[LLVMdev] Exception handling in JIT

Evan Cheng evan.cheng at apple.com
Mon Feb 4 14:15:24 PST 2008


Looks sane. Thanks.

Evan

On Feb 1, 2008, at 1:24 AM, Nicolas Geoffray wrote:

> Dear all,
>
> Here's a new patch with Evan's comments (thx Evan!) and some cleanups.
> Now the (duplicated) exception handling code is in a new file:
> lib/ExecutionEngine/JIT/JITDwarfEmitter.
>
> This patch should work on linux/x86 and linux/ppc (tested).
>
> Nicolas
> Index: include/llvm/ExecutionEngine/ExecutionEngine.h
> ===================================================================
> --- include/llvm/ExecutionEngine/ExecutionEngine.h	(revision 46612)
> +++ include/llvm/ExecutionEngine/ExecutionEngine.h	(working copy)
> @@ -85,6 +85,11 @@
>   /// pointer is invoked to create it. If this returns null, the JIT  
> will abort.
>   void* (*LazyFunctionCreator)(const std::string &);
>
> +  /// ExceptionTableRegister - If Exception Handling is set, the  
> JIT will
> +  /// register dwarf tables with this function
> +  typedef void (*EERegisterFn)(void*);
> +  static EERegisterFn ExceptionTableRegister;
> +
> public:
>   /// lock - This lock is protects the ExecutionEngine, JIT,  
> JITResolver and
>   /// JITEmitter classes.  It must be held while changing the  
> internal state of
> @@ -246,6 +251,18 @@
>   void InstallLazyFunctionCreator(void* (*P)(const std::string &)) {
>     LazyFunctionCreator = P;
>   }
> +
> +  /// InstallExceptionTableRegister - The JIT will use the given  
> function
> +  /// to register the exception tables it generates.
> +  static void InstallExceptionTableRegister(void (*F)(void*)) {
> +    ExceptionTableRegister = F;
> +  }
> +
> +  /// RegisterTable - Registers the given pointer as an exception  
> table. It uses
> +  /// the ExceptionTableRegister function.
> +  static void RegisterTable(void* res) {
> +    ExceptionTableRegister(res);
> +  }
>
> protected:
>   explicit ExecutionEngine(ModuleProvider *P);
> Index: include/llvm/ExecutionEngine/JITMemoryManager.h
> ===================================================================
> --- include/llvm/ExecutionEngine/JITMemoryManager.h	(revision 46612)
> +++ include/llvm/ExecutionEngine/JITMemoryManager.h	(working copy)
> @@ -89,6 +89,17 @@
>   /// deallocateMemForFunction - Free JIT memory for the specified  
> function.
>   /// This is never called when the JIT is currently emitting a  
> function.
>   virtual void deallocateMemForFunction(const Function *F) = 0;
> +
> +  /// startExceptionTable - When we finished JITing the function,  
> if exception
> +  /// handling is set, we emit the exception table.
> +  virtual unsigned char* 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, unsigned char  
> *TableStart,
> +                                 unsigned char *TableEnd,
> +                                 unsigned char* FrameRegister) = 0;
> };
>
> } // end namespace llvm.
> Index: include/llvm/CodeGen/MachineCodeEmitter.h
> ===================================================================
> --- include/llvm/CodeGen/MachineCodeEmitter.h	(revision 46612)
> +++ include/llvm/CodeGen/MachineCodeEmitter.h	(working copy)
> @@ -26,6 +26,7 @@
> class MachineConstantPool;
> class MachineJumpTableInfo;
> class MachineFunction;
> +class MachineModuleInfo;
> class MachineRelocation;
> class Value;
> class GlobalValue;
> @@ -136,6 +137,72 @@
>       CurBufferPtr = BufferEnd;
>   }
>
> +
> +  /// emitULEB128Bytes - This callback is invoked when a ULEB128  
> needs to be
> +  /// written to the output stream.
> +  void emitULEB128Bytes(unsigned Value) {
> +    do {
> +      unsigned char Byte = Value & 0x7f;
> +      Value >>= 7;
> +      if (Value) Byte |= 0x80;
> +      emitByte(Byte);
> +    } while (Value);
> +  }
> +
> +  /// emitSLEB128Bytes - This callback is invoked when a SLEB128  
> needs to be
> +  /// written to the output stream.
> +  void emitSLEB128Bytes(int Value) {
> +    int Sign = Value >> (8 * sizeof(Value) - 1);
> +    bool IsMore;
> +
> +    do {
> +      unsigned char Byte = Value & 0x7f;
> +      Value >>= 7;
> +      IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
> +      if (IsMore) Byte |= 0x80;
> +      emitByte(Byte);
> +    } while (IsMore);
> +  }
> +
> +  /// emitString - This callback is invoked when a String needs to be
> +  /// written to the output stream.
> +  void emitString(const std::string &String) {
> +    for (unsigned i = 0, N = String.size(); i < N; ++i) {
> +      unsigned char C = String[i];
> +      emitByte(C);
> +    }
> +    emitByte(0);
> +  }
> +
> +  /// emitInt32 - Emit a int32 directive.
> +  void emitInt32(int Value) {
> +    if (CurBufferPtr+4 <= BufferEnd) {
> +      *((uint32_t*)CurBufferPtr) = Value;
> +      CurBufferPtr += 4;
> +    } else {
> +      CurBufferPtr = BufferEnd;
> +    }
> +  }
> +
> +  /// emitInt64 - Emit a int64 directive.
