1 files changed, 23 insertions, 41 deletions

diff --git a/src/vdbe.c b/src/vdbe.c
index 7c8d2a4ef..dbfa18a5e 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -7442,13 +7442,15 @@ case OP_MaxPgcnt: {            /* out2 */
 }
 #endif
 
-/* Opcode: Function0 P1 P2 P3 P4 P5
+/* Opcode: Function P1 P2 P3 P4 *
 ** Synopsis: r[P3]=func(r[P2@P5])
 **
-** Invoke a user function (P4 is a pointer to a FuncDef object that
-** defines the function) with P5 arguments taken from register P2 and
-** successors.  The result of the function is stored in register P3.
-** Register P3 must not be one of the function inputs.
+** Invoke a user function (P4 is a pointer to an sqlite3_context object that
+** contains a pointer to the function to be run) with arguments taken
+** from register P2 and successors.  The number of arguments is in
+** the sqlite3_context object that P4 points to.
+** The result of the function is stored
+** in register P3.  Register P3 must not be one of the function inputs.
 **
 ** P1 is a 32-bit bitmask indicating whether or not each argument to the 
 ** function was determined to be constant at compile time. If the first
@@ -7457,14 +7459,16 @@ case OP_MaxPgcnt: {            /* out2 */
 ** sqlite3_set_auxdata() API may be safely retained until the next
 ** invocation of this opcode.
 **
-** See also: Function, AggStep, AggFinal
+** See also: AggStep, AggFinal, PureFunc
 */
-/* Opcode: Function P1 P2 P3 P4 P5
+/* Opcode: PureFunc P1 P2 P3 P4 *
 ** Synopsis: r[P3]=func(r[P2@P5])
 **
 ** Invoke a user function (P4 is a pointer to an sqlite3_context object that
-** contains a pointer to the function to be run) with P5 arguments taken
-** from register P2 and successors.  The result of the function is stored
+** contains a pointer to the function to be run) with arguments taken
+** from register P2 and successors.  The number of arguments is in
+** the sqlite3_context object that P4 points to.
+** The result of the function is stored
 ** in register P3.  Register P3 must not be one of the function inputs.
 **
 ** P1 is a 32-bit bitmask indicating whether or not each argument to the 
@@ -7474,40 +7478,16 @@ case OP_MaxPgcnt: {            /* out2 */
 ** sqlite3_set_auxdata() API may be safely retained until the next
 ** invocation of this opcode.
 **
-** SQL functions are initially coded as OP_Function0 with P4 pointing
-** to a FuncDef object.  But on first evaluation, the P4 operand is
-** automatically converted into an sqlite3_context object and the operation
-** changed to this OP_Function opcode.  In this way, the initialization of
-** the sqlite3_context object occurs only once, rather than once for each
-** evaluation of the function.
+** This opcode works exactly like OP_Function.  The only difference is in
+** its name.  This opcode is used in places where the function must be
+** purely non-deterministic.  Some built-in date/time functions can be
+** either determinitic of non-deterministic, depending on their arguments.
+** When those function are used in a non-deterministic way, they will check
+** to see if they were called using OP_PureFunc instead of OP_Function, and
+** if they were, they throw an error.
 **
-** See also: Function0, AggStep, AggFinal
+** See also: AggStep, AggFinal, Function
 */
-case OP_PureFunc0:              /* group */
-case OP_Function0: {            /* group */
-  int n;
-  sqlite3_context *pCtx;
-
-  assert( pOp->p4type==P4_FUNCDEF );
-  n = pOp->p5;
-  assert( pOp->p3>0 && pOp->p3<=(p->nMem+1 - p->nCursor) );
-  assert( n==0 || (pOp->p2>0 && pOp->p2+n<=(p->nMem+1 - p->nCursor)+1) );
-  assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+n );
-  pCtx = sqlite3DbMallocRawNN(db, sizeof(*pCtx) + (n-1)*sizeof(sqlite3_value*));
-  if( pCtx==0 ) goto no_mem;
-  pCtx->pOut = 0;
-  pCtx->pFunc = pOp->p4.pFunc;
-  pCtx->iOp = (int)(pOp - aOp);
-  pCtx->pVdbe = p;
-  pCtx->isError = 0;
-  pCtx->argc = n;
-  pOp->p4type = P4_FUNCCTX;
-  pOp->p4.pCtx = pCtx;
-  assert( OP_PureFunc == OP_PureFunc0+2 );
-  assert( OP_Function == OP_Function0+2 );
-  pOp->opcode += 2;
-  /* Fall through into OP_Function */
-}
 case OP_PureFunc:              /* group */
 case OP_Function: {            /* group */
   int i;
@@ -7522,9 +7502,11 @@ case OP_Function: {            /* group */
   ** reinitializes the relavant parts of the sqlite3_context object */
   pOut = &aMem[pOp->p3];
   if( pCtx->pOut != pOut ){
+    pCtx->pVdbe = p;
     pCtx->pOut = pOut;
     for(i=pCtx->argc-1; i>=0; i--) pCtx->argv[i] = &aMem[pOp->p2+i];
   }
+  assert( pCtx->pVdbe==p );
 
   memAboutToChange(p, pOut);
 #ifdef SQLITE_DEBUG