+2006-12-31 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ * data/push.c (yypush_parse): Set yynew = 1 at the end of a parse
+ (whether successful or failed) so that yypush_parse can be invoked
+ again to start a new parse using the same yypstate.
+ * tests/torture.at (AT_DATA_STACK_TORTURE): For push mode, extend to
+ check multiple yypull_parse invocations on the same yypstate. For pull
+ mode, extend to check multiple yyparse invocations.
+ (Exploding the Stack Size with Alloca): Extend to try with
+ %push-pull-parser.
+ (Exploding the Stack Size with Malloc): Likewise.
+
+ * tests/calc.at (Simple LALR Calculator): Don't specify
+ %skeleton "push.c" since %push-pull-parser implies that now.
+ * tests/headers.at (export YYLTYPE): Don't check for the push
+ declarations. Otherwise, this test case can't be used to see if push
+ mode can truly emulate pull mode.
+ * tests/input.at (Torturing the Scanner): Likewise.
+ * tests/local.at (AT_YACC_OR_PUSH_IF, AT_PUSH_IF): Remove.
+ (AT_YYERROR_SEES_LOC_IF): Rather than AT_YACC_OR_PUSH_IF, use
+ AT_YACC_IF, which now includes the case of push mode since %skeleton
+ need not be used for push mode. This will be more intuitive once
+ push.c is renamed to yacc.c.
+
+2006-12-31 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ For push mode, convert yyparse from a macro to a function, invoke yylex
+ instead of passing a yylexp argument to yypull_parse, and don't
+ generate yypull_parse or yyparse unless %push-pull-parser is declared.
+ Discussed starting at
+ <http://lists.gnu.org/archive/html/bison-patches/2006-12/msg00163.html>.
+ * data/bison.m4 (b4_pull_if): New.
+ * data/c.m4 (b4_identification): Define YYPULL similar to YYPUSH.
+ * data/push.c: Improve M4 quoting a little.
+ (b4_generate_macro_args, b4_parenthesize): Remove.
+ (yyparse): If there's a b4_prefix, #define this to b4_prefix[parse]
+ any time a pull parser is requested.
+ Don't #define this as a wrapper around yypull_parse. Instead, when
+ both push and pull are requested, make it a function that does that
+ same thing.
+ (yypull_parse): If there's a b4_prefix, #define this to
+ b4_prefix[pull_parse] when both push and pull are requested.
+ Don't define this as a function unless both push and pull are
+ requested.
+ Remove the yylexp argument and hard-code yylex invocation instead.
+ * etc/bench.pl.in (bench_grammar): Use %push-pull-parser instead of
+ %push-parser.
+ * src/getargs.c (pull_parser): New global initialized to true.
+ * getargs.h (pull_parser): extern it.
+ * src/output.c (prepare): Insert pull_flag muscle.
+ * src/parse-gram.y (PERCENT_PUSH_PULL_PARSER): New token.
+ (prologue_declaration): Set both push_parser and pull_parser = true for
+ %push-pull-parser. Set push_parser = true and pull_parser = false for
+ %push-parser.
+ * src/scan-gram.l: Don't accept %push_parser as an alternative to
+ %push-parser since there's no backward-compatibility concern here.
+ Scan %push-pull-parser.
+ * tests/calc.at (Simple LALR(1) Calculator): Use %push-pull-parser
+ instead of %push-parser.
+ * tests/headers.at (export YYLTYPE): Make yylex static, and don't
+ prototype it in the module that calls yyparse.
+ * tests/input.at (Torturing the Scanner): Likewise.
+ * tests/local.at (AT_PUSH_IF): Check for %push-pull-parser as well.
+
+2006-12-26 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ Update etc/bench.pl. Optimize push mode a little (the yyn change
+ deserves most of the credit).
+ * Makefile.am (SUBDIRS): Add etc subdirectory.
+ * configure.ac (AC_CONFIG_FILES): Add etc/bench.pl and etc/Makefile.
+ * data/push.c (b4_declare_parser_state_variables): Move yyn, yyresult,
+ yytoken, yyval, and yyloc declarations to...
+ (yyparse or yypush_parse): ... here to improve performance. For
+ yypush_parse invocations after the first, be sure to assign yyn its old
+ value again.
+ (yypstate_new): Don't bother initializing the yyresult field since the
+ initial value isn't used.
