Ejemplo n.º 1
0
/* ParseExpr3 - handle the BXOR operator */
static ParseTreeNode *ParseExpr3(ParseContext *c)
{
    ParseTreeNode *expr, *expr2;
    int tkn;
    expr = ParseExpr4(c);
    while ((tkn = GetToken(c)) == '^') {
        expr2 = ParseExpr4(c);
        if (IsIntegerLit(expr) && IsIntegerLit(expr2))
            expr->u.integerLit.value = expr->u.integerLit.value ^ expr2->u.integerLit.value;
        else
            expr = MakeBinaryOpNode(c, OP_BXOR, expr, expr2);
    }
    SaveToken(c,tkn);
    return expr;
}
Ejemplo n.º 2
0
/* ParseArrayInitializers - parse array initializers */
static void ParseArrayInitializers(ParseContext *c, VMVALUE size)
{
    VMVALUE *dataPtr = (VMVALUE *)c->codeBuf;
    VMVALUE *dataTop = (VMVALUE *)c->ctop;
    int done = VMFALSE;
    Token tkn;

    FRequire(c, '{');

    /* handle each line of initializers */
    while (!done) {
        int lineDone = VMFALSE;

        /* look for the first non-blank line */
        while ((tkn = GetToken(c)) == T_EOL) {
            if (!GetLine(c))
                ParseError(c, "unexpected end of file in initializers");
        }

        /* check for the end of the initializers */
        if (tkn == '}')
            break;
        SaveToken(c, tkn);

        /* handle each initializer in the current line */
        while (!lineDone) {
            ParseTreeNode *expr;

            /* get a constant expression */
            expr = ParseExpr(c);
            if (!IsIntegerLit(expr))
                ParseError(c, "expecting a constant expression");

            /* check for too many initializers */
            if (--size < 0)
                ParseError(c, "too many initializers");

            /* store the initial value */
            if (dataPtr >= dataTop)
                ParseError(c, "insufficient object data space");
            *dataPtr++ = expr->u.integerLit.value;

            switch (tkn = GetToken(c)) {
            case T_EOL:
                lineDone = VMTRUE;
                break;
            case '}':
                lineDone = VMTRUE;
                done = VMTRUE;
                break;
            case ',':
                break;
            default:
                ParseError(c, "expecting a comma, right brace or end of line");
                break;
            }

        }
    }
}
Ejemplo n.º 3
0
/* ParseScalarInitializer - parse a scalar initializer */
static VMVALUE ParseScalarInitializer(ParseContext *c)
{
    ParseTreeNode *expr = ParseExpr(c);
    if (!IsIntegerLit(expr))
        ParseError(c, "expecting a constant expression");
    return expr->u.integerLit.value;
}
Ejemplo n.º 4
0
/* ParseExpr8 - handle the '<<' and '>>' operators */
static ParseTreeNode *ParseExpr8(ParseContext *c)
{
    ParseTreeNode *expr, *expr2;
    int tkn;
    expr = ParseExpr9(c);
    while ((tkn = GetToken(c)) == T_SHL || tkn == T_SHR) {
        expr2 = ParseExpr9(c);
        if (IsIntegerLit(expr) && IsIntegerLit(expr2)) {
            switch (tkn) {
            case T_SHL:
                expr->u.integerLit.value = expr->u.integerLit.value << expr2->u.integerLit.value;
                break;
            case T_SHR:
                expr->u.integerLit.value = expr->u.integerLit.value >> expr2->u.integerLit.value;
                break;
            default:
                /* not reached */
                break;
            }
        }
        else {
            int op;
            switch (tkn) {
            case T_SHL:
                op = OP_SHL;
                break;
            case T_SHR:
                op = OP_SHR;
                break;
            default:
                /* not reached */
                op = 0;
                break;
            }
            expr = MakeBinaryOpNode(c, op, expr, expr2);
        }
    }
Ejemplo n.º 5
0
/* ParseVariableDecl - parse a variable declaration */
static int ParseVariableDecl(ParseContext *c, char *name, VMVALUE *pSize)
{
    Token tkn;

    /* parse the variable name */
    FRequire(c, T_IDENTIFIER);
    strcpy(name, c->token);

    /* handle arrays */
    if ((tkn = GetToken(c)) == '[') {
        int size;

        /* check for an array with unspecified size */
        if ((tkn = GetToken(c)) == ']')
            size = 0;

        /* otherwise, parse the array size */
        else {
            ParseTreeNode *expr;

            /* put back the token */
            SaveToken(c, tkn);

            /* get the array size */
            expr = ParseExpr(c);

            /* make sure it's a constant */
            if (!IsIntegerLit(expr) || expr->u.integerLit.value <= 0)
                ParseError(c, "expecting a positive constant expression");
            size = expr->u.integerLit.value;

            /* only one dimension allowed for now */
            FRequire(c, ']');
        }

        /* return an array and its size */
        *pSize = size;
        return VMTRUE;
    }

    /* not an array */
    else
        SaveToken(c, tkn);

    /* return a scalar */
    return VMFALSE;
}
Ejemplo n.º 6
0
/* ParseConstantDef - parse a 'DEF <name> =' statement */
static void ParseConstantDef(ParseContext *c, char *name)
{
    ParseTreeNode *expr;
    Symbol *sym;

    /* get the constant value */
    expr = ParseExpr(c);

    /* make sure it's a constant */
    if (!IsIntegerLit(expr))
        ParseError(c, "expecting a constant expression");

    /* add the symbol as a global */
    sym = AddGlobal(c, name, SC_CONSTANT, expr->u.integerLit.value, 0);

    FRequire(c, T_EOL);
}