Remove LLVM 8.0.1 files.

1 files changed, 0 insertions, 827 deletions

diff --git a/gnu/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp b/gnu/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp
deleted file mode 100644
index f8f5f4040c8..00000000000
--- a/gnu/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp
+++ /dev/null
@@ -1,827 +0,0 @@
-//===-- WebAssemblyCFGStackify.cpp - CFG Stackification -------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-///
-/// \file
-/// This file implements a CFG stacking pass.
-///
-/// This pass inserts BLOCK, LOOP, and TRY markers to mark the start of scopes,
-/// since scope boundaries serve as the labels for WebAssembly's control
-/// transfers.
-///
-/// This is sufficient to convert arbitrary CFGs into a form that works on
-/// WebAssembly, provided that all loops are single-entry.
-///
-/// In case we use exceptions, this pass also fixes mismatches in unwind
-/// destinations created during transforming CFG into wasm structured format.
-///
-//===----------------------------------------------------------------------===//
-
-#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
-#include "WebAssembly.h"
-#include "WebAssemblyExceptionInfo.h"
-#include "WebAssemblyMachineFunctionInfo.h"
-#include "WebAssemblySubtarget.h"
-#include "WebAssemblyUtilities.h"
-#include "llvm/CodeGen/MachineDominators.h"
-#include "llvm/CodeGen/MachineFunction.h"
-#include "llvm/CodeGen/MachineInstrBuilder.h"
-#include "llvm/CodeGen/MachineLoopInfo.h"
-#include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/CodeGen/Passes.h"
-#include "llvm/CodeGen/WasmEHFuncInfo.h"
-#include "llvm/MC/MCAsmInfo.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/raw_ostream.h"
-using namespace llvm;
-
-#define DEBUG_TYPE "wasm-cfg-stackify"
-
-namespace {
-class WebAssemblyCFGStackify final : public MachineFunctionPass {
-  StringRef getPassName() const override { return "WebAssembly CFG Stackify"; }
-
-  void getAnalysisUsage(AnalysisUsage &AU) const override {
-    AU.addRequired<MachineDominatorTree>();
-    AU.addRequired<MachineLoopInfo>();
-    AU.addRequired<WebAssemblyExceptionInfo>();
-    MachineFunctionPass::getAnalysisUsage(AU);
-  }
-
-  bool runOnMachineFunction(MachineFunction &MF) override;
-
-  // For each block whose label represents the end of a scope, record the block
-  // which holds the beginning of the scope. This will allow us to quickly skip
-  // over scoped regions when walking blocks.
-  SmallVector<MachineBasicBlock *, 8> ScopeTops;
-
-  void placeMarkers(MachineFunction &MF);
-  void placeBlockMarker(MachineBasicBlock &MBB);
-  void placeLoopMarker(MachineBasicBlock &MBB);
-  void placeTryMarker(MachineBasicBlock &MBB);
-  void rewriteDepthImmediates(MachineFunction &MF);
-  void fixEndsAtEndOfFunction(MachineFunction &MF);
-
-  // For each BLOCK|LOOP|TRY, the corresponding END_(BLOCK|LOOP|TRY).
-  DenseMap<const MachineInstr *, MachineInstr *> BeginToEnd;
-  // For each END_(BLOCK|LOOP|TRY), the corresponding BLOCK|LOOP|TRY.
-  DenseMap<const MachineInstr *, MachineInstr *> EndToBegin;
-  // <TRY marker, EH pad> map
-  DenseMap<const MachineInstr *, MachineBasicBlock *> TryToEHPad;
-  // <EH pad, TRY marker> map
-  DenseMap<const MachineBasicBlock *, MachineInstr *> EHPadToTry;
-  // <LOOP|TRY marker, Loop/exception bottom BB> map
-  DenseMap<const MachineInstr *, MachineBasicBlock *> BeginToBottom;
-
-  // Helper functions to register scope information created by marker
-  // instructions.
