Add "optinfo" framework

This patch implements a way to consolidate dump_* calls into
optinfo objects, as enabling work towards being able to write out
optimization records to a file.

The patch adds the support for building optinfo instances from dump_*
calls, but leaves implementing any *users* of them to followup patches.

gcc/ChangeLog:
	* Makefile.in (OBJS): Add optinfo.o.
	* coretypes.h (class symtab_node): New forward decl.
	(struct cgraph_node): New forward decl.
	(class varpool_node): New forward decl.
	* dump-context.h: New file.
	* dumpfile.c: Include "optinfo.h", "dump-context.h", "cgraph.h",
	"tree-pass.h".
	(refresh_dumps_are_enabled): Use optinfo_enabled_p.
	(set_dump_file): Call dumpfile_ensure_any_optinfo_are_flushed.
	(set_alt_dump_file): Likewise.
	(dump_context::~dump_context): New dtor.
	(dump_gimple_stmt): Move implementation to...
	(dump_context::dump_gimple_stmt): ...this new member function.
	Add the stmt to any pending optinfo, creating one if need be.
	(dump_gimple_stmt_loc): Move implementation to...
	(dump_context::dump_gimple_stmt_loc): ...this new member function.
	Start a new optinfo and add the stmt to it.
	(dump_gimple_expr): Move implementation to...
	(dump_context::dump_gimple_expr): ...this new member function.
	Add the stmt to any pending optinfo, creating one if need be.
	(dump_gimple_expr_loc): Move implementation to...
	(dump_context::dump_gimple_expr_loc): ...this new member function.
	Start a new optinfo and add the stmt to it.
	(dump_generic_expr): Move implementation to...
	(dump_context::dump_generic_expr): ...this new member function.
	Add the tree to any pending optinfo, creating one if need be.
	(dump_generic_expr_loc): Move implementation to...
	(dump_context::dump_generic_expr_loc): ...this new member
	function.  Add the tree to any pending optinfo, creating one if
	need be.
	(dump_printf): Move implementation to...
	(dump_context::dump_printf_va): ...this new member function.  Add
	the text to any pending optinfo, creating one if need be.
	(dump_printf_loc): Move implementation to...
	(dump_context::dump_printf_loc_va): ...this new member function.
	Start a new optinfo and add the stmt to it.
	(dump_dec): Move implementation to...
	(dump_context::dump_dec): ...this new member function.  Add the
	value to any pending optinfo, creating one if need be.
	(dump_context::dump_symtab_node): New member function.
	(dump_context::get_scope_depth): New member function.
	(dump_context::begin_scope): New member function.
	(dump_context::end_scope): New member function.
	(dump_context::ensure_pending_optinfo): New member function.
	(dump_context::begin_next_optinfo): New member function.
	(dump_context::end_any_optinfo): New member function.
	(dump_context::s_current): New global.
	(dump_context::s_default): New global.
	(dump_scope_depth): Delete global.
	(dumpfile_ensure_any_optinfo_are_flushed): New function.
	(dump_symtab_node): New function.
	(get_dump_scope_depth): Reimplement in terms of dump_context.
	(dump_begin_scope): Likewise.
	(dump_end_scope): Likewise.
	(selftest::temp_dump_context::temp_dump_context): New ctor.
	(selftest::temp_dump_context::~temp_dump_context): New dtor.
	(selftest::verify_item): New function.
	(ASSERT_IS_TEXT): New macro.
	(ASSERT_IS_TREE): New macro.
	(ASSERT_IS_GIMPLE): New macro.
	(selftest::test_capture_of_dump_calls): New test.
	(selftest::dumpfile_c_tests): Call it.
	* dumpfile.h (dump_printf, dump_printf_loc, dump_basic_block)
	(dump_generic_expr_loc, dump_generic_expr, dump_gimple_stmt_loc)
	(dump_gimple_stmt, dump_dec): Gather these related decls and add a
	descriptive comment.
	(dump_function, print_combine_total_stats, enable_rtl_dump_file)
	(dump_node, dump_bb): Move these unrelated decls.
	(class dump_manager): Add leading comment.
	* optinfo.cc: New file.
	* optinfo.h: New file.

