Simplifications to the way UnpackedRecord objects are allocated. Smaller

and faster code that also fixes a subtle (currently unreachable) bug.

FossilOrigin-Name: f7ab01f254cd9d7006b8dec29adb234a671b8e6f

manifest

@@ -1,5 +1,5 @@
-C Change\sthe\sOP_IfNotZero\sopcode\sso\sthat\sit\sdecrements\sregister\sP1\sby\s1\srather\nthan\sthe\svalue\sin\sP3,\sand\sso\sthat\sit\sonly\sdecrements\sif\soriginally\spositive.\nThis\savoids\sdecrementing\sthe\ssmallest\s64-bit\ssigned\sinteger.
+C Simplifications\sto\sthe\sway\sUnpackedRecord\sobjects\sare\sallocated.\s\sSmaller\nand\sfaster\scode\sthat\salso\sfixes\sa\ssubtle\s(currently\sunreachable)\sbug.
-D 2016-12-18T17:42:00.870
+D 2016-12-21T19:45:54.698
 F Makefile.in 41bd4cad981487345c4a84081074bcdb876e4b2e
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc b8ca53350ae545e3562403d5da2a69cec79308da
@@ -331,7 +331,7 @@ F src/auth.c 930b376a9c56998557367e6f7f8aaeac82a2a792
 F src/backup.c faf17e60b43233c214aae6a8179d24503a61e83b
 F src/bitvec.c 17ea48eff8ba979f1f5b04cc484c7bb2be632f33
 F src/btmutex.c bc87dd3b062cc26edfe79918de2200ccb8d41e73
-F src/btree.c b2055dff0b94e03eaad48a760984a2d8e39244e6
+F src/btree.c 2e07a5a6d705c1439392460f4044ea4179d9cd40
 F src/btree.h 2349a588abcd7e0c04f984e15c5c777b61637583
 F src/btreeInt.h 10c4b77c2fb399580babbcc7cf652ac10dba796e
 F src/build.c 52970b6cf3cf3107551a5d6dd668b0b261b0b491
@@ -455,14 +455,14 @@ F src/update.c 1da7c462110bffed442a42884cb0d528c1db46d8
 F src/utf.c 699001c79f28e48e9bcdf8a463da029ea660540c
 F src/util.c e68e8ced7328f22d2cf7b4c898c394a0de34cdf1
 F src/vacuum.c 33c174b28886b2faf26e503b5a49a1c01a9b1c16
-F src/vdbe.c 4537452b85817772f159751d6b05799f3f4b09f5
+F src/vdbe.c 0106e0d4f0d39aced35c150a6919d2878df6b1e0
-F src/vdbe.h 0c74f6305fb43b9b282dacaff102272370e327d4
+F src/vdbe.h 50ee139f9c68fff91be1d717ed3a6abbd496919c
 F src/vdbeInt.h 42e498dbe96475dbb3fda3d85d8fd2a87eff60a2
-F src/vdbeapi.c ea4e2dc2213cc6bd7bee375a29a9b51c31b93ae0
+F src/vdbeapi.c 129a2a1103e29fe839e137c641ff42b8066667b5
-F src/vdbeaux.c f5edc89007f8a49e224089a4a4dddbc11bd38213
+F src/vdbeaux.c 7f67112cc57b2fa37b777fbf03eb32c96b337cfe
 F src/vdbeblob.c f4f98ea672b242f807c08c92c7faaa79e5091b65
 F src/vdbemem.c d3fd85b7b7ef3eb75de29c6d7e1d10d3ca78b4fd
-F src/vdbesort.c bb34eed4fb52e11ac037dccea4ee3190594c7f9e
+F src/vdbesort.c eda25cb2d1727efca6f7862fea32b8aa33c0face
 F src/vdbetrace.c 41963d5376f0349842b5fc4aaaaacd7d9cdc0834
 F src/vtab.c c4bbe0f870f52036553f8098aee0703997f0577a
 F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
@@ -1539,7 +1539,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 50325abe79b6a79b09ec6a1cee7d80ca02337428
+P 165c044686212fbf7182dd560ad1e57eb4cc9838
-R e3435f7f9ecf849784b4c50691f0f18b
+R 4dcc327309935c00dd451588970c060d
 U drh
-Z 8b4cd82f585875ac24b32af2b88bc83b
+Z 2858688c4db6360d8c3b1c8fd6aab8f2

