Remove exception handling support from the old JIT.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181354 91177308-0d34-0410-b5e6-96231b3b80d8

14 files changed, 5 insertions, 836 deletions

diff --git a/docs/ReleaseNotes_34.rst b/docs/ReleaseNotes_34.rst
index 8b5624e..7decad0 100644
--- a/docs/ReleaseNotes_34.rst
+++ b/docs/ReleaseNotes_34.rst
@@ -41,6 +41,9 @@ Non-comprehensive list of changes in this release
    functionality, or simply have a lot to talk about), see the `NOTE` below
    for adding a new subsection.
 
+* Support for exception handling has been removed from the old JIT. Use MCJIT
+  if you need EH support.
+
 * ... next change ...
 
 .. NOTE
diff --git a/examples/ExceptionDemo/ExceptionDemo.cpp b/examples/ExceptionDemo/ExceptionDemo.cpp
index f9498a5..cf39ea7 100644
--- a/examples/ExceptionDemo/ExceptionDemo.cpp
+++ b/examples/ExceptionDemo/ExceptionDemo.cpp
@@ -1950,7 +1950,6 @@ int main(int argc, char *argv[]) {
 
   // If not set, exception handling will not be turned on
   llvm::TargetOptions Opts;
-  Opts.JITExceptionHandling = true;
 
   llvm::InitializeNativeTarget();
   llvm::InitializeNativeTargetAsmPrinter();
diff --git a/include/llvm/ExecutionEngine/JITMemoryManager.h b/include/llvm/ExecutionEngine/JITMemoryManager.h
index 714a980..b22d899 100644
--- a/include/llvm/ExecutionEngine/JITMemoryManager.h
+++ b/include/llvm/ExecutionEngine/JITMemoryManager.h
@@ -115,22 +115,6 @@ public:
   /// emitting a function.
   virtual void deallocateFunctionBody(void *Body) = 0;
 
-  /// startExceptionTable - When we finished JITing the function, if exception
-  /// handling is set, we emit the exception table.
-  virtual uint8_t* startExceptionTable(const Function* F,
-                                       uintptr_t &ActualSize) = 0;
-
-  /// endExceptionTable - This method is called when the JIT is done emitting
-  /// the exception table.
-  virtual void endExceptionTable(const Function *F, uint8_t *TableStart,
-                                 uint8_t *TableEnd, uint8_t* FrameRegister) = 0;
-
-  /// deallocateExceptionTable - Free the specified exception table's memory.
-  /// The argument must be the return value from a call to startExceptionTable()
-  /// that hasn't been deallocated yet.  This is never called when the JIT is
-  /// currently emitting an exception table.
-  virtual void deallocateExceptionTable(void *ET) = 0;
-
   /// CheckInvariants - For testing only.  Return true if all internal
   /// invariants are preserved, or return false and set ErrorStr to a helpful
   /// error message.
diff --git a/include/llvm/ExecutionEngine/SectionMemoryManager.h b/include/llvm/ExecutionEngine/SectionMemoryManager.h
index 84a4e08..07e6832 100644
--- a/include/llvm/ExecutionEngine/SectionMemoryManager.h
+++ b/include/llvm/ExecutionEngine/SectionMemoryManager.h
@@ -156,18 +156,6 @@ public:
   virtual void deallocateFunctionBody(void *Body) {
     llvm_unreachable("Unexpected call!");
   }
-  virtual uint8_t *startExceptionTable(const Function *F,
-                                       uintptr_t &ActualSize) {
-    llvm_unreachable("Unexpected call!");
-    return 0;
-  }
-  virtual void endExceptionTable(const Function *F, uint8_t *TableStart,
-                                 uint8_t *TableEnd, uint8_t *FrameRegister) {
-    llvm_unreachable("Unexpected call!");
-  }
-  virtual void deallocateExceptionTable(void *ET) {
-    llvm_unreachable("Unexpected call!");
-  }
 };
 
 }
diff --git a/include/llvm/Target/TargetOptions.h b/include/llvm/Target/TargetOptions.h
index c763a59..31c4c75 100644
--- a/include/llvm/Target/TargetOptions.h
+++ b/include/llvm/Target/TargetOptions.h
@@ -45,7 +45,7 @@ namespace llvm {
           NoFramePointerElimNonLeaf(false), LessPreciseFPMADOption(false),
           UnsafeFPMath(false), NoInfsFPMath(false),
           NoNaNsFPMath(false), HonorSignDependentRoundingFPMathOption(false),
-          UseSoftFloat(false), NoZerosInBSS(false), JITExceptionHandling(false),
+          UseSoftFloat(false), NoZerosInBSS(false),
           JITEmitDebugInfo(false), JITEmitDebugInfoToDisk(false),
           GuaranteedTailCallOpt(false), DisableTailCalls(false),
           StackAlignmentOverride(0), RealignStack(true), SSPBufferSize(0),
@@ -123,10 +123,6 @@ namespace llvm {
     /// crt*.o compiling).
     unsigned NoZerosInBSS : 1;
 
-    /// JITExceptionHandling - This flag indicates that the JIT should emit
-    /// exception handling information.
-    unsigned JITExceptionHandling : 1;
-
     /// JITEmitDebugInfo - This flag indicates that the JIT should try to emit
     /// debug information and notify a debugger about it.
     unsigned JITEmitDebugInfo : 1;
diff --git a/lib/CodeGen/TargetOptionsImpl.cpp b/lib/CodeGen/TargetOptionsImpl.cpp
index 435a5e7..c9c88c1 100644
--- a/lib/CodeGen/TargetOptionsImpl.cpp
+++ b/lib/CodeGen/TargetOptionsImpl.cpp
@@ -59,7 +59,6 @@ bool TargetOptions::operator==(const TargetOptions &TO) {
     ARE_EQUAL(HonorSignDependentRoundingFPMathOption) &&
     ARE_EQUAL(UseSoftFloat) &&
     ARE_EQUAL(NoZerosInBSS) &&
-    ARE_EQUAL(JITExceptionHandling) &&
     ARE_EQUAL(JITEmitDebugInfo) &&
     ARE_EQUAL(JITEmitDebugInfoToDisk) &&
     ARE_EQUAL(GuaranteedTailCallOpt) &&
diff --git a/lib/ExecutionEngine/JIT/CMakeLists.txt b/lib/ExecutionEngine/JIT/CMakeLists.txt
index 52bb389..e16baed 100644
--- a/lib/ExecutionEngine/JIT/CMakeLists.txt
+++ b/lib/ExecutionEngine/JIT/CMakeLists.txt
@@ -3,7 +3,6 @@ add_definitions(-DENABLE_X86_JIT)
 
