compiler, runtime: change type hash/equal to Go funcs

    
    Change the type descriptor hash and equal functions from C code pointers
    to Go func values.  This permits them to be set to a Go function
    closure.  This is in preparation for the Go 1.5, so that we can use a
    closure for the hash/equal functions returned by the new reflect.ArrayOf
    function.
    
    Reviewed-on: https://go-review.googlesource.com/16485

From-SVN: r229541

3 files changed, 48 insertions, 13 deletions

diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE
index 6fcd185..8d3547b 100644
--- a/gcc/go/gofrontend/MERGE
+++ b/gcc/go/gofrontend/MERGE
@@ -1,4 +1,4 @@
-11e249a59e8c627fe9c2938c38e39cb1efefb1fb
+57da43e8159bfe1a31e49683c371cf36e2fb6051
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.
diff --git a/gcc/go/gofrontend/expressions.cc b/gcc/go/gofrontend/expressions.cc
index 0d25dda..c9750bd 100644
--- a/gcc/go/gofrontend/expressions.cc
+++ b/gcc/go/gofrontend/expressions.cc
@@ -1197,19 +1197,29 @@ Func_descriptor_expression::do_get_backend(Translate_context* context)
 
   Gogo* gogo = context->gogo();
   std::string var_name;
-  if (no->package() == NULL)
-    var_name = gogo->pkgpath_symbol();
+  bool is_descriptor = false;
+  if (no->is_function_declaration()
+      && !no->func_declaration_value()->asm_name().empty()
+      && Linemap::is_predeclared_location(no->location()))
+    {
+      var_name = no->func_declaration_value()->asm_name() + "_descriptor";
+      is_descriptor = true;
+    }
   else
-    var_name = no->package()->pkgpath_symbol();
-  var_name.push_back('.');
-  var_name.append(Gogo::unpack_hidden_name(no->name()));
-  var_name.append("$descriptor");
+    {
+      if (no->package() == NULL)
+	var_name = gogo->pkgpath_symbol();
+      else
+	var_name = no->package()->pkgpath_symbol();
+      var_name.push_back('.');
+      var_name.append(Gogo::unpack_hidden_name(no->name()));
+      var_name.append("$descriptor");
+    }
 
   Btype* btype = this->type()->get_backend(gogo);
 
   Bvariable* bvar;
-  if (no->package() != NULL
-      || Linemap::is_predeclared_location(no->location()))
+  if (no->package() != NULL || is_descriptor)
     bvar = context->backend()->immutable_struct_reference(var_name, btype,
 							  loc);
   else
diff --git a/gcc/go/gofrontend/types.cc b/gcc/go/gofrontend/types.cc
index dcc6bc8..5c8950a 100644
--- a/gcc/go/gofrontend/types.cc
+++ b/gcc/go/gofrontend/types.cc
@@ -1474,6 +1474,27 @@ Type::make_type_descriptor_type()
       Type* void_type = Type::make_void_type();
       Type* unsafe_pointer_type = Type::make_pointer_type(void_type);
 
+      Typed_identifier_list *params = new Typed_identifier_list();
+      params->push_back(Typed_identifier("key", unsafe_pointer_type, bloc));
+      params->push_back(Typed_identifier("key_size", uintptr_type, bloc));
+
+      Typed_identifier_list* results = new Typed_identifier_list();
+      results->push_back(Typed_identifier("", uintptr_type, bloc));
+
+      Type* hash_fntype = Type::make_function_type(NULL, params, results,
+						   bloc);
+
+      params = new Typed_identifier_list();
+      params->push_back(Typed_identifier("key1", unsafe_pointer_type, bloc));
+      params->push_back(Typed_identifier("key2", unsafe_pointer_type, bloc));
+      params->push_back(Typed_identifier("key_size", uintptr_type, bloc));
+
+      results = new Typed_identifier_list();
+      results->push_back(Typed_identifier("", Type::lookup_bool_type(), bloc));
+
+      Type* equal_fntype = Type::make_function_type(NULL, params, results,
+						    bloc);
+
       // Forward declaration for the type descriptor type.
       Named_object* named_type_descriptor_type =
 	Named_object::make_type_declaration("commonType", NULL, bloc);
@@ -1514,8 +1535,8 @@ Type::make_type_descriptor_type()
 				       "fieldAlign", uint8_type,
 				       "size", uintptr_type,
 				       "hash", uint32_type,
-				       "hashfn", uintptr_type,
-				       "equalfn", uintptr_type,
+				       "hashfn", hash_fntype,
+				       "equalfn", equal_fntype,
 				       "gc", uintptr_type,
 				       "string", pointer_string_type,
 				       "", pointer_uncommon_type,
@@ -1852,6 +1873,10 @@ Type::write_specific_type_functions(Gogo* gogo, Named_type* name,
   gogo->add_block(b, bloc);
   gogo->lower_block(equal_fn, b);
   gogo->finish_function(bloc);
+
+  // Build the function descriptors for the type descriptor to refer to.
+  hash_fn->func_value()->descriptor(gogo, hash_fn);
+  equal_fn->func_value()->descriptor(gogo, equal_fn);
 }
 
 // Write a hash function that simply calls the hash function for a
@@ -2009,8 +2034,8 @@ Type::type_descriptor_constructor(Gogo* gogo, int runtime_type_kind,
   Named_object* equal_fn;
   this->type_functions(gogo, name, hash_fntype, equal_fntype, &hash_fn,
 		       &equal_fn);
-  vals->push_back(Expression::make_func_code_reference(hash_fn, bloc));
-  vals->push_back(Expression::make_func_code_reference(equal_fn, bloc));
+  vals->push_back(Expression::make_func_reference(hash_fn, NULL, bloc));
+  vals->push_back(Expression::make_func_reference(equal_fn, NULL, bloc));
 
   ++p;
   go_assert(p->is_field_name("gc"));