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reshuffle unicode support to use global parameter, and use bit-vectors on demand

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This commit is contained in:
Nikolaj Bjorner 2021-01-21 14:24:26 -08:00
parent fb48481860
commit dafee71500
11 changed files with 367 additions and 267 deletions
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3
src/ast/rewriter/seq_rewriter.cpp
View file

@ -719,6 +719,9 @@ br_status seq_rewriter::mk_app_core(func_decl * f, unsigned num_args, expr * con
SASSERT(num_args == 1);
st = mk_str_stoi(args[0], result);
break;
case OP_CHAR_LE:
case OP_CHAR_CONST:
break;
case _OP_STRING_CONCAT:
case _OP_STRING_PREFIX:
case _OP_STRING_SUFFIX:

126
src/ast/seq_decl_plugin.cpp
View file

@ -16,6 +16,7 @@ Author:
Revision History:
--*/
#include "util/gparams.h"
#include "ast/seq_decl_plugin.h"
#include "ast/arith_decl_plugin.h"
#include "ast/array_decl_plugin.h"
@ -47,7 +48,7 @@ static bool is_octal_digit(char ch, unsigned& d) {
return false;
}
static bool is_escape_char(char const *& s, unsigned& result) {
bool zstring::is_escape_char(char const *& s, unsigned& result) {
unsigned d1, d2, d3;
if (*s != '\\' || *(s + 1) == 0) {
return false;
@ -89,10 +90,8 @@ static bool is_escape_char(char const *& s, unsigned& result) {
result = 16*result + d1;
}
else if (*(s+3+i) == '}') {
#if !Z3_USE_UNICODE
if (result > 255)
if (result > 255 && !uses_unicode())
throw default_exception("unicode characters outside of byte range are not supported");
#endif
s += 4 + i;
return true;
}
@ -113,10 +112,8 @@ static bool is_escape_char(char const *& s, unsigned& result) {
break;
}
}
#if !Z3_USE_UNICODE
if (result > 255)
if (result > 255 && !uses_unicode())
throw default_exception("unicode characters outside of byte range are not supported");
#endif
s += 3 + i;
return true;
}
@ -177,14 +174,8 @@ zstring::zstring(char const* s) {
SASSERT(well_formed());
}
zstring::zstring(unsigned num_bits, bool const* ch) {
SASSERT(num_bits == 8); // TBD for unicode
unsigned n = 0;
for (unsigned i = 0; i < num_bits; ++i) {
n |= (((unsigned)ch[i]) << i);
}
m_buffer.push_back(n);
SASSERT(well_formed());
bool zstring::uses_unicode() const {
return gparams::get_value("unicode") == "true";
}
bool zstring::well_formed() const {
@ -402,7 +393,9 @@ seq_decl_plugin::seq_decl_plugin(): m_init(false),
m_char(nullptr),
m_reglan(nullptr),
m_has_re(false),
m_has_seq(false) {}
m_has_seq(false) {
m_unicode = gparams::get_value("unicode") == "true";
}
void seq_decl_plugin::finalize() {
for (psig* s : m_sigs) {
@ -623,11 +616,9 @@ void seq_decl_plugin::init() {
m_sigs[OP_SEQ_REPLACE_RE] = alloc(psig, m, "str.replace_re", 1, 3, seqAreAseqA, seqA);
m_sigs[OP_SEQ_REPLACE_ALL] = alloc(psig, m, "str.replace_all", 1, 3, seqAseqAseqA, seqA);
m_sigs[OP_STRING_CONST] = nullptr;
#if Z3_USE_UNICODE
m_sigs[OP_CHAR_CONST] = nullptr;
sort* charTcharT[2] = { m_char, m_char };
m_sigs[OP_CHAR_LE] = alloc(psig, m, "char.<=", 0, 2, charTcharT, boolT);
#endif
m_sigs[OP_CHAR_LE] = unicode() ? alloc(psig, m, "char.<=", 0, 2, charTcharT, boolT) : nullptr;
m_sigs[_OP_STRING_STRIDOF] = alloc(psig, m, "str.indexof", 0, 3, str2TintT, intT);
m_sigs[_OP_STRING_STRREPL] = alloc(psig, m, "str.replace", 0, 3, str3T, strT);
m_sigs[_OP_STRING_FROM_CHAR] = alloc(psig, m, "char", 1, 0, nullptr, strT);
@ -654,11 +645,10 @@ void seq_decl_plugin::init() {
void seq_decl_plugin::set_manager(ast_manager* m, family_id id) {
decl_plugin::set_manager(m, id);
bv_util bv(*m);
#if Z3_USE_UNICODE
m_char = m->mk_sort(symbol("Unicode"), sort_info(m_family_id, _CHAR_SORT, 0, nullptr));
#else
m_char = bv.mk_sort(8);
#endif
if (unicode())
m_char = m->mk_sort(symbol("Unicode"), sort_info(m_family_id, _CHAR_SORT, 0, nullptr));
else
m_char = bv.mk_sort(8);
m->inc_ref(m_char);
parameter param(m_char);
m_string = m->mk_sort(symbol("String"), sort_info(m_family_id, SEQ_SORT, 1, &param));
@ -692,10 +682,8 @@ sort * seq_decl_plugin::mk_sort(decl_kind k, unsigned num_parameters, parameter
}