 add_llvm_library(LLVMJIT
   JIT.cpp
-  JITDwarfEmitter.cpp
   JITEmitter.cpp
   JITMemoryManager.cpp
   )
diff --git a/lib/ExecutionEngine/JIT/JITDwarfEmitter.cpp b/lib/ExecutionEngine/JIT/JITDwarfEmitter.cpp
deleted file mode 100644
index 35d2b8b..0000000
--- a/lib/ExecutionEngine/JIT/JITDwarfEmitter.cpp
+++ /dev/null
@@ -1,596 +0,0 @@
-//===----- JITDwarfEmitter.cpp - Write dwarf tables into memory -----------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file defines a JITDwarfEmitter object that is used by the JIT to
-// write dwarf tables to memory.
-//
-//===----------------------------------------------------------------------===//
-
-#include "JITDwarfEmitter.h"
-#include "JIT.h"
-#include "llvm/ADT/DenseMap.h"
-#include "llvm/CodeGen/JITCodeEmitter.h"
-#include "llvm/CodeGen/MachineFunction.h"
-#include "llvm/CodeGen/MachineModuleInfo.h"
-#include "llvm/ExecutionEngine/JITMemoryManager.h"
-#include "llvm/IR/DataLayout.h"
-#include "llvm/IR/Function.h"
-#include "llvm/MC/MCAsmInfo.h"
-#include "llvm/MC/MCSymbol.h"
-#include "llvm/MC/MachineLocation.h"
-#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Target/TargetFrameLowering.h"
-#include "llvm/Target/TargetInstrInfo.h"
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetRegisterInfo.h"
-using namespace llvm;
-
-JITDwarfEmitter::JITDwarfEmitter(JIT& theJit) : MMI(0), Jit(theJit) {}
-
-
-unsigned char* JITDwarfEmitter::EmitDwarfTable(MachineFunction& F,
-                                               JITCodeEmitter& jce,
-                                               unsigned char* StartFunction,
-                                               unsigned char* EndFunction,
-                                               unsigned char* &EHFramePtr) {
-  assert(MMI && "MachineModuleInfo not registered!");
-
-  const TargetMachine& TM = F.getTarget();
-  TD = TM.getDataLayout();
-  stackGrowthDirection = TM.getFrameLowering()->getStackGrowthDirection();
-  RI = TM.getRegisterInfo();
-  MAI = TM.getMCAsmInfo();
-  JCE = &jce;
-
-  unsigned char* ExceptionTable = EmitExceptionTable(&F, StartFunction,
-                                                     EndFunction);
-
-  unsigned char* Result = 0;
-
-  const std::vector<const Function *> Personalities = MMI->getPersonalities();
-  EHFramePtr = EmitCommonEHFrame(Personalities[MMI->getPersonalityIndex()]);
-
-  Result = EmitEHFrame(Personalities[MMI->getPersonalityIndex()], EHFramePtr,
-                       StartFunction, EndFunction, ExceptionTable);
-
-  return Result;
-}
-
-
-void
-JITDwarfEmitter::EmitFrameMoves(intptr_t BaseLabelPtr,
-                                const std::vector<MachineMove> &Moves) const {
-  unsigned PointerSize = TD->getPointerSize();
-  int stackGrowth = stackGrowthDirection == TargetFrameLowering::StackGrowsUp ?
-          PointerSize : -PointerSize;
-  MCSymbol *BaseLabel = 0;
-
-  for (unsigned i = 0, N = Moves.size(); i < N; ++i) {
-    const MachineMove &Move = Moves[i];
-    MCSymbol *Label = Move.getLabel();
-
-    // Throw out move if the label is invalid.
-    if (Label && (*JCE->getLabelLocations())[Label] == 0)
-      continue;
-
-    intptr_t LabelPtr = 0;
-    if (Label) LabelPtr = JCE->getLabelAddress(Label);
-
-    const MachineLocation &Dst = Move.getDestination();
-    const MachineLocation &Src = Move.getSource();
-
-    // Advance row if new location.
-    if (BaseLabelPtr && Label && BaseLabel != Label) {
-      JCE->emitByte(dwarf::DW_CFA_advance_loc4);
-      JCE->emitInt32(LabelPtr - BaseLabelPtr);
-
-      BaseLabel = Label;
-      BaseLabelPtr = LabelPtr;
-    }
-
-    // If advancing cfa.
-    if (Dst.isReg() && Dst.getReg() == MachineLocation::VirtualFP) {
-      if (!Src.isReg()) {
-        if (Src.getReg() == MachineLocation::VirtualFP) {
-          JCE->emitByte(dwarf::DW_CFA_def_cfa_offset);
-        } else {
-          JCE->emitByte(dwarf::DW_CFA_def_cfa);
-          JCE->emitULEB128Bytes(RI->getDwarfRegNum(Src.getReg(), true));
-        }
-
-        JCE->emitULEB128Bytes(-Src.getOffset());
-      } else {
-        llvm_unreachable("Machine move not supported yet.");
-      }
-    } else if (Src.isReg() &&
-      Src.getReg() == MachineLocation::VirtualFP) {
-      if (Dst.isReg()) {
-        JCE->emitByte(dwarf::DW_CFA_def_cfa_register);
-        JCE->emitULEB128Bytes(RI->getDwarfRegNum(Dst.getReg(), true));
-      } else {
-        llvm_unreachable("Machine move not supported yet.");
-      }
-    } else {
-      unsigned Reg = RI->getDwarfRegNum(Src.getReg(), true);
-      int Offset = Dst.getOffset() / stackGrowth;
-
-      if (Offset < 0) {
-        JCE->emitByte(dwarf::DW_CFA_offset_extended_sf);
-        JCE->emitULEB128Bytes(Reg);
-        JCE->emitSLEB128Bytes(Offset);
-      } else if (Reg < 64) {
-        JCE->emitByte(dwarf::DW_CFA_offset + Reg);
-        JCE->emitULEB128Bytes(Offset);
-      } else {
-        JCE->emitByte(dwarf::DW_CFA_offset_extended);
-        JCE->emitULEB128Bytes(Reg);
-        JCE->emitULEB128Bytes(Offset);
-      }
-    }
-  }
-}
-
-/// SharedTypeIds - How many leading type ids two landing pads have in common.
-static unsigned SharedTypeIds(const LandingPadInfo *L,
-                              const LandingPadInfo *R) {
-  const std::vector<int> &LIds = L->TypeIds, &RIds = R->TypeIds;
-  unsigned LSize = LIds.size(), RSize = RIds.size();
-  unsigned MinSize = LSize < RSize ? LSize : RSize;
-  unsigned Count = 0;
-
-  for (; Count != MinSize; ++Count)
-    if (LIds[Count] != RIds[Count])
