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Encapsulate the push parser state variables into an M4 macro so the

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push skeleton doesn't have to list them again for pull mode's yyparse.
For push mode, remove yypush_parse's local equivalents of these
variables to eliminate unnecessary copying between the two sets at
run-time.  This patch also fixes at least a bug related to multiple
%initial-action invocations in push mode.
* data/push.c (b4_declare_parser_variables): Rename to...
(b4_declare_scanner_communication_variables): ... this for clarity and
update both uses.
(b4_declare_yyparse_variables): Remove and move its contents to the one
spot where it was invoked.
(b4_declare_parser_state_variables): New macro containing the parser
state variables required by push mode.
(struct yypstate): Replace all fields but yynew with
b4_declare_parser_state_variables.
(yystate, yyn, yyresult, yyerrstatus, yytoken, yyss, yyssp, yyvs,
yyvsp, yyls, yylsp, yystacksize, yyval, yyloc): For push mode, #define
each NAME in this list to yyps->NAME so it can be used in yypush_parse.
(yyparse or yypush_parse): For yyparse in pull mode, replace local
parser state variable declarations with
b4_declare_parser_state_variables.
Don't initialize parser state variables when calling yypush_parse since
yypstate_new already does that.
Invoke the user's initial action only upon the first yypush_parse
invocation.
Remove all code that copies between the local parser state variables
and the yypstate.
This commit is contained in:
Joel E. Denny
2006-12-20 00:59:18 +00:00
parent 2d212f8ca6
commit bb010fe51a
2 changed files with 93 additions and 119 deletions
Download Patch File Download Diff File Expand all files Collapse all files

182
data/push.c
View File

@@ -981,11 +981,11 @@ enum { YYPUSH_MORE = 4 };
#endif /* ! YYPARSE_PARAM */])[
]m4_divert_push([KILL])# ======================== M4 code.
# b4_declare_parser_variables
# ---------------------------
# b4_declare_scanner_communication_variables
# ------------------------------------------
# Declare the variables that are global, or local to YYPARSE if
# pure-parser.
m4_define([b4_declare_parser_variables],
m4_define([b4_declare_scanner_communication_variables],
[/* The lookahead symbol. */
int yychar;
@@ -1002,19 +1002,19 @@ YYLTYPE yylloc;])
m4_define([b4_yyssa],b4_push_if([yyps->yyssa],[yyssa]))
m4_define([b4_yyerror_range],b4_push_if([yyps->yyerror_range],[yyerror_range]))
# b4_declare_yyparse_variables
# ----------------------------
# Declare all the variables that are needed local to YYPARSE
m4_define([b4_declare_yyparse_variables],
[[struct yypstate
{
# b4_declare_parser_state_variables
# ---------------------------------
# Declare all the variables that are needed to maintain the parser state
# between calls to yypush_parse.
m4_define([b4_declare_parser_state_variables],
[[
int yystate;
int yyn;
int yyresult;
/* Number of tokens to shift before error messages enabled. */
int yyerrstatus;
/* Look-ahead token as an internal (translated) token number. */
int yytoken;
int yytoken]b4_push_if([], [[ = 0]])[;
/* Three stacks and their tools:
`yyss': related to states,
@@ -1026,26 +1026,37 @@ m4_define([b4_declare_yyparse_variables],
/* The state stack. */
yytype_int16 yyssa[YYINITDEPTH];
yytype_int16 *yyss;
yytype_int16 *yyss]b4_push_if([], [[ = yyssa]])[;
yytype_int16 *yyssp;
/* The semantic value stack. */
YYSTYPE yyvsa[YYINITDEPTH];
YYSTYPE *yyvs;
YYSTYPE *yyvsp;]]b4_locations_if([[[
YYSTYPE *yyvs]b4_push_if([], [[ = yyvsa]])[;
YYSTYPE *yyvsp;]b4_locations_if([[
/* The location stack. */
YYLTYPE yylsa[YYINITDEPTH];
YYLTYPE *yyls;
YYLTYPE *yyls]b4_push_if([], [[ = yylsa]])[;
YYLTYPE *yylsp;
/* The locations where the error started and ended. */
YYLTYPE yyerror_range[2];]]])[
YYSIZE_T yystacksize;
YYLTYPE yyerror_range[2];]])[
YYSIZE_T yystacksize]b4_push_if([], [[ = YYINITDEPTH]])[;
/* The variables used to return semantic value and location from the
action routines. */
YYSTYPE yyval;
YYSTYPE yyval;]b4_locations_if([[
YYLTYPE yyloc;]])
])
m4_divert_pop([KILL])dnl# ====================== End of M4 code.
