lean2/src/kernel/level.cpp
Leonardo de Moura 31abc00db8 chore(*): add LCOV_EXCL_LINE to lean_unreachable statements
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
2013-11-11 09:19:38 -08:00

261 lines
9.6 KiB
C++

/*
Copyright (c) 2013 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Author: Leonardo de Moura
*/
#include <algorithm>
#include "util/safe_arith.h"
#include "util/buffer.h"
#include "util/rc.h"
#include "util/debug.h"
#include "util/hash.h"
#include "kernel/level.h"
namespace lean {
/** \brief Base class for representing universe level cells. */
struct level_cell {
void dealloc();
MK_LEAN_RC()
level_kind m_kind;
level_cell(level_kind k):m_rc(1), m_kind(k) {}
};
/** \brief Cell for universe variables. */
struct level_uvar : public level_cell {
name m_name;
level_uvar(name const & n):level_cell(level_kind::UVar), m_name(n) {}
};
/** \brief Cell for representing the universe <tt>l + k</tt>, where \c l is a level and \c k a unsigned integer. */
struct level_lift : public level_cell {
level m_l;
unsigned m_k;
level_lift(level const & l, unsigned k):level_cell(level_kind::Lift), m_l(l), m_k(k) {}
};
/** \brief Cell for representing the universe <tt>max l_1 ... l_n</tt>, where <tt>n == m_size</tt>. */
struct level_max : public level_cell {
unsigned m_size;
level m_levels[0];
level_max(unsigned sz, level const * ls):level_cell(level_kind::Max), m_size(sz) {
for (unsigned i = 0; i < m_size; i++)
new (m_levels + i) level(ls[i]);
}
~level_max() {
for (unsigned i = 0; i < m_size; i++)
(m_levels+i)->~level();
}
level const * begin_levels() const { return m_levels; }
level const * end_levels() const { return m_levels + m_size; }
};
level_uvar * to_uvar(level_cell * c) { return static_cast<level_uvar*>(c); }
level_lift * to_lift(level_cell * c) { return static_cast<level_lift*>(c); }
level_max * to_max(level_cell * c) { return static_cast<level_max*>(c); }
void level_cell::dealloc() {
switch (m_kind) {
case level_kind::UVar: delete to_uvar(this); break;
case level_kind::Lift: delete to_lift(this); break;
case level_kind::Max: static_cast<level_max*>(this)->~level_max(); delete[] reinterpret_cast<char*>(this); break;
}
}
static name g_bot_name("bot");
level::level(): m_ptr(new level_uvar(g_bot_name)) { lean_assert_eq(uvar_name(*this), name("bot")); }
level::level(name const & n): m_ptr(new level_uvar(n)) {}
level::level(level const & l, unsigned k):m_ptr(new level_lift(l, k)) { lean_assert(is_uvar(l)); }
level::level(level_cell * ptr): m_ptr(ptr) { lean_assert(m_ptr->get_rc() == 1); }
level::level(level const & s):
m_ptr(s.m_ptr) {
if (m_ptr)
m_ptr->inc_ref();
}
level::level(level && s):
m_ptr(s.m_ptr) {
s.m_ptr = nullptr;
}
level::~level() {
if (m_ptr)
m_ptr->dec_ref();
}
level to_level(level_cell * c) { return level(c); }
level_cell * to_cell(level const & l) { return l.m_ptr; }
level_max * to_max(level const & l) { return to_max(to_cell(l)); }
unsigned level::hash() const {
switch (m_ptr->m_kind) {
case level_kind::UVar: return to_uvar(m_ptr)->m_name.hash();
case level_kind::Lift: return ::lean::hash(to_lift(m_ptr)->m_l.hash(), to_lift(m_ptr)->m_k);
case level_kind::Max: return ::lean::hash(to_max(m_ptr)->m_size, [&](unsigned i) { return to_max(m_ptr)->m_levels[i].hash(); });
}
return 0;
}
bool level::is_bottom() const {
return is_uvar(*this) && uvar_name(*this) == g_bot_name;
}
level max_core(unsigned sz, level const * ls) {
char * mem = new char[sizeof(level_max) + sz*sizeof(level)];
return to_level(new (mem) level_max(sz, ls));
}
level const & _lift_of(level const & l) { return is_lift(l) ? lift_of(l) : l; }
unsigned _lift_offset(level const & l) { return is_lift(l) ? lift_offset(l) : 0; }
void push_back(buffer<level> & ls, level const & l) {
for (unsigned i = 0; i < ls.size(); i++) {
if (_lift_of(ls[i]) == _lift_of(l)) {
if (_lift_offset(ls[i]) < _lift_offset(l))
ls[i] = l;
return;
}
}
ls.push_back(l);
}
level max_core(unsigned sz1, level const * ls1, unsigned sz2, level const * ls2) {
buffer<level> new_lvls;
std::for_each(ls1, ls1 + sz1, [&](level const & l) { push_back(new_lvls, l); });
std::for_each(ls2, ls2 + sz2, [&](level const & l) { push_back(new_lvls, l); });
if (new_lvls.size() == 1)
return new_lvls[0];
else
return max_core(new_lvls.size(), new_lvls.data());
}
level max_core(level const & l1, level const & l2) { return max_core(1, &l1, 1, &l2); }
