mattercontrol/Community.CsharpSqlite/src/expr_c.cs
2015-04-08 15:20:10 -07:00

4547 lines
No EOL
137 KiB
C#

#define SQLITE_MAX_EXPR_DEPTH
using System;
using System.Diagnostics;
using i64 = System.Int64;
using u8 = System.Byte;
using u32 = System.UInt32;
using u16 = System.UInt16;
#if !SQLITE_MAX_VARIABLE_NUMBER
using ynVar = System.Int16;
#else
using ynVar = System.Int32;
#endif
namespace Community.CsharpSqlite
{
public partial class Sqlite3
{
/*
** 2001 September 15
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
*************************************************************************
** Included in SQLite3 port to C#-SQLite; 2008 Noah B Hart
** C#-SQLite is an independent reimplementation of the SQLite software library
**
** SQLITE_SOURCE_ID: 2011-06-23 19:49:22 4374b7e83ea0a3fbc3691f9c0c936272862f32f2
**
*************************************************************************
*/
//#include "sqliteInt.h"
/*
** Return the 'affinity' of the expression pExpr if any.
**
** If pExpr is a column, a reference to a column via an 'AS' alias,
** or a sub-select with a column as the return value, then the
** affinity of that column is returned. Otherwise, 0x00 is returned,
** indicating no affinity for the expression.
**
** i.e. the WHERE clause expresssions in the following statements all
** have an affinity:
**
** CREATE TABLE t1(a);
** SELECT * FROM t1 WHERE a;
** SELECT a AS b FROM t1 WHERE b;
** SELECT * FROM t1 WHERE (select a from t1);
*/
private static char sqlite3ExprAffinity(Expr pExpr)
{
int op = pExpr.op;
if (op == TK_SELECT)
{
Debug.Assert((pExpr.flags & EP_xIsSelect) != 0);
return sqlite3ExprAffinity(pExpr.x.pSelect.pEList.a[0].pExpr);
}
#if !SQLITE_OMIT_CAST
if (op == TK_CAST)
{
Debug.Assert(!ExprHasProperty(pExpr, EP_IntValue));
return sqlite3AffinityType(pExpr.u.zToken);
}
#endif
if ((op == TK_AGG_COLUMN || op == TK_COLUMN || op == TK_REGISTER)
&& pExpr.pTab != null
)
{
/* op==TK_REGISTER && pExpr.pTab!=0 happens when pExpr was originally
** a TK_COLUMN but was previously evaluated and cached in a register */
int j = pExpr.iColumn;
if (j < 0)
return SQLITE_AFF_INTEGER;
Debug.Assert(pExpr.pTab != null && j < pExpr.pTab.nCol);
return pExpr.pTab.aCol[j].affinity;
}
return pExpr.affinity;
}
/*
** Set the explicit collating sequence for an expression to the
** collating sequence supplied in the second argument.
*/
private static Expr sqlite3ExprSetColl(Expr pExpr, CollSeq pColl)
{
if (pExpr != null && pColl != null)
{
pExpr.pColl = pColl;
pExpr.flags |= EP_ExpCollate;
}
return pExpr;
}
/*
** Set the collating sequence for expression pExpr to be the collating
** sequence named by pToken. Return a pointer to the revised expression.
** The collating sequence is marked as "explicit" using the EP_ExpCollate
** flag. An explicit collating sequence will override implicit
** collating sequences.
*/
private static Expr sqlite3ExprSetCollByToken(Parse pParse, Expr pExpr, Token pCollName)
{
string zColl; /* Dequoted name of collation sequence */
CollSeq pColl;
sqlite3 db = pParse.db;
zColl = sqlite3NameFromToken(db, pCollName);
pColl = sqlite3LocateCollSeq(pParse, zColl);
sqlite3ExprSetColl(pExpr, pColl);
sqlite3DbFree(db, ref zColl);
return pExpr;
}
/*
** Return the default collation sequence for the expression pExpr. If
** there is no default collation type, return 0.
*/
private static CollSeq sqlite3ExprCollSeq(Parse pParse, Expr pExpr)
{
CollSeq pColl = null;
Expr p = pExpr;
while (ALWAYS(p))
{
int op;
pColl = pExpr.pColl;
if (pColl != null)
break;
op = p.op;
if (p.pTab != null && (
op == TK_AGG_COLUMN || op == TK_COLUMN || op == TK_REGISTER || op == TK_TRIGGER
))
{
/* op==TK_REGISTER && p->pTab!=0 happens when pExpr was originally
** a TK_COLUMN but was previously evaluated and cached in a register */
string zColl;
int j = p.iColumn;
if (j >= 0)
{
sqlite3 db = pParse.db;
zColl = p.pTab.aCol[j].zColl;
pColl = sqlite3FindCollSeq(db, ENC(db), zColl, 0);
pExpr.pColl = pColl;
}
break;
}
if (op != TK_CAST && op != TK_UPLUS)
{
break;
}
p = p.pLeft;
}
if (sqlite3CheckCollSeq(pParse, pColl) != 0)
{
pColl = null;
}
return pColl;
}
/*
** pExpr is an operand of a comparison operator. aff2 is the
** type affinity of the other operand. This routine returns the
** type affinity that should be used for the comparison operator.
*/
private static char sqlite3CompareAffinity(Expr pExpr, char aff2)
{
char aff1 = sqlite3ExprAffinity(pExpr);
if (aff1 != '\0' && aff2 != '\0')
{
/* Both sides of the comparison are columns. If one has numeric
** affinity, use that. Otherwise use no affinity.
*/
if (aff1 >= SQLITE_AFF_NUMERIC || aff2 >= SQLITE_AFF_NUMERIC)
// if (sqlite3IsNumericAffinity(aff1) || sqlite3IsNumericAffinity(aff2))
{
return SQLITE_AFF_NUMERIC;
}
else
{
return SQLITE_AFF_NONE;
}
}
else if (aff1 == '\0' && aff2 == '\0')
{
/* Neither side of the comparison is a column. Compare the
** results directly.
*/
return SQLITE_AFF_NONE;
}
else
{
/* One side is a column, the other is not. Use the columns affinity. */
Debug.Assert(aff1 == 0 || aff2 == 0);
return (aff1 != '\0' ? aff1 : aff2);
}
}
/*
** pExpr is a comparison operator. Return the type affinity that should
** be applied to both operands prior to doing the comparison.
*/
private static char comparisonAffinity(Expr pExpr)
{
char aff;
Debug.Assert(pExpr.op == TK_EQ || pExpr.op == TK_IN || pExpr.op == TK_LT ||
pExpr.op == TK_GT || pExpr.op == TK_GE || pExpr.op == TK_LE ||
pExpr.op == TK_NE || pExpr.op == TK_IS || pExpr.op == TK_ISNOT);
Debug.Assert(pExpr.pLeft != null);
aff = sqlite3ExprAffinity(pExpr.pLeft);
if (pExpr.pRight != null)
{
aff = sqlite3CompareAffinity(pExpr.pRight, aff);
}
else if (ExprHasProperty(pExpr, EP_xIsSelect))
{
aff = sqlite3CompareAffinity(pExpr.x.pSelect.pEList.a[0].pExpr, aff);
}
else if (aff == '\0')
{
aff = SQLITE_AFF_NONE;
}
return aff;
}
/*
** pExpr is a comparison expression, eg. '=', '<', IN(...) etc.
** idx_affinity is the affinity of an indexed column. Return true
** if the index with affinity idx_affinity may be used to implement
** the comparison in pExpr.
*/
private static bool sqlite3IndexAffinityOk(Expr pExpr, char idx_affinity)
{
char aff = comparisonAffinity(pExpr);
switch (aff)
{
case SQLITE_AFF_NONE:
return true;
case SQLITE_AFF_TEXT:
return idx_affinity == SQLITE_AFF_TEXT;
default:
return idx_affinity >= SQLITE_AFF_NUMERIC;// sqlite3IsNumericAffinity(idx_affinity);
}
}
/*
** Return the P5 value that should be used for a binary comparison
** opcode (OP_Eq, OP_Ge etc.) used to compare pExpr1 and pExpr2.
*/
private static u8 binaryCompareP5(Expr pExpr1, Expr pExpr2, int jumpIfNull)
{
u8 aff = (u8)sqlite3ExprAffinity(pExpr2);
aff = (u8)((u8)sqlite3CompareAffinity(pExpr1, (char)aff) | (u8)jumpIfNull);
return aff;
}
/*
** Return a pointer to the collation sequence that should be used by
** a binary comparison operator comparing pLeft and pRight.
**
** If the left hand expression has a collating sequence type, then it is
** used. Otherwise the collation sequence for the right hand expression
** is used, or the default (BINARY) if neither expression has a collating
** type.
**
** Argument pRight (but not pLeft) may be a null pointer. In this case,
** it is not considered.
*/
private static CollSeq sqlite3BinaryCompareCollSeq(
Parse pParse,
Expr pLeft,
Expr pRight
)
{
CollSeq pColl;
Debug.Assert(pLeft != null);
if ((pLeft.flags & EP_ExpCollate) != 0)
{
Debug.Assert(pLeft.pColl != null);
pColl = pLeft.pColl;
}
else if (pRight != null && ((pRight.flags & EP_ExpCollate) != 0))
{
Debug.Assert(pRight.pColl != null);
pColl = pRight.pColl;
}
else
{
pColl = sqlite3ExprCollSeq(pParse, pLeft);
if (pColl == null)
{
pColl = sqlite3ExprCollSeq(pParse, pRight);
}
}
return pColl;
}
/*
** Generate code for a comparison operator.
*/
private static int codeCompare(
Parse pParse, /* The parsing (and code generating) context */
Expr pLeft, /* The left operand */
Expr pRight, /* The right operand */
int opcode, /* The comparison opcode */
int in1, int in2, /* Register holding operands */
int dest, /* Jump here if true. */
int jumpIfNull /* If true, jump if either operand is NULL */
)
{
int p5;
int addr;
CollSeq p4;
p4 = sqlite3BinaryCompareCollSeq(pParse, pLeft, pRight);
p5 = binaryCompareP5(pLeft, pRight, jumpIfNull);
addr = sqlite3VdbeAddOp4(pParse.pVdbe, opcode, in2, dest, in1,
p4, P4_COLLSEQ);
sqlite3VdbeChangeP5(pParse.pVdbe, (u8)p5);
return addr;
}
#if SQLITE_MAX_EXPR_DEPTH //>0
/*
** Check that argument nHeight is less than or equal to the maximum
** expression depth allowed. If it is not, leave an error message in
** pParse.
*/
private static int sqlite3ExprCheckHeight(Parse pParse, int nHeight)
{
int rc = SQLITE_OK;
int mxHeight = pParse.db.aLimit[SQLITE_LIMIT_EXPR_DEPTH];
if (nHeight > mxHeight)
{
sqlite3ErrorMsg(pParse,
"Expression tree is too large (maximum depth %d)", mxHeight
);
rc = SQLITE_ERROR;
}
return rc;
}
/* The following three functions, heightOfExpr(), heightOfExprList()
** and heightOfSelect(), are used to determine the maximum height
** of any expression tree referenced by the structure passed as the
** first argument.
**
** If this maximum height is greater than the current value pointed
** to by pnHeight, the second parameter, then set pnHeight to that
** value.
*/
private static void heightOfExpr(Expr p, ref int pnHeight)
{
if (p != null)
{
if (p.nHeight > pnHeight)
{
pnHeight = p.nHeight;
}
}
}
private static void heightOfExprList(ExprList p, ref int pnHeight)
{
if (p != null)
{
int i;
for (i = 0; i < p.nExpr; i++)
{
heightOfExpr(p.a[i].pExpr, ref pnHeight);
}
}
}
private static void heightOfSelect(Select p, ref int pnHeight)
{
if (p != null)
{
heightOfExpr(p.pWhere, ref pnHeight);
heightOfExpr(p.pHaving, ref pnHeight);
heightOfExpr(p.pLimit, ref pnHeight);
heightOfExpr(p.pOffset, ref pnHeight);
heightOfExprList(p.pEList, ref pnHeight);
heightOfExprList(p.pGroupBy, ref pnHeight);
heightOfExprList(p.pOrderBy, ref pnHeight);
heightOfSelect(p.pPrior, ref pnHeight);
}
}
/*
** Set the Expr.nHeight variable in the structure passed as an
** argument. An expression with no children, Expr.x.pList or
** Expr.x.pSelect member has a height of 1. Any other expression
** has a height equal to the maximum height of any other
** referenced Expr plus one.
*/
private static void exprSetHeight(Expr p)
{
int nHeight = 0;
heightOfExpr(p.pLeft, ref nHeight);
heightOfExpr(p.pRight, ref nHeight);
if (ExprHasProperty(p, EP_xIsSelect))
{
heightOfSelect(p.x.pSelect, ref nHeight);
}
else
{
heightOfExprList(p.x.pList, ref nHeight);
}
p.nHeight = nHeight + 1;
}
/*
** Set the Expr.nHeight variable using the exprSetHeight() function. If
** the height is greater than the maximum allowed expression depth,
** leave an error in pParse.
*/
private static void sqlite3ExprSetHeight(Parse pParse, Expr p)
{
exprSetHeight(p);
sqlite3ExprCheckHeight(pParse, p.nHeight);
}
/*
** Return the maximum height of any expression tree referenced
** by the select statement passed as an argument.
*/
private static int sqlite3SelectExprHeight(Select p)
{
int nHeight = 0;
heightOfSelect(p, ref nHeight);
return nHeight;
}
#else
//#define exprSetHeight(y)
#endif //* SQLITE_MAX_EXPR_DEPTH>0 */
/*
** This routine is the core allocator for Expr nodes.
**
** Construct a new expression node and return a pointer to it. Memory
** for this node and for the pToken argument is a single allocation
** obtained from sqlite3DbMalloc(). The calling function
** is responsible for making sure the node eventually gets freed.
**
** If dequote is true, then the token (if it exists) is dequoted.
** If dequote is false, no dequoting is performance. The deQuote
** parameter is ignored if pToken is NULL or if the token does not
** appear to be quoted. If the quotes were of the form "..." (double-quotes)
** then the EP_DblQuoted flag is set on the expression node.
**
** Special case: If op==TK_INTEGER and pToken points to a string that
** can be translated into a 32-bit integer, then the token is not
** stored in u.zToken. Instead, the integer values is written
** into u.iValue and the EP_IntValue flag is set. No extra storage
** is allocated to hold the integer text and the dequote flag is ignored.
*/
private static Expr sqlite3ExprAlloc(
sqlite3 db, /* Handle for sqlite3DbMallocZero() (may be null) */
int op, /* Expression opcode */
Token pToken, /* Token argument. Might be NULL */
int dequote /* True to dequote */
)
{
Expr pNew;
int nExtra = 0;
int iValue = 0;
if (pToken != null)
{
if (op != TK_INTEGER || pToken.z == null || pToken.z.Length == 0
|| sqlite3GetInt32(pToken.z.ToString(), ref iValue) == false)
{
nExtra = pToken.n + 1;
Debug.Assert(iValue >= 0);
}
}
pNew = new Expr();//sqlite3DbMallocZero(db, sizeof(Expr)+nExtra);
if (pNew != null)
{
pNew.op = (u8)op;
pNew.iAgg = -1;
if (pToken != null)
{
if (nExtra == 0)
{
pNew.flags |= EP_IntValue;
pNew.u.iValue = iValue;
}
else
{
int c;
//pNew.u.zToken = (char)&pNew[1];
if (pToken.n > 0)
pNew.u.zToken = pToken.z.Substring(0, pToken.n);//memcpy(pNew.u.zToken, pToken.z, pToken.n);
else if (pToken.n == 0 && string.IsNullOrEmpty(pToken.z))
pNew.u.zToken = string.Empty;
//pNew.u.zToken[pToken.n] = 0;
if (dequote != 0 && nExtra >= 3
&& ((c = pToken.z[0]) == '\'' || c == '"' || c == '[' || c == '`'))
{
#if DEBUG_CLASS_EXPR || DEBUG_CLASS_ALL
sqlite3Dequote(ref pNew.u._zToken);
#else
sqlite3Dequote(ref pNew.u.zToken);
#endif
if (c == '"')
pNew.flags |= EP_DblQuoted;
}
}
}
#if SQLITE_MAX_EXPR_DEPTH//>0
pNew.nHeight = 1;
#endif
}
return pNew;
}
/*
** Allocate a new expression node from a zero-terminated token that has
** already been dequoted.
*/
private static Expr sqlite3Expr(
sqlite3 db, /* Handle for sqlite3DbMallocZero() (may be null) */
int op, /* Expression opcode */
string zToken /* Token argument. Might be NULL */
)
{
Token x = new Token();
x.z = zToken;
x.n = !string.IsNullOrEmpty(zToken) ? sqlite3Strlen30(zToken) : 0;
return sqlite3ExprAlloc(db, op, x, 0);
}
/*
** Attach subtrees pLeft and pRight to the Expr node pRoot.
**
** If pRoot==NULL that means that a memory allocation error has occurred.
** In that case, delete the subtrees pLeft and pRight.
*/
private static void sqlite3ExprAttachSubtrees(
sqlite3 db,
Expr pRoot,
Expr pLeft,
Expr pRight
)
{
if (pRoot == null)
{
//Debug.Assert( db.mallocFailed != 0 );
sqlite3ExprDelete(db, ref pLeft);
sqlite3ExprDelete(db, ref pRight);
}
else
{
if (pRight != null)
{
pRoot.pRight = pRight;
if ((pRight.flags & EP_ExpCollate) != 0)
{
pRoot.flags |= EP_ExpCollate;
pRoot.pColl = pRight.pColl;
}
}
if (pLeft != null)
{
pRoot.pLeft = pLeft;
if ((pLeft.flags & EP_ExpCollate) != 0)
{
pRoot.flags |= EP_ExpCollate;
pRoot.pColl = pLeft.pColl;
}
}
exprSetHeight(pRoot);
