This patch to the Go frontend by Than McIntosh adds a new debugging
helper function debug_go_type. This is intended to display the
contents of a Type object in a way useful to debugging a run of the
compiler. Prior to this the only useful alternative for debugging
types was invoking the mangled_name method, which has problems (for
example, won't work on interface types prior to finalizing of
methods). This is a "deep" dump, meaning that all types reachable
from the type passed to debug_go_type() will be printed out.
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 269619)
+++ gcc/go/gofrontend/MERGE (working copy)
@@ -1,4 +1,4 @@
-3106ec19626d75d8275be16c86421132548fa13e
+565b5cd0f49a00ca20941ea042c07ebe6ddf3553
The first line of this file holds the git revision number of the last
merge done from the gofrontend repository.
Index: gcc/go/gofrontend/ast-dump.cc
===================================================================
--- gcc/go/gofrontend/ast-dump.cc (revision 269619)
+++ gcc/go/gofrontend/ast-dump.cc (working copy)
@@ -8,6 +8,7 @@
#include <iostream>
#include <fstream>
+#include <sstream>
#include "gogo.h"
#include "expressions.h"
@@ -580,3 +581,382 @@ debug_go_block_deep(const Block* block)
Block* ncblock = const_cast<Block*>(block);
adc.dump_block(ncblock);
}
+
+class Type_dumper
+{
+ typedef Unordered_map(const Type*, unsigned) idx_map;
+ public:
+ Type_dumper(const Type* type)
+ : top_(type), ntypes_(0)
+ {
+ this->worklist_.push_back(type);
+ }
+
+ void visit();
+
+ std::string stringResult() { return ss_.str(); }
+
+ private:
+ void emitpre(unsigned tag, const Type* addr);
+ void typeref(const char*, const Type*, const char *);
+ void visit_forward_declaration_type(const Forward_declaration_type* fdt);
+ void visit_function_type(const Function_type* ft);
+ void visit_struct_type(const Struct_type* st);
+ void visit_array_type(const Array_type* at);
+ void visit_map_type(const Map_type* mt);
+ void visit_channel_type(const Channel_type* mt);
+ void visit_interface_type(const Interface_type* mt);
+ void visit_methods(const Typed_identifier_list* methods,
+ const char *tag);
+ std::pair<bool, unsigned> lookup(const Type*);
+
+ static constexpr unsigned notag = 0xffffffff;
+
+ private:
+ const Type* top_;
+ idx_map types_;
+ unsigned ntypes_;
+ std::list<const Type*> worklist_;
+ std::ostringstream ss_;
+};
+
+// Look up a type, installing it in 'types_'. Return is <found, N>
+// where 'found' is true if type had been previously recorded, and N
+// is the index/tag assigned to N. The input argument is appended to
+// the work list if this is the first time we've seen it.
+
+std::pair<bool, unsigned> Type_dumper::lookup(const Type* t)
+{
+ std::pair<const Type*, unsigned> entry = std::make_pair(t, this->ntypes_);
+ std::pair<idx_map::iterator, bool> ins = this->types_.insert(entry);
+ if (ins.second)
+ {
+ this->ntypes_++;
+ if (t != this->top_)
+ this->worklist_.push_back(t);
+ }
+ return std::make_pair(ins.second, ins.first->second);
+}
+
+// Emit preamble prior to dumping a type, including the type
+// pointer itself and the tag we've assigned it. If no
+// tag is specified (via special "notag" value) and/or the
+// pointer is null, then just emit an equivalent amount
+// of spaces.
+
+void Type_dumper::emitpre(unsigned tag, const Type* ptr)
+{
+ char tbuf[50], pbuf[50], buf[200];
+
+ tbuf[0] = '\0';
+ if (tag != notag)
+ snprintf(tbuf, sizeof tbuf, "T%u", tag);
+
+ pbuf[0] = '\0';
+ if (ptr != NULL)
+ snprintf(pbuf, sizeof pbuf, "%p", (const void*) ptr);
+
+ snprintf(buf, sizeof buf, "%8s %16s ", tbuf, pbuf);
+ this->ss_ << buf;
+}
+
+// Emit a reference to a type into the dump buffer. In most cases this means
+// just the type tag, but for named types we also emit the name, and for
+// simple/primitive types (ex: int64) we emit the type itself. If "pref" is
+// non-NULL, emit the string prior to the reference, and if "suf" is non-NULL,
+// emit it following the reference.