manifest.uuid

@@ -1 +1 @@
-165c044686212fbf7182dd560ad1e57eb4cc9838
+f7ab01f254cd9d7006b8dec29adb234a671b8e6f

src/btree.c

@@ -763,26 +763,23 @@ static int btreeMoveto(
 ){
   int rc;                    /* Status code */
   UnpackedRecord *pIdxKey;   /* Unpacked index key */
-  char aSpace[384];          /* Temp space for pIdxKey - to avoid a malloc */
-  char *pFree = 0;
 
   if( pKey ){
     assert( nKey==(i64)(int)nKey );
-    pIdxKey = sqlite3VdbeAllocUnpackedRecord(
+    pIdxKey = sqlite3VdbeAllocUnpackedRecord(pCur->pKeyInfo);
-        pCur->pKeyInfo, aSpace, sizeof(aSpace), &pFree
-    );
     if( pIdxKey==0 ) return SQLITE_NOMEM_BKPT;
     sqlite3VdbeRecordUnpack(pCur->pKeyInfo, (int)nKey, pKey, pIdxKey);
     if( pIdxKey->nField==0 ){
-      sqlite3DbFree(pCur->pKeyInfo->db, pFree);
+      rc = SQLITE_CORRUPT_BKPT;
-      return SQLITE_CORRUPT_BKPT;
+      goto moveto_done;
     }
   }else{
     pIdxKey = 0;
   }
   rc = sqlite3BtreeMovetoUnpacked(pCur, pIdxKey, nKey, bias, pRes);
-  if( pFree ){
+moveto_done:
-    sqlite3DbFree(pCur->pKeyInfo->db, pFree);
+  if( pIdxKey ){
+    sqlite3DbFree(pCur->pKeyInfo->db, pIdxKey);
   }
   return rc;
 }

src/vdbe.c

@@ -3985,10 +3985,9 @@ case OP_Found: {        /* jump, in3 */
   int ii;
   VdbeCursor *pC;
   int res;
-  char *pFree;
+  UnpackedRecord *pFree;
   UnpackedRecord *pIdxKey;
   UnpackedRecord r;
-  char aTempRec[ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*4 + 7];
 
 #ifdef SQLITE_TEST
   if( pOp->opcode!=OP_NoConflict ) sqlite3_found_count++;
@@ -4005,7 +4004,6 @@ case OP_Found: {        /* jump, in3 */
   assert( pC->eCurType==CURTYPE_BTREE );
   assert( pC->uc.pCursor!=0 );
   assert( pC->isTable==0 );
-  pFree = 0;
   if( pOp->p4.i>0 ){
     r.pKeyInfo = pC->pKeyInfo;
     r.nField = (u16)pOp->p4.i;
@@ -4018,10 +4016,9 @@ case OP_Found: {        /* jump, in3 */
     }
 #endif
     pIdxKey = &r;
+    pFree = 0;
   }else{
-    pIdxKey = sqlite3VdbeAllocUnpackedRecord(
+    pFree = pIdxKey = sqlite3VdbeAllocUnpackedRecord(pC->pKeyInfo);
-        pC->pKeyInfo, aTempRec, sizeof(aTempRec), &pFree
-    );
     if( pIdxKey==0 ) goto no_mem;
     assert( pIn3->flags & MEM_Blob );
     (void)ExpandBlob(pIn3);
@@ -4041,7 +4038,7 @@ case OP_Found: {        /* jump, in3 */
     }
   }
   rc = sqlite3BtreeMovetoUnpacked(pC->uc.pCursor, pIdxKey, 0, 0, &res);
-  sqlite3DbFree(db, pFree);
+  if( pFree ) sqlite3DbFree(db, pFree);
   if( rc!=SQLITE_OK ){
     goto abort_due_to_error;
   }

src/vdbe.h

@@ -233,7 +233,7 @@ int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
 void sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,UnpackedRecord*);
 int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
 int sqlite3VdbeRecordCompareWithSkip(int, const void *, UnpackedRecord *, int);
-UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(KeyInfo *, char *, int, char **);
+UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(KeyInfo*);
 
 typedef int (*RecordCompare)(int,const void*,UnpackedRecord*);
 RecordCompare sqlite3VdbeFindCompare(UnpackedRecord*);

src/vdbeapi.c

@@ -1657,10 +1657,9 @@ static UnpackedRecord *vdbeUnpackRecord(
   int nKey, 
   const void *pKey
 ){
-  char *dummy;                    /* Dummy argument for AllocUnpackedRecord() */
   UnpackedRecord *pRet;           /* Return value */
 
