ssint.inc

Dos6.0

;*** 
;ssint.inc
;
;	Copyright <C> 1988 Microsoft Corporation
;
;
;*******************************************************************************

;SSINT	- Scanner internal interface definitions
SSINT_INC = ON

	IncludeOnce	architec
	IncludeOnce	scanner

;=============================================================
;Constants
;

LOWUND		EQU LOW UNDEFINED

RB_fSizeOp	EQU 80h 	;Rule table constant - indicates cbTyp operand

LineUpdate	=	64	;Number of lines scanned per screen update
				;MUST be power of two!!!

ET_FormRec	equ	ET_MAX

;=============================================================
;Scanner Stack Entry Definitions
;

;Scan stack frame ids - major types
STYP_If 	EQU 100h	;IF stack entry label
STYP_Else	EQU 200h	;opStElse that matches an If
STYP_For	EQU 400h	;FOR block identifier
STYP_DefFn	EQU 800h	;DEF FN block identifier
STYP_Do 	EQU 1000h	;DO block identifier
STYP_While	EQU 2000h	;WHILE block identifier
STYP_Case	EQU 4000h	;SELECT CASE block identifier
STYP_StackEnd	EQU 0		;End of stack token

;Scan stack frame ids - modifiers
STYP_Block	EQU  1		;TRUE for block varients of IF and ELSE
STYP_Lab	EQU  2		;Label varient of IF

STYP_Step	EQU  4h 	;STEP clause in FOR

STYP_DoWhile	EQU 10h 	;DO While varient of DO
STYP_DoUntil	EQU 20h 	;DO Until varient of DO
STYP_CaseTo	EQU 40h 	;CASE IS <const> TO <const> varient of SELECT
STYP_CaseRel	EQU 80h 	;CASE [IS <relop>] <const> varient of SELECT

;Scan stack frame ids - common combinations
STYP_IfLab	EQU  STYP_If OR STYP_Lab
				;Label varient of IF
				; Frame contains the oTx of the IF oTx field
STYP_IfBlock	EQU  STYP_If OR STYP_Block
				;Block IF stack entry label
				; Frame contains the oTx of the IF oTx field
STYP_ElseBlock	EQU  STYP_Else OR STYP_Block
				;opStElse that matches an IfBlock
STYP_ElseNop	EQU  STYP_Else OR STYP_Lab
				;opStElseNop which matches a preceding opStIfLab

;The following stack frame identifiers are used on the debug stack only.
STYP_Exp	EQU -5		;Present in debug stack only.
STYP_VtRf	EQU -4		;Present in debug stack only.
STYP_AVtRf	EQU -3		;Present in debug stack only.
STYP_ArgCnt	EQU -2		;Present in debug stack only.

;===========================================================================
;Scan stack Structure Definitions
;
;The following structures are present on the scan stack.

;FOR structure is used for all varients of FOR (but not EXIT FOR).
FFOR	STRUC
FFOR_Id 	DW 0
FFOR_oTx	DW 0
FFOR_oTxExit	DW 0 ;Must align with FDO_oTxExit
FFOR_oTxIdRf	DW 0
FFOR_oTyp	DW 0
FFOR	ENDS

;IF structure is used for all varients of IF/THEN/ELSEIF

FIF	STRUC
FIF_Id		DW 0
FIF_oTx 	DW 0
FIF_oTxBranch	DW 0
FIF	ENDS

;DO structure is used for all looping constructs DO/LOOP, and WHILE/WEND

FDO	STRUC
FDO_Id		DW 0
FDO_oTxLoop	DW 0
FDO_oTxExit	DW 0 ;Must align with FFOR_oTxExit
FDO	ENDS

;SELECT CASE structure is used for all varients of SELECT CASE / END SELECT

FCASE	STRUC
FCASE_Id	DW 0
FCASE_oTyp	DW 0
FCASE_oTxBranch DW 0
FCASE_oTxTrue	DW 0
FCASE_oTxFalse	DW 0
FCASE	ENDS

