Function evalStandardFunc

src/bin/pgbench/pgbench.c:2068–2635

* Recursive evaluation of standard functions, * which do not require lazy evaluation. */

 * which do not require lazy evaluation.
 */
static bool
evalStandardFunc(CState *st,
				 PgBenchFunction func, PgBenchExprLink *args,
				 PgBenchValue *retval)
{
	/* evaluate all function arguments */
	int			nargs = 0;
	PgBenchValue vargs[MAX_FARGS];
	PgBenchExprLink *l = args;
	bool		has_null = false;

	/* Some compiler (gcc-12) may raise warning about uninitialized variable */
	memset(vargs, 0, sizeof(vargs));

	for (nargs = 0; nargs < MAX_FARGS && l != NULL; nargs++, l = l->next)
	{
		if (!evaluateExpr(st, l->expr, &vargs[nargs]))
			return false;
		has_null |= vargs[nargs].type == PGBT_NULL;
	}

	if (l != NULL)
	{
		pg_log_error("too many function arguments, maximum is %d", MAX_FARGS);
		return false;
	}

	/* NULL arguments */
	if (has_null && func != PGBENCH_IS && func != PGBENCH_DEBUG)
	{
		setNullValue(retval);
		return true;
	}

	/* then evaluate function */
	switch (func)
	{
			/* overloaded operators */
		case PGBENCH_ADD:
		case PGBENCH_SUB:
		case PGBENCH_MUL:
		case PGBENCH_DIV:
		case PGBENCH_MOD:
		case PGBENCH_EQ:
		case PGBENCH_NE:
		case PGBENCH_LE:
		case PGBENCH_LT:
			{
				PgBenchValue *lval = &vargs[0],
						   *rval = &vargs[1];

				Assert(nargs == 2);

				/* overloaded type management, double if some double */
				if ((lval->type == PGBT_DOUBLE ||
					 rval->type == PGBT_DOUBLE) && func != PGBENCH_MOD)
				{
					double		ld,