b4_pure_if([], [b4_declare_scanner_communication_variables])
b4_push_if(
[[struct yypstate
{
]b4_declare_parser_state_variables[
/* Used to determine if this is the first time this instance has
been used. */
int yynew;]b4_locations_if([YYLTYPE yyloc;])[
int yynew;
};
/* Initialize the parser data structure. */
@@ -1079,18 +1090,28 @@ m4_define([b4_declare_yyparse_variables],
{
free (yyps);
}
])
m4_divert_pop([KILL])dnl# ====================== End of M4 code.
b4_pure_if([], [b4_declare_parser_variables])
b4_push_if([b4_declare_yyparse_variables])
#define yystate yyps->yystate
#define yyn yyps->yyn
#define yyresult yyps->yyresult
#define yyerrstatus yyps->yyerrstatus
#define yytoken yyps->yytoken
#define yyss yyps->yyss
#define yyssp yyps->yyssp
#define yyvs yyps->yyvs
#define yyvsp yyps->yyvsp
]b4_locations_if([[#define yyls yyps->yyls
#define yylsp yyps->yylsp
]])[#define yystacksize yyps->yystacksize
#define yyval yyps->yyval
]b4_locations_if([[#define yyloc yyps->yyloc
]])])[
/*-------------------------.
| yyparse or yypush_parse. |
`-------------------------*/
b4_push_if([
]b4_push_if([
b4_c_function_def([yypush_parse], [int], [[yypstate *yyps], [yyps]],
[[int yynchar], [yynchar]],
[[YYSTYPE const *yynlval], [yynlval]]
@@ -1100,16 +1121,11 @@ b4_c_function_def([yypush_parse], [int], [[yypstate *yyps], [yyps]],
b4_c_function_def([yyparse], [int], [[void *YYPARSE_PARAM], [YYPARSE_PARAM]])
#else /* ! YYPARSE_PARAM */
b4_c_function_def([yyparse], [int], b4_parse_param)
#endif])
{[
]b4_pure_if([b4_declare_parser_variables])[
int yystate;
int yyn;
int yyresult;
/* Number of tokens to shift before error messages enabled. */
int yyerrstatus;
/* Lookahead token as an internal (translated) token number. */
int yytoken = 0;
#endif])[
{
]b4_pure_if([b4_declare_scanner_communication_variables])
b4_push_if([], [b4_declare_parser_state_variables])[
#if YYERROR_VERBOSE
/* Buffer for error messages, and its allocated size. */
char yymsgbuf[128];
@@ -1117,50 +1133,14 @@ b4_c_function_def([yyparse], [int], b4_parse_param)
YYSIZE_T yymsg_alloc = sizeof yymsgbuf;
#endif
/* Three stacks and their tools:
`yyss': related to states,
`yyvs': related to semantic values,
`yyls': related to locations.
Refer to the stacks thru separate pointers, to allow yyoverflow
to reallocate them elsewhere. */
/* The state stack. */
yytype_int16 yyssa[YYINITDEPTH];
yytype_int16 *yyss = yyssa;
yytype_int16 *yyssp;
/* The semantic value stack. */
YYSTYPE yyvsa[YYINITDEPTH];
YYSTYPE *yyvs = yyvsa;
YYSTYPE *yyvsp;
]b4_locations_if(
[[ /* The location stack. */
YYLTYPE yylsa[YYINITDEPTH];
YYLTYPE *yyls = yylsa;
YYLTYPE *yylsp;
/* The locations where the error started and ended. */
]b4_push_if([],[YYLTYPE yyerror_range[[2]]])[;
]])[
#define YYPOPSTACK(N) (yyvsp -= (N), yyssp -= (N)]b4_locations_if([, yylsp -= (N)])[)
YYSIZE_T yystacksize = YYINITDEPTH;
/* The variables used to return semantic value and location from the
action routines. */
YYSTYPE yyval;
]b4_locations_if([ YYLTYPE yyloc;])[
/* The number of symbols on the RHS of the reduced rule.
