/*
** Splint - annotation-assisted static program checker
** Copyright (C) 1994-2003 University of Virginia,
** Massachusetts Institute of Technology
**
** This program is free software; you can redistribute it and/or modify it
** under the terms of the GNU General Public License as published by the
** Free Software Foundation; either version 2 of the License, or (at your
** option) any later version.
**
** This program is distributed in the hope that it will be useful, but
** WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
** General Public License for more details.
**
** The GNU General Public License is available from http://www.gnu.org/ or
** the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
** MA 02111-1307, USA.
**
** For information on splint: info@splint.org
** To report a bug: splint-bug@splint.org
** For more information: http://www.splint.org
*/
/*
*
** constraintResolve.c
*/
/* #define DEBUGPRINT 1 */
# include <ctype.h> /* for isdigit */
# include "splintMacros.nf"
# include "basic.h"
# include "cgrammar.h"
# include "cgrammar_tokens.h"
# include "exprChecks.h"
# include "exprNodeSList.h"
/*@access constraint, exprNode @*/ /*!!! NO! Don't do this so recklessly - design your code more carefully so you don't need to! */
static constraint inequalitySubstitute (/*@returned@*/ constraint p_c, constraintList p_p);
static bool rangeCheck (arithType p_ar1, /*@observer@*/ constraintExpr p_expr1, arithType p_ar2, /*@observer@*/ constraintExpr p_expr2);
static constraint inequalitySubstituteUnsound (/*@returned@*/ constraint p_c, constraintList p_p);
static constraint inequalitySubstituteStrong (/*@returned@*/ constraint p_c, constraintList p_p);
static constraint constraint_searchandreplace (/*@returned@*/ constraint p_c, constraintExpr p_old, constraintExpr p_newExpr);
static constraint constraint_addOr (/*@returned@*/ constraint p_orig, /*@observer@*/ constraint p_orConstr);
static bool resolveOr (/*@temp@*/constraint p_c, /*@observer@*/ /*@temp@*/ constraintList p_list);
static /*@only@*/ constraintList reflectChangesEnsuresFree1 (/*@only@*/ constraintList p_pre2, constraintList p_post1);
/*@only@*/ constraintList constraintList_mergeEnsuresFreeFirst (constraintList list1, constraintList list2)
{
constraintList ret;
ret = constraintList_mergeEnsures (list1, list2);
constraintList_free(list1);
return ret;
}
/*@only@*/ constraintList constraintList_mergeEnsures (constraintList list1, constraintList list2)
{
constraintList ret;
constraintList temp;
llassert(constraintList_isDefined(list1) );
llassert(constraintList_isDefined(list2) );
DPRINTF(( message ("constraintList_mergeEnsures: list1 %s list2 %s",
constraintList_unparse(list1), constraintList_unparse(list2)
)));
ret = constraintList_fixConflicts (list1, list2);
ret = reflectChangesEnsuresFree1 (ret, list2);
temp = constraintList_subsumeEnsures (ret, list2);
constraintList_free(ret);
ret = temp;
temp = constraintList_subsumeEnsures (list2, ret);
temp = constraintList_addList (temp, ret);
constraintList_free(ret);
DPRINTF(( message ("constraintList_mergeEnsures: returning %s ",
constraintList_unparse(temp) )
));
return temp;
}
/*@only@*/ constraintList constraintList_mergeRequiresFreeFirst (/*@only@*/ constraintList list1, constraintList list2)
{
constraintList ret;
ret = constraintList_mergeRequires(list1, list2);
constraintList_free(list1);
return ret;
}
/*@only@*/ constraintList constraintList_mergeRequires (constraintList list1, constraintList list2)
{
constraintList ret;
constraintList temp;
DPRINTF((message ("constraintList_mergeRequires: merging %s and %s ", constraintList_unparse (list1), constraintList_unparse(list2) ) ) );
if (context_getFlag (FLG_REDUNDANTCONSTRAINTS) )
{
ret = constraintList_copy(list1);
ret = constraintList_addList(ret, list2);
return ret;
}
/* get constraints in list1 not satified by list2 */
temp = constraintList_reflectChanges(list1, list2);
DPRINTF((message ("constraintList_mergeRequires: temp = %s", constraintList_unparse(temp) ) ) );
/*get constraints in list2 not satified by temp*/
ret = constraintList_reflectChanges(list2, temp);
DPRINTF((message ("constraintList_mergeRequires: ret = %s", constraintList_unparse(ret) ) ) );
ret = constraintList_addListFree (ret, temp);
DPRINTF((message ("constraintList_mergeRequires: returning %s", constraintList_unparse(ret) ) ) );
