Enhancements to lemon to generate more compact action tables and to avoid

making array bounds tests that can never fail on action table calculations.

FossilOrigin-Name: 27d8e684db4651155c4bcb8bb44bf1c692b8c48b

diff --git a/manifest b/manifest
index 47cd8d0ac18ec3252299bec6b400f60bc56730e4..2bfb13008376d9be8edf3f2bb45abbbaffe5a9ba 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,8 +1,8 @@
 -----BEGIN PGP SIGNED MESSAGE-----
 Hash: SHA1
 
-C Force\sall\sqsort()\scalls\sin\smkkeywordhash.c\sto\sbe\sstable\sso\sthat\swe\sget\npredictable\sresults\son\sdifferent\splatforms.
-D 2009-11-03T13:08:17
+C Enhancements\sto\slemon\sto\sgenerate\smore\scompact\saction\stables\sand\sto\savoid\nmaking\sarray\sbounds\stests\sthat\scan\snever\sfail\son\saction\stable\scalculations.
+D 2009-11-03T19:18:32
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in a77dfde96ad86aafd3f71651a4333a104debe86a
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -128,7 +128,7 @@ F src/hwtime.h 4a1d45f4cae1f402ea19686acf24acf4f0cb53cb
 F src/insert.c 2fe2ef7bd03d6e0120e4525727c4ae7de5a2d571
 F src/journal.c e00df0c0da8413ab6e1bb7d7cab5665d4a9000d0
 F src/legacy.c 303b4ffcf1ae652fcf5ef635846c563c254564f6
-F src/lempar.c 0c4d1ab0a5ef2b0381eb81a732c54f68f27a574d
+F src/lempar.c 7f026423f4d71d989e719a743f98a1cbd4e6d99e
 F src/loadext.c 0e88a335665db0b2fb4cece3e49dcb65d832635a
 F src/main.c 5e12af46a6e6149b755830f9c035be6eb77995a6
 F src/malloc.c 685561d2f1602042e349aea5d7a88c3f10a63454
@@ -743,8 +743,8 @@ F tool/diffdb.c 7524b1b5df217c20cd0431f6789851a4e0cb191b
 F tool/fragck.tcl 5265a95126abcf6ab357f7efa544787e5963f439
 F tool/genfkey.README cf68fddd4643bbe3ff8e31b8b6d8b0a1b85e20f4
 F tool/genfkey.test 4196a8928b78f51d54ef58e99e99401ab2f0a7e5
-F tool/lemon.c ee5e39ce2b344ce7c81306b27a59da7698114a2d
-F tool/lempar.c 2ed70b3fc896a47e07fedfe543324f008f53d223
+F tool/lemon.c 3088e4dec7f93c6b0925cf5bac04c8b7c8688835
+F tool/lempar.c 01ca97f87610d1dac6d8cd96ab109ab1130e76dc
 F tool/mkkeywordhash.c 9216336085e7a7c226a35c0bd780239968f8304f
 F tool/mkopts.tcl 66ac10d240cc6e86abd37dc908d50382f84ff46e
 F tool/mkspeedsql.tcl a1a334d288f7adfe6e996f2e712becf076745c97
@@ -764,14 +764,14 @@ F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P d66a0f31ebcc56e6f0f462b3db6aab54f7fab816
-R 91e31635600cb3800baa14d4687e1d08
+P 3b02df27ab63936226a90098d88535ed19c2b782
+R 9657839e8a1b2321f27513cd9ab14412
 U drh
-Z 0bb2002d9c9d8d6a6987522657519773
+Z 79535e58caedc3efe5879d698faec6dd
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.6 (GNU/Linux)
 