}
}
/*
** Allocate a Expr node which joins as many as two subtrees.
**
** One or both of the subtrees can be NULL. Return a pointer to the new
** Expr node. Or, if an OOM error occurs, set pParse->db->mallocFailed,
** free the subtrees and return NULL.
*/
// OVERLOADS, so I don't need to rewrite parse.c
private static Expr sqlite3PExpr(Parse pParse, int op, int null_3, int null_4, int null_5)
{
return sqlite3PExpr(pParse, op, null, null, null);
}
private static Expr sqlite3PExpr(Parse pParse, int op, int null_3, int null_4, Token pToken)
{
return sqlite3PExpr(pParse, op, null, null, pToken);
}
private static Expr sqlite3PExpr(Parse pParse, int op, Expr pLeft, int null_4, int null_5)
{
return sqlite3PExpr(pParse, op, pLeft, null, null);
}
private static Expr sqlite3PExpr(Parse pParse, int op, Expr pLeft, int null_4, Token pToken)
{
return sqlite3PExpr(pParse, op, pLeft, null, pToken);
}
private static Expr sqlite3PExpr(Parse pParse, int op, Expr pLeft, Expr pRight, int null_5)
{
return sqlite3PExpr(pParse, op, pLeft, pRight, null);
}
private static Expr sqlite3PExpr(
Parse pParse, /* Parsing context */
int op, /* Expression opcode */
Expr pLeft, /* Left operand */
Expr pRight, /* Right operand */
Token pToken /* Argument Token */
)
{
Expr p = sqlite3ExprAlloc(pParse.db, op, pToken, 1);
sqlite3ExprAttachSubtrees(pParse.db, p, pLeft, pRight);
if (p != null)
{
sqlite3ExprCheckHeight(pParse, p.nHeight);
}
return p;
}
/*
** Join two expressions using an AND operator. If either expression is
** NULL, then just return the other expression.
*/
private static Expr sqlite3ExprAnd(sqlite3 db, Expr pLeft, Expr pRight)
{
if (pLeft == null)
{
return pRight;
}
else if (pRight == null)
{
return pLeft;
}
else
{
Expr pNew = sqlite3ExprAlloc(db, TK_AND, null, 0);
sqlite3ExprAttachSubtrees(db, pNew, pLeft, pRight);
return pNew;
}
}
/*
** Construct a new expression node for a function with multiple
** arguments.
*/
// OVERLOADS, so I don't need to rewrite parse.c
private static Expr sqlite3ExprFunction(Parse pParse, int null_2, Token pToken)
{
return sqlite3ExprFunction(pParse, null, pToken);
}
private static Expr sqlite3ExprFunction(Parse pParse, ExprList pList, int null_3)
{
return sqlite3ExprFunction(pParse, pList, null);
}
private static Expr sqlite3ExprFunction(Parse pParse, ExprList pList, Token pToken)
{
Expr pNew;
sqlite3 db = pParse.db;
Debug.Assert(pToken != null);
pNew = sqlite3ExprAlloc(db, TK_FUNCTION, pToken, 1);
if (pNew == null)
{
sqlite3ExprListDelete(db, ref pList); /* Avoid memory leak when malloc fails */
return null;
}
pNew.x.pList = pList;
Debug.Assert(!ExprHasProperty(pNew, EP_xIsSelect));
sqlite3ExprSetHeight(pParse, pNew);
return pNew;
}
/*
** Assign a variable number to an expression that encodes a wildcard
** in the original SQL statement.
**
** Wildcards consisting of a single "?" are assigned the next sequential
** variable number.
**
** Wildcards of the form "?nnn" are assigned the number "nnn". We make
** sure "nnn" is not too be to avoid a denial of service attack when
** the SQL statement comes from an external source.
**
** Wildcards of the form ":aaa", "@aaa" or "$aaa" are assigned the same number
** as the previous instance of the same wildcard. Or if this is the first
** instance of the wildcard, the next sequenial variable number is
** assigned.
*/
private static void sqlite3ExprAssignVarNumber(Parse pParse, Expr pExpr)
{
sqlite3 db = pParse.db;
string z;
if (pExpr == null)
return;
Debug.Assert(!ExprHasAnyProperty(pExpr, EP_IntValue | EP_Reduced | EP_TokenOnly));
z = pExpr.u.zToken;
Debug.Assert(z != null);
Debug.Assert(z.Length != 0);
if (z.Length == 1)
{
/* Wildcard of the form "?". Assign the next variable number */
Debug.Assert(z[0] == '?');
pExpr.iColumn = (ynVar)(++pParse.nVar);
}
else
{
ynVar x = 0;
int n = sqlite3Strlen30(z);
if (z[0] == '?')
{
/* Wildcard of the form "?nnn". Convert "nnn" to an integer and
** use it as the variable number */
i64 i = 0;
bool bOk = 0 == sqlite3Atoi64(z.Substring(1), ref i, n - 1, SQLITE_UTF8);
pExpr.iColumn = x = (ynVar)i;
testcase(i == 0);
testcase(i == 1);
testcase(i == db.aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] - 1);
testcase(i == db.aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
if (bOk == false || i < 1 || i > db.aLimit[SQLITE_LIMIT_VARIABLE_NUMBER])
{
sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
db.aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
x = 0;
}
if (i > pParse.nVar)
{
pParse.nVar = (int)i;
}
}
else
{
/* Wildcards like ":aaa", "$aaa" or "@aaa". Reuse the same variable
** number as the prior appearance of the same name, or if the name
** has never appeared before, reuse the same variable number
*/
ynVar i;
for (i = 0; i < pParse.nzVar; i++)
{
if (pParse.azVar[i] != null && z.CompareTo(pParse.azVar[i]) == 0) //memcmp(pParse.azVar[i],z,n+1)==0 )
{
pExpr.iColumn = x = (ynVar)(i + 1);
break;
}
}
if (x == 0) x = pExpr.iColumn = (ynVar)(++pParse.nVar);
}
if (x > 0)
{
if (x > pParse.nzVar)
{
//char **a;
//a = sqlite3DbRealloc(db, pParse.azVar, x*sizeof(a[0]));
//if( a==0 ) return; /* Error reported through db.mallocFailed */
//pParse.azVar = a;
//memset(&a[pParse.nzVar], 0, (x-pParse.nzVar)*sizeof(a[0]));
Array.Resize(ref pParse.azVar, x);
pParse.nzVar = x;
}
if (z[0] != '?' || pParse.azVar[x - 1] == null)
{
//sqlite3DbFree(db, pParse.azVar[x-1]);
pParse.azVar[x - 1] = z.Substring(0, n);//sqlite3DbStrNDup( db, z, n );
}
}
}
if (pParse.nErr == 0 && pParse.nVar > db.aLimit[SQLITE_LIMIT_VARIABLE_NUMBER])
{
sqlite3ErrorMsg(pParse, "too many SQL variables");
}
}
/*
** Recursively delete an expression tree.
*/
private static void sqlite3ExprDelete(sqlite3 db, ref Expr p)
{
if (p == null)
return;
/* Sanity check: Assert that the IntValue is non-negative if it exists */
Debug.Assert(!ExprHasProperty(p, EP_IntValue) || p.u.iValue >= 0);
if (!ExprHasAnyProperty(p, EP_TokenOnly))
{
sqlite3ExprDelete(db, ref p.pLeft);
sqlite3ExprDelete(db, ref p.pRight);
if (!ExprHasProperty(p, EP_Reduced) && (p.flags2 & EP2_MallocedToken) != 0)
{
#if DEBUG_CLASS_EXPR || DEBUG_CLASS_ALL
sqlite3DbFree( db, ref p.u._zToken );
#else
sqlite3DbFree(db, ref p.u.zToken);
#endif
}
if (ExprHasProperty(p, EP_xIsSelect))
{
sqlite3SelectDelete(db, ref p.x.pSelect);
}
else
{
sqlite3ExprListDelete(db, ref p.x.pList);
}
}
if (!ExprHasProperty(p, EP_Static))
{
sqlite3DbFree(db, ref p);
}
}
/*
** Return the number of bytes allocated for the expression structure
** passed as the first argument. This is always one of EXPR_FULLSIZE,
** EXPR_REDUCEDSIZE or EXPR_TOKENONLYSIZE.
*/
private static int exprStructSize(Expr p)
{
if (ExprHasProperty(p, EP_TokenOnly))
return EXPR_TOKENONLYSIZE;
if (ExprHasProperty(p, EP_Reduced))
return EXPR_REDUCEDSIZE;
return EXPR_FULLSIZE;
}
/*
** The dupedExpr*Size() routines each return the number of bytes required
** to store a copy of an expression or expression tree. They differ in
** how much of the tree is measured.
**
** dupedExprStructSize() Size of only the Expr structure
** dupedExprNodeSize() Size of Expr + space for token
** dupedExprSize() Expr + token + subtree components
**
***************************************************************************
**
** The dupedExprStructSize() function returns two values OR-ed together:
** (1) the space required for a copy of the Expr structure only and
** (2) the EP_xxx flags that indicate what the structure size should be.
** The return values is always one of:
**
** EXPR_FULLSIZE
** EXPR_REDUCEDSIZE | EP_Reduced
** EXPR_TOKENONLYSIZE | EP_TokenOnly
**
** The size of the structure can be found by masking the return value
** of this routine with 0xfff. The flags can be found by masking the
** return value with EP_Reduced|EP_TokenOnly.
**
** Note that with flags==EXPRDUP_REDUCE, this routines works on full-size
** (unreduced) Expr objects as they or originally constructed by the parser.
** During expression analysis, extra information is computed and moved into
** later parts of teh Expr object and that extra information might get chopped
** off if the expression is reduced. Note also that it does not work to
** make a EXPRDUP_REDUCE copy of a reduced expression. It is only legal
** to reduce a pristine expression tree from the parser. The implementation
** of dupedExprStructSize() contain multiple Debug.Assert() statements that attempt
** to enforce this constraint.
*/
private static int dupedExprStructSize(Expr p, int flags)
{
int nSize;
Debug.Assert(flags == EXPRDUP_REDUCE || flags == 0); /* Only one flag value allowed */
if (0 == (flags & EXPRDUP_REDUCE))
{
nSize = EXPR_FULLSIZE;
}
else
{
Debug.Assert(!ExprHasAnyProperty(p, EP_TokenOnly | EP_Reduced));
Debug.Assert(!ExprHasProperty(p, EP_FromJoin));
Debug.Assert((p.flags2 & EP2_MallocedToken) == 0);
Debug.Assert((p.flags2 & EP2_Irreducible) == 0);
if (p.pLeft != null || p.pRight != null || p.pColl != null || p.x.pList != null || p.x.pSelect != null)
{
nSize = EXPR_REDUCEDSIZE | EP_Reduced;
}
else
{
nSize = EXPR_TOKENONLYSIZE | EP_TokenOnly;
}
}
return nSize;
}
/*
** This function returns the space in bytes required to store the copy
** of the Expr structure and a copy of the Expr.u.zToken string (if that
** string is defined.)
*/
private static int dupedExprNodeSize(Expr p, int flags)
{
int nByte = dupedExprStructSize(p, flags) & 0xfff;
if (!ExprHasProperty(p, EP_IntValue) && p.u.zToken != null)
{
nByte += sqlite3Strlen30(p.u.zToken) + 1;
}
return ROUND8(nByte);
}
/*
** Return the number of bytes required to create a duplicate of the
** expression passed as the first argument. The second argument is a
** mask containing EXPRDUP_XXX flags.
**
** The value returned includes space to create a copy of the Expr struct
** itself and the buffer referred to by Expr.u.zToken, if any.
**
** If the EXPRDUP_REDUCE flag is set, then the return value includes
** space to duplicate all Expr nodes in the tree formed by Expr.pLeft
** and Expr.pRight variables (but not for any structures pointed to or
** descended from the Expr.x.pList or Expr.x.pSelect variables).
*/
private static int dupedExprSize(Expr p, int flags)
{
int nByte = 0;
if (p != null)
{
nByte = dupedExprNodeSize(p, flags);
if ((flags & EXPRDUP_REDUCE) != 0)
{
nByte += dupedExprSize(p.pLeft, flags) + dupedExprSize(p.pRight, flags);
}
}
return nByte;
}
/*
** This function is similar to sqlite3ExprDup(), except that if pzBuffer
** is not NULL then *pzBuffer is assumed to point to a buffer large enough
** to store the copy of expression p, the copies of p->u.zToken
** (if applicable), and the copies of the p->pLeft and p->pRight expressions,
** if any. Before returning, *pzBuffer is set to the first byte passed the
** portion of the buffer copied into by this function.
*/
private static Expr exprDup(sqlite3 db, Expr p, int flags, ref Expr pzBuffer)
{
Expr pNew = null; /* Value to return */
if (p != null)
{
bool isReduced = (flags & EXPRDUP_REDUCE) != 0;
////Expr zAlloc = new Expr();
u32 staticFlag = 0;
Debug.Assert(pzBuffer == null || isReduced);
/* Figure out where to write the new Expr structure. */
//if ( pzBuffer !=null)
//{
// zAlloc = pzBuffer;
// staticFlag = EP_Static;
//}
//else
//{
///Expr zAlloc = new Expr();//sqlite3DbMallocRaw( db, dupedExprSize( p, flags ) );
//}
// (Expr)zAlloc;
//if ( pNew != null )
{
/* Set nNewSize to the size allocated for the structure pointed to
** by pNew. This is either EXPR_FULLSIZE, EXPR_REDUCEDSIZE or
** EXPR_TOKENONLYSIZE. nToken is set to the number of bytes consumed
** by the copy of the p->u.zToken string (if any).
*/
int nStructSize = dupedExprStructSize(p, flags);
////int nNewSize = nStructSize & 0xfff;
////int nToken;
////if ( !ExprHasProperty( p, EP_IntValue ) && !string.IsNullOrEmpty( p.u.zToken ) )
////{
//// nToken = sqlite3Strlen30( p.u.zToken );
////}
////else
////{
//// nToken = 0;
////}
if (isReduced)
{
Debug.Assert(!ExprHasProperty(p, EP_Reduced));
pNew = p.Copy(EXPR_TOKENONLYSIZE);////memcpy( zAlloc, p, nNewSize );
}
else
{
////int nSize = exprStructSize( p );
////memcpy( zAlloc, p, nSize );
pNew = p.Copy();
////memset( &zAlloc[nSize], 0, EXPR_FULLSIZE - nSize );
}
/* Set the EP_Reduced, EP_TokenOnly, and EP_Static flags appropriately. */
unchecked
{
pNew.flags &= (ushort)(~(EP_Reduced | EP_TokenOnly | EP_Static));
}
pNew.flags |= (ushort)(nStructSize & (EP_Reduced | EP_TokenOnly));
pNew.flags |= (ushort)staticFlag;
/* Copy the p->u.zToken string, if any. */
////if ( nToken != 0 )
////{
//// string zToken;// = pNew.u.zToken = (char)&zAlloc[nNewSize];
//// zToken = p.u.zToken.Substring( 0, nToken );// memcpy( zToken, p.u.zToken, nToken );
////}
if (0 == ((p.flags | pNew.flags) & EP_TokenOnly))
{
/* Fill in the pNew.x.pSelect or pNew.x.pList member. */
if (ExprHasProperty(p, EP_xIsSelect))
{
pNew.x.pSelect = sqlite3SelectDup(db, p.x.pSelect, isReduced ? 1 : 0);
}
else
{
pNew.x.pList = sqlite3ExprListDup(db, p.x.pList, isReduced ? 1 : 0);
}
}
/* Fill in pNew.pLeft and pNew.pRight. */
if (ExprHasAnyProperty(pNew, EP_Reduced | EP_TokenOnly))
{
//zAlloc += dupedExprNodeSize( p, flags );
if (ExprHasProperty(pNew, EP_Reduced))
{
pNew.pLeft = exprDup(db, p.pLeft, EXPRDUP_REDUCE, ref pzBuffer);
pNew.pRight = exprDup(db, p.pRight, EXPRDUP_REDUCE, ref pzBuffer);
}
//if ( pzBuffer != null )
//{
// pzBuffer = zAlloc;
//}
}
else
{
pNew.flags2 = 0;
if (!ExprHasAnyProperty(p, EP_TokenOnly))
{
pNew.pLeft = sqlite3ExprDup(db, p.pLeft, 0);
pNew.pRight = sqlite3ExprDup(db, p.pRight, 0);
}
}
}
}
return pNew;
}
/*
** The following group of routines make deep copies of expressions,
** expression lists, ID lists, and select statements. The copies can
** be deleted (by being passed to their respective ...Delete() routines)
** without effecting the originals.
**
** The expression list, ID, and source lists return by sqlite3ExprListDup(),
** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded
** by subsequent calls to sqlite*ListAppend() routines.
**
** Any tables that the SrcList might point to are not duplicated.
**
** The flags parameter contains a combination of the EXPRDUP_XXX flags.
** If the EXPRDUP_REDUCE flag is set, then the structure returned is a
** truncated version of the usual Expr structure that will be stored as
** part of the in-memory representation of the database schema.
*/
private static Expr sqlite3ExprDup(sqlite3 db, Expr p, int flags)
{
Expr ExprDummy = null;
return exprDup(db, p, flags, ref ExprDummy);
}
private static ExprList sqlite3ExprListDup(sqlite3 db, ExprList p, int flags)
{
ExprList pNew;
ExprList_item pItem;
ExprList_item pOldItem;
if (p == null)
return null;
pNew = new ExprList();//sqlite3DbMallocRaw(db, sizeof(*pNew) );
//if ( pNew == null ) return null;
pNew.iECursor = 0;
pNew.nExpr = pNew.nAlloc = p.nExpr;
pNew.a = new ExprList_item[p.nExpr];//sqlite3DbMallocRaw(db, p.nExpr*sizeof(p.a[0]) );
//if( pItem==null ){
// sqlite3DbFree(db,ref pNew);
// return null;
//}
//pOldItem = p.a;
for (int i = 0; i < p.nExpr; i++)
{//pItem++, pOldItem++){
pItem = pNew.a[i] = new ExprList_item();
pOldItem = p.a[i];
Expr pOldExpr = pOldItem.pExpr;
pItem.pExpr = sqlite3ExprDup(db, pOldExpr, flags);
pItem.zName = pOldItem.zName;// sqlite3DbStrDup(db, pOldItem.zName);
pItem.zSpan = pOldItem.zSpan;// sqlite3DbStrDup( db, pOldItem.zSpan );
pItem.sortOrder = pOldItem.sortOrder;
pItem.done = 0;
pItem.iCol = pOldItem.iCol;
pItem.iAlias = pOldItem.iAlias;
}
return pNew;