> +  void emitInt64(uint64_t Value) {
> +    if (CurBufferPtr+8 <= BufferEnd) {
> +      *((uint64_t*)CurBufferPtr) = Value;
> +      CurBufferPtr += 8;
> +    } else {
> +      CurBufferPtr = BufferEnd;
> +    }
> +  }
> +
> +  /// emitAt - Emit Value in Addr
> +  void emitAt(uintptr_t *Addr, uintptr_t Value) {
> +    if (Addr >= (uintptr_t*)BufferBegin && Addr <  
> (uintptr_t*)BufferEnd)
> +      (*Addr) = Value;
> +  }
> +
> +  /// emitLabel - Emits a label
> +  virtual void emitLabel(uint64_t LabelID) = 0;
> +
>   /// allocateSpace - Allocate a block of space in the current  
> output buffer,
>   /// returning null (and setting conditions to indicate buffer  
> overflow) on
>   /// failure.  Alignment is the alignment in bytes of the buffer  
> desired.
> @@ -194,6 +261,15 @@
>   /// emitted.
>   ///
>   virtual intptr_t getMachineBasicBlockAddress(MachineBasicBlock  
> *MBB) const= 0;
> +
> +  /// getLabelAddress - Return the address of the specified  
> LabelID, only usable
> +  /// after the LabelID has been emitted.
> +  ///
> +  virtual intptr_t getLabelAddress(uint64_t LabelID) const = 0;
> +
> +  /// Specifies the MachineModuleInfo object. This is used for  
> exception handling
> +  /// purposes.
> +  virtual void setModuleInfo(MachineModuleInfo* Info) = 0;
> };
>
> } // End llvm namespace
> Index: lib/CodeGen/LLVMTargetMachine.cpp
> ===================================================================
> --- lib/CodeGen/LLVMTargetMachine.cpp	(revision 46612)
> +++ lib/CodeGen/LLVMTargetMachine.cpp	(working copy)
> @@ -186,8 +186,8 @@
>
>   PM.add(createGCLoweringPass());
>
> -  // FIXME: Implement the invoke/unwind instructions!
> -  PM.add(createLowerInvokePass(getTargetLowering()));
> +  if (!ExceptionHandling)
> +    PM.add(createLowerInvokePass(getTargetLowering()));
>
>   // Make sure that no unreachable blocks are instruction selected.
>   PM.add(createUnreachableBlockEliminationPass());
> Index: lib/CodeGen/ELFWriter.cpp
> ===================================================================
> --- lib/CodeGen/ELFWriter.cpp	(revision 46612)
> +++ lib/CodeGen/ELFWriter.cpp	(working copy)
> @@ -98,6 +98,21 @@
>       return 0;
>     }
>
> +    virtual intptr_t getLabelAddress(uint64_t Label) const {
> +      assert(0 && "Label address not implementated yet!");
> +      abort();
> +      return 0;
> +    }
> +
> +    virtual void emitLabel(uint64_t LabelID) {
> +      assert(0 && "emit Label not implementated yet!");
> +      abort();
> +    }
> +
> +
> +    virtual void setModuleInfo(llvm::MachineModuleInfo* MMI) { }
> +
> +
>     /// JIT SPECIFIC FUNCTIONS - DO NOT IMPLEMENT THESE HERE!
>     void startFunctionStub(unsigned StubSize, unsigned Alignment =  
> 1) {
>       assert(0 && "JIT specific function called!");
> Index: lib/CodeGen/MachOWriter.cpp
> ===================================================================
> --- lib/CodeGen/MachOWriter.cpp	(revision 46612)
> +++ lib/CodeGen/MachOWriter.cpp	(working copy)
> @@ -125,6 +125,20 @@
>       return MBBLocations[MBB->getNumber()];
>     }
>
> +    virtual intptr_t getLabelAddress(uint64_t Label) const {
> +      assert(0 && "get Label not implemented");
> +      abort();
> +      return 0;
> +    }
> +
> +    virtual void emitLabel(uint64_t LabelID) {
> +      assert(0 && "emit Label not implemented");
> +      abort();
> +    }
> +
> +
> +    virtual void setModuleInfo(llvm::MachineModuleInfo* MMI) { }
> +
>     /// JIT SPECIFIC FUNCTIONS - DO NOT IMPLEMENT THESE HERE!
