Merge llvm-project 12.0.1 release and follow-up fixes

Merge llvm-project main llvmorg-12-init-17869-g8e464dd76bef

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12-init-17869-g8e464dd76bef, the last commit before the
upstream release/12.x branch was created.

PR:		255570

(cherry picked from commit e8d8bef961a50d4dc22501cde4fb9fb0be1b2532)

Merge llvm-project 12.0.0 release

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12.0.0-0-gd28af7c654d8, a.k.a. 12.0.0 release.

PR:		255570

(cherry picked from commit d409305fa3838fb39b38c26fc085fb729b8766d5)

Disable strict-fp for powerpcspe, as it does not work properly yet

Merge commit 5c18d1136665 from llvm git (by Qiu Chaofan)

  [SPE] Disable strict-fp for SPE by default

  As discussed in PR50385, strict-fp on PowerPC SPE has not been
  handled well. This patch disables it by default for SPE.

  Reviewed By: nemanjai, vit9696, jhibbits

  Differential Revision: https://reviews.llvm.org/D103235

PR:		255570

(cherry picked from commit 715df83abc049b23d9acddc81f2480bd4c056d64)

Apply upstream libc++ fix to allow building with devel/xxx-xtoolchain-gcc

Merge commit 52e9d80d5db2 from llvm git (by Jason Liu):

  [libc++] add `inline` for __open's definition in ifstream and ofstream

  Summary:

  When building with gcc on AIX, it seems that gcc does not like the
  `always_inline` without the `inline` keyword.
  So adding the inline keywords in for __open in ifstream and ofstream.
  That will also make it consistent with __open in basic_filebuf
  (it seems we added `inline` there before for gcc build as well).

  Differential Revision: https://reviews.llvm.org/D99422

PR:		255570

(cherry picked from commit d099db25464b826c5724cf2fb5b22292bbe15f6e)

Undefine HAVE_(DE)REGISTER_FRAME in llvm's config.h on arm

Otherwise, the lli tool (enable by WITH_CLANG_EXTRAS) won't link on arm,
stating that __register_frame is undefined. This function is normally
provided by libunwind, but explicitly not for the ARM Exception ABI.

Reported by:	oh
PR:		255570

(cherry picked from commit f336b45e943c7f9a90ffcea1a6c4c7039e54c73c)

Merge llvm-project 12.0.1 rc2

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12.0.1-rc2-0-ge7dac564cd0e, a.k.a. 12.0.1 rc2.

PR:		255570

(cherry picked from commit 23408297fbf3089f0388a8873b02fa75ab3f5bb9)

Revert libunwind change to fix backtrace segfault on aarch64

Revert commit 22b615a96593 from llvm git (by Daniel Kiss):

  [libunwind] Support for leaf function unwinding.

  Unwinding leaf function is useful in cases when the backtrace finds a
  leaf function for example when it caused a signal.
  This patch also add the support for the DW_CFA_undefined because it marks
  the end of the frames.

  Ryan Prichard provided code for the tests.

  Reviewed By: #libunwind, mstorsjo

  Differential Revision: https://reviews.llvm.org/D83573

  Reland with limit the test to the x86_64-linux target.

Bisection has shown that this particular upstream commit causes programs
using backtrace(3) on aarch64 to segfault. This affects the lang/rust
port, for instance. Until we can upstream to fix this problem, revert
the commit for now.

Reported by:	mikael
PR:		256864

(cherry picked from commit 5866c369e4fd917c0d456f0f10b92ee354b82279)

Merge llvm-project 12.0.1 release

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12.0.1-0-gfed41342a82f, a.k.a. 12.0.1 release.

PR:		255570

(cherry picked from commit 4652422eb477731f284b1345afeefef7f269da50)

compilert-rt: build out-of-line LSE atomics helpers for aarch64

Both clang >= 12 and gcc >= 10.1 now default to -moutline-atomics for
aarch64. This requires a bunch of helper functions in libcompiler_rt.a,
to avoid link errors like "undefined symbol: __aarch64_ldadd8_acq_rel".

(Note: of course you can use -mno-outline-atomics as a workaround too,
but this would negate the potential performance benefit of the faster
LSE instructions.)

Bump __FreeBSD_version so ports maintainers can easily detect this.

