[llvm] [CodeGen][NPM] Port UnreachableMachineBlockElim to NPM (PR #136127)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-regalloc

Author: Akshat Oke (optimisan)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/136127.diff


6 Files Affected:

- (modified) llvm/include/llvm/CodeGen/UnreachableBlockElim.h (+8) 
- (modified) llvm/include/llvm/InitializePasses.h (+1-1) 
- (modified) llvm/include/llvm/Passes/MachinePassRegistry.def (+2) 
- (modified) llvm/lib/CodeGen/CodeGen.cpp (+1-1) 
- (modified) llvm/lib/CodeGen/LiveVariables.cpp (+1-1) 
- (modified) llvm/lib/CodeGen/UnreachableBlockElim.cpp (+50-17) 


``````````diff
diff --git a/llvm/include/llvm/CodeGen/UnreachableBlockElim.h b/llvm/include/llvm/CodeGen/UnreachableBlockElim.h
index 7dbae77e34401..3c2b701512df6 100644
--- a/llvm/include/llvm/CodeGen/UnreachableBlockElim.h
+++ b/llvm/include/llvm/CodeGen/UnreachableBlockElim.h
@@ -22,6 +22,7 @@
 #ifndef LLVM_CODEGEN_UNREACHABLEBLOCKELIM_H
 #define LLVM_CODEGEN_UNREACHABLEBLOCKELIM_H
 
+#include "llvm/CodeGen/MachinePassManager.h"
 #include "llvm/IR/PassManager.h"
 
 namespace llvm {
@@ -31,6 +32,13 @@ class UnreachableBlockElimPass
 public:
   PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
 };
+
+class UnreachableMachineBlockElimPass
+    : public PassInfoMixin<UnreachableMachineBlockElimPass> {
+public:
+  PreservedAnalyses run(MachineFunction &F, MachineFunctionAnalysisManager &AM);
+};
+
 } // end namespace llvm
 
 #endif // LLVM_CODEGEN_UNREACHABLEBLOCKELIM_H
diff --git a/llvm/include/llvm/InitializePasses.h b/llvm/include/llvm/InitializePasses.h
index 9fd8f8228a717..9bef8e496c57e 100644
--- a/llvm/include/llvm/InitializePasses.h
+++ b/llvm/include/llvm/InitializePasses.h
@@ -315,7 +315,7 @@ void initializeUniformityInfoWrapperPassPass(PassRegistry &);
 void initializeUnifyLoopExitsLegacyPassPass(PassRegistry &);
 void initializeUnpackMachineBundlesPass(PassRegistry &);
 void initializeUnreachableBlockElimLegacyPassPass(PassRegistry &);
-void initializeUnreachableMachineBlockElimPass(PassRegistry &);
+void initializeUnreachableMachineBlockElimLegacyPass(PassRegistry &);
 void initializeVerifierLegacyPassPass(PassRegistry &);
 void initializeVirtRegMapWrapperLegacyPass(PassRegistry &);
 void initializeVirtRegRewriterPass(PassRegistry &);
diff --git a/llvm/include/llvm/Passes/MachinePassRegistry.def b/llvm/include/llvm/Passes/MachinePassRegistry.def
index fff5083caad1a..5f7645fe65106 100644
--- a/llvm/include/llvm/Passes/MachinePassRegistry.def
+++ b/llvm/include/llvm/Passes/MachinePassRegistry.def
@@ -194,6 +194,8 @@ MACHINE_FUNCTION_PASS("stack-slot-coloring", StackSlotColoringPass())
 MACHINE_FUNCTION_PASS("tailduplication", TailDuplicatePass())
 MACHINE_FUNCTION_PASS("trigger-verifier-error", TriggerVerifierErrorPass())
 MACHINE_FUNCTION_PASS("two-address-instruction", TwoAddressInstructionPass())
+MACHINE_FUNCTION_PASS("unreachable-machine-block-elim", 
+                      UnreachableMachineBlockElimPass())
 MACHINE_FUNCTION_PASS("verify", MachineVerifierPass())
 MACHINE_FUNCTION_PASS("verify<machine-trace-metrics>", MachineTraceMetricsVerifierPass())
 MACHINE_FUNCTION_PASS("xray-instrumentation", XRayInstrumentationPass())
diff --git a/llvm/lib/CodeGen/CodeGen.cpp b/llvm/lib/CodeGen/CodeGen.cpp
index 2b0e93803971f..a34adcf4803c5 100644
--- a/llvm/lib/CodeGen/CodeGen.cpp
+++ b/llvm/lib/CodeGen/CodeGen.cpp
@@ -140,7 +140,7 @@ void llvm::initializeCodeGen(PassRegistry &Registry) {
   initializeTypePromotionLegacyPass(Registry);
   initializeUnpackMachineBundlesPass(Registry);
   initializeUnreachableBlockElimLegacyPassPass(Registry);
-  initializeUnreachableMachineBlockElimPass(Registry);
+  initializeUnreachableMachineBlockElimLegacyPass(Registry);
   initializeVirtRegMapWrapperLegacyPass(Registry);
   initializeVirtRegRewriterPass(Registry);
   initializeWasmEHPreparePass(Registry);
diff --git a/llvm/lib/CodeGen/LiveVariables.cpp b/llvm/lib/CodeGen/LiveVariables.cpp
index ab95200af00e0..f8e0583839b23 100644
--- a/llvm/lib/CodeGen/LiveVariables.cpp
+++ b/llvm/lib/CodeGen/LiveVariables.cpp
@@ -61,7 +61,7 @@ char LiveVariablesWrapperPass::ID = 0;
 char &llvm::LiveVariablesID = LiveVariablesWrapperPass::ID;