>     virtual void startFunctionStub(unsigned StubSize, unsigned  
> Alignment = 1) {
>       assert(0 && "JIT specific function called!");
> Index: lib/Target/PowerPC/PPCCodeEmitter.cpp
> ===================================================================
> --- lib/Target/PowerPC/PPCCodeEmitter.cpp	(revision 46612)
> +++ lib/Target/PowerPC/PPCCodeEmitter.cpp	(working copy)
> @@ -20,6 +20,7 @@
> #include "llvm/CodeGen/MachineCodeEmitter.h"
> #include "llvm/CodeGen/MachineFunctionPass.h"
> #include "llvm/CodeGen/MachineInstrBuilder.h"
> +#include "llvm/CodeGen/MachineModuleInfo.h"
> #include "llvm/CodeGen/Passes.h"
> #include "llvm/Support/Debug.h"
> #include "llvm/Support/Compiler.h"
> @@ -38,6 +39,11 @@
>     /// getMachineOpValue - evaluates the MachineOperand of a given  
> MachineInstr
>     ///
>     int getMachineOpValue(MachineInstr &MI, MachineOperand &MO);
> +
> +    void getAnalysisUsage(AnalysisUsage &AU) const {
> +      AU.addRequired<MachineModuleInfo>();
> +      MachineFunctionPass::getAnalysisUsage(AU);
> +    }
>
>   public:
>     static char ID;
> @@ -82,6 +88,8 @@
>   assert((MF.getTarget().getRelocationModel() != Reloc::Default ||
>           MF.getTarget().getRelocationModel() != Reloc::Static) &&
>          "JIT relocation model must be set to static or default!");
> +
> +  MCE.setModuleInfo(&getAnalysis<MachineModuleInfo>());
>   do {
>     MovePCtoLROffset = 0;
>     MCE.startFunction(MF);
> @@ -101,6 +109,9 @@
>     default:
>       MCE.emitWordBE(getBinaryCodeForInstr(*I));
>       break;
> +    case TargetInstrInfo::LABEL:
> +      MCE.emitLabel(MI.getOperand(0).getImm());
> +      break;
>     case PPC::IMPLICIT_DEF_GPRC:
>     case PPC::IMPLICIT_DEF_G8RC:
>     case PPC::IMPLICIT_DEF_F8:
> Index: lib/Target/X86/X86CodeEmitter.cpp
> ===================================================================
> --- lib/Target/X86/X86CodeEmitter.cpp	(revision 46612)
> +++ lib/Target/X86/X86CodeEmitter.cpp	(working copy)
> @@ -23,6 +23,7 @@
> #include "llvm/CodeGen/MachineCodeEmitter.h"
> #include "llvm/CodeGen/MachineFunctionPass.h"
> #include "llvm/CodeGen/MachineInstr.h"
> +#include "llvm/CodeGen/MachineModuleInfo.h"
> #include "llvm/CodeGen/Passes.h"
> #include "llvm/Function.h"
> #include "llvm/ADT/Statistic.h"
> @@ -61,6 +62,11 @@
>
>     void emitInstruction(const MachineInstr &MI,
>                          const TargetInstrDesc *Desc);
> +
> +    void getAnalysisUsage(AnalysisUsage &AU) const {
> +      AU.addRequired<MachineModuleInfo>();
> +      MachineFunctionPass::getAnalysisUsage(AU);
> +    }
>
>   private:
>     void emitPCRelativeBlockAddress(MachineBasicBlock *MBB);
> @@ -104,10 +110,13 @@
>   assert((MF.getTarget().getRelocationModel() != Reloc::Default ||
>           MF.getTarget().getRelocationModel() != Reloc::Static) &&
>          "JIT relocation model must be set to static or default!");
> +
> +  MCE.setModuleInfo(&getAnalysis<MachineModuleInfo>());
> +
>   II = ((X86TargetMachine&)TM).getInstrInfo();
>   TD = ((X86TargetMachine&)TM).getTargetData();
>   Is64BitMode = TM.getSubtarget<X86Subtarget>().is64Bit();
> -
> +
>   do {
>     MCE.startFunction(MF);
>     for (MachineFunction::iterator MBB = MF.begin(), E = MF.end();
> @@ -596,13 +605,13 @@
>     // Remember the current PC offset, this is the PIC relocation
>     // base address.
>     switch (Opcode) {
> -#ifndef NDEBUG
>     default:
>       assert(0 && "psuedo instructions should be removed before code  
> emission");
>     case TargetInstrInfo::INLINEASM:
>       assert(0 && "JIT does not support inline asm!\n");
>     case TargetInstrInfo::LABEL:
> -      assert(0 && "JIT does not support meta labels!\n");
> +      MCE.emitLabel(MI.getOperand(0).getImm());
> +      break;
>     case X86::IMPLICIT_DEF_GR8:
>     case X86::IMPLICIT_DEF_GR16:
>     case X86::IMPLICIT_DEF_GR32:
> @@ -613,7 +622,6 @@
>     case X86::IMPLICIT_DEF_VR128:
>     case X86::FP_REG_KILL:
>       break;
> -#endif
>     case X86::MOVPC32r: {
>       // This emits the "call" portion of this pseudo instruction.
>       MCE.emitByte(BaseOpcode);
> @@ -627,7 +635,6 @@
>     }
>     CurOp = NumOps;
>     break;
> -
>   case X86II::RawFrm:
>     MCE.emitByte(BaseOpcode);
>
> Index: lib/ExecutionEngine/JIT/JITEmitter.cpp
> ===================================================================
> --- lib/ExecutionEngine/JIT/JITEmitter.cpp	(revision 46612)
> +++ lib/ExecutionEngine/JIT/JITEmitter.cpp	(working copy)
> @@ -14,6 +14,7 @@
>
> #define DEBUG_TYPE "jit"
> #include "JIT.h"
> +#include "JITDwarfEmitter.h"
> #include "llvm/Constant.h"
> #include "llvm/Module.h"
> #include "llvm/Type.h"
> @@ -21,11 +22,13 @@
> #include "llvm/CodeGen/MachineFunction.h"
> #include "llvm/CodeGen/MachineConstantPool.h"
> #include "llvm/CodeGen/MachineJumpTableInfo.h"
> +#include "llvm/CodeGen/MachineModuleInfo.h"
> #include "llvm/CodeGen/MachineRelocation.h"
> #include "llvm/ExecutionEngine/JITMemoryManager.h"
> #include "llvm/Target/TargetData.h"
> #include "llvm/Target/TargetJITInfo.h"
> #include "llvm/Target/TargetMachine.h"
> +#include "llvm/Target/TargetOptions.h"
> #include "llvm/Support/Debug.h"
> #include "llvm/Support/MutexGuard.h"
> #include "llvm/System/Disassembler.h"
> @@ -336,6 +339,17 @@
>
>     /// Resolver - This contains info about the currently resolved  
> functions.
>     JITResolver Resolver;
> +
> +    /// DE - The dwarf emitter for the jit.
> +    JITDwarfEmitter *DE;
> +
> +    /// LabelLocations - This vector is a mapping from Label ID's  
> to their
> +    /// address.