-      return Count;
-
-  return Count;
-}
-
-
-/// PadLT - Order landing pads lexicographically by type id.
-static bool PadLT(const LandingPadInfo *L, const LandingPadInfo *R) {
-  const std::vector<int> &LIds = L->TypeIds, &RIds = R->TypeIds;
-  unsigned LSize = LIds.size(), RSize = RIds.size();
-  unsigned MinSize = LSize < RSize ? LSize : RSize;
-
-  for (unsigned i = 0; i != MinSize; ++i)
-    if (LIds[i] != RIds[i])
-      return LIds[i] < RIds[i];
-
-  return LSize < RSize;
-}
-
-namespace {
-
-/// ActionEntry - Structure describing an entry in the actions table.
-struct ActionEntry {
-  int ValueForTypeID; // The value to write - may not be equal to the type id.
-  int NextAction;
-  struct ActionEntry *Previous;
-};
-
-/// PadRange - Structure holding a try-range and the associated landing pad.
-struct PadRange {
-  // The index of the landing pad.
-  unsigned PadIndex;
-  // The index of the begin and end labels in the landing pad's label lists.
-  unsigned RangeIndex;
-};
-
-typedef DenseMap<MCSymbol*, PadRange> RangeMapType;
-
-/// CallSiteEntry - Structure describing an entry in the call-site table.
-struct CallSiteEntry {
-  MCSymbol *BeginLabel; // zero indicates the start of the function.
-  MCSymbol *EndLabel;   // zero indicates the end of the function.
-  MCSymbol *PadLabel;   // zero indicates that there is no landing pad.
-  unsigned Action;
-};
-
-}
-
-unsigned char* JITDwarfEmitter::EmitExceptionTable(MachineFunction* MF,
-                                         unsigned char* StartFunction,
-                                         unsigned char* EndFunction) const {
-  assert(MMI && "MachineModuleInfo not registered!");
-
-  // Map all labels and get rid of any dead landing pads.
-  MMI->TidyLandingPads(JCE->getLabelLocations());
-
-  const std::vector<const GlobalVariable *> &TypeInfos = MMI->getTypeInfos();
-  const std::vector<unsigned> &FilterIds = MMI->getFilterIds();
-  const std::vector<LandingPadInfo> &PadInfos = MMI->getLandingPads();
-  if (PadInfos.empty()) return 0;
-
-  // Sort the landing pads in order of their type ids.  This is used to fold
-  // duplicate actions.
-  SmallVector<const LandingPadInfo *, 64> LandingPads;
-  LandingPads.reserve(PadInfos.size());
-  for (unsigned i = 0, N = PadInfos.size(); i != N; ++i)
-    LandingPads.push_back(&PadInfos[i]);
-  std::sort(LandingPads.begin(), LandingPads.end(), PadLT);
-
-  // Negative type ids index into FilterIds, positive type ids index into
-  // TypeInfos.  The value written for a positive type id is just the type
-  // id itself.  For a negative type id, however, the value written is the
-  // (negative) byte offset of the corresponding FilterIds entry.  The byte
-  // offset is usually equal to the type id, because the FilterIds entries
-  // are written using a variable width encoding which outputs one byte per
-  // entry as long as the value written is not too large, but can differ.
-  // This kind of complication does not occur for positive type ids because
-  // type infos are output using a fixed width encoding.
-  // FilterOffsets[i] holds the byte offset corresponding to FilterIds[i].
-  SmallVector<int, 16> FilterOffsets;
-  FilterOffsets.reserve(FilterIds.size());
-  int Offset = -1;
-  for(std::vector<unsigned>::const_iterator I = FilterIds.begin(),
-    E = FilterIds.end(); I != E; ++I) {
-    FilterOffsets.push_back(Offset);
-    Offset -= MCAsmInfo::getULEB128Size(*I);
-  }
-
-  // Compute the actions table and gather the first action index for each
-  // landing pad site.
-  SmallVector<ActionEntry, 32> Actions;
-  SmallVector<unsigned, 64> FirstActions;
-  FirstActions.reserve(LandingPads.size());
-
-  int FirstAction = 0;
-  unsigned SizeActions = 0;
-  for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) {
-    const LandingPadInfo *LP = LandingPads[i];
-    const std::vector<int> &TypeIds = LP->TypeIds;
-    const unsigned NumShared = i ? SharedTypeIds(LP, LandingPads[i-1]) : 0;
-    unsigned SizeSiteActions = 0;
-
-    if (NumShared < TypeIds.size()) {
-      unsigned SizeAction = 0;
-      ActionEntry *PrevAction = 0;
-
-      if (NumShared) {
-        const unsigned SizePrevIds = LandingPads[i-1]->TypeIds.size();
-        assert(Actions.size());
-        PrevAction = &Actions.back();
-        SizeAction = MCAsmInfo::getSLEB128Size(PrevAction->NextAction) +
-          MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
-        for (unsigned j = NumShared; j != SizePrevIds; ++j) {
-          SizeAction -= MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
-          SizeAction += -PrevAction->NextAction;
-          PrevAction = PrevAction->Previous;
-        }
-      }
-
-      // Compute the actions.
-      for (unsigned I = NumShared, M = TypeIds.size(); I != M; ++I) {
-        int TypeID = TypeIds[I];
-        assert(-1-TypeID < (int)FilterOffsets.size() && "Unknown filter id!");
-        int ValueForTypeID = TypeID < 0 ? FilterOffsets[-1 - TypeID] : TypeID;
-        unsigned SizeTypeID = MCAsmInfo::getSLEB128Size(ValueForTypeID);
-
-        int NextAction = SizeAction ? -(SizeAction + SizeTypeID) : 0;
-        SizeAction = SizeTypeID + MCAsmInfo::getSLEB128Size(NextAction);
-        SizeSiteActions += SizeAction;
-
-        ActionEntry Action = {ValueForTypeID, NextAction, PrevAction};
-        Actions.push_back(Action);
-
-        PrevAction = &Actions.back();
-      }
-
-      // Record the first action of the landing pad site.
-      FirstAction = SizeActions + SizeSiteActions - SizeAction + 1;
