refactor(library/type_context): move unification_hints to cache object

src/library/abstract_context_cache.cpp

@@ -109,6 +109,10 @@ bool context_cacheless::get_aux_recursor(type_context & ctx, name const & n) {
     return ::lean::is_aux_recursor(ctx.env(), n);
 }
 
+void context_cacheless::get_unification_hints(type_context & ctx, name const & f1, name const & f2, buffer<unification_hint> & hints) {
+    return ::lean::get_unification_hints(ctx.env(), f1, f2, hints);
+}
+
 void initialize_abstract_context_cache() {
     g_class_instance_max_depth     = new name{"class", "instance_max_depth"};
     register_unsigned_option(*g_class_instance_max_depth, LEAN_DEFAULT_CLASS_INSTANCE_MAX_DEPTH,

src/library/abstract_context_cache.h

@@ -12,6 +12,7 @@ Author: Leonardo de Moura
 #include "library/projection.h"
 #include "library/fun_info.h"
 #include "library/local_instances.h"
+#include "library/unification_hint.h"
 
 namespace lean {
 #define LEAN_NUM_TRANSPARENCY_MODES 5
@@ -181,6 +182,7 @@ public:
     virtual optional<declaration> get_decl(type_context &, transparency_mode, name const &) = 0;
     virtual projection_info const * get_proj_info(type_context &, name const &) = 0;
     virtual bool get_aux_recursor(type_context &, name const &) = 0;
+    virtual void get_unification_hints(type_context &, name const & f1, name const & f2, buffer<unification_hint> & hints) = 0;
 
     /* Cache support for type_context module */
 
@@ -296,6 +298,7 @@ public:
     virtual optional<declaration> get_decl(type_context &, transparency_mode, name const &) override;
     virtual projection_info const * get_proj_info(type_context &, name const &) override;
     virtual bool get_aux_recursor(type_context &, name const &) override;
+    virtual void get_unification_hints(type_context &, name const & f1, name const & f2, buffer<unification_hint> & hints) override;
 
     /* Cache support for type_context module */
 

src/library/context_cache.cpp

@@ -5,6 +5,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Author: Leonardo de Moura
 */
 #include "library/context_cache.h"
+#include "library/type_context.h"
 
 namespace lean {
 context_cache::context_cache():
@@ -43,6 +44,12 @@ bool context_cache::get_aux_recursor(type_context & ctx, name const & n) {
     return r;
 }
 
+void context_cache::get_unification_hints(type_context & ctx, name const & f1, name const & f2, buffer<unification_hint> & hints) {
+    if (!m_uhints)
+        m_uhints = ::lean::get_unification_hints(ctx.env());
+    ::lean::get_unification_hints(*m_uhints, f1, f2, hints);
+}
+
 template<typename R, typename C>
 optional<R> find_at(C const & c, expr const & e) {
     auto it = c.find(e);

src/library/context_cache.h

@@ -87,6 +87,8 @@ class context_cache : public context_cacheless {
           cache manager. */
     instance_cache                m_instance_cache;
     subsingleton_cache            m_subsingleton_cache;
+
+    optional<unification_hints>   m_uhints;
 public:
     context_cache();
     context_cache(options const & o);
@@ -100,6 +102,7 @@ public:
     virtual optional<declaration> get_decl(type_context &, transparency_mode, name const &) override;
     virtual projection_info const * get_proj_info(type_context &, name const &) override;
     virtual bool get_aux_recursor(type_context &, name const &) override;
+    virtual void get_unification_hints(type_context &, name const & f1, name const & f2, buffer<unification_hint> & hints) override;
 
     /* Cache support for type_context module */
 

src/library/persistent_context_cache.cpp

@@ -63,6 +63,10 @@ bool persistent_context_cache::get_aux_recursor(type_context & ctx, name const &
     return m_cache_ptr->get_aux_recursor(ctx, n);
 }
 
+void persistent_context_cache::get_unification_hints(type_context & ctx, name const & f1, name const & f2, buffer<unification_hint> & hints) {
+    return m_cache_ptr->get_unification_hints(ctx, f1, f2, hints);
+}
+
 optional<expr> persistent_context_cache::get_infer(expr const & e) {
     return m_cache_ptr->get_infer(e);
 }

src/library/persistent_context_cache.h

@@ -46,6 +46,7 @@ public:
     virtual optional<declaration> get_decl(type_context &, transparency_mode, name const &) override;
     virtual projection_info const * get_proj_info(type_context &, name const &) override;
     virtual bool get_aux_recursor(type_context &, name const &) override;
+    virtual void get_unification_hints(type_context &, name const & f1, name const & f2, buffer<unification_hint> & hints) override;
 
     /* Cache support for type_context module */
 

src/library/type_context.cpp

@@ -134,7 +134,6 @@ void type_context::init_core(transparency_mode m) {
         init_local_instances();
         flush_instance_cache();
     }
-    m_uhints = get_unification_hints(env());
 }
 
 type_context::type_context(environment const & env, options const & o, metavar_context const & mctx,
@@ -164,8 +163,7 @@ type_context::type_context(type_context && src):
     m_transparency_mode(src.m_transparency_mode),
     m_approximate(src.m_approximate),
     m_zeta(src.m_zeta),
-    m_smart_unfolding(src.m_smart_unfolding),
-    m_uhints(src.m_uhints) {
+    m_smart_unfolding(src.m_smart_unfolding) {
     lean_assert(!src.m_tmp_data);
     lean_assert(!src.m_used_assignment);
     lean_assert(!src.m_in_is_def_eq);
@@ -184,7 +182,6 @@ type_context::~type_context() {
 
 void type_context::set_env(environment const & env) {
     m_env    = env;
-    m_uhints = get_unification_hints(env);
 }
 
 void type_context::update_local_instances(expr const & new_local, expr const & new_type) {
@@ -3295,7 +3292,7 @@ bool type_context::try_unification_hints(expr const & e1, expr const & e2) {
     expr e2_fn = get_app_fn(e2);
     if (is_constant(e1_fn) && is_constant(e2_fn)) {
         buffer<unification_hint> hints;
-        get_unification_hints(m_uhints, const_name(e1_fn), const_name(e2_fn), hints);
+        m_cache->get_unification_hints(*this, const_name(e1_fn), const_name(e2_fn), hints);
         for (unification_hint const & hint : hints) {
             lean_trace(name({"type_context", "unification_hint"}),
                        scope_trace_env scope(env(), *this);

src/library/type_context.h

@@ -524,7 +524,6 @@ private:
        that cannot be solved precisely are ignored. This step is approximate, and it is
        useful to skip it until we have additional information. */
     bool                       m_full_postponed{true};
-    unification_hints          m_uhints;
 
     std::function<bool(name const & e)> const * m_transparency_pred{nullptr}; // NOLINT