New enhancements to .wheretrace. The 0x20000 flag shows the WHERE clause

before and after coding each loop.  The 0x800 flag shows status at the start
and at the end of each loop.  An extra "C" tag is shown on coded terms.

FossilOrigin-Name: 59cc46e5a6d8dbb030f27716ad5446ecccf81cf0cfff95338b9133777f2059e7

manifest

@@ -1,5 +1,5 @@
-C Expose\ssome\sof\sthe\sWhere\sdata\sstructure\sdebug\sprinting\sroutines\sto\sthe\nentire\sWHERE-clause\sprocessing\smodule.
-D 2019-12-28T13:39:47.110
+C New\senhancements\sto\s.wheretrace.\s\sThe\s0x20000\sflag\sshows\sthe\sWHERE\sclause\nbefore\sand\safter\scoding\seach\sloop.\s\sThe\s0x800\sflag\sshows\sstatus\sat\sthe\sstart\nand\sat\sthe\send\sof\seach\sloop.\s\sAn\sextra\s"C"\stag\sis\sshown\son\scoded\sterms.
+D 2019-12-28T14:07:22.649
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -614,9 +614,9 @@ F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
 F src/wal.c 15a2845769f51ba132f9cf0b2c7a6887a91fc8437892dbcce9fcdc68b66d60a1
 F src/wal.h 606292549f5a7be50b6227bd685fa76e3a4affad71bb8ac5ce4cb5c79f6a176a
 F src/walker.c a137468bf36c92e64d2275caa80c83902e3a0fc59273591b96c6416d3253d05d
-F src/where.c d1d79673b64278bbdefe790c70cb01ee607f79c48163febdf8dee86f6a7e715e
+F src/where.c 97f19d664256aaf86e4aac1323992c6fda5deb44ed35320539fdb3faa31307b1
 F src/whereInt.h de1b77e416ad5a7cc60a71fc1317484f8d83ca1e52b805dc8c978785a92eeded
-F src/wherecode.c d42d3e0fe93786621b84dec8065e1dc6b324d7c5934df52f141555843b6aef4e
+F src/wherecode.c d074abccfbd4ef2becc34aea640d326ff76709c5867c2b049c719a4ce5b74c06
 F src/whereexpr.c 4b34be1434183e7bb8a05d4bf42bd53ea53021b0b060936fbd12062b4ff6b396
 F src/window.c 87795bb8293179cb8a92529264d49bd66b5bcad5e91cfc17dd8d3e66a2a77f88
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
@@ -1853,7 +1853,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 52ea0672d7494346c636cd7b05ca42161eb3b07d9378fa9959be9a11de87dbbb
-R 36aa1965ca07c18187e2cc17b34e3feb
+P 85e76887761b5d7e290fb2bac7f9121648f79d67fdd92f624d81632f28620518
+R 1054236a3bfbc2d93687a4e1f244d884
 U drh
-Z 9b3b04de4e9f091e2c9e4bbb9028222c
+Z 90307d93afa9b9f29e276d59812ee8ca

manifest.uuid

@@ -1 +1 @@
-85e76887761b5d7e290fb2bac7f9121648f79d67fdd92f624d81632f28620518
+59cc46e5a6d8dbb030f27716ad5446ecccf81cf0cfff95338b9133777f2059e7

src/where.c

@@ -1735,12 +1735,13 @@ void sqlite3WhereTermPrint(WhereTerm *pTerm, int iTerm){
   if( pTerm==0 ){
     sqlite3DebugPrintf("TERM-%-3d NULL\n", iTerm);
   }else{
-    char zType[4];
+    char zType[8];
     char zLeft[50];
-    memcpy(zType, "...", 4);
+    memcpy(zType, "....", 5);
     if( pTerm->wtFlags & TERM_VIRTUAL ) zType[0] = 'V';
     if( pTerm->eOperator & WO_EQUIV  ) zType[1] = 'E';
     if( ExprHasProperty(pTerm->pExpr, EP_FromJoin) ) zType[2] = 'L';
+    if( pTerm->wtFlags & TERM_CODED  ) zType[3] = 'C';
     if( pTerm->eOperator & WO_SINGLE ){
       sqlite3_snprintf(sizeof(zLeft),zLeft,"left={%d:%d}",
                        pTerm->leftCursor, pTerm->u.leftColumn);
@@ -1751,12 +1752,13 @@ void sqlite3WhereTermPrint(WhereTerm *pTerm, int iTerm){
       sqlite3_snprintf(sizeof(zLeft),zLeft,"left=%d", pTerm->leftCursor);
     }
     sqlite3DebugPrintf(
-       "TERM-%-3d %p %s %-12s prob=%-3d op=%03x wtFlags=%04x",
-       iTerm, pTerm, zType, zLeft, pTerm->truthProb,
-       pTerm->eOperator, pTerm->wtFlags);
+       "TERM-%-3d %p %s %-12s op=%03x wtFlags=%04x",
+       iTerm, pTerm, zType, zLeft, pTerm->eOperator, pTerm->wtFlags);
+    /* The 0x10000 .wheretrace flag causes extra information to be
+    ** shown about each Term */
     if( sqlite3WhereTrace & 0x10000 ){
-      sqlite3DebugPrintf(" prereq=%llx,%llx",
-        (u64)pTerm->prereqAll, (u64)pTerm->prereqRight);
+      sqlite3DebugPrintf(" prob=%-3d prereq=%llx,%llx",
+        pTerm->truthProb, (u64)pTerm->prereqAll, (u64)pTerm->prereqRight);
     }
     if( pTerm->iField ){
       sqlite3DebugPrintf(" iField=%d", pTerm->iField);