-    } // else identical - re-use previous FirstAction
-
-    FirstActions.push_back(FirstAction);
-
-    // Compute this sites contribution to size.
-    SizeActions += SizeSiteActions;
-  }
-
-  // Compute the call-site table.  Entries must be ordered by address.
-  SmallVector<CallSiteEntry, 64> CallSites;
-
-  RangeMapType PadMap;
-  for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) {
-    const LandingPadInfo *LandingPad = LandingPads[i];
-    for (unsigned j=0, E = LandingPad->BeginLabels.size(); j != E; ++j) {
-      MCSymbol *BeginLabel = LandingPad->BeginLabels[j];
-      assert(!PadMap.count(BeginLabel) && "Duplicate landing pad labels!");
-      PadRange P = { i, j };
-      PadMap[BeginLabel] = P;
-    }
-  }
-
-  bool MayThrow = false;
-  MCSymbol *LastLabel = 0;
-  for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
-        I != E; ++I) {
-    for (MachineBasicBlock::const_iterator MI = I->begin(), E = I->end();
-          MI != E; ++MI) {
-      if (!MI->isLabel()) {
-        MayThrow |= MI->isCall();
-        continue;
-      }
-
-      MCSymbol *BeginLabel = MI->getOperand(0).getMCSymbol();
-      assert(BeginLabel && "Invalid label!");
-
-      if (BeginLabel == LastLabel)
-        MayThrow = false;
-
-      RangeMapType::iterator L = PadMap.find(BeginLabel);
-
-      if (L == PadMap.end())
-        continue;
-
-      PadRange P = L->second;
-      const LandingPadInfo *LandingPad = LandingPads[P.PadIndex];
-
-      assert(BeginLabel == LandingPad->BeginLabels[P.RangeIndex] &&
-              "Inconsistent landing pad map!");
-
-      // If some instruction between the previous try-range and this one may
-      // throw, create a call-site entry with no landing pad for the region
-      // between the try-ranges.
-      if (MayThrow) {
-        CallSiteEntry Site = {LastLabel, BeginLabel, 0, 0};
-        CallSites.push_back(Site);
-      }
-
-      LastLabel = LandingPad->EndLabels[P.RangeIndex];
-      CallSiteEntry Site = {BeginLabel, LastLabel,
-        LandingPad->LandingPadLabel, FirstActions[P.PadIndex]};
-
-      assert(Site.BeginLabel && Site.EndLabel && Site.PadLabel &&
-              "Invalid landing pad!");
-
-      // Try to merge with the previous call-site.
-      if (CallSites.size()) {
-        CallSiteEntry &Prev = CallSites.back();
-        if (Site.PadLabel == Prev.PadLabel && Site.Action == Prev.Action) {
-          // Extend the range of the previous entry.
-          Prev.EndLabel = Site.EndLabel;
-          continue;
-        }
-      }
-
-      // Otherwise, create a new call-site.
-      CallSites.push_back(Site);
-    }
-  }
-  // If some instruction between the previous try-range and the end of the
-  // function may throw, create a call-site entry with no landing pad for the
-  // region following the try-range.
-  if (MayThrow) {
-    CallSiteEntry Site = {LastLabel, 0, 0, 0};
-    CallSites.push_back(Site);
-  }
-
-  // Final tallies.
-  unsigned SizeSites = CallSites.size() * (sizeof(int32_t) + // Site start.
-                                            sizeof(int32_t) + // Site length.
-                                            sizeof(int32_t)); // Landing pad.
-  for (unsigned i = 0, e = CallSites.size(); i < e; ++i)
-    SizeSites += MCAsmInfo::getULEB128Size(CallSites[i].Action);
-
-  unsigned SizeTypes = TypeInfos.size() * TD->getPointerSize();
-
-  unsigned TypeOffset = sizeof(int8_t) + // Call site format
-                        // Call-site table length
-                        MCAsmInfo::getULEB128Size(SizeSites) +
-                        SizeSites + SizeActions + SizeTypes;
-
-  // Begin the exception table.
-  JCE->emitAlignmentWithFill(4, 0);
-  // Asm->EOL("Padding");
-
-  unsigned char* DwarfExceptionTable = (unsigned char*)JCE->getCurrentPCValue();
-
-  // Emit the header.
-  JCE->emitByte(dwarf::DW_EH_PE_omit);
-  // Asm->EOL("LPStart format (DW_EH_PE_omit)");
-  JCE->emitByte(dwarf::DW_EH_PE_absptr);
-  // Asm->EOL("TType format (DW_EH_PE_absptr)");
-  JCE->emitULEB128Bytes(TypeOffset);
-  // Asm->EOL("TType base offset");
-  JCE->emitByte(dwarf::DW_EH_PE_udata4);
-  // Asm->EOL("Call site format (DW_EH_PE_udata4)");
-  JCE->emitULEB128Bytes(SizeSites);
-  // Asm->EOL("Call-site table length");
-
-  // Emit the landing pad site information.
-  for (unsigned i = 0; i < CallSites.size(); ++i) {
-    CallSiteEntry &S = CallSites[i];
-    intptr_t BeginLabelPtr = 0;
-    intptr_t EndLabelPtr = 0;
-
-    if (!S.BeginLabel) {
-      BeginLabelPtr = (intptr_t)StartFunction;
-      JCE->emitInt32(0);
-    } else {
-      BeginLabelPtr = JCE->getLabelAddress(S.BeginLabel);
-      JCE->emitInt32(BeginLabelPtr - (intptr_t)StartFunction);
-    }
-
-    // Asm->EOL("Region start");
-
-    if (!S.EndLabel)
-      EndLabelPtr = (intptr_t)EndFunction;
-    else
-      EndLabelPtr = JCE->getLabelAddress(S.EndLabel);
-
-    JCE->emitInt32(EndLabelPtr - BeginLabelPtr);
-    //Asm->EOL("Region length");
-
-    if (!S.PadLabel) {
-      JCE->emitInt32(0);
-    } else {
-      unsigned PadLabelPtr = JCE->getLabelAddress(S.PadLabel);
-      JCE->emitInt32(PadLabelPtr - (intptr_t)StartFunction);
-    }
-    // Asm->EOL("Landing pad");
-
-    JCE->emitULEB128Bytes(S.Action);
-    // Asm->EOL("Action");
-  }
-
-  // Emit the actions.
-  for (unsigned I = 0, N = Actions.size(); I != N; ++I) {
-    ActionEntry &Action = Actions[I];
-
-    JCE->emitSLEB128Bytes(Action.ValueForTypeID);
-    //Asm->EOL("TypeInfo index");