return ret;
}
/* old name mergeResolve renamed for czech naming convention */
void exprNode_mergeResolve (exprNode parent, exprNode child1, exprNode child2)
{
constraintList temp, temp2;
DPRINTF((message ("magically merging constraint into parent:%s for", exprNode_unparse (parent) )) );
DPRINTF((message (" children: %s and %s", exprNode_unparse (child1), exprNode_unparse(child2) ) ) );
if (exprNode_isUndefined(parent) )
{
llassert (exprNode_isDefined(parent) );
return;
}
if (exprNode_isError (child1) || exprNode_isError(child2) )
{
if (exprNode_isError (child1) && !exprNode_isError(child2) )
{
constraintList_free(parent->requiresConstraints);
parent->requiresConstraints = constraintList_copy (child2->requiresConstraints);
constraintList_free(parent->ensuresConstraints);
parent->ensuresConstraints = constraintList_copy (child2->ensuresConstraints);
DPRINTF((message ("Copied child constraints: pre: %s and post: %s",
constraintList_unparse( child2->requiresConstraints),
constraintList_unparse (child2->ensuresConstraints)
)
));
return;
}
else
{
llassert(exprNode_isError(child2) );
return;
}
}
llassert(!exprNode_isError (child1) && ! exprNode_isError(child2) );
DPRINTF((message ("Child constraints are %s %s and %s %s",
constraintList_unparse (child1->requiresConstraints),
constraintList_unparse (child1->ensuresConstraints),
constraintList_unparse (child2->requiresConstraints),
constraintList_unparse (child2->ensuresConstraints)
) ) );
constraintList_free(parent->requiresConstraints);
parent->requiresConstraints = constraintList_copy (child1->requiresConstraints);
if ( context_getFlag (FLG_ORCONSTRAINT) )
temp = constraintList_reflectChangesOr (child2->requiresConstraints, child1->ensuresConstraints);
else
temp = constraintList_reflectChanges(child2->requiresConstraints, child1->ensuresConstraints);
temp2 = constraintList_mergeRequires (parent->requiresConstraints, temp);
constraintList_free(parent->requiresConstraints);
constraintList_free(temp);
parent->requiresConstraints = temp2;
DPRINTF((message ("Parent requires constraints are %s ",
constraintList_unparse (parent->requiresConstraints)
) ) );
constraintList_free(parent->ensuresConstraints);
parent->ensuresConstraints = constraintList_mergeEnsures(child1->ensuresConstraints,
child2->ensuresConstraints);
DPRINTF((message ("Parent constraints are %s and %s ",
constraintList_unparse (parent->requiresConstraints),
constraintList_unparse (parent->ensuresConstraints)
) ) );
}
/*@only@*/ constraintList constraintList_subsumeEnsures (constraintList list1, constraintList list2)
{
constraintList ret;
ret = constraintList_makeNew();
constraintList_elements (list1, el)
{
DPRINTF ((message ("Examining %s", constraint_unparse (el) ) ) );
if (!constraintList_resolve (el, list2) )
{
constraint temp;
temp = constraint_copy(el);
ret = constraintList_add (ret, temp);
}
else
{
DPRINTF ((message ("Subsuming %s", constraint_unparse (el) ) ) );
}
} end_constraintList_elements;
return ret;
}
/*used to be reflectChangesFreePre renamed for Czech naming conventino*/
/* tries to resolve constraints in list pre2 using post1 */
/*@only@*/ constraintList constraintList_reflectChangesFreePre (/*@only@*/ constraintList pre2, /*@observer@*/ constraintList post1)
{
constraintList ret;
ret = constraintList_reflectChanges(pre2, post1);
constraintList_free (pre2);
return ret;
}
/* tries to resolve constraints in list pre2 using post1 */
static /*@only@*/ constraintList reflectChangesNoOr (/*@observer@*/ /*@temp@*/ constraintList pre2, /*@observer@*/ /*@temp@*/ constraintList post1)
{
constraintList ret;
constraint temp;
constraint temp2;
llassert (! context_getFlag (FLG_ORCONSTRAINT) );
ret = constraintList_makeNew();
DPRINTF((message ("reflectChanges: lists %s and %s", constraintList_unparse(pre2), constraintList_unparse(post1) )));
constraintList_elements (pre2, el)
{
if (!constraintList_resolve (el, post1) )
{
temp = constraint_substitute (el, post1);
if (!constraintList_resolve (temp, post1) )
{
/* try inequality substitution
the inequality substitution may cause us to lose information
so we don't want to store the result but we do it anyway
*/
temp2 = constraint_copy (temp);
temp2 = inequalitySubstitute (temp2, post1);
if (!constraintList_resolve (temp2, post1) )
{
