Improve the comments associated with SQLITE_TEST_REALLOC_STRESS and add

an extra assert() to prove an assumption.

FossilOrigin-Name: 35c454616321d480ecbc4efdf6869bbcdf0d3aa2

manifest

@@ -1,5 +1,5 @@
-C Run\sa\stest\swith\sTEST_REALLOC_STRESS\sand\sOMIT_LOOKASIDE\sdefined\sas\spart\sof\sreleasetest.tcl\son\sLinux/x86-64.
-D 2014-08-12T14:06:13.039
+C Improve\sthe\scomments\sassociated\swith\sSQLITE_TEST_REALLOC_STRESS\sand\sadd\nan\sextra\sassert()\sto\sprove\san\sassumption.
+D 2014-08-12T14:29:20.012
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5eb79e334a5de69c87740edd56af6527dd219308
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -287,7 +287,7 @@ F src/vdbe.c cd8d7e3ecd3e0e0684f6bf48469966335c666883
 F src/vdbe.h c63fad052c9e7388d551e556e119c0bcf6bebdf8
 F src/vdbeInt.h f5513f2b5ac1e2c5128996c7ea23add256a301df
 F src/vdbeapi.c 24e40422382beb774daab11fe9fe9d37e8a04949
-F src/vdbeaux.c d83ca171e5df5fdea95e61b6e935d78c02b9d982
+F src/vdbeaux.c 25d62ef82cf1be2a1255eacac636fa0d943d8b3d
 F src/vdbeblob.c 9205ce9d3b064d9600f8418a897fc88b5687d9ac
 F src/vdbemem.c d90a1e8acf8b63dc9d14cbbea12bfec6cec31394
 F src/vdbesort.c f7f5563bf7d4695ca8f3203f3bf9de96d04ed0b3
@@ -1186,7 +1186,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 0abfd78ceb09b7f7c27c688c8e3fe93268a13b32
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 4c291827224b84487a38e7ccba2edabc0f15b5ba
-R 1284079e980f8822b336e39d17ba6126
-U dan
-Z b89cd6a3a53bd57f0d4f91bd2d9a8d6b
+P a1baf3a7b177728cdfcd6d9345a0d6bf0a8887c0
+R f180a595651acb4f056167092db3a8a0
+U drh
+Z 0f6249f5f46f843c4c724ed2717337d8

manifest.uuid

@@ -1 +1 @@
-a1baf3a7b177728cdfcd6d9345a0d6bf0a8887c0
+35c454616321d480ecbc4efdf6869bbcdf0d3aa2

src/vdbeaux.c

@@ -85,7 +85,8 @@ void sqlite3VdbeSwap(Vdbe *pA, Vdbe *pB){
 
 /*
 ** Resize the Vdbe.aOp array so that it is at least nOp elements larger 
-** its current size. nOp is guaranteed to be less than or equal to 1024.
+** than its current size. nOp is guaranteed to be less than or equal
+** to 1024/sizeof(Op).
 **
 ** If an out-of-memory error occurs while resizing the array, return
 ** SQLITE_NOMEM. In this case Vdbe.aOp and Parse.nOpAlloc remain 
@@ -96,10 +97,13 @@ static int growOpArray(Vdbe *v, int nOp){
   VdbeOp *pNew;
   Parse *p = v->pParse;
 
-  /* If SQLITE_TEST_REALLOC_STRESS is defined and the current op array is
-  ** less than 512 entries in size, grow the op array by the minimum amount 
-  ** required. Otherwise, allocate either double the current size of the 
-  ** array or 1KB of space, whichever is smaller.  */
+  /* The SQLITE_TEST_REALLOC_STRESS compile-time option is designed to force
+  ** more frequent reallocs and hence provide more opportunities for 
+  ** simulated OOM faults.  SQLITE_TEST_REALLOC_STRESS is generally used
+  ** during testing only.  With SQLITE_TEST_REALLOC_STRESS grow the op array
+  ** by the minimum* amount required until the size reaches 512.  Normal
+  ** operation (without SQLITE_TEST_REALLOC_STRESS) is to double the current
+  ** size of the op array or add 1KB of space, whichever is smaller. */
 #ifdef SQLITE_TEST_REALLOC_STRESS
   int nNew = (p->nOpAlloc>=512 ? p->nOpAlloc*2 : p->nOpAlloc+nOp);
 #else
@@ -107,6 +111,7 @@ static int growOpArray(Vdbe *v, int nOp){
   UNUSED_PARAMETER(nOp);
 #endif
 
+  assert( nOp<=(1024/sizeof(Op)) );
   assert( nNew>=(p->nOpAlloc+nOp) );
   pNew = sqlite3DbRealloc(p->db, v->aOp, nNew*sizeof(Op));
   if( pNew ){