> +    std::vector<intptr_t> LabelLocations;
> +
> +    /// MMI - Machine module info for exception informations
> +    MachineModuleInfo* MMI;
> +
>   public:
>     JITEmitter(JIT &jit, JITMemoryManager *JMM) : Resolver(jit) {
>       MemMgr = JMM ? JMM :  
> JITMemoryManager::CreateDefaultMemManager();
> @@ -343,9 +357,12 @@
>         MemMgr->AllocateGOT();
>         DOUT << "JIT is managing a GOT\n";
>       }
> +
> +      if (ExceptionHandling) DE = new JITDwarfEmitter(jit);
>     }
>     ~JITEmitter() {
>       delete MemMgr;
> +      if (ExceptionHandling) delete DE;
>     }
>
>     JITResolver &getJITResolver() { return Resolver; }
> @@ -384,6 +401,24 @@
>     void deallocateMemForFunction(Function *F) {
>       MemMgr->deallocateMemForFunction(F);
>     }
> +
> +    virtual void emitLabel(uint64_t LabelID) {
> +      if (LabelLocations.size() <= LabelID)
> +        LabelLocations.resize((LabelID+1)*2);
> +      LabelLocations[LabelID] = getCurrentPCValue();
> +    }
> +
> +    virtual intptr_t getLabelAddress(uint64_t LabelID) const {
> +      assert(LabelLocations.size() > (unsigned)LabelID &&
> +             LabelLocations[LabelID] && "Label not emitted!");
> +      return LabelLocations[LabelID];
> +    }
> +
> +    virtual void setModuleInfo(MachineModuleInfo* Info) {
> +      MMI = Info;
> +      if (ExceptionHandling) DE->setModuleInfo(Info);
> +    }
> +
>   private:
>     void *getPointerToGlobal(GlobalValue *GV, void *Reference, bool  
> NoNeedStub);
>     void *getPointerToGVLazyPtr(GlobalValue *V, void *Reference,
> @@ -544,7 +579,25 @@
>     DOUT << "Disassembled code:\n"
>          << sys::disassembleBuffer(FnStart, FnEnd-FnStart,  
> (uintptr_t)FnStart);
> #endif
> -
> +  if (ExceptionHandling) {
> +    uintptr_t ActualSize;
> +    SavedBufferBegin = BufferBegin;
> +    SavedBufferEnd = BufferEnd;
> +    SavedCurBufferPtr = CurBufferPtr;
> +
> +    BufferBegin = CurBufferPtr = MemMgr- 
> >startExceptionTable(F.getFunction(),
> +                                                              
> ActualSize);
> +    BufferEnd = BufferBegin+ActualSize;
> +    unsigned char* FrameRegister = DE->EmitDwarfTable(F, *this,  
> FnStart, FnEnd);
> +    MemMgr->endExceptionTable(F.getFunction(), BufferBegin,  
> CurBufferPtr, FrameRegister);
> +    BufferBegin = SavedBufferBegin;
> +    BufferEnd = SavedBufferEnd;
> +    CurBufferPtr = SavedCurBufferPtr;
> +
> +    TheJIT->RegisterTable(FrameRegister);
> +  }
> +  MMI->EndFunction();
> +
>   return false;
> }
>
> Index: lib/ExecutionEngine/JIT/JITMemoryManager.cpp
> ===================================================================
> --- lib/ExecutionEngine/JIT/JITMemoryManager.cpp	(revision 46612)
> +++ lib/ExecutionEngine/JIT/JITMemoryManager.cpp	(working copy)
> @@ -256,6 +256,7 @@
>     sys::MemoryBlock getNewMemoryBlock(unsigned size);
>
>     std::map<const Function*, MemoryRangeHeader*> FunctionBlocks;
> +    std::map<const Function*, MemoryRangeHeader*> TableBlocks;
>   public:
>     DefaultJITMemoryManager();
>     ~DefaultJITMemoryManager();
> @@ -290,6 +291,28 @@
>       FreeMemoryList =CurBlock->TrimAllocationToSize(FreeMemoryList,  
> BlockSize);
>     }
>
> +    /// startExceptionTable - Use startFunctionBody to allocate  
> memory for the
> +    /// function's exception table.
> +    unsigned char* 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, unsigned char  
> *TableStart,
> +                           unsigned char *TableEnd,
> +                           unsigned char* FrameRegister) {
> +      assert(TableEnd > TableStart);
> +      assert(TableStart == (unsigned char *)(CurBlock+1) &&
> +             "Mismatched table start/end!");
> +
> +      uintptr_t BlockSize = TableEnd - (unsigned char *)CurBlock;
> +      TableBlocks[F] = CurBlock;
> +
> +      // Release the memory at the end of this block that isn't  
> needed.
> +      FreeMemoryList =CurBlock- 
> >TrimAllocationToSize(FreeMemoryList, BlockSize);
> +    }
> +
>     unsigned char *getGOTBase() const {
>       return GOTBase;
>     }
> @@ -315,6 +338,24 @@
>
>       // Finally, remove this entry from FunctionBlocks.
>       FunctionBlocks.erase(I);
> +
> +      I = TableBlocks.find(F);
> +      if (I == TableBlocks.end()) return;
> +
> +      // Find the block that is allocated for this function.
> +      MemRange = I->second;
> +      assert(MemRange->ThisAllocated && "Block isn't allocated!");
> +
> +      // Fill the buffer with garbage!
> +#ifndef NDEBUG
> +      memset(MemRange+1, 0xCD, MemRange->BlockSize- 
> sizeof(*MemRange));
> +#endif
> +
> +      // Free the memory.
> +      FreeMemoryList = MemRange->FreeBlock(FreeMemoryList);
> +
> +      // Finally, remove this entry from TableBlocks.