temp2 = inequalitySubstituteUnsound (temp2, post1);
if (!constraintList_resolve (temp2, post1) )
ret = constraintList_add (ret, temp2);
else
constraint_free(temp2);
}
else
{
constraint_free(temp2);
}
}
constraint_free(temp);
}
} end_constraintList_elements;
DPRINTF((message ("reflectChanges: returning %s", constraintList_unparse(ret) ) ) );
return ret;
}
/* tries to resolve constraints in list pre2 using post1 */
/*@only@*/ constraintList constraintList_reflectChanges(/*@observer@*/ constraintList pre2, /*@observer@*/ constraintList post1)
{
constraintList temp;
if ( context_getFlag (FLG_ORCONSTRAINT) )
temp = constraintList_reflectChangesOr (pre2, post1);
else
temp = reflectChangesNoOr(pre2, post1);
return temp;
}
static constraint constraint_addOr (/*@returned@*/ constraint orig, /*@observer@*/ constraint orConstr)
{
constraint c;
llassert(constraint_isDefined(orig) );
c = orig;
DPRINTF((message("constraint_addor: oring %s onto %s", constraint_unparseOr(orConstr), constraint_unparseOr(orig) ) ));
while (c->or != NULL)
{
c = c->or;
}
c->or = constraint_copy(orConstr);
DPRINTF((message("constraint_addor: returning %s",constraint_unparseOr(orig) ) ));
return orig;
}
static bool resolveOr ( /*@temp@*/ constraint c, /*@observer@*/ /*@temp@*/ constraintList list)
{
constraint temp;
int numberOr;
numberOr = 0;
llassert(constraint_isDefined(c) );
DPRINTF(( message("resolveOr: constraint %s and list %s", constraint_unparseOr(c), constraintList_unparse(list) ) ));
temp = c;
do
{
if (constraintList_resolve (temp, list) )
return TRUE;
temp = temp->or;
numberOr++;
llassert(numberOr <= 10);
}
while (constraint_isDefined(temp));
return FALSE;
}
/*This is a "helper" function for doResolveOr */
static /*@only@*/ constraint doResolve (/*@only@*/ constraint c, constraintList post1, bool * resolved)
{
constraint temp;
llassert(constraint_isDefined (c ) );
DPRINTF((message("doResolve:: call on constraint c = : %q and constraintList %q",
constraint_unparseOr(c), constraintList_unparse(post1)
)
));
if (!resolveOr (c, post1) )
{
temp = constraint_substitute (c, post1);
DPRINTF((message("doResolve:: after substitute temp is %q",
constraint_unparseOr(temp)
)
));
if (!resolveOr (temp, post1) )
{
/* try inequality substitution */
constraint temp2;
/* the inequality substitution may cause us to lose information
so we don't want to store the result but we do anyway
*/
temp2 = constraint_copy (c);
temp2 = inequalitySubstitute (temp2, post1);
if (!resolveOr (temp2, post1) )
{
constraint temp3;
temp3 = constraint_copy(temp2);
temp3 = inequalitySubstituteStrong (temp3, post1);
if (!resolveOr (temp3, post1) )
{
temp2 = inequalitySubstituteUnsound (temp2, post1);
if (!resolveOr (temp2, post1) )
{
if (!constraint_same (temp, temp2) )
{
/* drl added 8/28/2002*/
/*make sure that the information from
a post condition like i = i + 1 is transfered
*/
constraint tempSub;
tempSub = constraint_substitute (temp2, post1);
DPRINTF((
message("doResolve: adding %s ",
constraint_unparseOr(tempSub)
)
));
DPRINTF((
message("doResolve: not adding %s ",
constraint_unparseOr(temp2)
)
));
temp = constraint_addOr (temp, tempSub);
constraint_free(tempSub);
}
if (!constraint_same (temp, temp3) && !constraint_same (temp3, temp2) )
{
/* drl added 8/28/2002*/
/*make sure that the information from
a post condition like i = i + 1 is transfered
*/
constraint tempSub;
tempSub = constraint_substitute (temp3, post1);
DPRINTF((
message("doResolve: adding %s ",
constraint_unparseOr(tempSub)
)
));
DPRINTF((
message("doResolve: not adding %s ",
constraint_unparseOr(temp3)
)
));
temp = constraint_addOr (temp, tempSub);
constraint_free(tempSub);
}
*resolved = FALSE;
constraint_free(temp2);
constraint_free(temp3);
constraint_free(c);
return temp;
}
constraint_free(temp2);
constraint_free(temp3);
}
else
{
constraint_free(temp2);
constraint_free(temp3);
}
}
else
{
constraint_free(temp2);
}
}
constraint_free(temp);
}
constraint_free(c);
*resolved = TRUE;
return NULL;
}
static /*@only@*/ constraint doResolveOr (/*@observer@*/ /*@temp@*/ constraint c, constraintList post1, /*@out@*/bool * resolved)
{
constraint ret;
constraint next;
constraint curr;
DPRINTF(( message("doResolveOr: constraint %s and list %s", constraint_unparseOr(c), constraintList_unparse(post1) ) ));
*resolved = FALSE;
llassert(constraint_isDefined(c) );
