Replace a static readonly in[] in System.Data.Common (#72743)

There are a small number of values, all within the byte range.

diff --git a/src/libraries/System.Data.Common/src/System/Data/Filter/ExpressionParser.cs b/src/libraries/System.Data.Common/src/System/Data/Filter/ExpressionParser.cs
index b9adf16..98901f3 100644 (file)
--- a/src/libraries/System.Data.Common/src/System/Data/Filter/ExpressionParser.cs
+++ b/src/libraries/System.Data.Common/src/System/Data/Filter/ExpressionParser.cs
@@ -152,7 +152,7 @@ namespace System.Data
             _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
@@ -192,7 +192,7 @@ namespace System.Data
                             throw ExprException.MissingOperand(opInfo);
                         }
                         // collect all nodes
-                        BuildExpression(Operators.priLow);
+                        BuildExpression(Operators.PriLow);
                         if (_topOperator != 1)
                         {
                             throw ExprException.MissingRightParen();
@@ -329,12 +329,12 @@ namespace System.Data
                                 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
@@ -342,7 +342,7 @@ namespace System.Data
                             // 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();
 
@@ -371,7 +371,7 @@ namespace System.Data
                             }
 
                             NodePush(node);
-                            _ops[_topOperator++] = new OperatorInfo(Nodes.Call, Operators.Noop, Operators.priParen);
+                            _ops[_topOperator++] = new OperatorInfo(Nodes.Call, Operators.Noop, Operators.PriParen);
                         }
                         goto loop;
 
@@ -380,7 +380,7 @@ namespace System.Data
                             /* 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. */
@@ -400,7 +400,7 @@ namespace System.Data
                                 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)
                             {
@@ -445,7 +445,7 @@ namespace System.Data
                             /* We are be in a procedure call */
 
                             /* build next argument */
-                            BuildExpression(Operators.priLow);
+                            BuildExpression(Operators.PriLow);
 
                             opInfo = _ops[_topOperator - 1];
 
@@ -518,7 +518,7 @@ namespace System.Data
                         }
 
                         // PushOperator descriptor
-                        _ops[_topOperator++] = new OperatorInfo(Nodes.Zop, _op, Operators.priMax);
+                        _ops[_topOperator++] = new OperatorInfo(Nodes.Zop, _op, Operators.PriMax);
                         _prevOperand = Expr;
                         goto loop;
 
@@ -655,7 +655,7 @@ namespace System.Data
         {
             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) */

diff --git a/src/libraries/System.Data.Common/src/System/Data/Filter/Operators.cs b/src/libraries/System.Data.Common/src/System/Data/Filter/Operators.cs
index 75e35ce..f48dea6 100644 (file)
--- a/src/libraries/System.Data.Common/src/System/Data/Filter/Operators.cs
+++ b/src/libraries/System.Data.Common/src/System/Data/Filter/Operators.cs
@@ -89,64 +89,57 @@ namespace System.Data
         /// <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>