+
+void Type_dumper::typeref(const char* pref, const Type* t, const char* suf)
+{
+ if (pref != NULL)
+ this->ss_ << pref;
+ std::pair<bool, unsigned> p = this->lookup(t);
+ unsigned tag = p.second;
+ switch (t->classification())
+ {
+ case Type::TYPE_NAMED:
+ {
+ const Named_type* nt = t->named_type();
+ const Named_object* no = nt->named_object();
+ this->ss_ << "'" << no->message_name() << "' -> ";
+ const Type* underlying = nt->real_type();
+ this->typeref(NULL, underlying, NULL);
+ break;
+ }
+ case Type::TYPE_POINTER:
+ this->typeref("*", t->points_to(), NULL);
+ break;
+ case Type::TYPE_ERROR:
+ this->ss_ << "error_type";
+ break;
+ case Type::TYPE_INTEGER:
+ {
+ const Integer_type* it = t->integer_type();
+ if (it->is_abstract())
+ this->ss_ << "abstract_int";
+ else
+ this->ss_ << (it->is_unsigned() ? "u" : "") << "int" << it->bits();
+ break;
+ }
+ case Type::TYPE_FLOAT:
+ {
+ const Float_type* ft = t->float_type();
+ if (ft->is_abstract())
+ this->ss_ << "abstract_float";
+ else
+ this->ss_ << "float" << ft->bits();
+ break;
+ }
+ case Type::TYPE_COMPLEX:
+ {
+ const Complex_type* ct = t->complex_type();
+ if (ct->is_abstract())
+ this->ss_ << "abstract_complex";
+ else
+ this->ss_ << "complex" << ct->bits();
+ break;
+ }
+ case Type::TYPE_BOOLEAN:
+ this->ss_ << "bool";
+ break;
+ case Type::TYPE_STRING:
+ this->ss_ << "string";
+ break;
+ case Type::TYPE_NIL:
+ this->ss_ << "nil_type";
+ break;
+ case Type::TYPE_VOID:
+ this->ss_ << "void_type";
+ break;
+ case Type::TYPE_FUNCTION:
+ case Type::TYPE_STRUCT:
+ case Type::TYPE_ARRAY:
+ case Type::TYPE_MAP:
+ case Type::TYPE_CHANNEL:
+ case Type::TYPE_FORWARD:
+ case Type::TYPE_INTERFACE:
+ this->ss_ << "T" << tag;
+ break;
+
+ default:
+ // This is a debugging routine, so instead of a go_unreachable()
+ // issue a warning/error, to allow for the possibility that the
+ // compiler we're debugging is in a bad state.
+ this->ss_ << "<??? " << ((unsigned)t->classification()) << "> "
+ << "T" << tag;
+ }
+ if (suf != NULL)
+ this->ss_ << suf;
+}
+
+void Type_dumper::visit_forward_declaration_type(const
Forward_declaration_type* fdt)
+{
+ this->ss_ << "forward_declaration_type ";
+ if (fdt->is_defined())
+ this->typeref("-> ", fdt->real_type(), NULL);
+ else
+ this->ss_ << "'" << fdt->name() << "'";
+ this->ss_ << "\n";
+}
+
+void Type_dumper::visit_function_type(const Function_type* ft)
+{
+ this->ss_ << "function\n";
+ const Typed_identifier* rec = ft->receiver();
+ if (rec != NULL)
+ {
+ this->emitpre(notag, NULL);
+ this->typeref("receiver ", rec->type(), NULL);
+ }
+ const Typed_identifier_list* parameters = ft->parameters();
+ if (parameters != NULL)
+ {
+ for (Typed_identifier_list::const_iterator p = parameters->begin();
+ p != parameters->end();
+ ++p)
+ {
+ this->emitpre(notag, NULL);
+ this->typeref(" param ", p->type(), "\n");
+ }
+ }
+ const Typed_identifier_list* results = ft->results();
+ if (results != NULL)
+ {
+ for (Typed_identifier_list::const_iterator p = results->begin();
+ p != results->end();
+ ++p)
+ {
+ this->emitpre(notag, NULL);
+ this->typeref(" result ", p->type(), "\n");
+ }
+ }
+}
+
+void Type_dumper::visit_struct_type(const Struct_type* st)
+{
+ this->ss_ << "struct\n";
+ const Struct_field_list* fields = st->fields();
+ if (fields != NULL)
+ {
+ for (Struct_field_list::const_iterator p = fields->begin();
+ p != fields->end();
+ ++p)
+ {
+ this->emitpre(notag, NULL);
+ this->typeref(" field ", p->type(), "\n");
+ }
+ }
+}
+
+void Type_dumper::visit_array_type(const Array_type* at)
+{
+ this->ss_ << "array [";
+ if (at->length() != NULL)
+ {
+ int64_t len = 0;
+ if (at->int_length(&len))
+ this->ss_ << len;
+ }
+ this->typeref("] ", at->element_type(), "\n");
+}
+
+void Type_dumper::visit_map_type(const Map_type* mt)
+{
+ this->ss_ << "map [";
+ this->typeref(NULL, mt->key_type(), NULL);
+ this->typeref("] ", mt->val_type(), "\n");
+}
+
+void Type_dumper::visit_methods(const Typed_identifier_list* methods,
+ const char *tag)
+{
+ if (tag != NULL)
+ {
+ this->emitpre(notag, NULL);
+ this->ss_ << tag << "\n";
+ }
+ for (Typed_identifier_list::const_iterator p = methods->begin();
+ p != methods->end();
