A2osX/BIN/ASM.S.EXP.txt

PR#3
PREFIX /A2OSX.SRC
NEW
INC 1
AUTO 6
					.LIST OFF
*---------------------------------------
* U-Operators :
* B-Operators :
* Num Format : 0-9 -> decimal
* 				$ = Hex
*				% = binary
*               & = octal
*               * = PC
*---------------------------------------
EXP.Eval			stz EXP.Operator

					jsr SRC.GetCharNB
					bne .13
					
					lda #ERR.MISSING.EXP
					sec
.14					rts

.13					cmp #'.'			Local Label?
					bne .12
					
					jsr EXP.GetLocal
					bcs .14			
					
					jmp EXP.EvalOperator
					
				
.12					cmp #'*'
					bne .10
					
					ldy #ASM.PC+3
					ldx #3
					
.11					lda (pData),y
					sta SRC.ACC,x
					dey
					dex
					bpl .11
					
					jsr SRC.GetCharNB
					bne EXP.EvalExitSYN
					clc
					rts
					
.10					jsr SRC.IsDigit10		Decimal constant ?
					bcs .1
					
					dec SRC.BufPtr
					jsr SRC.GetDecimal
					
					bcs EXP.EvalExitSYN
					bra EXP.EvalOperator
					
.1					cmp #'$'			Hex?
					bne .2
					jsr SRC.GetHex
					
					bcs EXP.EvalExitSYN
					bra EXP.EvalOperator
					
					
.2					cmp #'%'			binary?
					bne .3
					jsr SRC.GetBinary
					
					bcs EXP.EvalExitSYN
					bra EXP.EvalOperator
					
					
.3					cmp #'&'			octal?
					bne .4
					jsr SRC.GetOctal
					
					bcs EXP.EvalExitSYN
					bra EXP.EvalOperator					
					
.4					cmp #'''
					bne .43
					jsr SRC.GetChar
					beq EXP.EvalExitSYN
					jsr EXP.SetAccA
					jsr SRC.GetChar
					beq EXP.EvalOperator
					cmp #'''
					bne EXP.EvalExitSYN
					bra EXP.EvalOperator	
					
.43					cmp '"'
					bne .42
					jsr SRC.GetChar
					beq EXP.EvalExitSYN
					ora #$80
					jsr EXP.SetAccA
					jsr SRC.GetChar
					beq EXP.EvalOperator
					cmp #'"'
					bne EXP.EvalExitSYN
					bra EXP.EvalOperator	
					
.42					jsr SRC.IsLetter		Symbol ?
					bcs EXP.EvalExitSYN
					dec SRC.BufPtr
					jsr EXP.GetSymbol
					bcs EXP.EvalExitRTS
					bra EXP.EvalOperator
					
					
					
EXP.EvalExitOK		dec SRC.BufPtr		Back One Char				
EXP.EvalExitOK1		clc
EXP.EvalExitRTS		rts
					
EXP.EvalExitSYN		lda #ERR.SYNTAX.ERROR
					sec
					rts

EXP.EvalExitUND		lda #ERR.UNDEF.SYMBOL
					sec
					rts					
					
					
EXP.EvalOperator	lda EXP.Operator
					beq .7
					
					jsr EXP.Compute
					bcs EXP.EvalExitRTS
					
.7					jsr SRC.GetChar
					beq EXP.EvalExitOK1
					cmp #' '
					beq EXP.EvalExitOK1
					jsr SRC.IsAMReserved
					bcc EXP.EvalExitOK
					
					jsr SRC.IsEXPReserved
					bcs *
					bcs EXP.EvalExitSYN
					
					sta EXP.Operator
					
					ldx #3
.8					lda SRC.ACC,x
					sta SRC.ARG,x
					dex
					bpl .8
					
					jmp EXP.Eval
					
					clc
					rts
*---------------------------------------
EXP.GetLocal		jsr SRC.GetDecimal
					bcs EXP.EvalExitSYN
					lda SRC.ACC+1
					ora SRC.ACC+2
					ora SRC.ACC+3
					bne EXP.EvalExitSYN	Max .255
					lda SRC.ACC
					beq EXP.EvalExitSYN	.0 is not allowed
					jsr SYM.FindLocal
					bcs EXP.EvalExitUND
					rts
*---------------------------------------
EXP.SetAccA			sta SRC.ACC
					stz SRC.ACC+1
					stz SRC.ACC+2
					stz SRC.ACC+3
					rts
*---------------------------------------					
EXP.GetSymbol		>LDYA L.SRC.ELabel.Len
					jsr SRC.GetLabel
					bcs EXP.EvalExitSYN
					jsr SYM.FindGlobal
					bcc .1
	
					ldy #ASM.PASS		
					lda (pData),y		pass#2?
					bne EXP.EvalExitUND				yes, undefined symbol
					
					lda #$C0			Valid+Pending
					sta SRC.ELabel.Flags
					>LDYA L.SRC.ELabel.Flags
					jsr SYM.AddGToGBlockYA
					rts

.1					ldx #3
.2					lda SRC.FLabel.Value,x
					sta SRC.ACC,x
					dex
					bpl .2
					clc
					rts
*---------------------------------------
EXP.Compute			
					clc
					rts
*---------------------------------------
MAN
SAVE BIN/ASM.S.EXP
LOAD BIN/ASM.S
ASM