sys7.1-doc-wip/Internal/Asm/InternalMacros.a

;
;	File:		InternalMacros.a
;
;	Contains:	generally useful macros
;
;	Written by:	Darin Adler
;
;	Copyright:	© 1989-1990, 1992 by Apple Computer, Inc., all rights reserved.
;
;	Change History (most recent first):
;
;		 <2>	 3/24/92	PN		<kc> Fix bug in endPreviousWith (changed WithModule to
;									endWithModule).
;		 <6>	 1/30/91	gbm		sab, #38: Change the ‘already including this file’ variable to
;									all uppercase (for security reasons)
;		 <5>	 9/25/90	KIP		(really dba) DT.W now works on lists of items
;		 <4>	  6/8/90	dba		change so that debug switch defaults to 0
;		 <2>	 4/17/90	dba		change nil and false and true to defaults
;	   <1.1>	11/14/89	dba		fixed Symbol and added scott’s cool ideas from Finder to it
;	   <1.0>	  6/2/89	prp		Initial release. Folder Manager now part of Alias Manager.
;				  6/2/89	dba		rolled into system; fixed bug in linkFrame macro
;				  5/6/89	dba		new today
;
;	To Do:
;		optimize for non-68000 assemblies
;		keep a stack of saved register sets
;

	IF &TYPE('__INCLUDINGINTERNALMACROS__') = 'UNDEFINED' THEN
__INCLUDINGINTERNALMACROS__	SET	1

; do an equ if the symbol is not already defined

		macro
&symbol	default		&value

	if &type(&symbol) = 'UNDEFINED' then
		&symbol: equ &value
	endif

		endm

; a few symbols

	nil: default 0
	false: default 0
	true: default 1
	DEBUG: default false

; assert that a condition is true

		macro
		assert &condition

	if &eval(&condition) = false then
		aerror 'assert: failed'
	endif

		endm

; end a record and declare a size field

		macro
		endrsize

	org
	size: equ *
	endr

		endm

; push something onto the stack

		macro
		push.&size	&operand

	move.&size &operand,-(sp)

		endm

; pop something off of the stack

		macro
		pop.&size	&operand

	move.&size (sp)+,&operand

		endm

; reserve space on the stack

		macro
		rsrv.&size	&number
	lcla &bytes
	lclc &sizeLetter

	; calculate the default size is 1

	if &number = '' then
		&bytes: seta 1
	else
		&bytes: seta &eval(&number)
	endif

	; the size letter is required

	&sizeLetter: setc &upCase(&size)
	if &sizeLetter = 'L' then
		&bytes: seta 4 * &bytes
	elseif &sizeLetter = 'W' then
		&bytes: seta 2 * &bytes
	elseif &sizeLetter = 'B' then
		&bytes: seta (&bytes + 1) and (~1)	; round up to a word, since this is the stack
	else
		aerror &concat('rsrv: bad size letter: ',&size)
	endif

	; assembler optimization does the rest

	if &bytes < 0 then
		aerror &concat('rsrv: negative byte count: ', &bytes)
	elseif &bytes and 1 then
		aerror &concat('rsrv: odd byte count: ', &bytes)
	else
		sub.l #&bytes,sp
	endif

		endm

; free space from the stack

		macro
		free.&size	&number
	lcla &bytes
	lclc &sizeLetter

	; calculate the default size is 1

	if &number = '' then
		&bytes: seta 1
	else
		&bytes: seta &eval(&number)
	endif

	; the size letter is required

	&sizeLetter: setc &upCase(&size)
	if &sizeLetter = 'L' then
		&bytes: seta 4 * &bytes
	elseif &sizeLetter = 'W' then
		&bytes: seta 2 * &bytes
	elseif &sizeLetter = 'B' then
		&bytes: seta (&bytes + 1) and (~1)	; round up to a word, since this is the stack
	else
		aerror &concat('free: bad size letter: ',&size)
	endif

