gdb/testsuite/gdb.base/range-stepping.c

/* This testcase is part of GDB, the GNU debugger.

   Copyright 2013-2021 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

/* Note: 'volatile' is used to make sure the compiler doesn't fold /
   optimize out the arithmetic that uses the variables.  */

static int
func1 (int a, int b)
{
  volatile int r = a * b;

  r += (a | b);
  r += (a - b);

  return r;
}

int
main(void)
{
  volatile int a = 0;
  volatile int b = 1;
  volatile int c = 2;
  volatile int d = 3;
  volatile int e = 4;
  volatile double d1 = 1.0;
  volatile double d2 = 2.0;

  /* A macro that expands to a single source line that compiles to a
     number of instructions, with no branches.  */
#define LINE_WITH_MULTIPLE_INSTRUCTIONS		\
  do							\
    {							\
      a = b + c + d * e - a;				\
    } while (0)

  LINE_WITH_MULTIPLE_INSTRUCTIONS; /* location 1 */

  /* A line of source code that compiles to a function call (jump or
     branch), surrounded by instructions before and after.  IOW, this
     will generate approximately the following pseudo-instructions:

addr1:
     insn1;
     insn2;
     ...
     call func1;
     ...
     insn3;
addr2:
     insn4;
*/
  e = 10 + func1 (a + b, c * d); /* location 2 */

  e = 10 + func1 (a + b, c * d);

  /* Generate a single source line that includes a short loop.  */
#define LINE_WITH_LOOP						\
  do								\
    {								\
      for (a = 0, e = 0; a < 15; a++)				\
	e += a;							\
    } while (0)

  LINE_WITH_LOOP;

  LINE_WITH_LOOP;

  /* Generate a single source line that includes a time-consuming
     loop.  GDB breaks the loop early by clearing variable 'c'.  */
#define LINE_WITH_TIME_CONSUMING_LOOP					\
  do									\
    {									\
      for (c = 1, a = 0; a < 65535 && c; a++)				\
	for (b = 0; b < 65535 && c; b++)				\
	  {								\
	    d1 = d2 * a / b;						\
	    d2 = d1 * a;						\
	  }								\
    } while (0)

  LINE_WITH_TIME_CONSUMING_LOOP;

  /* Some multi-instruction lines for software watchpoint tests.  */
  LINE_WITH_MULTIPLE_INSTRUCTIONS;
  LINE_WITH_MULTIPLE_INSTRUCTIONS; /* soft-watch */
  LINE_WITH_MULTIPLE_INSTRUCTIONS;

  return 0;
}