-iD8DBQFK8CtFoxKgR168RlERAvt+AJkBQI2LJH6CUrPXrZkZDQd5FHmWKwCeNWmo
-X0wFI2+tf0Wum9Vwm5FmTGU=
-=YTMU
+iD8DBQFK8IILoxKgR168RlERAhAJAJ9pB6KdOuaqs+7SONUxYOVTE6z/WwCfZnDD
+8HkIYKOVL/iazNE6Eoivw5I=
+=rFC0
 -----END PGP SIGNATURE-----

diff --git a/manifest.uuid b/manifest.uuid
index e261fd0d44b383b855a2c9533e46c57aa8d74400..7b80eb5b4fa285420098031e73a107423a6d5ef5 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-3b02df27ab63936226a90098d88535ed19c2b782
\ No newline at end of file
+27d8e684db4651155c4bcb8bb44bf1c692b8c48b
\ No newline at end of file

diff --git a/src/lempar.c b/src/lempar.c
index 8439bd71c7cd7703b11caf9ce8d24d1227f4a14b..fb52490e4c14cb74b6ccfadbd44f46c70893760e 100644 (file)
--- a/src/lempar.c
+++ b/src/lempar.c
@@ -131,7 +131,6 @@ static const YYMINORTYPE yyzerominor = { 0 };
 **  yy_default[]       Default action for each state.
 */
 %%
-#define YY_SZ_ACTTAB (int)(sizeof(yy_action)/sizeof(yy_action[0]))
 
 /* The next table maps tokens into fallback tokens.  If a construct
 ** like the following:
@@ -396,14 +395,13 @@ static int yy_find_shift_action(
   int i;
   int stateno = pParser->yystack[pParser->yyidx].stateno;
  
-  if( stateno>YY_SHIFT_MAX || (i = yy_shift_ofst[stateno])==YY_SHIFT_USE_DFLT ){
+  if( stateno>YY_SHIFT_COUNT
+   || (i = yy_shift_ofst[stateno])==YY_SHIFT_USE_DFLT ){
     return yy_default[stateno];
   }
   assert( iLookAhead!=YYNOCODE );
   i += iLookAhead;
-  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
-    /* The user of ";" instead of "\000" as a statement terminator in SQLite
-    ** means that we always have a look-ahead token. */
+  if( i<0 || i>=YY_ACTTAB_COUNT || yy_lookahead[i]!=iLookAhead ){
     if( iLookAhead>0 ){
 #ifdef YYFALLBACK
       YYCODETYPE iFallback;            /* Fallback token */
@@ -421,7 +419,15 @@ static int yy_find_shift_action(
 #ifdef YYWILDCARD
       {
         int j = i - iLookAhead + YYWILDCARD;
-        if( j>=0 && j<YY_SZ_ACTTAB && yy_lookahead[j]==YYWILDCARD ){
+        if( 
+#if YY_SHIFT_MIN+YYWILDCARD<0
+          j>=0 &&
+#endif
+#if YY_SHIFT_MAX+YYWILDCARD>=YY_ACTTAB_COUNT
+          j<YY_ACTTAB_COUNT &&
+#endif
+          yy_lookahead[j]==YYWILDCARD
+        ){
 #ifndef NDEBUG
           if( yyTraceFILE ){
             fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
@@ -453,22 +459,22 @@ static int yy_find_reduce_action(
 ){
   int i;
 #ifdef YYERRORSYMBOL
-  if( stateno>YY_REDUCE_MAX ){
+  if( stateno>YY_REDUCE_COUNT ){
     return yy_default[stateno];
   }
 #else
-  assert( stateno<=YY_REDUCE_MAX );
+  assert( stateno<=YY_REDUCE_COUNT );
 #endif
   i = yy_reduce_ofst[stateno];
   assert( i!=YY_REDUCE_USE_DFLT );
   assert( iLookAhead!=YYNOCODE );
   i += iLookAhead;
 #ifdef YYERRORSYMBOL
-  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
+  if( i<0 || i>=YY_ACTTAB_COUNT || yy_lookahead[i]!=iLookAhead ){
     return yy_default[stateno];
   }
 #else
-  assert( i>=0 && i<YY_SZ_ACTTAB );
+  assert( i>=0 && i<YY_ACTTAB_COUNT );
   assert( yy_lookahead[i]==iLookAhead );
 #endif
   return yy_action[i];

