Fixed type analysis for right shift operator.

ICSharpCode.Decompiler/ILAst/TypeAnalysis.cs

@@ -526,9 +526,36 @@ namespace ICSharpCode.Decompiler.ILAst
 						return NumericPromotion(InferTypeForExpression(expr.Arguments[0], null));
 				case ILCode.Shr:
 				case ILCode.Shr_Un:
-					if (forceInferChildren)
-						InferTypeForExpression(expr.Arguments[1], typeSystem.Int32);
-					return NumericPromotion(InferTypeForExpression(expr.Arguments[0], null));
+					{
+						if (forceInferChildren)
+							InferTypeForExpression(expr.Arguments[1], typeSystem.Int32);
+						TypeReference type = NumericPromotion(InferTypeForExpression(expr.Arguments[0], null));
+						TypeReference expectedInputType = null;
+						switch (type.MetadataType) {
+							case MetadataType.Int32:
+								if (expr.Code == ILCode.Shr_Un)
+									expectedInputType = typeSystem.UInt32;
+								break;
+							case MetadataType.UInt32:
+								if (expr.Code == ILCode.Shr)
+									expectedInputType = typeSystem.Int32;
+								break;
+							case MetadataType.Int64:
+								if (expr.Code == ILCode.Shr_Un)
+									expectedInputType = typeSystem.UInt64;
+								break;
+							case MetadataType.UInt64:
+								if (expr.Code == ILCode.Shr)
+									expectedInputType = typeSystem.UInt64;
+								break;
+						}
+						if (expectedInputType != null) {
+							InferTypeForExpression(expr.Arguments[0], expectedInputType);
+							return expectedInputType;
+						} else {
+							return type;
+						}
+					}
 				case ILCode.CompoundAssignment:
 					{
 						TypeReference varType = InferTypeForExpression(expr.Arguments[0].Arguments[0], null);
@@ -1097,7 +1124,6 @@ namespace ICSharpCode.Decompiler.ILAst
 					return char.MinValue <= num && num <= char.MaxValue;
 				case MetadataType.UInt16:
 					return ushort.MinValue <= num && num <= ushort.MaxValue;
-					break;
 				default:
 					return true;
 			}

ICSharpCode.Decompiler/Tests/TypeAnalysisTests.cs

@@ -25,9 +25,45 @@ public class TypeAnalysisTests
 		return (byte)(256 - (int)b);
 	}
 	
-	public int GetHashCode(long num)
+	#region Shift
+	public int LShiftInteger(int num1, int num2)
 	{
-		return (int)num ^ (int)(num >> 32);
+		return num1 << num2;
+	}
+	
+	public uint LShiftUnsignedInteger(uint num1, uint num2)
+	{
+		return num1 << (int)num2;
+	}
+	
+	public long LShiftLong(long num1, long num2)
+	{
+		return num1 << (int)num2;
+	}
+	
+	public ulong LShiftUnsignedLong(ulong num1, ulong num2)
+	{
+		return num1 << (int)num2;
+	}
+	
+	public int RShiftInteger(int num1, int num2)
+	{
+		return num1 >> num2;
+	}
+	
+	public uint RShiftUnsignedInteger(uint num1, int num2)
+	{
+		return num1 >> num2;
+	}
+	
+	public long RShiftLong(long num1, long num2)
+	{
+		return num1 >> (int)num2;
+	}
+	
+	public ulong RShiftUnsignedLong(ulong num1, ulong num2)
+	{
+		return num1 >> (int)num2;
 	}
 	
 	public int ShiftByte(byte num)
@@ -40,7 +76,12 @@ public class TypeAnalysisTests
 		return num >> 8;
 	}
 	
-	public int RShiftByteWithSignExtension(byte num)
+	public uint RShiftByteWithZeroExtension(byte num)
+	{
+		return (uint)num >> 8;
+	}
+	
+	public int RShiftByteAsSByte(byte num)
 	{
 		return (sbyte)num >> 8;
 	}
@@ -50,8 +91,19 @@ public class TypeAnalysisTests
 		return num >> 8;
 	}
 	
-	public int RShiftSByteWithZeroExtension(sbyte num)
+	public uint RShiftSByteWithZeroExtension(sbyte num)
+	{
+		return (uint)num >> 8;
+	}
+	
+	public int RShiftSByteAsByte(sbyte num)
 	{
 		return (byte)num >> 8;
 	}
+	#endregion
+	
+	public int GetHashCode(long num)
+	{
+		return (int)num ^ (int)(num >> 32);
+	}
 }