ret = constraint_copy(c);
llassert(constraint_isDefined(ret) );
if (constraintList_isEmpty(post1) )
{
return ret;
}
next = ret->or;
ret->or = NULL;
ret = doResolve (ret, post1, resolved);
if (*resolved)
{
if (next != NULL)
constraint_free(next);
/*we don't need to free ret when resolved is false because ret is null*/
llassert(ret == NULL);
return NULL;
}
while (next != NULL)
{
curr = next;
next = curr->or;
curr->or = NULL;
curr = doResolve (curr, post1, resolved);
if (*resolved)
{
/* curr is null so we don't try to free it*/
llassert(curr == NULL);
if (next != NULL)
constraint_free(next);
constraint_free(ret);
return NULL;
}
ret = constraint_addOr (ret, curr);
constraint_free(curr);
}
DPRINTF(( message("doResolveOr: returning ret = %s", constraint_unparseOr(ret) ) ));
return ret;
}
/* tries to resolve constraints in list pr2 using post1 */
/*@only@*/ constraintList constraintList_reflectChangesOr (constraintList pre2, constraintList post1)
{
bool resolved;
constraintList ret;
constraint temp;
ret = constraintList_makeNew();
DPRINTF((message ("constraintList_reflectChangesOr: lists %s and %s", constraintList_unparse(pre2), constraintList_unparse(post1) )));
constraintList_elements (pre2, el)
{
temp = doResolveOr (el, post1, &resolved);
if (!resolved)
{
ret = constraintList_add(ret, temp);
}
else
{
/* we don't need to free temp when
resolved is false because temp is null */
llassert(temp == NULL);
}
} end_constraintList_elements;
DPRINTF((message ("constraintList_reflectChangesOr: returning %s", constraintList_unparse(ret) ) ) );
return ret;
}
static /*@only@*/ constraintList reflectChangesEnsures (/*@observer@*/ constraintList pre2, constraintList post1)
{
constraintList ret;
constraint temp;
ret = constraintList_makeNew();
constraintList_elements (pre2, el)
{
if (!constraintList_resolve (el, post1) )
{
temp = constraint_substitute (el, post1);
llassert (temp != NULL);
if (!constraintList_resolve (temp, post1) )
ret = constraintList_add (ret, temp);
else
constraint_free(temp);
}
else
{
DPRINTF ((message ("Resolved away %s ", constraint_unparse(el) ) ) );
}
} end_constraintList_elements;
return ret;
}
static /*@only@*/ constraintList reflectChangesEnsuresFree1 (/*@only@*/ constraintList pre2, constraintList post1)
{
constraintList ret;
ret = reflectChangesEnsures (pre2, post1);
constraintList_free(pre2);
return ret;
}
static bool constraint_conflict (constraint c1, constraint c2)
{
if (!constraint_isDefined(c1) || !constraint_isDefined(c2))
{
return FALSE;
}
if (constraintExpr_similar (c1->lexpr, c2->lexpr))
{
if (c1->ar == EQ)
if (c1->ar == c2->ar)
{
DPRINTF (("%s conflicts with %s", constraint_unparse (c1), constraint_unparse (c2)));
return TRUE;
}
}
/* This is a slight kludge to prevent circular constraints like
strlen(str) == maxRead(s) + strlen(str);
*/
/*this code is functional but it may be worth cleaning up at some point. */
if (c1->ar == EQ)
if (c1->ar == c2->ar)
{
if (constraintExpr_search (c1->lexpr, c2->expr) )
if (constraintExpr_isTerm(c1->lexpr) )
{
constraintTerm term;
term = constraintExpr_getTerm(c1->lexpr);
if (constraintTerm_isExprNode(term) )
{
DPRINTF ((message ("%s conflicts with %s ", constraint_unparse (c1), constraint_unparse(c2) ) ) );
return TRUE;
}
}
}
if (constraint_tooDeep(c1) || constraint_tooDeep(c2) )
{
DPRINTF ((message ("%s conflicts with %s (constraint is too deep", constraint_unparse (c1), constraint_unparse(c2) ) ) );
return TRUE;
}
DPRINTF ((message ("%s doesn't conflict with %s ", constraint_unparse (c1), constraint_unparse(c2) ) ) );
return FALSE;
}
static void constraint_fixConflict (/*@temp@*/ constraint good, /*@temp@*/ /*@observer@*/ constraint conflicting) /*@modifies good@*/
{
llassert(constraint_isDefined(conflicting) );
if (conflicting->ar == EQ)
{
llassert (constraint_isDefined(good));
DPRINTF (("Replacing here!"));
good->expr = constraintExpr_searchandreplace (good->expr, conflicting->lexpr, conflicting->expr);
good = constraint_simplify (good);
}
}
static bool conflict (constraint c, constraintList list)
{
constraintList_elements (list, el)
{
if ( constraint_conflict(el, c) )
{
constraint_fixConflict (el, c);
return TRUE;
}
} end_constraintList_elements;
return FALSE;
}
/*
check if constraint in list1 conflicts with constraints in List2. If so we
remove form list1 and change list2.
