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-rw-r--r--tool/lempar.c133
1 files changed, 91 insertions, 42 deletions
diff --git a/tool/lempar.c b/tool/lempar.c
index da81ddd4b..9164eb0c1 100644
--- a/tool/lempar.c
+++ b/tool/lempar.c
@@ -72,14 +72,15 @@
** defined, then do no error processing.
** YYNSTATE the combined number of states.
** YYNRULE the number of rules in the grammar
+** YYNTOKEN Number of terminal symbols
** YY_MAX_SHIFT Maximum value for shift actions
** YY_MIN_SHIFTREDUCE Minimum value for shift-reduce actions
** YY_MAX_SHIFTREDUCE Maximum value for shift-reduce actions
-** YY_MIN_REDUCE Minimum value for reduce actions
-** YY_MAX_REDUCE Maximum value for reduce actions
** YY_ERROR_ACTION The yy_action[] code for syntax error
** YY_ACCEPT_ACTION The yy_action[] code for accept
** YY_NO_ACTION The yy_action[] code for no-op
+** YY_MIN_REDUCE Minimum value for reduce actions
+** YY_MAX_REDUCE Maximum value for reduce actions
*/
#ifndef INTERFACE
# define INTERFACE 1
@@ -115,9 +116,6 @@
** N between YY_MIN_SHIFTREDUCE Shift to an arbitrary state then
** and YY_MAX_SHIFTREDUCE reduce by rule N-YY_MIN_SHIFTREDUCE.
**
-** N between YY_MIN_REDUCE Reduce by rule N-YY_MIN_REDUCE
-** and YY_MAX_REDUCE
-**
** N == YY_ERROR_ACTION A syntax error has occurred.
**
** N == YY_ACCEPT_ACTION The parser accepts its input.
@@ -125,25 +123,22 @@
** N == YY_NO_ACTION No such action. Denotes unused
** slots in the yy_action[] table.
**
+** N between YY_MIN_REDUCE Reduce by rule N-YY_MIN_REDUCE
+** and YY_MAX_REDUCE
+**
** The action table is constructed as a single large table named yy_action[].
** Given state S and lookahead X, the action is computed as either:
**
** (A) N = yy_action[ yy_shift_ofst[S] + X ]
** (B) N = yy_default[S]
**
-** The (A) formula is preferred. The B formula is used instead if:
-** (1) The yy_shift_ofst[S]+X value is out of range, or
-** (2) yy_lookahead[yy_shift_ofst[S]+X] is not equal to X, or
-** (3) yy_shift_ofst[S] equal YY_SHIFT_USE_DFLT.
-** (Implementation note: YY_SHIFT_USE_DFLT is chosen so that
-** YY_SHIFT_USE_DFLT+X will be out of range for all possible lookaheads X.
-** Hence only tests (1) and (2) need to be evaluated.)
+** The (A) formula is preferred. The B formula is used instead if
+** yy_lookahead[yy_shift_ofst[S]+X] is not equal to X.
**
** The formulas above are for computing the action when the lookahead is
** a terminal symbol. If the lookahead is a non-terminal (as occurs after
** a reduce action) then the yy_reduce_ofst[] array is used in place of
-** the yy_shift_ofst[] array and YY_REDUCE_USE_DFLT is used in place of
-** YY_SHIFT_USE_DFLT.
+** the yy_shift_ofst[] array.
**
** The following are the tables generated in this section:
**
@@ -259,13 +254,13 @@ void ParseTrace(FILE *TraceFILE, char *zTracePrompt){
}
#endif /* NDEBUG */
-#ifndef NDEBUG
+#if defined(YYCOVERAGE) || !defined(NDEBUG)
/* For tracing shifts, the names of all terminals and nonterminals
** are required. The following table supplies these names */
static const char *const yyTokenName[] = {
%%
};
-#endif /* NDEBUG */
+#endif /* defined(YYCOVERAGE) || !defined(NDEBUG) */
#ifndef NDEBUG
/* For tracing reduce actions, the names of all rules are required.