PR:		257392

(cherry picked from commit cc55ee8009a550810d38777fd6ace9abf3a2f6b4)

1 files changed, 256 insertions, 34 deletions

diff --git a/contrib/llvm-project/llvm/lib/CodeGen/MachineSink.cpp b/contrib/llvm-project/llvm/lib/CodeGen/MachineSink.cpp
index 5f958bbc31b7..378df1b75e25 100644
--- a/contrib/llvm-project/llvm/lib/CodeGen/MachineSink.cpp
+++ b/contrib/llvm-project/llvm/lib/CodeGen/MachineSink.cpp
@@ -34,6 +34,8 @@
 #include "llvm/CodeGen/MachineOperand.h"
 #include "llvm/CodeGen/MachinePostDominators.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/RegisterClassInfo.h"
+#include "llvm/CodeGen/RegisterPressure.h"
 #include "llvm/CodeGen/TargetInstrInfo.h"
 #include "llvm/CodeGen/TargetRegisterInfo.h"
 #include "llvm/CodeGen/TargetSubtargetInfo.h"
@@ -77,6 +79,18 @@ static cl::opt<unsigned> SplitEdgeProbabilityThreshold(
         "splitted critical edge"),
     cl::init(40), cl::Hidden);
 
+static cl::opt<unsigned> SinkLoadInstsPerBlockThreshold(
+    "machine-sink-load-instrs-threshold",
+    cl::desc("Do not try to find alias store for a load if there is a in-path "
+             "block whose instruction number is higher than this threshold."),
+    cl::init(2000), cl::Hidden);
+
+static cl::opt<unsigned> SinkLoadBlocksThreshold(
+    "machine-sink-load-blocks-threshold",
+    cl::desc("Do not try to find alias store for a load if the block number in "
+             "the straight line is higher than this threshold."),
+    cl::init(20), cl::Hidden);
+
 STATISTIC(NumSunk,      "Number of machine instructions sunk");
 STATISTIC(NumSplit,     "Number of critical edges split");
 STATISTIC(NumCoalesces, "Number of copies coalesced");
@@ -94,6 +108,7 @@ namespace {
     MachineBlockFrequencyInfo *MBFI;
     const MachineBranchProbabilityInfo *MBPI;
     AliasAnalysis *AA;
+    RegisterClassInfo RegClassInfo;
 
     // Remember which edges have been considered for breaking.
     SmallSet<std::pair<MachineBasicBlock*, MachineBasicBlock*>, 8>
@@ -127,6 +142,15 @@ namespace {
     /// current block.
     DenseSet<DebugVariable> SeenDbgVars;
 
+    std::map<std::pair<MachineBasicBlock *, MachineBasicBlock *>, bool>
+        HasStoreCache;
+    std::map<std::pair<MachineBasicBlock *, MachineBasicBlock *>,
+             std::vector<MachineInstr *>>
+        StoreInstrCache;
+
+    /// Cached BB's register pressure.
+    std::map<MachineBasicBlock *, std::vector<unsigned>> CachedRegisterPressure;
+
   public:
     static char ID; // Pass identification
 
@@ -159,6 +183,9 @@ namespace {
                                      MachineBasicBlock *From,
                                      MachineBasicBlock *To);
 
+    bool hasStoreBetween(MachineBasicBlock *From, MachineBasicBlock *To,
+                         MachineInstr &MI);
+
     /// Postpone the splitting of the given critical
     /// edge (\p From, \p To).
     ///
@@ -184,12 +211,12 @@ namespace {
     /// to the copy source.
     void SalvageUnsunkDebugUsersOfCopy(MachineInstr &,
                                        MachineBasicBlock *TargetBlock);
-    bool AllUsesDominatedByBlock(unsigned Reg, MachineBasicBlock *MBB,
-                                 MachineBasicBlock *DefMBB,
-                                 bool &BreakPHIEdge, bool &LocalUse) const;
+    bool AllUsesDominatedByBlock(Register Reg, MachineBasicBlock *MBB,
+                                 MachineBasicBlock *DefMBB, bool &BreakPHIEdge,
+                                 bool &LocalUse) const;
     MachineBasicBlock *FindSuccToSinkTo(MachineInstr &MI, MachineBasicBlock *MBB,
                bool &BreakPHIEdge, AllSuccsCache &AllSuccessors);
-    bool isProfitableToSinkTo(unsigned Reg, MachineInstr &MI,
+    bool isProfitableToSinkTo(Register Reg, MachineInstr &MI,
                               MachineBasicBlock *MBB,
                               MachineBasicBlock *SuccToSinkTo,
                               AllSuccsCache &AllSuccessors);
@@ -200,6 +227,8 @@ namespace {
     SmallVector<MachineBasicBlock *, 4> &
     GetAllSortedSuccessors(MachineInstr &MI, MachineBasicBlock *MBB,
                            AllSuccsCache &AllSuccessors) const;
+
+    std::vector<unsigned> &getBBRegisterPressure(MachineBasicBlock &MBB);
   };
 
