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Replace a static readonly in[] in System.Data.Common (#72743)
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There are a small number of values, all within the byte range.
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@stephentoub
stephentoub authored Jul 24, 2022
1 parent b5fd812 commit 9f68db2
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Showing 2 changed files with 57 additions and 64 deletions.
22 changes: 11 additions & 11 deletions src/libraries/System.Data.Common/src/System/Data/Filter/ExpressionParser.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -152,7 +152,7 @@ internal void StartScan()
_start = 0;

_topOperator = 0;
_ops[_topOperator++] = new OperatorInfo(Nodes.Noop, Operators.Noop, Operators.priStart);
_ops[_topOperator++] = new OperatorInfo(Nodes.Noop, Operators.Noop, Operators.PriStart);
}

// CONSIDER: configure the scanner : local info
Expand Down Expand Up @@ -192,7 +192,7 @@ internal ExpressionNode Parse()
throw ExprException.MissingOperand(opInfo);
}
// collect all nodes
BuildExpression(Operators.priLow);
BuildExpression(Operators.PriLow);
if (_topOperator != 1)
{
throw ExprException.MissingRightParen();
Expand Down Expand Up @@ -329,20 +329,20 @@ internal ExpressionNode Parse()
node = new FunctionNode(_table, "In");
NodePush(node);
/* Push operator decriptor */
_ops[_topOperator++] = new OperatorInfo(Nodes.Call, Operators.Noop, Operators.priParen);
_ops[_topOperator++] = new OperatorInfo(Nodes.Call, Operators.Noop, Operators.PriParen);
}
else
{ /* Normal ( */
/* Push operator decriptor */
_ops[_topOperator++] = new OperatorInfo(Nodes.Paren, Operators.Noop, Operators.priParen);
_ops[_topOperator++] = new OperatorInfo(Nodes.Paren, Operators.Noop, Operators.PriParen);
}
}
else
{
// This is a procedure call or () qualification
// Force out any dot qualifiers; check for bomb

BuildExpression(Operators.priProc);
BuildExpression(Operators.PriProc);
_prevOperand = Empty;
ExpressionNode? nodebefore = NodePeek();

Expand Down Expand Up @@ -371,7 +371,7 @@ internal ExpressionNode Parse()
}

NodePush(node);
_ops[_topOperator++] = new OperatorInfo(Nodes.Call, Operators.Noop, Operators.priParen);
_ops[_topOperator++] = new OperatorInfo(Nodes.Call, Operators.Noop, Operators.PriParen);
}
goto loop;

Expand All @@ -380,7 +380,7 @@ internal ExpressionNode Parse()
/* Right parentheses: Build expression if we have an operand. */
if (_prevOperand != Empty)
{
BuildExpression(Operators.priLow);
BuildExpression(Operators.PriLow);
}

/* We must have Tokens.LeftParen on stack. If no operand, must be procedure call. */
Expand All @@ -400,7 +400,7 @@ internal ExpressionNode Parse()
throw ExprException.MissingOperand(opInfo);
}

Debug.Assert(opInfo._priority == Operators.priParen, "melformed operator stack.");
Debug.Assert(opInfo._priority == Operators.PriParen, "melformed operator stack.");

if (opInfo._type == Nodes.Call)
{
Expand Down Expand Up @@ -445,7 +445,7 @@ internal ExpressionNode Parse()
/* We are be in a procedure call */

/* build next argument */
BuildExpression(Operators.priLow);
BuildExpression(Operators.PriLow);

opInfo = _ops[_topOperator - 1];

Expand Down Expand Up @@ -518,7 +518,7 @@ internal ExpressionNode Parse()
}

// PushOperator descriptor
_ops[_topOperator++] = new OperatorInfo(Nodes.Zop, _op, Operators.priMax);
_ops[_topOperator++] = new OperatorInfo(Nodes.Zop, _op, Operators.PriMax);
_prevOperand = Expr;
goto loop;

Expand Down Expand Up @@ -655,7 +655,7 @@ private void BuildExpression(int pri)
{
ExpressionNode? expr;

Debug.Assert(pri > Operators.priStart && pri <= Operators.priMax, "Invalid priority value");
Debug.Assert(pri > Operators.PriStart && pri <= Operators.PriMax, "Invalid priority value");