@@ -461,6 +456,43 @@ int ParseStackPeak(void *p){
}
#endif
+/* This array of booleans keeps track of the parser statement
+** coverage. The element yycoverage[X][Y] is set when the parser
+** is in state X and has a lookahead token Y. In a well-tested
+** systems, every element of this matrix should end up being set.
+*/
+#if defined(YYCOVERAGE)
+static unsigned char yycoverage[YYNSTATE][YYNTOKEN];
+#endif
+
+/*
+** Write into out a description of every state/lookahead combination that
+**
+** (1) has not been used by the parser, and
+** (2) is not a syntax error.
+**
+** Return the number of missed state/lookahead combinations.
+*/
+#if defined(YYCOVERAGE)
+int ParseCoverage(FILE *out){
+ int stateno, iLookAhead, i;
+ int nMissed = 0;
+ for(stateno=0; stateno<YYNSTATE; stateno++){
+ i = yy_shift_ofst[stateno];
+ for(iLookAhead=0; iLookAhead<YYNTOKEN; iLookAhead++){
+ if( yy_lookahead[i+iLookAhead]!=iLookAhead ) continue;
+ if( yycoverage[stateno][iLookAhead]==0 ) nMissed++;
+ if( out ){
+ fprintf(out,"State %d lookahead %s %s\n", stateno,
+ yyTokenName[iLookAhead],
+ yycoverage[stateno][iLookAhead] ? "ok" : "missed");
+ }
+ }
+ }
+ return nMissed;
+}
+#endif
+
/*
** Find the appropriate action for a parser given the terminal
** look-ahead token iLookAhead.
@@ -472,13 +504,18 @@ static unsigned int yy_find_shift_action(
int i;
int stateno = pParser->yytos->stateno;
- if( stateno>=YY_MIN_REDUCE ) return stateno;
+ if( stateno>YY_MAX_SHIFT ) return stateno;
assert( stateno <= YY_SHIFT_COUNT );
+#if defined(YYCOVERAGE)
+ yycoverage[stateno][iLookAhead] = 1;
+#endif
do{
i = yy_shift_ofst[stateno];
+ assert( i>=0 && i+YYNTOKEN<=sizeof(yy_lookahead)/sizeof(yy_lookahead[0]) );
assert( iLookAhead!=YYNOCODE );
+ assert( iLookAhead < YYNTOKEN );
i += iLookAhead;
- if( i<0 || i>=YY_ACTTAB_COUNT || yy_lookahead[i]!=iLookAhead ){
+ if( yy_lookahead[i]!=iLookAhead ){
#ifdef YYFALLBACK
YYCODETYPE iFallback; /* Fallback token */
if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
@@ -541,7 +578,6 @@ static int yy_find_reduce_action(
assert( stateno<=YY_REDUCE_COUNT );
#endif
i = yy_reduce_ofst[stateno];
- assert( i!=YY_REDUCE_USE_DFLT );
assert( iLookAhead!=YYNOCODE );
i += iLookAhead;
#ifdef YYERRORSYMBOL
@@ -578,20 +614,21 @@ static void yyStackOverflow(yyParser *yypParser){
** Print tracing information for a SHIFT action
*/
#ifndef NDEBUG
-static void yyTraceShift(yyParser *yypParser, int yyNewState){
+static void yyTraceShift(yyParser *yypParser, int yyNewState, const char *zTag){
if( yyTraceFILE ){
if( yyNewState<YYNSTATE ){
- fprintf(yyTraceFILE,"%sShift '%s', go to state %d\n",
- yyTracePrompt,yyTokenName[yypParser->yytos->major],
+ fprintf(yyTraceFILE,"%s%s '%s', go to state %d\n",
+ yyTracePrompt, zTag, yyTokenName[yypParser->yytos->major],
yyNewState);
}else{
- fprintf(yyTraceFILE,"%sShift '%s'\n",