return m.mk_sort(symbol("RegEx"), sort_info(m_family_id, RE_SORT, num_parameters, parameters));
}
#if Z3_USE_UNICODE
case _CHAR_SORT:
return m_char;
#endif
case _STRING_SORT:
return m_string;
case _REGLAN_SORT:
@ -941,7 +929,6 @@ func_decl * seq_decl_plugin::mk_func_decl(decl_kind k, unsigned num_parameters,
m_has_re = true;
return mk_str_fun(k, arity, domain, range, OP_SEQ_TO_RE);
#if Z3_USE_UNICODE
case OP_CHAR_LE:
if (arity == 2 && domain[0] == m_char && domain[1] == m_char) {
return m.mk_func_decl(m_sigs[k]->m_name, arity, domain, m.mk_bool_sort(), func_decl_info(m_family_id, k, 0, nullptr));
@ -955,7 +942,6 @@ func_decl * seq_decl_plugin::mk_func_decl(decl_kind k, unsigned num_parameters,
m.raise_exception("invalid character declaration");
}
return m.mk_const_decl(m_charc_sym, m_char, func_decl_info(m_family_id, OP_CHAR_CONST, num_parameters, parameters));
#endif
case OP_SEQ_IN_RE:
m_has_re = true;
@ -1046,14 +1032,15 @@ app* seq_decl_plugin::mk_string(zstring const& s) {
}
app* seq_decl_plugin::mk_char(unsigned u) {
#if Z3_USE_UNICODE
parameter param(u);
func_decl* f = m_manager->mk_const_decl(m_charc_sym, m_char, func_decl_info(m_family_id, OP_CHAR_CONST, 1, &param));
return m_manager->mk_const(f);
#else
UNREACHABLE();
return nullptr;
#endif
if (unicode()) {
parameter param(u);
func_decl* f = m_manager->mk_const_decl(m_charc_sym, m_char, func_decl_info(m_family_id, OP_CHAR_CONST, 1, &param));
return m_manager->mk_const(f);
}
else {
UNREACHABLE();
return nullptr;
}
}
@ -1117,13 +1104,11 @@ bool seq_decl_plugin::are_distinct(app* a, app* b) const {
if (is_app_of(b, m_family_id, OP_SEQ_EMPTY) &&
is_app_of(a, m_family_id, OP_SEQ_UNIT)) {
return true;
}
#if Z3_USE_UNICODE
if (is_app_of(a, m_family_id, OP_CHAR_CONST) &&
}
if (unicode() && is_app_of(a, m_family_id, OP_CHAR_CONST) &&
is_app_of(b, m_family_id, OP_CHAR_CONST)) {
return true;
}
#endif
return false;
}
@ -1160,6 +1145,17 @@ app* seq_util::str::mk_char(unsigned ch) const {
return u.mk_char(ch);
}
app* seq_util::str::mk_char_bit(expr* e, unsigned idx) {
return u.mk_char_bit(e, idx);
}
app* seq_util::mk_char_bit(expr* e, unsigned i) {
parameter params[2] = { parameter(symbol("char.bit")), parameter(i) };
sort* range = m.mk_bool_sort();
func_decl* f = m.mk_func_decl(get_family_id(), _OP_SEQ_SKOLEM, 2, params, 1, &e, range);
return m.mk_app(f, 1, &e);
}
bv_util& seq_util::bv() const {
if (!m_bv) m_bv = alloc(bv_util, m);
return *m_bv.get();
@ -1178,36 +1174,44 @@ unsigned seq_util::max_mul(unsigned x, unsigned y) const {
bool seq_util::is_const_char(expr* e, unsigned& c) const {
#if Z3_USE_UNICODE
return is_app_of(e, m_fid, OP_CHAR_CONST) && (c = to_app(e)->get_parameter(0).get_int(), true);
#else
rational r;
unsigned sz;
return bv().is_numeral(e, r, sz) && sz == 8 && r.is_unsigned() && (c = r.get_unsigned(), true);
#endif
if (seq.unicode()) {
return is_app_of(e, m_fid, OP_CHAR_CONST) && (c = to_app(e)->get_parameter(0).get_int(), true);
}
else {
rational r;
unsigned sz;
return bv().is_numeral(e, r, sz) && sz == 8 && r.is_unsigned() && (c = r.get_unsigned(), true);
}
}
bool seq_util::is_char_le(expr const* e) const {
if (seq.unicode())
return is_app_of(e, m_fid, OP_CHAR_LE);
else
return bv().is_bv_ule(e) && is_char(to_app(e)->get_arg(0));
}
app* seq_util::mk_char(unsigned ch) const {
#if Z3_USE_UNICODE
return seq.mk_char(ch);
#else
return bv().mk_numeral(rational(ch), 8);
#endif
if (seq.unicode())
return seq.mk_char(ch);
else
return bv().mk_numeral(rational(ch), 8);
}
app* seq_util::mk_le(expr* ch1, expr* ch2) const {
expr_ref _ch1(ch1, m), _ch2(ch2, m);
#if Z3_USE_UNICODE
expr* es[2] = { ch1, ch2 };
return m.mk_app(m_fid, OP_CHAR_LE, 2, es);
#else
rational r1, r2;
if (bv().is_numeral(ch1, r1) && bv().is_numeral(ch2, r2)) {
return m.mk_bool_val(r1 <= r2);
if (seq.unicode()) {
expr* es[2] = { ch1, ch2 };
return m.mk_app(m_fid, OP_CHAR_LE, 2, es);
}
else {
rational r1, r2;
if (bv().is_numeral(ch1, r1) && bv().is_numeral(ch2, r2)) {
return m.mk_bool_val(r1 <= r2);
}
return bv().mk_ule(ch1, ch2);
}
return bv().mk_ule(ch1, ch2);
#endif
}
app* seq_util::mk_lt(expr* ch1, expr* ch2) const {

