Rename sqlite3ExprCodeAtInit() to sqlite3ExprCodeRunJustOnce().

Other changes to make the new code cleaner.  Test cases added.

FossilOrigin-Name: d7f18489978fdbbe3ab317485518cac91a75416ccef55898301afdd76d3b415b

diff --git a/manifest b/manifest
index 11b5b9c942c2b447c2d480484f57970be1e41476..b990d901bdb186d7d13ee82914c2e5801dfd79ea 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Do\snot\sfactor\sout\sconstant\sfunctions\sinto\sthe\sinitialization\ssection\sat\sthe\nend\sof\sthe\sprepared\sstatement,\sbe\scause\sif\sthey\sthrow\san\sexception,\sit\swill\nabort\sthe\sstatement\seven\sif\sthe\sfunction\sis\snever\scalled.\s\sBetter\sto\sput\nconstant\sfunctions\sin\san\sOP_Once\sblock.
-D 2020-03-11T17:58:27.142
+C Rename\ssqlite3ExprCodeAtInit()\sto\ssqlite3ExprCodeRunJustOnce().\nOther\schanges\sto\smake\sthe\snew\scode\scleaner.\s\sTest\scases\sadded.
+D 2020-03-11T19:41:49.390
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -483,7 +483,7 @@ F src/date.c 6c408fdd2e9ddf6e8431aba76315a2d061bea2cec8fbb75e25d7c1ba08274712
 F src/dbpage.c 8a01e865bf8bc6d7b1844b4314443a6436c07c3efe1d488ed89e81719047833a
 F src/dbstat.c 0f55297469d4244ab7df395849e1af98eb5e95816af7c661e7d2d8402dea23da
 F src/delete.c 11000121c4281c0bce4e41db29addfaea0038eaa127ece02557c9207bc3e541d
-F src/expr.c 137db48827025f68792824eaf8e4c66612dbd160cf5cafe6ae93b27eed101e12
+F src/expr.c ed718ee2206166c9c2fc4fe89eadb1f369318aeb8645e06033566b387970fb9a
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c 4b575423b0a5d4898b1a7868ce985cf1a8ad91c741c9abbb108ff02536d20f41
 F src/func.c 108577cebe8a50c86d849a93b99493a54e348dd0b846f00d13b52ca973d5baf4
@@ -536,7 +536,7 @@ F src/shell.c.in f76590931c0cbbfef347f44f81ade6b335f80c46bc6e59b8b6114383a8df30e
 F src/sqlite.h.in 802957feeb249ede54f8dfe99b72aa19e70a0b7737969c46e625dc2f9f2d42b0
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 9c5269260409eb3275324ccace6a13a96f4ad330c708415f70ca6097901ff4ee
-F src/sqliteInt.h ed6885bb0ec82db2503c931fd96c795fc7a4b474dc075c3442a45c3a8523c797
+F src/sqliteInt.h 5f74c1c52b152259ee07f241821620f11736e4f590936cfaf1cbbff9a2f563d3
 F src/sqliteLimit.h 95cb8479ca459496d9c1c6a9f76b38aee12203a56ce1092fe13e50ae2454c032
 F src/status.c 9ff2210207c6c3b4d9631a8241a7d45ab1b26a0e9c84cb07a9b5ce2de9a3b278
 F src/table.c b46ad567748f24a326d9de40e5b9659f96ffff34
@@ -603,7 +603,7 @@ F src/upsert.c 2920de71b20f04fe25eb00b655d086f0ba60ea133c59d7fa3325c49838818e78
 F src/utf.c 95fb6e03a5ca679045c5adccd05380f0addccabef5911abddcb06af069500ab7
 F src/util.c a285c1e026907b69fa2592bd05047a565a1d8a1aef2b73c924b6a8ffe772871a
 F src/vacuum.c 813b510ba887fee6492bcb11f2bf77d7eb58b232b83649136372e0a2fc17f4b9
-F src/vdbe.c 8ad7906cf9aca841b97064fbf62323f53aaf8e4f8251ffa5e152abc5bda806d3
+F src/vdbe.c 6d0cf7ac2d54f78ff2fb55cbef970199695319c0a95bf862c6561d7d2c9f7134
 F src/vdbe.h 51282fbe819ee0e8eeeaab176240860d334c20a12b14f3b363e7f1a4e05d60b9
 F src/vdbeInt.h a17146053a1aa438474012998fe07e314f3df274a61491ad838ad85d848ac051
 F src/vdbeapi.c 1252d80c548711e47a6d84dae88ed4e95d3fbb4e7bd0eaa1347299af7efddf02
@@ -612,7 +612,7 @@ F src/vdbeblob.c 253ed82894924c362a7fa3079551d3554cd1cdace39aa833da77d3bc67e7c1b
 F src/vdbemem.c 39b942ecca179f4f30a32b54579a85d74ccaefa5af2a0ad2700abe5ef0768b22
 F src/vdbesort.c 2be76d26998ce2b3324cdcc9f6443728e54b6c7677c553ad909c7d7cfab587df
 F src/vdbetrace.c fa3bf238002f0bbbdfb66cc8afb0cea284ff9f148d6439bc1f6f2b4c3b7143f0
-F src/vtab.c ad810f9b771cf66eee2762e18eb2b704c97c18ca4b4bf25af7f88ab1fb254d14
+F src/vtab.c 7b704a90515a239c6cdba6a66b1bb3a385e62326cceb5ecb05ec7a091d6b8515
 F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
 F src/wal.c 697424314e40d99f93f548c7bfa526c10e87f4bdf64d5a76a96b999dd7133ebc
 F src/wal.h 606292549f5a7be50b6227bd685fa76e3a4affad71bb8ac5ce4cb5c79f6a176a
@@ -1003,7 +1003,7 @@ F test/fts4rename.test 15fd9985c2bce6dea20da2245b22029ec89bd4710ed317c4c53abbe3c
 F test/fts4umlaut.test fcaca4471de7e78c9d1f7e8976e3e8704d7d8ad979d57a739d00f3f757380429
 F test/fts4unicode.test ceca76422abc251818cb25dabe33d3c3970da5f7c90e1540f190824e6b3a7c95
 F test/full.test 6b3c8fb43c6beab6b95438c1675374b95fab245d
-F test/func.test b7f1a706d1bb8de103a24bd0c30c9e3dc3eedf0df24aabc54b0a4f6e08742622
+F test/func.test f673822636fb8ed618dd2b80230d16e495d19c8f2e2e7d6c22e93e2b3de097ad
 F test/func2.test 772d66227e4e6684b86053302e2d74a2500e1e0f
 F test/func3.test 2bb0f31ab7baaed690b962a88544d7be6b34fa389364bc36a44e441ed3e3f1e6
 F test/func4.test a94858a8c1f10a408b0b3db439c990b59dbb2349411d503de011ac4e2b5f27a6
@@ -1860,10 +1860,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P fb5a8a9edd0a4f979d6c30278d4ddc73c651f56ae989b4e5983fca36887c5ceb
-R cf3e121998a086e24f73b7daa3777948
-T *branch * do-not-factor-functions
-T *sym-do-not-factor-functions *
-T -sym-trunk *
+P 97a18a5cd701848a9660385e31bffe2c397e3cfe57ccdb876f44d08c00d1d39a
+R bb18f5b4c4c1d8067c8d33e0ad339acb
 U drh
-Z 4a780ea0d068b9c3f4aeae83f545f604
+Z 791b16818e473b4676673e9f9494706b

