RegAllocGreedy: Properly initialize this pass, so that -run-pass will work

[davide]

This seems reasonable. Are you aware of other passes that don't use INITIALIZE_PASS without a good reason?
@MatzeB pointed out earlier on IRC InstPrinter but that's not quite easy to fix.

[MatzeB]

LGTM.

lib/CodeGen/RegAllocGreedy.cpp

433 ↗

(On Diff #77702)

duplicate

434–442 ↗

(On Diff #77702)

There are a number of passes in here that I would not expect (I would only expect the stuff from getAnalysisUsage() here). But I see this was just copied from the constructor, which was equally strange.

So I guess we can leave the cleanup of this list for another commit.

[MatzeB]

In D26572#593502, @davide wrote:

This seems reasonable. Are you aware of other passes that don't use INITIALIZE_PASS without a good reason?

For example RABasic, I am sure you will find more. Patches highly welcome :)

[qcolombet]

Yay!

It was on my todo list and did not have time to do it yet.

Thanks,
-Quentin

llvm/trunk/include/llvm/CodeGen/Passes.h

/// MachineDominanaceFrontier - This pass is a machine dominators analysis pass.
   /// SpillPlacement analysis. Suggest optimal placement of spill code between
   /// basic blocks.
   extern char &SpillPlacementID;
 
   /// ShrinkWrap pass. Look for the best place to insert save and restore
   // instruction and update the MachineFunctionInfo with that information.
   extern char &ShrinkWrapID;
 
+  /// Greedy register allocator.
+  extern char &RAGreedyID;
+
   /// VirtRegRewriter pass. Rewrite virtual registers to physical registers as
   /// assigned in VirtRegMap.
   extern char &VirtRegRewriterID;
 
   /// UnreachableMachineBlockElimination - This pass removes unreachable
   /// machine basic blocks.
   extern char &UnreachableMachineBlockElimID;
 

llvm/trunk/include/llvm/InitializePasses.h

 void initializeDominatorTreeWrapperPassPass(PassRegistry&);
 void initializeDwarfEHPreparePass(PassRegistry&);
 void initializeEarlyCSELegacyPassPass(PassRegistry &);
 void initializeEarlyCSEMemSSALegacyPassPass(PassRegistry &);
 void initializeEarlyIfConverterPass(PassRegistry&);
 void initializeEdgeBundlesPass(PassRegistry&);
 void initializeEfficiencySanitizerPass(PassRegistry&);
 void initializeEliminateAvailableExternallyLegacyPassPass(PassRegistry &);
+void initializeRAGreedyPass(PassRegistry&);
 void initializeGVNHoistLegacyPassPass(PassRegistry &);
 void initializeExpandISelPseudosPass(PassRegistry&);
 void initializeExpandPostRAPass(PassRegistry&);
 void initializeExternalAAWrapperPassPass(PassRegistry&);
 void initializeFinalizeMachineBundlesPass(PassRegistry&);
 void initializeFlattenCFGPassPass(PassRegistry&);
 void initializeFloat2IntLegacyPassPass(PassRegistry&);
 void initializeForceFunctionAttrsLegacyPassPass(PassRegistry&);

llvm/trunk/lib/CodeGen/CodeGen.cpp

void llvm::initializeCodeGen(PassRegistry &Registry) {
   initializePEIPass(Registry);
   initializePHIEliminationPass(Registry);
   initializePeepholeOptimizerPass(Registry);
   initializePostMachineSchedulerPass(Registry);
   initializePostRAHazardRecognizerPass(Registry);
   initializePostRASchedulerPass(Registry);
   initializePreISelIntrinsicLoweringLegacyPassPass(Registry);
   initializeProcessImplicitDefsPass(Registry);
+  initializeRAGreedyPass(Registry);
   initializeRegisterCoalescerPass(Registry);
   initializeRenameIndependentSubregsPass(Registry);
   initializeShrinkWrapPass(Registry);
   initializeSlotIndexesPass(Registry);
   initializeStackColoringPass(Registry);
   initializeStackMapLivenessPass(Registry);
   initializeLiveDebugValuesPass(Registry);
   initializeSafeStackPass(Registry);

