__builtin_object_size (r, 0) != 20)
    abort ();
  r = &buf3[20];
  for (i = 0; i < 4; ++i)
    {
      if (i == l1 - 1)
	r = &a.buf1[7];
      else if (i == l1)
	r = &a.buf2[7];
      else if (i == l1 + 1)
	r = &buf3[5];
      else if (i == l1 + 2)
	r = &a.buf1[9];
    }
  if (__builtin_object_size (r, 0) != 15)
    abort ();
  r += 8;
  if (__builtin_object_size (r, 0) != 7)
    abort ();
  if (__builtin_object_size (r + 6, 0) != 1)
    abort ();
  r = &buf3[18];
  for (i = 0; i < 4; ++i)
    {
      if (i == l1 - 1)
	r = &a.buf1[9];
      else if (i == l1)
	r = &a.buf2[9];
      else if (i == l1 + 1)
	r = &buf3[5];
      else if (i == l1 + 2)
	r = &a.buf1[4];
    }
  if (__builtin_object_size (r + 12, 0) != 4)
    abort ();
}

void
__attribute__ ((noinline))
test3 (void)
{
  char buf4[10];
  struct B { struct A a[2]; struct A b; char c[4]; char d; double e;
	     _Complex double f; } x;
  double y;
  _Complex double z;
  double *dp;

  if (__builtin_object_size (buf4, 0) != sizeof (buf4))
    abort ();
  if (__builtin_object_size (&buf4, 0) != sizeof (buf4))
    abort ();
  if (__builtin_object_size (&buf4[0], 0) != sizeof (buf4))
    abort ();
  if (__builtin_object_size (&buf4[1], 0) != sizeof (buf4) - 1)
    abort ();
  if (__builtin_object_size (&x, 0) != sizeof (x))
    abort ();
  if (__builtin_object_size (&x.a, 0) != sizeof (x))
    abort ();
  if (__builtin_object_size (&x.a[0], 0) != sizeof (x))
    abort ();
  if (__builtin_object_size (&x.a[0].a, 0) != sizeof (x))
    abort ();
  if (__builtin_object_size (&x.a[0].a[0], 0) != sizeof (x))
    abort ();
  if (__builtin_object_size (&x.a[0].a[3], 0) != sizeof (x) - 3)
    abort ();
  if (__builtin_object_size (&x.a[0].b, 0)
      != sizeof (x) - __builtin_offsetof (struct A, b))
    abort ();
  if (__builtin_object_size (&x.a[1].c, 0)
      != sizeof (x) - sizeof (struct A) - __builtin_offsetof (struct A, c))
    abort ();
  if (__builtin_object_size (&x.a[1].c[0], 0)
      != sizeof (x) - sizeof (struct A) - __builtin_offsetof (struct A, c))
    abort ();
  if (__builtin_object_size (&x.a[1].c[3], 0)
      != sizeof (x) - sizeof (struct A) - __builtin_offsetof (struct A, c) - 3)
    abort ();
  if (__builtin_object_size (&x.b, 0)
      != sizeof (x) - __builtin_offsetof (struct B, b))
    abort ();
  if (__builtin_object_size (&x.b.a, 0)
      != sizeof (x) - __builtin_offsetof (struct B, b))
    abort ();
  if (__builtin_object_size (&x.b.a[0], 0)
      != sizeof (x) - __builtin_offsetof (struct B, b))
    abort ();
  if (__builtin_object_size (&x.b.a[3], 0)
      != sizeof (x) - __builtin_offsetof (struct B, b) - 3)
    abort ();
  if (__builtin_object_size (&x.b.b, 0)
      != sizeof (x) - __builtin_offsetof (struct B, b)
	 - __builtin_offsetof (struct A, b))
    abort ();
  if (__builtin_object_size (&x.b.c, 0)
      != sizeof (x) - __builtin_offsetof (struct B, b)
	 - __builtin_offsetof (struct A, c))
    abort ();
  if (__builtin_object_size (&x.b.c[0], 0)
      != sizeof (x) - __builtin_offsetof (struct B, b)
	 - __builtin_offsetof (struct A, c))
    abort ();
  if (__builtin_object_size (&x.b.c[3], 0)
      != sizeof (x) - __builtin_offsetof (struct B, b)
	 - __builtin_offsetof (struct A, c) - 3)
    abort ();
  if (__builtin_object_size (&x.c, 0)
      != sizeof (x) - __builtin_offsetof (struct B, c))
    abort ();
  if (__builtin_object_size (&x.c[0], 0)
      != sizeof (x) - __builtin_offsetof (struct B, c))
    abort ();
  if (__builtin_object_size (&x.c[1], 0)
      != sizeof (x) - __builtin_offsetof (struct B, c) - 1)
    abort ();
  if (__builtin_object_size (&x.d, 0)
      != sizeof (x) - __builtin_offsetof (struct B, d))
    abort ();
  if (__builtin_object_size (&x.e, 0)
      != sizeof (x) - __builtin_offsetof (struct B, e))
    abort ();
  if (__builtin_object_size (&x.f, 0)
      != sizeof (x) - __builtin_offsetof (struct B, f))
    abort ();
  dp = &__real__ x.f;
  if (__builtin_object_size (dp, 0)
      != sizeof (x) - __builtin_offsetof (struct B, f))
    abort ();
  dp = &__imag__ x.f;
  if (__builtin_object_size (dp, 0)
      != sizeof (x) - __builtin_offsetof (struct B, f)
	 - sizeof (x.f) / 2)
    abort ();
  dp = &y;
  if (__builtin_object_size (dp, 0) != sizeof (y))
    abort ();
  if (__builtin_object_size (&z, 0) != sizeof (z))
    abort ();
  dp = &__real__ z;
  if (__builtin_object_size (dp, 0) != sizeof (z))
    abort ();
  dp = &__imag__ z;
  if (__builtin_object_size (dp, 0) != sizeof (z) / 2)
    abort ();
}

