/* add_expr
* : mul_expr
* | add_expr ADD mul_expr
* | add_expr SUB mul_expr
*/
static void add_expr(ApexParser *parser) {
mul_expr(parser);
for (;;) {
ApexAstNode *left, *right;
ApexAstOpr opr;
if (accept(parser, '+')) {
opr = '+';
} else if (accept(parser, '-')) {
opr = '-';
} else {
break;
}
left = apex_ast_pop(parser->ast);
mul_expr(parser);
right = apex_ast_pop(parser->ast);
apex_ast_opr2(parser->ast, opr, left, right);
}
}
static void
add_expr(void)
{
switch(token.type) {
case TOKEN_INTEGER:
case TOKEN_LPARENTH:
mul_expr();
if (err == SYN_ERR) {
goto out;
}
rest_add_expr();
goto out;
default:
err = SYN_ERR;
goto out;
}
out:
return ;
}
static void
rest_add_expr(void)
{
number op1, op2;
unsigned int tmp, rv, i;
while (token.type == TOKEN_PLUS || token.type == TOKEN_MINUS) {
tmp = token.type;
get_next_token();
mul_expr();
if (err == SYN_ERR) {
goto out;
}
rv = pop_item(&sp, &op2);
if (rv != OK) {
err = MEM_ERR;
goto out;
}
rv = pop_item(&sp, &op1);
if (rv != OK) {
err = MEM_ERR;
goto out;
}
if (op1.frac == op2.frac)
goto main_part;
if (op1.frac > op2.frac) {
for (i = 0; i < (op1.frac - op2.frac); i++)
rv = mpl_mul_dig(&op2.value, &op2.value, 10);
if (rv != MPL_OK) {
err = MEM_ERR;
goto out;
}
op2.frac = op1.frac;
} else {
for (i = 0; i < (op2.frac - op1.frac); i++)
rv = mpl_mul_dig(&op1.value, &op1.value, 10);
if (rv != MPL_OK) {
err = MEM_ERR;
goto out;
}
op1.frac = op2.frac;
}
main_part:
if (tmp == TOKEN_PLUS) {
rv = mpl_add(&op1.value, &op1.value, &op2.value);
if (rv != MPL_OK) {
err = MEM_ERR;
goto out;
}
} else if (tmp == TOKEN_MINUS) {
rv = mpl_sub(&op1.value, &op1.value, &op2.value);
if (rv != MPL_OK) {
err = MEM_ERR;
goto out;
}
}
rv = push_item(&sp, &op1);
if (rv != OK) {
err = MEM_ERR;
goto out;
}
mpl_clear(&op2.value);
}
if (token.type != TOKEN_EOL && token.type != TOKEN_RPARENTH) {
err = SYN_ERR;
goto out;
}
out:
return ;
}
void eval_expr(expr *in, expr *out, symtab *table)
{
switch (in->type) {
case NOTHING: break;
case INTEGER: case REAL: case STRING:
out->type = in->type;
out->val = in->val;
return;
case INT_VAR: {
int n;
if (lookup_int(in->val.string, table, &n)) {
out->type = INTEGER;
out->val.integer = n;
return;
} else {
fprintf(stderr, "undefined integer variable '%s'\n",
in->val.string);
exit(1);
}
} break;
case REAL_VAR: {
double d;
if (lookup_real(in->val.string, table, &d)) {
out->type = REAL;
out->val.real = d;
return;
} else {
fprintf(stderr, "undefined real variable '%s'\n",
in->val.string);
exit(1);
}
} break;
case STR_VAR: {
char *s = (char *)malloc(MAX_LINE);
if (lookup_str(in->val.string, table, &s)) {
out->type = STRING;
out->val.string = s;
return;
} else {
fprintf(stderr, "undefined string variable '%s'\n",
in->val.string);
exit(1);
}
} break;
}
switch (in->op) {
case NOTHING:
fprintf(stderr, "No operation for non-constant expression\n");
exit(1);
case ADD:
add_expr(in, out, table);
break;
case SUB:
sub_expr(in, out, table);
break;
case EXPT:
pow_expr(in, out, table);
break;
case MUL:
mul_expr(in, out, table);
break;
case DIV:
div_expr(in, out, table);
break;
case LT:
eval_expr(in->arg1, out->arg1, table);
eval_expr(in->arg2, out->arg2, table);
out->type = INTEGER;
out->val.integer = compare(out->arg1, out->arg2, LT);
break;
case LE:
eval_expr(in->arg1, out->arg1, table);
eval_expr(in->arg2, out->arg2, table);
out->type = INTEGER;
out->val.integer = compare(out->arg1, out->arg2, LE);
break;
case EQ:
eval_expr(in->arg1, out->arg1, table);
eval_expr(in->arg2, out->arg2, table);
out->type = INTEGER;
out->val.integer = compare(out->arg1, out->arg2, EQ);
break;
case GE:
eval_expr(in->arg1, out->arg1, table);
eval_expr(in->arg2, out->arg2, table);
out->type = INTEGER;
out->val.integer = compare(out->arg1, out->arg2, GE);
break;
case GT:
eval_expr(in->arg1, out->arg1, table);
eval_expr(in->arg2, out->arg2, table);
out->type = INTEGER;
out->val.integer = compare(out->arg1, out->arg2, GT);
break;
case NE:
eval_expr(in->arg1, out->arg1, table);
eval_expr(in->arg2, out->arg2, table);
out->type = INTEGER;
out->val.integer = compare(out->arg1, out->arg2, NE);
break;
/* Numerical functions */
case RAND: {
expr arg;
eval_expr(in->arg1, &arg, table);
out->type = INTEGER;
out->val.integer = rand() % arg.val.integer;
} break;
case SQRT: {
expr arg;
eval_expr(in->arg1, &arg, table);
out->type = REAL;
out->val.real = sqrt(arg.type == REAL ? arg.val.real :
(double)arg.val.integer);
} break;
/* Casting */
case CEIL: {
expr arg;
eval_expr(in->arg1, &arg, table);
out->type = INTEGER;
out->val.integer = (int)ceil(arg.val.real);
} break;
case FLOOR: {
expr arg;
eval_expr(in->arg1, &arg, table);
out->type = INTEGER;
out->val.integer = (int)floor(arg.val.real);
} break;
case REAL_CAST: {
expr arg;
eval_expr(in->arg1, &arg, table);
out->type = REAL;
out->val.real = (double)arg.val.integer;
} break;
case ROUND: {
expr arg;
eval_expr(in->arg1, &arg, table);
out->type = INTEGER;
out->val.integer = (int)round(arg.val.real);
} break;
default:
fprintf(stderr, "unrecognised operation\n");
exit(1);
}
}
