Make the pre-increment operators work on static fields.

ICSharpCode.Decompiler/Ast/Transforms/ReplaceMethodCallsWithOperators.cs

@@ -235,9 +235,7 @@ namespace ICSharpCode.Decompiler.Ast.Transforms
 		
 		static bool IsWithoutSideEffects(Expression left)
 		{
-			if (left is ThisReferenceExpression)
-				return true;
-			if (left is IdentifierExpression)
+			if (left is ThisReferenceExpression || left is IdentifierExpression || left is TypeReferenceExpression)
 				return true;
 			MemberReferenceExpression mre = left as MemberReferenceExpression;
 			if (mre != null)

ICSharpCode.Decompiler/ILAst/PatternMatching.cs

@@ -28,16 +28,6 @@ namespace ICSharpCode.Decompiler.ILAst
 			return false;
 		}
 		
-		public static bool Match<T>(this ILNode node, ILCode code, T operand)
-		{
-			ILExpression expr = node as ILExpression;
-			if (expr != null && expr.Prefixes == null && expr.Code == code) {
-				Debug.Assert(expr.Arguments.Count == 0);
-				return operand.Equals(expr.Operand);
-			}
-			return false;
-		}
-		
 		public static bool Match(this ILNode node, ILCode code, out List<ILExpression> args)
 		{
 			ILExpression expr = node as ILExpression;

ICSharpCode.Decompiler/ILAst/PeepholeTransform.cs

@@ -190,16 +190,14 @@ namespace ICSharpCode.Decompiler.ILAst
 			// stloc(v, exprVar)
 			// ->
 			// exprVar = stloc(v, ...))
-			ILExpression nextExpr = body.ElementAtOrDefault(pos + 1) as ILExpression;
 			ILVariable exprVar;
 			ILExpression initializer;
+			if (!(expr.Match(ILCode.Stloc, out exprVar, out initializer) && exprVar.IsGenerated))
+				return false;
+			ILExpression nextExpr = body.ElementAtOrDefault(pos + 1) as ILExpression;
 			ILVariable v;
 			ILExpression stLocArg;
-			if (expr.Match(ILCode.Stloc, out exprVar, out initializer) &&
-			    exprVar.IsGenerated &&
-			    nextExpr.Match(ILCode.Stloc, out v, out stLocArg) &&
-			    stLocArg.Match(ILCode.Ldloc, exprVar))
-			{
+			if (nextExpr.Match(ILCode.Stloc, out v, out stLocArg) && stLocArg.MatchLdloc(exprVar)) {
 				ILExpression store2 = body.ElementAtOrDefault(pos + 2) as ILExpression;
 				if (StoreCanBeConvertedToAssignment(store2, exprVar)) {
 					// expr_44 = ...
@@ -224,6 +222,18 @@ namespace ICSharpCode.Decompiler.ILAst
 				nextExpr.Arguments[0] = initializer;
 				((ILExpression)body[pos]).Arguments[0] = nextExpr;
 				return true;
+			} else {
+				// exprVar = ...
+				// stsfld(fld, exprVar)
+				// ->
+				// exprVar = stsfld(fld, ...))
+				FieldReference field;
+				if (nextExpr.Match(ILCode.Stsfld, out field, out stLocArg) && stLocArg.MatchLdloc(exprVar)) {
+					body.RemoveAt(pos + 1); // remove stfld
+					nextExpr.Arguments[0] = initializer;
+					((ILExpression)body[pos]).Arguments[0] = nextExpr;
+					return true;
+				}
 			}
 			return false;
 		}

ICSharpCode.Decompiler/ILAst/SimpleControlFlow.cs

@@ -152,7 +152,7 @@ namespace ICSharpCode.Decompiler.ILAst
 				head.Body[head.Body.Count - 3].Match(ILCode.Stloc, out v, out leftExpr) &&
 			    leftExpr.Match(ILCode.Ldloc, out leftVar) &&
 			    head.MatchLastAndBr(ILCode.Brtrue, out endBBLabel, out leftExpr2, out rightBBLabel) &&
-			    leftExpr2.Match(ILCode.Ldloc, leftVar) &&
+			    leftExpr2.MatchLdloc(leftVar) &&
 			    labelToBasicBlock.TryGetValue(rightBBLabel, out rightBB) &&
 			    rightBB.MatchSingleAndBr(ILCode.Stloc, out v2, out rightExpr, out endBBLabel2) &&
 			    v == v2 &&

ICSharpCode.Decompiler/Tests/IncrementDecrement.cs

@@ -10,6 +10,8 @@ public class IncrementDecrement
 		public int Field;
 	}
 	
+	public static int StaticField;
+	
 	private IncrementDecrement.MutableClass M()
 	{
 		return new IncrementDecrement.MutableClass();
@@ -35,11 +37,21 @@ public class IncrementDecrement
 		return ++m.Field;
 	}
 	
+	public int PreIncrementStaticField()
+	{
+		return ++IncrementDecrement.StaticField;
+	}
+	
 	public int CompoundMultiplyInstanceField()
 	{
 		return this.M().Field *= 10;
 	}
 	
+	public int CompoundXorStaticField()
+	{
+		return IncrementDecrement.StaticField ^= 100;
+	}
+	
 	public int CompoundMultiplyArrayElement1(int[] array, int pos)
 	{
 		return array[pos] *= 10;