-    JCE->emitSLEB128Bytes(Action.NextAction);
-    //Asm->EOL("Next action");
-  }
-
-  // Emit the type ids.
-  for (unsigned M = TypeInfos.size(); M; --M) {
-    const GlobalVariable *GV = TypeInfos[M - 1];
-
-    if (GV) {
-      if (TD->getPointerSize() == sizeof(int32_t))
-        JCE->emitInt32((intptr_t)Jit.getOrEmitGlobalVariable(GV));
-      else
-        JCE->emitInt64((intptr_t)Jit.getOrEmitGlobalVariable(GV));
-    } else {
-      if (TD->getPointerSize() == sizeof(int32_t))
-        JCE->emitInt32(0);
-      else
-        JCE->emitInt64(0);
-    }
-    // Asm->EOL("TypeInfo");
-  }
-
-  // Emit the filter typeids.
-  for (unsigned j = 0, M = FilterIds.size(); j < M; ++j) {
-    unsigned TypeID = FilterIds[j];
-    JCE->emitULEB128Bytes(TypeID);
-    //Asm->EOL("Filter TypeInfo index");
-  }
-
-  JCE->emitAlignmentWithFill(4, 0);
-
-  return DwarfExceptionTable;
-}
-
-unsigned char*
-JITDwarfEmitter::EmitCommonEHFrame(const Function* Personality) const {
-  unsigned PointerSize = TD->getPointerSize();
-  int stackGrowth = stackGrowthDirection == TargetFrameLowering::StackGrowsUp ?
-          PointerSize : -PointerSize;
-
-  unsigned char* StartCommonPtr = (unsigned char*)JCE->getCurrentPCValue();
-  // EH Common Frame header
-  JCE->allocateSpace(4, 0);
-  unsigned char* FrameCommonBeginPtr = (unsigned char*)JCE->getCurrentPCValue();
-  JCE->emitInt32((int)0);
-  JCE->emitByte(dwarf::DW_CIE_VERSION);
-  JCE->emitString(Personality ? "zPLR" : "zR");
-  JCE->emitULEB128Bytes(1);
-  JCE->emitSLEB128Bytes(stackGrowth);
-  JCE->emitByte(RI->getDwarfRegNum(RI->getRARegister(), true));
-
-  if (Personality) {
-    // Augmentation Size: 3 small ULEBs of one byte each, and the personality
-    // function which size is PointerSize.
-    JCE->emitULEB128Bytes(3 + PointerSize);
-
-    // We set the encoding of the personality as direct encoding because we use
-    // the function pointer. The encoding is not relative because the current
-    // PC value may be bigger than the personality function pointer.
-    if (PointerSize == 4) {
-      JCE->emitByte(dwarf::DW_EH_PE_sdata4);
-      JCE->emitInt32(((intptr_t)Jit.getPointerToGlobal(Personality)));
-    } else {
-      JCE->emitByte(dwarf::DW_EH_PE_sdata8);
-      JCE->emitInt64(((intptr_t)Jit.getPointerToGlobal(Personality)));
-    }
-
-    // LSDA encoding: This must match the encoding used in EmitEHFrame ()
-    if (PointerSize == 4)
-      JCE->emitULEB128Bytes(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4);
-    else
-      JCE->emitULEB128Bytes(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8);
-    JCE->emitULEB128Bytes(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4);
-  } else {
-    JCE->emitULEB128Bytes(1);
-    JCE->emitULEB128Bytes(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4);
-  }
-
-  EmitFrameMoves(0, MAI->getInitialFrameState());
-
-  JCE->emitAlignmentWithFill(PointerSize, dwarf::DW_CFA_nop);
-
-  JCE->emitInt32At((uintptr_t*)StartCommonPtr,
-                   (uintptr_t)((unsigned char*)JCE->getCurrentPCValue() -
-                               FrameCommonBeginPtr));
-
-  return StartCommonPtr;
-}
-
-
-unsigned char*
-JITDwarfEmitter::EmitEHFrame(const Function* Personality,
-                             unsigned char* StartCommonPtr,
-                             unsigned char* StartFunction,
-                             unsigned char* EndFunction,
-                             unsigned char* ExceptionTable) const {
-  unsigned PointerSize = TD->getPointerSize();
-
-  // EH frame header.
-  unsigned char* StartEHPtr = (unsigned char*)JCE->getCurrentPCValue();
-  JCE->allocateSpace(4, 0);
-  unsigned char* FrameBeginPtr = (unsigned char*)JCE->getCurrentPCValue();
-  // FDE CIE Offset
-  JCE->emitInt32(FrameBeginPtr - StartCommonPtr);
-  JCE->emitInt32(StartFunction - (unsigned char*)JCE->getCurrentPCValue());
-  JCE->emitInt32(EndFunction - StartFunction);
-
-  // If there is a personality and landing pads then point to the language
-  // specific data area in the exception table.
-  if (Personality) {
-    JCE->emitULEB128Bytes(PointerSize == 4 ? 4 : 8);
-
-    if (PointerSize == 4) {
-      if (!MMI->getLandingPads().empty())
-        JCE->emitInt32(ExceptionTable-(unsigned char*)JCE->getCurrentPCValue());
-      else
-        JCE->emitInt32((int)0);
-    } else {
-      if (!MMI->getLandingPads().empty())
-        JCE->emitInt64(ExceptionTable-(unsigned char*)JCE->getCurrentPCValue());
-      else
-        JCE->emitInt64((int)0);
-    }
-  } else {
-    JCE->emitULEB128Bytes(0);
-  }
-
-  // Indicate locations of function specific  callee saved registers in
-  // frame.
-  EmitFrameMoves((intptr_t)StartFunction, MMI->getFrameMoves());
-
-  JCE->emitAlignmentWithFill(PointerSize, dwarf::DW_CFA_nop);
-
-  // Indicate the size of the table
-  JCE->emitInt32At((uintptr_t*)StartEHPtr,
-                   (uintptr_t)((unsigned char*)JCE->getCurrentPCValue() -
-                               StartEHPtr));
-
-  // Double zeroes for the unwind runtime
-  if (PointerSize == 8) {
-    JCE->emitInt64(0);
-    JCE->emitInt64(0);
-  } else {
-    JCE->emitInt32(0);
-    JCE->emitInt32(0);
-  }
-
-  return StartEHPtr;
-}
diff --git a/lib/ExecutionEngine/JIT/JITEmitter.cpp b/lib/ExecutionEngine/JIT/JITEmitter.cpp
index c273876..d813c53 100644
--- a/lib/ExecutionEngine/JIT/JITEmitter.cpp
+++ b/lib/ExecutionEngine/JIT/JITEmitter.cpp
@@ -363,22 +363,16 @@ namespace {
     /// Instance of the JIT
     JIT *TheJIT;
 