+ (yyn, yyresult, yytoken, yyval, yyloc): For each NAME in this list,
+ remove the #define that, in push mode, set it to yyps->NAME.
+ * etc/Makefile.am: New.
+ * etc/bench.pl: Remove and build it instead from...
+ * etc/bench.pl.in: ... this new file. Use @abs_top_builddir@ to invoke
+ "tests/bison" from the build directory by default rather than just
+ invoking "bison" from $PATH.
+ (calc_grammar): Update push parser code: don't declare yylval globally,
+ don't define yyparse_wrapper, and don't #define yyparse.
+ (bench_grammar): Update to check all working combinations of yacc.c,
+ push.c, impure, pure, pull, and push.
+
+2006-12-25 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ For push mode, add pull wrappers around yypush_parse.
+ * data/push.c: (b4_generate_macro_args, b4_parenthesize): New macros.
+ (yypull_parse): New function wrapping yypush_parse.
+ (yyparse): New #define wrapping yypull_parse.
+ * tests/calc.at (_AT_DATA_CALC_Y): Call yyparse even when %push-parser
+ is declared.
+ * tests/headers.at (export YYLTYPE): Make yylex global. For push mode,
+ prototype yylex in the module that calls yyparse, and don't prototype
+ yyparse there. Otherwise, the yyparse expansion won't compile.
+ * tests/input.at (Torturing the Scanner): Likewise.
+
+2006-12-25 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ Enable push parsers to operate in impure mode. Thus, %push-parser no
+ longer implies %pure-parser. The point of this change is to move
+ towards being able to test the push parser code by running the entire
+ test suite as if %push-parser had been declared.
+ * data/push.c (yypush_parse): For impure mode, remove the
+ yypushed_char, yypushed_val, and yypushed_loc arguments.
+ Instead, declare these as local variables initialized to the global
+ yychar, yylval, and yylloc.
+ For the first yypush_parse invocation only, restore the initial values
+ of these global variables when it's time to read a token since they
+ have been overwritten.
+ * src/parse-gram.y (prologue_declaration): Don't set pure_parser for
+ %push-parser.
+ * tests/calc.at (Simple LALR(1) Calculator): Always declare
+ %pure-parser along with %push-parser since this test case was designed
+ for pure push parsers.
+ * tests/local.at (AT_PURE_OR_PUSH_IF): Remove unused.
+ (AT_YACC_OR_PUSH_IF): New.
+ (AT_YYERROR_SEES_LOC_IF): Fix enough that the test suite passes, but
+ add a note that it's still wrong for some cases (as it has been for a
+ while).
+ (AT_PURE_LEX_IF): Use AT_PURE_IF instead of AT_PURE_OR_PUSH_IF since
+ %push-parser no longer implies %pure-parser.
+
+2006-12-20 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ Remove some unnecessary differences between the pull parser code and
+ the push parser code. This patch enables yynerrs in push mode.
+ * data/push.c: Reformat M4 a little.
+ (b4_yyerror_range): Remove and convert all uses to just yyerror_range.
+ (b4_declare_scanner_communication_variables): Don't omit yynerrs just
+ because push mode is on. Instead, if pure mode is on, move yynerrs
+ to...
+ (b4_declare_parser_state_variables): ... here.
+ (yynerrs, yyerror_range): For push mode, #define each NAME in this list
+ to yyps->NAME so it can be used in yypush_parse.
+ (yypush_parse): Don't omit uses of yynerrs in push mode.
+
+2006-12-20 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ Fix bug such that the first pushed token's value and location are
+ sometimes overwritten (sometimes by %initial-action) before being used.
+ * data/push.c (yypush_parse): Rename arguments yynchar, yynlval, and
+ yynlloc to yypushed_char, yypushed_val, and yypushed_loc for clarity.
+ For the first yypush_parse invocation, initialize yychar to YYEMPTY to
+ more closely mimic the pull parser logic.
+ Don't copy the pushed token to yychar, yylval, and yylloc until it's
+ time to read a token, which is after any initialization of yylval and
+ yylloc.
+ (gottoken): Rename label to...
+ (yyread_pushed_token): ... for clarity and to avoid infringing on the
+ user namespace.
+
2006-12-20 Joel E. Denny <jdenny@ces.clemson.edu>
Rearrange initialization of the parser state variables so that the