Move update code to MachineBasicBlock

Author: paperchalice

llvm/lib/CodeGen/MachineBasicBlock.cpp

@@ -16,11 +16,13 @@
 #include "llvm/CodeGen/LiveIntervals.h"
 #include "llvm/CodeGen/LivePhysRegs.h"
 #include "llvm/CodeGen/LiveVariables.h"
+#include "llvm/CodeGen/MachineDomTreeUpdater.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineJumpTableInfo.h"
 #include "llvm/CodeGen/MachineLoopInfo.h"
+#include "llvm/CodeGen/MachinePostDominators.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/SlotIndexes.h"
 #include "llvm/CodeGen/TargetInstrInfo.h"
@@ -1363,6 +1365,18 @@ MachineBasicBlock *MachineBasicBlock::SplitCriticalEdge(
       }
     }
 
+  auto *MDTWrapper =
+      P.getAnalysisIfAvailable<MachineDominatorTreeWrapperPass>();
+  auto *MPDTWrapper =
+      P.getAnalysisIfAvailable<MachinePostDominatorTreeWrapperPass>();
+  auto *MDT = MDTWrapper ? &MDTWrapper->getDomTree() : nullptr;
+  auto *MPDT = MPDTWrapper ? &MPDTWrapper->getPostDomTree() : nullptr;
+  MachineDomTreeUpdater MDTU(MDT, MPDT,
+                             MachineDomTreeUpdater::UpdateStrategy::Eager);
+  MDTU.applyUpdates({{MachineDominatorTree::Insert, this, NMBB},
+                     {MachineDominatorTree::Insert, NMBB, Succ},
+                     {MachineDominatorTree::Delete, this, Succ}});
+
   return NMBB;
 }
 

llvm/lib/CodeGen/MachineSink.cpp

@@ -30,7 +30,6 @@
 #include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
 #include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
 #include "llvm/CodeGen/MachineCycleAnalysis.h"
-#include "llvm/CodeGen/MachineDomTreeUpdater.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
@@ -722,10 +721,6 @@ bool MachineSinking::runOnMachineFunction(MachineFunction &MF) {
   bool EverMadeChange = false;
 
   while (true) {
-    // Ensure that the dominant tree is up-to-date after splitting the critical
-    // edge.
-    MachineDomTreeUpdater MDTU(DT, PDT,
-                               MachineDomTreeUpdater::UpdateStrategy::Lazy);
     bool MadeChange = false;
 
     // Process all basic blocks.
@@ -748,11 +743,6 @@ bool MachineSinking::runOnMachineFunction(MachineFunction &MF) {
         MadeChange = true;
         ++NumSplit;
         CI->splitCriticalEdge(Pair.first, Pair.second, NewSucc);
-
-        MDTU.applyUpdates(
-            {{MachineDominatorTree::Insert, Pair.first, NewSucc},
-             {MachineDominatorTree::Insert, NewSucc, Pair.second},
-             {MachineDominatorTree::Delete, Pair.first, Pair.second}});
       } else
         LLVM_DEBUG(dbgs() << " *** Not legal to break critical edge\n");
     }

llvm/lib/CodeGen/PHIElimination.cpp

@@ -21,7 +21,6 @@
 #include "llvm/CodeGen/LiveIntervals.h"
 #include "llvm/CodeGen/LiveVariables.h"
 #include "llvm/CodeGen/MachineBasicBlock.h"
-#include "llvm/CodeGen/MachineDomTreeUpdater.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
@@ -96,8 +95,7 @@ namespace {
     /// Split critical edges where necessary for good coalescer performance.
     bool SplitPHIEdges(MachineFunction &MF, MachineBasicBlock &MBB,
                        MachineLoopInfo *MLI,
-                       std::vector<SparseBitVector<>> *LiveInSets,
-                       MachineDomTreeUpdater *MDTU);
+                       std::vector<SparseBitVector<>> *LiveInSets);
 
     // These functions are temporary abstractions around LiveVariables and
     // LiveIntervals, so they can go away when LiveVariables does.
@@ -185,13 +183,8 @@ bool PHIElimination::runOnMachineFunction(MachineFunction &MF) {
     }
 
     MachineLoopInfo *MLI = getAnalysisIfAvailable<MachineLoopInfo>();
-    auto *DTWrapper = getAnalysisIfAvailable<MachineDominatorTreeWrapperPass>();
-    MachineDominatorTree *MDT = DTWrapper ? &DTWrapper->getDomTree() : nullptr;
-    MachineDomTreeUpdater MDTU(MDT,
-                               MachineDomTreeUpdater::UpdateStrategy::Lazy);
     for (auto &MBB : MF)
-      Changed |= SplitPHIEdges(MF, MBB, MLI, (LV ? &LiveInSets : nullptr),
-                               DTWrapper ? &MDTU : nullptr);
+      Changed |= SplitPHIEdges(MF, MBB, MLI, (LV ? &LiveInSets : nullptr));
   }
 
   // This pass takes the function out of SSA form.
@@ -677,8 +670,7 @@ void PHIElimination::analyzePHINodes(const MachineFunction& MF) {
 
 bool PHIElimination::SplitPHIEdges(MachineFunction &MF, MachineBasicBlock &MBB,
                                    MachineLoopInfo *MLI,
-                                   std::vector<SparseBitVector<>> *LiveInSets,
-                                   MachineDomTreeUpdater *MDTU) {
+                                   std::vector<SparseBitVector<>> *LiveInSets) {
   if (MBB.empty() || !MBB.front().isPHI() || MBB.isEHPad())
     return false;   // Quick exit for basic blocks without PHIs.
 
@@ -745,12 +737,7 @@ bool PHIElimination::SplitPHIEdges(MachineFunction &MF, MachineBasicBlock &MBB,
       }
       if (!ShouldSplit && !SplitAllCriticalEdges)
         continue;
-      if (auto *NewMBB = PreMBB->SplitCriticalEdge(&MBB, *this, LiveInSets)) {
-        if (MDTU)
-          MDTU->applyUpdates({{MachineDominatorTree::Insert, PreMBB, NewMBB},
-                              {MachineDominatorTree::Insert, NewMBB, &MBB},
-                              {MachineDominatorTree::Delete, PreMBB, &MBB}});
-      } else {
+      if (!PreMBB->SplitCriticalEdge(&MBB, *this, LiveInSets)) {
         LLVM_DEBUG(dbgs() << "Failed to split critical edge.\n");
         continue;
       }