*/
constraintList constraintList_fixConflicts (constraintList list1, constraintList list2)
{
constraintList ret;
ret = constraintList_makeNew();
llassert(constraintList_isDefined(list1) );
constraintList_elements (list1, el)
{
if (! conflict (el, list2) )
{
constraint temp;
temp = constraint_copy(el);
ret = constraintList_add (ret, temp);
}
} end_constraintList_elements;
return ret;
}
/*returns true if constraint post satisfies cosntriant pre */
static bool constraintResolve_satisfies (constraint pre, constraint post)
{
if (!constraint_isDefined (pre))
{
return TRUE;
}
if (!constraint_isDefined(post))
{
return FALSE;
}
if (constraint_isAlwaysTrue (pre))
return TRUE;
if (!constraintExpr_similar (pre->lexpr, post->lexpr) )
{
return FALSE;
}
if (constraintExpr_isUndefined(post->expr))
{
llassert(FALSE);
return FALSE;
}
return rangeCheck (pre->ar, pre->expr, post->ar, post->expr);
}
bool constraintList_resolve (/*@temp@*/ /*@observer@*/ constraint c,
/*@temp@*/ /*@observer@*/ constraintList p)
{
DPRINTF (("[resolve] Trying to resolve constraint: %s using %s",
constraint_unparse (c),
constraintList_unparse (p)));
constraintList_elements (p, el)
{
if (constraintResolve_satisfies (c, el))
{
DPRINTF (("constraintList_resolve: %s satifies %s",
constraint_unparse (el), constraint_unparse (c)));
return TRUE;
}
DPRINTF (("constraintList_resolve: %s does not satify %s\n ",
constraint_unparse (el), constraint_unparse (c)));
}
end_constraintList_elements;
DPRINTF (("No constraints satify: %s", constraint_unparse (c)));
return FALSE;
}
static bool arithType_canResolve (arithType ar1, arithType ar2)
{
switch (ar1)
{
case GTE:
case GT:
if ((ar2 == GT) || (ar2 == GTE) || (ar2 == EQ))
{
return TRUE;
}
break;
case EQ:
if (ar2 == EQ)
return TRUE;
break;
case LT:
case LTE:
if ((ar2 == LT) || (ar2 == LTE) || (ar2 == EQ))
return TRUE;
break;
default:
return FALSE;
}
return FALSE;
}
/*checks for the case expr2 == sizeof buf1 and buf1 is a fixed array*/
static bool sizeofBufComp(constraintExpr buf1, constraintExpr expr2)
{
constraintTerm ct;
exprNode e, t;
sRef s1, s2;
llassert(constraintExpr_isDefined(buf1) && constraintExpr_isDefined(expr2) );
/*@access constraintExpr@*/
if ((expr2->kind != term) && (buf1->kind != term) )
return FALSE;
ct = constraintExprData_termGetTerm(expr2->data);
if (!constraintTerm_isExprNode(ct) )
return FALSE;
e = constraintTerm_getExprNode(ct);
llassert (exprNode_isDefined(e));
if (! (exprNode_isDefined(e)))
return FALSE;
if (e->kind != XPR_SIZEOF)
return FALSE;
t = exprData_getSingle (e->edata);
s1 = exprNode_getSref (t);
s2 = constraintTerm_getsRef(constraintExprData_termGetTerm(buf1->data) );
/*drl this may be the wronge thing to test for but this
seems to work correctly*/
if (sRef_similarRelaxed(s1, s2) || sRef_sameName (s1, s2) )
{
/* origly checked that ctype_isFixedArray(sRef_getType(s2)) but
removed that test */
return TRUE;
}
return FALSE;
}
/* look for the special case of
maxSet(buf) >= sizeof(buf) - 1
*/
/*drl eventually it would be good to check that
buf is of type char.*/
static bool sizeOfMaxSet( /*@observer@*/ /*@temp@*/ constraint c)
{
constraintExpr l, r, buf1, buf2, con;
DPRINTF(( message("sizeOfMaxSet: checking %s ", constraint_unparse(c) )
));
llassert (constraint_isDefined(c) );
l = c->lexpr;
r = c->expr;
if (!((c->ar == EQ) || (c->ar == GTE) || (c->ar == LTE) ) )
return FALSE;
llassert (constraintExpr_isDefined(l) );
llassert (constraintExpr_isDefined(r) );
/*check if the constraintExpr is MaxSet(buf) */
if (l->kind == unaryExpr)
{
if (constraintExprData_unaryExprGetOp(l->data) == MAXSET)
{
buf1 = constraintExprData_unaryExprGetExpr(l->data);
}
else
return FALSE;
}
else
return FALSE;
if (r->kind != binaryexpr)
return FALSE;
buf2 = constraintExprData_binaryExprGetExpr1(r->data);
con = constraintExprData_binaryExprGetExpr2(r->data);
if (constraintExprData_binaryExprGetOp(r->data) == BINARYOP_MINUS)
{
if (constraintExpr_canGetValue(con) )
{
long i;
i = constraintExpr_getValue(con);
if (i != 1)
{
return FALSE;
}
}
else
return FALSE;
}
if (constraintExprData_binaryExprGetOp(r->data) == BINARYOP_PLUS)
{
if (constraintExpr_canGetValue(con) )
