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"
38using namespace llvm;
39
40cl::opt<bool>
41EnableARMEHABIDescriptors("arm-enable-ehabi-descriptors", cl::Hidden,
42  cl::desc("Generate ARM EHABI tables with unwinding descriptors"),
43  cl::init(false));
44
45
46ARMException::ARMException(AsmPrinter *A)
47  : DwarfException(A) {}
48
49ARMException::~ARMException() {}
50
51void ARMException::EndModule() {
52}
53
54/// BeginFunction - Gather pre-function exception information. Assumes it's
55/// being emitted immediately after the function entry point.
56void ARMException::BeginFunction(const MachineFunction *MF) {
57  Asm->OutStreamer.EmitFnStart();
58  if (Asm->MF->getFunction()->needsUnwindTableEntry())
59    Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_begin",
60                                                  Asm->getFunctionNumber()));
61}
62
63/// EndFunction - Gather and emit post-function exception information.
64///
65void ARMException::EndFunction() {
66  if (!Asm->MF->getFunction()->needsUnwindTableEntry())
67    Asm->OutStreamer.EmitCantUnwind();
68  else {
69    Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_end",
70                                                  Asm->getFunctionNumber()));
71
72    // Emit references to personality.
73    if (const Function * Personality =
74        MMI->getPersonalities()[MMI->getPersonalityIndex()]) {
75      MCSymbol *PerSym = Asm->Mang->getSymbol(Personality);
76      Asm->OutStreamer.EmitSymbolAttribute(PerSym, MCSA_Global);
77      Asm->OutStreamer.EmitPersonality(PerSym);
78    }
79
80    if (EnableARMEHABIDescriptors) {
81      // Map all labels and get rid of any dead landing pads.
82      MMI->TidyLandingPads();
83
84      Asm->OutStreamer.EmitHandlerData();
85
86      // Emit actual exception table
87      EmitExceptionTable();
88    }
89  }
90
91  Asm->OutStreamer.EmitFnEnd();
92}
93