diff --git a/tool/lemon.c b/tool/lemon.c
index bde65362bc9693195f7ee60d5eab4b0023ed344f..75c29fc3e596cd865288e06a15f0317882e0b6fb 100644 (file)
--- a/tool/lemon.c
+++ b/tool/lemon.c
@@ -520,21 +520,9 @@ int acttab_insert(acttab *p){
   **
   ** i is the index in p->aAction[] where p->mnLookahead is inserted.
   */
-  for(i=0; i<p->nAction+p->mnLookahead; i++){
-    if( p->aAction[i].lookahead<0 ){
-      for(j=0; j<p->nLookahead; j++){
-        k = p->aLookahead[j].lookahead - p->mnLookahead + i;
-        if( k<0 ) break;
-        if( p->aAction[k].lookahead>=0 ) break;
-      }
-      if( j<p->nLookahead ) continue;
-      for(j=0; j<p->nAction; j++){
-        if( p->aAction[j].lookahead==j+p->mnLookahead-i ) break;
-      }
-      if( j==p->nAction ){
-        break;  /* Fits in empty slots */
-      }
-    }else if( p->aAction[i].lookahead==p->mnLookahead ){
+  for(i=p->nAction-1; i>=0; i--){
+    /* First look for an existing action table entry that can be reused */
+    if( p->aAction[i].lookahead==p->mnLookahead ){
       if( p->aAction[i].action!=p->mnAction ) continue;
       for(j=0; j<p->nLookahead; j++){
         k = p->aLookahead[j].lookahead - p->mnLookahead + i;
@@ -553,6 +541,25 @@ int acttab_insert(acttab *p){
       }
     }
   }
+  if( i<0 ){
+    /* If no reusable entry is found, look for an empty slot */
+    for(i=0; i<p->nAction; i++){
+      if( p->aAction[i].lookahead<0 ){
+        for(j=0; j<p->nLookahead; j++){
+          k = p->aLookahead[j].lookahead - p->mnLookahead + i;
+          if( k<0 ) break;
+          if( p->aAction[k].lookahead>=0 ) break;
+        }
+        if( j<p->nLookahead ) continue;
+        for(j=0; j<p->nAction; j++){
+          if( p->aAction[j].lookahead==j+p->mnLookahead-i ) break;
+        }
+        if( j==p->nAction ){
+          break;  /* Fits in empty slots */
+        }
+      }
+    }
+  }
   /* Insert transaction set at index i. */
   for(j=0; j<p->nLookahead; j++){
     k = p->aLookahead[j].lookahead - p->mnLookahead + i;
@@ -3568,7 +3575,7 @@ int mhflag;     /* Output in makeheaders format if true */
   struct action *ap;
   struct rule *rp;
   struct acttab *pActtab;
-  int i, j, n;
+  int i, j, k, n;
   char *name;
   int mnTknOfst, mxTknOfst;
   int mnNtOfst, mxNtOfst;
@@ -3727,8 +3734,9 @@ int mhflag;     /* Output in makeheaders format if true */
   free(ax);
 
   /* Output the yy_action table */
-  fprintf(out,"static const YYACTIONTYPE yy_action[] = {\n"); lineno++;
   n = acttab_size(pActtab);
+  fprintf(out,"#define YY_ACTTAB_COUNT (%d)\n", n); lineno++;
+  fprintf(out,"static const YYACTIONTYPE yy_action[] = {\n"); lineno++;
   for(i=j=0; i<n; i++){
     int action = acttab_yyaction(pActtab, i);
     if( action<0 ) action = lemp->nstate + lemp->nrule + 2;
@@ -3763,7 +3771,9 @@ int mhflag;     /* Output in makeheaders format if true */
   fprintf(out, "#define YY_SHIFT_USE_DFLT (%d)\n", mnTknOfst-1); lineno++;
   n = lemp->nstate;
   while( n>0 && lemp->sorted[n-1]->iTknOfst==NO_OFFSET ) n--;
-  fprintf(out, "#define YY_SHIFT_MAX %d\n", n-1); lineno++;
+  fprintf(out, "#define YY_SHIFT_COUNT (%d)\n", n-1); lineno++;
+  fprintf(out, "#define YY_SHIFT_MIN   (%d)\n", mnTknOfst); lineno++;
+  fprintf(out, "#define YY_SHIFT_MAX   (%d)\n", mxTknOfst); lineno++;
   fprintf(out, "static const %s yy_shift_ofst[] = {\n", 
           minimum_size_type(mnTknOfst-1, mxTknOfst)); lineno++;
   for(i=j=0; i<n; i++){
@@ -3786,7 +3796,9 @@ int mhflag;     /* Output in makeheaders format if true */
   fprintf(out, "#define YY_REDUCE_USE_DFLT (%d)\n", mnNtOfst-1); lineno++;
   n = lemp->nstate;
   while( n>0 && lemp->sorted[n-1]->iNtOfst==NO_OFFSET ) n--;
-  fprintf(out, "#define YY_REDUCE_MAX %d\n", n-1); lineno++;
+  fprintf(out, "#define YY_REDUCE_COUNT (%d)\n", n-1); lineno++;
+  fprintf(out, "#define YY_REDUCE_MIN   (%d)\n", mnNtOfst); lineno++;
+  fprintf(out, "#define YY_REDUCE_MAX   (%d)\n", mxNtOfst); lineno++;
   fprintf(out, "static const %s yy_reduce_ofst[] = {\n", 
           minimum_size_type(mnNtOfst-1, mxNtOfst)); lineno++;
   for(i=j=0; i<n; i++){