 } // end anonymous namespace
@@ -253,12 +282,11 @@ bool MachineSinking::PerformTrivialForwardCoalescing(MachineInstr &MI,
 /// occur in blocks dominated by the specified block. If any use is in the
 /// definition block, then return false since it is never legal to move def
 /// after uses.
-bool
-MachineSinking::AllUsesDominatedByBlock(unsigned Reg,
-                                        MachineBasicBlock *MBB,
-                                        MachineBasicBlock *DefMBB,
-                                        bool &BreakPHIEdge,
-                                        bool &LocalUse) const {
+bool MachineSinking::AllUsesDominatedByBlock(Register Reg,
+                                             MachineBasicBlock *MBB,
+                                             MachineBasicBlock *DefMBB,
+                                             bool &BreakPHIEdge,
+                                             bool &LocalUse) const {
   assert(Register::isVirtualRegister(Reg) && "Only makes sense for vregs");
 
   // Ignore debug uses because debug info doesn't affect the code.
@@ -327,6 +355,7 @@ bool MachineSinking::runOnMachineFunction(MachineFunction &MF) {
   MBFI = UseBlockFreqInfo ? &getAnalysis<MachineBlockFrequencyInfo>() : nullptr;
   MBPI = &getAnalysis<MachineBranchProbabilityInfo>();
   AA = &getAnalysis<AAResultsWrapperPass>().getAAResults();
+  RegClassInfo.runOnMachineFunction(MF);
 
   bool EverMadeChange = false;
 
@@ -347,11 +376,9 @@ bool MachineSinking::runOnMachineFunction(MachineFunction &MF) {
                           << printMBBReference(*Pair.first) << " -- "
                           << printMBBReference(*NewSucc) << " -- "
                           << printMBBReference(*Pair.second) << '\n');
-        if (MBFI) {
-          auto NewSuccFreq = MBFI->getBlockFreq(Pair.first) *
-                             MBPI->getEdgeProbability(Pair.first, NewSucc);
-          MBFI->setBlockFreq(NewSucc, NewSuccFreq.getFrequency());
-        }
+        if (MBFI)
+          MBFI->onEdgeSplit(*Pair.first, *NewSucc, *MBPI);
+
         MadeChange = true;
         ++NumSplit;
       } else
@@ -362,6 +389,9 @@ bool MachineSinking::runOnMachineFunction(MachineFunction &MF) {
     EverMadeChange = true;
   }
 
+  HasStoreCache.clear();
+  StoreInstrCache.clear();
+
   // Now clear any kill flags for recorded registers.
   for (auto I : RegsToClearKillFlags)
     MRI->clearKillFlags(I);
@@ -419,6 +449,8 @@ bool MachineSinking::ProcessBlock(MachineBasicBlock &MBB) {
 
   SeenDbgUsers.clear();
   SeenDbgVars.clear();
+  // recalculate the bb register pressure after sinking one BB.
+  CachedRegisterPressure.clear();
 
   return MadeChange;
 }
@@ -430,7 +462,7 @@ void MachineSinking::ProcessDbgInst(MachineInstr &MI) {
 
   DebugVariable Var(MI.getDebugVariable(), MI.getDebugExpression(),
                     MI.getDebugLoc()->getInlinedAt());
-  bool SeenBefore = SeenDbgVars.count(Var) != 0;
+  bool SeenBefore = SeenDbgVars.contains(Var);
 
   MachineOperand &MO = MI.getDebugOperand(0);
   if (MO.isReg() && MO.getReg().isVirtual())
@@ -561,8 +593,44 @@ bool MachineSinking::PostponeSplitCriticalEdge(MachineInstr &MI,
   return true;
 }
 