Keep to zero when no symbol should be popped. */
int yylen = 0;
YYDPRINTF ((stderr, "Starting parse\n"));
yystate = 0;
yyerrstatus = 0;
]b4_push_if([ yychar = yynchar;
if (yynlval)
yylval = *yynlval;
@@ -1168,6 +1148,10 @@ b4_c_function_def([yyparse], [int], b4_parse_param)
yylloc = *yynlloc;])[],[yynerrs = 0;
yychar = YYEMPTY; /* Cause a token to be read. */])[
]b4_push_if([],[[
yystate = 0;
yyerrstatus = 0;
/* Initialize stack pointers.
Waste one element of value and location stack
so that they stay on the same level as the state stack.
@@ -1176,13 +1160,18 @@ b4_c_function_def([yyparse], [int], b4_parse_param)
yyssp = yyss;
yyvsp = yyvs;
]b4_locations_if([[ yylsp = yyls;
]b4_push_if([],[
#if YYLTYPE_IS_TRIVIAL
/* Initialize the default location before parsing starts. */
yylloc.first_line = yylloc.last_line = ]b4_location_initial_line[;
yylloc.first_column = yylloc.last_column = ]b4_location_initial_column[;
#endif])[
]])
#endif]])
])
[ ]b4_push_if([
if (yyps->yynew == 0)
{
goto gottoken;
}
yyps->yynew= 0;])
m4_ifdef([b4_initial_action], [
m4_pushdef([b4_at_dollar], [m4_define([b4_at_dollar_used])yylloc])dnl
m4_pushdef([b4_dollar_dollar], [m4_define([b4_dollar_dollar_used])yylval])dnl
@@ -1194,32 +1183,7 @@ m4_ifdef([b4_dollar_dollar_used],[[ yyvsp[0] = yylval;
]])dnl
m4_ifdef([b4_at_dollar_used], [[ yylsp[0] = yylloc;
]])dnl
[ ]b4_push_if([
/* Initialize the locals to the current context. */
yystate = yyps->yystate;
yyn = yyps->yyn;
yyresult = yyps->yyresult;
yyerrstatus = yyps->yyerrstatus;
yytoken = yyps->yytoken;
yyss = yyps->yyss;
yyssp = yyps->yyssp;
yyvs = yyps->yyvs;
yyvsp = yyps->yyvsp;
]b4_locations_if([[ /* The location stack. */
yyls = yyps->yyls;
yylsp = yyps->yylsp;]])[
yystacksize = yyps->yystacksize;
yyval = yyps->yyval;
]b4_locations_if([yyloc = yyps->yyloc;])[
if (yyps->yynew == 0)
{
goto gottoken;
}
yyps->yynew= 0;])[
[
goto yysetstate;
/*------------------------------------------------------------.
@@ -1326,25 +1290,6 @@ yybackup:
]b4_push_if([
YYDPRINTF ((stderr, "Return for a new token:\n"));
yyresult = YYPUSH_MORE;
/* Initialize the locals to the current context. */
yyps->yystate = yystate;
yyps->yyn = yyn;
yyps->yyerrstatus = yyerrstatus;
yyps->yytoken = yytoken;
yyps->yyss = yyss;
yyps->yyssp = yyssp;
yyps->yyvs = yyvs;
yyps->yyvsp = yyvsp;
]b4_locations_if([[ /* The location stack. */
yyps->yyls = yyls;
yyps->yylsp = yylsp;]])[
yyps->yystacksize = yystacksize;
yyps->yyval = yyval;
]b4_locations_if([yyps->yyloc = yyloc;])[
goto yypushreturn;
gottoken:])[
YYDPRINTF ((stderr, "Reading a token: "));
@@ -1639,7 +1584,6 @@ yyreturn:
if (yymsg != yymsgbuf)
YYSTACK_FREE (yymsg);
#endif
]b4_push_if([yyps->yyresult = YYID (yyresult);])[
/* Make sure YYID is used. */
return YYID (yyresult);
]}