static void ReturnStatement (void)
/* Handle the 'return' statement */
{
ExprDesc Expr;
NextToken ();
if (CurTok.Tok != TOK_SEMI) {
/* Evaluate the return expression */
hie0 (&Expr);
/* If we return something in a void function, print an error and
** ignore the value. Otherwise convert the value to the type of the
** return.
*/
if (F_HasVoidReturn (CurrentFunc)) {
Error ("Returning a value in function with return type void");
} else {
/* Convert the return value to the type of the function result */
TypeConversion (&Expr, F_GetReturnType (CurrentFunc));
/* Load the value into the primary */
LoadExpr (CF_NONE, &Expr);
}
} else if (!F_HasVoidReturn (CurrentFunc) && !F_HasOldStyleIntRet (CurrentFunc)) {
Error ("Function `%s' must return a value", F_GetFuncName (CurrentFunc));
}
/* Mark the function as having a return statement */
F_ReturnFound (CurrentFunc);
/* Cleanup the stack in case we're inside a block with locals */
g_space (StackPtr - F_GetTopLevelSP (CurrentFunc));
/* Output a jump to the function exit code */
g_jump (F_GetRetLab (CurrentFunc));
}
void NextToken (void)
/* Get next token from input stream */
{
ident token;
/* We have to skip white space here before shifting tokens, since the
** tokens and the current line info is invalid at startup and will get
** initialized by reading the first time from the file. Remember if
** we were at end of input and handle that later.
*/
int GotEOF = (SkipWhite() == 0);
/* Current token is the lookahead token */
if (CurTok.LI) {
ReleaseLineInfo (CurTok.LI);
}
CurTok = NextTok;
/* When reading the first time from the file, the line info in NextTok,
** which was copied to CurTok is invalid. Since the information from
** the token is used for error messages, we must make it valid.
*/
if (CurTok.LI == 0) {
CurTok.LI = UseLineInfo (GetCurLineInfo ());
}
/* Remember the starting position of the next token */
NextTok.LI = UseLineInfo (GetCurLineInfo ());
/* Now handle end of input. */
if (GotEOF) {
/* End of file reached */
NextTok.Tok = TOK_CEOF;
return;
}
/* Determine the next token from the lookahead */
if (IsDigit (CurC) || (CurC == '.' && IsDigit (NextC))) {
/* A number */
NumericConst ();
return;
}
/* Check for wide character literals */
if (CurC == 'L' && NextC == '\"') {
StringConst ();
return;
}
/* Check for keywords and identifiers */
if (IsSym (token)) {
/* Check for a keyword */
if ((NextTok.Tok = FindKey (token)) != TOK_IDENT) {
/* Reserved word found */
return;
}
/* No reserved word, check for special symbols */
if (token[0] == '_' && token[1] == '_') {
/* Special symbols */
if (strcmp (token+2, "FILE__") == 0) {
NextTok.SVal = AddLiteral (GetCurrentFile());
NextTok.Tok = TOK_SCONST;
return;
} else if (strcmp (token+2, "LINE__") == 0) {
NextTok.Tok = TOK_ICONST;
NextTok.IVal = GetCurrentLine();
NextTok.Type = type_int;
return;
} else if (strcmp (token+2, "func__") == 0) {
/* __func__ is only defined in functions */
if (CurrentFunc) {
NextTok.SVal = AddLiteral (F_GetFuncName (CurrentFunc));
NextTok.Tok = TOK_SCONST;
return;
}
}
}
/* No reserved word but identifier */
strcpy (NextTok.Ident, token);
NextTok.Tok = TOK_IDENT;
return;
}
/* Monstrous switch statement ahead... */
switch (CurC) {
case '!':
NextChar ();
if (CurC == '=') {
SetTok (TOK_NE);
} else {
NextTok.Tok = TOK_BOOL_NOT;
}
break;
case '\"':
StringConst ();
break;
case '%':
NextChar ();
if (CurC == '=') {
SetTok (TOK_MOD_ASSIGN);
} else {
NextTok.Tok = TOK_MOD;
}
break;
case '&':
NextChar ();
switch (CurC) {
case '&':
SetTok (TOK_BOOL_AND);
break;
case '=':
SetTok (TOK_AND_ASSIGN);
break;
default:
NextTok.Tok = TOK_AND;
}
break;
case '\'':
CharConst ();
break;
case '(':
SetTok (TOK_LPAREN);
break;
case ')':
SetTok (TOK_RPAREN);
break;
case '*':
NextChar ();
if (CurC == '=') {
SetTok (TOK_MUL_ASSIGN);
} else {
NextTok.Tok = TOK_STAR;
}
break;
case '+':
NextChar ();
switch (CurC) {
case '+':
SetTok (TOK_INC);
break;
case '=':
SetTok (TOK_PLUS_ASSIGN);
break;
default:
NextTok.Tok = TOK_PLUS;
}
break;
case ',':
SetTok (TOK_COMMA);
break;
case '-':
NextChar ();
switch (CurC) {
case '-':
SetTok (TOK_DEC);
break;
case '=':
SetTok (TOK_MINUS_ASSIGN);
break;
case '>':
SetTok (TOK_PTR_REF);
break;
default:
NextTok.Tok = TOK_MINUS;
}
break;
case '.':
NextChar ();
if (CurC == '.') {
NextChar ();
if (CurC == '.') {
SetTok (TOK_ELLIPSIS);
} else {
UnknownChar (CurC);
}
} else {
NextTok.Tok = TOK_DOT;
}
break;
case '/':
NextChar ();
if (CurC == '=') {
SetTok (TOK_DIV_ASSIGN);
} else {
NextTok.Tok = TOK_DIV;
}
break;
case ':':
SetTok (TOK_COLON);
break;
case ';':
SetTok (TOK_SEMI);
break;
case '<':
NextChar ();
switch (CurC) {
case '=':
SetTok (TOK_LE);
break;
case '<':
NextChar ();
if (CurC == '=') {
SetTok (TOK_SHL_ASSIGN);
} else {
NextTok.Tok = TOK_SHL;
}
break;
default:
NextTok.Tok = TOK_LT;
}
break;
case '=':
NextChar ();
if (CurC == '=') {
SetTok (TOK_EQ);
} else {
NextTok.Tok = TOK_ASSIGN;
}
break;
case '>':
NextChar ();
switch (CurC) {
case '=':
SetTok (TOK_GE);
break;
case '>':
NextChar ();
if (CurC == '=') {
SetTok (TOK_SHR_ASSIGN);
} else {
NextTok.Tok = TOK_SHR;
}
break;
default:
NextTok.Tok = TOK_GT;
}
break;
case '?':
SetTok (TOK_QUEST);
break;
case '[':
SetTok (TOK_LBRACK);
break;
case ']':
SetTok (TOK_RBRACK);
break;
case '^':
NextChar ();
if (CurC == '=') {
SetTok (TOK_XOR_ASSIGN);
} else {
NextTok.Tok = TOK_XOR;
}
break;
case '{':
SetTok (TOK_LCURLY);
break;
case '|':
NextChar ();
switch (CurC) {
case '|':
SetTok (TOK_BOOL_OR);
break;
case '=':
SetTok (TOK_OR_ASSIGN);
break;
default:
NextTok.Tok = TOK_OR;
}
break;
case '}':
SetTok (TOK_RCURLY);
break;
case '~':
SetTok (TOK_COMP);
break;
default:
UnknownChar (CurC);
}
}
