Function set_stack_base

src/backend/tcop/postgres.c:4398–4428

* set_stack_base: set up reference point for stack depth checking * * Returns the old reference point, if any. */

 * Returns the old reference point, if any.
 */
pg_stack_base_t
set_stack_base(void)
{
#ifndef HAVE__BUILTIN_FRAME_ADDRESS
	char		stack_base;
#endif
	pg_stack_base_t old;

#if defined(__ia64__) || defined(__ia64)
	old.stack_base_ptr = stack_base_ptr;
	old.register_stack_base_ptr = register_stack_base_ptr;
#else
	old = stack_base_ptr;
#endif

	/*
	 * Set up reference point for stack depth checking.  On recent gcc we use
	 * __builtin_frame_address() to avoid a warning about storing a local
	 * variable's address in a long-lived variable.
	 */
#ifdef HAVE__BUILTIN_FRAME_ADDRESS
	stack_base_ptr = __builtin_frame_address(0);
#else
	stack_base_ptr = &stack_base;
#endif
#if defined(__ia64__) || defined(__ia64)
	register_stack_base_ptr = ia64_get_bsp();
#endif

	return old;
}

/*
 * restore_stack_base: restore reference point for stack depth checking