lib/CodeGen/AsmPrinter/ARMException.cpp

   1 //===-- CodeGen/AsmPrinter/ARMException.cpp - ARM EHABI Exception Impl ----===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file contains support for writing DWARF exception info into asm files.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "DwarfException.h"
  15 #include "llvm/Module.h"
  16 #include "llvm/CodeGen/AsmPrinter.h"
  17 #include "llvm/CodeGen/MachineModuleInfo.h"
  18 #include "llvm/CodeGen/MachineFrameInfo.h"
  19 #include "llvm/CodeGen/MachineFunction.h"
  20 #include "llvm/MC/MCAsmInfo.h"
  21 #include "llvm/MC/MCContext.h"
  22 #include "llvm/MC/MCExpr.h"
  23 #include "llvm/MC/MCSection.h"
  24 #include "llvm/MC/MCStreamer.h"
  25 #include "llvm/MC/MCSymbol.h"
  26 #include "llvm/Target/Mangler.h"
  27 #include "llvm/Target/TargetData.h"
  28 #include "llvm/Target/TargetFrameLowering.h"
  29 #include "llvm/Target/TargetMachine.h"
  30 #include "llvm/Target/TargetOptions.h"
  31 #include "llvm/Target/TargetRegisterInfo.h"
  32 #include "llvm/Support/CommandLine.h"
  33 #include "llvm/Support/Dwarf.h"
  34 #include "llvm/Support/FormattedStream.h"
  35 #include "llvm/ADT/SmallString.h"
  36 #include "llvm/ADT/StringExtras.h"
  37 #include "llvm/ADT/Twine.h"
  38 using namespace llvm;
  39
  40 cl::opt<ExceptionHandling::ARMEHABIMode>
  41 EnableARMEHABI("arm-enable-ehabi", cl::Hidden,
  42     cl::desc("Generate ARM EHABI tables:"),
  43     cl::values(clEnumValN(ExceptionHandling::ARMEHABIDisabled, "no",
  44             "Do not generate ARM EHABI tables"),
  45         clEnumValN(ExceptionHandling::ARMEHABIUnwind, "unwind",
  46             "Emit unwinding instructions, but not descriptors"),
  47         clEnumValN(ExceptionHandling::ARMEHABIFull, "full",
  48             "Generate full ARM EHABI tables"),
  49         clEnumValEnd));
  50
  51
  52 ARMException::ARMException(AsmPrinter *A)
  53   : DwarfException(A),
  54     shouldEmitTable(false), shouldEmitMoves(false), shouldEmitTableModule(false)
  55     {}
  56
  57 ARMException::~ARMException() {}
  58
  59 void ARMException::EndModule() {
  60 }
  61
  62 /// BeginFunction - Gather pre-function exception information. Assumes it's
  63 /// being emitted immediately after the function entry point.
  64 void ARMException::BeginFunction(const MachineFunction *MF) {
  65   Asm->OutStreamer.EmitFnStart();
  66   if (Asm->MF->getFunction()->needsUnwindTableEntry())
  67     Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_begin",
  68                                                   Asm->getFunctionNumber()));
  69 }
  70
  71 /// EndFunction - Gather and emit post-function exception information.
  72 ///
  73 void ARMException::EndFunction() {
  74   if (!Asm->MF->getFunction()->needsUnwindTableEntry())
  75     Asm->OutStreamer.EmitCantUnwind();
  76   else {
  77     Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_end",
  78                                                   Asm->getFunctionNumber()));
  79
  80     // Emit references to personality.
  81     if (const Function * Personality =
  82         MMI->getPersonalities()[MMI->getPersonalityIndex()]) {
  83       MCSymbol *PerSym = Asm->Mang->getSymbol(Personality);
  84       Asm->OutStreamer.EmitSymbolAttribute(PerSym, MCSA_Global);
  85       Asm->OutStreamer.EmitPersonality(PerSym);
  86     }
  87
  88     if (EnableARMEHABI == ExceptionHandling::ARMEHABIFull) {
  89       // Map all labels and get rid of any dead landing pads.
  90       MMI->TidyLandingPads();
  91
  92       Asm->OutStreamer.EmitHandlerData();
  93
  94       // Emit actual exception table
  95       EmitExceptionTable();
  96     }
  97   }
  98
  99   Asm->OutStreamer.EmitFnEnd();
 100 }