;Expressions

FEXP	STRUC
FEXP_oTyp	DW 0
FEXP_oTx	DW 0
FEXP	ENDS

;===========================================================================
;oType contains two fields.
;	The low 13 bits is either a key value for native types or is an
;	offset into the type table to a user defined type definition.
;	The high 3 bits are used by the scanner to identify the origin
;	of the argument to handle several special cases. (ST=scanner type)

ET_RC	equ	0		;Scan stack only ET type for records

;Flag bits in high byte of scan stack oTyp entry
ST_Form	=	1
ST_Seg	=	8
ST_ByVal=	10H

ST_Typ_Mask =	00ffh		;oTyp stored in low byte. Records use ET_RC.

ST_Flags=	not ST_Typ_Mask ;Mask for flag field
ST_Bits =	2000h		;First available bit

;		0*ST_Bits	;All expressions not covered by below
ST_Marker=	1*ST_Bits	;Marker for non-oType stack entries
ST_Lit	=	2*ST_Bits	;Argument is literal without operand
				;  (Replace executor to coerce to R4)
ST_LitX =	3*ST_Bits	;Argument is literal with operand or with unary minus
				;  (OK for static array in DIM index)

;For these types, Ld executors get replaced with Rf's on procedure calls
ST_ArrVar=	4*ST_Bits	;Argument is from opAIdLd
ST_SimpVar=	5*ST_Bits	;Argument is from opIdLd
ST_RecArVar=	6*ST_Bits	;Argument is from opOffLd off array
ST_RecScVar=	7*ST_Bits	;Argument is from opOffLd off scalar

;Derived bit patterns to optimize certain tests
;WARNING!! Some scanner code is very sensitive to bit assignments!
ST_Lit? =	ST_Lit and ST_LitX		;non-zero if literal
ST_RecVar=	ST_RecArVar and ST_RecScVar
ST_Var? =	ST_SimpVar and ST_ArrVar and ST_RecVar
ST_Array?=	ST_Flags and not ST_ArrVar	;Test zero if array var.
ST_Record?=	ST_RecVar and not ST_Var?	;Test non-zero if record
ST_ArrayBit=	ST_ArrVar xor ST_SimpVar	;Bit set if not array

;======================================================================
;SsRefarg flags
;Passed in dh to indicate details of required reference argument
;These must be the same as certain bit assignments in SsProc.
;Verification is made there.
Lvalue	=	3			;Indicates copy back needed
FarArg	=	28H			;Make sure argument is FAR
FScb	=	10H			;Far ref w/length to be used for FS

;======================================================================
;SsBosFlags definitions
;	These flags show state that lasts during a statement.
;	SsBosFlags is set to zero at each BOS.
;
SSBOSF_StCommon EQU	1	;COMMON statement detected
SSBOSF_StShared EQU	2	;SHARED statement detected
SSBOSF_StStatic EQU	4	;STATIC statement detected
SSBOSF_Const	EQU	8	;Scanning CONST statement
SSBOSF_Inserted EQU	10H	;Insertion occured in this statement
SSBOSF_PcUpdate EQU	20H	;PC update pcode exists in this statement
SSBOSF_StCase	EQU	40H	;CASE syntax processing required for this line

;General-purpose scanner flags, kept in SsFlags:
SSF_ScanAndExec EQU	1	;ScanAndExec is processing CONST statement
SSF_HaveDimmed	EQU	2	;Have done a DIM: OPTION BASE illegal
SSF_If		EQU	4	;IF syntax processing required for this line
SSF_StSelect	EQU	8	;SELECT CASE <stmt lst> CASE checking is
				;required
SSF_InType	EQU	10H	;Inside a TYPE declaration
SSF_CantCont	EQU	20H	;Call CantCont at end of scan

;=======================================================================
;Text table link list maintenance structure.  This structure is allocated
;as a local variable on the scanner stack.
;

