Re: push parser

[Joel E. Denny]

On Sun, 31 Dec 2006, Bob Rossi wrote:

> > As far as I can tell, it's time to mv push.c yacc.c.  However, that's a 
> > major change that I should not make without some consensus.
> > 
> > Once we do that, I think we should add a new maintainer-check pass that 
> > forces yacc.c to run in that special push mode that emulates pull mode.  
> > (That pass should probably use Valgrind also.)  Otherwise, we'll have to 
> > keep setting up that mode manually in the way I've previously described:
> 
> Yeah, automating it sounds right to me too. If it's going to be a long
> time before push.c replaces yacc.c, I would think we should automate it
> right away.

Might as well, so I committed the following.  Notice that 
maintainer-push-check is not invoked by maintainer-check.  Instead, it's a 
separate version of maintainer-check.

Index: ChangeLog
===================================================================
RCS file: /sources/bison/bison/ChangeLog,v
retrieving revision 1.1641
diff -p -u -r1.1641 ChangeLog
--- ChangeLog   1 Jan 2007 00:42:21 -0000       1.1641
+++ ChangeLog   2 Jan 2007 02:03:55 -0000
@@ -1,3 +1,19 @@
+2007-01-01  Joel E. Denny  <address@hidden>
+
+       Add maintainer-push-check to run maintainer-check using push parsing in
+       place of pull parsing where available.
+       * Makefile.am (maintainer-push-check): New.
+       * data/bison.m4 (b4_use_push_for_pull_if): New.
+       * data/push.c: Redefine b4_push_if and b4_use_push_for_pull_if
+       appropriately based on their existing values.
+       (yypush_parse): Don't print push-parser-specific diagnostics if push
+       parsing is being used in place of pull parsing.
+       * data/yacc.c: If push parsing should replace pull parsing, redirect to
+       push.c.
+       * src/output.c (prepare): Check BISON_USE_PUSH_FOR_PULL environment
+       variable, and insert b4_use_push_for_pull_flag into muscles.
+       * tests/Makefile.am (maintainer-push-check): New.
+
 2006-12-31  Joel E. Denny  <address@hidden>
 
        * data/push.c (yypush_parse): Set yynew = 1 at the end of a parse
Index: Makefile.am
===================================================================
RCS file: /sources/bison/bison/Makefile.am,v
retrieving revision 1.45
diff -p -u -r1.45 Makefile.am
--- Makefile.am 26 Dec 2006 18:09:53 -0000      1.45
+++ Makefile.am 2 Jan 2007 02:03:55 -0000
@@ -1,5 +1,6 @@
 ## Process this file with automake to produce Makefile.in -*-Makefile-*-
-## Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+## Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software
+## Foundation, Inc.
 
 ## This program is free software; you can redistribute it and/or modify
 ## it under the terms of the GNU General Public License as published by
@@ -35,3 +36,7 @@ EXTRA_DIST = GNUmakefile Makefile.cfg Ma
 .PHONY: maintainer-check
 maintainer-check:
        cd tests && $(MAKE) $(AM_MAKEFLAGS) $@
+
+.PHONY: maintainer-push-check
+maintainer-push-check:
+       cd tests && $(MAKE) $(AM_MAKEFLAGS) $@
Index: data/bison.m4
===================================================================
RCS file: /sources/bison/bison/data/bison.m4,v
retrieving revision 1.3
diff -p -u -r1.3 bison.m4
--- data/bison.m4       31 Dec 2006 20:29:48 -0000      1.3
+++ data/bison.m4       2 Jan 2007 02:03:55 -0000
@@ -1,7 +1,7 @@
 m4_divert(-1)                                               -*- Autoconf -*-
 
 # Language-independent M4 Macros for Bison.
-# Copyright (C) 2002, 2004, 2005, 2006 Free Software Foundation, Inc.
+# Copyright (C) 2002, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -130,6 +130,10 @@ b4_define_flag_if([nondeterministic])      # 
 b4_define_flag_if([pull])              # Whether pull parsing is requested.
 b4_define_flag_if([pure])              # Whether the interface is pure.
 b4_define_flag_if([push])              # Whether push parsing is requested.
+b4_define_flag_if([use_push_for_pull])  # Whether push parsing should be used
+                                        # in place of pull parsing (where
+                                        # available) for the sake of the test
+                                        # suite.
 b4_define_flag_if([yacc])              # Whether POSIX Yacc is emulated.
 
