From 43849ad79000a5317f1a6aa1d36225f5b4ba44a8 Mon Sep 17 00:00:00 2001
From: ncave <test2@hotmail.com>
Date: Mon, 20 Nov 2017 09:11:14 -0800
Subject: [PATCH] List.fold IL simplification

---
 src/fsharp/FSharp.Core/list.fs | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/fsharp/FSharp.Core/list.fs b/src/fsharp/FSharp.Core/list.fs
index 6b31ea2b0f..45eccc3f3a 100644
--- a/src/fsharp/FSharp.Core/list.fs
+++ b/src/fsharp/FSharp.Core/list.fs
@@ -216,11 +216,10 @@ namespace Microsoft.FSharp.Collections
             | [] -> state
             | _ -> 
                 let f = OptimizedClosures.FSharpFunc<_,_,_>.Adapt(folder)
-                let rec loop s xs = 
-                    match xs with 
-                    | [] -> s
-                    | h::t -> loop (f.Invoke(s,h)) t
-                loop state list
+                let mutable acc = state
+                for x in list do
+                    acc <- f.Invoke(acc, x)
+                acc
 
         [<CompiledName("Pairwise")>]
         let pairwise (list: 'T list) =