+std::vector<unsigned> &
+MachineSinking::getBBRegisterPressure(MachineBasicBlock &MBB) {
+  // Currently to save compiling time, MBB's register pressure will not change
+  // in one ProcessBlock iteration because of CachedRegisterPressure. but MBB's
+  // register pressure is changed after sinking any instructions into it.
+  // FIXME: need a accurate and cheap register pressure estiminate model here.
+  auto RP = CachedRegisterPressure.find(&MBB);
+  if (RP != CachedRegisterPressure.end())
+    return RP->second;
+
+  RegionPressure Pressure;
+  RegPressureTracker RPTracker(Pressure);
+
+  // Initialize the register pressure tracker.
+  RPTracker.init(MBB.getParent(), &RegClassInfo, nullptr, &MBB, MBB.end(),
+                 /*TrackLaneMasks*/ false, /*TrackUntiedDefs=*/true);
+
+  for (MachineBasicBlock::iterator MII = MBB.instr_end(),
+                                   MIE = MBB.instr_begin();
+       MII != MIE; --MII) {
+    MachineInstr &MI = *std::prev(MII);
+    if (MI.isDebugValue() || MI.isDebugLabel())
+      continue;
+    RegisterOperands RegOpers;
+    RegOpers.collect(MI, *TRI, *MRI, false, false);
+    RPTracker.recedeSkipDebugValues();
+    assert(&*RPTracker.getPos() == &MI && "RPTracker sync error!");
+    RPTracker.recede(RegOpers);
+  }
+
+  RPTracker.closeRegion();
+  auto It = CachedRegisterPressure.insert(
+      std::make_pair(&MBB, RPTracker.getPressure().MaxSetPressure));
+  return It.first->second;
+}
+
 /// isProfitableToSinkTo - Return true if it is profitable to sink MI.
-bool MachineSinking::isProfitableToSinkTo(unsigned Reg, MachineInstr &MI,
+bool MachineSinking::isProfitableToSinkTo(Register Reg, MachineInstr &MI,
                                           MachineBasicBlock *MBB,
                                           MachineBasicBlock *SuccToSinkTo,
                                           AllSuccsCache &AllSuccessors) {
@@ -598,9 +666,73 @@ bool MachineSinking::isProfitableToSinkTo(unsigned Reg, MachineInstr &MI,
           FindSuccToSinkTo(MI, SuccToSinkTo, BreakPHIEdge, AllSuccessors))
     return isProfitableToSinkTo(Reg, MI, SuccToSinkTo, MBB2, AllSuccessors);
 
-  // If SuccToSinkTo is final destination and it is a post dominator of current
-  // block then it is not profitable to sink MI into SuccToSinkTo block.
-  return false;
+  MachineLoop *ML = LI->getLoopFor(MBB);
+
+  // If the instruction is not inside a loop, it is not profitable to sink MI to
+  // a post dominate block SuccToSinkTo.
+  if (!ML)
+    return false;
+
+  auto isRegisterPressureSetExceedLimit = [&](const TargetRegisterClass *RC) {
+    unsigned Weight = TRI->getRegClassWeight(RC).RegWeight;
+    const int *PS = TRI->getRegClassPressureSets(RC);
+    // Get register pressure for block SuccToSinkTo.
+    std::vector<unsigned> BBRegisterPressure =
+        getBBRegisterPressure(*SuccToSinkTo);
+    for (; *PS != -1; PS++)
+      // check if any register pressure set exceeds limit in block SuccToSinkTo
+      // after sinking.
+      if (Weight + BBRegisterPressure[*PS] >=
+          TRI->getRegPressureSetLimit(*MBB->getParent(), *PS))
+        return true;
+    return false;
+  };
+
+  // If this instruction is inside a loop and sinking this instruction can make
+  // more registers live range shorten, it is still prifitable.
+  for (unsigned i = 0, e = MI.getNumOperands(); i != e; ++i) {
+    const MachineOperand &MO = MI.getOperand(i);
+    // Ignore non-register operands.
+    if (!MO.isReg())
+      continue;
+    Register Reg = MO.getReg();
+    if (Reg == 0)
+      continue;
+
+    // Don't handle physical register.
+    if (Register::isPhysicalRegister(Reg))
+      return false;
+
+    // Users for the defs are all dominated by SuccToSinkTo.
+    if (MO.isDef()) {
+      // This def register's live range is shortened after sinking.
+      bool LocalUse = false;
+      if (!AllUsesDominatedByBlock(Reg, SuccToSinkTo, MBB, BreakPHIEdge,
+                                   LocalUse))
+        return false;
+    } else {
+      MachineInstr *DefMI = MRI->getVRegDef(Reg);
+      // DefMI is defined outside of loop. There should be no live range
+      // impact for this operand. Defination outside of loop means:
+      // 1: defination is outside of loop.
+      // 2: defination is in this loop, but it is a PHI in the loop header.
+      if (LI->getLoopFor(DefMI->getParent()) != ML ||
+          (DefMI->isPHI() && LI->isLoopHeader(DefMI->getParent())))
+        continue;
+      // The DefMI is defined inside the loop.
+      // If sinking this operand makes some register pressure set exceed limit,
+      // it is not profitable.
+      if (isRegisterPressureSetExceedLimit(MRI->getRegClass(Reg))) {
+        LLVM_DEBUG(dbgs() << "register pressure exceed limit, not profitable.");
+        return false;
+      }
+    }
+  }
+
+  // If MI is in loop and all its operands are alive across the whole loop or if
+  // no operand sinking make register pressure set exceed limit, it is
+  // profitable to sink MI.
+  return true;
 }
 