-  void registerScope(MachineInstr *Begin, MachineInstr *End);
-  void registerTryScope(MachineInstr *Begin, MachineInstr *End,
-                        MachineBasicBlock *EHPad);
-
-  MachineBasicBlock *getBottom(const MachineInstr *Begin);
-
-public:
-  static char ID; // Pass identification, replacement for typeid
-  WebAssemblyCFGStackify() : MachineFunctionPass(ID) {}
-  ~WebAssemblyCFGStackify() override { releaseMemory(); }
-  void releaseMemory() override;
-};
-} // end anonymous namespace
-
-char WebAssemblyCFGStackify::ID = 0;
-INITIALIZE_PASS(WebAssemblyCFGStackify, DEBUG_TYPE,
-                "Insert BLOCK and LOOP markers for WebAssembly scopes", false,
-                false)
-
-FunctionPass *llvm::createWebAssemblyCFGStackify() {
-  return new WebAssemblyCFGStackify();
-}
-
-/// Test whether Pred has any terminators explicitly branching to MBB, as
-/// opposed to falling through. Note that it's possible (eg. in unoptimized
-/// code) for a branch instruction to both branch to a block and fallthrough
-/// to it, so we check the actual branch operands to see if there are any
-/// explicit mentions.
-static bool ExplicitlyBranchesTo(MachineBasicBlock *Pred,
-                                 MachineBasicBlock *MBB) {
-  for (MachineInstr &MI : Pred->terminators())
-    // Even if a rethrow takes a BB argument, it is not a branch
-    if (!WebAssembly::isRethrow(MI))
-      for (MachineOperand &MO : MI.explicit_operands())
-        if (MO.isMBB() && MO.getMBB() == MBB)
-          return true;
-  return false;
-}
-
-// Returns an iterator to the earliest position possible within the MBB,
-// satisfying the restrictions given by BeforeSet and AfterSet. BeforeSet
-// contains instructions that should go before the marker, and AfterSet contains
-// ones that should go after the marker. In this function, AfterSet is only
-// used for sanity checking.
-static MachineBasicBlock::iterator
-GetEarliestInsertPos(MachineBasicBlock *MBB,
-                     const SmallPtrSet<const MachineInstr *, 4> &BeforeSet,
-                     const SmallPtrSet<const MachineInstr *, 4> &AfterSet) {
-  auto InsertPos = MBB->end();
-  while (InsertPos != MBB->begin()) {
-    if (BeforeSet.count(&*std::prev(InsertPos))) {
-#ifndef NDEBUG
-      // Sanity check
-      for (auto Pos = InsertPos, E = MBB->begin(); Pos != E; --Pos)
-        assert(!AfterSet.count(&*std::prev(Pos)));
-#endif
-      break;
-    }
-    --InsertPos;
-  }
-  return InsertPos;
-}
-
-// Returns an iterator to the latest position possible within the MBB,
-// satisfying the restrictions given by BeforeSet and AfterSet. BeforeSet
-// contains instructions that should go before the marker, and AfterSet contains
-// ones that should go after the marker. In this function, BeforeSet is only
-// used for sanity checking.
-static MachineBasicBlock::iterator
-GetLatestInsertPos(MachineBasicBlock *MBB,
-                   const SmallPtrSet<const MachineInstr *, 4> &BeforeSet,
-                   const SmallPtrSet<const MachineInstr *, 4> &AfterSet) {
-  auto InsertPos = MBB->begin();
-  while (InsertPos != MBB->end()) {
-    if (AfterSet.count(&*InsertPos)) {
-#ifndef NDEBUG
-      // Sanity check
-      for (auto Pos = InsertPos, E = MBB->end(); Pos != E; ++Pos)
-        assert(!BeforeSet.count(&*Pos));
-#endif
-      break;
-    }
-    ++InsertPos;
-  }
-  return InsertPos;
-}
-
-void WebAssemblyCFGStackify::registerScope(MachineInstr *Begin,
-                                           MachineInstr *End) {
-  BeginToEnd[Begin] = End;
-  EndToBegin[End] = Begin;
-}
-
-void WebAssemblyCFGStackify::registerTryScope(MachineInstr *Begin,
-                                              MachineInstr *End,
-                                              MachineBasicBlock *EHPad) {
-  registerScope(Begin, End);
-  TryToEHPad[Begin] = EHPad;
-  EHPadToTry[EHPad] = Begin;
-}
-
-// Given a LOOP/TRY marker, returns its bottom BB. Use cached information if any
-// to prevent recomputation.
-MachineBasicBlock *
-WebAssemblyCFGStackify::getBottom(const MachineInstr *Begin) {
-  const auto &MLI = getAnalysis<MachineLoopInfo>();
-  const auto &WEI = getAnalysis<WebAssemblyExceptionInfo>();
-  if (BeginToBottom.count(Begin))
-    return BeginToBottom[Begin];
-  if (Begin->getOpcode() == WebAssembly::LOOP) {
-    MachineLoop *L = MLI.getLoopFor(Begin->getParent());
-    assert(L);
-    BeginToBottom[Begin] = WebAssembly::getBottom(L);
-  } else if (Begin->getOpcode() == WebAssembly::TRY) {
-    WebAssemblyException *WE = WEI.getExceptionFor(TryToEHPad[Begin]);
-    assert(WE);
-    BeginToBottom[Begin] = WebAssembly::getBottom(WE);
-  } else
-    assert(false);
-  return BeginToBottom[Begin];
-}
-
-/// Insert a BLOCK marker for branches to MBB (if needed).