}
/*
** If cursors, triggers, views and subqueries are all omitted from
** the build, then none of the following routines, except for
** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes
** called with a NULL argument.
*/
#if !SQLITE_OMIT_VIEW || !SQLITE_OMIT_TRIGGER || !SQLITE_OMIT_SUBQUERY
private static SrcList sqlite3SrcListDup(sqlite3 db, SrcList p, int flags)
{
SrcList pNew;
int nByte;
if (p == null)
return null;
//nByte = sizeof(*p) + (p.nSrc>0 ? sizeof(p.a[0]) * (p.nSrc-1) : 0);
pNew = new SrcList();//sqlite3DbMallocRaw(db, nByte );
if (p.nSrc > 0)
pNew.a = new SrcList_item[p.nSrc];
if (pNew == null)
return null;
pNew.nSrc = pNew.nAlloc = p.nSrc;
for (int i = 0; i < p.nSrc; i++)
{
pNew.a[i] = new SrcList_item();
SrcList_item pNewItem = pNew.a[i];
SrcList_item pOldItem = p.a[i];
Table pTab;
pNewItem.zDatabase = pOldItem.zDatabase;// sqlite3DbStrDup(db, pOldItem.zDatabase);
pNewItem.zName = pOldItem.zName;// sqlite3DbStrDup(db, pOldItem.zName);
pNewItem.zAlias = pOldItem.zAlias;// sqlite3DbStrDup(db, pOldItem.zAlias);
pNewItem.jointype = pOldItem.jointype;
pNewItem.iCursor = pOldItem.iCursor;
pNewItem.isPopulated = pOldItem.isPopulated;
pNewItem.zIndex = pOldItem.zIndex;// sqlite3DbStrDup( db, pOldItem.zIndex );
pNewItem.notIndexed = pOldItem.notIndexed;
pNewItem.pIndex = pOldItem.pIndex;
pTab = pNewItem.pTab = pOldItem.pTab;
if (pTab != null)
{
pTab.nRef++;
}
pNewItem.pSelect = sqlite3SelectDup(db, pOldItem.pSelect, flags);
pNewItem.pOn = sqlite3ExprDup(db, pOldItem.pOn, flags);
pNewItem.pUsing = sqlite3IdListDup(db, pOldItem.pUsing);
pNewItem.colUsed = pOldItem.colUsed;
}
return pNew;
}
private static IdList sqlite3IdListDup(sqlite3 db, IdList p)
{
IdList pNew;
int i;
if (p == null)
return null;
pNew = new IdList();//sqlite3DbMallocRaw(db, sizeof(*pNew) );
if (pNew == null)
return null;
pNew.nId = pNew.nAlloc = p.nId;
pNew.a = new IdList_item[p.nId];//sqlite3DbMallocRaw(db, p.nId*sizeof(p.a[0]) );
if (pNew.a == null)
{
sqlite3DbFree(db, ref pNew);
return null;
}
for (i = 0; i < p.nId; i++)
{
pNew.a[i] = new IdList_item();
IdList_item pNewItem = pNew.a[i];
IdList_item pOldItem = p.a[i];
pNewItem.zName = pOldItem.zName;// sqlite3DbStrDup(db, pOldItem.zName);
pNewItem.idx = pOldItem.idx;
}
return pNew;
}
private static Select sqlite3SelectDup(sqlite3 db, Select p, int flags)
{
Select pNew;
if (p == null)
return null;
pNew = new Select();//sqlite3DbMallocRaw(db, sizeof(*p) );
//if ( pNew == null ) return null;
pNew.pEList = sqlite3ExprListDup(db, p.pEList, flags);
pNew.pSrc = sqlite3SrcListDup(db, p.pSrc, flags);
pNew.pWhere = sqlite3ExprDup(db, p.pWhere, flags);
pNew.pGroupBy = sqlite3ExprListDup(db, p.pGroupBy, flags);
pNew.pHaving = sqlite3ExprDup(db, p.pHaving, flags);
pNew.pOrderBy = sqlite3ExprListDup(db, p.pOrderBy, flags);
pNew.op = p.op;
pNew.pPrior = sqlite3SelectDup(db, p.pPrior, flags);
pNew.pLimit = sqlite3ExprDup(db, p.pLimit, flags);
pNew.pOffset = sqlite3ExprDup(db, p.pOffset, flags);
pNew.iLimit = 0;
pNew.iOffset = 0;
pNew.selFlags = (u16)(p.selFlags & ~SF_UsesEphemeral);
pNew.pRightmost = null;
pNew.addrOpenEphm[0] = -1;
pNew.addrOpenEphm[1] = -1;
pNew.addrOpenEphm[2] = -1;
return pNew;
}
#else
Select sqlite3SelectDup(sqlite3 db, Select p, int flags){
Debug.Assert( p==null );
return null;
}
#endif
/*
** Add a new element to the end of an expression list. If pList is
** initially NULL, then create a new expression list.
**
** If a memory allocation error occurs, the entire list is freed and
** NULL is returned. If non-NULL is returned, then it is guaranteed
** that the new entry was successfully appended.
*/
// OVERLOADS, so I don't need to rewrite parse.c
private static ExprList sqlite3ExprListAppend(Parse pParse, int null_2, Expr pExpr)
{
return sqlite3ExprListAppend(pParse, null, pExpr);
}
private static ExprList sqlite3ExprListAppend(
Parse pParse, /* Parsing context */
ExprList pList, /* List to which to append. Might be NULL */
Expr pExpr /* Expression to be appended. Might be NULL */
)
{
////sqlite3 db = pParse.db;
if (pList == null)
{
pList = new ExprList(); //sqlite3DbMallocZero(db, ExprList).Length;
//if ( pList == null )
//{
// goto no_mem;
//}
Debug.Assert(pList.nAlloc == 0);
}
if (pList.nAlloc <= pList.nExpr)
{
ExprList_item a;
int n = pList.nAlloc * 2 + 4;
//a = sqlite3DbRealloc(db, pList.a, n*sizeof(pList.a[0]));
//if( a==0 ){
// goto no_mem;
//}
Array.Resize(ref pList.a, n);// = a;
pList.nAlloc = pList.a.Length;// sqlite3DbMallocSize(db, a)/sizeof(a[0]);
}
Debug.Assert(pList.a != null);
if (true)
{
pList.a[pList.nExpr] = new ExprList_item();
//ExprList_item pItem = pList.a[pList.nExpr++];
//pItem = new ExprList_item();//memset(pItem, 0, sizeof(*pItem));
//pItem.pExpr = pExpr;
pList.a[pList.nExpr++].pExpr = pExpr;
}
return pList;
//no_mem:
// /* Avoid leaking memory if malloc has failed. */
// sqlite3ExprDelete( db, ref pExpr );
// sqlite3ExprListDelete( db, ref pList );
// return null;
}
/*
** Set the ExprList.a[].zName element of the most recently added item
** on the expression list.
**
** pList might be NULL following an OOM error. But pName should never be
** NULL. If a memory allocation fails, the pParse.db.mallocFailed flag
** is set.
*/
private static void sqlite3ExprListSetName(
Parse pParse, /* Parsing context */
ExprList pList, /* List to which to add the span. */
Token pName, /* Name to be added */
int dequote /* True to cause the name to be dequoted */
)
{
Debug.Assert(pList != null /* || pParse.db.mallocFailed != 0 */ );
if (pList != null)
{
ExprList_item pItem;
Debug.Assert(pList.nExpr > 0);
pItem = pList.a[pList.nExpr - 1];
Debug.Assert(pItem.zName == null);
pItem.zName = pName.z.Substring(0, pName.n);//sqlite3DbStrNDup(pParse.db, pName.z, pName.n);
if (dequote != 0 && !string.IsNullOrEmpty(pItem.zName))
sqlite3Dequote(ref pItem.zName);
}
}
/*
** Set the ExprList.a[].zSpan element of the most recently added item
** on the expression list.
**
** pList might be NULL following an OOM error. But pSpan should never be
** NULL. If a memory allocation fails, the pParse.db.mallocFailed flag
** is set.
*/
private static void sqlite3ExprListSetSpan(
Parse pParse, /* Parsing context */
ExprList pList, /* List to which to add the span. */
ExprSpan pSpan /* The span to be added */
)
{
sqlite3 db = pParse.db;
Debug.Assert(pList != null /*|| db.mallocFailed != 0 */ );
if (pList != null)
{
ExprList_item pItem = pList.a[pList.nExpr - 1];
Debug.Assert(pList.nExpr > 0);
Debug.Assert( /* db.mallocFailed != 0 || */ pItem.pExpr == pSpan.pExpr);
sqlite3DbFree(db, ref pItem.zSpan);
pItem.zSpan = pSpan.zStart.Substring(0, pSpan.zStart.Length <= pSpan.zEnd.Length ? pSpan.zStart.Length : pSpan.zStart.Length - pSpan.zEnd.Length);// sqlite3DbStrNDup( db, pSpan.zStart,
//(int)( pSpan.zEnd- pSpan.zStart) );
}
}
/*
** If the expression list pEList contains more than iLimit elements,
** leave an error message in pParse.
*/
private static void sqlite3ExprListCheckLength(
Parse pParse,
ExprList pEList,
string zObject
)
{
int mx = pParse.db.aLimit[SQLITE_LIMIT_COLUMN];
testcase(pEList != null && pEList.nExpr == mx);
testcase(pEList != null && pEList.nExpr == mx + 1);
if (pEList != null && pEList.nExpr > mx)
{
sqlite3ErrorMsg(pParse, "too many columns in %s", zObject);
}
}
/*
** Delete an entire expression list.
*/
private static void sqlite3ExprListDelete(sqlite3 db, ref ExprList pList)
{
int i;
ExprList_item pItem;
if (pList == null)
return;
Debug.Assert(pList.a != null || (pList.nExpr == 0 && pList.nAlloc == 0));
Debug.Assert(pList.nExpr <= pList.nAlloc);
for (i = 0; i < pList.nExpr; i++)
{
if ((pItem = pList.a[i]) != null)
{
sqlite3ExprDelete(db, ref pItem.pExpr);
sqlite3DbFree(db, ref pItem.zName);
sqlite3DbFree(db, ref pItem.zSpan);
}
}
sqlite3DbFree(db, ref pList.a);
sqlite3DbFree(db, ref pList);
}
/*
** These routines are Walker callbacks. Walker.u.pi is a pointer
** to an integer. These routines are checking an expression to see
** if it is a constant. Set *Walker.u.pi to 0 if the expression is
** not constant.
**
** These callback routines are used to implement the following:
**
** sqlite3ExprIsConstant()
** sqlite3ExprIsConstantNotJoin()
** sqlite3ExprIsConstantOrFunction()
**
*/
private static int exprNodeIsConstant(Walker pWalker, ref Expr pExpr)
{
/* If pWalker.u.i is 3 then any term of the expression that comes from
** the ON or USING clauses of a join disqualifies the expression
** from being considered constant. */
if (pWalker.u.i == 3 && ExprHasAnyProperty(pExpr, EP_FromJoin))
{
pWalker.u.i = 0;
return WRC_Abort;
}
switch (pExpr.op)
{
/* Consider functions to be constant if all their arguments are constant
** and pWalker.u.i==2 */
case TK_FUNCTION:
if ((pWalker.u.i) == 2)
return 0;
goto case TK_ID;
/* Fall through */
case TK_ID:
case TK_COLUMN:
case TK_AGG_FUNCTION:
case TK_AGG_COLUMN:
testcase(pExpr.op == TK_ID);
testcase(pExpr.op == TK_COLUMN);
testcase(pExpr.op == TK_AGG_FUNCTION);
testcase(pExpr.op == TK_AGG_COLUMN);
pWalker.u.i = 0;
return WRC_Abort;
default:
testcase(pExpr.op == TK_SELECT); /* selectNodeIsConstant will disallow */
testcase(pExpr.op == TK_EXISTS); /* selectNodeIsConstant will disallow */
return WRC_Continue;
}
}
private static int selectNodeIsConstant(Walker pWalker, Select NotUsed)
{
UNUSED_PARAMETER(NotUsed);
pWalker.u.i = 0;
return WRC_Abort;
}
private static int exprIsConst(Expr p, int initFlag)
{
Walker w = new Walker();
w.u.i = initFlag;
w.xExprCallback = exprNodeIsConstant;
w.xSelectCallback = selectNodeIsConstant;
sqlite3WalkExpr(w, ref p);
return w.u.i;
}
/*
** Walk an expression tree. Return 1 if the expression is constant
** and 0 if it involves variables or function calls.
**
** For the purposes of this function, a double-quoted string (ex: "abc")
** is considered a variable but a single-quoted string (ex: 'abc') is
** a constant.
*/
private static int sqlite3ExprIsConstant(Expr p)
{
return exprIsConst(p, 1);
}
/*
** Walk an expression tree. Return 1 if the expression is constant
** that does no originate from the ON or USING clauses of a join.
** Return 0 if it involves variables or function calls or terms from
** an ON or USING clause.
*/
private static int sqlite3ExprIsConstantNotJoin(Expr p)
{
return exprIsConst(p, 3);
}
/*
** Walk an expression tree. Return 1 if the expression is constant
** or a function call with constant arguments. Return and 0 if there
** are any variables.
**
** For the purposes of this function, a double-quoted string (ex: "abc")
** is considered a variable but a single-quoted string (ex: 'abc') is
** a constant.
*/
private static int sqlite3ExprIsConstantOrFunction(Expr p)
{
return exprIsConst(p, 2);
}
/*
** If the expression p codes a constant integer that is small enough
** to fit in a 32-bit integer, return 1 and put the value of the integer
** in pValue. If the expression is not an integer or if it is too big
** to fit in a signed 32-bit integer, return 0 and leave pValue unchanged.
*/
private static int sqlite3ExprIsInteger(Expr p, ref int pValue)
{
int rc = 0;
/* If an expression is an integer literal that fits in a signed 32-bit
** integer, then the EP_IntValue flag will have already been set */
Debug.Assert(p.op != TK_INTEGER || (p.flags & EP_IntValue) != 0
|| !sqlite3GetInt32(p.u.zToken, ref rc));
if ((p.flags & EP_IntValue) != 0)
{
pValue = (int)p.u.iValue;
return 1;
}
switch (p.op)
{
case TK_UPLUS:
{
rc = sqlite3ExprIsInteger(p.pLeft, ref pValue);
break;
}
case TK_UMINUS:
{
int v = 0;
if (sqlite3ExprIsInteger(p.pLeft, ref v) != 0)
{
pValue = -v;
rc = 1;
}
break;
}
default:
break;
}
return rc;
}
/*
** Return FALSE if there is no chance that the expression can be NULL.
**
** If the expression might be NULL or if the expression is too complex
** to tell return TRUE.
**
** This routine is used as an optimization, to skip OP_IsNull opcodes
** when we know that a value cannot be NULL. Hence, a false positive
** (returning TRUE when in fact the expression can never be NULL) might
** be a small performance hit but is otherwise harmless. On the other
** hand, a false negative (returning FALSE when the result could be NULL)
** will likely result in an incorrect answer. So when in doubt, return
** TRUE.
*/
private static int sqlite3ExprCanBeNull(Expr p)
{
u8 op;
while (p.op == TK_UPLUS || p.op == TK_UMINUS)
{
p = p.pLeft;
}
op = p.op;
if (op == TK_REGISTER)
op = p.op2;
switch (op)
{
case TK_INTEGER:
case TK_STRING:
case TK_FLOAT:
case TK_BLOB:
return 0;
default:
return 1;
}
}
/*
** Generate an OP_IsNull instruction that tests register iReg and jumps
** to location iDest if the value in iReg is NULL. The value in iReg
** was computed by pExpr. If we can look at pExpr at compile-time and
** determine that it can never generate a NULL, then the OP_IsNull operation
** can be omitted.
*/
private static void sqlite3ExprCodeIsNullJump(
Vdbe v, /* The VDBE under construction */
Expr pExpr, /* Only generate OP_IsNull if this expr can be NULL */
int iReg, /* Test the value in this register for NULL */
int iDest /* Jump here if the value is null */
)
{
if (sqlite3ExprCanBeNull(pExpr) != 0)
{
sqlite3VdbeAddOp2(v, OP_IsNull, iReg, iDest);
}
}
/*
** Return TRUE if the given expression is a constant which would be
** unchanged by OP_Affinity with the affinity given in the second
** argument.
**
** This routine is used to determine if the OP_Affinity operation
** can be omitted. When in doubt return FALSE. A false negative
** is harmless. A false positive, however, can result in the wrong
** answer.
*/
private static int sqlite3ExprNeedsNoAffinityChange(Expr p, char aff)
{
u8 op;
if (aff == SQLITE_AFF_NONE)
return 1;
while (p.op == TK_UPLUS || p.op == TK_UMINUS)
{
p = p.pLeft;
}
op = p.op;
if (op == TK_REGISTER)
op = p.op2;
switch (op)
{
case TK_INTEGER:
{
return (aff == SQLITE_AFF_INTEGER || aff == SQLITE_AFF_NUMERIC) ? 1 : 0;
}
case TK_FLOAT:
{
return (aff == SQLITE_AFF_REAL || aff == SQLITE_AFF_NUMERIC) ? 1 : 0;
}
case TK_STRING:
{
return (aff == SQLITE_AFF_TEXT) ? 1 : 0;
}
case TK_BLOB:
{
return 1;
}
case TK_COLUMN:
{
Debug.Assert(p.iTable >= 0); /* p cannot be part of a CHECK constraint */
return (p.iColumn < 0
&& (aff == SQLITE_AFF_INTEGER || aff == SQLITE_AFF_NUMERIC)) ? 1 : 0;
}
default:
{
return 0;
}
}
}
/*
** Return TRUE if the given string is a row-id column name.
*/
private static bool sqlite3IsRowid(string z)
{
if (z.Equals("_ROWID_", StringComparison.OrdinalIgnoreCase))
return true;
if (z.Equals("ROWID", StringComparison.OrdinalIgnoreCase))
return true;
if (z.Equals("OID", StringComparison.OrdinalIgnoreCase))
return true;
return false;
}
/*
** Return true if we are able to the IN operator optimization on a
** query of the form
**
** x IN (SELECT ...)
**
** Where the SELECT... clause is as specified by the parameter to this
** routine.
**
** The Select object passed in has already been preprocessed and no
** errors have been found.
*/
#if !SQLITE_OMIT_SUBQUERY
private static int isCandidateForInOpt(Select p)
{
SrcList pSrc;
ExprList pEList;
Table pTab;
if (p == null)
return 0; /* right-hand side of IN is SELECT */
if (p.pPrior != null)
return 0; /* Not a compound SELECT */
if ((p.selFlags & (SF_Distinct | SF_Aggregate)) != 0)
{
testcase((p.selFlags & (SF_Distinct | SF_Aggregate)) == SF_Distinct);
testcase((p.selFlags & (SF_Distinct | SF_Aggregate)) == SF_Aggregate);
return 0; /* No DISTINCT keyword and no aggregate functions */
}
Debug.Assert(p.pGroupBy == null); /* Has no GROUP BY clause */
if (p.pLimit != null)
return 0; /* Has no LIMIT clause */
Debug.Assert(p.pOffset == null); /* No LIMIT means no OFFSET */
if (p.pWhere != null)
return 0; /* Has no WHERE clause */
pSrc = p.pSrc;
Debug.Assert(pSrc != null);
if (pSrc.nSrc != 1)
return 0; /* Single term in FROM clause */
if (pSrc.a[0].pSelect != null)
return 0; /* FROM is not a subquery or view */
pTab = pSrc.a[0].pTab;
if (NEVER(pTab == null))
return 0;
Debug.Assert(pTab.pSelect == null); /* FROM clause is not a view */
if (IsVirtual(pTab))
return 0; /* FROM clause not a virtual table */
pEList = p.pEList;
if (pEList.nExpr != 1)
return 0; /* One column in the result set */
if (pEList.a[0].pExpr.op != TK_COLUMN)
return 0; /* Result is a column */
return 1;