	; assembler optimization does the rest

	if &bytes < 0 then
		aerror &concat('free: negative byte count: ', &bytes)
	elseif &bytes and 1 then
		aerror &concat('free: odd byte count: ', &bytes)
	else
		add.l #&bytes,sp
	endif

		endm

; move condition codes

		macro
		moveccr		&destination

	move.w sr,&destination

		endm

; save some registers on the stack, possibly changing the condition codes

		macro
		save		&registers,&preserve==0
	gblc &savedRegisters
	gbla &port

	if &savedRegisters <> '' then
		aerror 'save: two without an intervening restore'
	endif

	&port: seta false
	if &registers = '' then
		&savedRegisters: setc 'none'
	elseif &upCase(&registers) = 'THEPORT' then
		&savedRegisters: setc 'none'
		&port: seta true
	else
		if &upCase(&subStr(&registers, &len(&registers) - 7, 8)) = '/THEPORT' then
			&savedRegisters: setc &subStr(&registers, 1, &len(&registers) - 8)
			&port: seta 1
		else
			&savedRegisters: setc &registers
		endif

		if &subStr(&type(&savedRegisters), 1, 5) = 'REG A' then
			move.l &savedRegisters,-(sp)
		elseif &subStr(&type(&savedRegisters), 1, 4) = 'REG ' then
			if &preserve then
				movem.l &savedRegisters,-(sp)
			else
				move.l &savedRegisters,-(sp)
			endif
		else
			movem.l &savedRegisters,-(sp)
		endif
	endif

	if &port then
		rsrv.l
		movem.l d0-d2/a0-a1,-(sp)

		if &preserve then
			moveccr -(sp)
			pea 2+5*4(sp)
		else
			pea 5*4(sp)
		endif

		_GetPort

		if &preserve then
			move.w (sp)+,ccr
		endif

		movem.l (sp)+,d0-d2/a0-a1
	endif

	if DEBUG then
		pea ('save')
	endif

		endm

; restore some registers saved by a save macro

		macro
		restore		&preserve==0
	gblc &savedRegisters
	gbla &port

	if &savedRegisters = '' then
		aerror 'restore: without save'
	else
		if DEBUG then
			if &preserve then
				moveccr -(sp)
				cmp.l #('save'),2(sp)
			else
				cmp.l #('save'),(sp)+
			endif

			beq.s @goodSave
			_Debugger
			@goodSave:

			if &preserve then
				move.w (sp)+,ccr
				free.l
			endif
		endif

;	*** handle case where register is already saved

		if &port then
			movem.l d0-d2/a0-a1,-(sp)

			if &preserve then
				moveccr -(sp)
				move.l 2+5*4(sp),-(sp)
			else
				move.l 5*4(sp),-(sp)
			endif

			_SetPort

			if &preserve then
				move.w (sp)+,ccr
			endif

			movem.l (sp)+,d0-d2/a0-a1
			free.l
		endif

		if &savedRegisters <> 'none' then
			if &subStr(&type(&savedRegisters), 1, 5) = 'REG A' then
				move.l (sp)+,&savedRegisters
			elseif &subStr(&type(&savedRegisters), 1, 4) = 'REG ' then
				if &preserve then
					movem.l (sp)+,&savedRegisters
				else
					move.l (sp)+,&savedRegisters
				endif
			else
				movem.l (sp)+,&savedRegisters
			endif
		endif
		&savedRegisters: setc ''
	endif

		endm

; pad a piece of memory to blockSize items (item is either bytes, words, or longs)

		macro
		pad.&size	&blockSize,&startLabel,&itemValue==0
	lcla &padItems
	lclc &sizeLetter

	&padItems: seta &eval(&blockSize) - (* - &eval(&startLabel))

	&sizeLetter setc &upCase(&sizeLetter)
	if &sizeLetter = '' then
		&sizeLetter: setc 'B'
	elseif &sizeLetter = 'B' then
	elseif &sizeLetter = 'W' then
		&padItems: seta &padItems div 2
	elseif &sizeLetter = 'L' then
		&padItems: seta &padItems div 4
	else
		aerror &concat('pad: cannot handle unknown item length: ',&size)
	endif

	if &padItems < 0 then
		aerror 'pad: cannot pad a block bigger than the block size'
	elseif &padItems > 0 then
		dcb.&itemtype &padItems,&itemValue
	endif

		endm

; create a jump table starting with the label and having a given prefix

		macro
&name	Table		&prefix,&base
	lclc &tableName
	gblc &tablePrefix,&tableBase

	if &name = '' then
		&tableName: setc '@table'
	else
		&tableName: setc &name
	endif

