93 lines
		
	
	
	
		
			2.6 KiB
		
	
	
	
		
			Text
		
	
	
	
	
	
			
		
		
	
	
			93 lines
		
	
	
	
		
			2.6 KiB
		
	
	
	
		
			Text
		
	
	
	
	
	
/*
 | 
						|
 * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
 | 
						|
 * See the copyright notice in the ACK home directory, in the file "Copyright".
 | 
						|
 */
 | 
						|
/* $Id$ */
 | 
						|
/*	Lint state stack	*/
 | 
						|
 | 
						|
/* These datastructures are used to implement a stack on which the
 | 
						|
 * state of automatic variables (including register variables) is
 | 
						|
 * kept.
 | 
						|
 * In this way it is possible to account for the flow of
 | 
						|
 * control of the program.
 | 
						|
 */
 | 
						|
 | 
						|
#define	TEST_VAR	0		/* not a constant */
 | 
						|
#define	TEST_TRUE	1		/* always true */
 | 
						|
#define	TEST_FALSE	2		/* always false */
 | 
						|
 | 
						|
struct loop_state {			/* used in lint_end_state only */
 | 
						|
	int lps_test;			/* is the test a constant? */
 | 
						|
	struct state *lps_body;
 | 
						|
	struct state *lps_loop;
 | 
						|
};
 | 
						|
 | 
						|
struct switch_state {			/* used in lint_end_state only */
 | 
						|
	struct state *sws_case;
 | 
						|
	struct state *sws_break;
 | 
						|
	int sws_default_met;
 | 
						|
};
 | 
						|
 | 
						|
/*	This union describes the (possibly incomplete) state at the end of the
 | 
						|
	mentioned construct.
 | 
						|
*/
 | 
						|
union lint_end_state {			/* used in lint_stack_entry only */
 | 
						|
	struct state *ule_if;
 | 
						|
	struct loop_state ule_loop;
 | 
						|
	struct switch_state ule_switch;
 | 
						|
};
 | 
						|
 | 
						|
struct lint_stack_entry {
 | 
						|
	struct lint_stack_entry *next;
 | 
						|
	struct lint_stack_entry *ls_previous;
 | 
						|
	int ls_level;
 | 
						|
	struct state *ls_current;	/* used by all classes */
 | 
						|
	short ls_class;			/* IF, WHILE, DO, FOR, SWITCH, CASE */
 | 
						|
	union lint_end_state ls_end;
 | 
						|
};
 | 
						|
 | 
						|
/* ALLOCDEF "lint_stack_entry" 10 */
 | 
						|
 | 
						|
/* macros to access the union */
 | 
						|
#define LS_IF	 	ls_end.ule_if
 | 
						|
#define LS_TEST		ls_end.ule_loop.lps_test
 | 
						|
#define LS_BODY		ls_end.ule_loop.lps_body
 | 
						|
#define LS_LOOP		ls_end.ule_loop.lps_loop
 | 
						|
#define LS_CASE		ls_end.ule_switch.sws_case
 | 
						|
#define LS_BREAK	ls_end.ule_switch.sws_break
 | 
						|
#define LS_DEFAULT_MET	ls_end.ule_switch.sws_default_met
 | 
						|
 | 
						|
/* describes a branch in the program, with its local idfs */
 | 
						|
struct state {
 | 
						|
	struct state *next;		/* only used by memory allocator */
 | 
						|
	struct auto_def *st_auto_list;
 | 
						|
	int st_notreached;		/* set if not reached */
 | 
						|
	int st_warned;			/* set if warning issued */
 | 
						|
};
 | 
						|
 | 
						|
/* ALLOCDEF "state" 15 */
 | 
						|
 | 
						|
/* describes the state of a local idf in a given branch of the program */
 | 
						|
struct auto_def {
 | 
						|
	struct auto_def *next;
 | 
						|
	struct idf *ad_idf;
 | 
						|
	struct def *ad_def;
 | 
						|
	int ad_used;
 | 
						|
	int ad_set;
 | 
						|
	int ad_maybe_set;
 | 
						|
};
 | 
						|
 | 
						|
/* ALLOCDEF "auto_def" 20 */
 | 
						|
 | 
						|
/* describes the state of an idf during expression evaluation */
 | 
						|
struct expr_state {			/*actually concerns idfs only */
 | 
						|
	struct expr_state *next;
 | 
						|
	struct idf *es_idf;		/* the idf with its offset */
 | 
						|
	arith es_offset;
 | 
						|
	int es_used;			/* value has been used */
 | 
						|
	int es_referred;		/* address has been taken */
 | 
						|
	int es_set;			/* has been assigned to */
 | 
						|
};
 | 
						|
 | 
						|
/* ALLOCDEF "expr_state" 20 */
 | 
						|
 |