1 files changed, 347 insertions, 12 deletions

diff --git a/gcc/graphviz.h b/gcc/graphviz.h
index 9a1ca04..5943589 100644
--- a/gcc/graphviz.h
+++ b/gcc/graphviz.h
@@ -23,10 +23,356 @@ along with GCC; see the file COPYING3.  If not see
 
 #include "pretty-print.h" /* for ATTRIBUTE_GCC_PPDIAG.  */
 
+namespace xml { class node; }
+
+namespace dot {
+
+/* A class for writing .dot output to a pretty_printer with
+   indentation to show nesting.  */
+
+class writer {
+public:
+  writer (pretty_printer &pp);
+
+  void indent () { m_indent++; }
+  void outdent () { m_indent--; }
+
+  void write_indent ();
+
+  void write_character (char ch)
+  {
+    pp_character (&m_pp, ch);
+  }
+  void write_string (const char *str)
+  {
+    pp_string (&m_pp, str);
+  }
+  void write_newline ()
+  {
+    pp_newline (&m_pp);
+  }
+
+  pretty_printer *get_pp () const { return &m_pp; }
+
+ private:
+  pretty_printer &m_pp;
+  int m_indent;
+};
+
+// An AST for the dot language
+// See https://graphviz.org/doc/info/lang.html
+
+// Forward decls
+
+struct id;
+struct node_id;
+struct port;
+struct kv_pair;
+struct graph;
+struct attr_list;
+struct stmt_list;
+struct stmt;
+  struct node_stmt;
+  struct attr_stmt;
+  struct kv_stmt;
+  struct edge_stmt;
+  struct subgraph;
+
+// Decls
+
+struct ast_node
+{
+  virtual ~ast_node () {}
+  virtual void print (writer &w) const = 0;
+
+  void dump () const;
+};
+
+struct id : public ast_node
+{
+  enum class kind
+  {
+    identifier,
+    quoted,
+    html
+  };
+
+  id (std::string str);
+
+  /* For HTML labels: see https://graphviz.org/doc/info/shapes.html#html  */
+  id (const xml::node &n);
+
+  void print (writer &w) const final override;
+
+  static bool is_identifier_p (const char *);
+
+  std::string m_str;
+  enum kind m_kind;
+};
+
+/* ID '=' ID */
+
+struct kv_pair : ast_node
+{
+  kv_pair (id key, id value)
+  : m_key (std::move (key)),
+    m_value (std::move (value))
+  {
+  }
+
+  void print (writer &w) const final override;
+
+  id m_key;
+  id m_value;
+};
+
+/* attr_list: '[' [ a_list ] ']' [ attr_list ] */
+
+struct attr_list : public ast_node
+{
+  void print (writer &w) const;
+  void add (id key, id value)
+  {
+    m_kvs.push_back ({std::move (key), std::move (value)});
+  }
+
+  std::vector<kv_pair> m_kvs;
+};
+
+/* stmt_list : [ stmt [ ';' ] stmt_list ] */
+
+struct stmt_list : public ast_node
+{
+  void print (writer &w) const final override;
+  void add_stmt (std::unique_ptr<stmt> s)
+  {
+    m_stmts.push_back (std::move (s));
+  }
+  void add_edge (node_id src_id, node_id dst_id);
+  void add_attr (id key, id value);
+
+  std::vector<std::unique_ptr<stmt>> m_stmts;
+};
+
+/* graph : [ strict ] (graph | digraph) [ ID ] '{' stmt_list '}'  */
+
+struct graph : public ast_node
+{
+  graph ()
+  : m_id (nullptr)
+  {
+  }
+
+  graph (id id_)
+  : m_id (std::make_unique<id> (std::move (id_)))
+  {
+  }
+
+  void print (writer &w) const final override;
+
+  void add_stmt (std::unique_ptr<stmt> s)
+  {
+    m_stmt_list.add_stmt (std::move (s));
+  }
+
+  std::unique_ptr<id> m_id; // optional
+  stmt_list m_stmt_list;
+};
+
+/* Abstract base class.
+     stmt : node_stmt
+	  | edge_stmt
+	  | attr_stmt
+	  | ID '=' ID ("kv_stmt")
+	  | subgraph  */
+
+struct stmt
+{
+  virtual ~stmt () {}
+  virtual void print (writer &w) const = 0;
+};
+
+struct stmt_with_attr_list : public stmt
+{
+  void set_attr (id key, id value)
+  {
+    m_attrs.add (std::move (key), std::move (value));
+  }
+  void set_label (dot::id label);
+
+  attr_list m_attrs;
+};
+
+struct node_stmt : public stmt_with_attr_list
+{
+  node_stmt (id id_)
+  : m_id (id_)
+  {
+  }
+
+  void print (writer &w) const final override;
+
+  id m_id;
+};
+
+struct attr_stmt : public stmt_with_attr_list
+{
+  enum class kind { graph, node, edge };
+
+  attr_stmt (enum kind kind_)
+  : m_kind (kind_)
+  {
+  }
