From: drh Date: Tue, 6 Oct 2015 21:07:06 +0000 (+0000) Subject: Simplifications to the VDBE bytecode that handles LIMIT and OFFSET. X-Git-Tag: version-3.9.0~33 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=8b0cf38a12157db112d5fcd3c17074d4f8cdd84d;p=thirdparty%2Fsqlite.git Simplifications to the VDBE bytecode that handles LIMIT and OFFSET. FossilOrigin-Name: 041df7c2f14b95868a08090354ebb3308050790e --- diff --git a/manifest b/manifest index b5fce18292..3a6b97649f 100644 --- a/manifest +++ b/manifest @@ -1,5 +1,5 @@ -C Optimizations\sfor\sfts5\sexpressions\sthat\sfilter\son\scolumn.\sMore\sstill\sto\scome. -D 2015-10-06T20:53:26.753 +C Simplifications\sto\sthe\sVDBE\sbytecode\sthat\shandles\sLIMIT\sand\sOFFSET. +D 2015-10-06T21:07:06.319 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f F Makefile.in 2143eeef6d0cc26006ae5fc4bb242a4a8b973412 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23 @@ -335,14 +335,14 @@ F src/parse.y f599aa5e871a493330d567ced93de696f61f48f7 F src/pcache.c 24be750c79272e0ca7b6e007bc94999700f3e5ef F src/pcache.h 9968603796240cdf83da7e7bef76edf90619cea9 F src/pcache1.c e822007159d53a7ea7aa040d6e28964ddb6de083 -F src/pragma.c 234814978bcd35bce6e2874dfb2f5b5e28e7fb38 +F src/pragma.c dcfe3a35d2de935feeaba1455528b4a5c4f1208c F src/pragma.h 631a91c8b0e6ca8f051a1d8a4a0da4150e04620a F src/prepare.c 82e5db1013846a819f198336fed72c44c974e7b1 F src/printf.c 0c4bcdd1c2e2521024f0a69cb5eb334f86b3652a F src/random.c ba2679f80ec82c4190062d756f22d0c358180696 F src/resolve.c 1954a0f01bf65d78d7d559aea3d5c67f33376d91 F src/rowset.c eccf6af6d620aaa4579bd3b72c1b6395d9e9fa1e -F src/select.c 8fb8cb0230aed9b12b3582ddc366ffbc549041d7 +F src/select.c 2c4bfdf7c797df9b43121ed7850bf939b6f27405 F src/shell.c dfd18e56fcb88dd79378774e9bc3246a9bd52243 F src/sqlite.h.in 4b76d74d69af48c534c58fb723137dc6944bdedc F src/sqlite3.rc 992c9f5fb8285ae285d6be28240a7e8d3a7f2bad @@ -405,7 +405,7 @@ F src/update.c a134027f59c7eb6e63ed18e2d5dd8ef0ce7f8ff8 F src/utf.c fc6b889ba0779b7722634cdeaa25f1930d93820c F src/util.c fc612367108b74573c5fd13a85d0a23027f438bd F src/vacuum.c 2ddd5cad2a7b9cef7f9e431b8c7771634c6b1701 -F src/vdbe.c 5048103aa6bc9c01bf1a4620729256d1e873bb6c +F src/vdbe.c d263ec6b29d8e8e8178235b8403a00ccb48748d0 F src/vdbe.h 4bc88bd0e06f8046ee6ab7487c0015e85ad949ad F src/vdbeInt.h 8b867eac234e28627ffcace3cd4b4b79bbec664b F src/vdbeapi.c 020681b943e77766b32ae1cddf86d7831b7374ca @@ -1392,7 +1392,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4 F tool/warnings.sh 48bd54594752d5be3337f12c72f28d2080cb630b F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f -P 4b631364354068af95a01630469cb6fbfe8b52fd -R 8d25a208807a117d422df371476abd9e -U dan -Z f7ba9c7b6fd75653c93e200489a4e473 +P bf1607ac155018573ca40fb58aca62c5fea7e60b +R f75f4370adf88bb173a9ed2d414ba858 +U drh +Z 3f5b7bfbaf5afcf9be7e111589aea155 diff --git a/manifest.uuid b/manifest.uuid index 709fd4d260..9a61b499bb 100644 --- a/manifest.uuid +++ b/manifest.uuid @@ -1 +1 @@ -bf1607ac155018573ca40fb58aca62c5fea7e60b \ No newline