}
#endif //* SQLITE_OMIT_SUBQUERY */
/*
** This function is used by the implementation of the IN (...) operator.
** It's job is to find or create a b-tree structure that may be used
** either to test for membership of the (...) set or to iterate through
** its members, skipping duplicates.
**
** The index of the cursor opened on the b-tree (database table, database index
** or ephermal table) is stored in pX->iTable before this function returns.
** The returned value of this function indicates the b-tree type, as follows:
**
** IN_INDEX_ROWID - The cursor was opened on a database table.
** IN_INDEX_INDEX - The cursor was opened on a database index.
** IN_INDEX_EPH - The cursor was opened on a specially created and
** populated epheremal table.
**
** An existing b-tree may only be used if the SELECT is of the simple
** form:
**
** SELECT <column> FROM <table>
**
** If the prNotFound parameter is 0, then the b-tree will be used to iterate
** through the set members, skipping any duplicates. In this case an
** epheremal table must be used unless the selected <column> is guaranteed
** to be unique - either because it is an INTEGER PRIMARY KEY or it
** has a UNIQUE constraint or UNIQUE index.
**
** If the prNotFound parameter is not 0, then the b-tree will be used
** for fast set membership tests. In this case an epheremal table must
** be used unless <column> is an INTEGER PRIMARY KEY or an index can
** be found with <column> as its left-most column.
**
** When the b-tree is being used for membership tests, the calling function
** needs to know whether or not the structure contains an SQL NULL
** value in order to correctly evaluate expressions like "X IN (Y, Z)".
** If there is any chance that the (...) might contain a NULL value at
** runtime, then a register is allocated and the register number written
** to *prNotFound. If there is no chance that the (...) contains a
** NULL value, then *prNotFound is left unchanged.
**
** If a register is allocated and its location stored in *prNotFound, then
** its initial value is NULL. If the (...) does not remain constant
** for the duration of the query (i.e. the SELECT within the (...)
** is a correlated subquery) then the value of the allocated register is
** reset to NULL each time the subquery is rerun. This allows the
** caller to use vdbe code equivalent to the following:
**
** if( register==NULL ){
** has_null = <test if data structure contains null>
** register = 1
** }
**
** in order to avoid running the <test if data structure contains null>
** test more often than is necessary.
*/
#if !SQLITE_OMIT_SUBQUERY
private static int sqlite3FindInIndex(Parse pParse, Expr pX, ref int prNotFound)
{
Select p; /* SELECT to the right of IN operator */
int eType = 0; /* Type of RHS table. IN_INDEX_* */
int iTab = pParse.nTab++; /* Cursor of the RHS table */
bool mustBeUnique = (prNotFound != 0); /* True if RHS must be unique */
Debug.Assert(pX.op == TK_IN);
/* Check to see if an existing table or index can be used to
** satisfy the query. This is preferable to generating a new
** ephemeral table.
*/
p = (ExprHasProperty(pX, EP_xIsSelect) ? pX.x.pSelect : null);
if (ALWAYS(pParse.nErr == 0) && isCandidateForInOpt(p) != 0)
{
sqlite3 db = pParse.db; /* Database connection */
Expr pExpr = p.pEList.a[0].pExpr; /* Expression <column> */
int iCol = pExpr.iColumn; /* Index of column <column> */
Vdbe v = sqlite3GetVdbe(pParse); /* Virtual machine being coded */
Table pTab = p.pSrc.a[0].pTab; /* Table <table>. */
int iDb; /* Database idx for pTab */
/* Code an OP_VerifyCookie and OP_TableLock for <table>. */
iDb = sqlite3SchemaToIndex(db, pTab.pSchema);
sqlite3CodeVerifySchema(pParse, iDb);
sqlite3TableLock(pParse, iDb, pTab.tnum, 0, pTab.zName);
/* This function is only called from two places. In both cases the vdbe
** has already been allocated. So assume sqlite3GetVdbe() is always
** successful here.
*/
Debug.Assert(v != null);
if (iCol < 0)
{
int iMem = ++pParse.nMem;
int iAddr;
iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
eType = IN_INDEX_ROWID;
sqlite3VdbeJumpHere(v, iAddr);
}
else
{
Index pIdx; /* Iterator variable */
/* The collation sequence used by the comparison. If an index is to
** be used in place of a temp.table, it must be ordered according
** to this collation sequence. */
CollSeq pReq = sqlite3BinaryCompareCollSeq(pParse, pX.pLeft, pExpr);
/* Check that the affinity that will be used to perform the
** comparison is the same as the affinity of the column. If
** it is not, it is not possible to use any index.
*/
char aff = comparisonAffinity(pX);
bool affinity_ok = (pTab.aCol[iCol].affinity == aff || aff == SQLITE_AFF_NONE);
for (pIdx = pTab.pIndex; pIdx != null && eType == 0 && affinity_ok; pIdx = pIdx.pNext)
{
if ((pIdx.aiColumn[0] == iCol)
&& (sqlite3FindCollSeq(db, ENC(db), pIdx.azColl[0], 0) == pReq)
&& (mustBeUnique == false || (pIdx.nColumn == 1 && pIdx.onError != OE_None))
)
{
int iMem = ++pParse.nMem;
int iAddr;
KeyInfo pKey;
pKey = sqlite3IndexKeyinfo(pParse, pIdx);
iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
sqlite3VdbeAddOp4(v, OP_OpenRead, iTab, pIdx.tnum, iDb,
pKey, P4_KEYINFO_HANDOFF);
#if SQLITE_DEBUG
VdbeComment(v, "%s", pIdx.zName);
#endif
eType = IN_INDEX_INDEX;
sqlite3VdbeJumpHere(v, iAddr);
if ( //prNotFound != null && -- always exists under C#
pTab.aCol[iCol].notNull == 0)
{
prNotFound = ++pParse.nMem;
}
}
}
}
}
if (eType == 0)
{
/* Could not found an existing table or index to use as the RHS b-tree.
** We will have to generate an ephemeral table to do the job.
*/
double savedNQueryLoop = pParse.nQueryLoop;
int rMayHaveNull = 0;
eType = IN_INDEX_EPH;
if (prNotFound != -1) // Klude to show prNotFound not available
{
prNotFound = rMayHaveNull = ++pParse.nMem;
}
else
{
testcase(pParse.nQueryLoop > (double)1);
pParse.nQueryLoop = (double)1;
if (pX.pLeft.iColumn < 0 && !ExprHasAnyProperty(pX, EP_xIsSelect))
{
eType = IN_INDEX_ROWID;
}
}
sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType == IN_INDEX_ROWID);
pParse.nQueryLoop = savedNQueryLoop;
}
else
{
pX.iTable = iTab;
}
return eType;
}
#endif
/*
** Generate code for scalar subqueries used as a subquery expression, EXISTS,
** or IN operators. Examples:
**
** (SELECT a FROM b) -- subquery
** EXISTS (SELECT a FROM b) -- EXISTS subquery
** x IN (4,5,11) -- IN operator with list on right-hand side
** x IN (SELECT a FROM b) -- IN operator with subquery on the right
**
** The pExpr parameter describes the expression that contains the IN
** operator or subquery.
**
** If parameter isRowid is non-zero, then expression pExpr is guaranteed
** to be of the form "<rowid> IN (?, ?, ?)", where <rowid> is a reference
** to some integer key column of a table B-Tree. In this case, use an
** intkey B-Tree to store the set of IN(...) values instead of the usual
** (slower) variable length keys B-Tree.
**
** If rMayHaveNull is non-zero, that means that the operation is an IN
** (not a SELECT or EXISTS) and that the RHS might contains NULLs.
** Furthermore, the IN is in a WHERE clause and that we really want
** to iterate over the RHS of the IN operator in order to quickly locate
** all corresponding LHS elements. All this routine does is initialize
** the register given by rMayHaveNull to NULL. Calling routines will take
** care of changing this register value to non-NULL if the RHS is NULL-free.
**
** If rMayHaveNull is zero, that means that the subquery is being used
** for membership testing only. There is no need to initialize any
** registers to indicate the presense or absence of NULLs on the RHS.
**
** For a SELECT or EXISTS operator, return the register that holds the
** result. For IN operators or if an error occurs, the return value is 0.
*/
#if !SQLITE_OMIT_SUBQUERY
private static int sqlite3CodeSubselect(
Parse pParse, /* Parsing context */
Expr pExpr, /* The IN, SELECT, or EXISTS operator */
int rMayHaveNull, /* Register that records whether NULLs exist in RHS */
bool isRowid /* If true, LHS of IN operator is a rowid */
)
{
int testAddr = 0; /* One-time test address */
int rReg = 0; /* Register storing resulting */
Vdbe v = sqlite3GetVdbe(pParse);
if (NEVER(v == null))
return 0;
sqlite3ExprCachePush(pParse);
/* This code must be run in its entirety every time it is encountered
** if any of the following is true:
**
** * The right-hand side is a correlated subquery
** * The right-hand side is an expression list containing variables
** * We are inside a trigger
**
** If all of the above are false, then we can run this code just once
** save the results, and reuse the same result on subsequent invocations.
*/
if (!ExprHasAnyProperty(pExpr, EP_VarSelect) && null == pParse.pTriggerTab)
{
int mem = ++pParse.nMem;
sqlite3VdbeAddOp1(v, OP_If, mem);
testAddr = sqlite3VdbeAddOp2(v, OP_Integer, 1, mem);
Debug.Assert(testAddr > 0 /* || pParse.db.mallocFailed != 0 */ );
}
#if !SQLITE_OMIT_EXPLAIN
if (pParse.explain == 2)
{
string zMsg = sqlite3MPrintf(
pParse.db, "EXECUTE %s%s SUBQUERY %d", testAddr != 0 ? string.Empty : "CORRELATED ",
pExpr.op == TK_IN ? "LIST" : "SCALAR", pParse.iNextSelectId
);
sqlite3VdbeAddOp4(v, OP_Explain, pParse.iSelectId, 0, 0, zMsg, P4_DYNAMIC);
}
#endif
switch (pExpr.op)
{
case TK_IN:
{
char affinity; /* Affinity of the LHS of the IN */
KeyInfo keyInfo; /* Keyinfo for the generated table */
int addr; /* Address of OP_OpenEphemeral instruction */
Expr pLeft = pExpr.pLeft; /* the LHS of the IN operator */
if (rMayHaveNull != 0)
{
sqlite3VdbeAddOp2(v, OP_Null, 0, rMayHaveNull);
}
affinity = sqlite3ExprAffinity(pLeft);
/* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
** expression it is handled the same way. An ephemeral table is
** filled with single-field index keys representing the results
** from the SELECT or the <exprlist>.
**
** If the 'x' expression is a column value, or the SELECT...
** statement returns a column value, then the affinity of that
** column is used to build the index keys. If both 'x' and the
** SELECT... statement are columns, then numeric affinity is used
** if either column has NUMERIC or INTEGER affinity. If neither
** 'x' nor the SELECT... statement are columns, then numeric affinity
** is used.
*/
pExpr.iTable = pParse.nTab++;
addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, (int)pExpr.iTable, !isRowid);
if (rMayHaveNull == 0)
sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
keyInfo = new KeyInfo();// memset( &keyInfo, 0, sizeof(keyInfo ));
keyInfo.nField = 1;
if (ExprHasProperty(pExpr, EP_xIsSelect))
{
/* Case 1: expr IN (SELECT ...)
**
** Generate code to write the results of the select into the temporary
** table allocated and opened above.
*/
SelectDest dest = new SelectDest();
ExprList pEList;
Debug.Assert(!isRowid);
sqlite3SelectDestInit(dest, SRT_Set, pExpr.iTable);
dest.affinity = (char)affinity;
Debug.Assert((pExpr.iTable & 0x0000FFFF) == pExpr.iTable);
pExpr.x.pSelect.iLimit = 0;
if (sqlite3Select(pParse, pExpr.x.pSelect, ref dest) != 0)
{
return 0;
}
pEList = pExpr.x.pSelect.pEList;
if (ALWAYS(pEList != null) && pEList.nExpr > 0)
{
keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr.pLeft,
pEList.a[0].pExpr);
}
}
else if (ALWAYS(pExpr.x.pList != null))
{
/* Case 2: expr IN (exprlist)
**
** For each expression, build an index key from the evaluation and
** store it in the temporary table. If <expr> is a column, then use
** that columns affinity when building index keys. If <expr> is not
** a column, use numeric affinity.
*/
int i;
ExprList pList = pExpr.x.pList;
ExprList_item pItem;
int r1, r2, r3;
if (affinity == '\0')
{
affinity = SQLITE_AFF_NONE;
}
keyInfo.aColl[0] = sqlite3ExprCollSeq(pParse, pExpr.pLeft);
/* Loop through each expression in <exprlist>. */
r1 = sqlite3GetTempReg(pParse);
r2 = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_Null, 0, r2);
for (i = 0; i < pList.nExpr; i++)
{//, pItem++){
pItem = pList.a[i];
Expr pE2 = pItem.pExpr;
int iValToIns = 0;
/* If the expression is not constant then we will need to
** disable the test that was generated above that makes sure
** this code only executes once. Because for a non-constant
** expression we need to rerun this code each time.
*/
if (testAddr != 0 && sqlite3ExprIsConstant(pE2) == 0)
{
sqlite3VdbeChangeToNoop(v, testAddr - 1, 2);
testAddr = 0;
}
/* Evaluate the expression and insert it into the temp table */
if (isRowid && sqlite3ExprIsInteger(pE2, ref iValToIns) != 0)
{
sqlite3VdbeAddOp3(v, OP_InsertInt, pExpr.iTable, r2, iValToIns);
}
else
{
r3 = sqlite3ExprCodeTarget(pParse, pE2, r1);
if (isRowid)
{
sqlite3VdbeAddOp2(v, OP_MustBeInt, r3,
sqlite3VdbeCurrentAddr(v) + 2);
sqlite3VdbeAddOp3(v, OP_Insert, pExpr.iTable, r2, r3);
}
else
{
sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, affinity, 1);
sqlite3ExprCacheAffinityChange(pParse, r3, 1);
sqlite3VdbeAddOp2(v, OP_IdxInsert, pExpr.iTable, r2);
}
}
}
sqlite3ReleaseTempReg(pParse, r1);
sqlite3ReleaseTempReg(pParse, r2);
}
if (!isRowid)
{
sqlite3VdbeChangeP4(v, addr, keyInfo, P4_KEYINFO);
}
break;
}
case TK_EXISTS:
case TK_SELECT:
default:
{
/* If this has to be a scalar SELECT. Generate code to put the
** value of this select in a memory cell and record the number
** of the memory cell in iColumn. If this is an EXISTS, write
** an integer 0 (not exists) or 1 (exists) into a memory cell
** and record that memory cell in iColumn.
*/
Select pSel; /* SELECT statement to encode */
SelectDest dest = new SelectDest(); /* How to deal with SELECt result */
testcase(pExpr.op == TK_EXISTS);
testcase(pExpr.op == TK_SELECT);
Debug.Assert(pExpr.op == TK_EXISTS || pExpr.op == TK_SELECT);
Debug.Assert(ExprHasProperty(pExpr, EP_xIsSelect));
pSel = pExpr.x.pSelect;
sqlite3SelectDestInit(dest, 0, ++pParse.nMem);
if (pExpr.op == TK_SELECT)
{
dest.eDest = SRT_Mem;
sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iParm);
#if SQLITE_DEBUG
VdbeComment(v, "Init subquery result");
#endif
}
else
{
dest.eDest = SRT_Exists;
sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iParm);
#if SQLITE_DEBUG
VdbeComment(v, "Init EXISTS result");
#endif
}
sqlite3ExprDelete(pParse.db, ref pSel.pLimit);
pSel.pLimit = sqlite3PExpr(pParse, TK_INTEGER, null, null, sqlite3IntTokens[1]);
pSel.iLimit = 0;
if (sqlite3Select(pParse, pSel, ref dest) != 0)
{
return 0;
}
rReg = dest.iParm;
ExprSetIrreducible(pExpr);
break;
}
}
if (testAddr != 0)
{
sqlite3VdbeJumpHere(v, testAddr - 1);
}
sqlite3ExprCachePop(pParse, 1);
return rReg;
}
#endif // * SQLITE_OMIT_SUBQUERY */
#if !SQLITE_OMIT_SUBQUERY
/*
** Generate code for an IN expression.
**
** x IN (SELECT ...)
** x IN (value, value, ...)
**
** The left-hand side (LHS) is a scalar expression. The right-hand side (RHS)
** is an array of zero or more values. The expression is true if the LHS is
** contained within the RHS. The value of the expression is unknown (NULL)
** if the LHS is NULL or if the LHS is not contained within the RHS and the
** RHS contains one or more NULL values.
**
** This routine generates code will jump to destIfFalse if the LHS is not
** contained within the RHS. If due to NULLs we cannot determine if the LHS
** is contained in the RHS then jump to destIfNull. If the LHS is contained
** within the RHS then fall through.
*/
private static void sqlite3ExprCodeIN(
Parse pParse, /* Parsing and code generating context */
Expr pExpr, /* The IN expression */
int destIfFalse, /* Jump here if LHS is not contained in the RHS */
int destIfNull /* Jump here if the results are unknown due to NULLs */
)
{
int rRhsHasNull = 0; /* Register that is true if RHS contains NULL values */
char affinity; /* Comparison affinity to use */
int eType; /* Type of the RHS */
int r1; /* Temporary use register */
Vdbe v; /* Statement under construction */
/* Compute the RHS. After this step, the table with cursor
** pExpr.iTable will contains the values that make up the RHS.
*/
v = pParse.pVdbe;
Debug.Assert(v != null); /* OOM detected prior to this routine */
VdbeNoopComment(v, "begin IN expr");
eType = sqlite3FindInIndex(pParse, pExpr, ref rRhsHasNull);
/* Figure out the affinity to use to create a key from the results
** of the expression. affinityStr stores a static string suitable for
** P4 of OP_MakeRecord.
*/
affinity = comparisonAffinity(pExpr);
/* Code the LHS, the <expr> from "<expr> IN (...)".