From-SVN: r262891

1 files changed, 203 insertions, 0 deletions

diff --git a/gcc/optinfo.h b/gcc/optinfo.h
new file mode 100644
index 0000000..8fd5202
--- /dev/null
+++ b/gcc/optinfo.h
@@ -0,0 +1,203 @@
+/* Optimization information.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   Contributed by David Malcolm <dmalcolm@redhat.com>.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#ifndef GCC_OPTINFO_H
+#define GCC_OPTINFO_H
+
+/* An "optinfo" is a bundle of information describing part of an
+   optimization, which can be emitted to zero or more of several
+   destinations, such as:
+
+   * as a "remark" through the diagnostics subsystem
+
+   * saved to a file as an "optimization record"
+
+   Currently no such destinations are implemented.
+
+   They are generated in response to calls to the "dump_*" API in
+   dumpfile.h; repeated calls to the "dump_*" API are consolidated
+   into a pending optinfo instance, with a "dump_*_loc" starting a new
+   optinfo instance.
+
+   The data sent to the dump calls are captured within the pending optinfo
+   instance as a sequence of optinfo_items.  For example, given:
+
+      if (dump_enabled_p ())
+        {
+          dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
+                           "not vectorized: live stmt not supported: ");
+          dump_gimple_stmt (MSG_MISSED_OPTIMIZATION, TDF_SLIM, stmt, 0);
+        }
+
+   the "dump_printf_loc" call begins a new optinfo containing two items:
+   (1) a text item containing "not vectorized: live stmt not supported: "
+   (2) a gimple item for "stmt"
+
+   Dump destinations are thus able to access rich metadata about the
+   items when the optinfo is emitted to them, rather than just having plain
+   text.  For example, when saving the above optinfo to a file as an
+   "optimization record", the record could capture the source location of
+   "stmt" above, rather than just its textual form.
+
+   The currently pending optinfo is emitted and deleted:
+   * each time a "dump_*_loc" call occurs (which starts the next optinfo), or
+   * when the dump files are changed (at the end of a pass)
+
+   Dumping to an optinfo instance is non-trivial (due to building optinfo_item
+   instances), so all usage should be guarded by
+
+     if (optinfo_enabled_p ())
+
+   which is off by default.  */
+
+
+/* Forward decls.  */
+struct opt_pass;
+class optinfo_item;
+
+/* Should optinfo instances be created?
+   All creation of optinfos should be guarded by this predicate.
+   Return true if any optinfo destinations are active.  */
+
+extern bool optinfo_enabled_p ();
+
+/* Return true if any of the active optinfo destinations make use
+   of inlining information.
+   (if true, then the information is preserved).  */
+
+extern bool optinfo_wants_inlining_info_p ();
+
+/* The various kinds of optinfo.  */
+
+enum optinfo_kind
+{
+  OPTINFO_KIND_SUCCESS,
+  OPTINFO_KIND_FAILURE,
+  OPTINFO_KIND_NOTE,
+  OPTINFO_KIND_SCOPE
+};
+
+extern const char *optinfo_kind_to_string (enum optinfo_kind kind);
+
+/* A bundle of information describing part of an optimization.  */
+
+class optinfo
+{
+  friend class dump_context;
+
+ public:
+  optinfo (const dump_location_t &loc,
+	   enum optinfo_kind kind,
+	   opt_pass *pass)
+  : m_loc (loc), m_kind (kind), m_pass (pass), m_items ()
+  {}
+  ~optinfo ();
+
+  const dump_user_location_t &
+  get_user_location () const { return m_loc.get_user_location (); }
+
+  const dump_impl_location_t &
+  get_impl_location () const { return m_loc.get_impl_location (); }
+
+  enum optinfo_kind get_kind () const { return m_kind; }
+  opt_pass *get_pass () const { return m_pass; }
+  unsigned int num_items () const { return m_items.length (); }
+  const optinfo_item *get_item (unsigned int i) const { return m_items[i]; }
+
+  location_t get_location_t () const { return m_loc.get_location_t (); }
+  profile_count get_count () const { return m_loc.get_count (); }
+
+ private:
+  void emit ();
+
+  /* Pre-canned ways of manipulating the optinfo, for use by friend class
+     dump_context.  */
+  void handle_dump_file_kind (dump_flags_t);
+  void add_string (const char *str);
+  void add_printf (const char *format, ...) ATTRIBUTE_PRINTF_2;
+  void add_printf_va (const char *format, va_list ap) ATTRIBUTE_PRINTF (2, 0);
+  void add_gimple_stmt (gimple *stmt, int spc, dump_flags_t dump_flags);
+  void add_gimple_expr (gimple *stmt, int spc, dump_flags_t dump_flags);
+  void add_tree (tree node, dump_flags_t dump_flags);
+  void add_symtab_node (symtab_node *node);
+  void add_dec (const wide_int_ref &wi, signop sgn);
+
+  template<unsigned int N, typename C>
+  void add_poly_int (const poly_int<N, C> &value)
+  {
+    /* Compare with dump_dec (MSG_NOTE, ).  */
+
+    STATIC_ASSERT (poly_coeff_traits<C>::signedness >= 0);
+    signop sgn = poly_coeff_traits<C>::signedness ? SIGNED : UNSIGNED;
+
+    if (value.is_constant ())
+      add_dec (value.coeffs[0], sgn);
+    else
+      {
+	add_string ("[");
+	for (unsigned int i = 0; i < N; ++i)
+	  {
+	    add_dec (value.coeffs[i], sgn);
+	    add_string (i == N - 1 ? "]" : ",");
+	  }
+      }
+  }
+
+ private:
+  dump_location_t m_loc;
+  enum optinfo_kind m_kind;
+  opt_pass *m_pass;
+  auto_vec <optinfo_item *> m_items;
+};
+
+/* An enum for discriminating between different kinds of optinfo_item.  */
+
+enum optinfo_item_kind
+{
+  OPTINFO_ITEM_KIND_TEXT,
+  OPTINFO_ITEM_KIND_TREE,
+  OPTINFO_ITEM_KIND_GIMPLE,
+  OPTINFO_ITEM_KIND_SYMTAB_NODE
+};
+
+/* An item within an optinfo.  */
+
+class optinfo_item
+{
+ public:
+  optinfo_item (enum optinfo_item_kind kind, location_t location,
+		char *text, bool owned);
+  ~optinfo_item ();
+
+  enum optinfo_item_kind get_kind () const { return m_kind; }
+  location_t get_location () const { return m_location; }
+  const char *get_text () const { return m_text; }
+
+ private:
+  /* Metadata (e.g. for optimization records).  */
+  enum optinfo_item_kind m_kind;
+  location_t m_location;
+
+  /* The textual form of the item.  */
+  char *m_text;
+  bool m_owned;
+};
+
+#endif /* #ifndef GCC_OPTINFO_H */