23
src/ast/seq_decl_plugin.h
View file

@ -27,14 +27,11 @@ Revision History:
#include <string>
#include "util/lbool.h"
#define Z3_USE_UNICODE 0
enum seq_sort_kind {
SEQ_SORT,
RE_SORT,
#if Z3_USE_UNICODE
_CHAR_SORT, // internal only
#endif
_STRING_SORT,
_REGLAN_SORT
};
@ -90,10 +87,8 @@ enum seq_op_kind {
OP_STRING_TO_CODE,
OP_STRING_FROM_CODE,
#if Z3_USE_UNICODE
OP_CHAR_CONST, // constant character
OP_CHAR_LE, // Unicode comparison
#endif
// internal only operators. Converted to SEQ variants.
_OP_STRING_FROM_CHAR,
_OP_STRING_STRREPL,
@ -120,13 +115,15 @@ class zstring {
private:
buffer<unsigned> m_buffer;
bool well_formed() const;
bool uses_unicode() const;
bool is_escape_char(char const *& s, unsigned& result);
public:
static unsigned max_char() { return 196607; }
static unsigned num_bits() { return 16; }
zstring() {}
zstring(char const* s);
zstring(const std::string &str) : zstring(str.c_str()) {}
zstring(unsigned sz, unsigned const* s) { m_buffer.append(sz, s); SASSERT(well_formed()); }
zstring(unsigned num_bits, bool const* ch);
zstring(unsigned ch);
zstring replace(zstring const& src, zstring const& dst) const;
zstring reverse() const;
@ -174,6 +171,7 @@ class seq_decl_plugin : public decl_plugin {
sort* m_reglan;
bool m_has_re;
bool m_has_seq;
bool m_unicode { false };
void match(psig& sig, unsigned dsz, sort* const* dom, sort* range, sort_ref& rng);
@ -202,6 +200,8 @@ public:
~seq_decl_plugin() override {}
void finalize() override;
bool unicode() const { return m_unicode; }
decl_plugin * mk_fresh() override { return alloc(seq_decl_plugin); }
sort * mk_sort(decl_kind k, unsigned num_parameters, parameter const * parameters) override;
@ -260,14 +260,12 @@ public:
bool is_re(expr* e, sort*& seq) const { return is_re(m.get_sort(e), seq); }
bool is_char(expr* e) const { return is_char(m.get_sort(e)); }
bool is_const_char(expr* e, unsigned& c) const;
#if Z3_USE_UNICODE
bool is_char_le(expr const* e) const { return is_app_of(e, m_fid, OP_CHAR_LE); }
#else
bool is_char_le(expr const* e) const { return bv().is_bv_ule(e) && is_char(to_app(e)->get_arg(0)); }
#endif
bool is_const_char(expr* e) const { unsigned c; return is_const_char(e, c); }
bool is_char_le(expr const* e) const;
app* mk_char_bit(expr* e, unsigned i);
app* mk_char(unsigned ch) const;
app* mk_le(expr* ch1, expr* ch2) const;
app* mk_lt(expr* ch1, expr* ch2) const;
app* mk_lt(expr* ch1, expr* ch2) const;
app* mk_skolem(symbol const& name, unsigned n, expr* const* args, sort* range);
bool is_skolem(expr const* e) const { return is_app_of(e, m_fid, _OP_SEQ_SKOLEM); }
@ -317,6 +315,7 @@ public:
app* mk_replace(expr* a, expr* b, expr* c) const { expr* es[3] = { a, b, c}; return m.mk_app(m_fid, OP_SEQ_REPLACE, 3, es); }
app* mk_unit(expr* u) const { return m.mk_app(m_fid, OP_SEQ_UNIT, 1, &u); }
app* mk_char(zstring const& s, unsigned idx) const;
app* mk_char_bit(expr* e, unsigned i);
app* mk_itos(expr* i) const { return m.mk_app(m_fid, OP_STRING_ITOS, 1, &i); }
app* mk_stoi(expr* s) const { return m.mk_app(m_fid, OP_STRING_STOI, 1, &s); }
app* mk_is_empty(expr* s) const;