llvm/trunk/lib/CodeGen/RegAllocGreedy.cpp

private:
   BlockFrequency getBrokenHintFreq(const HintsInfo &, unsigned);
   void collectHintInfo(unsigned, HintsInfo &);
 
   bool isUnusedCalleeSavedReg(unsigned PhysReg) const;
 };
 } // end anonymous namespace
 
 char RAGreedy::ID = 0;
+char &llvm::RAGreedyID = RAGreedy::ID;
+
+INITIALIZE_PASS_BEGIN(RAGreedy, "greedy",
+                "Greedy Register Allocator", false, false)
+INITIALIZE_PASS_DEPENDENCY(LiveDebugVariables)
+INITIALIZE_PASS_DEPENDENCY(SlotIndexes)
+INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
+INITIALIZE_PASS_DEPENDENCY(RegisterCoalescer)
+INITIALIZE_PASS_DEPENDENCY(MachineScheduler)
+INITIALIZE_PASS_DEPENDENCY(LiveStacks)
+INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
+INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
+INITIALIZE_PASS_DEPENDENCY(VirtRegMap)
+INITIALIZE_PASS_DEPENDENCY(LiveRegMatrix)
+INITIALIZE_PASS_DEPENDENCY(EdgeBundles)
+INITIALIZE_PASS_DEPENDENCY(SpillPlacement)
+INITIALIZE_PASS_END(RAGreedy, "greedy",
+                "Greedy Register Allocator", false, false)
 
 #ifndef NDEBUG
 const char *const RAGreedy::StageName[] = {
     "RS_New",
     "RS_Assign",
     "RS_Split",
     "RS_Split2",
     "RS_Spill",
     "RS_Memory",
     "RS_Done"
 };
 #endif
 
 // Hysteresis to use when comparing floats.
 // This helps stabilize decisions based on float comparisons.
 const float Hysteresis = (2007 / 2048.0f); // 0.97998046875
 
 
 FunctionPass* llvm::createGreedyRegisterAllocator() {
   return new RAGreedy();
 }
 
 RAGreedy::RAGreedy(): MachineFunctionPass(ID) {
-  initializeLiveDebugVariablesPass(*PassRegistry::getPassRegistry());
-  initializeSlotIndexesPass(*PassRegistry::getPassRegistry());
-  initializeLiveIntervalsPass(*PassRegistry::getPassRegistry());
-  initializeSlotIndexesPass(*PassRegistry::getPassRegistry());
-  initializeRegisterCoalescerPass(*PassRegistry::getPassRegistry());
-  initializeMachineSchedulerPass(*PassRegistry::getPassRegistry());
-  initializeLiveStacksPass(*PassRegistry::getPassRegistry());
-  initializeMachineDominatorTreePass(*PassRegistry::getPassRegistry());
-  initializeMachineLoopInfoPass(*PassRegistry::getPassRegistry());
-  initializeVirtRegMapPass(*PassRegistry::getPassRegistry());
-  initializeLiveRegMatrixPass(*PassRegistry::getPassRegistry());
-  initializeEdgeBundlesPass(*PassRegistry::getPassRegistry());
-  initializeSpillPlacementPass(*PassRegistry::getPassRegistry());
 }
 
 void RAGreedy::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.setPreservesCFG();
   AU.addRequired<MachineBlockFrequencyInfo>();
   AU.addPreserved<MachineBlockFrequencyInfo>();
   AU.addRequired<AAResultsWrapperPass>();
   AU.addPreserved<AAResultsWrapperPass>();

llvm/trunk/test/CodeGen/MIR/Generic/runPass.mir

+# RUN: llc -run-pass=greedy -debug-pass=Arguments -o - %s 2>&1 | FileCheck %s
+
+# Check that passes are initialized correctly, so that it's possible to
+# use -run-pass.
+
+---
+# CHECK: name: foo
+name: foo
+body: |
+  bb.0:
+...