-    bool JITExceptionHandling;
-
   public:
     JITEmitter(JIT &jit, JITMemoryManager *JMM, TargetMachine &TM)
       : SizeEstimate(0), Resolver(jit, *this), MMI(0), CurFn(0),
-        EmittedFunctions(this), TheJIT(&jit),
-        JITExceptionHandling(TM.Options.JITExceptionHandling) {
+        EmittedFunctions(this), TheJIT(&jit) {
       MemMgr = JMM ? JMM : JITMemoryManager::CreateDefaultMemManager();
       if (jit.getJITInfo().needsGOT()) {
         MemMgr->AllocateGOT();
         DEBUG(dbgs() << "JIT is managing a GOT\n");
       }
 
-      if (JITExceptionHandling) {
-        DE.reset(new JITDwarfEmitter(jit));
-      }
     }
     ~JITEmitter() {
       delete MemMgr;
@@ -964,40 +958,6 @@ bool JITEmitter::finishFunction(MachineFunction &F) {
       }
     });
 
-  if (JITExceptionHandling) {
-    uintptr_t ActualSize = 0;
-    SavedBufferBegin = BufferBegin;
-    SavedBufferEnd = BufferEnd;
-    SavedCurBufferPtr = CurBufferPtr;
-    uint8_t *FrameRegister;
-
-    while (true) {
-      BufferBegin = CurBufferPtr = MemMgr->startExceptionTable(F.getFunction(),
-                                                               ActualSize);
-      BufferEnd = BufferBegin+ActualSize;
-      EmittedFunctions[F.getFunction()].ExceptionTable = BufferBegin;
-      uint8_t *EhStart;
-      FrameRegister = DE->EmitDwarfTable(F, *this, FnStart, FnEnd, EhStart);
-
-      // If the buffer was large enough to hold the table then we are done.
-      if (CurBufferPtr != BufferEnd)
-        break;
-
-      // Try again with twice as much space.
-      ActualSize = (CurBufferPtr - BufferBegin) * 2;
-      MemMgr->deallocateExceptionTable(BufferBegin);
-    }
-    MemMgr->endExceptionTable(F.getFunction(), BufferBegin, CurBufferPtr,
-                              FrameRegister);
-    BufferBegin = SavedBufferBegin;
-    BufferEnd = SavedBufferEnd;
-    CurBufferPtr = SavedCurBufferPtr;
-
-    if (JITExceptionHandling) {
-      TheJIT->RegisterTable(F.getFunction(), FrameRegister);
-    }
-  }
-
   if (MMI)
     MMI->EndFunction();
 