-void WebAssemblyCFGStackify::placeBlockMarker(MachineBasicBlock &MBB) {
-  // This should have been handled in placeTryMarker.
-  if (MBB.isEHPad())
-    return;
-
-  MachineFunction &MF = *MBB.getParent();
-  auto &MDT = getAnalysis<MachineDominatorTree>();
-  const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
-  const auto &MFI = *MF.getInfo<WebAssemblyFunctionInfo>();
-
-  // First compute the nearest common dominator of all forward non-fallthrough
-  // predecessors so that we minimize the time that the BLOCK is on the stack,
-  // which reduces overall stack height.
-  MachineBasicBlock *Header = nullptr;
-  bool IsBranchedTo = false;
-  int MBBNumber = MBB.getNumber();
-  for (MachineBasicBlock *Pred : MBB.predecessors()) {
-    if (Pred->getNumber() < MBBNumber) {
-      Header = Header ? MDT.findNearestCommonDominator(Header, Pred) : Pred;
-      if (ExplicitlyBranchesTo(Pred, &MBB))
-        IsBranchedTo = true;
-    }
-  }
-  if (!Header)
-    return;
-  if (!IsBranchedTo)
-    return;
-
-  assert(&MBB != &MF.front() && "Header blocks shouldn't have predecessors");
-  MachineBasicBlock *LayoutPred = &*std::prev(MachineFunction::iterator(&MBB));
-
-  // If the nearest common dominator is inside a more deeply nested context,
-  // walk out to the nearest scope which isn't more deeply nested.
-  for (MachineFunction::iterator I(LayoutPred), E(Header); I != E; --I) {
-    if (MachineBasicBlock *ScopeTop = ScopeTops[I->getNumber()]) {
-      if (ScopeTop->getNumber() > Header->getNumber()) {
-        // Skip over an intervening scope.
-        I = std::next(MachineFunction::iterator(ScopeTop));
-      } else {
-        // We found a scope level at an appropriate depth.
-        Header = ScopeTop;
-        break;
-      }
-    }
-  }
-
-  // Decide where in Header to put the BLOCK.
-
-  // Instructions that should go before the BLOCK.
-  SmallPtrSet<const MachineInstr *, 4> BeforeSet;
-  // Instructions that should go after the BLOCK.
-  SmallPtrSet<const MachineInstr *, 4> AfterSet;
-  for (const auto &MI : *Header) {
-    // If there is a previously placed LOOP/TRY marker and the bottom block of
-    // the loop/exception is above MBB, it should be after the BLOCK, because
-    // the loop/exception is nested in this block. Otherwise it should be before
-    // the BLOCK.
-    if (MI.getOpcode() == WebAssembly::LOOP ||
-        MI.getOpcode() == WebAssembly::TRY) {
-      if (MBB.getNumber() > getBottom(&MI)->getNumber())
-        AfterSet.insert(&MI);
-#ifndef NDEBUG
-      else
-        BeforeSet.insert(&MI);
-#endif
-    }
-
-    // All previously inserted BLOCK markers should be after the BLOCK because
-    // they are all nested blocks.
-    if (MI.getOpcode() == WebAssembly::BLOCK)
-      AfterSet.insert(&MI);
-
-#ifndef NDEBUG
-    // All END_(BLOCK|LOOP|TRY) markers should be before the BLOCK.
-    if (MI.getOpcode() == WebAssembly::END_BLOCK ||
-        MI.getOpcode() == WebAssembly::END_LOOP ||
-        MI.getOpcode() == WebAssembly::END_TRY)
-      BeforeSet.insert(&MI);
-#endif
-
-    // Terminators should go after the BLOCK.
-    if (MI.isTerminator())
-      AfterSet.insert(&MI);
-  }
-
-  // Local expression tree should go after the BLOCK.
-  for (auto I = Header->getFirstTerminator(), E = Header->begin(); I != E;
-       --I) {
-    if (std::prev(I)->isDebugInstr() || std::prev(I)->isPosition())
-      continue;
-    if (WebAssembly::isChild(*std::prev(I), MFI))
-      AfterSet.insert(&*std::prev(I));
-    else
-      break;
-  }
-
-  // Add the BLOCK.