src/wherecode.c

@@ -1284,6 +1284,17 @@ Bitmask sqlite3WhereCodeOneLoopStart(
   pLevel->notReady = notReady & ~sqlite3WhereGetMask(&pWInfo->sMaskSet, iCur);
   bRev = (pWInfo->revMask>>iLevel)&1;
   VdbeModuleComment((v, "Begin WHERE-loop%d: %s",iLevel,pTabItem->pTab->zName));
+#if WHERETRACE_ENABLED /* 0x20800 */
+  if( sqlite3WhereTrace & 0x800 ){
+    sqlite3DebugPrintf("Coding level %d:  notReady=%llx\n",
+       iLevel, (u64)notReady);
+    sqlite3WhereLoopPrint(pLoop, pWC);
+  }
+  if( sqlite3WhereTrace & 0x20000 ){
+    sqlite3DebugPrintf("Complete WHERE clause before coding:\n");
+    sqlite3WhereClausePrint(pWC);
+  }
+#endif
 
   /* Create labels for the "break" and "continue" instructions
   ** for the current loop.  Jump to addrBrk to break out of a loop.
@@ -2339,6 +2350,10 @@ Bitmask sqlite3WhereCodeOneLoopStart(
         VdbeNoopComment((v, "WhereTerm[%d] (%p) priority=%d",
                          pWC->nTerm-j, pTerm, iLoop));
       }
+      if( sqlite3WhereTrace & 0x800 ){
+        sqlite3DebugPrintf("Coding auxiliary constraint:\n");
+        sqlite3WhereTermPrint(pTerm, pWC->nTerm-j);
+      }
 #endif
       sqlite3ExprIfFalse(pParse, pE, addrCont, SQLITE_JUMPIFNULL);
       if( skipLikeAddr ) sqlite3VdbeJumpHere(v, skipLikeAddr);
@@ -2365,6 +2380,12 @@ Bitmask sqlite3WhereCodeOneLoopStart(
     if( pLevel->iLeftJoin ) continue;
     pE = pTerm->pExpr;
     assert( !ExprHasProperty(pE, EP_FromJoin) );
+#ifdef WHERETRACE_ENABLED /* 0x800 */
+    if( sqlite3WhereTrace & 0x800 ){
+      sqlite3DebugPrintf("Coding transitive constraint:\n");
+      sqlite3WhereTermPrint(pTerm, pWC->nTerm-j);
+    }
+#endif
     assert( (pTerm->prereqRight & pLevel->notReady)!=0 );
     pAlt = sqlite3WhereFindTerm(pWC, iCur, pTerm->u.leftColumn, notReady,
                     WO_EQ|WO_IN|WO_IS, 0);
@@ -2406,5 +2427,15 @@ Bitmask sqlite3WhereCodeOneLoopStart(
     }
   }
 
+#if WHERETRACE_ENABLED /* 0x20800 */
+  if( sqlite3WhereTrace & 0x20000 ){
+    sqlite3DebugPrintf("Complete WHERE clause after coding level %d:\n",iLevel);
+    sqlite3WhereClausePrint(pWC);
+  }
+  if( sqlite3WhereTrace & 0x800 ){
+    sqlite3DebugPrintf("End Coding level %d:  notReady=%llx\n",
+       iLevel, (u64)pLevel->notReady);
+  }
+#endif
   return pLevel->notReady;
 }