> +      TableBlocks.erase(I);
>     }
>   };
> }
> Index: lib/ExecutionEngine/ExecutionEngine.cpp
> ===================================================================
> --- lib/ExecutionEngine/ExecutionEngine.cpp	(revision 46612)
> +++ lib/ExecutionEngine/ExecutionEngine.cpp	(working copy)
> @@ -34,7 +34,9 @@
>
> ExecutionEngine::EECtorFn ExecutionEngine::JITCtor = 0;
> ExecutionEngine::EECtorFn ExecutionEngine::InterpCtor = 0;
> +ExecutionEngine::EERegisterFn  
> ExecutionEngine::ExceptionTableRegister = 0;
>
> +
> ExecutionEngine::ExecutionEngine(ModuleProvider *P) :  
> LazyFunctionCreator(0) {
>   LazyCompilationDisabled = false;
>   Modules.push_back(P);
> Index: lib/ExecutionEngine/JIT/JITDwarfEmitter.h
> ===================================================================
> --- lib/ExecutionEngine/JIT/JITDwarfEmitter.h	(revision 0)
> +++ lib/ExecutionEngine/JIT/JITDwarfEmitter.h	(revision 0)
> @@ -0,0 +1,69 @@
> +//===------ JITDwarfEmitter.h - 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.
> +//
> +// 
> = 
> = 
> = 
> ----------------------------------------------------------------------= 
> ==//
> +
> +#ifndef LLVM_EXECUTION_ENGINE_JIT_DWARFEMITTER_H
> +#define LLVM_EXECUTION_ENGINE_JIT_DWARFEMITTER_H
> +
> +namespace llvm {
> +
> +class Function;
> +class MachineCodeEmitter;
> +class MachineFunction;
> +class MachineModuleInfo;
> +class MachineMove;
> +class MRegisterInfo;
> +class TargetData;
> +class TargetMachine;
> +
> +class JITDwarfEmitter {
> +  const TargetData* TD;
> +  MachineCodeEmitter* MCE;
> +  const MRegisterInfo* RI;
> +  MachineModuleInfo* MMI;
> +  JIT& Jit;
> +  bool needsIndirectEncoding;
> +  bool stackGrowthDirection;
> +
> +public:
> +  JITDwarfEmitter(JIT& jit);
> +
> +  unsigned char* EmitExceptionTable(MachineFunction* MF,
> +                                    unsigned char* StartFunction,
> +                                    unsigned char* EndFunction);
> +
> +  void EmitFrameMoves(intptr_t BaseLabelPtr,
> +                      const std::vector<MachineMove> &Moves);
> +
> +  unsigned char* EmitCommonEHFrame(const Function* Personality);
> +
> +  unsigned char* EmitEHFrame(const Function* Personality,
> +                             unsigned char* StartBufferPtr,
> +                             unsigned char* StartFunction,
> +                             unsigned char* EndFunction,
> +                             unsigned char* ExceptionTable);
> +
> +
> +  unsigned char* EmitDwarfTable(MachineFunction& F,
> +                                MachineCodeEmitter& MCE,
> +                                unsigned char* StartFunction,
> +                                unsigned char* EndFunction);
> +
> +  void setModuleInfo(MachineModuleInfo* Info) {
> +    MMI = Info;
> +  }
> +};
> +
> +} // end namespace llvm
> +
> +#endif // LLVM_EXECUTION_ENGINE_JIT_DWARFEMITTER_H
> Index: lib/ExecutionEngine/JIT/JITDwarfEmitter.cpp
> ===================================================================
> --- lib/ExecutionEngine/JIT/JITDwarfEmitter.cpp	(revision 0)
> +++ lib/ExecutionEngine/JIT/JITDwarfEmitter.cpp	(revision 0)
> @@ -0,0 +1,636 @@
> +//===----- 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 "JIT.h"
> +#include "JITDwarfEmitter.h"
> +#include "llvm/Function.h"
> +#include "llvm/ADT/DenseMap.h"
> +#include "llvm/CodeGen/AsmPrinter.h"
> +#include "llvm/CodeGen/MachineCodeEmitter.h"
> +#include "llvm/CodeGen/MachineFunction.h"
> +#include "llvm/CodeGen/MachineLocation.h"
> +#include "llvm/CodeGen/MachineModuleInfo.h"
> +#include "llvm/ExecutionEngine/JITMemoryManager.h"
> +#include "llvm/Target/MRegisterInfo.h"
> +#include "llvm/Target/TargetAsmInfo.h"
> +#include "llvm/Target/TargetData.h"
> +#include "llvm/Target/TargetInstrInfo.h"
> +#include "llvm/Target/TargetFrameInfo.h"
> +#include "llvm/Target/TargetMachine.h"
> +
> +using namespace llvm;
> +
> +JITDwarfEmitter::JITDwarfEmitter(JIT& theJit) : Jit(theJit) {}
> +
> +
> +unsigned char* JITDwarfEmitter::EmitDwarfTable(MachineFunction& F,
> +                                               MachineCodeEmitter&  
> mce,
> +                                               unsigned char*  
> StartFunction,
> +                                               unsigned char*  
> EndFunction) {
> +  const TargetMachine& TM = F.getTarget();
> +  TD = TM.getTargetData();
> +  needsIndirectEncoding = TM.getTargetAsmInfo()- 
> >getNeedsIndirectEncoding();
> +  stackGrowthDirection = TM.getFrameInfo()- 
> >getStackGrowthDirection();
> +  RI = TM.getRegisterInfo();
> +  MCE = &mce;
> +
> +  unsigned char* ExceptionTable = EmitExceptionTable(&F,  
> StartFunction,
> +                                                     EndFunction);
> +
> +  unsigned char* Result = 0;
> +  unsigned char* EHFramePtr = 0;
> +
> +  const std::vector<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) {
> +  unsigned PointerSize = TD->getPointerSize();
> +  int stackGrowth = stackGrowthDirection ==  
> TargetFrameInfo::StackGrowsUp ?