-  auto InsertPos = GetLatestInsertPos(Header, BeforeSet, AfterSet);
-  MachineInstr *Begin =
-      BuildMI(*Header, InsertPos, Header->findDebugLoc(InsertPos),
-              TII.get(WebAssembly::BLOCK))
-          .addImm(int64_t(WebAssembly::ExprType::Void));
-
-  // Decide where in Header to put the END_BLOCK.
-  BeforeSet.clear();
-  AfterSet.clear();
-  for (auto &MI : MBB) {
-#ifndef NDEBUG
-    // END_BLOCK should precede existing LOOP and TRY markers.
-    if (MI.getOpcode() == WebAssembly::LOOP ||
-        MI.getOpcode() == WebAssembly::TRY)
-      AfterSet.insert(&MI);
-#endif
-
-    // If there is a previously placed END_LOOP marker and the header of the
-    // loop is above this block's header, the END_LOOP should be placed after
-    // the BLOCK, because the loop contains this block. Otherwise the END_LOOP
-    // should be placed before the BLOCK. The same for END_TRY.
-    if (MI.getOpcode() == WebAssembly::END_LOOP ||
-        MI.getOpcode() == WebAssembly::END_TRY) {
-      if (EndToBegin[&MI]->getParent()->getNumber() >= Header->getNumber())
-        BeforeSet.insert(&MI);
-#ifndef NDEBUG
-      else
-        AfterSet.insert(&MI);
-#endif
-    }
-  }
-
-  // Mark the end of the block.
-  InsertPos = GetEarliestInsertPos(&MBB, BeforeSet, AfterSet);
-  MachineInstr *End = BuildMI(MBB, InsertPos, MBB.findPrevDebugLoc(InsertPos),
-                              TII.get(WebAssembly::END_BLOCK));
-  registerScope(Begin, End);
-
-  // Track the farthest-spanning scope that ends at this point.
-  int Number = MBB.getNumber();
-  if (!ScopeTops[Number] ||
-      ScopeTops[Number]->getNumber() > Header->getNumber())
-    ScopeTops[Number] = Header;
-}
-
-/// Insert a LOOP marker for a loop starting at MBB (if it's a loop header).
-void WebAssemblyCFGStackify::placeLoopMarker(MachineBasicBlock &MBB) {
-  MachineFunction &MF = *MBB.getParent();
-  const auto &MLI = getAnalysis<MachineLoopInfo>();
-  const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
-
-  MachineLoop *Loop = MLI.getLoopFor(&MBB);
-  if (!Loop || Loop->getHeader() != &MBB)
-    return;
-
-  // The operand of a LOOP is the first block after the loop. If the loop is the
-  // bottom of the function, insert a dummy block at the end.
-  MachineBasicBlock *Bottom = WebAssembly::getBottom(Loop);
-  auto Iter = std::next(MachineFunction::iterator(Bottom));
-  if (Iter == MF.end()) {
-    MachineBasicBlock *Label = MF.CreateMachineBasicBlock();
-    // Give it a fake predecessor so that AsmPrinter prints its label.
-    Label->addSuccessor(Label);
-    MF.push_back(Label);
-    Iter = std::next(MachineFunction::iterator(Bottom));
-  }
-  MachineBasicBlock *AfterLoop = &*Iter;
-
-  // Decide where in Header to put the LOOP.
-  SmallPtrSet<const MachineInstr *, 4> BeforeSet;
-  SmallPtrSet<const MachineInstr *, 4> AfterSet;
-  for (const auto &MI : MBB) {
-    // LOOP marker should be after any existing loop that ends here. Otherwise
-    // we assume the instruction belongs to the loop.
-    if (MI.getOpcode() == WebAssembly::END_LOOP)
-      BeforeSet.insert(&MI);
-#ifndef NDEBUG
-    else
-      AfterSet.insert(&MI);
-#endif
-  }
-
-  // Mark the beginning of the loop.
-  auto InsertPos = GetEarliestInsertPos(&MBB, BeforeSet, AfterSet);
-  MachineInstr *Begin = BuildMI(MBB, InsertPos, MBB.findDebugLoc(InsertPos),
-                                TII.get(WebAssembly::LOOP))
-                            .addImm(int64_t(WebAssembly::ExprType::Void));
-
-  // Decide where in Header to put the END_LOOP.
