From a4721e94e844615f9a834099437254b46ccbc9fb Mon Sep 17 00:00:00 2001
From: David Malcolm <dmalcolm@redhat.com>
Date: Wed, 6 Apr 2016 21:50:31 -0400
Subject: [PATCH 21/55] FIXME: handle insns with NULL basic block

---
 gcc/print-rtl.c       |  2 ++
 gcc/read-md.c         | 40 ++++++++++++++++++++++++++++++++++------
 gcc/read-md.h         |  3 ++-
 gcc/read-rtl.c        |  4 ++--
 test-loop.cleaned.rtl |  2 +-
 5 files changed, 41 insertions(+), 10 deletions(-)

diff --git a/gcc/print-rtl.c b/gcc/print-rtl.c
index 85d9b8d..b918195 100644
--- a/gcc/print-rtl.c
+++ b/gcc/print-rtl.c
@@ -586,6 +586,8 @@ print_rtx (const_rtx in_rtx)
 #ifndef GENERATOR_FILE
 	if (XBBDEF (in_rtx, i))
 	  fprintf (outfile, " %i", XBBDEF (in_rtx, i)->index);
+	else
+	  fprintf (outfile, " (nil)");
 #endif
 	break;
 
diff --git a/gcc/read-md.c b/gcc/read-md.c
index ec6fe69..0975758 100644
--- a/gcc/read-md.c
+++ b/gcc/read-md.c
@@ -99,6 +99,8 @@ static htab_t md_constants;
 /* A table of enum_type structures, hashed by name.  */
 static htab_t enum_types;
 
+static void read_skip_construct (int depth, file_location loc);
+
 /* Given an object that starts with a char * name field, return a hash
    code for its name.  */
 
@@ -338,7 +340,7 @@ fatal_with_file_and_line (const char *msg, ...)
   va_end (ap);
 
 #ifndef GENERATOR_FILE
-  file_location loc = rtx_reader_ptr->get_currrent_location ();
+  file_location loc = rtx_reader_ptr->get_current_location ();
   inform (loc, "here");
 #endif
 
@@ -410,8 +412,8 @@ read_skip_spaces (void)
 /* Read an rtx code name into NAME.  It is terminated by any of the
    punctuation chars of rtx printed syntax.  */
 
-void
-read_name (struct md_name *name)
+static bool
+read_name_1 (struct md_name *name)
 {
   int c;
   size_t i;
@@ -450,7 +452,7 @@ read_name (struct md_name *name)
     }
 
   if (i == 0)
-    fatal_with_file_and_line ("missing name or number");
+    return false;
 
   name->buffer[i] = 0;
   name->string = name->buffer;
@@ -471,6 +473,32 @@ read_name (struct md_name *name)
 	}
       while (def);
     }
+
+  return true;
+}
+
+/* Read an rtx code name into NAME.  It is terminated by any of the
+   punctuation chars of rtx printed syntax.  */
+
+void
+read_name (struct md_name *name)
+{
+  if (!read_name_1 (name))
+    fatal_with_file_and_line ("missing name or number");
+}
+
+void
+read_name_or_nil (struct md_name *name)
+{
+  if (!read_name_1 (name))
+    {
+      file_location loc = rtx_reader_ptr->get_current_location ();
+      read_skip_construct (0, loc);
+      /* Skip the ')'.  */
+      read_char ();
+      name->buffer[0] = 0;
+      name->string = name->buffer;
+    }
 }
 
 /* Subroutine of the string readers.  Handles backslash escapes.
@@ -1032,7 +1060,7 @@ rtx_reader::handle_file ()
   read_md_lineno = 1;
   while ((c = read_skip_spaces ()) != EOF)
     {
-      file_location loc = get_currrent_location ();
+      file_location loc = get_current_location ();
       if (c != '(')
 	fatal_expected_char ('(', c);
 
@@ -1078,7 +1106,7 @@ rtx_reader::handle_toplevel_file ()
 }
 
 file_location
-rtx_reader::get_currrent_location () const
+rtx_reader::get_current_location () const
 {
   return linemap_position_for_line_and_column (m_line_table,
 					       m_current_linemap,
diff --git a/gcc/read-md.h b/gcc/read-md.h
index 0cc52f6..c0ace66 100644
--- a/gcc/read-md.h
+++ b/gcc/read-md.h
@@ -95,7 +95,7 @@ class rtx_reader
      unread character is the optional space after the directive name.  */
   virtual void handle_unknown_directive (file_location, const char *) = 0;
 
-  file_location get_currrent_location () const;
+  file_location get_current_location () const;
 
  private:
   void handle_file ();
@@ -162,6 +162,7 @@ extern void fatal_with_file_and_line (const char *, ...)
 extern void fatal_expected_char (int, int) ATTRIBUTE_NORETURN;
 extern int read_skip_spaces (void);
 extern void read_name (struct md_name *);
+extern void read_name_or_nil (struct md_name *);
 extern char *read_quoted_string (void);
 extern char *read_string (int);
 extern int n_comma_elts (const char *);
diff --git a/gcc/read-rtl.c b/gcc/read-rtl.c
index 3f902283..57adf42 100644
--- a/gcc/read-rtl.c
+++ b/gcc/read-rtl.c
@@ -1540,8 +1540,8 @@ read_rtx_code (const char *code_name)
 
       case 'B':
 	{
-	  read_name (&name);
-	  fprintf (stderr, "FIXME: do something with basic block ID: %s\n",
+	  read_name_or_nil (&name);
+	  fprintf (stderr, "FIXME: do something with basic block ID: '%s'\n",
 		   name.string);
 	}
 	break;
diff --git a/test-loop.cleaned.rtl b/test-loop.cleaned.rtl
index 1a928f9..2f39d1f 100644
--- a/test-loop.cleaned.rtl
+++ b/test-loop.cleaned.rtl
@@ -12,7 +12,7 @@
 ;;
 ;; Full RTL generated for this function:
 ;;
-;;(note 1 0 6 NOTE_INSN_DELETED)
+(note 1 0 6 (nil) NOTE_INSN_DELETED)
 ;;(note 6 1 2 2 [bb 2] NOTE_INSN_BASIC_BLOCK)
 (insn 2 6 3 2 (set (mem/c:SI (plus:DI (reg/f:DI 82 virtual-stack-vars)
                 (const_int -4 [0xfffffffffffffffc])) [1 i+0 S4 A32])
-- 
1.8.5.3