i	Instruction
S	Subroutine ID
E	Entry mark
R	Return mark

Construct(i):
	!F{}
;	!C{}
Entr:
	if S(i)
		if !E(i)
			End
		fi
		> PopC
	fi
	SpinLock(i)
	E(i)
	Sid = SID
	SID ++
Walk:
	S(i) = Sid
	Class = InsClass(i)
	if Class eq LIN
Line:
		k = i + InsSize(i)
		if S(k)
			if (S(k) <> Sid)
				End	; Merge
			fi
			> Pop
		fi
		i = k
		> Walk
		
	if Class eq JCC
		j = InsFlow(i)
		if S(j)
			if (S(j) <> Sid)
				if !E(j)	; Opt*
					End
				fi
			fi
		else
			Push(F{}, j)
		fi
		> Line
		
	if Class eq JPR
		j = InsFlow(i)
		if S(j)
			if (S(j) <> Sid)
				if !E(j)	; Opt*
					End
				fi
			fi
			> Pop
		fi
		i = j
		> Walk
		
	if Class eq JPI
; Construct/check at translation.
		> Pop
		
	if Class eq CLI
; Construct/check at translation.
		R(i + InsSize(i))
		> Line

	if Class eq CLR
; Construct/check at translation.
;		j = InsFlow(i)
;		if S(j)
;			if !E(j)
;				End
;			fi
;		else
;			Push(C{}, J)
;		fi
		R(i + InsSize(i))
		> Line
		
	if Class eq RET
Pop:
		i = Pop(F{})
		if i
			> Walk
		fi
		SpinUnlc(i)
PopC:
;		i = Pop(C{})
;		if i
;			> Entr
;		fi
		end
	fi

 ----

Sequence(i):
	SpinLock(i)
	Class = InsClass(i)
	if Class eq LIN
Line:
		k = i + InsSize(i)
		if S(k)
			if (S(k) <> S(i))
				End	; Merge
			fi
		fi

	if Class eq JCC
		j = InsFlow(i)
		if S(j)
			if (S(j) <> S(i))
				if !E(j)	; Opt*
					End
				fi
			fi
		fi
		> Lin

	if Class eq JPR
		j = InsFlow(i)
		if S(j)
			if (S(j) <> S(i))
				if !E(j)	; Opt*
					End
				fi
			fi
		fi
			
	if Class eq CLR
		j = InsFlow(i)
		if S(j)
			if !E(j)
				End
			fi
		else
			Construct(j)
		fi
		> Lin
		
	if Class eq RET
		j = Stack{}
		if S(j)
			if !R(j)
				if !E(j)	; Opt*
					End
				fi
				End
			fi
		else
			Construct(j)
		fi
	fi
	
	if Class eq JPI
		j = InsFlow(i)
		if S(j)
			if !E(j)	; Opt*
				End
			fi
		fi
		Construct(j)
	fi

	if Class eq CLI
		j = InsFlow(i)
		if S(j)
			if !E(j)	; Opt*
				End
			fi
		fi
		Construct(j)
		> Line
	fi