> +          PointerSize : -PointerSize;
> +  bool IsLocal = BaseLabelPtr;
> +
> +  for (unsigned i = 0, N = Moves.size(); i < N; ++i) {
> +    const MachineMove &Move = Moves[i];
> +    unsigned LabelID = Move.getLabelID();
> +
> +    if (LabelID) {
> +      LabelID = MMI->MappedLabel(LabelID);
> +
> +      // Throw out move if the label is invalid.
> +      if (!LabelID) continue;
> +    }
> +
> +    intptr_t LabelPtr = 0;
> +    if (LabelID) LabelPtr = MCE->getLabelAddress(LabelID);
> +
> +    const MachineLocation &Dst = Move.getDestination();
> +    const MachineLocation &Src = Move.getSource();
> +
> +    // Advance row if new location.
> +    if (BaseLabelPtr && LabelID && (BaseLabelPtr != LabelPtr || ! 
> IsLocal)) {
> +      MCE->emitByte(dwarf::DW_CFA_advance_loc4);
> +      if (PointerSize == 8) {
> +        MCE->emitInt64(LabelPtr - BaseLabelPtr);
> +      } else {
> +        MCE->emitInt32(LabelPtr - BaseLabelPtr);
> +      }
> +
> +      BaseLabelPtr = LabelPtr;
> +      IsLocal = true;
> +    }
> +
> +    // If advancing cfa.
> +    if (Dst.isRegister() && Dst.getRegister() ==  
> MachineLocation::VirtualFP) {
> +      if (!Src.isRegister()) {
> +        if (Src.getRegister() == MachineLocation::VirtualFP) {
> +          MCE->emitByte(dwarf::DW_CFA_def_cfa_offset);
> +        } else {
> +          MCE->emitByte(dwarf::DW_CFA_def_cfa);
> +          MCE->emitULEB128Bytes(RI- 
> >getDwarfRegNum(Src.getRegister(), true));
> +        }
> +
> +        int Offset = -Src.getOffset();
> +
> +        MCE->emitULEB128Bytes(Offset);
> +      } else {
> +        assert(0 && "Machine move no supported yet.");
> +      }
> +    } else if (Src.isRegister() &&
> +      Src.getRegister() == MachineLocation::VirtualFP) {
> +      if (Dst.isRegister()) {
> +        MCE->emitByte(dwarf::DW_CFA_def_cfa_register);
> +        MCE->emitULEB128Bytes(RI->getDwarfRegNum(Dst.getRegister(),  
> true));
> +      } else {
> +        assert(0 && "Machine move no supported yet.");
> +      }
> +    } else {
> +      unsigned Reg = RI->getDwarfRegNum(Src.getRegister(), true);
> +      int Offset = Dst.getOffset() / stackGrowth;
> +
> +      if (Offset < 0) {
> +        MCE->emitByte(dwarf::DW_CFA_offset_extended_sf);
> +        MCE->emitULEB128Bytes(Reg);
> +        MCE->emitSLEB128Bytes(Offset);
> +      } else if (Reg < 64) {
> +        MCE->emitByte(dwarf::DW_CFA_offset + Reg);
> +        MCE->emitULEB128Bytes(Offset);
> +      } else {
> +        MCE->emitByte(dwarf::DW_CFA_offset_extended);
> +        MCE->emitULEB128Bytes(Reg);
> +        MCE->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;
> +}
> +
> +struct KeyInfo {
> +  static inline unsigned getEmptyKey() { return -1U; }
> +  static inline unsigned getTombstoneKey() { return -2U; }
> +  static unsigned getHashValue(const unsigned &Key) { return Key; }
> +  static bool isEqual(unsigned LHS, unsigned RHS) { return LHS ==  
> RHS; }
> +  static bool isPod() { return true; }
> +};
> +
> +/// 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<unsigned, PadRange, KeyInfo> RangeMapType;
> +
> +/// CallSiteEntry - Structure describing an entry in the call-site  
> table.
> +struct CallSiteEntry {
> +  unsigned BeginLabel; // zero indicates the start of the function.
> +  unsigned EndLabel;   // zero indicates the end of the function.
> +  unsigned PadLabel;   // zero indicates that there is no landing  
> pad.
> +  unsigned Action;
> +};
> +
> +unsigned char* JITDwarfEmitter::EmitExceptionTable(MachineFunction*  
> MF,
> +                                         unsigned char*  
> StartFunction,
> +                                         unsigned char*  
> EndFunction) {
> +  // Map all labels and get rid of any dead landing pads.