 
Index: data/push.c
===================================================================
RCS file: /sources/bison/bison/data/push.c,v
retrieving revision 1.28
diff -p -u -r1.28 push.c
--- data/push.c 1 Jan 2007 00:42:21 -0000       1.28
+++ data/push.c 2 Jan 2007 02:03:55 -0000
@@ -2,8 +2,8 @@ m4_divert(-1)                           
 
 # Yacc compatible skeleton for Bison
 
-# Copyright (C) 1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005, 2006
-# Free Software Foundation, Inc.
+# Copyright (C) 1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
+# 2007 Free Software Foundation, Inc.
 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -20,6 +20,18 @@ m4_divert(-1)                           
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 # 02110-1301  USA
 
+# Handle BISON_USE_PUSH_FOR_PULL for the test suite.  So that push parsing
+# tests function as written, don't let BISON_USE_PUSH_FOR_PULL modify Bison's
+# behavior at all when push parsing is already requested.
+b4_use_push_for_pull_if([
+  b4_push_if([
+    m4_define([b4_use_push_for_pull_flag], [[0]])
+    b4_define_flag_if([use_push_for_pull])
+  ], [
+    m4_define([b4_push_flag], [[1]])
+    b4_define_flag_if([push])
+  ])])
+
 m4_include(b4_pkgdatadir/[c.m4])
 
 ## ---------------- ##
@@ -1317,8 +1329,9 @@ yybackup:
     {
 ]b4_push_if([[      if (!yyps->yynew)
         {
-          YYDPRINTF ((stderr, "Return for a new token:\n"));
-          yyresult = YYPUSH_MORE;
+]b4_use_push_for_pull_if([],
+[[          YYDPRINTF ((stderr, "Return for a new token:\n"));
+]])[          yyresult = YYPUSH_MORE;
           goto yypushreturn;
         }
       yyps->yynew = 0;
Index: data/yacc.c
===================================================================
RCS file: /sources/bison/bison/data/yacc.c,v
retrieving revision 1.156
diff -p -u -r1.156 yacc.c
--- data/yacc.c 12 Dec 2006 06:47:39 -0000      1.156
+++ data/yacc.c 2 Jan 2007 02:03:55 -0000
@@ -2,8 +2,8 @@ m4_divert(-1)                           
 
 # Yacc compatible skeleton for Bison
 
-# Copyright (C) 1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005, 2006
-# Free Software Foundation, Inc.
+# Copyright (C) 1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
+# 2007 Free Software Foundation, Inc.
 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -20,6 +20,9 @@ m4_divert(-1)                           
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 # 02110-1301  USA
 
+# Handle BISON_USE_PUSH_FOR_PULL for the test suite.
+b4_use_push_for_pull_if([m4_include(b4_pkgdatadir/[push.c])m4_exit])
+
 m4_include(b4_pkgdatadir/[c.m4])
 
 ## ---------------- ##
Index: src/output.c
===================================================================
RCS file: /sources/bison/bison/src/output.c,v
retrieving revision 1.262
diff -p -u -r1.262 output.c
--- src/output.c        31 Dec 2006 20:29:48 -0000      1.262
+++ src/output.c        2 Jan 2007 02:03:55 -0000
@@ -1,7 +1,7 @@
 /* Output the generated parsing program for Bison.
 
    Copyright (C) 1984, 1986, 1989, 1992, 2000, 2001, 2002, 2003, 2004,
-   2005, 2006 Free Software Foundation, Inc.
+   2005, 2006, 2007 Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -586,6 +586,15 @@ output_skeleton (void)
 static void
 prepare (void)
 {
+  /* BISON_USE_PUSH_FOR_PULL is for the test suite and should not be documented
+     for the user.  */
+  char const *use_push_for_pull_env = getenv ("BISON_USE_PUSH_FOR_PULL");
+  bool use_push_for_pull_flag = false;
+  if (use_push_for_pull_env != NULL
+      && use_push_for_pull_env[0] != '\0'
+      && 0 != strcmp (use_push_for_pull_env, "0"))
+    use_push_for_pull_flag = true;
+
   /* Flags. */
   MUSCLE_INSERT_BOOL ("debug_flag", debug_flag);
   MUSCLE_INSERT_BOOL ("defines_flag", defines_flag);
@@ -595,6 +604,7 @@ prepare (void)
   MUSCLE_INSERT_BOOL ("nondeterministic_flag", nondeterministic_parser);
   MUSCLE_INSERT_BOOL ("pull_flag", pull_parser);
   MUSCLE_INSERT_BOOL ("pure_flag", pure_parser);
+  MUSCLE_INSERT_BOOL ("use_push_for_pull_flag", use_push_for_pull_flag);
   MUSCLE_INSERT_BOOL ("push_flag", push_parser);
   MUSCLE_INSERT_BOOL ("synclines_flag", !no_lines_flag);
   MUSCLE_INSERT_BOOL ("tag_seen_flag", tag_seen);
Index: tests/Makefile.am
===================================================================
RCS file: /sources/bison/bison/tests/Makefile.am,v
retrieving revision 1.43
diff -p -u -r1.43 Makefile.am
--- tests/Makefile.am   8 Nov 2006 20:28:57 -0000       1.43
+++ tests/Makefile.am   2 Jan 2007 02:03:55 -0000
@@ -2,7 +2,7 @@
 
 ## Makefile for Bison testsuite.
 
-## Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software
+## Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software
 ## Foundation, Inc.
 
 ## This program is free software; you can redistribute it and/or modify
@@ -93,3 +93,7 @@ maintainer-check-valgrind: $(TESTSUITE)
 
 .PHONY: maintainer-check
 maintainer-check: maintainer-check-posix maintainer-check-valgrind 
maintainer-check-g++
+
+.PHONY: maintainer-push-check
+maintainer-push-check:
+       BISON_USE_PUSH_FOR_PULL=1 $(MAKE) $(AM_MAKEFLAGS) maintainer-check