From 67b68b8139ca4e45c8948642cd6678159ae51311 Mon Sep 17 00:00:00 2001 From: Ian Lance Taylor Date: Wed, 29 Apr 2015 22:14:34 +0000 Subject: [PATCH] compiler: Propagate escape info from closures to enclosed variables. If a closure escapes, the enclosed variables must escape via the closure. Reachability analysis had a bug where the enclosed variables were not considered as reachable from the closure. From-SVN: r222597 --- gcc/go/gofrontend/escape.cc | 43 +++++++++++++++++++++++++++++++------ gcc/go/gofrontend/gogo.h | 5 +++++ 2 files changed, 41 insertions(+), 7 deletions(-) diff --git a/gcc/go/gofrontend/escape.cc b/gcc/go/gofrontend/escape.cc index 7c8955bb8a5..d2e7ae12931 100644 --- a/gcc/go/gofrontend/escape.cc +++ b/gcc/go/gofrontend/escape.cc @@ -1276,8 +1276,22 @@ Gogo::analyze_reachability() Node* m = worklist.front(); worklist.pop_front(); - for (std::set::iterator n = m->edges().begin(); - n != m->edges().end(); + std::set reachable = m->edges(); + if (m->object()->is_function() + && m->object()->func_value()->needs_closure()) + { + // If a closure escapes everything it closes over also escapes. + Function* closure = m->object()->func_value(); + for (size_t i = 0; i < closure->closure_field_count(); i++) + { + Named_object* enclosed = closure->enclosing_var(i); + Node* enclosed_node = this->lookup_connection_node(enclosed); + go_assert(enclosed_node != NULL); + reachable.insert(enclosed_node); + } + } + for (std::set::iterator n = reachable.begin(); + n != reachable.end(); ++n) { // If an object can be reached from a node with ESCAPE_GLOBAL, @@ -1296,7 +1310,7 @@ Gogo::analyze_reachability() p != this->named_connection_nodes_.end(); ++p) { - if (p->second->connection_node()->escape_state() == Node::ESCAPE_ARG) + if (p->second->connection_node()->escape_state() < Node::ESCAPE_NONE) worklist.push_back(p->second); } @@ -1305,15 +1319,30 @@ Gogo::analyze_reachability() Node* m = worklist.front(); worklist.pop_front(); - for (std::set::iterator n = m->edges().begin(); - n != m->edges().end(); + std::set reachable = m->edges(); + if (m->object()->is_function() + && m->object()->func_value()->needs_closure()) + { + // If a closure escapes everything it closes over also escapes. + Function* closure = m->object()->func_value(); + for (size_t i = 0; i < closure->closure_field_count(); i++) + { + Named_object* enclosed = closure->enclosing_var(i); + Node* enclosed_node = this->lookup_connection_node(enclosed); + go_assert(enclosed_node != NULL); + reachable.insert(enclosed_node); + } + } + for (std::set::iterator n = reachable.begin(); + n != reachable.end(); ++n) { // If an object can be reached from a node with ESCAPE_ARG, // it is ESCAPE_ARG or ESCAPE_GLOBAL. - if ((*n)->connection_node()->escape_state() > Node::ESCAPE_ARG) + Node::Escapement_lattice e = m->connection_node()->escape_state(); + if ((*n)->connection_node()->escape_state() > e) { - (*n)->connection_node()->set_escape_state(Node::ESCAPE_ARG); + (*n)->connection_node()->set_escape_state(e); worklist.push_back(*n); } } diff --git a/gcc/go/gofrontend/gogo.h b/gcc/go/gofrontend/gogo.h index e30178d6c23..ffc2440f8ff 100644 --- a/gcc/go/gofrontend/gogo.h +++ b/gcc/go/gofrontend/gogo.h @@ -1042,6 +1042,11 @@ class Function this->is_unnamed_type_stub_method_ = true; } + // Return the amount of enclosed variables in this closure. + size_t + closure_field_count() const + { return this->closure_fields_.size(); } + // Add a new field to the closure variable. void add_closure_field(Named_object* var, Location loc)