5
src/params/context_params.cpp
View file

@ -114,6 +114,9 @@ void context_params::set(char const * param, char const * value) {
else if (p == "smtlib2_compliant") {
set_bool(m_smtlib2_compliant, param, value);
}
else if (p == "unicode") {
set_bool(m_unicode, param, value);
}
else {
param_descrs d;
collect_param_descrs(d);
@ -145,6 +148,7 @@ void context_params::updt_params(params_ref const & p) {
m_debug_ref_count = p.get_bool("debug_ref_count", m_debug_ref_count);
m_smtlib2_compliant = p.get_bool("smtlib2_compliant", m_smtlib2_compliant);
m_statistics = p.get_bool("stats", m_statistics);
m_unicode = p.get_bool("unicode", m_unicode);
}
void context_params::collect_param_descrs(param_descrs & d) {
@ -161,6 +165,7 @@ void context_params::collect_param_descrs(param_descrs & d) {
d.insert("debug_ref_count", CPK_BOOL, "debug support for AST reference counting", "false");
d.insert("smtlib2_compliant", CPK_BOOL, "enable/disable SMT-LIB 2.0 compliance", "false");
d.insert("stats", CPK_BOOL, "enable/disable statistics", "false");
d.insert("unicode", CPK_BOOL, "use unicode strings instead of ASCII strings");
// statistics are hidden as they are controlled by the /st option.
collect_solver_param_descrs(d);
}

1
src/params/context_params.h
View file

@ -44,6 +44,7 @@ public:
bool m_smtlib2_compliant { false }; // it must be here because it enable/disable the use of coercions in the ast_manager.
unsigned m_timeout { UINT_MAX } ;
bool m_statistics { false };
bool m_unicode { false };
unsigned rlimit() const { return m_rlimit; }
context_params();

1
src/smt/params/smt_params_helper.pyg
View file

@ -104,7 +104,6 @@ def_module_params(module_name='smt',
('core.validate', BOOL, False, '[internal] validate unsat core produced by SMT context. This option is intended for debugging'),
('seq.split_w_len', BOOL, True, 'enable splitting guided by length constraints'),
('seq.validate', BOOL, False, 'enable self-validation of theory axioms created by seq theory'),
('seq.use_unicode', BOOL, False, 'dev flag (not for users) enable unicode semantics'),
('str.strong_arrangements', BOOL, True, 'assert equivalences instead of implications when generating string arrangement axioms'),
('str.aggressive_length_testing', BOOL, False, 'prioritize testing concrete length values over generating more options'),
('str.aggressive_value_testing', BOOL, False, 'prioritize testing concrete string constant values over generating more options'),

1
src/smt/params/theory_seq_params.cpp
View file

@ -21,5 +21,4 @@ void theory_seq_params::updt_params(params_ref const & _p) {
smt_params_helper p(_p);
m_split_w_len = p.seq_split_w_len();
m_seq_validate = p.seq_validate();
m_seq_use_unicode = p.seq_use_unicode();
}

4
src/smt/params/theory_seq_params.h
View file

@ -24,13 +24,11 @@ struct theory_seq_params {
*/
bool m_split_w_len;
bool m_seq_validate;
bool m_seq_use_unicode;
theory_seq_params(params_ref const & p = params_ref()):
m_split_w_len(false),
m_seq_validate(false),
m_seq_use_unicode(false)
m_seq_validate(false)
{
updt_params(p);
}