@@ -1027,15 +987,10 @@ void JITEmitter::deallocateMemForFunction(const Function *F) {
     Emitted = EmittedFunctions.find(F);
   if (Emitted != EmittedFunctions.end()) {
     MemMgr->deallocateFunctionBody(Emitted->second.FunctionBody);
-    MemMgr->deallocateExceptionTable(Emitted->second.ExceptionTable);
     TheJIT->NotifyFreeingMachineCode(Emitted->second.Code);
 
     EmittedFunctions.erase(Emitted);
   }
-
-  if (JITExceptionHandling) {
-    TheJIT->DeregisterTable(F);
-  }
 }
 
 
diff --git a/lib/ExecutionEngine/JIT/JITMemoryManager.cpp b/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
index 66aeb77..bf5680d 100644
--- a/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
+++ b/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
@@ -513,26 +513,6 @@ namespace {
       return false;
     }
 
-    /// startExceptionTable - Use startFunctionBody to allocate memory for the
-    /// function's exception table.
-    uint8_t* startExceptionTable(const Function* F, uintptr_t &ActualSize) {
-      return startFunctionBody(F, ActualSize);
-    }
-
-    /// endExceptionTable - The exception table of F is now allocated,
-    /// and takes the memory in the range [TableStart,TableEnd).
-    void endExceptionTable(const Function *F, uint8_t *TableStart,
-                           uint8_t *TableEnd, uint8_t* FrameRegister) {
-      assert(TableEnd > TableStart);
-      assert(TableStart == (uint8_t *)(CurBlock+1) &&
-             "Mismatched table start/end!");
-
-      uintptr_t BlockSize = TableEnd - (uint8_t *)CurBlock;
-
-      // Release the memory at the end of this block that isn't needed.
-      FreeMemoryList =CurBlock->TrimAllocationToSize(FreeMemoryList, BlockSize);
-    }
-
     uint8_t *getGOTBase() const {
       return GOTBase;
     }
@@ -557,12 +537,6 @@ namespace {
       if (Body) deallocateBlock(Body);
     }
 
-    /// deallocateExceptionTable - Deallocate memory for the specified
-    /// exception table.
-    void deallocateExceptionTable(void *ET) {
-      if (ET) deallocateBlock(ET);
-    }
-
     /// setMemoryWritable - When code generation is in progress,
     /// the code pages may need permissions changed.
     void setMemoryWritable()
diff --git a/tools/lli/RecordingMemoryManager.cpp b/tools/lli/RecordingMemoryManager.cpp
index e4d992d..1fa8176 100644
--- a/tools/lli/RecordingMemoryManager.cpp
+++ b/tools/lli/RecordingMemoryManager.cpp
@@ -98,17 +98,6 @@ uint8_t *RecordingMemoryManager::allocateGlobal(uintptr_t Size, unsigned Alignme
 void RecordingMemoryManager::deallocateFunctionBody(void *Body) {
   llvm_unreachable("Unexpected!");
 }
-uint8_t* RecordingMemoryManager::startExceptionTable(const Function* F, uintptr_t &ActualSize) {
-  llvm_unreachable("Unexpected!");
-  return 0;
-}
-void RecordingMemoryManager::endExceptionTable(const Function *F, uint8_t *TableStart,
-                                               uint8_t *TableEnd, uint8_t* FrameRegister) {
-  llvm_unreachable("Unexpected!");
-}
-void RecordingMemoryManager::deallocateExceptionTable(void *ET) {
-  llvm_unreachable("Unexpected!");
-}
 
 static int jit_noop() {
   return 0;
diff --git a/tools/lli/RecordingMemoryManager.h b/tools/lli/RecordingMemoryManager.h
index 991f535..f3d026f 100644
--- a/tools/lli/RecordingMemoryManager.h
+++ b/tools/lli/RecordingMemoryManager.h
@@ -75,11 +75,6 @@ public:
   uint8_t *allocateSpace(intptr_t Size, unsigned Alignment);
   uint8_t *allocateGlobal(uintptr_t Size, unsigned Alignment);
   void deallocateFunctionBody(void *Body);
-  uint8_t* startExceptionTable(const Function* F, uintptr_t &ActualSize);
-  void endExceptionTable(const Function *F, uint8_t *TableStart,
-                         uint8_t *TableEnd, uint8_t* FrameRegister);
-  void deallocateExceptionTable(void *ET);
-
 };
 
 } // end namespace llvm
diff --git a/tools/lli/lli.cpp b/tools/lli/lli.cpp
index 297763f..1866403 100644
--- a/tools/lli/lli.cpp
+++ b/tools/lli/lli.cpp
@@ -159,11 +159,6 @@ namespace {
                      clEnumValEnd));
 
   cl::opt<bool>
-  EnableJITExceptionHandling("jit-enable-eh",
-    cl::desc("Emit exception handling information"),
-    cl::init(false));
-
-  cl::opt<bool>
   GenerateSoftFloatCalls("soft-float",
     cl::desc("Generate software floating point library calls"),
     cl::init(false));
@@ -381,7 +376,6 @@ int main(int argc, char **argv, char * const *envp) {
 