-  BeforeSet.clear();
-  AfterSet.clear();
-#ifndef NDEBUG
-  for (const auto &MI : MBB)
-    // Existing END_LOOP markers belong to parent loops of this loop
-    if (MI.getOpcode() == WebAssembly::END_LOOP)
-      AfterSet.insert(&MI);
-#endif
-
-  // Mark the end of the loop (using arbitrary debug location that branched to
-  // the loop end as its location).
-  InsertPos = GetEarliestInsertPos(AfterLoop, BeforeSet, AfterSet);
-  DebugLoc EndDL = (*AfterLoop->pred_rbegin())->findBranchDebugLoc();
-  MachineInstr *End =
-      BuildMI(*AfterLoop, InsertPos, EndDL, TII.get(WebAssembly::END_LOOP));
-  registerScope(Begin, End);
-
-  assert((!ScopeTops[AfterLoop->getNumber()] ||
-          ScopeTops[AfterLoop->getNumber()]->getNumber() < MBB.getNumber()) &&
-         "With block sorting the outermost loop for a block should be first.");
-  if (!ScopeTops[AfterLoop->getNumber()])
-    ScopeTops[AfterLoop->getNumber()] = &MBB;
-}
-
-void WebAssemblyCFGStackify::placeTryMarker(MachineBasicBlock &MBB) {
-  if (!MBB.isEHPad())
-    return;
-
-  // catch_all terminate pad is grouped together with catch terminate pad and
-  // does not need a separate TRY and END_TRY marker.
-  if (WebAssembly::isCatchAllTerminatePad(MBB))
-    return;
-
-  MachineFunction &MF = *MBB.getParent();
-  auto &MDT = getAnalysis<MachineDominatorTree>();
-  const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
-  const auto &WEI = getAnalysis<WebAssemblyExceptionInfo>();
-  const auto &MFI = *MF.getInfo<WebAssemblyFunctionInfo>();
-
-  // Compute the nearest common dominator of all unwind predecessors
-  MachineBasicBlock *Header = nullptr;
-  int MBBNumber = MBB.getNumber();
-  for (auto *Pred : MBB.predecessors()) {
-    if (Pred->getNumber() < MBBNumber) {
-      Header = Header ? MDT.findNearestCommonDominator(Header, Pred) : Pred;
-      assert(!ExplicitlyBranchesTo(Pred, &MBB) &&
-             "Explicit branch to an EH pad!");
-    }
-  }
-  if (!Header)
-    return;
-
-  // If this try is at the bottom of the function, insert a dummy block at the
-  // end.
-  WebAssemblyException *WE = WEI.getExceptionFor(&MBB);
-  assert(WE);
-  MachineBasicBlock *Bottom = WebAssembly::getBottom(WE);
-
-  auto Iter = std::next(MachineFunction::iterator(Bottom));
-  if (Iter == MF.end()) {
-    MachineBasicBlock *Label = MF.CreateMachineBasicBlock();
-    // Give it a fake predecessor so that AsmPrinter prints its label.
-    Label->addSuccessor(Label);
-    MF.push_back(Label);
-    Iter = std::next(MachineFunction::iterator(Bottom));
-  }
-  MachineBasicBlock *AfterTry = &*Iter;
-
-  assert(AfterTry != &MF.front());
-  MachineBasicBlock *LayoutPred =
-      &*std::prev(MachineFunction::iterator(AfterTry));
-
-  // If the nearest common dominator is inside a more deeply nested context,
-  // walk out to the nearest scope which isn't more deeply nested.
-  for (MachineFunction::iterator I(LayoutPred), E(Header); I != E; --I) {
-    if (MachineBasicBlock *ScopeTop = ScopeTops[I->getNumber()]) {
-      if (ScopeTop->getNumber() > Header->getNumber()) {
-        // Skip over an intervening scope.
-        I = std::next(MachineFunction::iterator(ScopeTop));
-      } else {
-        // We found a scope level at an appropriate depth.
-        Header = ScopeTop;
-        break;
-      }
-    }
-  }
-
-  // Decide where in Header to put the TRY.
-
-  // Instructions that should go before the BLOCK.
-  SmallPtrSet<const MachineInstr *, 4> BeforeSet;
-  // Instructions that should go after the BLOCK.
-  SmallPtrSet<const MachineInstr *, 4> AfterSet;
-  for (const auto &MI : *Header) {
-    // If there is a previously placed LOOP marker and the bottom block of
-    // the loop is above MBB, the LOOP should be after the TRY, because the
-    // loop is nested in this try. Otherwise it should be before the TRY.