*/
sqlite3ExprCachePush(pParse);
r1 = sqlite3GetTempReg(pParse);
sqlite3ExprCode(pParse, pExpr.pLeft, r1);
/* If the LHS is NULL, then the result is either false or NULL depending
** on whether the RHS is empty or not, respectively.
*/
if (destIfNull == destIfFalse)
{
/* Shortcut for the common case where the false and NULL outcomes are
** the same. */
sqlite3VdbeAddOp2(v, OP_IsNull, r1, destIfNull);
}
else
{
int addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, r1);
sqlite3VdbeAddOp2(v, OP_Rewind, pExpr.iTable, destIfFalse);
sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull);
sqlite3VdbeJumpHere(v, addr1);
}
if (eType == IN_INDEX_ROWID)
{
/* In this case, the RHS is the ROWID of table b-tree
*/
sqlite3VdbeAddOp2(v, OP_MustBeInt, r1, destIfFalse);
sqlite3VdbeAddOp3(v, OP_NotExists, pExpr.iTable, destIfFalse, r1);
}
else
{
/* In this case, the RHS is an index b-tree.
*/
sqlite3VdbeAddOp4(v, OP_Affinity, r1, 1, 0, affinity, 1);
/* If the set membership test fails, then the result of the
** "x IN (...)" expression must be either 0 or NULL. If the set
** contains no NULL values, then the result is 0. If the set
** contains one or more NULL values, then the result of the
** expression is also NULL.
*/
if (rRhsHasNull == 0 || destIfFalse == destIfNull)
{
/* This branch runs if it is known at compile time that the RHS
** cannot contain NULL values. This happens as the result
** of a "NOT NULL" constraint in the database schema.
**
** Also run this branch if NULL is equivalent to FALSE
** for this particular IN operator.
*/
sqlite3VdbeAddOp4Int(v, OP_NotFound, pExpr.iTable, destIfFalse, r1, 1);
}
else
{
/* In this branch, the RHS of the IN might contain a NULL and
** the presence of a NULL on the RHS makes a difference in the
** outcome.
*/
int j1, j2, j3;
/* First check to see if the LHS is contained in the RHS. If so,
** then the presence of NULLs in the RHS does not matter, so jump
** over all of the code that follows.
*/
j1 = sqlite3VdbeAddOp4Int(v, OP_Found, pExpr.iTable, 0, r1, 1);
/* Here we begin generating code that runs if the LHS is not
** contained within the RHS. Generate additional code that
** tests the RHS for NULLs. If the RHS contains a NULL then
** jump to destIfNull. If there are no NULLs in the RHS then
** jump to destIfFalse.
*/
j2 = sqlite3VdbeAddOp1(v, OP_NotNull, rRhsHasNull);
j3 = sqlite3VdbeAddOp4Int(v, OP_Found, pExpr.iTable, 0, rRhsHasNull, 1);
sqlite3VdbeAddOp2(v, OP_Integer, -1, rRhsHasNull);
sqlite3VdbeJumpHere(v, j3);
sqlite3VdbeAddOp2(v, OP_AddImm, rRhsHasNull, 1);
sqlite3VdbeJumpHere(v, j2);
/* Jump to the appropriate target depending on whether or not
** the RHS contains a NULL
*/
sqlite3VdbeAddOp2(v, OP_If, rRhsHasNull, destIfNull);
sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfFalse);
/* The OP_Found at the top of this branch jumps here when true,
** causing the overall IN expression evaluation to fall through.
*/
sqlite3VdbeJumpHere(v, j1);
}
}
sqlite3ReleaseTempReg(pParse, r1);
sqlite3ExprCachePop(pParse, 1);
VdbeComment(v, "end IN expr");
}
#endif //* SQLITE_OMIT_SUBQUERY */
/*
** Duplicate an 8-byte value
*/
//static char *dup8bytes(Vdbe v, string in){
// char *out = sqlite3DbMallocRaw(sqlite3VdbeDb(v), 8);
// if( out ){
// memcpy(out, in, 8);
// }
// return out;
//}
#if !SQLITE_OMIT_FLOATING_POINT
/*
** Generate an instruction that will put the floating point
** value described by z[0..n-1] into register iMem.
**
** The z[] string will probably not be zero-terminated. But the
** z[n] character is guaranteed to be something that does not look
** like the continuation of the number.
*/
private static void codeReal(Vdbe v, string z, bool negateFlag, int iMem)
{
if (ALWAYS(!string.IsNullOrEmpty(z)))
{
double value = 0;
//string zV;
sqlite3AtoF(z, ref value, sqlite3Strlen30(z), SQLITE_UTF8);
Debug.Assert(!sqlite3IsNaN(value)); /* The new AtoF never returns NaN */
if (negateFlag)
value = -value;
//zV = dup8bytes(v, value);
sqlite3VdbeAddOp4(v, OP_Real, 0, iMem, 0, value, P4_REAL);
}
}
#endif
/*
** Generate an instruction that will put the integer describe by
** text z[0..n-1] into register iMem.
**
** Expr.u.zToken is always UTF8 and zero-terminated.
*/
private static void codeInteger(Parse pParse, Expr pExpr, bool negFlag, int iMem)
{
Vdbe v = pParse.pVdbe;
if ((pExpr.flags & EP_IntValue) != 0)
{
int i = pExpr.u.iValue;
Debug.Assert(i >= 0);
if (negFlag)
i = -i;
sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
}
else
{
int c;
i64 value = 0;
string z = pExpr.u.zToken;
Debug.Assert(!string.IsNullOrEmpty(z));
c = sqlite3Atoi64(z, ref value, sqlite3Strlen30(z), SQLITE_UTF8);
if (c == 0 || (c == 2 && negFlag))
{
//char* zV;
if (negFlag)
{
value = c == 2 ? SMALLEST_INT64 : -value;
}
sqlite3VdbeAddOp4(v, OP_Int64, 0, iMem, 0, value, P4_INT64);
}
else
{
#if SQLITE_OMIT_FLOATING_POINT
sqlite3ErrorMsg(pParse, "oversized integer: %s%s", negFlag ? "-" : string.Empty, z);
#else
codeReal(v, z, negFlag, iMem);
#endif
}
}
}
/*
** Clear a cache entry.
*/
private static void cacheEntryClear(Parse pParse, yColCache p)
{
if (p.tempReg != 0)
{
if (pParse.nTempReg < ArraySize(pParse.aTempReg))
{
pParse.aTempReg[pParse.nTempReg++] = p.iReg;
}
p.tempReg = 0;
}
}
/*
** Record in the column cache that a particular column from a
** particular table is stored in a particular register.
*/
private static void sqlite3ExprCacheStore(Parse pParse, int iTab, int iCol, int iReg)
{
int i;
int minLru;
int idxLru;
yColCache p = new yColCache();
Debug.Assert(iReg > 0); /* Register numbers are always positive */
Debug.Assert(iCol >= -1 && iCol < 32768); /* Finite column numbers */
/* The SQLITE_ColumnCache flag disables the column cache. This is used
** for testing only - to verify that SQLite always gets the same answer
** with and without the column cache.
*/
if ((pParse.db.flags & SQLITE_ColumnCache) != 0)
return;
/* First replace any existing entry.
**
** Actually, the way the column cache is currently used, we are guaranteed
** that the object will never already be in cache. Verify this guarantee.
*/
#if !NDEBUG
for (i = 0; i < SQLITE_N_COLCACHE; i++)//p=pParse.aColCache... p++)
{
#if FALSE //* This code wold remove the entry from the cache if it existed */
p = pParse.aColCache[i];
if ( p.iReg != 0 && p.iTable == iTab && p.iColumn == iCol )
{
cacheEntryClear( pParse, p );
p.iLevel = pParse.iCacheLevel;
p.iReg = iReg;
p.lru = pParse.iCacheCnt++;
return;
}
#endif
Debug.Assert(p.iReg == 0 || p.iTable != iTab || p.iColumn != iCol);
}
#endif
/* Find an empty slot and replace it */
for (i = 0; i < SQLITE_N_COLCACHE; i++)//p=pParse.aColCache... p++)
{
p = pParse.aColCache[i];
if (p.iReg == 0)
{
p.iLevel = pParse.iCacheLevel;
p.iTable = iTab;
p.iColumn = iCol;
p.iReg = iReg;
p.tempReg = 0;
p.lru = pParse.iCacheCnt++;
return;
}
}
/* Replace the last recently used */
minLru = 0x7fffffff;
idxLru = -1;
for (i = 0; i < SQLITE_N_COLCACHE; i++)//p=pParse.aColCache..., p++)
{
p = pParse.aColCache[i];
if (p.lru < minLru)
{
idxLru = i;
minLru = p.lru;
}
}
if (ALWAYS(idxLru >= 0))
{
p = pParse.aColCache[idxLru];
p.iLevel = pParse.iCacheLevel;
p.iTable = iTab;
p.iColumn = iCol;
p.iReg = iReg;
p.tempReg = 0;
p.lru = pParse.iCacheCnt++;
return;
}
}
/*
** Indicate that registers between iReg..iReg+nReg-1 are being overwritten.
** Purge the range of registers from the column cache.
*/
private static void sqlite3ExprCacheRemove(Parse pParse, int iReg, int nReg)
{
int i;
int iLast = iReg + nReg - 1;
yColCache p;
for (i = 0; i < SQLITE_N_COLCACHE; i++)//p=pParse.aColCache... p++)
{
p = pParse.aColCache[i];
int r = p.iReg;
if (r >= iReg && r <= iLast)
{
cacheEntryClear(pParse, p);
p.iReg = 0;
}
}
}
/*
** Remember the current column cache context. Any new entries added
** added to the column cache after this call are removed when the
** corresponding pop occurs.
*/
private static void sqlite3ExprCachePush(Parse pParse)
{
pParse.iCacheLevel++;
}
/*
** Remove from the column cache any entries that were added since the
** the previous N Push operations. In other words, restore the cache
** to the state it was in N Pushes ago.
*/
private static void sqlite3ExprCachePop(Parse pParse, int N)
{
int i;
yColCache p;
Debug.Assert(N > 0);
Debug.Assert(pParse.iCacheLevel >= N);
pParse.iCacheLevel -= N;
for (i = 0; i < SQLITE_N_COLCACHE; i++)// p++)
{
p = pParse.aColCache[i];
if (p.iReg != 0 && p.iLevel > pParse.iCacheLevel)
{
cacheEntryClear(pParse, p);
p.iReg = 0;
}
}
}
/*
** When a cached column is reused, make sure that its register is
** no longer available as a temp register. ticket #3879: that same
** register might be in the cache in multiple places, so be sure to
** get them all.
*/
private static void sqlite3ExprCachePinRegister(Parse pParse, int iReg)
{
int i;
yColCache p;
for (i = 0; i < SQLITE_N_COLCACHE; i++)//p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++)
{
p = pParse.aColCache[i];
if (p.iReg == iReg)
{
p.tempReg = 0;
}
}
}
/*
** Generate code to extract the value of the iCol-th column of a table.
*/
private static void sqlite3ExprCodeGetColumnOfTable(
Vdbe v, /* The VDBE under construction */
Table pTab, /* The table containing the value */
int iTabCur, /* The cursor for this table */
int iCol, /* Index of the column to extract */
int regOut /* Extract the value into this register */
)
{
if (iCol < 0 || iCol == pTab.iPKey)
{
sqlite3VdbeAddOp2(v, OP_Rowid, iTabCur, regOut);
}
else
{
int op = IsVirtual(pTab) ? OP_VColumn : OP_Column;
sqlite3VdbeAddOp3(v, op, iTabCur, iCol, regOut);
}
if (iCol >= 0)
{
sqlite3ColumnDefault(v, pTab, iCol, regOut);
}
}
/*
** Generate code that will extract the iColumn-th column from
** table pTab and store the column value in a register. An effort
** is made to store the column value in register iReg, but this is
** not guaranteed. The location of the column value is returned.
**
** There must be an open cursor to pTab in iTable when this routine
** is called. If iColumn<0 then code is generated that extracts the rowid.
*/
private static int sqlite3ExprCodeGetColumn(
Parse pParse, /* Parsing and code generating context */
Table pTab, /* Description of the table we are reading from */
int iColumn, /* Index of the table column */
int iTable, /* The cursor pointing to the table */
int iReg /* Store results here */
)
{
Vdbe v = pParse.pVdbe;
int i;
yColCache p;
for (i = 0; i < SQLITE_N_COLCACHE; i++)
{// p=pParse.aColCache, p++
p = pParse.aColCache[i];
if (p.iReg > 0 && p.iTable == iTable && p.iColumn == iColumn)
{
p.lru = pParse.iCacheCnt++;
sqlite3ExprCachePinRegister(pParse, p.iReg);
return p.iReg;
}
}
Debug.Assert(v != null);
sqlite3ExprCodeGetColumnOfTable(v, pTab, iTable, iColumn, iReg);
sqlite3ExprCacheStore(pParse, iTable, iColumn, iReg);
return iReg;
}
/*
** Clear all column cache entries.
*/
private static void sqlite3ExprCacheClear(Parse pParse)
{
int i;
yColCache p;
for (i = 0; i < SQLITE_N_COLCACHE; i++)// p=pParse.aColCache... p++)
{
p = pParse.aColCache[i];
if (p.iReg != 0)
{
cacheEntryClear(pParse, p);
p.iReg = 0;
}
}
}
/*
** Record the fact that an affinity change has occurred on iCount
** registers starting with iStart.
*/
private static void sqlite3ExprCacheAffinityChange(Parse pParse, int iStart, int iCount)
{
sqlite3ExprCacheRemove(pParse, iStart, iCount);
}
/*
** Generate code to move content from registers iFrom...iFrom+nReg-1
** over to iTo..iTo+nReg-1. Keep the column cache up-to-date.
*/
private static void sqlite3ExprCodeMove(Parse pParse, int iFrom, int iTo, int nReg)
{
int i;
yColCache p;
if (NEVER(iFrom == iTo))
return;
sqlite3VdbeAddOp3(pParse.pVdbe, OP_Move, iFrom, iTo, nReg);
for (i = 0; i < SQLITE_N_COLCACHE; i++)// p=pParse.aColCache... p++)
{
p = pParse.aColCache[i];
int x = p.iReg;
if (x >= iFrom && x < iFrom + nReg)
{
p.iReg += iTo - iFrom;
}
}
}
/*
** Generate code to copy content from registers iFrom...iFrom+nReg-1
** over to iTo..iTo+nReg-1.
*/
private static void sqlite3ExprCodeCopy(Parse pParse, int iFrom, int iTo, int nReg)
{
int i;
if (NEVER(iFrom == iTo))
return;
for (i = 0; i < nReg; i++)
{
sqlite3VdbeAddOp2(pParse.pVdbe, OP_Copy, iFrom + i, iTo + i);
}
}
#if (SQLITE_DEBUG) || (SQLITE_COVERAGE_TEST)
/*
** Return true if any register in the range iFrom..iTo (inclusive)
** is used as part of the column cache.
**
** This routine is used within Debug.Assert() and testcase() macros only
** and does not appear in a normal build.
*/
private static int usedAsColumnCache(Parse pParse, int iFrom, int iTo)
{
int i;
yColCache p;
for (i = 0; i < SQLITE_N_COLCACHE; i++)//p=pParse.aColCache... p++)
{
p = pParse.aColCache[i];
int r = p.iReg;
if (r >= iFrom && r <= iTo)
return 1; /*NO_TEST*/
}
return 0;
}
#else
static int usedAsColumnCache( Parse pParse, int iFrom, int iTo ){return 0;}
#endif //* SQLITE_DEBUG || SQLITE_COVERAGE_TEST */
/*
** Generate code into the current Vdbe to evaluate the given
** expression. Attempt to store the results in register "target".
** Return the register where results are stored.
**
** With this routine, there is no guarantee that results will
** be stored in target. The result might be stored in some other
** register if it is convenient to do so. The calling function
** must check the return code and move the results to the desired
** register.
*/
private static int sqlite3ExprCodeTarget(Parse pParse, Expr pExpr, int target)
{
Vdbe v = pParse.pVdbe; /* The VM under construction */
int op; /* The opcode being coded */
int inReg = target; /* Results stored in register inReg */
int regFree1 = 0; /* If non-zero free this temporary register */
int regFree2 = 0; /* If non-zero free this temporary register */
int r1 = 0, r2 = 0, r3 = 0, r4 = 0; /* Various register numbers */
sqlite3 db = pParse.db; /* The database connection */
Debug.Assert(target > 0 && target <= pParse.nMem);
if (v == null)
{
//Debug.Assert( pParse.db.mallocFailed != 0 );
return 0;
}
if (pExpr == null)
{
op = TK_NULL;
}
else
{
op = pExpr.op;
}
switch (op)
{
case TK_AGG_COLUMN:
{
AggInfo pAggInfo = pExpr.pAggInfo;
AggInfo_col pCol = pAggInfo.aCol[pExpr.iAgg];
if (pAggInfo.directMode == 0)
{
Debug.Assert(pCol.iMem > 0);
inReg = pCol.iMem;
break;
}
else if (pAggInfo.useSortingIdx != 0)
{
sqlite3VdbeAddOp3(v, OP_Column, pAggInfo.sortingIdx,
pCol.iSorterColumn, target);
break;
}
/* Otherwise, fall thru into the TK_COLUMN case */
}
goto case TK_COLUMN;
case TK_COLUMN:
{
if (pExpr.iTable < 0)
{
/* This only happens when coding check constraints */
Debug.Assert(pParse.ckBase > 0);
inReg = pExpr.iColumn + pParse.ckBase;
}
else
{
inReg = sqlite3ExprCodeGetColumn(pParse, pExpr.pTab,
pExpr.iColumn, pExpr.iTable, target);
}
break;
}
case TK_INTEGER:
{
codeInteger(pParse, pExpr, false, target);
break;
}
#if !SQLITE_OMIT_FLOATING_POINT
case TK_FLOAT:
{
Debug.Assert(!ExprHasProperty(pExpr, EP_IntValue));
codeReal(v, pExpr.u.zToken, false, target);
break;
}
#endif
case TK_STRING:
{
Debug.Assert(!ExprHasProperty(pExpr, EP_IntValue));
sqlite3VdbeAddOp4(v, OP_String8, 0, target, 0, pExpr.u.zToken, 0);
break;
}
case TK_NULL:
{
sqlite3VdbeAddOp2(v, OP_Null, 0, target);
break;
}
#if !SQLITE_OMIT_BLOB_LITERAL
case TK_BLOB:
{
int n;
string z;
byte[] zBlob;
Debug.Assert(!ExprHasProperty(pExpr, EP_IntValue));
Debug.Assert(pExpr.u.zToken[0] == 'x' || pExpr.u.zToken[0] == 'X');
Debug.Assert(pExpr.u.zToken[1] == '\'');
z = pExpr.u.zToken.Substring(2);
n = sqlite3Strlen30(z) - 1;
Debug.Assert(z[n] == '\'');
zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n);
sqlite3VdbeAddOp4(v, OP_Blob, n / 2, target, 0, zBlob, P4_DYNAMIC);
break;
}
#endif
case TK_VARIABLE:
{
Debug.Assert(!ExprHasProperty(pExpr, EP_IntValue));
Debug.Assert(pExpr.u.zToken != null);
Debug.Assert(pExpr.u.zToken.Length != 0);
sqlite3VdbeAddOp2(v, OP_Variable, pExpr.iColumn, target);
if (pExpr.u.zToken.Length > 1)
{
Debug.Assert(pExpr.u.zToken[0] == '?'
