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* [Bug tree-optimization/64878] New: [5 Regression] Miscompilation of nntpgrab
@ 2015-01-30 17:29 jakub at gcc dot gnu.org
  2015-01-30 17:29 ` [Bug tree-optimization/64878] " jakub at gcc dot gnu.org
                   ` (10 more replies)
  0 siblings, 11 replies; 12+ messages in thread
From: jakub at gcc dot gnu.org @ 2015-01-30 17:29 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64878

            Bug ID: 64878
           Summary: [5 Regression] Miscompilation of nntpgrab
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jakub at gcc dot gnu.org

Starting with r218451 gcc miscompiles at -O2 on x86_64-linux (both -m64 and
-m32) following testcase:

struct A { int a1; };
struct B { char *b1; int b2; int b3; };
struct C { char *c1; int c2; struct B *c3; };
extern struct A *f1 (char *s);
static struct A *f2 (struct C *x);
__attribute__ ((noinline, noclone)) int f3 (struct A *x, struct A *z) { asm
volatile ("" : : "g" (x), "g" (z) : "memory"); return 0; }
__attribute__ ((noinline, noclone)) void f4 (struct A *x, char *y, struct A *z)
{ asm volatile ("" : : "g" (x), "g" (z), "g" (y) : "memory"); }
__attribute__ ((noinline, noclone)) struct B *f5 (void) { static char b[32];
static struct B f3 = { b, 0, 32 }; return &f3; }
__attribute__ ((noinline, noclone)) int f6 (struct B *p, char *w, int z) { asm
volatile ("" : : "g" (p), "g" (w), "g" (z) : "memory"); return 0; }
__attribute__ ((noinline, noclone)) void f7 (struct B *p) { asm volatile ("" :
: "g" (p) : "memory"); }
__attribute__ ((noinline, noclone)) void f8 (struct B *p) { asm volatile ("" :
: "g" (p) : "memory"); }
__attribute__ ((noinline, noclone)) void f9 (struct A *x) { asm volatile ("" :
: "g" (x) : "memory"); }
__attribute__ ((noinline, noclone)) struct A *f10 (void) { static struct A j;
asm volatile ("" : :  : "memory"); return &j; }
__attribute__ ((noinline, noclone)) struct A *f11 (void) { static struct A j;
asm volatile ("" : :  : "memory"); return &j; }
__attribute__ ((noinline, noclone)) struct A *f12 (int b) { static struct A j;
asm volatile ("" : : "g" (b) : "memory"); return &j; }
__attribute__ ((noinline, noclone)) struct A *f13 (int i) { static struct A j;
asm volatile ("" : : "g" (i) : "memory"); return &j; }
__attribute__ ((noinline, noclone)) struct A *f14 (double d) { static struct A
j; asm volatile ("" : : "g" (&d) : "memory"); return &j; }
__attribute__ ((noinline, noclone)) struct A *f15 (char *s) { static struct A
j; asm volatile ("" : : "g" (s) : "memory"); return &j; }
char *t = "0123456789abcdef";
char *u = "0123456789.+-e";

__attribute__ ((noinline, noclone)) struct A *
f1 (char *s)
{
  struct C f;
  struct A *o;
  f.c1 = s;
  f.c2 = 0;
  f.c3 = f5 ();
  o = f2 (&f);
  f8 (f.c3);
  return o;
}