350
src/smt/seq_unicode.cpp
View file

@ -17,7 +17,6 @@ Author:
#include "smt/seq_unicode.h"
#include "smt/smt_context.h"
#include "smt/smt_arith_value.h"
#include "util/trail.h"
namespace smt {
@ -26,148 +25,261 @@ namespace smt {
th(th),
m(th.get_manager()),
seq(m),
m_qhead(0),
m_var_value_hash(*this),
m_var_value_eq(*this),
m_var_value_table(DEFAULT_HASHTABLE_INITIAL_CAPACITY, m_var_value_hash, m_var_value_eq)
{}
// <= atomic constraints on characters
void seq_unicode::assign_le(theory_var v1, theory_var v2, literal lit) {
dl.init_var(v1);
dl.init_var(v2);
ctx().push_trail(push_back_vector<context, svector<theory_var>>(m_asserted_edges));
m_asserted_edges.push_back(dl.add_edge(v1, v2, s_integer(0), lit));
bv(m),
m_bb(m, ctx().get_fparams())
{
m_enabled = gparams::get_value("unicode") == "true";
}
// < atomic constraint on characters
void seq_unicode::assign_lt(theory_var v1, theory_var v2, literal lit) {
dl.init_var(v1);
dl.init_var(v2);
ctx().push_trail(push_back_vector<context, svector<theory_var>>(m_asserted_edges));
m_asserted_edges.push_back(dl.add_edge(v1, v2, s_integer(1), lit));
struct seq_unicode::reset_bits : public trail<context> {
seq_unicode& s;
unsigned idx;
reset_bits(seq_unicode& s, unsigned idx):
s(s),
idx(idx)
{}
void undo(context& ctx) override {
s.m_bits[idx].reset();
s.m_ebits[idx].reset();
}
};
bool seq_unicode::has_bits(theory_var v) const {
return (m_bits.size() > (unsigned)v) && !m_bits[v].empty();
}
literal seq_unicode::mk_literal(expr* e) {
expr_ref _e(e, m);
th.ensure_enode(e);
return ctx().get_literal(e);
void seq_unicode::init_bits(theory_var v) {
if (has_bits(v))
return;
m_bits.reserve(v + 1);
auto& bits = m_bits[v];
expr* e = th.get_expr(v);
while ((unsigned) v >= m_ebits.size())
m_ebits.push_back(expr_ref_vector(m));
ctx().push_trail(reset_bits(*this, v));
auto& ebits = m_ebits[v];
SASSERT(ebits.empty());
for (unsigned i = 0; i < zstring::num_bits(); ++i)
ebits.push_back(seq.mk_char_bit(e, i));
ctx().internalize(ebits.c_ptr(), ebits.size(), true);
for (expr* arg : ebits)
bits.push_back(literal(ctx().get_bool_var(arg)));
}
void seq_unicode::adapt_eq(theory_var v1, theory_var v2) {
expr* e1 = th.get_expr(v1);
expr* e2 = th.get_expr(v2);
literal eq = th.mk_eq(e1, e2, false);
literal le = mk_literal(seq.mk_le(e1, e2));
literal ge = mk_literal(seq.mk_le(e2, e1));
add_axiom(~eq, le);
add_axiom(~eq, ge);
add_axiom(le, ge, eq);
void seq_unicode::internalize_le(literal lit, app* term) {
expr* x = nullptr, *y = nullptr;
VERIFY(seq.is_char_le(term, x, y));
theory_var v1 = ctx().get_enode(x)->get_th_var(th.get_id());
theory_var v2 = ctx().get_enode(y)->get_th_var(th.get_id());
auto const& b1 = get_ebits(v1);
auto const& b2 = get_ebits(v2);
expr_ref e(m);
m_bb.mk_ule(b1.size(), b1.c_ptr(), b2.c_ptr(), e);
literal le = th.mk_literal(e);
ctx().mk_th_axiom(th.get_id(), ~lit, le);
ctx().mk_th_axiom(th.get_id(), lit, ~le);
}
literal_vector const& seq_unicode::get_bits(theory_var v) {
init_bits(v);
return m_bits[v];
}
expr_ref_vector const& seq_unicode::get_ebits(theory_var v) {
init_bits(v);
return m_ebits[v];
}
// = on characters
void seq_unicode::new_eq_eh(theory_var v1, theory_var v2) {
adapt_eq(v1, v2);
void seq_unicode::new_eq_eh(theory_var v, theory_var w) {
if (has_bits(v) && has_bits(w)) {
auto& a = get_bits(v);
auto& b = get_bits(w);
unsigned i = a.size();
literal _eq = null_literal;
auto eq = [&]() {
if (_eq == null_literal)
_eq = th.mk_eq(th.get_expr(v), th.get_expr(w), false);
return _eq;
};
for (; i-- > 0; ) {
lbool v1 = ctx().get_assignment(a[i]);
lbool v2 = ctx().get_assignment(b[i]);
if (v1 != l_undef && v2 != l_undef && v1 != v2) {
enforce_ackerman(v, w);
return;
}
if (v1 == l_true)
ctx().mk_th_axiom(th.get_id(), ~eq(), ~a[i], b[i]);
if (v1 == l_false)
ctx().mk_th_axiom(th.get_id(), ~eq(), a[i], ~b[i]);
if (v2 == l_true)
ctx().mk_th_axiom(th.get_id(), ~eq(), a[i], ~b[i]);
if (v2 == l_false)
ctx().mk_th_axiom(th.get_id(), ~eq(), ~a[i], b[i]);
}
}
}
// != on characters
void seq_unicode::new_diseq_eh(theory_var v1, theory_var v2) {
adapt_eq(v1, v2);
void seq_unicode::new_diseq_eh(theory_var v, theory_var w) {
if (has_bits(v) && has_bits(w)) {
auto& a = get_bits(v);
auto& b = get_bits(w);
for (unsigned i = a.size(); i-- > 0; ) {
lbool v1 = ctx().get_assignment(a[i]);
lbool v2 = ctx().get_assignment(b[i]);
if (v1 == l_undef || v2 == l_undef || v1 != v2)
return;
}
enforce_ackerman(v, w);
}
}
bool seq_unicode::final_check() {
// ensure all variables are above 0 and less than zstring::max_char()
bool added_constraint = false;
// TBD: shift assignments on variables that are not lower-bounded, so that they are "nice" (have values 'a', 'b', ...)
// TBD: set "zero" to a zero value.
// TBD: ensure that unicode constants have the right values
arith_util a(m);
arith_value avalue(m);
avalue.init(&ctx());
for (unsigned v = 0; !ctx().inconsistent() && v < th.get_num_vars(); ++v) {
if (!seq.is_char(th.get_expr(v)))
continue;
dl.init_var(v);
auto val = dl.get_assignment(v).get_int();
if (val > static_cast<int>(zstring::max_char())) {
expr_ref ch(seq.str.mk_char(zstring::max_char()), m);
enode* n = th.ensure_enode(ch);
theory_var v_max = n->get_th_var(th.get_id());
assign_le(v, v_max, null_literal);
added_constraint = true;
