[llvm] CodeGen: Make TargetInstrInfo constructor protected (PR #157336)

[Matt Arsenault via llvm-commits]

https://github.com/arsenm created https://github.com/llvm/llvm-project/pull/157336

There's no use for the standalone base class TargetRegisterInfo
and TargetSubtargetInfo already do this.

>From df3ba086fe4db1d3353f146143476973e9244b0d Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault at amd.com>
Date: Sun, 7 Sep 2025 18:32:37 +0900
Subject: [PATCH] CodeGen: Make TargetInstrInfo constructor protected

There's no use for the standalone base class TargetRegisterInfo
and TargetSubtargetInfo already do this.
---
 llvm/include/llvm/CodeGen/TargetInstrInfo.h | 4 +++-
 llvm/unittests/CodeGen/MFCommon.inc         | 7 ++++++-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/llvm/include/llvm/CodeGen/TargetInstrInfo.h b/llvm/include/llvm/CodeGen/TargetInstrInfo.h
index b5b83c7ff1164..087affcfd55ce 100644
--- a/llvm/include/llvm/CodeGen/TargetInstrInfo.h
+++ b/llvm/include/llvm/CodeGen/TargetInstrInfo.h
@@ -112,12 +112,14 @@ struct ExtAddrMode {
 /// TargetInstrInfo - Interface to description of machine instruction set
 ///
 class LLVM_ABI TargetInstrInfo : public MCInstrInfo {
-public:
+protected:
   TargetInstrInfo(unsigned CFSetupOpcode = ~0u, unsigned CFDestroyOpcode = ~0u,
                   unsigned CatchRetOpcode = ~0u, unsigned ReturnOpcode = ~0u)
       : CallFrameSetupOpcode(CFSetupOpcode),
         CallFrameDestroyOpcode(CFDestroyOpcode), CatchRetOpcode(CatchRetOpcode),
         ReturnOpcode(ReturnOpcode) {}
+
+public:
   TargetInstrInfo(const TargetInstrInfo &) = delete;
   TargetInstrInfo &operator=(const TargetInstrInfo &) = delete;
   virtual ~TargetInstrInfo();
diff --git a/llvm/unittests/CodeGen/MFCommon.inc b/llvm/unittests/CodeGen/MFCommon.inc
index 425453fb0e280..cb4a2410df08b 100644
--- a/llvm/unittests/CodeGen/MFCommon.inc
+++ b/llvm/unittests/CodeGen/MFCommon.inc
@@ -75,6 +75,11 @@ public:
   }
 };
 
+class BogusTargetInstrInfo : public TargetInstrInfo {
+public:
+  BogusTargetInstrInfo() : TargetInstrInfo() {}
+};
+
 class BogusSubtarget : public TargetSubtargetInfo {
 public:
   BogusSubtarget(TargetMachine &TM)
@@ -95,7 +100,7 @@ private:
   BogusFrameLowering FL;
   BogusRegisterInfo TRI;
   BogusTargetLowering TL;
-  TargetInstrInfo TII;
+  BogusTargetInstrInfo TII;
 };
 
 static TargetOptions getTargetOptionsForBogusMachine() {