diff --git a/manifest.uuid b/manifest.uuid
index 3625ef547adafe8cb8c9355cda3999486fe866c5..9e7309105a3d2766b7e7e6e650902dfc5ba0b89d 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-97a18a5cd701848a9660385e31bffe2c397e3cfe57ccdb876f44d08c00d1d39a
\ No newline at end of file
+d7f18489978fdbbe3ab317485518cac91a75416ccef55898301afdd76d3b415b
\ No newline at end of file

diff --git a/src/expr.c b/src/expr.c
index 8c0768bb7efaa293f52dffa61ad3a7750522d828..8587f5ec780edb9ffa12311e6c9c2adb37482bc7 100644 (file)
--- a/src/expr.c
+++ b/src/expr.c
@@ -2096,7 +2096,7 @@ int sqlite3ExprIsConstant(Expr *p){
 **
 ** When this routine returns true, it indicates that the expression
 ** can be added to the pParse->pConstExpr list and evaluated once when
-** the prepared statement starts up.  See sqlite3ExprCodeAtInit().
+** the prepared statement starts up.  See sqlite3ExprCodeRunJustOnce().
 */
 int sqlite3ExprIsConstantNotJoin(Expr *p){
   return exprIsConst(p, 2, 0);
@@ -4127,9 +4127,9 @@ expr_code_doover:
 #endif
 
       if( ConstFactorOk(pParse) && sqlite3ExprIsConstantNotJoin(pExpr) ){
-        /* SQL functions can be expensive. So try to move constant functions
-        ** out of the inner loop, even if that means an extra OP_Copy. */
-        return sqlite3ExprCodeAtInit(pParse, pExpr, -1);
+        /* SQL functions can be expensive. So try to avoid running them
+        ** multiple times if we know they always give the same result */
+        return sqlite3ExprCodeRunJustOnce(pParse, pExpr, -1);
       }
       assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
       assert( !ExprHasProperty(pExpr, EP_TokenOnly) );
@@ -4507,15 +4507,23 @@ expr_code_doover:
 }
 
