From: drh Date: Fri, 25 Jul 2014 18:37:42 +0000 (+0000) Subject: Improved comments on VDBE opcodes, for better documentation. No code X-Git-Tag: version-3.8.6~59 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5dad9a3497f47f9277c8d1562b814e9292371d0c;p=thirdparty%2Fsqlite.git Improved comments on VDBE opcodes, for better documentation. No code or logic changes. FossilOrigin-Name: 2d32e4876e0b162730f81e5c2658be12d64a9a99 --- diff --git a/manifest b/manifest index 30ae97fa3c..34fbf9cae2 100644 --- a/manifest +++ b/manifest @@ -1,5 +1,5 @@ -C Add\sconstraints\s(enforced\sonly\swhen\sSQLITE_DEBUG\sis\senabled)\son\sthe\suse\sof\nOP_Next\sand\sOP_Prev. -D 2014-07-25T18:01:06.435 +C Improved\scomments\son\sVDBE\sopcodes,\sfor\sbetter\sdocumentation.\s\sNo\scode\nor\slogic\schanges. +D 2014-07-25T18:37:42.754 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f F Makefile.in 5eb79e334a5de69c87740edd56af6527dd219308 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23 @@ -283,7 +283,7 @@ F src/update.c 01564b3c430f6c7b0a35afaf7aba7987206fa3a5 F src/utf.c a0314e637768a030e6e84a957d0c4f6ba910cc05 F src/util.c 3076bdd51cdbf60a6e2e57fada745be37133c73e F src/vacuum.c 3728d74919d4fb1356f9e9a13e27773db60b7179 -F src/vdbe.c c6a9094a56b3dd4769243051a512f89763af7de5 +F src/vdbe.c b7af861342a215c7f27d3f20d92fe0b70f54fb3e F src/vdbe.h c63fad052c9e7388d551e556e119c0bcf6bebdf8 F src/vdbeInt.h f5513f2b5ac1e2c5128996c7ea23add256a301df F src/vdbeapi.c 24e40422382beb774daab11fe9fe9d37e8a04949 @@ -1184,7 +1184,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4 F tool/warnings.sh 0abfd78ceb09b7f7c27c688c8e3fe93268a13b32 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f -P 114dcf33670fd98a1ebbac0e44f66b2d8bcccddf -R f27032fe9d592a52e4ec63c28d270176 +P 2230c74f1efa591770176c9b40e920724a3c39e1 +R 29600123a95daa5177cd67bf8abb597c U drh -Z 96714d48e7c72e5d439e8f51e5a0d88e +Z 36e2e79e107a063c258f47507608b039 diff --git a/manifest.uuid b/manifest.uuid index 9d6edd3229..a16837f979 100644 --- a/manifest.uuid +++ b/manifest.uuid @@ -1 +1 @@ -2230c74f1efa591770176c9b40e920724a3c39e1 \ No newline at end of file +2d32e4876e0b162730f81e5c2658be12d64a9a99 \ No newline at end of file diff --git a/src/vdbe.c b/src/vdbe.c index 60d8ebf3e5..e53b9251a3 100644 --- a/src/vdbe.c +++ b/src/vdbe.c @@ -767,12 +767,14 @@ case OP_Return: { /* in1 */ /* 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) ); @@ -788,9 +790,11 @@ case OP_InitCoroutine: { /* jump */ /* 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; @@ -807,11 +811,16 @@ case OP_EndCoroutine: { /* in1 */ /* 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; @@ -2196,10 +2205,14 @@ case OP_BitNot: { /* same as TK_BITNOT, in1, out2 */ /* 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->p1nOnceFlag ); @@ -3495,7 +3508,7 @@ case OP_Close: { ** ** 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 */ @@ -3513,7 +3526,7 @@ case OP_Close: { ** ** 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 */ @@ -3531,7 +3544,7 @@ case OP_Close: { ** ** 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 */ @@ -3549,7 +3562,7 @@ case OP_Close: { ** ** 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 */ @@ -4470,7 +4483,7 @@ case OP_NullRow: { ** ** 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; @@ -4530,7 +4543,7 @@ case OP_Sort: { /* jump */ ** ** 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; @@ -4571,9 +4584,9 @@ case OP_Rewind: { /* jump */ ** 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. @@ -4593,7 +4606,7 @@ case OP_Rewind: { /* jump */ */ /* 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 @@ -4604,9 +4617,9 @@ case OP_Rewind: { /* jump */ ** 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. @@ -4624,7 +4637,7 @@ case OP_Rewind: { /* jump */ */ /* 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 */ @@ -5145,7 +5158,8 @@ case OP_LoadAnalysis: { ** ** 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: { @@ -5157,7 +5171,8 @@ 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: { @@ -5169,7 +5184,8 @@ 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: {