loop-7.c

来自「Mac OS X 10.4.9 for x86 Source Code gcc」· C语言 代码 · 共 35 行

/* PR tree-optimization/19828 */
/* { dg-do compile } */
/* { dg-options "-O1 -fdump-tree-lim-details" } */

int cst_fun1 (int) __attribute__((__const__));
int cst_fun2 (int) __attribute__((__const__));
int pure_fun1 (int) __attribute__((__pure__));
int pure_fun2 (int) __attribute__((__pure__));
int foo (void);

int xxx (void)
{
  int i, k = foo (), x = 0;

  for (i = 0; i < 100; i++)
    {
      x += cst_fun1 (k);
      x += pure_fun1 (k);

      if (k)
	{
	  x += cst_fun2 (k);
	  x += pure_fun2 (k);
	}
    }

  return x;
}

/* Calls to cst_fun1 and pure_fun1 may be moved out of the loop.
   Calls to cst_fun2 and pure_fun2 should not be, since calling
   with k = 0 may be invalid.  */

/* { dg-final { scan-tree-dump-times "Moving statement" 2 "lim" } } */