+ ++p)
+ {
+ this->emitpre(notag, NULL);
+ if (p->name().empty())
+ this->typeref(" embedded method ", p->type(), "\n");
+ else
+ {
+ this->ss_ << " method '" << p->name() << "' ";
+ this->typeref(NULL, p->type(), "\n");
+ }
+ }
+}
+
+void Type_dumper::visit_interface_type(const Interface_type* it)
+{
+ const Typed_identifier_list* methods =
+ (it->methods_are_finalized() ? it->methods() : it->local_methods());
+ if (methods == NULL)
+ {
+ this->ss_ << "empty_interface\n";
+ return;
+ }
+ this->ss_ << "interface";
+ if (! it->methods_are_finalized())
+ {
+ this->ss_ << " [unfinalized]\n";
+ visit_methods(it->local_methods(), NULL);
+ }
+ else
+ {
+ this->ss_ << "\n";
+ visit_methods(it->local_methods(), "[parse_methods]");
+ visit_methods(it->methods(), "[all_methods]");
+ }
+}
+
+void Type_dumper::visit_channel_type(const Channel_type* ct)
+{
+ this->ss_ << "channel {";
+ if (ct->may_send())
+ this->ss_ << " send";
+ if (ct->may_receive())
+ this->ss_ << " receive";
+ this->typeref(" } ", ct->element_type(), "\n");
+}
+
+void Type_dumper::visit()
+{
+ while (! this->worklist_.empty()) {
+ const Type* t = this->worklist_.front();
+ this->worklist_.pop_front();
+
+ std::pair<bool, unsigned> p = this->lookup(t);
+ unsigned tag = p.second;
+ this->emitpre(tag, t);
+
+ switch(t->classification())
+ {
+ case Type::TYPE_ERROR:
+ case Type::TYPE_INTEGER:
+ case Type::TYPE_FLOAT:
+ case Type::TYPE_COMPLEX:
+ case Type::TYPE_BOOLEAN:
+ case Type::TYPE_STRING:
+ case Type::TYPE_VOID:
+ case Type::TYPE_POINTER:
+ case Type::TYPE_NIL:
+ case Type::TYPE_NAMED:
+ this->typeref(NULL, t, "\n");
+ break;
+ case Type::TYPE_FORWARD:
+ this->visit_forward_declaration_type(t->forward_declaration_type());
+ break;
+
+ case Type::TYPE_FUNCTION:
+ this->visit_function_type(t->function_type());
+ break;
+ case Type::TYPE_STRUCT:
+ this->visit_struct_type(t->struct_type());
+ break;
+ case Type::TYPE_ARRAY:
+ this->visit_array_type(t->array_type());
+ break;
+ case Type::TYPE_MAP:
+ this->visit_map_type(t->map_type());
+ break;
+ case Type::TYPE_CHANNEL:
+ this->visit_channel_type(t->channel_type());
+ break;
+ case Type::TYPE_INTERFACE:
+ this->visit_interface_type(t->interface_type());
+ break;
+ default:
+ // This is a debugging routine, so instead of a go_unreachable()
+ // issue a warning/error, to allow for the possibility that the
+ // compiler we're debugging is in a bad state.
+ this->ss_ << "<unknown/unrecognized classification "
+ << ((unsigned)t->classification()) << ">\n";
+ }
+ }
+}
+
+// Dump a Go type for debugging purposes. This is a deep as opposed
+// to shallow dump; all of the types reachable from the specified
+// type will be dumped in addition to the type itself.
+
+void debug_go_type(const Type* type)
+{
+ if (type == NULL)
+ {
+ std::cerr << "<NULL type>\n";
+ return;
+ }
+ Type_dumper dumper(type);
+ dumper.visit();
+ std::cerr << dumper.stringResult();
+}
+
+void debug_go_type(Type* type)
+{
+ const Type* ctype = type;
+ debug_go_type(ctype);
+}
Index: gcc/go/gofrontend/types.cc
===================================================================
--- gcc/go/gofrontend/types.cc (revision 269619)
+++ gcc/go/gofrontend/types.cc (working copy)
@@ -6951,7 +6951,7 @@ Type::make_struct_type(Struct_field_list
// called for a slice.
bool
-Array_type::int_length(int64_t* plen)
+Array_type::int_length(int64_t* plen) const
{
go_assert(this->length_ != NULL);
Numeric_constant nc;
Index: gcc/go/gofrontend/types.h
===================================================================
--- gcc/go/gofrontend/types.h (revision 269619)
+++ gcc/go/gofrontend/types.h (working copy)
@@ -2706,7 +2706,7 @@ class Array_type : public Type
// length can not be determined. This will assert if called for a
// slice.
bool
- int_length(int64_t* plen);
+ int_length(int64_t* plen) const;
// Whether this type is identical with T.
bool
@@ -3160,6 +3160,11 @@ class Interface_type : public Type
static Type*
make_interface_type_descriptor_type();
+ // Return whether methods are finalized for this interface.
+ bool
+ methods_are_finalized() const
+ { return this->methods_are_finalized_; }
+
protected:
int
do_traverse(Traverse*);