diff --git a/tool/lempar.c b/tool/lempar.c
index 774b875e21dab65e0e4c65a19e5f7b09e2bd2d2b..fe56d2dc1661eb9c2468ab9b0c763238e79f6252 100644 (file)
--- a/tool/lempar.c
+++ b/tool/lempar.c
@@ -125,7 +125,6 @@ static const YYMINORTYPE yyzerominor = { 0 };
 **  yy_default[]       Default action for each state.
 */
 %%
-#define YY_SZ_ACTTAB (int)(sizeof(yy_action)/sizeof(yy_action[0]))
 
 /* The next table maps tokens into fallback tokens.  If a construct
 ** like the following:
@@ -386,12 +385,13 @@ static int yy_find_shift_action(
   int i;
   int stateno = pParser->yystack[pParser->yyidx].stateno;
  
-  if( stateno>YY_SHIFT_MAX || (i = yy_shift_ofst[stateno])==YY_SHIFT_USE_DFLT ){
+  if( stateno>YY_SHIFT_COUNT
+   || (i = yy_shift_ofst[stateno])==YY_SHIFT_USE_DFLT ){
     return yy_default[stateno];
   }
   assert( iLookAhead!=YYNOCODE );
   i += iLookAhead;
-  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
+  if( i<0 || i>=YY_ACTTAB_COUNT || yy_lookahead[i]!=iLookAhead ){
     if( iLookAhead>0 ){
 #ifdef YYFALLBACK
       YYCODETYPE iFallback;            /* Fallback token */
@@ -409,7 +409,15 @@ static int yy_find_shift_action(
 #ifdef YYWILDCARD
       {
         int j = i - iLookAhead + YYWILDCARD;
-        if( j>=0 && j<YY_SZ_ACTTAB && yy_lookahead[j]==YYWILDCARD ){
+        if( 
+#if YY_SHIFT_MIN+YYWILDCARD<0
+          j>=0 &&
+#endif
+#if YY_SHIFT_MAX+YYWILDCARD>=YY_ACTTAB_COUNT
+          j<YY_ACTTAB_COUNT &&
+#endif
+          yy_lookahead[j]==YYWILDCARD
+        ){
 #ifndef NDEBUG
           if( yyTraceFILE ){
             fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
@@ -441,22 +449,22 @@ static int yy_find_reduce_action(
 ){
   int i;
 #ifdef YYERRORSYMBOL
-  if( stateno>YY_REDUCE_MAX ){
+  if( stateno>YY_REDUCE_COUNT ){
     return yy_default[stateno];
   }
 #else
-  assert( stateno<=YY_REDUCE_MAX );
+  assert( stateno<=YY_REDUCE_COUNT );
 #endif
   i = yy_reduce_ofst[stateno];
   assert( i!=YY_REDUCE_USE_DFLT );
   assert( iLookAhead!=YYNOCODE );
   i += iLookAhead;
 #ifdef YYERRORSYMBOL
-  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
+  if( i<0 || i>=YY_ACTTAB_COUNT || yy_lookahead[i]!=iLookAhead ){
     return yy_default[stateno];
   }
 #else
-  assert( i>=0 && i<YY_SZ_ACTTAB );
+  assert( i>=0 && i<YY_ACTTAB_COUNT );
   assert( yy_lookahead[i]==iLookAhead );
 #endif
   return yy_action[i];