TXLNK		STRUC
TXLNK_LabDefNext	DW 0	;oTx of next link in label definition list
TXLNK_LabDefLast	DW 0	;oTx of last link in label definition list
TXLNK_Data		DW 0	;oTx of last link in DATA list
TXLNK_DefType		DW 0	;oTx of last link in DEFtyp list
TXLNK_Type		DW 0	;oTx of last link in TYPE/END TYPE list
TXLNK_DefFn		DW 0	;oTx of last link in DEF FN/END DEF list
TXLNK		ENDS

;SSL		STRUC
;SSL_oTxLabDefNext	DW 0	;offset of next label definition
				;(unrelocated for expansion.)
;SSL_oTxLabDefLast	DW 0	;offset of last bound label definition
;SSL		ENDS

;=======================================================================
;Data segment locations
;


sBegin	DATA
ife	SSDATA_ASM
extrn	SsErrOTx:word		;oTx of pcode which was replaced by opEot
extrn	SsErr:word		;Error code to be returned by scanner.
extrn	SsErrOpcode:word	;Opcode which was replaced by opEot
extrn	SsDelayErr:word		;Error code of delayed error
extrn	SsDelayLoc:word		;oTx of delayed error
extrn	SsDelayCnt:word		;Count of pending delayed errors
extrn	SsStackSave:word	;Scanner sp at start of scan loop

extrn	f_Static:byte		;TRUE if current array type default is $STATIC

extrn	f_StaticCalc:byte	;TRUE if current array would be $STATIC if this
				; were the first reference.

extrn	SsExec:word		;SsExecFlag and SsExecTmp together
extrn	SsExecFlag:byte		;OPA_fExecute ORed in if can't allow COMMON
extrn	SsExecTmp:byte		;Temporary hold for SsExecFlag during CONST
extrn	ScanRet:word		;Contains address of scanner main loop
extrn	SsOTxBOS:word		;Offset of last encountered BOS
extrn	SsOTxPatchBos:word	;Address of executor to be patch with Bos
extrn	SsOTxStart:word 	;Address of point were stack was clear.  This
				;is used to find the bounds for Dim as well as
				;the insertion point for CDecl calls.
extrn	ScannerFlags:word	;SsBosFlags and SsFlags together
extrn	SsBosFlags:byte		;Scanner begin of statement flags
extrn	SsFlags:byte		;General scanner flags
extrn	SsCbTxExpand:word	;CB of text expansion during scanning.
extrn	SsLinkCtl:word		;Label Control Structure
extrn	SsCbFrameTemp:word	;Temp space for current statement

;Data for update of return addresses on stack
extrn	SsNextOTx:word		;oTx of return address
extrn	SsReturnBp:word		;offset in stack of return frame

;ScanAndExec data
extrn	SsScanExStart:word	;Starting address of execution
extrn	SsScanExSrc:word	;oTx of original source

	;Data used by ssproc to count param bytes for CDECL calls

extrn	SsCbParmCur:word	;cb of all params so far
extrn	SsParmCnt:word		;Number of parameters

extrn	SsOtxHeapMove:word	;oTx of last possible heap movement
extrn	SsBosStack:word		;SP-2 at start of statement

endif			;SSDATA_ASM
sEnd	DATA


;=======================================================================
;Entrypoints defined in SsScan.asm
;

ife	SSSCAN_ASM
	extrn	ScanExExit:far	;jmp here to terminate execution from scanner
endif				;ife SSSCAN_ASM

sBegin	SCAN			

ife	SSSCAN_ASM
extrn	ScanExit:near		;jmp here when scan is complete
extrn	SsScanExExit:near	;jmp here when scan of ScanAndExec is done
extrn	ExecuteFromScan:near	;Fire up execution from scanner

extrn	SsError:near		;Scanner error handler
extrn	SsErrorBx:near		;Scanner error handler--emit oTx bx