Stop iterating through all of runtimeFunction.DebugInfo.BoundsList for each instruction

ILSpy.ReadyToRun/ReadyToRunDisassembler.cs

@@ -105,27 +105,32 @@ namespace ICSharpCode.ILSpy.ReadyToRun
 			formatter.Options.FirstOperandCharIndex = 10;
 			var tempOutput = new StringOutput();
 			ulong baseInstrIP = instructions[0].IP;
+
+			var boundsMap = new Dictionary<uint, uint>();
+			foreach (var bound in runtimeFunction.DebugInfo.BoundsList)
+			{
+				// ignoring the return value assuming the same key is always mapped to the same value in runtimeFunction.DebugInfo.BoundsList
+				boundsMap.TryAdd(bound.NativeOffset, bound.ILOffset);
+			}
+
 			foreach (var instr in instructions)
 			{
 				int byteBaseIndex = (int)(instr.IP - address);
 				if (isShowDebugInfo && runtimeFunction.DebugInfo != null)
 				{
-					foreach (var bound in runtimeFunction.DebugInfo.BoundsList)
+					if (byteBaseIndex >= 0 && boundsMap.TryGetValue((uint)byteBaseIndex, out uint boundILOffset))
-					{
-						if (bound.NativeOffset == byteBaseIndex)
 					{
-							if (bound.ILOffset == (uint)DebugInfoBoundsType.Prolog)
+						if (boundILOffset == (uint)DebugInfoBoundsType.Prolog)
 						{
 							WriteCommentLine("Prolog");
 						}
-							else if (bound.ILOffset == (uint)DebugInfoBoundsType.Epilog)
+						else if (boundILOffset == (uint)DebugInfoBoundsType.Epilog)
 						{
 							WriteCommentLine("Epilog");
 						}
 						else
 						{
-								WriteCommentLine($"IL_{bound.ILOffset:x4}");
+							WriteCommentLine($"IL_{boundILOffset:x4}");
-							}
 						}
 					}
 				}