static struct A *
f2 (struct C *x)
{
  int a, b, e = 0;
  struct A *f = 0, *o;
  char *g = 0;
  char h = '\0';
  int i = 0, j = 0;
  a = 0;
  b = 1;
  char c;
  do
    {
      c = x->c1[x->c2];
      switch (a)
    {
    case 0:
      if (c == ' ')
        x->c2++;
      else if (c == '/')
        {
          a = 4;
          j = x->c2++;
        }
      else
        a = b;
      break;
    case 1:
      switch (c)
        {
        case '{':
          a = 0;
          b = 15;
          f = f10 ();
          x->c2++;
          break;
        case '[':
          a = 0;
          b = 13;
          f = f11 ();
          x->c2++;
          break;
        case 'N':
        case 'n':
          a = 3;
          j = x->c2++;
          break;
        case '"':
        case '\'':
          h = c;
          f7 (x->c3);
          a = 8;
          j = ++x->c2;
          break;
        case 'T':
        case 't':
        case 'F':
        case 'f':
          a = 11;
          j = x->c2++;
          break;
        case '0' ... '9':
        case '-':
          i = 0;
          a = 12;
          j = x->c2++;
          break;
        default:
          e = 1;
          goto out;
        }
      break;
    case 2:
      goto out;
    case 3:
      if (__builtin_strncmp ("null", x->c1 + j, x->c2 - j))
        {
          e = 2;
          goto out;
        }
      if (x->c2 - j == 4)
        {
          f = 0;
          b = 2;
          a = 0;
        }
      else
        x->c2++;
      break;
    case 4:
      if (c == '*')
        a = 5;
      else if (c == '/')
        a = 6;
      else
        {
          e = 8;
          goto out;
        }
      x->c2++;
      break;
    case 5:
      if (c == '*')
        a = 7;
      x->c2++;
      break;
    case 6:
      if (c == '\n')
        a = 0;
      x->c2++;
      break;
    case 7:
      if (c == '/')
        a = 0;
      else
        a = 5;
      x->c2++;
      break;
    case 8:
      if (c == h)
        {
          f6 (x->c3, x->c1 + j, x->c2 - j);
          f = f15 (x->c3->b1);
          b = 2;
          a = 0;
        }
      else if (c == '\\')
        {
          b = 8;
          a = 9;
        }
      x->c2++;
      break;
    case 9:
      switch (c)
        {
        case '"':
        case '\\':
          f6 (x->c3, x->c1 + j, x->c2 - j - 1);
          j = x->c2++;
          a = b;
          break;
        case 'b':
        case 'n':
        case 'r':
        case 't':
          f6 (x->c3, x->c1 + j, x->c2 - j - 1);
          if (c == 'b')
        f6 (x->c3, "\b", 1);
          else if (c == 'n')
        f6 (x->c3, "\n", 1);
          else if (c == 'r')
        f6 (x->c3, "\r", 1);
          else if (c == 't')
        f6 (x->c3, "\t", 1);
          j = ++x->c2;
          a = b;
          break;
        case 'u':
          f6 (x->c3, x->c1 + j, x->c2 - j - 1);
          j = ++x->c2;
          a = 10;
          break;
        default:
          e = 7;
          goto out;
        }
      break;
    case 10:
      if (__builtin_strchr (t, c))
        {
          x->c2++;
          if (x->c2 - j == 4)
        {
          unsigned char w[3];
          unsigned int s =
            (((x->c1[j] <= '9') ? x->c1[j] - '0' : (x->c1[j] & 7) + 9) << 12)
            + (((x->c1[j + 1] <= '9') ? x->c1[j + 1] - '0' : (x->c1[j + 1] & 7)
+ 9) << 8)
            + (((x->c1[j + 2] <= '9') ? x->c1[j + 2] - '0' : (x->c1[j + 2] & 7)
+ 9) << 4)
            + ((x->c1[j + 3] <= '9') ? x->c1[j + 3] - '0' : (x->c1[j + 3] & 7)
+ 9);
          if (s < 0x80)
            {
              w[0] = s;
              f6 (x->c3, (char *) w, 1);
            }
          else if (s < 0x800)
            {
              w[0] = 0xc0 | (s >> 6);
              w[1] = 0x80 | (s & 0x3f);
              f6 (x->c3, (char *) w, 2);
            }
          else
            {
              w[0] = 0x0 | (s >> 12);
              w[1] = 0x80 | ((s >> 6) & 0x3f);
              w[2] = 0x80 | (s & 0x3f);
              f6 (x->c3, (char *) w, 3);
            }
          j = x->c2;
          a = b;
        }
        }
      else
        {
          e = 7;
          goto out;
        }
      break;
    case 11:
      if (__builtin_strncmp ("true", x->c1 + j, x->c2 - j) == 0)
        {
          if (x->c2 - j == 4)
        {
          f = f12 (1);
          b = 2;
          a = 0;
        }
          else
        x->c2++;
        }
      else if (__builtin_strncmp ("false", x->c1 + j, x->c2 - j) == 0)
        {
          if (x->c2 - j == 5)
        {
          f = f12 (0);
          b = 2;
          a = 0;
        }
          else
        x->c2++;
        }
      else
        {
          e = 3;
          goto out;
        }
      break;
    case 12:
      if (!c || !__builtin_strchr (u, c))
        {
          if (!i)
        f = f13 (0);
          else
        f = f14 (0.0);
          b = 2;
          a = 0;
        }
      else
        {
          if (c == '.' || c == 'e')
        i = 1;
          x->c2++;
        }
      break;
    case 13:
      if (c == ']')
        {
          x->c2++;
          b = 2;
          a = 0;
        }
      else
        {
          o = f2 (x);
          if (((unsigned long) o > (unsigned long) -4000L))
        {
          e = 5;
          goto out;
        }
          f3 (f, o);
          b = 14;
          a = 0;
        }
      break;
    case 14:
      if (c == ']')
        {
          x->c2++;
          b = 2;
          a = 0;
        }
      else if (c == ',')
        {
          x->c2++;
          b = 13;
          a = 0;
        }
      else
        {
          f9 (f);
          e = 5;
          goto out;
        }
      break;
    case 15:
      a = 16;
      j = x->c2;
      break;
    case 16:
      if (c == '}')
        {
          x->c2++;
          b = 2;
          a = 0;
        }
      else if (c == '"' || c == '\'')
        {
          h = c;
          f7 (x->c3);
          a = 17;
          j = ++x->c2;
        }
      else
        {
          e = 6;
          goto out;
        }
      break;
    case 17:
      if (c == h)
        {
          f6 (x->c3, x->c1 + j, x->c2 - j);
          g = __builtin_strdup (x->c3->b1);
          b = 18;
          a = 0;
        }
      else if (c == '\\')
        {
          b = 17;
          a = 9;
        }
      x->c2++;
      break;
    case 18:
      if (c == ':')
        {
          x->c2++;
          b = 19;
          a = 0;
        }
      else
        {
          e = -6;
          goto out;
        }
      break;
    case 19:
      o = f2 (x);
      if (((unsigned long) o > (unsigned long) -4000L))
        {
          e = 6;
          goto out;
        }
      f4 (f, g, o);
      __builtin_free (g);
      g = 0;
      b = 20;
      a = 0;
      break;
    case 20:
      if (c == '}')
        {
          x->c2++;
          b = 2;
          a = 0;
        }
      else if (c == ',')
        {
          x->c2++;
          b = 15;
          a = 0;
        }
      else
        {
          e = 6;
          goto out;
        }
      break;
    }
    }
  while (c);
  if (a != 2 && b != 2)
    e = 9;
out:
  __builtin_free (g);
  if (e == 0)
    return f;
  f9 (f);
  return 0;
}

