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fix at-most-1 constraint compiler bug

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2016-10-22 18:50:16 -07:00
parent bb6d826908
commit 23b9d3ef55
17 changed files with 369 additions and 62 deletions
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43
src/ast/rewriter/arith_rewriter.cpp
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@ -162,8 +162,8 @@ bool arith_rewriter::div_polynomial(expr * t, numeral const & g, const_treatment
}
bool arith_rewriter::is_bound(expr * arg1, expr * arg2, op_kind kind, expr_ref & result) {
numeral c;
if (!is_add(arg1) && is_numeral(arg2, c)) {
numeral b, c;
if (!is_add(arg1) && !m_util.is_mod(arg1) && is_numeral(arg2, c)) {
numeral a;
bool r = false;
expr * pp = get_power_product(arg1, a);
@ -193,6 +193,45 @@ bool arith_rewriter::is_bound(expr * arg1, expr * arg2, op_kind kind, expr_ref &
case EQ: result = m_util.mk_eq(pp, k); return true;
}
}
expr* t1, *t2;
bool is_int;
if (m_util.is_mod(arg2)) {
std::swap(arg1, arg2);
switch (kind) {
case LE: kind = GE; break;
case GE: kind = LE; break;
case EQ: break;
}
}
if (m_util.is_numeral(arg2, c, is_int) && is_int &&
m_util.is_mod(arg1, t1, t2) && m_util.is_numeral(t2, b, is_int) && !b.is_zero()) {
// mod x b <= c = false if c < 0, b != 0, true if c >= b, b != 0
if (c.is_neg()) {
switch (kind) {
case EQ:
case LE: result = m().mk_false(); return true;
case GE: result = m().mk_true(); return true;
}
}
if (c.is_zero() && kind == GE) {
result = m().mk_true();
return true;
}
if (c.is_pos() && c >= abs(b)) {
switch (kind) {
case LE: result = m().mk_true(); return true;
case EQ:
case GE: result = m().mk_false(); return true;
}
}
// mod x b <= b - 1
if (c + rational::one() == abs(b) && kind == LE) {
result = m().mk_true();
return true;
}
}
return false;
}