continue;
}
if (val < 0) {
expr_ref ch(seq.str.mk_char(0), m);
enode* n = th.ensure_enode(ch);
theory_var v_min = n->get_th_var(th.get_id());
assign_le(v_min, v, null_literal);
dl.init_var(v_min);
dl.set_to_zero(v_min);
added_constraint = true;
continue;
}
// ensure str.to_code(unit(v)) = val
expr_ref ch(m);
if (false) {
/// m_rewrite.coalesce_chars();
ch = seq.str.mk_string(zstring(val));
}
else {
ch = seq.str.mk_unit(seq.str.mk_char(val));
}
expr_ref code(seq.str.mk_to_code(ch), m);
rational val2;
if (avalue.get_value(code, val2) && val2 == rational(val))
continue;
add_axiom(th.mk_eq(code, a.mk_int(val), false));
added_constraint = true;
void seq_unicode::new_const_char(theory_var v, unsigned c) {
auto& bits = get_bits(v);
for (auto b : bits) {
bool bit = (0 != (c & 1));
ctx().assign(bit ? b : ~b, nullptr);
c >>= 1;
}
if (added_constraint)
return false;
// ensure equalities over shared symbols
if (th.assume_eqs(m_var_value_table))
}
/**
* 1. Extract values of roots.
* Check that values of roots are unique.
* Check that values assigned to non-roots align with root values.
* Enforce that values of roots are within max_char.
* 2. Assign values to other roots that haven't been assigned.
* 3. Assign values to non-roots using values of roots.
*/
bool seq_unicode::final_check() {
m_var2value.reset();
m_var2value.resize(th.get_num_vars(), 0);
m_value2var.reset();
// extract the initial set of constants.
uint_set values;
unsigned c = 0, d = 0;
bool requires_fix = false;
for (unsigned v = th.get_num_vars(); v-- > 0; ) {
expr* e = th.get_expr(v);
if (seq.is_char(e) && th.get_enode(v)->is_root() && get_value(v, c)) {
if (c >= zstring::max_char()) {
enforce_value_bound(v);
requires_fix = true;
continue;
}
values.insert(c);
m_var2value[v] = c;
m_value2var.reserve(c + 1, null_theory_var);
theory_var w = m_value2var[c];
if (w != null_theory_var && th.get_enode(v)->get_root() != th.get_enode(w)->get_root()) {
enforce_ackerman(v, w);
requires_fix = true;
}
else {
m_value2var[c] = v;
}
for (enode* n : *th.get_enode(v)) {
theory_var w = n->get_th_var(th.get_id());
if (v != w && get_value(w, d) && d != c) {
enforce_ackerman(v, w);
requires_fix = true;
break;
}
}
}
}
if (requires_fix)
return false;
// assign values to roots
c = 'a';
for (unsigned v = th.get_num_vars(); v-- > 0; ) {
expr* e = th.get_expr(v);
if (!seq.is_char(e) || !th.get_enode(v)->is_root() || get_value(v, d))
continue;
d = c;
while (values.contains(c)) {
c = (c + 1) % zstring::max_char();
if (d == c) {
enforce_bits();
return false;
}
}
m_var2value[v] = c;
values.insert(c);
}
for (unsigned v = th.get_num_vars(); v-- > 0; ) {
expr* e = th.get_expr(v);
if (seq.is_char(e) && !th.get_enode(v)->is_root() && !get_value(v, d)) {
theory_var w = th.get_enode(v)->get_root()->get_th_var(th.get_id());
SASSERT(w != v && w != null_theory_var);
m_var2value[v] = m_var2value[w];
}
}
return true;
}
void seq_unicode::propagate() {
return;
ctx().push_trail(value_trail<smt::context, unsigned>(m_qhead));
for (; m_qhead < m_asserted_edges.size() && !ctx().inconsistent(); ++m_qhead) {
propagate(m_asserted_edges[m_qhead]);
void seq_unicode::enforce_bits() {
TRACE("seq", tout << "enforce bits\n";);
for (unsigned v = th.get_num_vars(); v-- > 0; ) {
expr* e = th.get_expr(v);
if (seq.is_char(e) && th.get_enode(v)->is_root() && !has_bits(v))
init_bits(v);
}
}
void seq_unicode::enforce_value_bound(theory_var v) {
TRACE("seq", tout << "enforce bound " << v << "\n";);
enode* n = th.ensure_enode(seq.mk_char(zstring::max_char()));
theory_var w = n->get_th_var(th.get_id());
SASSERT(has_bits(w));
auto const& mbits = get_ebits(w);
auto const& bits = get_ebits(v);
expr_ref le(m);
m_bb.mk_ule(bits.size(), bits.c_ptr(), mbits.c_ptr(), le);
ctx().assign(th.mk_literal(le), nullptr);
}
void seq_unicode::enforce_ackerman(theory_var v, theory_var w) {
TRACE("seq", tout << "enforce ackerman " << v << " " << w << "\n";);
literal eq = th.mk_eq(th.get_expr(v), th.get_expr(w), false);
literal_vector lits;
auto& a = get_ebits(v);
auto& b = get_ebits(w);
for (unsigned i = a.size(); i-- > 0; ) {
literal beq = th.mk_eq(a[i], b[i], false);
lits.push_back(~beq);
// eq => a = b
ctx().mk_th_axiom(th.get_id(), ~eq, beq);
}
// a = b => eq
lits.push_back(eq);
ctx().mk_th_axiom(th.get_id(), lits.size(), lits.c_ptr());
}
void seq_unicode::propagate(edge_id edge) {
return;
if (dl.enable_edge(edge))
return;
dl.traverse_neg_cycle2(false, m_nc_functor);
literal_vector const & lits = m_nc_functor.get_lits();
vector<parameter> params;
if (m.proofs_enabled()) {
params.push_back(parameter(symbol("farkas")));
for (unsigned i = 0; i <= lits.size(); ++i) {
params.push_back(parameter(rational(1)));
}
}
ctx().set_conflict(
ctx().mk_justification(
ext_theory_conflict_justification(
th.get_id(), ctx().get_region(),
lits.size(), lits.c_ptr(),
0, nullptr,
params.size(), params.c_ptr())));;
}
unsigned seq_unicode::get_value(theory_var v) {
dl.init_var(v);
auto val = dl.get_assignment(v);
return val.get_int();
return m_var2value[v];
}
bool seq_unicode::get_value(theory_var v, unsigned& c) {
if (!has_bits(v))
return false;
auto const & b = get_bits(v);
c = 0;
unsigned p = 1;
for (literal lit : b) {
if (ctx().get_assignment(lit) == l_true)
c += p;
p *= 2;
}
return true;
}
}

