Fixes to the logic for constraint check reordering during upsert.

Improved comments on constraint check bytecode.  Add an assert that
prevents the same label from being resolved more than once.

FossilOrigin-Name: 1ddbb0ff5586ef5ca987e4309979f24f95eea883ed68937094a2db2d61e75657

manifest

@@ -1,5 +1,5 @@
-C During\sPRAGMA\svdbe_addoptrace=ON,\sshow\scalls\sto\ssqlite3VdbeResolveLabel()\nin\sthe\sdebugging\soutput.
+C Fixes\sto\sthe\slogic\sfor\sconstraint\scheck\sreordering\sduring\supsert.\nImproved\scomments\son\sconstraint\scheck\sbytecode.\s\sAdd\san\sassert\sthat\nprevents\sthe\ssame\slabel\sfrom\sbeing\sresolved\smore\sthan\sonce.
-D 2018-04-17T19:29:58.545
+D 2018-04-17T20:06:24.300
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F Makefile.in 5ce9343cba9c189046f1afe6d2bcc1f68079439febc05267b98aec6ecc752439
@@ -452,7 +452,7 @@ F src/hash.c a12580e143f10301ed5166ea4964ae2853d3905a511d4e0c44497245c7ce1f7a
 F src/hash.h ab34c5c54a9e9de2e790b24349ba5aab3dbb4fd4
 F src/hwtime.h 747c1bbe9df21a92e9c50f3bbec1de841dc5e5da
 F src/in-operator.md 10cd8f4bcd225a32518407c2fb2484089112fd71
-F src/insert.c 771dc7631afe203f867c74c37357d57d16127a7e5075e0d735564b9160eb6516
+F src/insert.c 326dfb5d6f738c48b772f897401f25923c2fdd569258014d57244594985a2baa
 F src/legacy.c 134ab3e3fae00a0f67a5187981d6935b24b337bcf0f4b3e5c9fa5763da95bf4e
 F src/loadext.c f6e4e416a736369f9e80eba609f0acda97148a8b0453784d670c78d3eed2f302
 F src/main.c 1648fc7a9bcfdbfd9a9a04af96ff2796c3164b3f3c7e56ed63a3c51cd11d198d
@@ -565,7 +565,7 @@ F src/vdbe.c 066a4e1de2ed83e253adfd2e97a684cf562eaa41d31ee7f3d3e4c8aea4485a55
 F src/vdbe.h 134beb7a12a6213c00eba58febaede33447cc4441bc568a0d9c144b33fc3720a
 F src/vdbeInt.h 95f7adfdc5c8f1353321f55a6c5ec00a90877e3b85af5159e393afb41ff54110
 F src/vdbeapi.c 29d2baf9c1233131ec467d7bed1b7c8a03c27579048d768c4b04acf427838858
-F src/vdbeaux.c 38517c96784f9fb19c3bfcfb4737e6c56496f23bf3dcd6a659e0fcee47a0365d
+F src/vdbeaux.c 42c40f64bb718088d0d838cf2396c8c478be52c66dcbf3af2d3c353df6162b76
 F src/vdbeblob.c f5c70f973ea3a9e915d1693278a5f890dc78594300cf4d54e64f2b0917c94191
 F src/vdbemem.c 414e28d3a7e2a8bee2bb247de115dcbc68e3cbac284d5862d077002f7a93bce1
 F src/vdbesort.c 731a09e5cb9e96b70c394c1b7cf3860fbe84acca7682e178615eb941a3a0ef2f
@@ -1722,7 +1722,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P f3d91cad929cfbee8f621425f55b5f12e79567362cf8769a786adb3e1bbef214
+P 9ff07a06cef6e04777d2d5b81f96e8626e835382e62320ecf17b3ff73573e23e
-R 60d71468a24d9ed1562da4014c73e7db
+R 2511be33be4d6ad227cb9bb37ba0a227
 U drh
-Z bc5630c7bf75a2d7aeeb288bf5244551
+Z 7a27698f9fbf02f710a4c8fd1b269116

manifest.uuid

@@ -1 +1 @@
-9ff07a06cef6e04777d2d5b81f96e8626e835382e62320ecf17b3ff73573e23e
+1ddbb0ff5586ef5ca987e4309979f24f95eea883ed68937094a2db2d61e75657

src/insert.c

@@ -1507,7 +1507,7 @@ void sqlite3GenerateConstraintChecks(
 
     /* Check to see if the new rowid already exists in the table.  Skip
     ** the following conflict logic if it does not. */
-    VdbeNoopComment((v, "constraint checks for ROWID"));
+    VdbeNoopComment((v, "uniqueness check for ROWID"));
     sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, addrRowidOk, regNewData);
     VdbeCoverage(v);
 
@@ -1603,17 +1603,21 @@ void sqlite3GenerateConstraintChecks(
     int addrUniqueOk;    /* Jump here if the UNIQUE constraint is satisfied */
 
     if( aRegIdx[ix]==0 ) continue;  /* Skip indices that do not change */
-    VdbeNoopComment((v, "constraint checks for %s", pIdx->zName));
+    if( pUpIdx==pIdx ){
+      addrUniqueOk = sAddr.upsertBtm;
+      upsertBypass = sqlite3VdbeGoto(v, 0);
+      VdbeComment((v, "Skip upsert subroutine"));
+      sqlite3VdbeResolveLabel(v, sAddr.upsertTop);
+    }else{
+      addrUniqueOk = sqlite3VdbeMakeLabel(v);
+    }
+    VdbeNoopComment((v, "uniqueness check for %s", pIdx->zName));
     if( bAffinityDone==0 ){
       sqlite3TableAffinity(v, pTab, regNewData+1);
       bAffinityDone = 1;
     }
     iThisCur = iIdxCur+ix;
-    if( pUpIdx==pIdx ){
+
-      addrUniqueOk = sAddr.upsertBtm;
-    }else{
-      addrUniqueOk = sqlite3VdbeMakeLabel(v);
-    }
 
     /* Skip partial indices for which the WHERE clause is not true */
     if( pIdx->pPartIdxWhere ){
@@ -1683,9 +1687,6 @@ void sqlite3GenerateConstraintChecks(
       }else{
         onError = OE_Update;  /* DO UPDATE */
       }
-      upsertBypass = sqlite3VdbeGoto(v, 0);
-      VdbeComment((v, "Upsert bypass"));
-      sqlite3VdbeResolveLabel(v, sAddr.upsertTop);
     }
 
     /* Collision detection may be omitted if all of the following are true:
@@ -1802,10 +1803,13 @@ void sqlite3GenerateConstraintChecks(
         break;
       }
     }
+    if( pUpIdx==pIdx ){
+      sqlite3VdbeJumpHere(v, upsertBypass);
+    }else{
       sqlite3VdbeResolveLabel(v, addrUniqueOk);
+    }
     sqlite3ExprCachePop(pParse);
     if( regR!=regIdx ) sqlite3ReleaseTempRange(pParse, regR, nPkField);
-    if( pUpIdx==pIdx ) sqlite3VdbeJumpHere(v, upsertBypass);
 
   }
   reorderConstraintChecks(v, &sAddr);

src/vdbeaux.c

@@ -397,6 +397,7 @@ void sqlite3VdbeResolveLabel(Vdbe *v, int x){
       printf("RESOLVE LABEL %d to %d\n", x, v->nOp);
     }
 #endif
+    assert( p->aLabel[j]==(-1) );
     p->aLabel[j] = v->nOp;
   }
 }