/* reconhece e traduz uma expressão */
int expression(){
int val;
if (isAddOp(look))
val = 0;
else
val = term();
while (isAddOp(look)) {
switch (look) {
case '+':
match('+');
val += term();
break;
case '-':
match('-');
val -= term();
break;
}
}
}
/* reconhece e traduz uma expressão */
void expression(){
if(isAddOp(look)){
emit("XOR AX, AX");
}else{
term();
}
while(look == '+' || look == '-'){
emit("PUSH AX");
switch(look) {
case '+':
add();
break;
case '-':
subtract();
break;
default:
break;
}
}
}
int expression()
{
int result;
result = term();
while (isAddOp(*p))
{
switch(*p)
{
case '-':
match('-');
result = result - term();
break;
case '+':
match('+');
result = result + term();
break;
}
}
return result;
}
int getNumber()
{
int result = 0, value = 1;
if( isAddOp(*p))
{
if(*p == '-')
{
value = -1;
}
p++;
}
if (isdigit (*p))
{
while(isdigit(*p))
{
result = result * 10 + (*p - '0');
p++;
}
}
else
{
printf("Error: expected digit\n");
exit(EXIT_FAILURE);
}
result = result * value;
return result;
}
/* analisa e traduz um termo */
int term()
{
int val;
val = factor();
while (isAddOp(look)) {
switch (look) {
case '*':
match('*');
val *= factor();
break;
case '/':
match('/');
val /= factor();
break;
}
}
return val;
}
void SimplExpr() {
/*
SimplExpr -> [ + | - ] term { addop term }
*/
if ( debugMode) printf( "In SimplExpr\n");
if ( sym == plus || sym == hyphen)
{
writesym();
nextsym();
}
term();
while ( isAddOp( sym))
{
nextsym();
term();
}
if ( debugMode) printf( "Out SimplExpr\n");
}
/* Parse and Translate an Expression */
TreeNode* Parser::Expression()
{
TreeNode* retExp = Term(); // preset the base-TreeNode as it eventually will be returned
TreeNode* pos = retExp;
TreeNode* left = NULL;
TreeNode* right = NULL;
while ( isAddOp(currentToken) )
{
left = pos;
pos = new TreeNode(currentToken, Unknown);
pos->appendChild(left);
switch (currentToken.type)
{
case tokPlus:
matchToken(tokPlus);
right = Term();
pos->setType(addNode);
break;
case tokMinus:
matchToken(tokMinus);
right = Term();
pos->setType(subNode);
break;
case tokGt:
matchToken(tokGt);
right = Term();
pos->setType(nodeGT);
break;
case tokLt:
matchToken(tokLt);
right = Term();
pos->setType(nodeLT);
break;
case tokGe:
matchToken(tokGe);
right = Term();
pos->setType(nodeGE);
break;
case tokLe:
matchToken(tokLe);
right = Term();
pos->setType(nodeLE);
break;
case tokEq:
matchToken(tokEq);
right = Term();
pos->setType(nodeEQ);
break;
case tokNe:
matchToken(tokNe);
right = Term();
pos->setType(nodeNE);
break;
case tokOr:
matchToken(tokOr);
right = Term();
pos->setType(orNode);
break;
default:
Error(currentToken, i18n("Expected '*' or '/'"), 1040);
getToken();
return pos;
break;
}
if (right != NULL) pos->appendChild(right);
retExp = pos;
}
return retExp;
}
