This patch by Cherry Zhang changes the Go frontend to more clearly
connect the concrete type and the placeholder for circular types.
Previously, when creating the backend representation of a circular
type, we resolved the placeholder to a circular_pointer_type. The
backend didn't know what the concrete type would be. This patch
changes the frontend to resolve the placeholder to the concrete type
instead, so the backend can have better knowledge of the concrete
type. Bootstrapped and ran Go testsuite on x86_64-pc-linux-gnu.
Committed to mainline.
Ian
Index: gcc/go/gofrontend/MERGE
===================================================================
--- gcc/go/gofrontend/MERGE (revision 262658)
+++ gcc/go/gofrontend/MERGE (working copy)
@@ -1,4 +1,4 @@
-db991403fc97854201b3f40492f4f6b9d471cabc
+d6338c94e5574b63469c740159d064e89c6718bf
The first line of this file holds the git revision number of the last
merge done from the gofrontend repository.
Index: gcc/go/gofrontend/types.cc
===================================================================
--- gcc/go/gofrontend/types.cc (revision 262658)
+++ gcc/go/gofrontend/types.cc (working copy)
@@ -10786,15 +10786,10 @@ Named_type::do_get_backend(Gogo* gogo)
// Don't build a circular data structure. GENERIC can't handle
// it.
if (this->seen_in_get_backend_)
- {
- this->is_circular_ = true;
- return gogo->backend()->circular_pointer_type(bt, true);
- }
+ return gogo->backend()->circular_pointer_type(bt, true);
this->seen_in_get_backend_ = true;
bt1 = Type::get_named_base_btype(gogo, base);
this->seen_in_get_backend_ = false;
- if (this->is_circular_)
- bt1 = gogo->backend()->circular_pointer_type(bt, true);
if (!gogo->backend()->set_placeholder_pointer_type(bt, bt1))
bt = gogo->backend()->error_type();
return bt;
@@ -10803,15 +10798,10 @@ Named_type::do_get_backend(Gogo* gogo)
// Don't build a circular data structure. GENERIC can't handle
// it.
if (this->seen_in_get_backend_)
- {
- this->is_circular_ = true;
- return gogo->backend()->circular_pointer_type(bt, false);
- }
+ return gogo->backend()->circular_pointer_type(bt, false);
this->seen_in_get_backend_ = true;
bt1 = Type::get_named_base_btype(gogo, base);
this->seen_in_get_backend_ = false;
- if (this->is_circular_)
- bt1 = gogo->backend()->circular_pointer_type(bt, false);
if (!gogo->backend()->set_placeholder_pointer_type(bt, bt1))
bt = gogo->backend()->error_type();
return bt;
Index: gcc/go/gofrontend/types.h
===================================================================
--- gcc/go/gofrontend/types.h (revision 262658)
+++ gcc/go/gofrontend/types.h (working copy)
@@ -3243,8 +3243,8 @@ class Named_type : public Type
interface_method_tables_(NULL), pointer_interface_method_tables_(NULL),
location_(location), named_btype_(NULL), dependencies_(),
is_alias_(false), is_visible_(true), is_error_(false), in_heap_(true),
- is_placeholder_(false), is_converted_(false), is_circular_(false),
- is_verified_(false), seen_(false), seen_in_compare_is_identity_(false),
+ is_placeholder_(false), is_converted_(false), is_verified_(false),
+ seen_(false), seen_in_compare_is_identity_(false),
seen_in_get_backend_(false), seen_alias_(false)
{ }
@@ -3345,12 +3345,6 @@ class Named_type : public Type
is_valid() const
{ return !this->is_error_; }
- // Whether this is a circular type: a pointer or function type that
- // refers to itself, which is not possible in C.
- bool
- is_circular() const
- { return this->is_circular_; }
-
// Return the base type for this type.
Type*
named_base();
@@ -3557,9 +3551,6 @@ class Named_type : public Type
// Whether this type has been converted to the backend
// representation. Implies that is_placeholder_ is false.
bool is_converted_;
- // Whether this is a pointer or function type which refers to the
- // type itself.
- bool is_circular_;
// Whether this type has been verified.
bool is_verified_;
// In a recursive operation such as has_pointer, this flag is used
