diff --git a/manifest b/manifest
index b258cece78..5040ebb57d 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fixes\sfor\svarious\sharmless\scompiler\swarnings.
-D 2018-07-09T22:49:01.906
+C New\sVDBE\scomments\sand\scoverage\smacros.
+D 2018-07-10T05:11:03.432
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F Makefile.in 0a3a6c81e6fcb969ff9106e882f0a08547014ba463cb6beca4c4efaecc924ee6
@@ -495,7 +495,7 @@ F src/printf.c 7f6f3cba8e0c49c19e30a1ff4e9aeda6e06814dcbad4b664a69e1b6cb6e7e365
 F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384
 F src/resolve.c 1f965d00b4c26b7eb886b90c687069f5db0d05157dbc1ca406fe88e990eac671
 F src/rowset.c 7b7e7e479212e65b723bf40128c7b36dc5afdfac
-F src/select.c ac70f376d02875dac5349b824f9dbd4d444cb27aeb98edf72ae5bc8dec91f20e
+F src/select.c c06d56c1d5931456b2507ac8cf8205e83492a309b685e3978953f0b0156af191
 F src/shell.c.in f1c79c537117ee61317a5ed85cdbcb854998cd690eb34ab803779358a2ace780
 F src/sqlite.h.in 36f0b3f88241863530f4b7e57e673e19311dd609ec4edad83b23291928cdf853
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
@@ -584,7 +584,7 @@ F src/where.c 0bcbf9e191ca07f9ea2008aa80e70ded46bcdffd26560c83397da501f00aece6
 F src/whereInt.h b90ef9b9707ef750eab2a7a080c48fb4900315033274689def32d0cf5a81ebe4
 F src/wherecode.c 3317f2b083a66d3e65a03edf316ade4ccb0a99c9956273282ebb579b95d4ba96
 F src/whereexpr.c 571618c67a3eb5ce0f1158c2792c1aee9b4a4a264392fc4fb1b35467f80abf9a
-F src/window.c 60b374948d2f620dcd75656b5989cc81a9adbfe1a501d56e4ec2ff31b566fab9
+F src/window.c df2bc08168ec3d7509d4674b0e52f90f83011425e0d6519240cec051d16cbd62
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/affinity2.test a6d901b436328bd67a79b41bb0ac2663918fe3bd
 F test/affinity3.test 6a101af2fc945ce2912f6fe54dd646018551710d
@@ -1746,7 +1746,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 0c8a2f257fb71b2b053c4a2028db063e92dd9ff585a17fa22a70f9223fb11e75
-R f04a87b92e27af849599e79f96e43d61
+P 5023b1b85b883a716a5da673740b6effe214ee0490f4ca45f161bb8b04784366
+R 1d4ea7412d930566b30febcbbea41480
 U drh
-Z 40c0c33790af4ea254b922890c6786fb
+Z a8f24d1ff4685d87f042dd3f45af12cc
diff --git a/manifest.uuid b/manifest.uuid
index b4002a0e18..d0d5647ce8 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-5023b1b85b883a716a5da673740b6effe214ee0490f4ca45f161bb8b04784366
\ No newline at end of file
+a9a307265b0626b3e9df69534c8eacf18413ea31784c9d931eadcff515d3dd84
\ No newline at end of file
diff --git a/src/select.c b/src/select.c
index 24f11199bc..2fd2fb753f 100644
--- a/src/select.c
+++ b/src/select.c
@@ -5940,9 +5940,11 @@ int sqlite3Select(
 
       sqlite3VdbeAddOp2(v, OP_Goto, 0, iBreak);
       sqlite3VdbeResolveLabel(v, addrGosub);
+      VdbeNoopComment((v, "SELECT inner-loop subroutine"));
       selectInnerLoop(pParse, p, -1, &sSort, &sDistinct, pDest, iCont, iBreak);
       sqlite3VdbeResolveLabel(v, iCont);
       sqlite3VdbeAddOp1(v, OP_Return, regGosub);
+      VdbeComment((v, "end inner-loop subroutine"));
       sqlite3VdbeResolveLabel(v, iBreak);
     }else
 #endif /* SQLITE_OMIT_WINDOWFUNC */
diff --git a/src/window.c b/src/window.c
index b531c4b8c3..5caaaa6ddb 100644
--- a/src/window.c
+++ b/src/window.c
@@ -1034,9 +1034,13 @@ static void windowCheckIntValue(Parse *pParse, int reg, int eCond){
   assert( eCond==0 || eCond==1 || eCond==2 );
   sqlite3VdbeAddOp2(v, OP_Integer, 0, regZero);
   sqlite3VdbeAddOp2(v, OP_MustBeInt, reg, sqlite3VdbeCurrentAddr(v)+2);
-  VdbeCoverage(v);
+  VdbeCoverageIf(v, eCond==0);
+  VdbeCoverageIf(v, eCond==1);
+  VdbeCoverageIf(v, eCond==2);
   sqlite3VdbeAddOp3(v, aOp[eCond], regZero, sqlite3VdbeCurrentAddr(v)+2, reg);
-  VdbeCoverage(v);
+  VdbeCoverageIf(v, eCond==0);
+  VdbeCoverageIf(v, eCond==1);
+  VdbeCoverageIf(v, eCond==2);
   sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_ERROR, OE_Abort);
   sqlite3VdbeAppendP4(v, (void*)azErr[eCond], P4_STATIC);
   sqlite3ReleaseTempReg(pParse, regZero);
@@ -1250,6 +1254,7 @@ static void windowPartitionCache(
     VdbeCoverage(v);
     sqlite3VdbeAddOp3(v, OP_Copy, regNewPart, pMWin->regPart, nPart-1);
     sqlite3VdbeAddOp2(v, OP_Gosub, regFlushPart, lblFlushPart);
+    VdbeComment((v, "call flush_partition"));
   }
 
   /* Buffer the current row in the ephemeral table. */
@@ -1261,6 +1266,7 @@ static void windowPartitionCache(
 
   /* Invoke "flush_partition" to deal with the final (or only) partition */
   sqlite3VdbeAddOp2(v, OP_Gosub, regFlushPart, lblFlushPart);
+  VdbeComment((v, "call flush_partition"));
 }
 
 /*
@@ -1588,6 +1594,7 @@ static void windowCodeRowExprStep(
   sqlite3VdbeResolveLabel(v, lblFlushPart);
   sqlite3VdbeAddOp2(v, OP_Once, 0, sqlite3VdbeCurrentAddr(v)+3);
   VdbeCoverage(v);
+  VdbeComment((v, "Flush_partition subroutine"));
   sqlite3VdbeAddOp2(v, OP_OpenDup, csrStart, pMWin->iEphCsr);
   sqlite3VdbeAddOp2(v, OP_OpenDup, csrEnd, pMWin->iEphCsr);
 
@@ -1709,6 +1716,7 @@ static void windowCodeRowExprStep(
   sqlite3VdbeResolveLabel(v, lblFlushDone);
   sqlite3VdbeAddOp1(v, OP_ResetSorter, pMWin->iEphCsr);
   sqlite3VdbeAddOp1(v, OP_Return, regFlushPart);
+  VdbeComment((v, "end flush_partition subroutine"));
 
   /* Jump to here to skip over flush_partition */
   sqlite3VdbeJumpHere(v, addrGoto);