82
src/smt/seq_unicode.h
View file

@ -16,83 +16,59 @@ Author:
--*/
#pragma once
#include "util/s_integer.h"
#include "ast/seq_decl_plugin.h"
#include "ast/bv_decl_plugin.h"
#include "ast/rewriter/bit_blaster/bit_blaster.h"
#include "smt/smt_theory.h"
#include "smt/diff_logic.h"
namespace smt {
class seq_unicode {
struct ext {
static const bool m_int_theory = true;
typedef s_integer numeral;
typedef s_integer fin_numeral;
numeral m_epsilon;
typedef literal explanation;
ext(): m_epsilon(1) {}
};
class nc_functor {
literal_vector m_literals;
public:
nc_functor() {}
void operator()(literal const& l) {
if (l != null_literal) m_literals.push_back(l);
}
literal_vector const& get_lits() const { return m_literals; }
void new_edge(dl_var s, dl_var d, unsigned num_edges, edge_id const* edges) {}
};
struct var_value_hash {
seq_unicode & m_th;
var_value_hash(seq_unicode & th):m_th(th) {}
unsigned operator()(theory_var v) const { return m_th.get_value(v); }
};
struct var_value_eq {
seq_unicode & m_th;
var_value_eq(seq_unicode & th):m_th(th) {}
bool operator()(theory_var v1, theory_var v2) const {
return m_th.get_value(v1) == m_th.get_value(v2);
}
};
typedef int_hashtable<var_value_hash, var_value_eq> var_value_table;
theory& th;
ast_manager& m;
seq_util seq;
dl_graph<ext> dl;
unsigned m_qhead;
svector<edge_id> m_asserted_edges;
nc_functor m_nc_functor;
var_value_hash m_var_value_hash;
var_value_eq m_var_value_eq;
var_value_table m_var_value_table;
std::function<void(literal, literal, literal)> m_add_axiom;
bv_util bv;
vector<literal_vector> m_bits;
vector<expr_ref_vector> m_ebits;
unsigned_vector m_var2value;
svector<theory_var> m_value2var;
bool m_enabled { false };
bit_blaster m_bb;
struct reset_bits;
context& ctx() const { return th.get_context(); }
void propagate(edge_id edge);
literal_vector const& get_bits(theory_var v);
void add_axiom(literal a, literal b = null_literal, literal c = null_literal) {
m_add_axiom(a, b, c);
}
expr_ref_vector const& get_ebits(theory_var v);
void adapt_eq(theory_var v1, theory_var v2);
bool has_bits(theory_var v) const;
literal mk_literal(expr* e);
void init_bits(theory_var v);
bool get_value(theory_var v, unsigned& c);
void enforce_ackerman(theory_var v, theory_var w);
void enforce_value_bound(theory_var v);
void enforce_bits();
public:
seq_unicode(theory& th);
bool enabled() const { return m_enabled; }
// <= atomic constraints on characters
void assign_le(theory_var v1, theory_var v2, literal lit);
// < atomic constraint on characters
void assign_lt(theory_var v1, theory_var v2, literal lit);
void new_const_char(theory_var v, unsigned c);
// = on characters
void new_eq_eh(theory_var v1, theory_var v2);
@ -105,9 +81,7 @@ namespace smt {
unsigned get_value(theory_var v);
void propagate();
bool can_propagate() const { return m_qhead < m_asserted_edges.size(); }
void internalize_le(literal lit, app* term);
};

