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Overview
Comment: | Reorder the elements of the Mem object for a small size reduction and performance improvement. Moved into a branch because MSVC is unable to handle named structure initializer on nullMem. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | micro-optimizations |
Files: | files | file ages | folders |
SHA1: |
0be3019ed794c10de67dfd645ceea7d4 |
User & Date: | drh 2014-09-16 14:16:31.846 |
Original Comment: | Reorder the elements of the Mem object for a small size reduction and performance improvement. |
Context
2014-09-16
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14:37 | Reduce the number of arguments to RecordCompare functions from 4 to 3, resulting in a small performance increase. (check-in: 8239c35aed user: drh tags: micro-optimizations) | |
14:16 | Reorder the elements of the Mem object for a small size reduction and performance improvement. Moved into a branch because MSVC is unable to handle named structure initializer on nullMem. (check-in: 0be3019ed7 user: drh tags: micro-optimizations) | |
13:30 | Changes to sqlite3VdbeRecordUnpack() to make it slightly smaller and faster. (check-in: 8fb90da77c user: drh tags: trunk) | |
Changes
Changes to src/func.c.
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1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 | cmp = sqlite3MemCompare(pBest, pArg, pColl); if( (max && cmp<0) || (!max && cmp>0) ){ sqlite3VdbeMemCopy(pBest, pArg); }else{ sqlite3SkipAccumulatorLoad(context); } }else{ sqlite3VdbeMemCopy(pBest, pArg); } } static void minMaxFinalize(sqlite3_context *context){ sqlite3_value *pRes; pRes = (sqlite3_value *)sqlite3_aggregate_context(context, 0); if( pRes ){ | > | 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 | cmp = sqlite3MemCompare(pBest, pArg, pColl); if( (max && cmp<0) || (!max && cmp>0) ){ sqlite3VdbeMemCopy(pBest, pArg); }else{ sqlite3SkipAccumulatorLoad(context); } }else{ pBest->db = sqlite3_context_db_handle(context); sqlite3VdbeMemCopy(pBest, pArg); } } static void minMaxFinalize(sqlite3_context *context){ sqlite3_value *pRes; pRes = (sqlite3_value *)sqlite3_aggregate_context(context, 0); if( pRes ){ |
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Changes to src/vdbeInt.h.
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157 158 159 160 161 162 163 | /* ** Internally, the vdbe manipulates nearly all SQL values as Mem ** structures. Each Mem struct may cache multiple representations (string, ** integer etc.) of the same value. */ struct Mem { | < < < < > > > > > > > < < | 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 | /* ** Internally, the vdbe manipulates nearly all SQL values as Mem ** structures. Each Mem struct may cache multiple representations (string, ** integer etc.) of the same value. */ struct Mem { union { i64 i; /* Integer value used when MEM_Int is set in flags */ int nZero; /* Used when bit MEM_Zero is set in flags */ FuncDef *pDef; /* Used only when flags==MEM_Agg */ RowSet *pRowSet; /* Used only when flags==MEM_RowSet */ VdbeFrame *pFrame; /* Used when flags==MEM_Frame */ } u; u16 flags; /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */ u8 enc; /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */ int n; /* Number of characters in string value, excluding '\0' */ double r; /* Real value */ char *z; /* String or BLOB value */ char *zMalloc; /* Dynamic buffer allocated by sqlite3_malloc() */ /* ShallowCopy only needs to copy the information above */ sqlite3 *db; /* The associated database connection */ void (*xDel)(void*);/* If not null, call this function to delete Mem.z */ #ifdef SQLITE_DEBUG Mem *pScopyFrom; /* This Mem is a shallow copy of pScopyFrom */ void *pFiller; /* So that sizeof(Mem) is a multiple of 8 */ #endif }; /* One or more of the following flags are set to indicate the validOK ** representations of the value stored in the Mem struct. ** ** If the MEM_Null flag is set, then the value is an SQL NULL value. ** No other flags may be set in this case. |
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Changes to src/vdbeapi.c.