-    if (MI.getOpcode() == WebAssembly::LOOP) {
-      if (MBB.getNumber() > Bottom->getNumber())
-        AfterSet.insert(&MI);
-#ifndef NDEBUG
-      else
-        BeforeSet.insert(&MI);
-#endif
-    }
-
-    // All previously inserted TRY markers should be after the TRY because they
-    // are all nested trys.
-    if (MI.getOpcode() == WebAssembly::TRY)
-      AfterSet.insert(&MI);
-
-#ifndef NDEBUG
-    // All END_(LOOP/TRY) markers should be before the TRY.
-    if (MI.getOpcode() == WebAssembly::END_LOOP ||
-        MI.getOpcode() == WebAssembly::END_TRY)
-      BeforeSet.insert(&MI);
-#endif
-
-    // Terminators should go after the TRY.
-    if (MI.isTerminator())
-      AfterSet.insert(&MI);
-  }
-
-  // Local expression tree should go after the TRY.
-  for (auto I = Header->getFirstTerminator(), E = Header->begin(); I != E;
-       --I) {
-    if (std::prev(I)->isDebugInstr() || std::prev(I)->isPosition())
-      continue;
-    if (WebAssembly::isChild(*std::prev(I), MFI))
-      AfterSet.insert(&*std::prev(I));
-    else
-      break;
-  }
-
-  // If Header unwinds to MBB (= Header contains 'invoke'), the try block should
-  // contain the call within it. So the call should go after the TRY. The
-  // exception is when the header's terminator is a rethrow instruction, in
-  // which case that instruction, not a call instruction before it, is gonna
-  // throw.
-  if (MBB.isPredecessor(Header)) {
-    auto TermPos = Header->getFirstTerminator();
-    if (TermPos == Header->end() || !WebAssembly::isRethrow(*TermPos)) {
-      for (const auto &MI : reverse(*Header)) {
-        if (MI.isCall()) {
-          AfterSet.insert(&MI);
-          break;
-        }
-      }
-    }
-  }
-
-  // Add the TRY.
-  auto InsertPos = GetLatestInsertPos(Header, BeforeSet, AfterSet);
-  MachineInstr *Begin =
-      BuildMI(*Header, InsertPos, Header->findDebugLoc(InsertPos),
-              TII.get(WebAssembly::TRY))
-          .addImm(int64_t(WebAssembly::ExprType::Void));
-
-  // Decide where in Header to put the END_TRY.
-  BeforeSet.clear();
-  AfterSet.clear();
-  for (const auto &MI : *AfterTry) {
-#ifndef NDEBUG
-    // END_TRY should precede existing LOOP markers.
-    if (MI.getOpcode() == WebAssembly::LOOP)
-      AfterSet.insert(&MI);
-
-    // All END_TRY markers placed earlier belong to exceptions that contains
-    // this one.
-    if (MI.getOpcode() == WebAssembly::END_TRY)
-      AfterSet.insert(&MI);
-#endif
-
-    // If there is a previously placed END_LOOP marker and its header is after
-    // where TRY marker is, this loop is contained within the 'catch' part, so
-    // the END_TRY marker should go after that. Otherwise, the whole try-catch
-    // is contained within this loop, so the END_TRY should go before that.
-    if (MI.getOpcode() == WebAssembly::END_LOOP) {
-      if (EndToBegin[&MI]->getParent()->getNumber() >= Header->getNumber())
-        BeforeSet.insert(&MI);
-#ifndef NDEBUG
-      else
-        AfterSet.insert(&MI);
-#endif
-    }
-  }
-
-  // Mark the end of the TRY.
-  InsertPos = GetEarliestInsertPos(AfterTry, BeforeSet, AfterSet);
-  MachineInstr *End =
-      BuildMI(*AfterTry, InsertPos, Bottom->findBranchDebugLoc(),
-              TII.get(WebAssembly::END_TRY));
-  registerTryScope(Begin, End, &MBB);
-
-  // Track the farthest-spanning scope that ends at this point.