 /// Get the sorted sequence of successors for this MachineBasicBlock, possibly
@@ -613,8 +745,7 @@ MachineSinking::GetAllSortedSuccessors(MachineInstr &MI, MachineBasicBlock *MBB,
   if (Succs != AllSuccessors.end())
     return Succs->second;
 
-  SmallVector<MachineBasicBlock *, 4> AllSuccs(MBB->succ_begin(),
-                                               MBB->succ_end());
+  SmallVector<MachineBasicBlock *, 4> AllSuccs(MBB->successors());
 
   // Handle cases where sinking can happen but where the sink point isn't a
   // successor. For example:
@@ -876,6 +1007,97 @@ static void performSink(MachineInstr &MI, MachineBasicBlock &SuccToSinkTo,
   }
 }
 
+/// hasStoreBetween - check if there is store betweeen straight line blocks From
+/// and To.
+bool MachineSinking::hasStoreBetween(MachineBasicBlock *From,
+                                     MachineBasicBlock *To, MachineInstr &MI) {
+  // Make sure From and To are in straight line which means From dominates To
+  // and To post dominates From.
+  if (!DT->dominates(From, To) || !PDT->dominates(To, From))
+    return true;
+
+  auto BlockPair = std::make_pair(From, To);
+
+  // Does these two blocks pair be queried before and have a definite cached
+  // result?
+  if (HasStoreCache.find(BlockPair) != HasStoreCache.end())
+    return HasStoreCache[BlockPair];
+
+  if (StoreInstrCache.find(BlockPair) != StoreInstrCache.end())
+    return llvm::any_of(StoreInstrCache[BlockPair], [&](MachineInstr *I) {
+      return I->mayAlias(AA, MI, false);
+    });
+
+  bool SawStore = false;
+  bool HasAliasedStore = false;
+  DenseSet<MachineBasicBlock *> HandledBlocks;
+  DenseSet<MachineBasicBlock *> HandledDomBlocks;
+  // Go through all reachable blocks from From.
+  for (MachineBasicBlock *BB : depth_first(From)) {
+    // We insert the instruction at the start of block To, so no need to worry
+    // about stores inside To.
+    // Store in block From should be already considered when just enter function
+    // SinkInstruction.
+    if (BB == To || BB == From)
+      continue;
+
+    // We already handle this BB in previous iteration.
+    if (HandledBlocks.count(BB))
+      continue;
+
+    HandledBlocks.insert(BB);
+    // To post dominates BB, it must be a path from block From.
+    if (PDT->dominates(To, BB)) {
+      if (!HandledDomBlocks.count(BB))
+        HandledDomBlocks.insert(BB);
+
+      // If this BB is too big or the block number in straight line between From
+      // and To is too big, stop searching to save compiling time.
+      if (BB->size() > SinkLoadInstsPerBlockThreshold ||
+          HandledDomBlocks.size() > SinkLoadBlocksThreshold) {
+        for (auto *DomBB : HandledDomBlocks) {
+          if (DomBB != BB && DT->dominates(DomBB, BB))
+            HasStoreCache[std::make_pair(DomBB, To)] = true;
+          else if(DomBB != BB && DT->dominates(BB, DomBB))
+            HasStoreCache[std::make_pair(From, DomBB)] = true;
+        }
+        HasStoreCache[BlockPair] = true;
+        return true;
+      }
+
+      for (MachineInstr &I : *BB) {
+        // Treat as alias conservatively for a call or an ordered memory
+        // operation.
+        if (I.isCall() || I.hasOrderedMemoryRef()) {
+          for (auto *DomBB : HandledDomBlocks) {
+            if (DomBB != BB && DT->dominates(DomBB, BB))
+              HasStoreCache[std::make_pair(DomBB, To)] = true;
+            else if(DomBB != BB && DT->dominates(BB, DomBB))
+              HasStoreCache[std::make_pair(From, DomBB)] = true;
+          }
+          HasStoreCache[BlockPair] = true;
+          return true;
+        }
+
+        if (I.mayStore()) {
+          SawStore = true;
+          // We still have chance to sink MI if all stores between are not
+          // aliased to MI.
+          // Cache all store instructions, so that we don't need to go through
+          // all From reachable blocks for next load instruction.
+          if (I.mayAlias(AA, MI, false))
+            HasAliasedStore = true;
+          StoreInstrCache[BlockPair].push_back(&I);
+        }
+      }
+    }
+  }
+  // If there is no store at all, cache the result.
+  if (!SawStore)
+    HasStoreCache[BlockPair] = false;
+  return HasAliasedStore;
+}
+
 /// SinkInstruction - Determine whether it is safe to sink the specified machine
 /// instruction out of its current block into a successor.
 bool MachineSinking::SinkInstruction(MachineInstr &MI, bool &SawStore,
@@ -936,8 +1158,9 @@ bool MachineSinking::SinkInstruction(MachineInstr &MI, bool &SawStore,
     // We cannot sink a load across a critical edge - there may be stores in
     // other code paths.
     bool TryBreak = false;
-    bool store = true;
-    if (!MI.isSafeToMove(AA, store)) {
+    bool Store =
+        MI.mayLoad() ? hasStoreBetween(ParentBlock, SuccToSinkTo, MI) : true;
+    if (!MI.isSafeToMove(AA, Store)) {
       LLVM_DEBUG(dbgs() << " *** NOTE: Won't sink load along critical edge.\n");
       TryBreak = true;
     }
@@ -1268,9 +1491,9 @@ static bool hasRegisterDependency(MachineInstr *MI,
   return HasRegDependency;
 }
 