+
+  void print (writer &w) const final override;
+
+  enum kind m_kind;
+};
+
+/* "ID '=' ID" as a stmt.  */
+
+struct kv_stmt : public stmt
+{
+  kv_stmt (kv_pair kv)
+  : m_kv (std::move (kv))
+  {}
+
+  void print (writer &w) const final override;
+
+  kv_pair m_kv;
+};
+
+/* node_id : ID [ port ] */
+
+enum class compass_pt
+{
+ n, ne, e, se, s, sw, w, nw, c
+ /* "_" clashes with intl macro */
+};
+
+/* port : ':' ID [ ':' compass_pt ]
+        | ':' compass_pt
+*/
+
+struct port : public ast_node
+{
+  port (id id_)
+  : m_id (std::make_unique<id> (std::move (id_))),
+    m_compass_pt (nullptr)
+  {
+  }
+
+  port (enum compass_pt compass_pt_)
+  : m_id (nullptr),
+    m_compass_pt (std::make_unique<compass_pt> (compass_pt_))
+  {
+  }
+
+  port (id id_,
+	enum compass_pt compass_pt_)
+  : m_id (std::make_unique<id> (std::move (id_))),
+    m_compass_pt (std::make_unique<compass_pt> (compass_pt_))
+  {
+  }
+
+  port (const port &other)
+  : m_id (nullptr),
+    m_compass_pt (nullptr)
+  {
+    if (other.m_id)
+      m_id = std::make_unique<id> (*other.m_id);
+    if (other.m_compass_pt)
+      m_compass_pt = std::make_unique<enum compass_pt> (*other.m_compass_pt);
+  }
+
+  void print (writer &w) const final override;
+
+  std::unique_ptr<id> m_id; // would be std::optional
+  std::unique_ptr<enum compass_pt> m_compass_pt; // would be std::optional
+};
+
+struct node_id : public ast_node
+{
+  node_id (id id_)
+  : m_id (id_),
+    m_port (nullptr)
+  {
+  }
+  node_id (id id_, port port_)
+  : m_id (id_),
+    m_port (std::make_unique<port> (std::move (port_)))
+  {
+  }
+  node_id (const node_id &other)
+  : m_id (other.m_id),
+    m_port (nullptr)
+  {
+    if (other.m_port)
+      m_port = std::make_unique<port> (*other.m_port);
+  }
+
+  void print (writer &w) const final override;
+
+  id m_id;
+  std::unique_ptr<port> m_port; // would be std::optional
+};
+
+/* The full grammar for edge_stmt is:
+     edge_stmt  : (node_id | subgraph) edgeRHS [ attr_list ]
+     edgeRHS    : edgeop (node_id | subgraph) [ edgeRHS ]
+   This class support the subsets where all are "node_id", rather than
+   "subgraph", and doesn't yet support "port" giving effectively:
+      node_id (edgeop node_id)+ [ attr_list]
+ */
+
+struct edge_stmt : public stmt_with_attr_list
+{
+  edge_stmt (node_id src_id, node_id dst_id)
+  {
+    m_node_ids.push_back (std::move (src_id));
+    m_node_ids.push_back (std::move (dst_id));
+  }
+
+  void print (writer &w) const final override;
+
+  std::vector<node_id> m_node_ids; // should have 2 or more elements
+};
+
+/* [ subgraph [ ID ] ] '{' stmt_list '}' */
+
+struct subgraph : public stmt
+{
+  subgraph (id id_)
+  : m_id (id_)
+  {
+  }
+
+  void print (writer &w) const final override;
+
+  void add_stmt (std::unique_ptr<stmt> s)
+  {
+    m_stmt_list.add_stmt (std::move (s));
+  }
+  void add_attr (id key, id value)
+  {
+    m_stmt_list.add_stmt
+      (std::make_unique <kv_stmt> (kv_pair (std::move (key),
+					    std::move (value))));
+  }
+
+  id m_id;
+  stmt_list m_stmt_list;
+};
+
+extern std::unique_ptr<xml::node>
+make_svg_from_graph (const graph &g);
+
+} // namespace dot
+
 /* A class for writing .dot output to a pretty_printer with
    indentation to show nesting.  */
 
-class graphviz_out {
+class graphviz_out : public dot::writer {
  public:
   graphviz_out (pretty_printer *pp);
 
@@ -35,11 +381,6 @@ class graphviz_out {
   void println (const char *fmt, ...)
     ATTRIBUTE_GCC_PPDIAG(2,3);
 
-  void indent () { m_indent++; }
-  void outdent () { m_indent--; }
-
-  void write_indent ();
-
   void begin_tr ();
   void end_tr ();
 
@@ -48,12 +389,6 @@ class graphviz_out {
 
   void begin_trtd ();
   void end_tdtr ();
-
-  pretty_printer *get_pp () const { return m_pp; }
-
- private:
-  pretty_printer *m_pp;
-  int m_indent;
 };
 
 #endif /* GCC_GRAPHVIZ_H */