struct S { unsigned int a; };

char *
__attribute__ ((noinline))
test4 (char *x, int y)
{
  register int i;
  struct A *p;

  for (i = 0; i < y; i++)
    {
      p = (struct A *) x;
      x = (char *) &p[1];
      if (__builtin_object_size (p, 0) != (size_t) -1)
	abort ();
    }
  return x;
}

void
__attribute__ ((noinline))
test5 (size_t x)
{
  char buf[64];
  char *p = &buf[8];
  size_t i;

  for (i = 0; i < x; ++i)
    p = p + 4;
  /* My understanding of ISO C99 6.5.6 is that a conforming
     program will not end up with p equal to &buf[0]
     through &buf[7], i.e. calling this function with say
     UINTPTR_MAX / 4 results in undefined behaviour.
     If that's true, then the maximum number of remaining
     bytes from p until end of the object is 56, otherwise
     it would be 64 (or conservative (size_t) -1 == unknown).  */
  if (__builtin_object_size (p, 0) != sizeof (buf) - 8)
    abort ();
  memset (p, ' ', sizeof (buf) - 8 - 4 * 4);
}

void
__attribute__ ((noinline))
test6 (size_t x)
{
  struct T { char buf[64]; char buf2[64]; } t;
  char *p = &t.buf[8];
  size_t i;

  for (i = 0; i < x; ++i)
    p = p + 4;
  if (__builtin_object_size (p, 0) != sizeof (t) - 8)
    abort ();
  memset (p, ' ', sizeof (t) - 8 - 4 * 4);
}

void
__attribute__ ((noinline))
test7 (void)
{
  char buf[64];
  struct T { char buf[64]; char buf2[64]; } t;
  char *p = &buf[64], *q = &t.buf[64];

  if (__builtin_object_size (p + 64, 0) != 0)
    abort ();
  if (__builtin_object_size (q + 63, 0) != sizeof (t) - 64 - 63)
    abort ();
  if (__builtin_object_size (q + 64, 0) != sizeof (t) - 64 - 64)
    abort ();
  if (__builtin_object_size (q + 256, 0) != 0)
    abort ();
}

void
__attribute__ ((noinline))
test8 (void)
{
  struct T { char buf[10]; char buf2[10]; } t;
  char *p = &t.buf2[-4];
  char *q = &t.buf2[0];
  if (__builtin_object_size (p, 0) != sizeof (t) - 10 + 4)
    abort ();
  if (__builtin_object_size (q, 0) != sizeof (t) - 10)
    abort ();
  /* GCC only handles additions, not subtractions.  */
  q = q - 8;
  if (__builtin_object_size (q, 0) != (size_t) -1
      && __builtin_object_size (q, 0) != sizeof (t) - 10 + 8)
    abort ();
  p = &t.buf[-4];
  if (__builtin_object_size (p, 0) != 0)
    abort ();
}

int
main (void)
{
  struct S s[10];
  __asm ("" : "=r" (l1) : "0" (l1));
  test1 (main, 6);
  test2 ();
  test3 ();
  test4 ((char *) s, 10);
  test5 (4);
  test6 (4);
  test7 ();
  test8 ();
  exit (0);
}