-  int Number = AfterTry->getNumber();
-  if (!ScopeTops[Number] ||
-      ScopeTops[Number]->getNumber() > Header->getNumber())
-    ScopeTops[Number] = Header;
-}
-
-static unsigned
-GetDepth(const SmallVectorImpl<const MachineBasicBlock *> &Stack,
-         const MachineBasicBlock *MBB) {
-  unsigned Depth = 0;
-  for (auto X : reverse(Stack)) {
-    if (X == MBB)
-      break;
-    ++Depth;
-  }
-  assert(Depth < Stack.size() && "Branch destination should be in scope");
-  return Depth;
-}
-
-/// In normal assembly languages, when the end of a function is unreachable,
-/// because the function ends in an infinite loop or a noreturn call or similar,
-/// it isn't necessary to worry about the function return type at the end of
-/// the function, because it's never reached. However, in WebAssembly, blocks
-/// that end at the function end need to have a return type signature that
-/// matches the function signature, even though it's unreachable. This function
-/// checks for such cases and fixes up the signatures.
-void WebAssemblyCFGStackify::fixEndsAtEndOfFunction(MachineFunction &MF) {
-  const auto &MFI = *MF.getInfo<WebAssemblyFunctionInfo>();
-  assert(MFI.getResults().size() <= 1);
-
-  if (MFI.getResults().empty())
-    return;
-
-  WebAssembly::ExprType retType;
-  switch (MFI.getResults().front().SimpleTy) {
-  case MVT::i32:
-    retType = WebAssembly::ExprType::I32;
-    break;
-  case MVT::i64:
-    retType = WebAssembly::ExprType::I64;
-    break;
-  case MVT::f32:
-    retType = WebAssembly::ExprType::F32;
-    break;
-  case MVT::f64:
-    retType = WebAssembly::ExprType::F64;
-    break;
-  case MVT::v16i8:
-  case MVT::v8i16:
-  case MVT::v4i32:
-  case MVT::v2i64:
-  case MVT::v4f32:
-  case MVT::v2f64:
-    retType = WebAssembly::ExprType::V128;
-    break;
-  case MVT::ExceptRef:
-    retType = WebAssembly::ExprType::ExceptRef;
-    break;
-  default:
-    llvm_unreachable("unexpected return type");
-  }
-
-  for (MachineBasicBlock &MBB : reverse(MF)) {
-    for (MachineInstr &MI : reverse(MBB)) {
-      if (MI.isPosition() || MI.isDebugInstr())
-        continue;
-      if (MI.getOpcode() == WebAssembly::END_BLOCK) {
-        EndToBegin[&MI]->getOperand(0).setImm(int32_t(retType));
-        continue;
-      }
-      if (MI.getOpcode() == WebAssembly::END_LOOP) {
-        EndToBegin[&MI]->getOperand(0).setImm(int32_t(retType));
-        continue;
-      }
-      // Something other than an `end`. We're done.
-      return;
-    }
-  }
-}
-
-// WebAssembly functions end with an end instruction, as if the function body
-// were a block.
-static void AppendEndToFunction(MachineFunction &MF,
-                                const WebAssemblyInstrInfo &TII) {
-  BuildMI(MF.back(), MF.back().end(),
-          MF.back().findPrevDebugLoc(MF.back().end()),
-          TII.get(WebAssembly::END_FUNCTION));
-}
-
-/// Insert LOOP/TRY/BLOCK markers at appropriate places.
-void WebAssemblyCFGStackify::placeMarkers(MachineFunction &MF) {
-  const MCAsmInfo *MCAI = MF.getTarget().getMCAsmInfo();
-  // We allocate one more than the number of blocks in the function to
-  // accommodate for the possible fake block we may insert at the end.
-  ScopeTops.resize(MF.getNumBlockIDs() + 1);
-  // Place the LOOP for MBB if MBB is the header of a loop.
-  for (auto &MBB : MF)
-    placeLoopMarker(MBB);
-  // Place the TRY for MBB if MBB is the EH pad of an exception.
-  if (MCAI->getExceptionHandlingType() == ExceptionHandling::Wasm &&
-      MF.getFunction().hasPersonalityFn())
-    for (auto &MBB : MF)
-      placeTryMarker(MBB);
-  // Place the BLOCK for MBB if MBB is branched to from above.
-  for (auto &MBB : MF)
-    placeBlockMarker(MBB);
-}
-
-void WebAssemblyCFGStackify::rewriteDepthImmediates(MachineFunction &MF) {
-  const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
-  // Now rewrite references to basic blocks to be depth immediates.
-  // We need two stacks: one for normal scopes and the other for EH pad scopes.
-  // EH pad stack is used to rewrite depths in rethrow instructions.