   // Remote target execution doesn't handle EH or debug registration.
   if (!RemoteMCJIT) {
-    Options.JITExceptionHandling = EnableJITExceptionHandling;
     Options.JITEmitDebugInfo = EmitJitDebugInfo;
     Options.JITEmitDebugInfoToDisk = EmitJitDebugInfoToDisk;
   }
diff --git a/unittests/ExecutionEngine/JIT/JITTest.cpp b/unittests/ExecutionEngine/JIT/JITTest.cpp
index e6f4cb9..cf995aa 100644
--- a/unittests/ExecutionEngine/JIT/JITTest.cpp
+++ b/unittests/ExecutionEngine/JIT/JITTest.cpp
@@ -143,54 +143,6 @@ public:
     deallocateFunctionBodyCalls.push_back(DeallocateFunctionBodyCall(Body));
     Base->deallocateFunctionBody(Body);
   }
-  struct DeallocateExceptionTableCall {
-    DeallocateExceptionTableCall(const void *ET) : ET(ET) {}
-    const void *ET;
-  };
-  std::vector<DeallocateExceptionTableCall> deallocateExceptionTableCalls;
-  virtual void deallocateExceptionTable(void *ET) {
-    deallocateExceptionTableCalls.push_back(DeallocateExceptionTableCall(ET));
-    Base->deallocateExceptionTable(ET);
-  }
-  struct StartExceptionTableCall {
-    StartExceptionTableCall(uint8_t *Result, const Function *F,
-                            uintptr_t ActualSize, uintptr_t ActualSizeResult)
-      : Result(Result), F(F), F_dump(DumpFunction(F)),
-        ActualSize(ActualSize), ActualSizeResult(ActualSizeResult) {}
-    uint8_t *Result;
-    const Function *F;
-    std::string F_dump;
-    uintptr_t ActualSize;
-    uintptr_t ActualSizeResult;
-  };
-  std::vector<StartExceptionTableCall> startExceptionTableCalls;
-  virtual uint8_t *startExceptionTable(const Function *F,
-                                       uintptr_t &ActualSize) {
-    uintptr_t InitialActualSize = ActualSize;
-    uint8_t *Result = Base->startExceptionTable(F, ActualSize);
-    startExceptionTableCalls.push_back(
-      StartExceptionTableCall(Result, F, InitialActualSize, ActualSize));
-    return Result;
-  }
-  struct EndExceptionTableCall {
-    EndExceptionTableCall(const Function *F, uint8_t *TableStart,
-                          uint8_t *TableEnd, uint8_t* FrameRegister)
-      : F(F), F_dump(DumpFunction(F)),
-        TableStart(TableStart), TableEnd(TableEnd),
-        FrameRegister(FrameRegister) {}
-    const Function *F;
-    std::string F_dump;
-    uint8_t *TableStart;
-    uint8_t *TableEnd;
-    uint8_t *FrameRegister;
-  };
-  std::vector<EndExceptionTableCall> endExceptionTableCalls;
-  virtual void endExceptionTable(const Function *F, uint8_t *TableStart,
-                                 uint8_t *TableEnd, uint8_t* FrameRegister) {
-      endExceptionTableCalls.push_back(
-          EndExceptionTableCall(F, TableStart, TableEnd, FrameRegister));
-    return Base->endExceptionTable(F, TableStart, TableEnd, FrameRegister);
-  }
 };
 
 bool LoadAssemblyInto(Module *M, const char *assembly) {
@@ -216,7 +168,6 @@ class JITTest : public testing::Test {
     RJMM->setPoisonMemory(true);
     std::string Error;
     TargetOptions Options;
-    Options.JITExceptionHandling = true;
     TheJIT.reset(EngineBuilder(M).setEngineKind(EngineKind::JIT)
                  .setJITMemoryManager(RJMM)
                  .setErrorStr(&Error)
@@ -302,46 +253,6 @@ TEST(JIT, GlobalInFunction) {
   EXPECT_EQ(3, *GPtr);
 }
 
-// Regression test for a bug.  The JITEmitter wasn't checking to verify that
-// it hadn't run out of space while generating the DWARF exception information
-// for an emitted function.
-
-class ExceptionMemoryManagerMock : public RecordingJITMemoryManager {
- public:
-  virtual uint8_t *startExceptionTable(const Function *F,
-                                       uintptr_t &ActualSize) {
-    // force an insufficient size the first time through.
-    bool ChangeActualSize = false;
-    if (ActualSize == 0)
-      ChangeActualSize = true;;
-    uint8_t *result =
-      RecordingJITMemoryManager::startExceptionTable(F, ActualSize);
-    if (ChangeActualSize)
-      ActualSize = 1;
-    return result;
-  }
-};
-
-class JITExceptionMemoryTest : public JITTest {
- protected:
-  virtual RecordingJITMemoryManager *createMemoryManager() {
-    return new ExceptionMemoryManagerMock;
-  }
-};
-
-TEST_F(JITExceptionMemoryTest, ExceptionTableOverflow) {
-  Function *F = Function::Create(TypeBuilder<void(void), false>::get(Context),
-                                 Function::ExternalLinkage,
-                                 "func1", M);
-  BasicBlock *Block = BasicBlock::Create(Context, "block", F);
-  IRBuilder<> Builder(Block);
-  Builder.CreateRetVoid();
-  TheJIT->getPointerToFunction(F);
-  ASSERT_TRUE(RJMM->startExceptionTableCalls.size() == 2);
-  ASSERT_TRUE(RJMM->deallocateExceptionTableCalls.size() == 1);
-  ASSERT_TRUE(RJMM->endExceptionTableCalls.size() == 1);
-}
-
 int PlusOne(int arg) {
   return arg + 1;
 }
@@ -501,27 +412,6 @@ TEST_F(JITTest, ModuleDeletion) {
   }
   EXPECT_EQ(RJMM->startFunctionBodyCalls.size(),
             RJMM->deallocateFunctionBodyCalls.size());
-
-  SmallPtrSet<const void*, 2> ExceptionTablesDeallocated;
-  unsigned NumTablesDeallocated = 0;
-  for (unsigned i = 0, e = RJMM->deallocateExceptionTableCalls.size();
-       i != e; ++i) {
-    ExceptionTablesDeallocated.insert(
-        RJMM->deallocateExceptionTableCalls[i].ET);
-    if (RJMM->deallocateExceptionTableCalls[i].ET != NULL) {
-        // If JITEmitDebugInfo is off, we'll "deallocate" NULL, which doesn't
-        // appear in startExceptionTableCalls.
-        NumTablesDeallocated++;
-    }
-  }
-  for (unsigned i = 0, e = RJMM->startExceptionTableCalls.size(); i != e; ++i) {
-    EXPECT_TRUE(ExceptionTablesDeallocated.count(
-                  RJMM->startExceptionTableCalls[i].Result))
-      << "Function's exception table leaked: \n"
-      << RJMM->startExceptionTableCalls[i].F_dump;
-  }
-  EXPECT_EQ(RJMM->startExceptionTableCalls.size(),
-            NumTablesDeallocated);
 }
 
 // ARM, MIPS and PPC still emit stubs for calls since the target may be