> +  MMI->TidyLandingPads();
> +
> +  const std::vector<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 -= AsmPrinter::SizeULEB128(*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 = AsmPrinter::SizeSLEB128(PrevAction- 
> >NextAction) +
> +          AsmPrinter::SizeSLEB128(PrevAction->ValueForTypeID);
> +        for (unsigned j = NumShared; j != SizePrevIds; ++j) {
> +          SizeAction -= AsmPrinter::SizeSLEB128(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 =  
> AsmPrinter::SizeSLEB128(ValueForTypeID);
> +
> +        int NextAction = SizeAction ? -(SizeAction + SizeTypeID) : 0;
> +        SizeAction = SizeTypeID +  
> AsmPrinter::SizeSLEB128(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) {
> +      unsigned BeginLabel = LandingPad->BeginLabels[j];
> +      assert(!PadMap.count(BeginLabel) && "Duplicate landing pad  
> labels!");
> +      PadRange P = { i, j };
> +      PadMap[BeginLabel] = P;
> +    }
> +  }
> +
> +  bool MayThrow = false;
> +  unsigned 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->getOpcode() != TargetInstrInfo::LABEL) {
> +        MayThrow |= MI->getDesc().isCall();
> +        continue;
> +      }
> +
> +      unsigned BeginLabel = MI->getOperand(0).getImm();
> +      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[CallSites.size()-1];
> +        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 += AsmPrinter::SizeULEB128(CallSites[i].Action);
> +
> +  unsigned SizeTypes = TypeInfos.size() * TD->getPointerSize();
> +
> +  unsigned TypeOffset = sizeof(int8_t) + // Call site format
> +                        // Call-site table length
> +                        AsmPrinter::SizeULEB128(SizeSites) +
> +                        SizeSites + SizeActions + SizeTypes;
> +
> +  unsigned TotalSize = sizeof(int8_t) + // LPStart format
> +                       sizeof(int8_t) + // TType format
> +                       AsmPrinter::SizeULEB128(TypeOffset) + //  
> TType base offset
> +                       TypeOffset;
> +
> +  unsigned SizeAlign = (4 - TotalSize) & 3;
> +
> +  // Begin the exception table.
> +  MCE->emitAlignment(4);
> +  for (unsigned i = 0; i != SizeAlign; ++i) {
> +    MCE->emitByte(0);
> +    // Asm->EOL("Padding");
> +  }
> +
> +  unsigned char* DwarfExceptionTable = (unsigned char*)MCE- 
> >getCurrentPCValue();
> +
> +  // Emit the header.
> +  MCE->emitByte(dwarf::DW_EH_PE_omit);
> +  // Asm->EOL("LPStart format (DW_EH_PE_omit)");
> +  MCE->emitByte(dwarf::DW_EH_PE_absptr);
> +  // Asm->EOL("TType format (DW_EH_PE_absptr)");
> +  MCE->emitULEB128Bytes(TypeOffset);
> +  // Asm->EOL("TType base offset");
> +  MCE->emitByte(dwarf::DW_EH_PE_udata4);
> +  // Asm->EOL("Call site format (DW_EH_PE_udata4)");
> +  MCE->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;
> +      if (TD->getPointerSize() == sizeof(int32_t))
> +        MCE->emitInt32(0);
> +      else
> +        MCE->emitInt64(0);
> +    } else {
> +      BeginLabelPtr = MCE->getLabelAddress(S.BeginLabel);
> +      if (TD->getPointerSize() == sizeof(int32_t))
> +        MCE->emitInt32(BeginLabelPtr - (intptr_t)StartFunction);
> +      else
> +        MCE->emitInt64(BeginLabelPtr - (intptr_t)StartFunction);
> +    }
> +
> +    // Asm->EOL("Region start");
> +
> +    if (!S.EndLabel) {
> +      EndLabelPtr = (intptr_t)EndFunction;
> +      if (TD->getPointerSize() == sizeof(int32_t))
> +        MCE->emitInt32((intptr_t)EndFunction - BeginLabelPtr);
> +      else
> +        MCE->emitInt64((intptr_t)EndFunction - BeginLabelPtr);
> +    } else {
> +      EndLabelPtr = MCE->getLabelAddress(S.EndLabel);
> +      if (TD->getPointerSize() == sizeof(int32_t))
> +        MCE->emitInt32(EndLabelPtr - BeginLabelPtr);
> +      else
> +        MCE->emitInt64(EndLabelPtr - BeginLabelPtr);
> +    }
> +    //Asm->EOL("Region length");
> +
> +    if (!S.PadLabel) {
> +      if (TD->getPointerSize() == sizeof(int32_t))
> +        MCE->emitInt32(0);
> +      else
> +        MCE->emitInt64(0);
> +    } else {
> +      unsigned PadLabelPtr = MCE->getLabelAddress(S.PadLabel);
> +      if (TD->getPointerSize() == sizeof(int32_t))
> +        MCE->emitInt32(PadLabelPtr - (intptr_t)StartFunction);
> +      else
> +        MCE->emitInt64(PadLabelPtr - (intptr_t)StartFunction);
> +    }
> +    // Asm->EOL("Landing pad");
> +
> +    MCE->emitULEB128Bytes(S.Action);
> +    // Asm->EOL("Action");
> +  }
> +
> +  // Emit the actions.
> +  for (unsigned I = 0, N = Actions.size(); I != N; ++I) {
> +    ActionEntry &Action = Actions[I];
> +
> +    MCE->emitSLEB128Bytes(Action.ValueForTypeID);
> +    //Asm->EOL("TypeInfo index");
> +    MCE->emitSLEB128Bytes(Action.NextAction);
> +    //Asm->EOL("Next action");
> +  }
> +
> +  // Emit the type ids.
> +  for (unsigned M = TypeInfos.size(); M; --M) {
> +    GlobalVariable *GV = TypeInfos[M - 1];
> +
> +    if (GV) {
> +      if (TD->getPointerSize() == sizeof(int32_t)) {
> +        MCE->emitInt32((intptr_t)Jit.getOrEmitGlobalVariable(GV));
> +      } else {
> +        MCE->emitInt64((intptr_t)Jit.getOrEmitGlobalVariable(GV));
> +      }
> +    } else {
> +      if (TD->getPointerSize() == sizeof(int32_t))
> +        MCE->emitInt32(0);
> +      else
> +        MCE->emitInt64(0);
> +    }
> +    // Asm->EOL("TypeInfo");
> +  }
> +
> +  // Emit the filter typeids.
