[CodeGen] Remove FinalizeMachineBundles pass (#149806)

Replace its only use in the AMDGPU R600 backend with a call to
finalizeBundles.

Author: jayfoad

llvm/docs/ReleaseNotes.md

@@ -86,6 +86,8 @@ Changes to LLVM infrastructure
 * Added the support for ``fmaximum`` and ``fminimum`` in ``atomicrmw`` instruction. The
   comparison is expected to match the behavior of ``llvm.maximum.*`` and
   ``llvm.minimum.*`` respectively.
+* Removed the codegen pass ``finalize-mi-bundles``. The same functionality is
+  still available as an API function ``llvm::finalizeBundles``.
 
 Changes to building LLVM
 ------------------------

llvm/include/llvm/CodeGen/Passes.h

@@ -438,10 +438,6 @@ LLVM_ABI extern char &UnpackMachineBundlesID;
 LLVM_ABI FunctionPass *
 createUnpackMachineBundles(std::function<bool(const MachineFunction &)> Ftor);
 
-/// FinalizeMachineBundles - This pass finalize machine instruction
-/// bundles (created earlier, e.g. during pre-RA scheduling).
-LLVM_ABI extern char &FinalizeMachineBundlesID;
-
 /// StackMapLiveness - This pass analyses the register live-out set of
 /// stackmap/patchpoint intrinsics and attaches the calculated information to
 /// the intrinsic for later emission to the StackMap.

llvm/include/llvm/InitializePasses.h

@@ -119,7 +119,6 @@ LLVM_ABI void initializeExpandVariadicsPass(PassRegistry &);
 LLVM_ABI void initializeExternalAAWrapperPassPass(PassRegistry &);
 LLVM_ABI void initializeFEntryInserterLegacyPass(PassRegistry &);
 LLVM_ABI void initializeFinalizeISelPass(PassRegistry &);
-LLVM_ABI void initializeFinalizeMachineBundlesPass(PassRegistry &);
 LLVM_ABI void initializeFixIrreduciblePass(PassRegistry &);
 LLVM_ABI void initializeFixupStatepointCallerSavedLegacyPass(PassRegistry &);
 LLVM_ABI void initializeFlattenCFGLegacyPassPass(PassRegistry &);

llvm/lib/CodeGen/CodeGen.cpp

@@ -45,7 +45,6 @@ void llvm::initializeCodeGen(PassRegistry &Registry) {
   initializeExpandPostRALegacyPass(Registry);
   initializeFEntryInserterLegacyPass(Registry);
   initializeFinalizeISelPass(Registry);
-  initializeFinalizeMachineBundlesPass(Registry);
   initializeFixupStatepointCallerSavedLegacyPass(Registry);
   initializeFuncletLayoutPass(Registry);
   initializeGCMachineCodeAnalysisPass(Registry);

llvm/lib/CodeGen/MachineInstrBundle.cpp

@@ -83,27 +83,6 @@ llvm::createUnpackMachineBundles(
   return new UnpackMachineBundles(std::move(Ftor));
 }
 
-namespace {
-  class FinalizeMachineBundles : public MachineFunctionPass {
-  public:
-    static char ID; // Pass identification
-    FinalizeMachineBundles() : MachineFunctionPass(ID) {
-      initializeFinalizeMachineBundlesPass(*PassRegistry::getPassRegistry());
-    }
-
-    bool runOnMachineFunction(MachineFunction &MF) override;
-  };
-} // end anonymous namespace
-
-char FinalizeMachineBundles::ID = 0;
-char &llvm::FinalizeMachineBundlesID = FinalizeMachineBundles::ID;
-INITIALIZE_PASS(FinalizeMachineBundles, "finalize-mi-bundles",
-                "Finalize machine instruction bundles", false, false)
-
-bool FinalizeMachineBundles::runOnMachineFunction(MachineFunction &MF) {
-  return llvm::finalizeBundles(MF);
-}
-
 /// Return the first found DebugLoc that has a DILocation, given a range of
 /// instructions. The search range is from FirstMI to LastMI (exclusive). If no
 /// DILocation is found, then an empty location is returned.

llvm/lib/Target/AMDGPU/R600ExpandSpecialInstrs.cpp

@@ -270,5 +270,6 @@ bool R600ExpandSpecialInstrsPass::runOnMachineFunction(MachineFunction &MF) {
       MI.eraseFromParent();
     }
   }
+  finalizeBundles(MF);
   return false;
 }

llvm/lib/Target/AMDGPU/R600TargetMachine.cpp

@@ -138,7 +138,6 @@ void R600PassConfig::addPreSched2() {
 void R600PassConfig::addPreEmitPass() {
   addPass(createR600MachineCFGStructurizerPass());
   addPass(createR600ExpandSpecialInstrsPass());
-  addPass(&FinalizeMachineBundlesID);
   addPass(createR600Packetizer());
   addPass(createR600ControlFlowFinalizer());
 }