-  SmallVector<const MachineBasicBlock *, 8> Stack;
-  SmallVector<const MachineBasicBlock *, 8> EHPadStack;
-  for (auto &MBB : reverse(MF)) {
-    for (auto I = MBB.rbegin(), E = MBB.rend(); I != E; ++I) {
-      MachineInstr &MI = *I;
-      switch (MI.getOpcode()) {
-      case WebAssembly::BLOCK:
-        assert(ScopeTops[Stack.back()->getNumber()]->getNumber() <=
-                   MBB.getNumber() &&
-               "Block/try should be balanced");
-        Stack.pop_back();
-        break;
-
-      case WebAssembly::TRY:
-        assert(ScopeTops[Stack.back()->getNumber()]->getNumber() <=
-                   MBB.getNumber() &&
-               "Block/try marker should be balanced");
-        Stack.pop_back();
-        EHPadStack.pop_back();
-        break;
-
-      case WebAssembly::CATCH_I32:
-      case WebAssembly::CATCH_I64:
-      case WebAssembly::CATCH_ALL:
-        // Currently the only case there are more than one catch for a try is
-        // for catch terminate pad, in the form of
-        //   try
-        //   catch
-        //     call @__clang_call_terminate
-        //     unreachable
-        //   catch_all
-        //     call @std::terminate
-        //     unreachable
-        //   end
-        // So we shouldn't push the current BB for the second catch_all block
-        // here.
-        if (!WebAssembly::isCatchAllTerminatePad(MBB))
-          EHPadStack.push_back(&MBB);
-        break;
-
-      case WebAssembly::LOOP:
-        assert(Stack.back() == &MBB && "Loop top should be balanced");
-        Stack.pop_back();
-        break;
-
-      case WebAssembly::END_BLOCK:
-      case WebAssembly::END_TRY:
-        Stack.push_back(&MBB);
-        break;
-
-      case WebAssembly::END_LOOP:
-        Stack.push_back(EndToBegin[&MI]->getParent());
-        break;
-
-      case WebAssembly::RETHROW: {
-        // Rewrite MBB operands to be depth immediates.
-        unsigned EHPadDepth = GetDepth(EHPadStack, MI.getOperand(0).getMBB());
-        MI.RemoveOperand(0);
-        MI.addOperand(MF, MachineOperand::CreateImm(EHPadDepth));
-        break;
-      }
-
-      case WebAssembly::RETHROW_TO_CALLER: {
-        MachineInstr *Rethrow =
-            BuildMI(MBB, MI, MI.getDebugLoc(), TII.get(WebAssembly::RETHROW))
-                .addImm(EHPadStack.size());
-        MI.eraseFromParent();
-        I = MachineBasicBlock::reverse_iterator(Rethrow);
-        break;
-      }
-
-      default:
-        if (MI.isTerminator()) {
-          // Rewrite MBB operands to be depth immediates.
-          SmallVector<MachineOperand, 4> Ops(MI.operands());
-          while (MI.getNumOperands() > 0)
-            MI.RemoveOperand(MI.getNumOperands() - 1);
-          for (auto MO : Ops) {
-            if (MO.isMBB())
-              MO = MachineOperand::CreateImm(GetDepth(Stack, MO.getMBB()));
-            MI.addOperand(MF, MO);
-          }
-        }
-        break;
-      }
-    }
-  }
-  assert(Stack.empty() && "Control flow should be balanced");
-}
-
-void WebAssemblyCFGStackify::releaseMemory() {
-  ScopeTops.clear();
-  BeginToEnd.clear();
-  EndToBegin.clear();
-  TryToEHPad.clear();
-  EHPadToTry.clear();
-  BeginToBottom.clear();
-}
-
-bool WebAssemblyCFGStackify::runOnMachineFunction(MachineFunction &MF) {
-  LLVM_DEBUG(dbgs() << "********** CFG Stackifying **********\n"
-                       "********** Function: "
-                    << MF.getName() << '\n');
-
-  releaseMemory();
-
-  // Liveness is not tracked for VALUE_STACK physreg.
-  MF.getRegInfo().invalidateLiveness();
-
-  // Place the BLOCK/LOOP/TRY markers to indicate the beginnings of scopes.
-  placeMarkers(MF);
-
-  // Convert MBB operands in terminators to relative depth immediates.
-  rewriteDepthImmediates(MF);
-
-  // Fix up block/loop/try signatures at the end of the function to conform to
-  // WebAssembly's rules.
-  fixEndsAtEndOfFunction(MF);
-
-  // Add an end instruction at the end of the function body.
-  const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
-  if (!MF.getSubtarget<WebAssemblySubtarget>()
-           .getTargetTriple()
-           .isOSBinFormatELF())
-    AppendEndToFunction(MF, TII);
-
-  return true;
-}