-  pRet = sqlite3VdbeAllocUnpackedRecord(pKeyInfo, 0, 0, &dummy);
+  pRet = sqlite3VdbeAllocUnpackedRecord(pKeyInfo);
   if( pRet ){
     memset(pRet->aMem, 0, sizeof(Mem)*(pKeyInfo->nField+1));
     sqlite3VdbeRecordUnpack(pKeyInfo, nKey, pKey, pRet);

src/vdbeaux.c

@@ -3494,30 +3494,13 @@ u32 sqlite3VdbeSerialGet(
 ** If an OOM error occurs, NULL is returned.
 */
 UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(
-  KeyInfo *pKeyInfo,              /* Description of the record */
+  KeyInfo *pKeyInfo               /* Description of the record */
-  char *pSpace,                   /* Unaligned space available */
-  int szSpace,                    /* Size of pSpace[] in bytes */
-  char **ppFree                   /* OUT: Caller should free this pointer */
 ){
   UnpackedRecord *p;              /* Unpacked record to return */
-  int nOff;                       /* Increment pSpace by nOff to align it */
   int nByte;                      /* Number of bytes required for *p */
-
-  /* We want to shift the pointer pSpace up such that it is 8-byte aligned.
-  ** Thus, we need to calculate a value, nOff, between 0 and 7, to shift 
-  ** it by.  If pSpace is already 8-byte aligned, nOff should be zero.
-  */
-  nOff = (8 - (SQLITE_PTR_TO_INT(pSpace) & 7)) & 7;
   nByte = ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*(pKeyInfo->nField+1);
-  if( nByte>szSpace+nOff ){
+  p = (UnpackedRecord *)sqlite3DbMallocRaw(pKeyInfo->db, nByte);
-    p = (UnpackedRecord *)sqlite3DbMallocRaw(pKeyInfo->db, nByte);
+  if( !p ) return 0;
-    *ppFree = (char *)p;
-    if( !p ) return 0;
-  }else{
-    p = (UnpackedRecord*)&pSpace[nOff];
-    *ppFree = 0;
-  }
-
   p->aMem = (Mem*)&((char*)p)[ROUND8(sizeof(UnpackedRecord))];
   assert( pKeyInfo->aSortOrder!=0 );
   p->pKeyInfo = pKeyInfo;

src/vdbesort.c

@@ -1327,12 +1327,8 @@ static int vdbeSorterOpenTempFile(
 */
 static int vdbeSortAllocUnpacked(SortSubtask *pTask){
   if( pTask->pUnpacked==0 ){
-    char *pFree;
+    pTask->pUnpacked = sqlite3VdbeAllocUnpackedRecord(pTask->pSorter->pKeyInfo);
-    pTask->pUnpacked = sqlite3VdbeAllocUnpackedRecord(
+    if( pTask->pUnpacked==0 ) return SQLITE_NOMEM_BKPT;
-        pTask->pSorter->pKeyInfo, 0, 0, &pFree
-    );
-    assert( pTask->pUnpacked==(UnpackedRecord*)pFree );
-    if( pFree==0 ) return SQLITE_NOMEM_BKPT;
     pTask->pUnpacked->nField = pTask->pSorter->pKeyInfo->nField;
     pTask->pUnpacked->errCode = 0;
   }
@@ -2733,9 +2729,7 @@ int sqlite3VdbeSorterCompare(
   r2 = pSorter->pUnpacked;
   pKeyInfo = pCsr->pKeyInfo;
   if( r2==0 ){
-    char *p;
+    r2 = pSorter->pUnpacked = sqlite3VdbeAllocUnpackedRecord(pKeyInfo);
-    r2 = pSorter->pUnpacked = sqlite3VdbeAllocUnpackedRecord(pKeyInfo,0,0,&p);
-    assert( pSorter->pUnpacked==(UnpackedRecord*)p );
     if( r2==0 ) return SQLITE_NOMEM_BKPT;
     r2->nField = nKeyCol;
   }