/* For all operators of higher or same precedence (we are always
left-associative) */
Expand Down
99 changes: 46 additions & 53 deletions src/libraries/System.Data.Common/src/System/Data/Filter/Operators.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -89,64 +89,57 @@ internal static bool IsRelational(int op)
/// <summary>
/// Operator priorities
/// </summary>
internal const int priStart = 0;
internal const int priSubstr = 1;
internal const int priParen = 2;
internal const int priLow = 3;
internal const int priImp = 4;
internal const int priEqv = 5;
internal const int priXor = 6;
internal const int priOr = 7;
internal const int priAnd = 8;
internal const int priNot = 9;
internal const int priIs = 10;
internal const int priBetweenInLike = 11;
internal const int priBetweenAnd = 12;
internal const int priRelOp = 13;
internal const int priConcat = 14;
internal const int priContains = 15;
internal const int priPlusMinus = 16;
internal const int priMod = 17;
internal const int priIDiv = 18;
internal const int priMulDiv = 19;
internal const int priNeg = 20;
internal const int priExp = 21;
internal const int priProc = 22;
internal const int priDot = 23;
internal const int priMax = 24;

/// <summary>
/// Mapping from Operator to priorities
/// CONSIDER: fast, but hard to maintain
/// </summary>

private static readonly int[] s_priority = new int[] {
priStart, // Noop
priNeg, priNeg, priNot, // Unary -, +, Not
priBetweenAnd, priBetweenInLike, priBetweenInLike,
priRelOp, priRelOp, priRelOp, priRelOp, priRelOp, priRelOp,
priIs,
priBetweenInLike, // Like
internal const byte PriStart = 0;
internal const byte PriSubstr = 1;
internal const byte PriParen = 2;
internal const byte PriLow = 3;
internal const byte PriImp = 4;
internal const byte PriEqv = 5;
internal const byte PriXor = 6;
internal const byte PriOr = 7;
internal const byte PriAnd = 8;
internal const byte PriNot = 9;
internal const byte PriIs = 10;
internal const byte PriBetweenInLike = 11;
internal const byte PriBetweenAnd = 12;
internal const byte PriRelOp = 13;
internal const byte PriConcat = 14;
internal const byte PriContains = 15;
internal const byte PriPlusMinus = 16;
internal const byte PriMod = 17;
internal const byte PriIDiv = 18;
internal const byte PriMulDiv = 19;
internal const byte PriNeg = 20;
internal const byte PriExp = 21;
internal const byte PriProc = 22;
internal const byte PriDot = 23;
internal const byte PriMax = 24;

/// <summary>Mapping from Operator to priorities.</summary>
internal static int Priority(int op)
{
ReadOnlySpan<byte> priorities = new byte[]
{
PriStart, // Noop
PriNeg, PriNeg, PriNot, // Unary -, +, Not
PriBetweenAnd, PriBetweenInLike, PriBetweenInLike,
PriRelOp, PriRelOp, PriRelOp, PriRelOp, PriRelOp, PriRelOp,
PriIs,
PriBetweenInLike, // Like

priPlusMinus, priPlusMinus, // +, -
priMulDiv, priMulDiv, priIDiv, priMod, // *, /, \, Mod
priExp, // **
PriPlusMinus, PriPlusMinus, // +, -
PriMulDiv, PriMulDiv, PriIDiv, PriMod, // *, /, \, Mod
PriExp, // **

priAnd, priOr, priXor, priNot,
priAnd, priOr,
PriAnd, PriOr, PriXor, PriNot,
PriAnd, PriOr,

priParen, priProc, priDot, priDot, // Proc, Iff, Qula, Dot..
PriParen, PriProc, PriDot, PriDot, // Proc, Iff, Qula, Dot..

priMax, priMax, priMax, priMax, priMax, priMax, priMax,
priMax, priMax, priMax, priMax,
priMax,
};
// anything beyond is PriMax
};

internal static int Priority(int op)
{
if ((uint)op >= (uint)s_priority.Length)
return priMax;
return s_priority[op];
return (uint)op < (uint)priorities.Length ? priorities[op] : PriMax;
}

/// <summary>
Expand Down

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