level max_core(level const & l1, level_max * l2) { return max_core(1, &l1, l2->m_size, l2->m_levels); }
level max_core(level_max * l1, level const & l2) { return max_core(l1->m_size, l1->m_levels, 1, &l2); }
level max_core(level_max * l1, level_max * l2) { return max_core(l1->m_size, l1->m_levels, l2->m_size, l2->m_levels); }
level max(level const & l1, level const & l2) {
if (is_max(l1)) {
if (is_max(l2))
return max_core(to_max(l1), to_max(l2));
else
return max_core(to_max(l1), l2);
} else {
if (is_max(l2))
return max_core(l1, to_max(l2));
else
return max_core(l1, l2);
}
}
level operator+(level const & l, unsigned k) {
switch (kind(l)) {
case level_kind::UVar: return level(l, k);
case level_kind::Lift: return level(lift_of(l), safe_add(lift_offset(l), k));
case level_kind::Max: {
buffer<level> new_lvls;
for (unsigned i = 0; i < max_size(l); i++)
new_lvls.push_back(max_level(l, i) + k);
return max_core(new_lvls.size(), new_lvls.data());
}}
lean_unreachable(); // LCOV_EXCL_LINE
}
level_kind kind (level const & l) { lean_assert(l.m_ptr); return l.m_ptr->m_kind; }
name const & uvar_name (level const & l) { lean_assert(is_uvar(l)); return static_cast<level_uvar*>(l.m_ptr)->m_name; }
level const & lift_of (level const & l) { lean_assert(is_lift(l)); return static_cast<level_lift*>(l.m_ptr)->m_l; }
unsigned lift_offset(level const & l) { lean_assert(is_lift(l)); return static_cast<level_lift*>(l.m_ptr)->m_k; }
unsigned max_size (level const & l) { lean_assert(is_max(l)); return static_cast<level_max*>(l.m_ptr)->m_size; }
level const & max_level (level const & l, unsigned i) { lean_assert(is_max(l)); return static_cast<level_max*>(l.m_ptr)->m_levels[i]; }
level & level::operator=(level const & l) { LEAN_COPY_REF(level, l); }
level & level::operator=(level&& l) { LEAN_MOVE_REF(level, l); }
bool operator==(level const & l1, level const & l2) {
if (kind(l1) != kind(l2)) return false;
switch (kind(l1)) {
case level_kind::UVar: return uvar_name(l1) == uvar_name(l2);
case level_kind::Lift: return lift_of(l1) == lift_of(l2) && lift_offset(l1) == lift_offset(l2);
case level_kind::Max:
if (max_size(l1) == max_size(l2)) {
for (unsigned i = 0; i < max_size(l1); i++)
if (max_level(l1, i) != max_level(l2, i))
return false;
return true;
} else {
return false;
}
}
lean_unreachable(); // LCOV_EXCL_LINE
}
bool operator<(level const & l1, level const & l2) {
if (kind(l1) != kind(l2)) return kind(l1) < kind(l2);
switch (kind(l1)) {
case level_kind::UVar: return uvar_name(l1) < uvar_name(l2);
case level_kind::Lift:
if (lift_of(l1) != lift_of(l2))
return lift_of(l1) < lift_of(l2);
else
return lift_offset(l1) < lift_offset(l2);
case level_kind::Max:
if (max_size(l1) != max_size(l2))
return max_size(l1) < max_size(l2);
for (unsigned i = 0; i < max_size(l1); i++)
if (max_level(l1, i) != max_level(l2, i))
return max_level(l1, i) < max_level(l2, i);
return false;
}
lean_unreachable(); // LCOV_EXCL_LINE
}
std::ostream & operator<<(std::ostream & out, level const & l) {
switch (kind(l)) {
case level_kind::UVar: out << uvar_name(l); return out;
case level_kind::Lift:
if (lift_of(l).is_bottom())
out << lift_offset(l);
else
out << lift_of(l) << "+" << lift_offset(l);
return out;
case level_kind::Max:
out << "(max";
for (unsigned i = 0; i < max_size(l); i++)
out << " " << max_level(l, i);
out << ")";
return out;
}
return out;
}
format pp(level const & l, bool unicode) {
switch (kind(l)) {
case level_kind::UVar:
if (l.is_bottom())
return format(0);
else
return pp(uvar_name(l));
case level_kind::Lift:
if (lift_of(l).is_bottom())
return format(lift_offset(l));
else
return format{pp(lift_of(l), unicode), format("+"), format(lift_offset(l))};
case level_kind::Max: {
if (unicode) {
format r = pp(max_level(l, 0), unicode);
for (unsigned i = 1; i < max_size(l); i++) {
r += format{space(), format("\u2294"), line()};
r += pp(max_level(l, i), unicode);
}
return group(r);
} else {
format r = format("max");
for (unsigned i = 0; i < max_size(l); i++)
r += format{line(), pp(max_level(l, i), unicode)};
return paren(r);
}
}}
lean_unreachable(); // LCOV_EXCL_LINE
}
format pp(level const & l, options const & opts) {
return pp(l, get_pp_unicode(opts));
}
level max(std::initializer_list<level> const & l) {
if (l.size() == 1)
return *(l.begin());
return max_core(l.size(), l.begin());
}
}
void print(lean::level const & l) { std::cout << l << std::endl; }