	&tablePrefix: setc &prefix

	if &base = '' then
		&tableBase: setc &tableName
	elseif &upCase(&base) = 'ABSOLUTE' then
		&tableBase: setc ''
	else
		&tableBase: setc &base
	endif

	&tableName:

		endm

; create a jump table entry

		macro
		dt.&size
	gblc &tablePrefix,&tableBase
	lcla &index

	&index: seta 0
	while &index < &nbr(&syslist) do
		&index: seta &index + 1
		if &tableBase = '' then
			dc.&size &concat(&tablePrefix, &syslist[&index])
		else
			dc.&size &concat(&tablePrefix, &syslist[&index], '-', &tableBase)
		endif
	endwhile

		endm

; end the with from a previous stack frame (never called directly)

		macro
		endPreviousWith
	gblc &frameState,&endWithModule

		if &sysMod = &endWithModule then
			endwith
		endif
		&frameState: setc ''

		endm

; declare some results in a stack frame

		macro
		resultsStackFrame	&frame
	gblc &frameName,&frameState,&endWithModule

	if &frameState = 'needEndWith' then
		endPreviousWith
	endif

	if &frameState = '' then
		if &frame = '' then
			&frameName: setc 'StackFrame'
		else
			&frameName: setc &frame
		endif
		&frameName: record {savedA6},decr
		&frameState: setc 'results'
	elseif &frameState = 'results'
		aerror 'resultsStackFrame: two without intervening endStackFrame'
	else
		aerror 'resultsStackFrame: must come before parameters and locals'
	endif

		endm

; declare some parameters in a stack frame

		macro
		parametersStackFrame	&frame
	gblc &frameName,&frameState,&endWithModule

	if &frameState = 'needEndWith' then
		endPreviousWith
	endif

	if &frameState = '' then
		resultsStackFrame	&frame
	endif

	if &frameState = 'results' then
		belowParameters: equ *
		&frameState: setc 'parameters'
	elseif &frameState = 'parameters' then
		aerror 'parametersStackFrame: two without intervening endStackFrame'
	else
		aerror 'parametersStackFrame: must come before locals'
	endif

		endm

; declare some locals in a stack frame

		macro
		localsStackFrame	&frame
	gblc &frameState

	if &frameState = 'needEndWith' then
		endPreviousWith
	endif

	if &frameState = '' then
		resultsStackFrame	&frame
	endif

	if &frameState = 'results' then
		parametersStackFrame
	endif

	if &frameState = 'parameters' then
		org
		parametersSize: equ belowParameters - *
		returnAddress: ds.l 1
		savedA6: ds.l 1
		&frameState: setc 'locals'
	else
		aerror 'localsStackFrame: two without intervening endStackFrame'
	endif

		endm

; end a stack frame

		macro
		endStackFrame
	gblc &frameName,&frameState

	if &frameState = 'results' then
		parametersStackFrame
	endif

	if &frameState = 'parameters' then
		localsStackFrame
	endif

	if &frameState = 'locals' then
		org
		align
		localsSize: equ *
		endr
		&frameState: setc 'needWith'
	else
		aerror 'endStackFrame: without results or parameters or locals'
	endif

		endm

; use instead of a link or for debugging

		macro
		linkFrame	&size
	gblc &linkState,&frameName,&frameState,&endWithModule

	if &linkState = '' then
		if &frameState = 'needWith' then
			with &frameName
			&frameState: setc 'needEndWith'
			&endWithModule: setc &sysMod
			link a6,#localsSize
			if &size ≠ '' then
				aerror 'linkFrame: specified frame and a specific size'
			endif
			&linkState: setc 'needUnlink'
		elseif &size = '' then
			if DEBUG then
				link a6,#0
				unlk a6
			endif
			&linkState: setc 'needFakeUnlink'
		else
			link a6,#&size
			&linkState: setc 'needUnlink'
		endif

