自学教程：C++ Expression函数代码示例

Expression Operator::operator*( const Expression    & arg ) const{ return Expression(*this)*arg; }

ConstraintComponent NonsmoothOperator::operator==( const VariablesGrid&  b ) const{ return Expression(*this) ==  b; }

//.........这里部分代码省略.........    else if( i==DOTCMD_RET )    {        /*        // .ret command        //        // Generate the line "jmp r30.w0"        // This makes us compatible with "CALL", although inexplicably,        // the CALL command is not a "dot" command.        //        */        if( TermCnt != 1 )            { Report(ps,REP_ERROR,"Expected no operands"); return(-1); }        if( Options & OPTION_RETREGSET )            { Report(ps,REP_ERROR,".ret incompatible with .setcallreg, use ret"); return(-1); }        if( Core > CORE_V1 )            { Report(ps,REP_ERROR,".ret illegal with specified core version, use ret"); return(-1); }        strcpy( Src, "jmp     r30.w0" );        return(strlen(Src));    }    else if( i==DOTCMD_ORIGIN )    {        int val,tmp;        char tstr[TOKEN_MAX_LEN];        /*        // .origin command        //        // Alter the origin for writing code        */        if( TermCnt != 2 )            { Report(ps,REP_ERROR,"Expected 1 operand"); return(-1); }        strcpy( tstr, pTerms[1] );        if( Expression(ps, tstr, (uint *)&val, &tmp)<0 )            { Report(ps,REP_ERROR,"Error in processing .origin value"); return(-1); }        if( Core == CORE_V0 )            { Report(ps,REP_ERROR,".origin illegal with specified core version"); return(-1); }        if( val<CodeOffset )            { Report(ps,REP_ERROR,".origin value is less than current offset"); return(-1); }        if( CodeOffset>=0 )            Report(ps,REP_WARN1,"Resetting .origin value after use");        if( EntryPoint<0 )            EntryPoint = val;        CodeOffset = val;        return(0);    }    else if( i==DOTCMD_ENTRYPOINT )    {        int val,tmp;        char tstr[TOKEN_MAX_LEN];        /*        // .entrypoint command        //        // Alter the origin for writing code        */        if( TermCnt != 2 )            { Report(ps,REP_ERROR,"Expected 1 operand"); return(-1); }        strcpy( tstr, pTerms[1] );        if( Expression(ps, tstr, (uint *)&val, &tmp)<0 )            { Report(ps,REP_ERROR,"Error in processing .entrypoint value"); return(-1); }        if( Core == CORE_V0 )            { Report(ps,REP_ERROR,".entrypoint illegal with specified core version"); return(-1); }

Expression NonsmoothOperator::operator-( ) const{ return -Expression(*this); }

LongIntEngineBase::get_next_value(const String &seq_name){    return select1(Expression(get_dialect()->select_next_value(seq_name)),            Expression(get_dialect()->dual_name()), Expression()).as_longint();}

void GetEA (EffAddr* A)/* Parse an effective address, return the result in A */{    unsigned long Restrictions;    token_t IndirectEnter;    token_t IndirectLeave;    const char* IndirectExpect;    /* Choose syntax for indirection */    if (BracketAsIndirect) {        IndirectEnter = TOK_LBRACK;        IndirectLeave = TOK_RBRACK;        IndirectExpect = "']' expected";    } else {        IndirectEnter = TOK_LPAREN;        IndirectLeave = TOK_RPAREN;        IndirectExpect = "')' expected";    }    /* Clear the output struct */    A->AddrModeSet = 0;    A->Expr = 0;    /* Handle an addressing size override */    switch (CurTok.Tok) {        case TOK_OVERRIDE_ZP:            Restrictions = AM65_DIR | AM65_DIR_X | AM65_DIR_Y;            NextTok ();            break;        case TOK_OVERRIDE_ABS:            Restrictions = AM65_ABS | AM65_ABS_X | AM65_ABS_Y;            NextTok ();            break;        case TOK_OVERRIDE_FAR:            Restrictions = AM65_ABS_LONG | AM65_ABS_LONG_X;            NextTok ();            break;        default:            Restrictions = ~0UL;        /* None */            break;    }    /* Parse the effective address */    if (TokIsSep (CurTok.Tok)) {        A->AddrModeSet = AM65_IMPLICIT;    } else if (CurTok.Tok == TOK_HASH) {        /* #val */        NextTok ();        A->Expr  = Expression ();        A->AddrModeSet = AM65_ALL_IMM;    } else if (CurTok.Tok == TOK_A) {        NextTok ();        A->AddrModeSet = AM65_ACCU;    } else if (CurTok.Tok == IndirectEnter) {        /* One of the indirect modes */        NextTok ();        A->Expr = Expression ();        if (CurTok.Tok == TOK_COMMA) {            /* (expr,X) or (rel,S),y */            NextTok ();            if (CurTok.Tok == TOK_X) {                /* (adr,x) */                NextTok ();                A->AddrModeSet = AM65_ABS_X_IND | AM65_DIR_X_IND;                Consume (IndirectLeave, IndirectExpect);            } else if (CurTok.Tok == TOK_S) {                /* (rel,s),y */                NextTok ();                A->AddrModeSet = AM65_STACK_REL_IND_Y;                Consume (IndirectLeave, IndirectExpect);                ConsumeComma ();                Consume (TOK_Y, "`Y' expected");            } else {                Error ("Syntax error");            }        } else {            /* (adr), (adr),y or (adr),z */            Consume (IndirectLeave, IndirectExpect);            if (CurTok.Tok == TOK_COMMA) {                /* (adr),y */                NextTok ();                switch (CurTok.Tok) {                case TOK_Z:                    /* only set by scanner.c if in 4510-mode */                    NextTok ();                    A->AddrModeSet = AM65_DIR_IND;//.........这里部分代码省略.........

Expression Operator::operator-( ) const{ return -Expression(*this); }