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799 800 801 802 803 804 805 | ** these assert()s from failing, when building with SQLITE_DEBUG defined ** using gcc, we force nullMem to be 8-byte aligned using the magical ** __attribute__((aligned(8))) macro. */ static const Mem nullMem #if defined(SQLITE_DEBUG) && defined(__GNUC__) __attribute__((aligned(8))) #endif | > > > > | > > > > > | > | | 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 | ** these assert()s from failing, when building with SQLITE_DEBUG defined ** using gcc, we force nullMem to be 8-byte aligned using the magical ** __attribute__((aligned(8))) macro. */ static const Mem nullMem #if defined(SQLITE_DEBUG) && defined(__GNUC__) __attribute__((aligned(8))) #endif = { .flags = MEM_Null, .enc = 0, .n = 0, .r = (double)0, .u = {0}, .z = 0, .zMalloc = 0, .db = 0, .xDel = 0, #ifdef SQLITE_DEBUG .pScopyFrom = 0, .pFiller = 0, #endif }; return &nullMem; } /* ** Check to see if column iCol of the given statement is valid. If ** it is, return a pointer to the Mem for the value of that column. ** If iCol is not valid, return a pointer to a Mem which has a value |
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Changes to src/vdbeaux.c.
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3299 3300 3301 3302 3303 3304 3305 | return pColl->xCmp(pColl->pUser,pMem1->n,pMem1->z,pMem2->n,pMem2->z); }else{ int rc; const void *v1, *v2; int n1, n2; Mem c1; Mem c2; | | | > | 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 | return pColl->xCmp(pColl->pUser,pMem1->n,pMem1->z,pMem2->n,pMem2->z); }else{ int rc; const void *v1, *v2; int n1, n2; Mem c1; Mem c2; c1.db = c2.db = pMem1->db; c1.flags = c2.flags = 0; c1.zMalloc = c2.zMalloc = 0; sqlite3VdbeMemShallowCopy(&c1, pMem1, MEM_Ephem); sqlite3VdbeMemShallowCopy(&c2, pMem2, MEM_Ephem); v1 = sqlite3ValueText((sqlite3_value*)&c1, pColl->enc); n1 = v1==0 ? 0 : c1.n; v2 = sqlite3ValueText((sqlite3_value*)&c2, pColl->enc); n2 = v2==0 ? 0 : c2.n; rc = pColl->xCmp(pColl->pUser, n1, v1, n2, v2); |
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Changes to src/vdbemem.c.
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726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 | ** Make an shallow copy of pFrom into pTo. Prior contents of ** pTo are freed. The pFrom->z field is not duplicated. If ** pFrom->z is used, then pTo->z points to the same thing as pFrom->z ** and flags gets srcType (either MEM_Ephem or MEM_Static). */ void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){ assert( (pFrom->flags & MEM_RowSet)==0 ); VdbeMemReleaseExtern(pTo); memcpy(pTo, pFrom, MEMCELLSIZE); pTo->xDel = 0; if( (pFrom->flags&MEM_Static)==0 ){ pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Ephem); assert( srcType==MEM_Ephem || srcType==MEM_Static ); pTo->flags |= srcType; } } /* ** Make a full copy of pFrom into pTo. Prior contents of pTo are ** freed before the copy is made. */ int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){ int rc = SQLITE_OK; assert( (pFrom->flags & MEM_RowSet)==0 ); VdbeMemReleaseExtern(pTo); memcpy(pTo, pFrom, MEMCELLSIZE); pTo->flags &= ~MEM_Dyn; pTo->xDel = 0; if( pTo->flags&(MEM_Str|MEM_Blob) ){ | > > | 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 | ** Make an shallow copy of pFrom into pTo. Prior contents of ** pTo are freed. The pFrom->z field is not duplicated. If ** pFrom->z is used, then pTo->z points to the same thing as pFrom->z ** and flags gets srcType (either MEM_Ephem or MEM_Static). */ void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){ assert( (pFrom->flags & MEM_RowSet)==0 ); assert( pTo->db==pFrom->db ); VdbeMemReleaseExtern(pTo); memcpy(pTo, pFrom, MEMCELLSIZE); pTo->xDel = 0; if( (pFrom->flags&MEM_Static)==0 ){ pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Ephem); assert( srcType==MEM_Ephem || srcType==MEM_Static ); pTo->flags |= srcType; } } /* ** Make a full copy of pFrom into pTo. Prior contents of pTo are ** freed before the copy is made. */ int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){ int rc = SQLITE_OK; assert( pTo->db==pFrom->db ); assert( (pFrom->flags & MEM_RowSet)==0 ); VdbeMemReleaseExtern(pTo); memcpy(pTo, pFrom, MEMCELLSIZE); pTo->flags &= ~MEM_Dyn; pTo->xDel = 0; if( pTo->flags&(MEM_Str|MEM_Blob) ){ |
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