[PATCH 4/9] (approved) Add some functions for use by the RTL frontend.

[David Malcolm <dmalcolm at redhat dot com>]

An earlier version of this was approved by Bernd as:
  https://gcc.gnu.org/ml/gcc-patches/2016-10/msg00280.html
and the changes since then probably fall under the "obvious" rule.

gcc/ChangeLog:
	* read-md.c (rtx_reader::require_char): New method.
	(require_char_ws): Convert from function to...
	(rtx_reader::require_char_ws): ...method.
	(rtx_reader::require_word_ws): New method.
	* read-md.h (rtx_reader::require_char): New method decl.
	(require_char_ws): Remove global decl in favor of...
	(rtx_reader::require_char_ws): ...new method decl.
	(rtx_reader::require_word_ws): New method decl.
	(rtx_reader::peek_char): New method decl.
---
 gcc/read-md.c | 35 ++++++++++++++++++++++++++++++++++-
 gcc/read-md.h |  5 ++++-
 2 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/gcc/read-md.c b/gcc/read-md.c
index 6fe2600..095075f 100644
--- a/gcc/read-md.c
+++ b/gcc/read-md.c
@@ -340,17 +340,40 @@ read_skip_spaces (void)
     }
 }
 
+/* Consume the next character, issuing a fatal error if it is not
+   EXPECTED.  */
+
+void
+rtx_reader::require_char (char expected)
+{
+  int ch = read_char ();
+  if (ch != expected)
+    fatal_expected_char (expected, ch);
+}
+
 /* Consume any whitespace, then consume the next non-whitespace
    character, issuing a fatal error if it is not EXPECTED.  */
 
 void
-require_char_ws (char expected)
+rtx_reader::require_char_ws (char expected)
 {
   int ch = read_skip_spaces ();
   if (ch != expected)
     fatal_expected_char (expected, ch);
 }
 
+/* Consume any whitespace, then consume the next word (as per read_name),
+   issuing a fatal error if it is not EXPECTED.  */
+
+void
+rtx_reader::require_word_ws (const char *expected)
+{
+  struct md_name name;
+  read_name (&name);
+  if (strcmp (name.string, expected))
+    fatal_with_file_and_line ("missing '%s'", expected);
+}
+
 /* Read the next character from the file.  */
 
 int
@@ -386,6 +409,16 @@ rtx_reader::unread_char (int ch)
   ungetc (ch, m_read_md_file);
 }
 
+/* Peek at the next character from the file without consuming it.  */
+
+int
+rtx_reader::peek_char (void)
+{
+  int ch = read_char ();
+  unread_char (ch);
+  return ch;
+}
+
 /* Read an rtx code name into NAME.  It is terminated by any of the
    punctuation chars of rtx printed syntax.  */
 
diff --git a/gcc/read-md.h b/gcc/read-md.h
index 996b514..06b89b4 100644
--- a/gcc/read-md.h
+++ b/gcc/read-md.h
@@ -116,6 +116,10 @@ class rtx_reader
   char *read_braced_string ();
   char *read_string (int star_if_braced);
   void read_skip_construct (int depth, file_location loc);
+  void require_char (char expected);
+  void require_char_ws (char expected);
+  void require_word_ws (const char *expected);
+  int peek_char (void);
 
   void set_md_ptr_loc (const void *ptr, const char *filename, int lineno);
   const struct ptr_loc *get_md_ptr_loc (const void *ptr);
@@ -269,7 +273,6 @@ extern void fatal_with_file_and_line (const char *, ...)
   ATTRIBUTE_PRINTF_1 ATTRIBUTE_NORETURN;
 extern void fatal_expected_char (int, int) ATTRIBUTE_NORETURN;
 extern int read_skip_spaces (void);
-extern void require_char_ws (char expected);
 extern int n_comma_elts (const char *);
 extern const char *scan_comma_elt (const char **);
 extern void upcase_string (char *);
-- 
1.8.5.3