In wherePathSolver(), defer initializing variables until they are actually

needed, in case they are not needed.  This gives a small performance increase.

FossilOrigin-Name: 6f28a9652a3f1e5354afb76314db8f33f92f5e888e336d025f34881c0a8d64ae

manifest

@@ -1,5 +1,5 @@
-C Upgrade\sthe\sTEA\sbuild\ssystem\sused\sto\sbuild\sthe\sTcl\spackage.
-D 2022-07-08T15:06:07.834
+C In\swherePathSolver(),\sdefer\sinitializing\svariables\suntil\sthey\sare\sactually\nneeded,\sin\scase\sthey\sare\snot\sneeded.\s\sThis\sgives\sa\ssmall\sperformance\sincrease.
+D 2022-07-08T16:56:47.610
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -657,7 +657,7 @@ F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
 F src/wal.c 0f34033977b2275793c4330b2ebc3fa180a1baee06591cbc8f6e0d7aaa37988d
 F src/wal.h c3aa7825bfa2fe0d85bef2db94655f99870a285778baa36307c0a16da32b226a
 F src/walker.c f890a3298418d7cba3b69b8803594fdc484ea241206a8dfa99db6dd36f8cbb3b
-F src/where.c 9a44063e60d8f42dd9dc8147b8e8dcfc315bbd13e25c395211292c36d828c869
+F src/where.c 97a92f3ab73cf09cb9a4ff34f208bfdcd8dfd9bafb588e1eb15b47f9bdbde837
 F src/whereInt.h b48ca529ffe293c18cbfa8326af18a09e39910de66fb3e96ef788c7cbf8ef3a7
 F src/wherecode.c 0b09abfcb88c61c6a6984a3e065786631ff35495e9bdf865e6b74ab0a1299c5b
 F src/whereexpr.c 55a39f42aaf982574fbf52906371a84cceed98a994422198dfd03db4fce4cc46
@@ -1979,9 +1979,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 99afb3f41b923f06211d655d46c902da13c8f7aadf2421d6e93c048f5b49e660 094b2aadd55b0bd93cab5e3172e3a3c1bea83cd312920ffc79088d4a30d2689a
-R e23b050ce97a6cc9fcd8c96574e9ef0b
-T +closed 094b2aadd55b0bd93cab5e3172e3a3c1bea83cd312920ffc79088d4a30d2689a
-U dan
-Z ebcd28726742e2f504d4057c1311108e
+P ace65da8fa947926566037762ee9ff1b7686173eb7a50c7b55c4204171228b08
+R d2d96e6b5475a09297d787991573c2b0
+U drh
+Z 21d18793c5a389d6c592bdf36ef9dca6
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-ace65da8fa947926566037762ee9ff1b7686173eb7a50c7b55c4204171228b08
+6f28a9652a3f1e5354afb76314db8f33f92f5e888e336d025f34881c0a8d64ae

src/where.c

@@ -4769,9 +4769,9 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
         LogEst nOut;                      /* Rows visited by (pFrom+pWLoop) */
         LogEst rCost;                     /* Cost of path (pFrom+pWLoop) */
         LogEst rUnsorted;                 /* Unsorted cost of (pFrom+pWLoop) */
-        i8 isOrdered = pFrom->isOrdered;  /* isOrdered for (pFrom+pWLoop) */
+        i8 isOrdered;                     /* isOrdered for (pFrom+pWLoop) */
         Bitmask maskNew;                  /* Mask of src visited by (..) */
-        Bitmask revMask = 0;              /* Mask of rev-order loops for (..) */
+        Bitmask revMask;                  /* Mask of rev-order loops for (..) */
 
         if( (pWLoop->prereq & ~pFrom->maskLoop)!=0 ) continue;
         if( (pWLoop->maskSelf & pFrom->maskLoop)!=0 ) continue;
@@ -4790,7 +4790,9 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
         rUnsorted = sqlite3LogEstAdd(rUnsorted, pFrom->rUnsorted);
         nOut = pFrom->nRow + pWLoop->nOut;
         maskNew = pFrom->maskLoop | pWLoop->maskSelf;
+        isOrdered = pFrom->isOrdered;
         if( isOrdered<0 ){
+          revMask = 0;
           isOrdered = wherePathSatisfiesOrderBy(pWInfo,
                        pWInfo->pOrderBy, pFrom, pWInfo->wctrlFlags,
                        iLoop, pWLoop, &revMask);