|| pExpr.u.zToken.CompareTo(pParse.azVar[pExpr.iColumn - 1]) == 0);
sqlite3VdbeChangeP4(v, -1, pParse.azVar[pExpr.iColumn - 1], P4_STATIC);
}
break;
}
case TK_REGISTER:
{
inReg = pExpr.iTable;
break;
}
case TK_AS:
{
inReg = sqlite3ExprCodeTarget(pParse, pExpr.pLeft, target);
break;
}
#if !SQLITE_OMIT_CAST
case TK_CAST:
{
/* Expressions of the form: CAST(pLeft AS token) */
int aff, to_op;
inReg = sqlite3ExprCodeTarget(pParse, pExpr.pLeft, target);
Debug.Assert(!ExprHasProperty(pExpr, EP_IntValue));
aff = sqlite3AffinityType(pExpr.u.zToken);
to_op = aff - SQLITE_AFF_TEXT + OP_ToText;
Debug.Assert(to_op == OP_ToText || aff != SQLITE_AFF_TEXT);
Debug.Assert(to_op == OP_ToBlob || aff != SQLITE_AFF_NONE);
Debug.Assert(to_op == OP_ToNumeric || aff != SQLITE_AFF_NUMERIC);
Debug.Assert(to_op == OP_ToInt || aff != SQLITE_AFF_INTEGER);
Debug.Assert(to_op == OP_ToReal || aff != SQLITE_AFF_REAL);
testcase(to_op == OP_ToText);
testcase(to_op == OP_ToBlob);
testcase(to_op == OP_ToNumeric);
testcase(to_op == OP_ToInt);
testcase(to_op == OP_ToReal);
if (inReg != target)
{
sqlite3VdbeAddOp2(v, OP_SCopy, inReg, target);
inReg = target;
}
sqlite3VdbeAddOp1(v, to_op, inReg);
testcase(usedAsColumnCache(pParse, inReg, inReg) != 0);
sqlite3ExprCacheAffinityChange(pParse, inReg, 1);
break;
}
#endif // * SQLITE_OMIT_CAST */
case TK_LT:
case TK_LE:
case TK_GT:
case TK_GE:
case TK_NE:
case TK_EQ:
{
Debug.Assert(TK_LT == OP_Lt);
Debug.Assert(TK_LE == OP_Le);
Debug.Assert(TK_GT == OP_Gt);
Debug.Assert(TK_GE == OP_Ge);
Debug.Assert(TK_EQ == OP_Eq);
Debug.Assert(TK_NE == OP_Ne);
testcase(op == TK_LT);
testcase(op == TK_LE);
testcase(op == TK_GT);
testcase(op == TK_GE);
testcase(op == TK_EQ);
testcase(op == TK_NE);
r1 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree1);
r2 = sqlite3ExprCodeTemp(pParse, pExpr.pRight, ref regFree2);
codeCompare(pParse, pExpr.pLeft, pExpr.pRight, op,
r1, r2, inReg, SQLITE_STOREP2);
testcase(regFree1 == 0);
testcase(regFree2 == 0);
break;
}
case TK_IS:
case TK_ISNOT:
{
testcase(op == TK_IS);
testcase(op == TK_ISNOT);
r1 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree1);
r2 = sqlite3ExprCodeTemp(pParse, pExpr.pRight, ref regFree2);
op = (op == TK_IS) ? TK_EQ : TK_NE;
codeCompare(pParse, pExpr.pLeft, pExpr.pRight, op,
r1, r2, inReg, SQLITE_STOREP2 | SQLITE_NULLEQ);
testcase(regFree1 == 0);
testcase(regFree2 == 0);
break;
}
case TK_AND:
case TK_OR:
case TK_PLUS:
case TK_STAR:
case TK_MINUS:
case TK_REM:
case TK_BITAND:
case TK_BITOR:
case TK_SLASH:
case TK_LSHIFT:
case TK_RSHIFT:
case TK_CONCAT:
{
Debug.Assert(TK_AND == OP_And);
Debug.Assert(TK_OR == OP_Or);
Debug.Assert(TK_PLUS == OP_Add);
Debug.Assert(TK_MINUS == OP_Subtract);
Debug.Assert(TK_REM == OP_Remainder);
Debug.Assert(TK_BITAND == OP_BitAnd);
Debug.Assert(TK_BITOR == OP_BitOr);
Debug.Assert(TK_SLASH == OP_Divide);
Debug.Assert(TK_LSHIFT == OP_ShiftLeft);
Debug.Assert(TK_RSHIFT == OP_ShiftRight);
Debug.Assert(TK_CONCAT == OP_Concat);
testcase(op == TK_AND);
testcase(op == TK_OR);
testcase(op == TK_PLUS);
testcase(op == TK_MINUS);
testcase(op == TK_REM);
testcase(op == TK_BITAND);
testcase(op == TK_BITOR);
testcase(op == TK_SLASH);
testcase(op == TK_LSHIFT);
testcase(op == TK_RSHIFT);
testcase(op == TK_CONCAT);
r1 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree1);
r2 = sqlite3ExprCodeTemp(pParse, pExpr.pRight, ref regFree2);
sqlite3VdbeAddOp3(v, op, r2, r1, target);
testcase(regFree1 == 0);
testcase(regFree2 == 0);
break;
}
case TK_UMINUS:
{
Expr pLeft = pExpr.pLeft;
Debug.Assert(pLeft != null);
if (pLeft.op == TK_INTEGER)
{
codeInteger(pParse, pLeft, true, target);
#if !SQLITE_OMIT_FLOATING_POINT
}
else if (pLeft.op == TK_FLOAT)
{
Debug.Assert(!ExprHasProperty(pExpr, EP_IntValue));
codeReal(v, pLeft.u.zToken, true, target);
#endif
}
else
{
regFree1 = r1 = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_Integer, 0, r1);
r2 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree2);
sqlite3VdbeAddOp3(v, OP_Subtract, r2, r1, target);
testcase(regFree2 == 0);
}
inReg = target;
break;
}
case TK_BITNOT:
case TK_NOT:
{
Debug.Assert(TK_BITNOT == OP_BitNot);
Debug.Assert(TK_NOT == OP_Not);
testcase(op == TK_BITNOT);
testcase(op == TK_NOT);
r1 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree1);
testcase(regFree1 == 0);
inReg = target;
sqlite3VdbeAddOp2(v, op, r1, inReg);
break;
}
case TK_ISNULL:
case TK_NOTNULL:
{
int addr;
Debug.Assert(TK_ISNULL == OP_IsNull);
Debug.Assert(TK_NOTNULL == OP_NotNull);
testcase(op == TK_ISNULL);
testcase(op == TK_NOTNULL);
sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
r1 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree1);
testcase(regFree1 == 0);
addr = sqlite3VdbeAddOp1(v, op, r1);
sqlite3VdbeAddOp2(v, OP_AddImm, target, -1);
sqlite3VdbeJumpHere(v, addr);
break;
}
case TK_AGG_FUNCTION:
{
AggInfo pInfo = pExpr.pAggInfo;
if (pInfo == null)
{
Debug.Assert(!ExprHasProperty(pExpr, EP_IntValue));
sqlite3ErrorMsg(pParse, "misuse of aggregate: %s()", pExpr.u.zToken);
}
else
{
inReg = pInfo.aFunc[pExpr.iAgg].iMem;
}
break;
}
case TK_CONST_FUNC:
case TK_FUNCTION:
{
ExprList pFarg; /* List of function arguments */
int nFarg; /* Number of function arguments */
FuncDef pDef; /* The function definition object */
int nId; /* Length of the function name in bytes */
string zId; /* The function name */
int constMask = 0; /* Mask of function arguments that are constant */
int i; /* Loop counter */
u8 enc = ENC(db); /* The text encoding used by this database */
CollSeq pColl = null; /* A collating sequence */
Debug.Assert(!ExprHasProperty(pExpr, EP_xIsSelect));
testcase(op == TK_CONST_FUNC);
testcase(op == TK_FUNCTION);
if (ExprHasAnyProperty(pExpr, EP_TokenOnly))
{
pFarg = null;
}
else
{
pFarg = pExpr.x.pList;
}
nFarg = pFarg != null ? pFarg.nExpr : 0;
Debug.Assert(!ExprHasProperty(pExpr, EP_IntValue));
zId = pExpr.u.zToken;
nId = sqlite3Strlen30(zId);
pDef = sqlite3FindFunction(pParse.db, zId, nId, nFarg, enc, 0);
if (pDef == null)
{
sqlite3ErrorMsg(pParse, "unknown function: %.*s()", nId, zId);
break;
}
/* Attempt a direct implementation of the built-in COALESCE() and
** IFNULL() functions. This avoids unnecessary evalation of
** arguments past the first non-NULL argument.
*/
if ((pDef.flags & SQLITE_FUNC_COALESCE) != 0)
{
int endCoalesce = sqlite3VdbeMakeLabel(v);
Debug.Assert(nFarg >= 2);
sqlite3ExprCode(pParse, pFarg.a[0].pExpr, target);
for (i = 1; i < nFarg; i++)
{
sqlite3VdbeAddOp2(v, OP_NotNull, target, endCoalesce);
sqlite3ExprCacheRemove(pParse, target, 1);
sqlite3ExprCachePush(pParse);
sqlite3ExprCode(pParse, pFarg.a[i].pExpr, target);
sqlite3ExprCachePop(pParse, 1);
}
sqlite3VdbeResolveLabel(v, endCoalesce);
break;
}
if (pFarg != null)
{
r1 = sqlite3GetTempRange(pParse, nFarg);
sqlite3ExprCachePush(pParse); /* Ticket 2ea2425d34be */
sqlite3ExprCodeExprList(pParse, pFarg, r1, true);
sqlite3ExprCachePop(pParse, 1); /* Ticket 2ea2425d34be */
}
else
{
r1 = 0;
}
#if !SQLITE_OMIT_VIRTUALTABLE
/* Possibly overload the function if the first argument is
** a virtual table column.
**
** For infix functions (LIKE, GLOB, REGEXP, and MATCH) use the
** second argument, not the first, as the argument to test to
** see if it is a column in a virtual table. This is done because
** the left operand of infix functions (the operand we want to
** control overloading) ends up as the second argument to the
** function. The expression "A glob B" is equivalent to
** "glob(B,A). We want to use the A in "A glob B" to test
** for function overloading. But we use the B term in "glob(B,A)".
*/
if (nFarg >= 2 && (pExpr.flags & EP_InfixFunc) != 0)
{
pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg.a[1].pExpr);
}
else if (nFarg > 0)
{
pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg.a[0].pExpr);
}
#endif
for (i = 0; i < nFarg; i++)
{
if (i < 32 && sqlite3ExprIsConstant(pFarg.a[i].pExpr) != 0)
{
constMask |= (1 << i);
}
if ((pDef.flags & SQLITE_FUNC_NEEDCOLL) != 0 && null == pColl)
{
pColl = sqlite3ExprCollSeq(pParse, pFarg.a[i].pExpr);
}
}
if ((pDef.flags & SQLITE_FUNC_NEEDCOLL) != 0)
{
if (null == pColl)
pColl = db.pDfltColl;
sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, pColl, P4_COLLSEQ);
}
sqlite3VdbeAddOp4(v, OP_Function, constMask, r1, target,
pDef, P4_FUNCDEF);
sqlite3VdbeChangeP5(v, (u8)nFarg);
if (nFarg != 0)
{
sqlite3ReleaseTempRange(pParse, r1, nFarg);
}
break;
}
#if !SQLITE_OMIT_SUBQUERY
case TK_EXISTS:
case TK_SELECT:
{
testcase(op == TK_EXISTS);
testcase(op == TK_SELECT);
inReg = sqlite3CodeSubselect(pParse, pExpr, 0, false);
break;
}
case TK_IN:
{
int destIfFalse = sqlite3VdbeMakeLabel(v);
int destIfNull = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp2(v, OP_Null, 0, target);
sqlite3ExprCodeIN(pParse, pExpr, destIfFalse, destIfNull);
sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
sqlite3VdbeResolveLabel(v, destIfFalse);
sqlite3VdbeAddOp2(v, OP_AddImm, target, 0);
sqlite3VdbeResolveLabel(v, destIfNull);
break;
}
#endif //* SQLITE_OMIT_SUBQUERY */
/*
** x BETWEEN y AND z
**
** This is equivalent to
**
** x>=y AND x<=z
**
** X is stored in pExpr.pLeft.
** Y is stored in pExpr.x.pList.a[0].pExpr.
** Z is stored in pExpr.x.pList.a[1].pExpr.
*/
case TK_BETWEEN:
{
Expr pLeft = pExpr.pLeft;
ExprList_item pLItem = pExpr.x.pList.a[0];
Expr pRight = pLItem.pExpr;
r1 = sqlite3ExprCodeTemp(pParse, pLeft, ref regFree1);
r2 = sqlite3ExprCodeTemp(pParse, pRight, ref regFree2);
testcase(regFree1 == 0);
testcase(regFree2 == 0);
r3 = sqlite3GetTempReg(pParse);
r4 = sqlite3GetTempReg(pParse);
codeCompare(pParse, pLeft, pRight, OP_Ge,
r1, r2, r3, SQLITE_STOREP2);
pLItem = pExpr.x.pList.a[1];// pLItem++;
pRight = pLItem.pExpr;
sqlite3ReleaseTempReg(pParse, regFree2);
r2 = sqlite3ExprCodeTemp(pParse, pRight, ref regFree2);
testcase(regFree2 == 0);
codeCompare(pParse, pLeft, pRight, OP_Le, r1, r2, r4, SQLITE_STOREP2);
sqlite3VdbeAddOp3(v, OP_And, r3, r4, target);
sqlite3ReleaseTempReg(pParse, r3);
sqlite3ReleaseTempReg(pParse, r4);
break;
}
case TK_UPLUS:
{
inReg = sqlite3ExprCodeTarget(pParse, pExpr.pLeft, target);
break;
}
case TK_TRIGGER:
{
/* If the opcode is TK_TRIGGER, then the expression is a reference
** to a column in the new.* or old.* pseudo-tables available to
** trigger programs. In this case Expr.iTable is set to 1 for the
** new.* pseudo-table, or 0 for the old.* pseudo-table. Expr.iColumn
** is set to the column of the pseudo-table to read, or to -1 to
** read the rowid field.
**
** The expression is implemented using an OP_Param opcode. The p1
** parameter is set to 0 for an old.rowid reference, or to (i+1)
** to reference another column of the old.* pseudo-table, where
** i is the index of the column. For a new.rowid reference, p1 is
** set to (n+1), where n is the number of columns in each pseudo-table.
** For a reference to any other column in the new.* pseudo-table, p1
** is set to (n+2+i), where n and i are as defined previously. For
** example, if the table on which triggers are being fired is
** declared as:
**
** CREATE TABLE t1(a, b);
**
** Then p1 is interpreted as follows:
**
** p1==0 . old.rowid p1==3 . new.rowid
** p1==1 . old.a p1==4 . new.a
** p1==2 . old.b p1==5 . new.b
*/
Table pTab = pExpr.pTab;
int p1 = pExpr.iTable * (pTab.nCol + 1) + 1 + pExpr.iColumn;
Debug.Assert(pExpr.iTable == 0 || pExpr.iTable == 1);
Debug.Assert(pExpr.iColumn >= -1 && pExpr.iColumn < pTab.nCol);
Debug.Assert(pTab.iPKey < 0 || pExpr.iColumn != pTab.iPKey);
Debug.Assert(p1 >= 0 && p1 < (pTab.nCol * 2 + 2));
sqlite3VdbeAddOp2(v, OP_Param, p1, target);
VdbeComment(v, "%s.%s -> $%d",
(pExpr.iTable != 0 ? "new" : "old"),
(pExpr.iColumn < 0 ? "rowid" : pExpr.pTab.aCol[pExpr.iColumn].zName),
target
);
/* If the column has REAL affinity, it may currently be stored as an
** integer. Use OP_RealAffinity to make sure it is really real. */
if (pExpr.iColumn >= 0
&& pTab.aCol[pExpr.iColumn].affinity == SQLITE_AFF_REAL
)
{
sqlite3VdbeAddOp1(v, OP_RealAffinity, target);
}
break;
}
/*
** Form A:
** CASE x WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
**
** Form B:
** CASE WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
**
** Form A is can be transformed into the equivalent form B as follows:
** CASE WHEN x=e1 THEN r1 WHEN x=e2 THEN r2 ...
** WHEN x=eN THEN rN ELSE y END
**
** X (if it exists) is in pExpr.pLeft.
** Y is in pExpr.pRight. The Y is also optional. If there is no
** ELSE clause and no other term matches, then the result of the
** exprssion is NULL.
** Ei is in pExpr.x.pList.a[i*2] and Ri is pExpr.x.pList.a[i*2+1].
**
** The result of the expression is the Ri for the first matching Ei,
** or if there is no matching Ei, the ELSE term Y, or if there is
** no ELSE term, NULL.
*/
default:
{
Debug.Assert(op == TK_CASE);
int endLabel; /* GOTO label for end of CASE stmt */
int nextCase; /* GOTO label for next WHEN clause */
int nExpr; /* 2x number of WHEN terms */
int i; /* Loop counter */
ExprList pEList; /* List of WHEN terms */
ExprList_item[] aListelem; /* Array of WHEN terms */
Expr opCompare = new Expr(); /* The X==Ei expression */
Expr cacheX; /* Cached expression X */
Expr pX; /* The X expression */
Expr pTest = null; /* X==Ei (form A) or just Ei (form B) */
#if !NDEBUG
int iCacheLevel = pParse.iCacheLevel;
//VVA_ONLY( int iCacheLevel = pParse.iCacheLevel; )
#endif
Debug.Assert(!ExprHasProperty(pExpr, EP_xIsSelect) && pExpr.x.pList != null);
Debug.Assert((pExpr.x.pList.nExpr % 2) == 0);
Debug.Assert(pExpr.x.pList.nExpr > 0);
pEList = pExpr.x.pList;
aListelem = pEList.a;
nExpr = pEList.nExpr;
endLabel = sqlite3VdbeMakeLabel(v);
if ((pX = pExpr.pLeft) != null)
{
cacheX = pX;
testcase(pX.op == TK_COLUMN);
testcase(pX.op == TK_REGISTER);
cacheX.iTable = sqlite3ExprCodeTemp(pParse, pX, ref regFree1);
testcase(regFree1 == 0);
cacheX.op = TK_REGISTER;
opCompare.op = TK_EQ;
opCompare.pLeft = cacheX;
pTest = opCompare;
/* Ticket b351d95f9cd5ef17e9d9dbae18f5ca8611190001:
** The value in regFree1 might get SCopy-ed into the file result.
** So make sure that the regFree1 register is not reused for other
** purposes and possibly overwritten. */
regFree1 = 0;
}
for (i = 0; i < nExpr; i = i + 2)
{
sqlite3ExprCachePush(pParse);
if (pX != null)
{
Debug.Assert(pTest != null);
opCompare.pRight = aListelem[i].pExpr;
}
else
{
pTest = aListelem[i].pExpr;
}
nextCase = sqlite3VdbeMakeLabel(v);
testcase(pTest.op == TK_COLUMN);
sqlite3ExprIfFalse(pParse, pTest, nextCase, SQLITE_JUMPIFNULL);
testcase(aListelem[i + 1].pExpr.op == TK_COLUMN);
testcase(aListelem[i + 1].pExpr.op == TK_REGISTER);
sqlite3ExprCode(pParse, aListelem[i + 1].pExpr, target);
sqlite3VdbeAddOp2(v, OP_Goto, 0, endLabel);
sqlite3ExprCachePop(pParse, 1);
sqlite3VdbeResolveLabel(v, nextCase);
}
if (pExpr.pRight != null)
{
sqlite3ExprCachePush(pParse);
sqlite3ExprCode(pParse, pExpr.pRight, target);
sqlite3ExprCachePop(pParse, 1);
}
else
{
sqlite3VdbeAddOp2(v, OP_Null, 0, target);
}
#if !NDEBUG
Debug.Assert( /* db.mallocFailed != 0 || */ pParse.nErr > 0
|| pParse.iCacheLevel == iCacheLevel);
#endif
sqlite3VdbeResolveLabel(v, endLabel);
break;
}
#if !SQLITE_OMIT_TRIGGER
case TK_RAISE:
{
Debug.Assert(pExpr.affinity == OE_Rollback
|| pExpr.affinity == OE_Abort
|| pExpr.affinity == OE_Fail
|| pExpr.affinity == OE_Ignore
);
if (null == pParse.pTriggerTab)
{
sqlite3ErrorMsg(pParse,
"RAISE() may only be used within a trigger-program");
return 0;
}
if (pExpr.affinity == OE_Abort)
{
sqlite3MayAbort(pParse);
}
Debug.Assert(!ExprHasProperty(pExpr, EP_IntValue));
if (pExpr.affinity == OE_Ignore)
{
sqlite3VdbeAddOp4(
v, OP_Halt, SQLITE_OK, OE_Ignore, 0, pExpr.u.zToken, 0);
}
else
{
sqlite3HaltConstraint(pParse, pExpr.affinity, pExpr.u.zToken, 0);
}
break;
}
#endif
}
sqlite3ReleaseTempReg(pParse, regFree1);
sqlite3ReleaseTempReg(pParse, regFree2);
return inReg;
}
/*
** Generate code to evaluate an expression and store the results
** into a register. Return the register number where the results
** are stored.
**
** If the register is a temporary register that can be deallocated,
** then write its number into pReg. If the result register is not
** a temporary, then set pReg to zero.
*/
private static int sqlite3ExprCodeTemp(Parse pParse, Expr pExpr, ref int pReg)
{
int r1 = sqlite3GetTempReg(pParse);
int r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
if (r2 == r1)
{
pReg = r1;
}
else
{
sqlite3ReleaseTempReg(pParse, r1);
pReg = 0;
}
return r2;
}
/*
** Generate code that will evaluate expression pExpr and store the
** results in register target. The results are guaranteed to appear
** in register target.
*/
private static int sqlite3ExprCode(Parse pParse, Expr pExpr, int target)
{
int inReg;
Debug.Assert(target > 0 && target <= pParse.nMem);
if (pExpr != null && pExpr.op == TK_REGISTER)
{
sqlite3VdbeAddOp2(pParse.pVdbe, OP_Copy, pExpr.iTable, target);
}
else
{
inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
Debug.Assert(pParse.pVdbe != null /* || pParse.db.mallocFailed != 0 */ );
if (inReg != target && pParse.pVdbe != null)
{
sqlite3VdbeAddOp2(pParse.pVdbe, OP_SCopy, inReg, target);
}
}
return target;
}
/*
** Generate code that evalutes the given expression and puts the result
** in register target.
**
** Also make a copy of the expression results into another "cache" register
** and modify the expression so that the next time it is evaluated,
** the result is a copy of the cache register.
**
** This routine is used for expressions that are used multiple
** times. They are evaluated once and the results of the expression
** are reused.
*/
private static int sqlite3ExprCodeAndCache(Parse pParse, Expr pExpr, int target)
{
Vdbe v = pParse.pVdbe;
int inReg;
inReg = sqlite3ExprCode(pParse, pExpr, target);
Debug.Assert(target > 0);
/* This routine is called for terms to INSERT or UPDATE. And the only
** other place where expressions can be converted into TK_REGISTER is
** in WHERE clause processing. So as currently implemented, there is
** no way for a TK_REGISTER to exist here. But it seems prudent to
** keep the ALWAYS() in case the conditions above change with future
** modifications or enhancements. */
if (ALWAYS(pExpr.op != TK_REGISTER))
{
int iMem;
iMem = ++pParse.nMem;
sqlite3VdbeAddOp2(v, OP_Copy, inReg, iMem);
pExpr.iTable = iMem;
pExpr.op2 = pExpr.op;
pExpr.op = TK_REGISTER;
}
return inReg;
}
/*
** Return TRUE if pExpr is an constant expression that is appropriate
** for factoring out of a loop. Appropriate expressions are:
**
** * Any expression that evaluates to two or more opcodes.
**
** * Any OP_Integer, OP_Real, OP_String, OP_Blob, OP_Null,
** or OP_Variable that does not need to be placed in a
** specific register.
**
** There is no point in factoring out single-instruction constant
** expressions that need to be placed in a particular register.
** We could factor them out, but then we would end up adding an
** OP_SCopy instruction to move the value into the correct register
** later. We might as well just use the original instruction and
** avoid the OP_SCopy.
*/
private static int isAppropriateForFactoring(Expr p)
{
if (sqlite3ExprIsConstantNotJoin(p) == 0)
{
return 0; /* Only constant expressions are appropriate for factoring */
}
if ((p.flags & EP_FixedDest) == 0)
{
return 1; /* Any constant without a fixed destination is appropriate */
}
while (p.op == TK_UPLUS)
p = p.pLeft;
switch (p.op)
{
#if !SQLITE_OMIT_BLOB_LITERAL
case TK_BLOB:
#endif
case TK_VARIABLE:
case TK_INTEGER:
case TK_FLOAT:
case TK_NULL:
case TK_STRING:
{
testcase(p.op == TK_BLOB);
testcase(p.op == TK_VARIABLE);
testcase(p.op == TK_INTEGER);
testcase(p.op == TK_FLOAT);
testcase(p.op == TK_NULL);
testcase(p.op == TK_STRING);
/* Single-instruction constants with a fixed destination are
** better done in-line. If we factor them, they will just end
** up generating an OP_SCopy to move the value to the destination
** register. */
return 0;
}
case TK_UMINUS:
{
if (p.pLeft.op == TK_FLOAT || p.pLeft.op == TK_INTEGER)
{
return 0;
}
break;
}
default:
{
break;
}
}
return 1;
}
/*
** If pExpr is a constant expression that is appropriate for
** factoring out of a loop, then evaluate the expression
** into a register and convert the expression into a TK_REGISTER
** expression.
*/
private static int evalConstExpr(Walker pWalker, ref Expr pExpr)
{
Parse pParse = pWalker.pParse;
switch (pExpr.op)
{
case TK_IN:
case TK_REGISTER:
{
return WRC_Prune;
}
case TK_FUNCTION:
case TK_AGG_FUNCTION:
case TK_CONST_FUNC:
{
/* The arguments to a function have a fixed destination.
** Mark them this way to avoid generated unneeded OP_SCopy
** instructions.
*/
ExprList pList = pExpr.x.pList;
Debug.Assert(!ExprHasProperty(pExpr, EP_xIsSelect));
if (pList != null)
{
int i = pList.nExpr;
ExprList_item pItem;//= pList.a;
for (; i > 0; i--)
{//, pItem++){
pItem = pList.a[pList.nExpr - i];
if (ALWAYS(pItem.pExpr != null))
pItem.pExpr.flags |= EP_FixedDest;
}
}
break;
}
}
if (isAppropriateForFactoring(pExpr) != 0)
{
int r1 = ++pParse.nMem;
int r2;
r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
if (NEVER(r1 != r2))
sqlite3ReleaseTempReg(pParse, r1);
pExpr.op2 = pExpr.op;
pExpr.op = TK_REGISTER;
pExpr.iTable = r2;
return WRC_Prune;
}
return WRC_Continue;
}
/*
** Preevaluate constant subexpressions within pExpr and store the
** results in registers. Modify pExpr so that the constant subexpresions
** are TK_REGISTER opcodes that refer to the precomputed values.
**
** This routine is a no-op if the jump to the cookie-check code has
** already occur. Since the cookie-check jump is generated prior to
** any other serious processing, this check ensures that there is no
** way to accidently bypass the constant initializations.
**
** This routine is also a no-op if the SQLITE_FactorOutConst optimization
** is disabled via the sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS)
** interface. This allows test logic to verify that the same answer is
** obtained for queries regardless of whether or not constants are
** precomputed into registers or if they are inserted in-line.
*/
private static void sqlite3ExprCodeConstants(Parse pParse, Expr pExpr)
{
Walker w;
if (pParse.cookieGoto != 0)
return;
if ((pParse.db.flags & SQLITE_FactorOutConst) != 0)
return;
w = new Walker();
w.xExprCallback = (dxExprCallback)evalConstExpr;
w.xSelectCallback = null;
w.pParse = pParse;
sqlite3WalkExpr(w, ref pExpr);
}
/*
** Generate code that pushes the value of every element of the given
** expression list into a sequence of registers beginning at target.
**
** Return the number of elements evaluated.
*/
private static int sqlite3ExprCodeExprList(
Parse pParse, /* Parsing context */
ExprList pList, /* The expression list to be coded */
int target, /* Where to write results */
bool doHardCopy /* Make a hard copy of every element */
)
{
ExprList_item pItem;
int i, n;
Debug.Assert(pList != null);
Debug.Assert(target > 0);
Debug.Assert(pParse.pVdbe != null); /* Never gets this far otherwise */
n = pList.nExpr;
for (i = 0; i < n; i++)// pItem++)
{
pItem = pList.a[i];
Expr pExpr = pItem.pExpr;
int inReg = sqlite3ExprCodeTarget(pParse, pExpr, target + i);
if (inReg != target + i)
{
sqlite3VdbeAddOp2(pParse.pVdbe, doHardCopy ? OP_Copy : OP_SCopy,
inReg, target + i);
}
}
return n;
}
/*
** Generate code for a BETWEEN operator.
**
** x BETWEEN y AND z
**
** The above is equivalent to
**
** x>=y AND x<=z
**
** Code it as such, taking care to do the common subexpression
** elementation of x.
*/
private static void exprCodeBetween(
Parse pParse, /* Parsing and code generating context */
Expr pExpr, /* The BETWEEN expression */
int dest, /* Jump here if the jump is taken */
int jumpIfTrue, /* Take the jump if the BETWEEN is true */
int jumpIfNull /* Take the jump if the BETWEEN is NULL */
)
{
Expr exprAnd = new Expr(); /* The AND operator in x>=y AND x<=z */
Expr compLeft = new Expr(); /* The x>=y term */
Expr compRight = new Expr(); /* The x<=z term */
Expr exprX; /* The x subexpression */
int regFree1 = 0; /* Temporary use register */
Debug.Assert(!ExprHasProperty(pExpr, EP_xIsSelect));
exprX = pExpr.pLeft.Copy();
exprAnd.op = TK_AND;
exprAnd.pLeft = compLeft;
exprAnd.pRight = compRight;
compLeft.op = TK_GE;
compLeft.pLeft = exprX;
compLeft.pRight = pExpr.x.pList.a[0].pExpr;
compRight.op = TK_LE;
compRight.pLeft = exprX;
compRight.pRight = pExpr.x.pList.a[1].pExpr;
exprX.iTable = sqlite3ExprCodeTemp(pParse, exprX, ref regFree1);
exprX.op = TK_REGISTER;
if (jumpIfTrue != 0)
{
sqlite3ExprIfTrue(pParse, exprAnd, dest, jumpIfNull);
}
else
{
sqlite3ExprIfFalse(pParse, exprAnd, dest, jumpIfNull);
}
sqlite3ReleaseTempReg(pParse, regFree1);
/* Ensure adequate test coverage */
testcase(jumpIfTrue == 0 && jumpIfNull == 0 && regFree1 == 0);
testcase(jumpIfTrue == 0 && jumpIfNull == 0 && regFree1 != 0);
testcase(jumpIfTrue == 0 && jumpIfNull != 0 && regFree1 == 0);
testcase(jumpIfTrue == 0 && jumpIfNull != 0 && regFree1 != 0);
testcase(jumpIfTrue != 0 && jumpIfNull == 0 && regFree1 == 0);
testcase(jumpIfTrue != 0 && jumpIfNull == 0 && regFree1 != 0);
testcase(jumpIfTrue != 0 && jumpIfNull != 0 && regFree1 == 0);
testcase(jumpIfTrue != 0 && jumpIfNull != 0 && regFree1 != 0);
}
/*
** Generate code for a boolean expression such that a jump is made
** to the label "dest" if the expression is true but execution
** continues straight thru if the expression is false.
**
** If the expression evaluates to NULL (neither true nor false), then
** take the jump if the jumpIfNull flag is SQLITE_JUMPIFNULL.
**
** This code depends on the fact that certain token values (ex: TK_EQ)
** are the same as opcode values (ex: OP_Eq) that implement the corresponding
** operation. Special comments in vdbe.c and the mkopcodeh.awk script in
** the make process cause these values to align. Assert()s in the code
** below verify that the numbers are aligned correctly.
*/
private static void sqlite3ExprIfTrue(Parse pParse, Expr pExpr, int dest, int jumpIfNull)
{
Vdbe v = pParse.pVdbe;
int op = 0;
int regFree1 = 0;
int regFree2 = 0;
int r1 = 0, r2 = 0;
Debug.Assert(jumpIfNull == SQLITE_JUMPIFNULL || jumpIfNull == 0);
if (NEVER(v == null))
return; /* Existance of VDBE checked by caller */
if (NEVER(pExpr == null))
return; /* No way this can happen */
op = pExpr.op;
switch (op)
{
case TK_AND:
{
int d2 = sqlite3VdbeMakeLabel(v);
testcase(jumpIfNull == 0);
sqlite3ExprCachePush(pParse);
sqlite3ExprIfFalse(pParse, pExpr.pLeft, d2, jumpIfNull ^ SQLITE_JUMPIFNULL);
sqlite3ExprIfTrue(pParse, pExpr.pRight, dest, jumpIfNull);
sqlite3VdbeResolveLabel(v, d2);
sqlite3ExprCachePop(pParse, 1);
break;
}
case TK_OR:
{
testcase(jumpIfNull == 0);
sqlite3ExprIfTrue(pParse, pExpr.pLeft, dest, jumpIfNull);
sqlite3ExprIfTrue(pParse, pExpr.pRight, dest, jumpIfNull);
break;
}
case TK_NOT:
{
testcase(jumpIfNull == 0);
sqlite3ExprIfFalse(pParse, pExpr.pLeft, dest, jumpIfNull);
break;
}
case TK_LT:
case TK_LE:
case TK_GT:
case TK_GE:
case TK_NE:
case TK_EQ:
{
Debug.Assert(TK_LT == OP_Lt);
Debug.Assert(TK_LE == OP_Le);
Debug.Assert(TK_GT == OP_Gt);
Debug.Assert(TK_GE == OP_Ge);
Debug.Assert(TK_EQ == OP_Eq);
Debug.Assert(TK_NE == OP_Ne);
testcase(op == TK_LT);
testcase(op == TK_LE);
testcase(op == TK_GT);
testcase(op == TK_GE);
testcase(op == TK_EQ);
testcase(op == TK_NE);
testcase(jumpIfNull == 0);
r1 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree1);
r2 = sqlite3ExprCodeTemp(pParse, pExpr.pRight, ref regFree2);
codeCompare(pParse, pExpr.pLeft, pExpr.pRight, op,
r1, r2, dest, jumpIfNull);
testcase(regFree1 == 0);
testcase(regFree2 == 0);
break;
}
case TK_IS:
case TK_ISNOT:
{
testcase(op == TK_IS);
testcase(op == TK_ISNOT);
r1 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree1);
r2 = sqlite3ExprCodeTemp(pParse, pExpr.pRight, ref regFree2);
op = (op == TK_IS) ? TK_EQ : TK_NE;
codeCompare(pParse, pExpr.pLeft, pExpr.pRight, op,
r1, r2, dest, SQLITE_NULLEQ);
testcase(regFree1 == 0);
testcase(regFree2 == 0);
break;
}
case TK_ISNULL:
case TK_NOTNULL:
{
Debug.Assert(TK_ISNULL == OP_IsNull);
Debug.Assert(TK_NOTNULL == OP_NotNull);
testcase(op == TK_ISNULL);
testcase(op == TK_NOTNULL);
r1 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree1);
sqlite3VdbeAddOp2(v, op, r1, dest);
testcase(regFree1 == 0);
break;
}
case TK_BETWEEN:
{
testcase(jumpIfNull == 0);
exprCodeBetween(pParse, pExpr, dest, 1, jumpIfNull);
break;
}
#if SQLITE_OMIT_SUBQUERY
case TK_IN:
{
int destIfFalse = sqlite3VdbeMakeLabel( v );
int destIfNull = jumpIfNull != 0 ? dest : destIfFalse;
sqlite3ExprCodeIN( pParse, pExpr, destIfFalse, destIfNull );
sqlite3VdbeAddOp2( v, OP_Goto, 0, dest );
sqlite3VdbeResolveLabel( v, destIfFalse );
break;
}
#endif
default:
{
r1 = sqlite3ExprCodeTemp(pParse, pExpr, ref regFree1);
sqlite3VdbeAddOp3(v, OP_If, r1, dest, jumpIfNull != 0 ? 1 : 0);
testcase(regFree1 == 0);
testcase(jumpIfNull == 0);
break;
}
}
sqlite3ReleaseTempReg(pParse, regFree1);
sqlite3ReleaseTempReg(pParse, regFree2);