 INITIALIZE_PASS_BEGIN(LiveVariablesWrapperPass, "livevars",
                       "Live Variable Analysis", false, false)
-INITIALIZE_PASS_DEPENDENCY(UnreachableMachineBlockElim)
+INITIALIZE_PASS_DEPENDENCY(UnreachableMachineBlockElimLegacy)
 INITIALIZE_PASS_END(LiveVariablesWrapperPass, "livevars",
                     "Live Variable Analysis", false, false)
 
diff --git a/llvm/lib/CodeGen/UnreachableBlockElim.cpp b/llvm/lib/CodeGen/UnreachableBlockElim.cpp
index aa4ccec3338a9..f9f7b47160b6c 100644
--- a/llvm/lib/CodeGen/UnreachableBlockElim.cpp
+++ b/llvm/lib/CodeGen/UnreachableBlockElim.cpp
@@ -72,32 +72,58 @@ PreservedAnalyses UnreachableBlockElimPass::run(Function &F,
 }
 
 namespace {
-  class UnreachableMachineBlockElim : public MachineFunctionPass {
-    bool runOnMachineFunction(MachineFunction &F) override;
-    void getAnalysisUsage(AnalysisUsage &AU) const override;
-
-  public:
-    static char ID; // Pass identification, replacement for typeid
-    UnreachableMachineBlockElim() : MachineFunctionPass(ID) {}
-  };
-}
-char UnreachableMachineBlockElim::ID = 0;
+class UnreachableMachineBlockElim {
+  MachineDominatorTree *MDT;
+  MachineLoopInfo *MLI;
+
+public:
+  UnreachableMachineBlockElim(MachineDominatorTree *MDT, MachineLoopInfo *MLI)
+      : MDT(MDT), MLI(MLI) {}
+  bool run(MachineFunction &MF);
+};
+
+class UnreachableMachineBlockElimLegacy : public MachineFunctionPass {
+  bool runOnMachineFunction(MachineFunction &F) override;
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+
+public:
+  static char ID; // Pass identification, replacement for typeid
+  UnreachableMachineBlockElimLegacy() : MachineFunctionPass(ID) {}
+};
+} // namespace
+
+char UnreachableMachineBlockElimLegacy::ID = 0;
 
-INITIALIZE_PASS(UnreachableMachineBlockElim, "unreachable-mbb-elimination",
-  "Remove unreachable machine basic blocks", false, false)
+INITIALIZE_PASS(UnreachableMachineBlockElimLegacy,
+                "unreachable-mbb-elimination",
+                "Remove unreachable machine basic blocks", false, false)
 
-char &llvm::UnreachableMachineBlockElimID = UnreachableMachineBlockElim::ID;
+char &llvm::UnreachableMachineBlockElimID =
+    UnreachableMachineBlockElimLegacy::ID;
 
-void UnreachableMachineBlockElim::getAnalysisUsage(AnalysisUsage &AU) const {
+void UnreachableMachineBlockElimLegacy::getAnalysisUsage(
+    AnalysisUsage &AU) const {
   AU.addPreserved<MachineLoopInfoWrapperPass>();
   AU.addPreserved<MachineDominatorTreeWrapperPass>();
   MachineFunctionPass::getAnalysisUsage(AU);
 }
 
-bool UnreachableMachineBlockElim::runOnMachineFunction(MachineFunction &F) {
-  df_iterator_default_set<MachineBasicBlock*> Reachable;
-  bool ModifiedPHI = false;
+PreservedAnalyses
+UnreachableMachineBlockElimPass::run(MachineFunction &MF,
+                                     MachineFunctionAnalysisManager &AM) {
+  auto *MDT = AM.getCachedResult<MachineDominatorTreeAnalysis>(MF);
+  auto *MLI = AM.getCachedResult<MachineLoopAnalysis>(MF);
+
+  if (!UnreachableMachineBlockElim(MDT, MLI).run(MF))
+    return PreservedAnalyses::all();
+
+  return getMachineFunctionPassPreservedAnalyses()
+      .preserve<MachineLoopAnalysis>()
+      .preserve<MachineDominatorTreeAnalysis>();
+}
 
+bool UnreachableMachineBlockElimLegacy::runOnMachineFunction(
+    MachineFunction &MF) {
   MachineDominatorTreeWrapperPass *MDTWrapper =
       getAnalysisIfAvailable<MachineDominatorTreeWrapperPass>();
   MachineDominatorTree *MDT = MDTWrapper ? &MDTWrapper->getDomTree() : nullptr;
@@ -105,6 +131,13 @@ bool UnreachableMachineBlockElim::runOnMachineFunction(MachineFunction &F) {
       getAnalysisIfAvailable<MachineLoopInfoWrapperPass>();
   MachineLoopInfo *MLI = MLIWrapper ? &MLIWrapper->getLI() : nullptr;
 
+  return UnreachableMachineBlockElim(MDT, MLI).run(MF);
+}
+
+bool UnreachableMachineBlockElim::run(MachineFunction &F) {
+  df_iterator_default_set<MachineBasicBlock *> Reachable;
+  bool ModifiedPHI = false;
+
   // Mark all reachable blocks.
   for (MachineBasicBlock *BB : depth_first_ext(&F, Reachable))
     (void)BB/* Mark all reachable blocks */;

``````````

</details>


https://github.com/llvm/llvm-project/pull/136127