From d43aec85ca4d5565c69f39fab204ba8d7436239f Mon Sep 17 00:00:00 2001
From: Rolf Bjarne Kvinge <rolf@xamarin.com>
Date: Mon, 27 May 2024 13:44:28 +0200
Subject: [PATCH] [tools] Update how we encode AOT symbols according to
 upstream changes.

Ref: https://github.com/dotnet/runtime/pull/101681.
---
 tools/common/Target.cs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/tools/common/Target.cs b/tools/common/Target.cs
index 3afd261f0a76..3e674c7b802a 100644
--- a/tools/common/Target.cs
+++ b/tools/common/Target.cs
@@ -933,10 +933,13 @@ void GenerateIOSMain (StringWriter sw, Abi abi)
 			sw.WriteLine ("}");
 		}
 
+		static readonly char[] charsToReplaceAot = new[] { '.', '-', '+', '<', '>' };
 		static string EncodeAotSymbol (string symbol)
 		{
 			var sb = new StringBuilder ();
 			/* This mimics what the aot-compiler does */
+			// https://github.com/dotnet/runtime/blob/2f08fcbfece0c09319f237a6aee6f74c4a9e14e8/src/mono/mono/metadata/native-library.c#L1265-L1284
+			// https://github.com/dotnet/runtime/blob/2f08fcbfece0c09319f237a6aee6f74c4a9e14e8/src/tasks/Common/Utils.cs#L419-L445
 			foreach (var b in System.Text.Encoding.UTF8.GetBytes (symbol)) {
 				char c = (char) b;
 				if ((c >= '0' && c <= '9') ||
@@ -944,8 +947,12 @@ static string EncodeAotSymbol (string symbol)
 					(c >= 'A' && c <= 'Z')) {
 					sb.Append (c);
 					continue;
+				} else if (charsToReplaceAot.Contains (c)) {
+					sb.Append ('_');
+				} else {
+					// Append the hex representation of b between underscores
+					sb.Append ($"_{b:X}_");
 				}
-				sb.Append ('_');
 			}
 			return sb.ToString ();
 		}