/* Opcode: InitCoroutine P1 P2 P3 * *
**
-** Set up register P1 so that it will OP_Yield to the co-routine
+** Set up register P1 so that it will Yield to the coroutine
** located at address P3.
**
-** If P2!=0 then the co-routine implementation immediately follows
-** this opcode. So jump over the co-routine implementation to
+** If P2!=0 then the coroutine implementation immediately follows
+** this opcode. So jump over the coroutine implementation to
** address P2.
+**
+** See also: EndCoroutine
*/
case OP_InitCoroutine: { /* jump */
assert( pOp->p1>0 && pOp->p1<=(p->nMem-p->nCursor) );
/* Opcode: EndCoroutine P1 * * * *
**
-** The instruction at the address in register P1 is an OP_Yield.
-** Jump to the P2 parameter of that OP_Yield.
+** The instruction at the address in register P1 is an Yield.
+** Jump to the P2 parameter of that Yield.
** After the jump, register P1 becomes undefined.
+**
+** See also: InitCoroutine
*/
case OP_EndCoroutine: { /* in1 */
VdbeOp *pCaller;
/* Opcode: Yield P1 P2 * * *
**
-** Swap the program counter with the value in register P1.
+** Swap the program counter with the value in register P1. This
+** has the effect of yielding to a coroutine.
**
-** If the co-routine ends with OP_Yield or OP_Return then continue
-** to the next instruction. But if the co-routine ends with
-** OP_EndCoroutine, jump immediately to P2.
+** If the coroutine that is launched by this instruction ends with
+** Yield or Return then continue to the next instruction. But if
+** the coroutine launched by this instruction ends with
+** EndCoroutine, then jump to P2 rather than continuing with the
+** next instruction.
+**
+** See also: InitCoroutine
*/
case OP_Yield: { /* in1, jump */
int pcDest;
/* Opcode: Once P1 P2 * * *
**
-** Check if OP_Once flag P1 is set. If so, jump to instruction P2. Otherwise,
-** set the flag and fall through to the next instruction. In other words,
-** this opcode causes all following opcodes up through P2 (but not including
-** P2) to run just once and to be skipped on subsequent times through the loop.
+** Check the "once" flag number P1. If it is set, jump to instruction P2.
+** Otherwise, set the flag and fall through to the next instruction.
+** In other words, this opcode causes all following opcodes up through P2
+** (but not including P2) to run just once and to be skipped on subsequent
+** times through the loop.
+**
+** All "once" flags are initially cleared whenever a prepared statement
+** first begins to run.
*/
case OP_Once: { /* jump */
assert( pOp->p1<p->nOnceFlag );
**
** This opcode leaves the cursor configured to move in forward order,
** from the begining toward the end. In other words, the cursor is
-** configured to use OP_Next, not OP_Prev.
+** configured to use Next, not Prev.
**
** See also: Found, NotFound, SeekLt, SeekGt, SeekLe
*/
**
** This opcode leaves the cursor configured to move in forward order,
** from the begining toward the end. In other words, the cursor is
-** configured to use OP_Next, not OP_Prev.
+** configured to use Next, not Prev.
**
** See also: Found, NotFound, SeekLt, SeekGe, SeekLe
*/
**
** This opcode leaves the cursor configured to move in reverse order,
** from the end toward the beginning. In other words, the cursor is
-** configured to use OP_Prev, not OP_Next.
+** configured to use Prev, not Next.
**
** See also: Found, NotFound, SeekGt, SeekGe, SeekLe
*/
**
** This opcode leaves the cursor configured to move in reverse order,
** from the end toward the beginning. In other words, the cursor is
-** configured to use OP_Prev, not OP_Next.
+** configured to use Prev, not Next.
**
** See also: Found, NotFound, SeekGt, SeekGe, SeekLt
*/
**
** This opcode leaves the cursor configured to move in reverse order,
** from the end toward the beginning. In other words, the cursor is
-** configured to use OP_Prev, not OP_Next.
+** configured to use Prev, not Next.
*/
case OP_Last: { /* jump */
VdbeCursor *pC;
**
** This opcode leaves the cursor configured to move in forward order,
** from the begining toward the end. In other words, the cursor is
-** configured to use OP_Next, not OP_Prev.
+** configured to use Next, not Prev.
*/
case OP_Rewind: { /* jump */
VdbeCursor *pC;
** to the following instruction. But if the cursor advance was successful,
** jump immediately to P2.
**
-** The OP_Next opcode is only valid following an OP_SeekGT, OP_SeekGE, or
-** OP_Rewind opcode used to position the cursor. OP_Next is not allowed
-** to follow OP_SeekLT, OP_SeekLE, or OP_Last.
+** The Next opcode is only valid following an SeekGT, SeekGE, or
+** OP_Rewind opcode used to position the cursor. Next is not allowed
+** to follow SeekLT, SeekLE, or OP_Last.
**
** The P1 cursor must be for a real table, not a pseudo-table. P1 must have
** been opened prior to this opcode or the program will segfault.
*/
/* Opcode: NextIfOpen P1 P2 P3 P4 P5
**
-** This opcode works just like OP_Next except that if cursor P1 is not
+** This opcode works just like Next except that if cursor P1 is not
** open it behaves a no-op.
*/
/* Opcode: Prev P1 P2 P3 P4 P5
** jump immediately to P2.
**
**
-** The OP_Prev opcode is only valid following an OP_SeekLT, OP_SeekLE, or
-** OP_Last opcode used to position the cursor. OP_Prev is not allowed
-** to follow OP_SeekGT, OP_SeekGE, or OP_Rewind.
+** The Prev opcode is only valid following an SeekLT, SeekLE, or
+** OP_Last opcode used to position the cursor. Prev is not allowed
+** to follow SeekGT, SeekGE, or OP_Rewind.
**
** The P1 cursor must be for a real table, not a pseudo-table. If P1 is
** not open then the behavior is undefined.
*/
/* Opcode: PrevIfOpen P1 P2 P3 P4 P5
**
-** This opcode works just like OP_Prev except that if cursor P1 is not
+** This opcode works just like Prev except that if cursor P1 is not
** open it behaves a no-op.
*/
case OP_SorterNext: { /* jump */
**
** Remove the internal (in-memory) data structures that describe
** the table named P4 in database P1. This is called after a table
-** is dropped in order to keep the internal representation of the
+** is dropped from disk (using the Destroy opcode) in order to keep
+** the internal representation of the
** schema consistent with what is on disk.
*/
case OP_DropTable: {
**
** Remove the internal (in-memory) data structures that describe
** the index named P4 in database P1. This is called after an index
-** is dropped in order to keep the internal representation of the
+** is dropped from disk (using the Destroy opcode)
+** in order to keep the internal representation of the
** schema consistent with what is on disk.
*/
case OP_DropIndex: {
**
** Remove the internal (in-memory) data structures that describe
** the trigger named P4 in database P1. This is called after a trigger
-** is dropped in order to keep the internal representation of the
+** is dropped from disk (using the Destroy opcode) in order to keep
+** the internal representation of the
** schema consistent with what is on disk.
*/
case OP_DropTrigger: {
projects / thirdparty / sqlite.git / commitdiff
