[llvm] [WebAssembly] Port WebAssemblyOptimizeReturnedPass (PR #209036)

[Heejin Ahn via llvm-commits]

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@@ -70,12 +79,27 @@ void OptimizeReturned::visitCallBase(CallBase &CB) {
     }
 }
 
-bool OptimizeReturned::runOnFunction(Function &F) {
+bool WebAssemblyOptimizeReturnedImpl::runOnFunction(Function &F) {
   LLVM_DEBUG(dbgs() << "********** Optimize returned Attributes **********\n"
                        "********** Function: "
                     << F.getName() << '\n');
 
-  DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
   visit(F);
   return true;
 }
+
+bool WebAssemblyOptimizeReturnedLegacy::runOnFunction(Function &F) {
+  DominatorTree *DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
+  WebAssemblyOptimizeReturnedImpl Impl(DT);
+  return Impl.runOnFunction(F);
+}
+
+PreservedAnalyses
+WebAssemblyOptimizeReturnedPass::run(Function &F,
+                                     FunctionAnalysisManager &FAM) {
+  DominatorTree *DT = &FAM.getResult<DominatorTreeAnalysis>(F);
+  WebAssemblyOptimizeReturnedImpl Impl(DT);
+  return Impl.runOnFunction(F)
+             ? PreservedAnalyses::none().preserveSet<CFGAnalyses>()
+             : PreservedAnalyses::all();
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aheejin wrote:

https://github.com/llvm/llvm-project/blob/6a33b69d8bae737e5e1d60c7b7776a0b1f885bfa/llvm/lib/Target/WebAssembly/WebAssemblyOptimizeReturned.cpp#L41-L46

We seem to preserve `DominatorTree` too

https://github.com/llvm/llvm-project/pull/209036