at end of file +041df7c2f14b95868a08090354ebb3308050790e \ No newline at end of file diff --git a/src/pragma.c b/src/pragma.c index e5e7e54a29..64614a7ebc 100644 --- a/src/pragma.c +++ b/src/pragma.c @@ -1361,8 +1361,9 @@ void sqlite3Pragma( */ static const int iLn = VDBE_OFFSET_LINENO(2); static const VdbeOpList endCode[] = { - { OP_IfNeg, 1, 0, 0}, /* 0 */ - { OP_String8, 0, 3, 0}, /* 1 */ + { OP_AddImm, 1, 0, 0}, /* 0 */ + { OP_If, 1, 0, 0}, /* 1 */ + { OP_String8, 0, 3, 0}, /* 2 */ { OP_ResultRow, 3, 1, 0}, }; @@ -1563,9 +1564,9 @@ void sqlite3Pragma( } } addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode, iLn); - sqlite3VdbeChangeP3(v, addr, -mxErr); - sqlite3VdbeJumpHere(v, addr); - sqlite3VdbeChangeP4(v, addr+1, "ok", P4_STATIC); + sqlite3VdbeChangeP2(v, addr, -mxErr); + sqlite3VdbeJumpHere(v, addr+1); + sqlite3VdbeChangeP4(v, addr+2, "ok", P4_STATIC); } break; #endif /* SQLITE_OMIT_INTEGRITY_CHECK */ diff --git a/src/select.c b/src/select.c index c6c722cbc5..548030fb14 100644 --- a/src/select.c +++ b/src/select.c @@ -579,7 +579,7 @@ static void pushOntoSorter( }else{ iLimit = pSelect->iLimit; } - addr = sqlite3VdbeAddOp3(v, OP_IfNotZero, iLimit, 0, -1); VdbeCoverage(v); + addr = sqlite3VdbeAddOp3(v, OP_IfNotZero, iLimit, 0, 1); VdbeCoverage(v); sqlite3VdbeAddOp1(v, OP_Last, pSort->iECursor); sqlite3VdbeAddOp1(v, OP_Delete, pSort->iECursor); sqlite3VdbeJumpHere(v, addr); @@ -595,11 +595,8 @@ static void codeOffset( int iContinue /* Jump here to skip the current record */ ){ if( iOffset>0 ){ - int addr; - addr = sqlite3VdbeAddOp3(v, OP_IfNeg, iOffset, 0, -1); VdbeCoverage(v); - sqlite3VdbeGoto(v, iContinue); - VdbeComment((v, "skip OFFSET records")); - sqlite3VdbeJumpHere(v, addr); + sqlite3VdbeAddOp3(v, OP_IfPos, iOffset, iContinue, 1); VdbeCoverage(v); + VdbeComment((v, "OFFSET")); } } @@ -1815,7 +1812,7 @@ static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){ Vdbe *v = 0; int iLimit = 0; int iOffset; - int addr1, n; + int n; if( p->iLimit ) return; /* @@ -1850,14 +1847,10 @@ static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){ sqlite3ExprCode(pParse, p->pOffset, iOffset); sqlite3VdbeAddOp1(v, OP_MustBeInt, iOffset); VdbeCoverage(v); VdbeComment((v, "OFFSET counter")); - addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iOffset); VdbeCoverage(v); - sqlite3VdbeAddOp2(v, OP_Integer, 0, iOffset); - sqlite3VdbeJumpHere(v, addr1); + sqlite3VdbeAddOp3(v, OP_SetIfNotPos, iOffset, iOffset, 0); sqlite3VdbeAddOp3(v, OP_Add, iLimit, iOffset, iOffset+1); VdbeComment((v, "LIMIT+OFFSET")); - addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iLimit); VdbeCoverage(v); - sqlite3VdbeAddOp2(v, OP_Integer, -1, iOffset+1); - sqlite3VdbeJumpHere(v, addr1); + sqlite3VdbeAddOp3(v, OP_SetIfNotPos, iLimit, iOffset+1, -1); } } } @@ -2274,14 +2267,9 @@ static int multiSelect( addr = sqlite3VdbeAddOp1(v, OP_IfNot, p->iLimit); VdbeCoverage(v); VdbeComment((v, "Jump ahead if LIMIT reached")); if( p->iOffset ){ - int addr2; + sqlite3VdbeAddOp3(v, OP_SetIfNotPos, p->iOffset, p->iOffset, 