[llvm] [X86] Remove outdated comment (PR #133743)

[Mikołaj Piróg via llvm-commits]

https://github.com/mikolaj-pirog created https://github.com/llvm/llvm-project/pull/133743

A part of the comment is out of date -- the Intel SDM doesn't have a chapter (nor any string) named that way. We could update it, but I believe it's better to simply remove it -- it's hard to maintain, and I feel it's unnecessary.

>From 84c5d64ab96e6c13ae3b444e4028db3983dc6c52 Mon Sep 17 00:00:00 2001
From: "Pirog, Mikolaj Maciej" <mikolaj.maciej.pirog at intel.com>
Date: Mon, 31 Mar 2025 18:04:02 +0200
Subject: [PATCH] Remove wrong comment

---
 llvm/lib/Target/X86/X86.td | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/llvm/lib/Target/X86/X86.td b/llvm/lib/Target/X86/X86.td
index 38761e1fd7eec..7421abf1968b9 100644
--- a/llvm/lib/Target/X86/X86.td
+++ b/llvm/lib/Target/X86/X86.td
@@ -371,8 +371,7 @@ def FeatureMOVRS   : SubtargetFeature<"movrs", "HasMOVRS", "true",
                            "Enable MOVRS", []>;
 
 // Ivy Bridge and newer processors have enhanced REP MOVSB and STOSB (aka
-// "string operations"). See "REP String Enhancement" in the Intel Software
-// Development Manual. This feature essentially means that REP MOVSB will copy
+// "string operations"). This feature essentially means that REP MOVSB will copy
 // using the largest available size instead of copying bytes one by one, making
 // it at least as fast as REPMOVS{W,D,Q}.
 def FeatureERMSB