{
long i;
i = constraintExpr_getValue(con);
if (i != -1)
{
return FALSE;
}
}
else
return FALSE;
}
if (sizeofBufComp(buf1, buf2))
{
return TRUE;
}
else
{
return FALSE;
}
}
/*@noaccess constraintExpr@*/
/* We look for constraint which are tautologies */
bool constraint_isAlwaysTrue (/*@observer@*/ /*@temp@*/ constraint c)
{
constraintExpr l, r;
bool rHasConstant;
int rConstant;
llassert (constraint_isDefined(c) );
l = c->lexpr;
r = c->expr;
DPRINTF(( message("constraint_IsAlwaysTrue:examining %s", constraint_unparse(c) ) ));
if (sizeOfMaxSet(c) )
return TRUE;
if (constraintExpr_canGetValue(l) && constraintExpr_canGetValue(r) )
{
int cmp;
cmp = constraintExpr_compare (l, r);
switch (c->ar)
{
case EQ:
return (cmp == 0);
case GT:
return (cmp > 0);
case GTE:
return (cmp >= 0);
case LTE:
return (cmp <= 0);
case LT:
return (cmp < 0);
default:
BADEXIT;
/*@notreached@*/
break;
}
}
if (constraintExpr_similar (l,r))
{
switch (c->ar)
{
case EQ:
case GTE:
case LTE:
return TRUE;
case GT:
case LT:
break;
default:
BADEXIT;
/*@notreached@*/
break;
}
}
l = constraintExpr_copy (c->lexpr);
r = constraintExpr_copy (c->expr);
r = constraintExpr_propagateConstants (r, &rHasConstant, &rConstant);
if (constraintExpr_similar (l,r) && (rHasConstant ) )
{
DPRINTF(( message("constraint_IsAlwaysTrue: after removing constants %s and %s are similar", constraintExpr_unparse(l), constraintExpr_unparse(r) ) ));
DPRINTF(( message("constraint_IsAlwaysTrue: rconstant is %d", rConstant ) ));
constraintExpr_free(l);
constraintExpr_free(r);
switch (c->ar)
{
case EQ:
return (rConstant == 0);
case LT:
return (rConstant > 0);
case LTE:
return (rConstant >= 0);
case GTE:
return (rConstant <= 0);
case GT:
return (rConstant < 0);
default:
BADEXIT;
/*@notreached@*/
break;
}
}
else
{
constraintExpr_free(l);
constraintExpr_free(r);
DPRINTF(( message("Constraint %s is not always true", constraint_unparse(c) ) ));
return FALSE;
}
BADEXIT;
}
static bool rangeCheck (arithType ar1, /*@observer@*/ constraintExpr expr1, arithType ar2, /*@observer@*/ constraintExpr expr2)
{
DPRINTF (("Doing range check %s and %s",
constraintExpr_unparse (expr1), constraintExpr_unparse (expr2)));
if (!arithType_canResolve (ar1, ar2))
return FALSE;
switch (ar1)
{
case GTE:
if (constraintExpr_similar (expr1, expr2) )
return TRUE;
/*@fallthrough@*/
case GT:
if (! (constraintExpr_canGetValue (expr1) &&
constraintExpr_canGetValue (expr2) ) )
{
constraintExpr e1, e2;
bool p1, p2;
int const1, const2;
e1 = constraintExpr_copy(expr1);
e2 = constraintExpr_copy(expr2);
e1 = constraintExpr_propagateConstants (e1, &p1, &const1);
e2 = constraintExpr_propagateConstants (e2, &p2, &const2);
if (p1 || p2)
{
if (!p1)
const1 = 0;
if (!p2)
const2 = 0;
if (const1 <= const2)
if (constraintExpr_similar (e1, e2) )
{
constraintExpr_free(e1);
constraintExpr_free(e2);
return TRUE;
}
}
DPRINTF(("Can't Get value"));
constraintExpr_free(e1);
constraintExpr_free(e2);
return FALSE;
}
if (constraintExpr_compare (expr2, expr1) >= 0)
return TRUE;
return FALSE;
case EQ:
if (constraintExpr_similar (expr1, expr2) )
return TRUE;
return FALSE;
case LTE:
if (constraintExpr_similar (expr1, expr2) )
return TRUE;
/*@fallthrough@*/
case LT:
if (! (constraintExpr_canGetValue (expr1) &&
constraintExpr_canGetValue (expr2) ) )
{
constraintExpr e1, e2;
bool p1, p2;
int const1, const2;
e1 = constraintExpr_copy(expr1);
e2 = constraintExpr_copy(expr2);
e1 = constraintExpr_propagateConstants (e1, &p1, &const1);
e2 = constraintExpr_propagateConstants (e2, &p2, &const2);
if (p1 || p2)
{
if (!p1)
const1 = 0;
if (!p2)
const2 = 0;
if (const1 >= const2)
if (constraintExpr_similar (e1, e2) )
{
constraintExpr_free(e1);
constraintExpr_free(e2);
return TRUE;
}
}
constraintExpr_free(e1);
constraintExpr_free(e2);
DPRINTF(("Can't Get value"));
return FALSE;
}
if (constraintExpr_compare (expr2, expr1) <= 0)
return TRUE;
return FALSE;
default:
llcontbug((message("Unhandled case in switch: %q", arithType_print(ar1) ) ) );
}
BADEXIT;
}
static constraint constraint_searchandreplace (/*@returned@*/ constraint c, constraintExpr old, constraintExpr newExpr)
{
llassert (constraint_isDefined(c));