38
src/smt/theory_seq.cpp
View file

@ -354,7 +354,7 @@ final_check_status theory_seq::final_check_eh() {
TRACEFIN("zero_length");
return FC_CONTINUE;
}
if (ctx.get_fparams().m_seq_use_unicode && !m_unicode.final_check()) {
if (m_unicode.enabled() && !m_unicode.final_check()) {
return FC_CONTINUE;
}
if (get_fparams().m_split_w_len && len_based_split()) {
@ -737,7 +737,6 @@ void theory_seq::propagate_lit(dependency* dep, unsigned n, literal const* _lits
set_conflict(dep, lits);
return;
}
ctx.mark_as_relevant(lit);
enode_pair_vector eqs;
linearize(dep, eqs, lits);
@ -1519,6 +1518,11 @@ bool theory_seq::internalize_term(app* term) {
bool_var bv = ctx.mk_bool_var(term);
ctx.set_var_theory(bv, get_id());
ctx.mark_as_relevant(bv);
if (m_util.is_char_le(term) && m_unicode.enabled()) {
mk_var(ensure_enode(term->get_arg(0)));
mk_var(ensure_enode(term->get_arg(1)));
m_unicode.internalize_le(literal(bv, false), term);
}
}
enode* e = nullptr;
@ -1528,10 +1532,15 @@ bool theory_seq::internalize_term(app* term) {
else {
e = ctx.mk_enode(term, false, m.is_bool(term), true);
}
mk_var(e);
theory_var v = mk_var(e);
if (!ctx.relevancy()) {
relevant_eh(term);
}
unsigned c = 0;
if (m_unicode.enabled() && m_util.is_const_char(term, c))
m_unicode.new_const_char(v, c);
return true;
}
@ -2015,6 +2024,10 @@ model_value_proc * theory_seq::mk_value(enode * n, model_generator & mg) {
m_concat.shrink(start);
return sv;
}
else if (m_unicode.enabled() && m_util.is_char(e)) {
unsigned ch = m_unicode.get_value(n->get_th_var(get_id()));
return alloc(expr_wrapper_proc, m_util.str.mk_char(ch));
}
else {
return alloc(expr_wrapper_proc, mk_value(e));
}
@ -2319,7 +2332,7 @@ void theory_seq::validate_fmls(enode_pair_vector const& eqs, literal_vector cons
theory_var theory_seq::mk_var(enode* n) {
expr* o = n->get_owner();
if (!m_util.is_seq(o) && !m_util.is_re(o))
if (!m_util.is_seq(o) && !m_util.is_re(o) && (!m_unicode.enabled() || !m_util.is_char(o)))
return null_theory_var;
if (is_attached_to_var(n))
@ -2333,7 +2346,7 @@ theory_var theory_seq::mk_var(enode* n) {
}
bool theory_seq::can_propagate() {
return m_axioms_head < m_axioms.size() || !m_replay.empty() || m_new_solution || m_unicode.can_propagate() || m_regex.can_propagate();
return m_axioms_head < m_axioms.size() || !m_replay.empty() || m_new_solution || m_regex.can_propagate();
}
bool theory_seq::canonize(expr* e, dependency*& eqs, expr_ref& result) {
@ -2525,8 +2538,6 @@ void theory_seq::add_dependency(dependency*& dep, enode* a, enode* b) {
void theory_seq::propagate() {
if (ctx.get_fparams().m_seq_use_unicode)
m_unicode.propagate();
if (m_regex.can_propagate())
m_regex.propagate();
while (m_axioms_head < m_axioms.size() && !ctx.inconsistent()) {
@ -2980,13 +2991,8 @@ void theory_seq::assign_eh(bool_var v, bool is_true) {
else if (m_util.str.is_nth_i(e) || m_util.str.is_nth_u(e)) {
// no-op
}
else if (ctx.get_fparams().m_seq_use_unicode && m_util.is_char_le(e, e1, e2)) {
theory_var v1 = get_th_var(ctx.get_enode(e1));
theory_var v2 = get_th_var(ctx.get_enode(e2));
if (is_true)
m_unicode.assign_le(v1, v2, lit);
else
m_unicode.assign_lt(v2, v1, lit);
else if (m_unicode.enabled() && m_util.is_char_le(e)) {
// no-op
}
else if (m_util.is_skolem(e)) {
@ -3006,7 +3012,7 @@ void theory_seq::new_eq_eh(theory_var v1, theory_var v2) {
enode* n2 = get_enode(v2);
expr* o1 = n1->get_owner();
expr* o2 = n2->get_owner();
if (ctx.get_fparams().m_seq_use_unicode && m_util.is_char(o1)) {
if (m_unicode.enabled() && m_util.is_char(o1)) {
m_unicode.new_eq_eh(v1, v2);
return;
}
@ -3057,7 +3063,7 @@ void theory_seq::new_diseq_eh(theory_var v1, theory_var v2) {
m_regex.propagate_ne(e1, e2);
return;
}
if (ctx.get_fparams().m_seq_use_unicode && m_util.is_char(n1->get_owner())) {
if (m_unicode.enabled() && m_util.is_char(n1->get_owner())) {
m_unicode.new_diseq_eh(v1, v2);
return;
}