		if DEBUG then
			pea ('link')
		endif
	else
		aerror 'linkFrame: missing unlinkFrame'
	endif

		endm

; use for any kind of unlink

		macro
		unlinkFrame	&preserve==0
	gblc &linkState

	if DEBUG then
		if &preserve then
			moveccr -(sp)
			cmp.l #('link'),2(sp)
		else
			cmp.l #('link'),(sp)+
		endif

		beq.s @goodUnlink
		_Debugger
		@goodUnlink:

		if &preserve then
			move.w (sp)+,ccr
			free.l
		endif
	endif

	if &linkState = 'needUnlink' then
		unlk a6
		&linkState: setc ''
	elseif &linkState = 'needFakeUnlink' then
		if DEBUG then
			bra.s @skipUnlink
			unlk a6
			@skipUnlink:
		endif
		&linkState: setc ''
	else
		aerror 'unlinkFrame: missing linkFrame'
	endif

		endm

; fake rts for debugging only

		macro
		noReturn
	gblc &linkState

	if &linkState ≠ '' then
		unlinkFrame
	endif

	if DEBUG then
		bra.s @skipReturn
		rts
		@skipReturn:
	endif

		endm

; rts

		macro
		return		&size
	gblc &linkState,&frameState
	lcla &bytes

	if &linkState ≠ '' then
		unlinkFrame
	endif

	if &size = '' then
		if &frameState = '' then
			&bytes: seta 0
		else
			&bytes: seta parametersSize
		endif
	elseif &subStr(&size, 1, 1) = '#' then
		&bytes: seta &strToInt(&subStr(&size, 2, &len(&size) - 1))
	else
		aerror 'return: bad size'
	endif

	if &bytes = 0 then
		rts
	elseif &bytes = 4 then
		move.l (sp)+,(sp)
		rts
	else
		move.l (sp)+,a0
		free.b &bytes
		jmp (a0)
	endif

		endm

; debugging symbol

		macro
		symbol		&routineName=&SysMod,&size=0
	lclc &name, &oldString

	if DEBUG then
		if &routineName[1:1] = '''' then
			&name: setc &eval(&routineName)
		else
			&name: setc &routineName
		endif

		&oldString: setc &setting('string')
		string asis
		if &len(&name) < 32 then
			dc.b &len(&name)+$80,'&name'
		else
			dc.b $80,&len(&name),'&name'
		endif
		string &oldString
		align
		dc.w &size
	endif

		endm

; composite macros for even shorter use

		macro
		linkSave	&registers

	linkFrame
	save &registers

		endm

		macro
		restoreUnlinkReturn

	restore
	unlinkFrame
	return
	symbol

		endm

	
		macro
		getCaseState

	gblc	&savedCaseState
	&savedCaseState:	SETC	&SETTING('CASE')
		
		endm
		
		macro
		restoreCaseState
		
	gblc	&savedCaseState
	CASE	&savedCaseState
		
		endm

asmNeedsDSWorkaround	default		true

	if asmNeedsDSWorkaround then

		macro
&label:	dsWorkaround &recordName

		lclc &savedCaseState
		lclc &upperCaseLabel

		&savedCaseState: setc &setting('CASE')
		if &savedCaseState = 'ON' then
			&label: ds.b &recordName
		else
			case on
			&upperCaseLabel: setc &upcase(&label)
			&upperCaseLabel: ds.b &recordName
			case &savedCaseState
		endif

		endm

		macro
&label:	equWorkaround &someName

		lclc &savedCaseState
		lclc &upperCaseLabel

		&savedCaseState: setc &setting('CASE')
		if &savedCaseState = 'ON' then
			&label: ds.b &someName
		else
			case on
			&upperCaseLabel: setc &upcase(&label)
			&upperCaseLabel: ds.b &someName
			case &savedCaseState
		endif

		endm
		
	else

		macro
&label:	dsWorkaround &recordName
		&label: ds.b &recordName
		endm

		macro
&label:	equWorkaround &someName
		&label: ds.b &someName
		endm

	endif

	ENDIF	; ...already included