0); sqlite3VdbeAddOp3(v, OP_Add, p->iLimit, p->iOffset, p->iOffset+1); - addr2 = sqlite3VdbeAddOp1(v, OP_IfPos, p->iOffset); VdbeCoverage(v); - sqlite3VdbeAddOp2(v, OP_SCopy, p->iLimit, p->iOffset+1); - sqlite3VdbeJumpHere(v, addr2); - addr2 = sqlite3VdbeAddOp1(v, OP_IfPos, p->iLimit); VdbeCoverage(v); - sqlite3VdbeAddOp2(v, OP_Integer, -1, p->iOffset+1); - sqlite3VdbeJumpHere(v, addr2); + sqlite3VdbeAddOp3(v, OP_SetIfNotPos, p->iLimit, p->iOffset+1, -1); } } explainSetInteger(iSub2, pParse->iNextSelectId); diff --git a/src/vdbe.c b/src/vdbe.c index 23338879c5..6dfe52c4eb 100644 --- a/src/vdbe.c +++ b/src/vdbe.c @@ -5671,12 +5671,12 @@ case OP_MemMax: { /* in2 */ } #endif /* SQLITE_OMIT_AUTOINCREMENT */ -/* Opcode: IfPos P1 P2 * * * -** Synopsis: if r[P1]>0 goto P2 +/* Opcode: IfPos P1 P2 P3 * * +** Synopsis: if r[P1]>0 then r[P1]-=P3, goto P2 ** ** Register P1 must contain an integer. -** If the value of register P1 is 1 or greater, jump to P2 and -** add the literal value P3 to register P1. +** If the value of register P1 is 1 or greater, subtrace P3 from the +** value in P1 and jump to P2. ** ** If the initial value of register P1 is less than 1, then the ** value is unchanged and control passes through to the next instruction. @@ -5685,38 +5685,44 @@ case OP_IfPos: { /* jump, in1 */ pIn1 = &aMem[pOp->p1]; assert( pIn1->flags&MEM_Int ); VdbeBranchTaken( pIn1->u.i>0, 2); - if( pIn1->u.i>0 ) goto jump_to_p2; + if( pIn1->u.i>0 ){ + pIn1->u.i -= pOp->p3; + goto jump_to_p2; + } break; } -/* Opcode: IfNeg P1 P2 P3 * * -** Synopsis: r[P1]+=P3, if r[P1]<0 goto P2 +/* Opcode: SetIfNotPos P1 P2 P3 * * +** Synopsis: if r[P1]<=0 then r[P2]=P3 ** -** Register P1 must contain an integer. Add literal P3 to the value in -** register P1 then if the value of register P1 is less than zero, jump to P2. +** Register P1 must contain an integer. +** If the value of register P1 is not positive (if it is less than 1) then +** set the value of register P2 to be the integer P3. */ -case OP_IfNeg: { /* jump, in1 */ +case OP_SetIfNotPos: { /* in1, in2 */ pIn1 = &aMem[pOp->p1]; assert( pIn1->flags&MEM_Int ); - pIn1->u.i += pOp->p3; - VdbeBranchTaken(pIn1->u.i<0, 2); - if( pIn1->u.i<0 ) goto jump_to_p2; + if( pIn1->u.i<=0 ){ + pOut = out2Prerelease(p, pOp); + pOut->u.i = pOp->p3; + } break; } /* Opcode: IfNotZero P1 P2 P3 * * -** Synopsis: if r[P1]!=0 then r[P1]+=P3, goto P2 +** Synopsis: if r[P1]!=0 then r[P1]-=P3, goto P2 ** ** Register P1 must contain an integer. If the content of register P1 is -** initially nonzero, then add P3 to P1 and jump to P2. If register P1 is -** initially zero, leave it unchanged and fall through. +** initially nonzero, then subtrace P3 from the value in register P1 and +** jump to P2. If register P1 is initially zero, leave it unchanged +** and fall through. */ case OP_IfNotZero: { /* jump, in1 */ pIn1 = &aMem[pOp->p1]; assert( pIn1->flags&MEM_Int ); VdbeBranchTaken(pIn1->u.i<0, 2); if( pIn1->u.i ){ - pIn1->u.i += pOp->p3; + pIn1->u.i -= pOp->p3; goto jump_to_p2; } break;