From 0c0395ef24091518c34fc04738cedae647e0aaa9 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <error27@gmail.com>
Date: Wed, 11 Feb 2009 15:55:51 +0300
Subject: [PATCH] Remove a state from it's ->pools when set_state() is called.

There are old implied pools out there.  When we set the state all the
things that were implied previously are not implied now.

if (foo) {
    bar = 1;
}
bar = 0;

non null foo doesn't implied bar == 1 anymore.

Signed-off-by: Dan Carpenter <error27@gmail.com>
---
 smatch_slist.c  | 18 ++++++++++++++++++
 smatch_slist.h  |  1 +
 smatch_states.c | 26 +++++++++++++++-----------
 3 files changed, 34 insertions(+), 11 deletions(-)

diff --git a/smatch_slist.c b/smatch_slist.c
index 36cc13c8..2ef6c3a1 100644
--- a/smatch_slist.c
+++ b/smatch_slist.c
@@ -478,6 +478,24 @@ void merge_slist(struct state_list **to, struct state_list *slist)
 }
 
 /*
+ * If you call set_state() then you need to remove
+ * the state from any pools it's in.  Just setting ->pools
+ * to NULL isn't enough.
+ */
+void remove_from_pools(struct sm_state *old)
+{
+	struct state_list *slist;
+
+	if (!old)
+		return;
+
+	FOR_EACH_PTR(old->pools, slist) {
+		delete_state_slist(&slist, old->name, old->owner, old->sym);
+	} END_FOR_EACH_PTR(slist);
+}
+
+
+/*
  * filter() is used to find what states are the same across
  * a series of slists.
  * It takes a **slist and a *filter.  
diff --git a/smatch_slist.h b/smatch_slist.h
index d192dc13..09533261 100644
--- a/smatch_slist.h
+++ b/smatch_slist.h
@@ -74,6 +74,7 @@ struct smatch_state *get_state_stack(struct state_list_stack *stack, const char
 		    int owner, struct symbol *sym);
 
 void merge_slist(struct state_list **to, struct state_list *slist);
+void remove_from_pools(struct sm_state *old);
 void filter(struct state_list **slist, struct state_list *filter);
 void and_slist_stack(struct state_list_stack **slist_stack);
 
diff --git a/smatch_states.c b/smatch_states.c
index 0784aba4..15eb3d58 100644
--- a/smatch_states.c
+++ b/smatch_states.c
@@ -63,21 +63,24 @@ void __print_cur_slist()
 void set_state(const char *name, int owner, struct symbol *sym,
 	       struct smatch_state *state)
 {
+	struct sm_state *old;
+
 	if (!name)
 		return;
 	
+	old = __get_sm_state(name, owner, sym);
+
 	if (debug_states) {
-		struct smatch_state *s;
-		
-		s = get_state(name, owner, sym);
-		if (!s)
+		if (!old)
 			printf("%d new state. name='%s' owner=%d: %s\n", 
 			       get_lineno(), name, owner, show_state(state));
 		else
 			printf("%d state change name='%s' owner=%d: %s => %s\n",
-			       get_lineno(), name, owner, show_state(s),
-			       show_state(state));
+				get_lineno(), name, owner,
+				show_state(old->state), show_state(state));
 	}
+
+	remove_from_pools(old);
 	set_state_slist(&cur_slist, name, owner, sym, state);
 
 	if (cond_true_stack) {
@@ -135,15 +138,14 @@ void set_true_false_states(const char *name, int owner, struct symbol *sym,
 			   struct smatch_state *true_state,
 			   struct smatch_state *false_state)
 {
+	struct sm_state *old;
 	/* fixme.  save history */
 
+	old = __get_sm_state(name, owner, sym);
 	if (debug_states) {
-		struct smatch_state *tmp;
-
-		tmp = get_state(name, owner, sym);
 		SM_DEBUG("%d set_true_false '%s'.  Was %s.  Now T:%s F:%s\n",
-			 get_lineno(), name, show_state(tmp),
-			 show_state(true_state), show_state(false_state));
+			get_lineno(), name, (old?show_state(old->state):NULL),
+			show_state(true_state), show_state(false_state));
 	}
 
 	if (!cond_false_stack || !cond_true_stack) {
@@ -151,6 +153,8 @@ void set_true_false_states(const char *name, int owner, struct symbol *sym,
 		return;
 	}
 
+	remove_from_pools(old);
+
 	if (true_state) {
 		set_state_slist(&cur_slist, name, owner, sym, true_state);
 		set_state_stack(&cond_true_stack, name, owner, sym, true_state);
-- 
2.11.4.GIT