> NotEquateDefinition: mov bx,#InvalidInstrMessage call PanicRecover DefineNewSymbol: call FindSymbol jc NotaRedefinition mov ax,PresentFileNameOffset mov DefFileNameOffset[di],ax mov ax,InputLineNumber mov DefLineNumber[di],ax test Attributes[di],#IsDefined jz DefiningNow mov bx, #RedefinitionMessage call PanicRecover NotaRedefinition: call AddSymbol DefiningNow: push di call IgnoreSpaces call GetChar cmpb al,#':' jnz NotLabelDefinition mov ax,LocationCounter mov bx,#Calculated jmps ValidSymbolDefinition NotLabelDefinition: cmpb al,#'=' jnz NotEquateDefinition call GetToken call ProcessExpression ValidSymbolDefinition: pop di or bx,#IsDefined mov Attributes[di],bx mov Value[di],ax ret ProcessExpression: |maintain flags upto compile mov di,#PostFixBufferStart push LastFilledSymbol push StringSpace call CompileExpression mov si,#PostFixBufferStart call EvaluateExpression mov bx,#9 |IsEquate or Calculated jc NotEvaluatable |reclaim strings and entries pop StringSpace |Evaluatable pop LastFilledSymbol mov di,LastFilledSymbol mov [di],#0 ret NotEvaluatable: pop cx |The old StringSpace can go to the moon, new fake symbols added pop cx |and the filledsymbol and bx, #NotCalculated call IsSimpleExpression jnz NotSimpleExpression or bx, #IsFake |not calculated and fake | call DisplayRegister | call DisplayMessage | db ':Found S ',0 | push ax | mov ax,LastFilledSymbol | call DisplayRegister | pop ax | call DisplayMessage | db 0dh,0ah,0 ret NotSimpleExpression: |Has to be stored on the string space mov ax, StringSpace push ax call TransferExprToSpace pop ax mov StringSpace,di ret DecimalConvertNumber: mov si,#InputWord cmpb [si],#''' jz CharLiteralFound cmpb 1[si],#'x' |Hex Number jz HexNumberFound xor ax,ax mov bx,#10 xor dx,dx DecConvNumber1: mov cx,ax xorb ah,ah lodsb call IsNumAL jnc FinishedDecimalConvert sub ax,#48 xchg cx,ax mul bx or dx,dx jnz ReportLargeDecConst add ax,cx jc ReportLargeDecConst jmps DecConvNumber1 FinishedDecimalConvert: mov ax,cx ret HexNumberFound: inc si |get past the 0x inc si xor ax,ax HexNumberFound1: mov cx,ax lodsb call IsHexAL jnc FinishedDecimalConvert subb al,#'0' cmpb al,#10 jc ZeroToNine subb al,#7 ZeroToNine: shl cx jc ReportLargeDecConst shl cx jc ReportLargeDecConst shl cx jc ReportLargeDecConst shl cx jc ReportLargeDecConst xorb ah,ah or ax,cx jmps HexNumberFound1 ReportLargeDecConst: mov bx, #LargeConstMessage call PanicRecover CharLiteralFound: movb al,1[si] movb ah,#0 ret TransferExprToSpace: mov di, StringSpace mov si, #PostFixBufferStart ExprTransferNext: lodsw stosw call CheckStringTableOverflow or ax,ax jz ExprTransferEnd movb cl,ah orb cl,cl jz ExprTransferNext ExprTransferSame: lodsw stosw decb cl jnz ExprTransferSame jmps ExprTransferNext ExprTransferEnd: ret IsSimpleExpression: push si mov si,#PostFixBufferStart lodsw cmp ax,#256 |0100 for single operand jnz SimpleExprEnd lodsw lodsw cmp ax,#0 jnz SimpleExprEnd mov ax,-4[si] SimpleExprEnd: pop si ret |This routine gets an operand from the input | GotRegister: movb al,[si] ret OperandExpected: mov bx,#OperandExpectedMessage call PanicRecover GetBasicOperand: push bx call GetToken pop bx jc OperandExpected mov si,#InputWord lodsb call IsAlphaAL jnc NotARegister |A Register always start with a character cmpb 1[si],#0 |A Register name is always 2 chars jnz NotARegister mov si,#SmallRegisters push bx call MatchKeyword pop bx movb cl,#1 jnc GotRegister mov si,#BigRegisters push bx call MatchKeyword pop bx movb cl,#2 jnc GotRegister mov si,#SegmentRegisters push bx call MatchKeyword pop bx movb cl,#3 jnc GotRegister NotARegister: cmpb al,#'#' jnz NotanImmediate call GetExprValInd movb cl,#4 ret NotanImmediate: cmpb InputWord,#'[' jnz NotAnAddressingMode call GetAddressingMode movb cl,#5 ret NotAnAddressingMode: | call DisplayMessage | db 'calling',0dh,0ah,0 call GetExprValInd1 pushf | call DisplayRegister cmpb InputWord,#'[' jz HasAddressToo popf movb cl,#6 ret HasAddressToo: push ax call GetAddressingMode pop ax popf movb cl,#7 ret CompilerFakes: .word 0 GetExprValInd1: push bx clc jmps GEVI1 GetExprValInd: push bx call GetToken GEVI1: call ProcessExpression test bx,#Calculated jnz ExprValueFound test bx,#IsFake jnz GotExprIndex push ax push bx call BackupInputWord mov di,#InputWord movb al,#'_' stosb stosb inc CompilerFakes mov ax,CompilerFakes call SprintRegister xorb al,al stosb call AddSymbol call RestoreInputWord pop bx pop ax or bx,#IsDefined | or bx,#IsFake mov Value[di],ax mov Attributes[di],bx mov ax,di GotExprIndex: pop bx call AddOffEnt stc ret ExprValueFound: pop bx clc ret WrongMode: mov bx,#InvalidAddrMode call PanicRecover GetAddressingMode: call GetToken mov si,#AddressingModes call MatchKeyword jc WrongMode call GetToken cmpb InputWord,#']' jnz WrongMode movb bl,[si] ret GetOperand: push si call GetBasicOperand pop si pushf cmpb cl,#3 jnc NotNormalRegister orb al,#192 NoValues: xorb ah,ah GetOperandEnd: popf ret NotNormalRegister: cmpb cl,#3 jnz NotSegmentRegister shlb al shlb al shlb al jmp NoValues NotSegmentRegister: cmpb cl,#4 jnz NotanImmediate1 mov bx,ax xorb ch,ch popf pushf adcb ch,#0 movb ah,#2 jmp GetOperandEnd NotanImmediate1: cmpb cl,#5 jnz NotJustMode movb al,bl jmp NoValues NotJustMode: xchg bx,ax cmpb cl,#6 jnz NotJustDisp xorb ch,ch popf pushf jnc KnownMode incb ch mov bx,#1 KnownMode: movb al,#6 movb ah,#2 jmp GetOperandEnd NotJustDisp: movb ch,#0 popf pushf jc DispUnknown orb bh,bh jnz DispEnd movb ah,#1 orb al,#64 jmp GetOperandEnd DispUnknown: movb ch,#1 mov bx,#1 DispEnd: movb ah,#2 orb al,#128 jmp GetOperandEnd