}
/*
** Generate code for a boolean expression such that a jump is made
** to the label "dest" if the expression is false but execution
** continues straight thru if the expression is true.
**
** If the expression evaluates to NULL (neither true nor false) then
** jump if jumpIfNull is SQLITE_JUMPIFNULL or fall through if jumpIfNull
** is 0.
*/
private static void sqlite3ExprIfFalse(Parse pParse, Expr pExpr, int dest, int jumpIfNull)
{
Vdbe v = pParse.pVdbe;
int op = 0;
int regFree1 = 0;
int regFree2 = 0;
int r1 = 0, r2 = 0;
Debug.Assert(jumpIfNull == SQLITE_JUMPIFNULL || jumpIfNull == 0);
if (NEVER(v == null))
return; /* Existance of VDBE checked by caller */
if (pExpr == null)
return;
/* The value of pExpr.op and op are related as follows:
**
** pExpr.op op
** --------- ----------
** TK_ISNULL OP_NotNull
** TK_NOTNULL OP_IsNull
** TK_NE OP_Eq
** TK_EQ OP_Ne
** TK_GT OP_Le
** TK_LE OP_Gt
** TK_GE OP_Lt
** TK_LT OP_Ge
**
** For other values of pExpr.op, op is undefined and unused.
** The value of TK_ and OP_ constants are arranged such that we
** can compute the mapping above using the following expression.
** Assert()s verify that the computation is correct.
*/
op = ((pExpr.op + (TK_ISNULL & 1)) ^ 1) - (TK_ISNULL & 1);
/* Verify correct alignment of TK_ and OP_ constants
*/
Debug.Assert(pExpr.op != TK_ISNULL || op == OP_NotNull);
Debug.Assert(pExpr.op != TK_NOTNULL || op == OP_IsNull);
Debug.Assert(pExpr.op != TK_NE || op == OP_Eq);
Debug.Assert(pExpr.op != TK_EQ || op == OP_Ne);
Debug.Assert(pExpr.op != TK_LT || op == OP_Ge);
Debug.Assert(pExpr.op != TK_LE || op == OP_Gt);
Debug.Assert(pExpr.op != TK_GT || op == OP_Le);
Debug.Assert(pExpr.op != TK_GE || op == OP_Lt);
switch (pExpr.op)
{
case TK_AND:
{
testcase(jumpIfNull == 0);
sqlite3ExprIfFalse(pParse, pExpr.pLeft, dest, jumpIfNull);
sqlite3ExprIfFalse(pParse, pExpr.pRight, dest, jumpIfNull);
break;
}
case TK_OR:
{
int d2 = sqlite3VdbeMakeLabel(v);
testcase(jumpIfNull == 0);
sqlite3ExprCachePush(pParse);
sqlite3ExprIfTrue(pParse, pExpr.pLeft, d2, jumpIfNull ^ SQLITE_JUMPIFNULL);
sqlite3ExprIfFalse(pParse, pExpr.pRight, dest, jumpIfNull);
sqlite3VdbeResolveLabel(v, d2);
sqlite3ExprCachePop(pParse, 1);
break;
}
case TK_NOT:
{
testcase(jumpIfNull == 0);
sqlite3ExprIfTrue(pParse, pExpr.pLeft, dest, jumpIfNull);
break;
}
case TK_LT:
case TK_LE:
case TK_GT:
case TK_GE:
case TK_NE:
case TK_EQ:
{
testcase(op == TK_LT);
testcase(op == TK_LE);
testcase(op == TK_GT);
testcase(op == TK_GE);
testcase(op == TK_EQ);
testcase(op == TK_NE);
testcase(jumpIfNull == 0);
r1 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree1);
r2 = sqlite3ExprCodeTemp(pParse, pExpr.pRight, ref regFree2);
codeCompare(pParse, pExpr.pLeft, pExpr.pRight, op,
r1, r2, dest, jumpIfNull);
testcase(regFree1 == 0);
testcase(regFree2 == 0);
break;
}
case TK_IS:
case TK_ISNOT:
{
testcase(pExpr.op == TK_IS);
testcase(pExpr.op == TK_ISNOT);
r1 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree1);
r2 = sqlite3ExprCodeTemp(pParse, pExpr.pRight, ref regFree2);
op = (pExpr.op == TK_IS) ? TK_NE : TK_EQ;
codeCompare(pParse, pExpr.pLeft, pExpr.pRight, op,
r1, r2, dest, SQLITE_NULLEQ);
testcase(regFree1 == 0);
testcase(regFree2 == 0);
break;
}
case TK_ISNULL:
case TK_NOTNULL:
{
testcase(op == TK_ISNULL);
testcase(op == TK_NOTNULL);
r1 = sqlite3ExprCodeTemp(pParse, pExpr.pLeft, ref regFree1);
sqlite3VdbeAddOp2(v, op, r1, dest);
testcase(regFree1 == 0);
break;
}
case TK_BETWEEN:
{
testcase(jumpIfNull == 0);
exprCodeBetween(pParse, pExpr, dest, 0, jumpIfNull);
break;
}
#if SQLITE_OMIT_SUBQUERY
case TK_IN:
{
if ( jumpIfNull != 0 )
{
sqlite3ExprCodeIN( pParse, pExpr, dest, dest );
}
else
{
int destIfNull = sqlite3VdbeMakeLabel( v );
sqlite3ExprCodeIN( pParse, pExpr, dest, destIfNull );
sqlite3VdbeResolveLabel( v, destIfNull );
}
break;
}
#endif
default:
{
r1 = sqlite3ExprCodeTemp(pParse, pExpr, ref regFree1);
sqlite3VdbeAddOp3(v, OP_IfNot, r1, dest, jumpIfNull != 0 ? 1 : 0);
testcase(regFree1 == 0);
testcase(jumpIfNull == 0);
break;
}
}
sqlite3ReleaseTempReg(pParse, regFree1);
sqlite3ReleaseTempReg(pParse, regFree2);
}
/*
** Do a deep comparison of two expression trees. Return 0 if the two
** expressions are completely identical. Return 1 if they differ only
** by a COLLATE operator at the top level. Return 2 if there are differences
** other than the top-level COLLATE operator.
**
** Sometimes this routine will return 2 even if the two expressions
** really are equivalent. If we cannot prove that the expressions are
** identical, we return 2 just to be safe. So if this routine
** returns 2, then you do not really know for certain if the two
** expressions are the same. But if you get a 0 or 1 return, then you
** can be sure the expressions are the same. In the places where
** this routine is used, it does not hurt to get an extra 2 - that
** just might result in some slightly slower code. But returning
** an incorrect 0 or 1 could lead to a malfunction.
*/
private static int sqlite3ExprCompare(Expr pA, Expr pB)
{
if (pA == null || pB == null)
{
return pB == pA ? 0 : 2;
}
Debug.Assert(!ExprHasAnyProperty(pA, EP_TokenOnly | EP_Reduced));
Debug.Assert(!ExprHasAnyProperty(pB, EP_TokenOnly | EP_Reduced));
if (ExprHasProperty(pA, EP_xIsSelect) || ExprHasProperty(pB, EP_xIsSelect))
{
return 2;
}
if ((pA.flags & EP_Distinct) != (pB.flags & EP_Distinct))
return 2;
if (pA.op != pB.op)
return 2;
if (sqlite3ExprCompare(pA.pLeft, pB.pLeft) != 0)
return 2;
if (sqlite3ExprCompare(pA.pRight, pB.pRight) != 0)
return 2;
if (sqlite3ExprListCompare(pA.x.pList, pB.x.pList) != 0)
return 2;
if (pA.iTable != pB.iTable || pA.iColumn != pB.iColumn)
return 2;
if (ExprHasProperty(pA, EP_IntValue))
{
if (!ExprHasProperty(pB, EP_IntValue) || pA.u.iValue != pB.u.iValue)
{
return 2;
}
}
else if (pA.op != TK_COLUMN && pA.u.zToken != null)
{
if (ExprHasProperty(pB, EP_IntValue) || NEVER(pB.u.zToken == null))
return 2;
if (!pA.u.zToken.Equals(pB.u.zToken, StringComparison.OrdinalIgnoreCase))
{
return 2;
}
}
if ((pA.flags & EP_ExpCollate) != (pB.flags & EP_ExpCollate))
return 1;
if ((pA.flags & EP_ExpCollate) != 0 && pA.pColl != pB.pColl)
return 2;
return 0;
}
/*
** Compare two ExprList objects. Return 0 if they are identical and
** non-zero if they differ in any way.
**
** This routine might return non-zero for equivalent ExprLists. The
** only consequence will be disabled optimizations. But this routine
** must never return 0 if the two ExprList objects are different, or
** a malfunction will result.
**
** Two NULL pointers are considered to be the same. But a NULL pointer
** always differs from a non-NULL pointer.
*/
private static int sqlite3ExprListCompare(ExprList pA, ExprList pB)
{
int i;
if (pA == null && pB == null)
return 0;
if (pA == null || pB == null)
return 1;
if (pA.nExpr != pB.nExpr)
return 1;
for (i = 0; i < pA.nExpr; i++)
{
Expr pExprA = pA.a[i].pExpr;
Expr pExprB = pB.a[i].pExpr;
if (pA.a[i].sortOrder != pB.a[i].sortOrder)
return 1;
if (sqlite3ExprCompare(pExprA, pExprB) != 0)
return 1;
}
return 0;
}
/*
** Add a new element to the pAggInfo.aCol[] array. Return the index of
** the new element. Return a negative number if malloc fails.
*/
private static int addAggInfoColumn(sqlite3 db, AggInfo pInfo)
{
int i = 0;
pInfo.aCol = sqlite3ArrayAllocate(
db,
pInfo.aCol,
-1,//sizeof(pInfo.aCol[0]),
3,
ref pInfo.nColumn,
ref pInfo.nColumnAlloc,
ref i
);
return i;
}
/*
** Add a new element to the pAggInfo.aFunc[] array. Return the index of
** the new element. Return a negative number if malloc fails.
*/
private static int addAggInfoFunc(sqlite3 db, AggInfo pInfo)
{
int i = 0;
pInfo.aFunc = sqlite3ArrayAllocate(
db,
pInfo.aFunc,
-1,//sizeof(pInfo.aFunc[0]),
3,
ref pInfo.nFunc,
ref pInfo.nFuncAlloc,
ref i
);
return i;
}
/*
** This is the xExprCallback for a tree walker. It is used to
** implement sqlite3ExprAnalyzeAggregates(). See sqlite3ExprAnalyzeAggregates
** for additional information.
*/
private static int analyzeAggregate(Walker pWalker, ref Expr pExpr)
{
int i;
NameContext pNC = pWalker.u.pNC;
Parse pParse = pNC.pParse;
SrcList pSrcList = pNC.pSrcList;
AggInfo pAggInfo = pNC.pAggInfo;
switch (pExpr.op)
{
case TK_AGG_COLUMN:
case TK_COLUMN:
{
testcase(pExpr.op == TK_AGG_COLUMN);
testcase(pExpr.op == TK_COLUMN);
/* Check to see if the column is in one of the tables in the FROM
** clause of the aggregate query */
if (ALWAYS(pSrcList != null))
{
SrcList_item pItem;// = pSrcList.a;
for (i = 0; i < pSrcList.nSrc; i++)
{//, pItem++){
pItem = pSrcList.a[i];
AggInfo_col pCol;
Debug.Assert(!ExprHasAnyProperty(pExpr, EP_TokenOnly | EP_Reduced));
if (pExpr.iTable == pItem.iCursor)
{
/* If we reach this point, it means that pExpr refers to a table
** that is in the FROM clause of the aggregate query.
**
** Make an entry for the column in pAggInfo.aCol[] if there
** is not an entry there already.
*/
int k;
//pCol = pAggInfo.aCol;
for (k = 0; k < pAggInfo.nColumn; k++)
{//, pCol++){
pCol = pAggInfo.aCol[k];
if (pCol.iTable == pExpr.iTable &&
pCol.iColumn == pExpr.iColumn)
{
break;
}
}
if ((k >= pAggInfo.nColumn)
&& (k = addAggInfoColumn(pParse.db, pAggInfo)) >= 0
)
{
pCol = pAggInfo.aCol[k];
pCol.pTab = pExpr.pTab;
pCol.iTable = pExpr.iTable;
pCol.iColumn = pExpr.iColumn;
pCol.iMem = ++pParse.nMem;
pCol.iSorterColumn = -1;
pCol.pExpr = pExpr;
if (pAggInfo.pGroupBy != null)
{
int j, n;
ExprList pGB = pAggInfo.pGroupBy;
ExprList_item pTerm;// = pGB.a;
n = pGB.nExpr;
for (j = 0; j < n; j++)
{//, pTerm++){
pTerm = pGB.a[j];
Expr pE = pTerm.pExpr;
if (pE.op == TK_COLUMN && pE.iTable == pExpr.iTable &&
pE.iColumn == pExpr.iColumn)
{
pCol.iSorterColumn = j;
break;
}
}
}
if (pCol.iSorterColumn < 0)
{
pCol.iSorterColumn = pAggInfo.nSortingColumn++;
}
}
/* There is now an entry for pExpr in pAggInfo.aCol[] (either
** because it was there before or because we just created it).
** Convert the pExpr to be a TK_AGG_COLUMN referring to that
** pAggInfo.aCol[] entry.
*/
ExprSetIrreducible(pExpr);
pExpr.pAggInfo = pAggInfo;
pExpr.op = TK_AGG_COLUMN;
pExpr.iAgg = (short)k;
break;
} /* endif pExpr.iTable==pItem.iCursor */
} /* end loop over pSrcList */
}
return WRC_Prune;
}
case TK_AGG_FUNCTION:
{
/* The pNC.nDepth==0 test causes aggregate functions in subqueries
** to be ignored */
if (pNC.nDepth == 0)
{
/* Check to see if pExpr is a duplicate of another aggregate
** function that is already in the pAggInfo structure
*/
AggInfo_func pItem;// = pAggInfo.aFunc;
for (i = 0; i < pAggInfo.nFunc; i++)
{//, pItem++){
pItem = pAggInfo.aFunc[i];
if (sqlite3ExprCompare(pItem.pExpr, pExpr) == 0)
{
break;
}
}
if (i >= pAggInfo.nFunc)
{
/* pExpr is original. Make a new entry in pAggInfo.aFunc[]
*/
u8 enc = pParse.db.aDbStatic[0].pSchema.enc;// ENC(pParse.db);
i = addAggInfoFunc(pParse.db, pAggInfo);
if (i >= 0)
{
Debug.Assert(!ExprHasProperty(pExpr, EP_xIsSelect));
pItem = pAggInfo.aFunc[i];
pItem.pExpr = pExpr;
pItem.iMem = ++pParse.nMem;
Debug.Assert(!ExprHasProperty(pExpr, EP_IntValue));
pItem.pFunc = sqlite3FindFunction(pParse.db,
pExpr.u.zToken, sqlite3Strlen30(pExpr.u.zToken),
pExpr.x.pList != null ? pExpr.x.pList.nExpr : 0, enc, 0);
if ((pExpr.flags & EP_Distinct) != 0)
{
pItem.iDistinct = pParse.nTab++;
}
else
{
pItem.iDistinct = -1;
}
}
}
/* Make pExpr point to the appropriate pAggInfo.aFunc[] entry
*/
Debug.Assert(!ExprHasAnyProperty(pExpr, EP_TokenOnly | EP_Reduced));
ExprSetIrreducible(pExpr);
pExpr.iAgg = (short)i;
pExpr.pAggInfo = pAggInfo;
return WRC_Prune;
}
break;
}
}
return WRC_Continue;
}
private static int analyzeAggregatesInSelect(Walker pWalker, Select pSelect)
{
NameContext pNC = pWalker.u.pNC;
if (pNC.nDepth == 0)
{
pNC.nDepth++;
sqlite3WalkSelect(pWalker, pSelect);
pNC.nDepth--;
return WRC_Prune;
}
else
{
return WRC_Continue;
}
}
/*
** Analyze the given expression looking for aggregate functions and
** for variables that need to be added to the pParse.aAgg[] array.
** Make additional entries to the pParse.aAgg[] array as necessary.
**
** This routine should only be called after the expression has been
** analyzed by sqlite3ResolveExprNames().
*/
private static void sqlite3ExprAnalyzeAggregates(NameContext pNC, ref Expr pExpr)
{
Walker w = new Walker();
w.xExprCallback = (dxExprCallback)analyzeAggregate;
w.xSelectCallback = (dxSelectCallback)analyzeAggregatesInSelect;
w.u.pNC = pNC;
Debug.Assert(pNC.pSrcList != null);
sqlite3WalkExpr(w, ref pExpr);
}
/*
** Call sqlite3ExprAnalyzeAggregates() for every expression in an
** expression list. Return the number of errors.
**
** If an error is found, the analysis is cut short.
*/
private static void sqlite3ExprAnalyzeAggList(NameContext pNC, ExprList pList)
{
ExprList_item pItem;
int i;
if (pList != null)
{
for (i = 0; i < pList.nExpr; i++)//, pItem++)
{
pItem = pList.a[i];
sqlite3ExprAnalyzeAggregates(pNC, ref pItem.pExpr);
}
}
}
/*
** Allocate a single new register for use to hold some intermediate result.
*/
private static int sqlite3GetTempReg(Parse pParse)
{
if (pParse.nTempReg == 0)
{
return ++pParse.nMem;
}
return pParse.aTempReg[--pParse.nTempReg];
}
/*
** Deallocate a register, making available for reuse for some other
** purpose.
**
** If a register is currently being used by the column cache, then
** the dallocation is deferred until the column cache line that uses
** the register becomes stale.
*/
private static void sqlite3ReleaseTempReg(Parse pParse, int iReg)
{
if (iReg != 0 && pParse.nTempReg < ArraySize(pParse.aTempReg))
{
int i;
yColCache p;
for (i = 0; i < SQLITE_N_COLCACHE; i++)//p=pParse.aColCache... p++)
{
p = pParse.aColCache[i];
if (p.iReg == iReg)
{
p.tempReg = 1;
return;
}
}
pParse.aTempReg[pParse.nTempReg++] = iReg;
}
}
/*
** Allocate or deallocate a block of nReg consecutive registers
*/
private static int sqlite3GetTempRange(Parse pParse, int nReg)
{
int i, n;
i = pParse.iRangeReg;
n = pParse.nRangeReg;
if (nReg <= n)
{
//Debug.Assert( 1 == usedAsColumnCache( pParse, i, i + n - 1 ) );
pParse.iRangeReg += nReg;
pParse.nRangeReg -= nReg;
}
else
{
i = pParse.nMem + 1;
pParse.nMem += nReg;
}
return i;
}
private static void sqlite3ReleaseTempRange(Parse pParse, int iReg, int nReg)
{
sqlite3ExprCacheRemove(pParse, iReg, nReg);
if (nReg > pParse.nRangeReg)
{
pParse.nRangeReg = nReg;
pParse.iRangeReg = iReg;
}
}
}
}