DPRINTF (("Starting replace lexpr [%p]: %s < %s ==> %s > in %s", c,
constraintExpr_unparse (c->lexpr),
constraintExpr_unparse (old), constraintExpr_unparse (newExpr),
constraint_unparse (c)));
c->lexpr = constraintExpr_searchandreplace (c->lexpr, old, newExpr);
DPRINTF (("Finished replace lexpr [%p]: %s", c, constraintExpr_unparse (c->lexpr)));
c->expr = constraintExpr_searchandreplace (c->expr, old, newExpr);
return c;
}
bool constraint_search (constraint c, constraintExpr old) /*@*/
{
bool ret;
ret = FALSE;
llassert (constraint_isDefined (c));
ret = constraintExpr_search (c->lexpr, old);
ret = ret || constraintExpr_search (c->expr, old);
return ret;
}
/* adjust file locs and stuff */
static constraint constraint_adjust (/*@returned@*/ constraint substitute, /*@observer@*/ constraint old)
{
fileloc loc1, loc2, loc3;
DPRINTF ((message("Start adjust on %s and %s", constraint_unparse(substitute),
constraint_unparse(old))
));
llassert(constraint_isDefined(substitute));
llassert(constraint_isDefined(old));
loc1 = constraint_getFileloc (old);
loc2 = constraintExpr_loc (substitute->lexpr);
loc3 = constraintExpr_loc (substitute->expr);
/* special case of an equality that "contains itself" */
if (constraintExpr_search (substitute->expr, substitute->lexpr) )
if (fileloc_closer (loc1, loc3, loc2))
{
constraintExpr temp;
DPRINTF ((message("Doing adjust on %s", constraint_unparse(substitute) )
));
temp = substitute->lexpr;
substitute->lexpr = substitute->expr;
substitute->expr = temp;
substitute = constraint_simplify(substitute);
}
fileloc_free (loc1);
fileloc_free (loc2);
fileloc_free (loc3);
return substitute;
}
/* If function preforms substitutes based on inequality
It uses the rule x >= y && b < y ===> x >= b + 1
Warning this is sound but throws out information
*/
constraint inequalitySubstitute (/*@returned@*/ constraint c, constraintList p)
{
llassert(constraint_isDefined(c) );
if (c->ar != GTE)
return c;
constraintList_elements (p, el)
{
llassert(constraint_isDefined(el) );
if ((el->ar == LT ) )
{
constraintExpr temp2;
if (constraintExpr_same (el->expr, c->expr) )
{
DPRINTF((message ("inequalitySubstitute Replacing %q in %q with %q",
constraintExpr_print (c->expr),
constraint_unparse (c),
constraintExpr_print (el->expr) )
));
temp2 = constraintExpr_copy (el->lexpr);
constraintExpr_free(c->expr);
c->expr = constraintExpr_makeIncConstraintExpr (temp2);
}
}
}
end_constraintList_elements;
c = constraint_simplify(c);
return c;
}
/* drl7x 7/26/001
THis function is like inequalitySubstitute but it adds the rule
added the rules x >= y && y <= b ===> x >= b
x >= y && y < b ===> x >= b + 1
This is sound but sonce it throws out additional information it should only one used
if we're oring constraints.
*/
static constraint inequalitySubstituteStrong (/*@returned@*/ constraint c, constraintList p)
{
DPRINTF (( message ("inequalitySubstituteStrong examining substituting for %q", constraint_unparse(c) ) ));
llassert(constraint_isDefined(c) );
if (! (constraint_isDefined(c) ) )
{
return c;
}
if (c->ar != GTE)
return c;
DPRINTF (( message ("inequalitySubstituteStrong examining substituting for %q with %q",
constraint_unparse(c), constraintList_unparse(p) ) ));
constraintList_elements (p, el)
{
DPRINTF (( message ("inequalitySubstituteStrong examining substituting %s on %s", constraint_unparse(el), constraint_unparse(c) ) ));
llassert(constraint_isDefined(el) );
if ((el->ar == LT ) || (el->ar == LTE ) )
{
constraintExpr temp2;
if (constraintExpr_same (el->lexpr, c->expr) )
{
DPRINTF((message ("inequalitySubstitute Replacing %s in %s with %s",
constraintExpr_print (c->expr),
constraint_unparse (c),
constraintExpr_print (el->expr) )
));
temp2 = constraintExpr_copy (el->expr);
constraintExpr_free(c->expr);
if ((el->ar == LTE ) )
{
c->expr = temp2;
}
else
{
c->expr = constraintExpr_makeIncConstraintExpr (temp2);
}
}
}
}
end_constraintList_elements;
c = constraint_simplify(c);
return c;
}
/* This function performs substitutions based on the rule:
for a constraint of the form expr1 >= expr2; a < b =>
a = b -1 for all a in expr1. This will work in most cases.
