[llvm] [AMDGPU] Always Inline preserved analyses (PR #91198)

[via llvm-commits]

https://github.com/jofrn updated https://github.com/llvm/llvm-project/pull/91198

>From 8841b046c81ffb3ccc9c22f1e2cddfac864a070a Mon Sep 17 00:00:00 2001
From: Joe Fernau <joe.fernau at amd.com>
Date: Mon, 6 May 2024 10:13:47 -0400
Subject: [PATCH] [AMDGPU] Always Inline preserved analyses

When replacing all uses, the structural-hash of the IR can change, so keep track of changes using Changed variable and return it to pass manager.
---
 llvm/lib/Target/AMDGPU/AMDGPUAlwaysInlinePass.cpp | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/llvm/lib/Target/AMDGPU/AMDGPUAlwaysInlinePass.cpp b/llvm/lib/Target/AMDGPU/AMDGPUAlwaysInlinePass.cpp
index b53def912ab618..f55f656ff922c1 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUAlwaysInlinePass.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUAlwaysInlinePass.cpp
@@ -42,7 +42,7 @@ class AMDGPUAlwaysInline : public ModulePass {
 
   void getAnalysisUsage(AnalysisUsage &AU) const override {
     AU.setPreservesAll();
- }
+  }
 };
 
 } // End anonymous namespace
@@ -89,6 +89,7 @@ recursivelyVisitUsers(GlobalValue &GV,
 static bool alwaysInlineImpl(Module &M, bool GlobalOpt) {
   std::vector<GlobalAlias*> AliasesToRemove;
 
+  bool Changed = false;
   SmallPtrSet<Function *, 8> FuncsToAlwaysInline;
   SmallPtrSet<Function *, 8> FuncsToNoInline;
   Triple TT(M.getTargetTriple());
@@ -98,6 +99,7 @@ static bool alwaysInlineImpl(Module &M, bool GlobalOpt) {
       if (TT.getArch() == Triple::amdgcn &&
           A.getLinkage() != GlobalValue::InternalLinkage)
         continue;
+      Changed = true;
       A.replaceAllUsesWith(F);
       AliasesToRemove.push_back(&A);
     }
@@ -153,7 +155,7 @@ static bool alwaysInlineImpl(Module &M, bool GlobalOpt) {
   for (Function *F : FuncsToNoInline)
     F->addFnAttr(Attribute::NoInline);
 
-  return !FuncsToAlwaysInline.empty() || !FuncsToNoInline.empty();
+  return Changed || !FuncsToAlwaysInline.empty() || !FuncsToNoInline.empty();
 }
 
 bool AMDGPUAlwaysInline::runOnModule(Module &M) {
@@ -166,6 +168,6 @@ ModulePass *llvm::createAMDGPUAlwaysInlinePass(bool GlobalOpt) {
 
 PreservedAnalyses AMDGPUAlwaysInlinePass::run(Module &M,
                                               ModuleAnalysisManager &AM) {
-  alwaysInlineImpl(M, GlobalOpt);
-  return PreservedAnalyses::all();
+  const bool Changed = alwaysInlineImpl(M, GlobalOpt);
+  return Changed ? PreservedAnalyses::none() : PreservedAnalyses::all();
 }