int
main ()
{
  asm volatile ("" : : : "memory");
  struct A *r = f1 ("{ \"id\": null, \"blahah\": \"foobarbazbar\", \"barbar\":
{ \"barbarbarba\":"
            "\"abcdefgh\", \"ijklmnopqr\": \"stuvwxyzabcdefghijklmnopqrstuv\",
\"xyzxyz\":"
            " [ \"1\" ] } }");
  if (!r)
    __builtin_abort ();
  return 0;
}


^ permalink raw reply	[flat|nested] 12+ messages in thread
end of thread, other threads:[~2015-03-05 14:28 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-01-30 17:29 [Bug tree-optimization/64878] New: [5 Regression] Miscompilation of nntpgrab jakub at gcc dot gnu.org
2015-01-30 17:29 ` [Bug tree-optimization/64878] " jakub at gcc dot gnu.org
2015-01-30 17:30 ` jakub at gcc dot gnu.org
2015-01-30 20:15 ` spop at gcc dot gnu.org
2015-01-30 20:19 ` spop at gcc dot gnu.org
2015-01-30 20:27 ` spop at gcc dot gnu.org
2015-02-02 17:25 ` spop at gcc dot gnu.org
2015-02-04 17:30 ` spop at gcc dot gnu.org
2015-02-04 17:41 ` jakub at gcc dot gnu.org
2015-02-06 21:08 ` spop at gcc dot gnu.org
2015-02-06 21:16 ` jakub at gcc dot gnu.org
2015-03-05 14:28 ` yroux at gcc dot gnu.org

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