- yyTracePrompt,yyTokenName[yypParser->yytos->major]);
+ fprintf(yyTraceFILE,"%s%s '%s', pending reduce %d\n",
+ yyTracePrompt, zTag, yyTokenName[yypParser->yytos->major],
+ yyNewState - YY_MIN_REDUCE);
}
}
}
#else
-# define yyTraceShift(X,Y)
+# define yyTraceShift(X,Y,Z)
#endif
/*
@@ -633,7 +670,7 @@ static void yy_shift(
yytos->stateno = (YYACTIONTYPE)yyNewState;
yytos->major = (YYCODETYPE)yyMajor;
yytos->minor.yy0 = yyMinor;
- yyTraceShift(yypParser, yyNewState);
+ yyTraceShift(yypParser, yyNewState, "Shift");
}
/* The following table contains information about every rule that
@@ -673,8 +710,14 @@ static void yy_reduce(
#ifndef NDEBUG
if( yyTraceFILE && yyruleno<(int)(sizeof(yyRuleName)/sizeof(yyRuleName[0])) ){
yysize = yyRuleInfo[yyruleno].nrhs;
- fprintf(yyTraceFILE, "%sReduce [%s], go to state %d.\n", yyTracePrompt,
- yyRuleName[yyruleno], yymsp[yysize].stateno);
+ if( yysize ){
+ fprintf(yyTraceFILE, "%sReduce %d [%s], go to state %d.\n",
+ yyTracePrompt,
+ yyruleno, yyRuleName[yyruleno], yymsp[yysize].stateno);
+ }else{
+ fprintf(yyTraceFILE, "%sReduce %d [%s].\n",
+ yyTracePrompt, yyruleno, yyRuleName[yyruleno]);
+ }
}
#endif /* NDEBUG */
@@ -729,16 +772,11 @@ static void yy_reduce(
/* It is not possible for a REDUCE to be followed by an error */
assert( yyact!=YY_ERROR_ACTION );
- if( yyact==YY_ACCEPT_ACTION ){
- yypParser->yytos += yysize;
- yy_accept(yypParser);
- }else{
- yymsp += yysize+1;
- yypParser->yytos = yymsp;
- yymsp->stateno = (YYACTIONTYPE)yyact;
- yymsp->major = (YYCODETYPE)yygoto;
- yyTraceShift(yypParser, yyact);
- }
+ yymsp += yysize+1;
+ yypParser->yytos = yymsp;
+ yymsp->stateno = (YYACTIONTYPE)yyact;
+ yymsp->major = (YYCODETYPE)yygoto;
+ yyTraceShift(yypParser, yyact, "... then shift");
}
/*
@@ -848,20 +886,31 @@ void Parse(
#ifndef NDEBUG
if( yyTraceFILE ){
- fprintf(yyTraceFILE,"%sInput '%s'\n",yyTracePrompt,yyTokenName[yymajor]);
+ int stateno = yypParser->yytos->stateno;
+ if( stateno < YY_MIN_REDUCE ){
+ fprintf(yyTraceFILE,"%sInput '%s' in state %d\n",
+ yyTracePrompt,yyTokenName[yymajor],stateno);
+ }else{
+ fprintf(yyTraceFILE,"%sInput '%s' with pending reduce %d\n",
+ yyTracePrompt,yyTokenName[yymajor],stateno-YY_MIN_REDUCE);
+ }
}
#endif
do{
yyact = yy_find_shift_action(yypParser,(YYCODETYPE)yymajor);
- if( yyact <= YY_MAX_SHIFTREDUCE ){
+ if( yyact >= YY_MIN_REDUCE ){
+ yy_reduce(yypParser,yyact-YY_MIN_REDUCE,yymajor,yyminor);
+ }else if( yyact <= YY_MAX_SHIFTREDUCE ){
yy_shift(yypParser,yyact,yymajor,yyminor);
#ifndef YYNOERRORRECOVERY
yypParser->yyerrcnt--;
#endif
yymajor = YYNOCODE;
- }else if( yyact <= YY_MAX_REDUCE ){
- yy_reduce(yypParser,yyact-YY_MIN_REDUCE,yymajor,yyminor);
+ }else if( yyact==YY_ACCEPT_ACTION ){
+ yypParser->yytos--;
+ yy_accept(yypParser);
+ return;
}else{
assert( yyact == YY_ERROR_ACTION );
yyminorunion.yy0 = yyminor;