Like inequalitySubstitute we're throwing away some information
*/
static constraint inequalitySubstituteUnsound (/*@returned@*/ constraint c, constraintList p)
{
DPRINTF (( message ("Doing inequalitySubstituteUnsound " ) ));
llassert(constraint_isDefined(c) );
if (c->ar != GTE)
return c;
constraintList_elements (p, el)
{
llassert(constraint_isDefined(el) );
DPRINTF (( message ("inequalitySubstituteUnsound examining substituting %s on %s", constraint_unparse(el), constraint_unparse(c) ) ));
if (( el->ar == LTE) || (el->ar == LT) )
{
constraintExpr temp2;
temp2 = constraintExpr_copy (el->expr);
if (el->ar == LT)
temp2 = constraintExpr_makeDecConstraintExpr (temp2);
DPRINTF((message ("Replacing %s in %s with %s",
constraintExpr_print (el->lexpr),
constraintExpr_print (c->lexpr),
constraintExpr_print (temp2) ) ));
c->lexpr = constraintExpr_searchandreplace (c->lexpr, el->lexpr, temp2);
constraintExpr_free(temp2);
}
}
end_constraintList_elements;
c = constraint_simplify(c);
return c;
}
/*@only@*/ constraint constraint_substitute (/*@observer@*/ /*@temp@*/ constraint c, constraintList p)
{
constraint ret = constraint_copy (c);
constraintList_elements (p, el)
{
if (constraint_isDefined (el))
{
if ( el->ar == EQ)
if (!constraint_conflict (ret, el))
{
constraint temp = constraint_copy(el);
temp = constraint_adjust(temp, ret);
llassert(constraint_isDefined(temp) );
DPRINTF (("constraint_substitute :: Substituting in %s using %s",
constraint_unparse (ret), constraint_unparse (temp)));
ret = constraint_searchandreplace (ret, temp->lexpr, temp->expr);
DPRINTF (("constraint_substitute :: The new constraint is %s", constraint_unparse (ret)));;
constraint_free(temp);
}
}
}
end_constraintList_elements;
ret = constraint_simplify (ret);
DPRINTF(( message (" constraint_substitute :: The final new constraint is %s", constraint_unparse (ret) ) ));
return ret;
}
/*@only@*/ constraintList constraintList_substituteFreeTarget (/*@only@*/ constraintList target, /*@observer@*/ constraintList subList)
{
constraintList ret;
ret = constraintList_substitute (target, subList);
constraintList_free(target);
return ret;
}
/* we try to do substitutions on each constraint in target using the constraint in sublist*/
/*@only@*/ constraintList constraintList_substitute (constraintList target,/*2observer@*/ constraintList subList)
{
constraintList ret;
ret = constraintList_makeNew();
constraintList_elements(target, el)
{
constraint temp;
/* drl possible problem : warning make sure that a side effect is not expected */
temp = constraint_substitute(el, subList);
ret = constraintList_add (ret, temp);
}
end_constraintList_elements;
return ret;
}
static constraint constraint_solve (/*@returned@*/ constraint c)
{
llassert(constraint_isDefined(c) );
DPRINTF((message ("Solving %s\n", constraint_unparse(c) ) ) );
c->expr = constraintExpr_solveBinaryExpr (c->lexpr, c->expr);
DPRINTF((message ("Solved and got %s\n", constraint_unparse(c) ) ) );
return c;
}
static arithType flipAr (arithType ar)
{
switch (ar)
{
case LT:
return GT;
case LTE:
return GTE;
case EQ:
return EQ;
case GT:
return LT;
case GTE:
return LTE;
default:
llcontbug (message("unexpected value: case not handled"));
}
BADEXIT;
}
static constraint constraint_swapLeftRight (/*@returned@*/ constraint c)
{
constraintExpr temp;
llassert(constraint_isDefined(c) );
c->ar = flipAr (c->ar);
temp = c->lexpr;
c->lexpr = c->expr;
c->expr = temp;
DPRINTF(("Swaped left and right sides of constraint"));
return c;
}
constraint constraint_simplify ( /*@returned@*/ constraint c)
{
llassert(constraint_isDefined(c) );
DPRINTF(( message("constraint_simplify on %q ", constraint_unparse(c) ) ));
if (constraint_tooDeep(c))
{
DPRINTF(( message("constraint_simplify: constraint to complex aborting %q ", constraint_unparse(c) ) ));
return c;
}
c->lexpr = constraintExpr_simplify (c->lexpr);
c->expr = constraintExpr_simplify (c->expr);
if (constraintExpr_isBinaryExpr (c->lexpr) )
{
c = constraint_solve (c);
c->lexpr = constraintExpr_simplify (c->lexpr);
c->expr = constraintExpr_simplify (c->expr);
}
if (constraintExpr_isLit(c->lexpr) && (!constraintExpr_isLit(c->expr) ) )
{
c = constraint_swapLeftRight(c);
/*I don't think this will be an infinate loop*/
c = constraint_simplify(c);
}
DPRINTF(( message("constraint_simplify returning %q ", constraint_unparse(c) ) ));
return c;
}
/* returns true if fileloc for term1 is closer to file for term2 than term3*/
bool fileloc_closer (fileloc loc1, fileloc loc2, fileloc loc3)
{
if (!fileloc_isDefined (loc1) )
return FALSE;
if (!fileloc_isDefined (loc2) )
return FALSE;
if (!fileloc_isDefined (loc3) )
return TRUE;
if (fileloc_equal (loc2, loc3) )
return FALSE;
if (fileloc_equal (loc1, loc2) )
return TRUE;
if (fileloc_equal (loc1, loc3) )
return FALSE;
if ( fileloc_lessthan (loc1, loc2) )
{
if (fileloc_lessthan (loc2, loc3) )
{
llassert (fileloc_lessthan (loc1, loc3) );
return TRUE;
}
else
{
return FALSE;
}
}
if ( !fileloc_lessthan (loc1, loc2) )
{
if (!fileloc_lessthan (loc2, loc3) )
{
llassert (!fileloc_lessthan (loc1, loc3) );
return TRUE;
}
else
{
return FALSE;
}
}
llassert(FALSE);
return FALSE;
}
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