-static SmallSet<unsigned, 4> getRegUnits(unsigned Reg,
-                                         const TargetRegisterInfo *TRI) {
-  SmallSet<unsigned, 4> RegUnits;
+static SmallSet<MCRegister, 4> getRegUnits(MCRegister Reg,
+                                           const TargetRegisterInfo *TRI) {
+  SmallSet<MCRegister, 4> RegUnits;
   for (auto RI = MCRegUnitIterator(Reg, TRI); RI.isValid(); ++RI)
     RegUnits.insert(*RI);
   return RegUnits;
@@ -1320,8 +1543,8 @@ bool PostRAMachineSinking::tryToSinkCopy(MachineBasicBlock &CurBB,
           continue;
 
         // Record debug use of each reg unit.
-        SmallSet<unsigned, 4> Units = getRegUnits(MO.getReg(), TRI);
-        for (unsigned Reg : Units)
+        SmallSet<MCRegister, 4> Units = getRegUnits(MO.getReg(), TRI);
+        for (MCRegister Reg : Units)
           SeenDbgInstrs[Reg].push_back(MI);
       }
       continue;
@@ -1365,18 +1588,17 @@ bool PostRAMachineSinking::tryToSinkCopy(MachineBasicBlock &CurBB,
     // recorded which reg units that DBG_VALUEs read, if this instruction
     // writes any of those units then the corresponding DBG_VALUEs must sink.
     SetVector<MachineInstr *> DbgValsToSinkSet;
-    SmallVector<MachineInstr *, 4> DbgValsToSink;
     for (auto &MO : MI->operands()) {
       if (!MO.isReg() || !MO.isDef())
         continue;
 
-      SmallSet<unsigned, 4> Units = getRegUnits(MO.getReg(), TRI);
-      for (unsigned Reg : Units)
+      SmallSet<MCRegister, 4> Units = getRegUnits(MO.getReg(), TRI);
+      for (MCRegister Reg : Units)
         for (auto *MI : SeenDbgInstrs.lookup(Reg))
           DbgValsToSinkSet.insert(MI);
     }
-    DbgValsToSink.insert(DbgValsToSink.begin(), DbgValsToSinkSet.begin(),
-                         DbgValsToSinkSet.end());
+    SmallVector<MachineInstr *, 4> DbgValsToSink(DbgValsToSinkSet.begin(),
+                                                 DbgValsToSinkSet.end());
 
     // Clear the kill flag if SrcReg is killed between MI and the end of the
     // block.