 /*
-** Factor out the code of the given expression to initialization time.
+** Generate code that will evaluate expression pExpr just one time
+** per prepared statement execution.
+**
+** If the expression uses functions (that might throw an exception) then
+** guard them with an OP_Once opcode to ensure that the code is only executed
+** once. If no functions are involved, then factor the code out and put it at
+** the end of the prepared statement in the initialization section.
 **
 ** If regDest>=0 then the result is always stored in that register and the
 ** result is not reusable.  If regDest<0 then this routine is free to 
 ** store the value whereever it wants.  The register where the expression 
-** is stored is returned.  When regDest<0, two identical expressions will
-** code to the same register.
+** is stored is returned.  When regDest<0, two identical expressions might
+** code to the same register, if they do not contain function calls and hence
+** are factored out into the initialization section at the end of the
+** prepared statement.
 */
-int sqlite3ExprCodeAtInit(
+int sqlite3ExprCodeRunJustOnce(
   Parse *pParse,    /* Parsing context */
   Expr *pExpr,      /* The expression to code when the VDBE initializes */
   int regDest       /* Store the value in this register */
@@ -4532,7 +4540,6 @@ int sqlite3ExprCodeAtInit(
       }
     }
   }
-  if( regDest<0 ) regDest = ++pParse->nMem;
   pExpr = sqlite3ExprDup(pParse->db, pExpr, 0);
   if( pExpr!=0 && ExprHasProperty(pExpr, EP_HasFunc) ){
     Vdbe *v = pParse->pVdbe;
@@ -4541,6 +4548,7 @@ int sqlite3ExprCodeAtInit(
     addr = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
     pParse->okConstFactor = 0;
     if( !pParse->db->mallocFailed ){
+      if( regDest<0 ) regDest = ++pParse->nMem;
       sqlite3ExprCode(pParse, pExpr, regDest);
     }
     pParse->okConstFactor = 1;
@@ -4551,6 +4559,7 @@ int sqlite3ExprCodeAtInit(
     if( p ){
        struct ExprList_item *pItem = &p->a[p->nExpr-1];
        pItem->reusable = regDest<0;
+       if( regDest<0 ) regDest = ++pParse->nMem;
        pItem->u.iConstExprReg = regDest;
     }
     pParse->pConstExpr = p;
@@ -4579,7 +4588,7 @@ int sqlite3ExprCodeTemp(Parse *pParse, Expr *pExpr, int *pReg){
    && sqlite3ExprIsConstantNotJoin(pExpr)
   ){
     *pReg  = 0;
-    r2 = sqlite3ExprCodeAtInit(pParse, pExpr, -1);
+    r2 = sqlite3ExprCodeRunJustOnce(pParse, pExpr, -1);
   }else{
     int r1 = sqlite3GetTempReg(pParse);
     r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
@@ -4636,7 +4645,7 @@ void sqlite3ExprCodeCopy(Parse *pParse, Expr *pExpr, int target){
 */
 void sqlite3ExprCodeFactorable(Parse *pParse, Expr *pExpr, int target){
   if( pParse->okConstFactor && sqlite3ExprIsConstantNotJoin(pExpr) ){
-    sqlite3ExprCodeAtInit(pParse, pExpr, target);
+    sqlite3ExprCodeRunJustOnce(pParse, pExpr, target);
   }else{
     sqlite3ExprCodeCopy(pParse, pExpr, target);
   }
@@ -4696,7 +4705,7 @@ int sqlite3ExprCodeExprList(
     }else if( (flags & SQLITE_ECEL_FACTOR)!=0
            && sqlite3ExprIsConstantNotJoin(pExpr)
     ){
-      sqlite3ExprCodeAtInit(pParse, pExpr, target+i);
+      sqlite3ExprCodeRunJustOnce(pParse, pExpr, target+i);
     }else{
       int inReg = sqlite3ExprCodeTarget(pParse, pExpr, target+i);
       if( inReg!=target+i ){
@@ -5256,21 +5265,7 @@ int sqlite3ExprCompare(Parse *pParse, Expr *pA, Expr *pB, int iTab){
      && ALWAYS((combinedFlags & EP_Reduced)==0)
     ){
       if( pA->iColumn!=pB->iColumn ) return 2;
-      if( pA->op2!=pB->op2 ){
-        if( pA->op==TK_TRUTH ) return 2;
-        if( pA->op==TK_FUNCTION && iTab<0 ){
-          /* Ex: CREATE TABLE t1(a CHECK( a<julianday('now') ));
-          **     INSERT INTO t1(a) VALUES(julianday('now')+10);
-          ** Without this test, sqlite3ExprCodeAtInit() will run on the
-          ** the julianday() of INSERT first, and remember that expression.
-          ** Then sqlite3ExprCodeInit() will see the julianday() in the CHECK
-          ** constraint as redundant, reusing the one from the INSERT, even
-          ** though the julianday() in INSERT lacks the critical NC_IsCheck
-          ** flag.  See ticket [830277d9db6c3ba1] (2019-10-30)
-          */
-          return 2;
-        }
-      }
+      if( pA->op2!=pB->op2 && pA->op==TK_TRUTH ) return 2;
       if( pA->op!=TK_IN && pA->iTable!=pB->iTable && pA->iTable!=iTab ){
         return 2;
       }

diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index a5cf8d141d6c6540fb9e6e6d79acbd2380169a31..7a00b576a00adf6807bb82764cca8fd690cb3db5 100644 (file)
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -4239,7 +4239,7 @@ void sqlite3ExprCodeGeneratedColumn(Parse*, Column*, int);
 #endif
 void sqlite3ExprCodeCopy(Parse*, Expr*, int);
 void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
-int sqlite3ExprCodeAtInit(Parse*, Expr*, int);
+int sqlite3ExprCodeRunJustOnce(Parse*, Expr*, int);
 int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
 int sqlite3ExprCodeTarget(Parse*, Expr*, int);
 int sqlite3ExprCodeExprList(Parse*, ExprList*, int, int, u8);

diff --git a/src/vdbe.c b/src/vdbe.c
index 8501e7319e4d86a7f138547168c7860b380b59e2..a69c35d83aefc394902777be55966e2b133f0da0 100644 (file)
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -1544,7 +1544,6 @@ case OP_Concat: {           /* same as TK_CONCAT, in1, in2, out3 */
   pIn1 = &aMem[pOp->p1];
   pIn2 = &aMem[pOp->p2];
   pOut = &aMem[pOp->p3];
-  testcase( pIn1==pIn2 );
   testcase( pOut==pIn2 );
   assert( pIn1!=pOut );
   flags1 = pIn1->flags;

diff --git a/src/vtab.c b/src/vtab.c
index 6a30f83a918c68e6ff00bef4d0a9ff4505a28552..013511cfb4127cb2fe16da4d95441664a85c8f9d 100644 (file)
--- a/src/vtab.c
+++ b/src/vtab.c
@@ -1113,7 +1113,7 @@ FuncDef *sqlite3VtabOverloadFunction(
   int rc = 0;
 
   /* Check to see the left operand is a column in a virtual table */
-  if( pExpr==0 ) return pDef;
+  if( NEVER(pExpr==0) ) return pDef;
   if( pExpr->op!=TK_COLUMN ) return pDef;
   pTab = pExpr->y.pTab;
   if( pTab==0 ) return pDef;

diff --git a/test/func.test b/test/func.test
index 34a6f18bcf370811753686a203838e17bb8599e2..4b235bedb47301195e3b07e760d538f241346083 100644 (file)
--- a/test/func.test
+++ b/test/func.test
@@ -1477,4 +1477,24 @@ do_execsql_test func-34.10 {
   SELECT * FROM t1;
 } {1 2}
 
+# 2020-03-11 COALESCE() should short-circuit
+# See also ticket 3c9eadd2a6ba0aa5
+# Both issues stem from the fact that functions that could
+# throw exceptions were being factored out into initialization
+# code.  The fix was to put those function calls inside of
+# OP_Once instead.
+#
+reset_db
+do_execsql_test func-35.100 {
+  CREATE TABLE t1(x);
+  SELECT coalesce(x, abs(-9223372036854775808)) FROM t1;
+} {}
+do_execsql_test func-35.110 {
+  SELECT coalesce(x, 'xyz' LIKE printf('%.1000000c','y')) FROM t1;
+} {}
+do_execsql_test func-35.200 {
+  CREATE TABLE t0(c0 CHECK(ABS(-9223372036854775808)));
+  PRAGMA integrity_check;
+} {ok}
+
 finish_test