> +  for (unsigned j = 0, M = FilterIds.size(); j < M; ++j) {
> +    unsigned TypeID = FilterIds[j];
> +    MCE->emitULEB128Bytes(TypeID);
> +    //Asm->EOL("Filter TypeInfo index");
> +  }
> +
> +  MCE->emitAlignment(4);
> +
> +  return DwarfExceptionTable;
> +}
> +
> +unsigned char* JITDwarfEmitter::EmitCommonEHFrame(const Function*  
> Personality) {
> +  unsigned PointerSize = TD->getPointerSize();
> +  int stackGrowth = stackGrowthDirection ==  
> TargetFrameInfo::StackGrowsUp ?
> +          PointerSize : -PointerSize;
> +
> +  unsigned char* StartCommonPtr = (unsigned char*)MCE- 
> >getCurrentPCValue();
> +  // EH Common Frame header
> +  MCE->allocateSpace(PointerSize, 0);
> +  unsigned char* FrameCommonBeginPtr = (unsigned char*)MCE- 
> >getCurrentPCValue();
> +  MCE->emitInt32((int)0);
> +  MCE->emitByte(dwarf::DW_CIE_VERSION);
> +  MCE->emitString(Personality ? "zPLR" : "zR");
> +  MCE->emitULEB128Bytes(1);
> +  MCE->emitSLEB128Bytes(stackGrowth);
> +  MCE->emitByte(RI->getDwarfRegNum(RI->getRARegister(), true));
> +
> +  if (Personality) {
> +    MCE->emitULEB128Bytes(7);
> +
> +    if (needsIndirectEncoding)
> +      MCE->emitByte(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 |
> +               dwarf::DW_EH_PE_indirect);
> +    else
> +      MCE->emitByte(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4);
> +
> +    if (PointerSize == 8)
> +      MCE->emitInt64((intptr_t)Jit.getPointerToGlobal(Personality) -
> +                MCE->getCurrentPCValue());
> +    else
> +      MCE->emitInt32((intptr_t)Jit.getPointerToGlobal(Personality) -
> +                MCE->getCurrentPCValue());
> +
> +    MCE->emitULEB128Bytes(dwarf::DW_EH_PE_pcrel);
> +    MCE->emitULEB128Bytes(dwarf::DW_EH_PE_pcrel);
> +
> +  } else {
> +    MCE->emitULEB128Bytes(1);
> +    MCE->emitULEB128Bytes(dwarf::DW_EH_PE_pcrel);
> +  }
> +
> +  std::vector<MachineMove> Moves;
> +  RI->getInitialFrameState(Moves);
> +  EmitFrameMoves(0, Moves);
> +  MCE->emitAlignment(4);
> +
> +  MCE->emitAt((uintptr_t*)StartCommonPtr,
> +              (uintptr_t)((unsigned char*)MCE->getCurrentPCValue() -
> +                          FrameCommonBeginPtr));
> +
> +  return StartCommonPtr;
> +}
> +
> +
> +unsigned char* JITDwarfEmitter::EmitEHFrame(const Function*  
> Personality,
> +                                            unsigned char*  
> StartCommonPtr,
> +                                            unsigned char*  
> StartFunction,
> +                                            unsigned char*  
> EndFunction,
> +                                            unsigned char*  
> ExceptionTable) {
> +  unsigned PointerSize = TD->getPointerSize();
> +
> +  // EH frame header.
> +  unsigned char* StartEHPtr = (unsigned char*)MCE- 
> >getCurrentPCValue();
> +  MCE->allocateSpace(PointerSize, 0);
> +  unsigned char* FrameBeginPtr = (unsigned char*)MCE- 
> >getCurrentPCValue();
> +  // FDE CIE Offset
> +  if (PointerSize == 8) {
> +    MCE->emitInt64(FrameBeginPtr - StartCommonPtr);
> +    MCE->emitInt64(StartFunction - (unsigned char*)MCE- 
> >getCurrentPCValue());
> +    MCE->emitInt64(EndFunction - StartFunction);
> +  } else {
> +    MCE->emitInt32(FrameBeginPtr - StartCommonPtr);
> +    MCE->emitInt32(StartFunction - (unsigned char*)MCE- 
> >getCurrentPCValue());
> +    MCE->emitInt32(EndFunction - StartFunction);
> +  }
> +
> +  // If there is a personality and landing pads then point to the  
> language
> +  // specific data area in the exception table.
> +  if (MMI->getPersonalityIndex()) {
> +    MCE->emitULEB128Bytes(4);
> +
> +    if (!MMI->getLandingPads().empty()) {
> +      if (PointerSize == 8)
> +        MCE->emitInt64(ExceptionTable - (unsigned char*)MCE- 
> >getCurrentPCValue());
> +      else
> +        MCE->emitInt32(ExceptionTable - (unsigned char*)MCE- 
> >getCurrentPCValue());
> +    } else if (PointerSize == 8) {
> +      MCE->emitInt64((int)0);
> +    } else {
> +      MCE->emitInt32((int)0);
> +    }
> +  } else {
> +    MCE->emitULEB128Bytes(0);
> +  }
> +
> +  // Indicate locations of function specific  callee saved  
> registers in
> +  // frame.
> +  EmitFrameMoves((intptr_t)StartFunction, MMI->getFrameMoves());
> +
> +  MCE->emitAlignment(4);
> +
> +  // Indicate the size of the table
> +  MCE->emitAt((uintptr_t*)StartEHPtr,
> +              (uintptr_t)((unsigned char*)MCE->getCurrentPCValue() -
> +                          StartEHPtr));
> +
> +  // Double zeroes for the unwind runtime
> +  if (PointerSize == 8) {
> +    MCE->emitInt64(0);
> +    MCE->emitInt64(0);
> +  } else {
> +    MCE->emitInt32(0);
> +    MCE->emitInt32(0);
> +  }
> +
> +
> +  return StartEHPtr;
> +}
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev




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