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/CodeGen/MachineLocation.h"
21 #include "llvm/MC/MCAsmInfo.h"
22 #include "llvm/MC/MCContext.h"
23 #include "llvm/MC/MCExpr.h"
24 #include "llvm/MC/MCSection.h"
25 #include "llvm/MC/MCStreamer.h"
26 #include "llvm/MC/MCSymbol.h"
27 #include "llvm/Target/Mangler.h"
28 #include "llvm/Target/TargetData.h"
29 #include "llvm/Target/TargetFrameLowering.h"
30 #include "llvm/Target/TargetLoweringObjectFile.h"
31 #include "llvm/Target/TargetMachine.h"
32 #include "llvm/Target/TargetOptions.h"
33 #include "llvm/Target/TargetRegisterInfo.h"
34 #include "llvm/Support/Dwarf.h"
35 #include "llvm/Support/FormattedStream.h"
36 #include "llvm/ADT/SmallString.h"
37 #include "llvm/ADT/StringExtras.h"
38 #include "llvm/ADT/Twine.h"
39 using namespace llvm;
40 
41 ARMException::ARMException(AsmPrinter *A)
42   : DwarfException(A),
43     shouldEmitTable(false), shouldEmitMoves(false), shouldEmitTableModule(false)
44     {}
45 
46 ARMException::~ARMException() {}
47 
48 void ARMException::EndModule() {
49 }
50 
51 /// BeginFunction - Gather pre-function exception information. Assumes it's
52 /// being emitted immediately after the function entry point.
53 void ARMException::BeginFunction(const MachineFunction *MF) {
54   Asm->OutStreamer.EmitFnStart();
55   if (!Asm->MF->getFunction()->doesNotThrow() || UnwindTablesMandatory)
56     Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_begin",
57                                                   Asm->getFunctionNumber()));
58 }
59 
60 /// EndFunction - Gather and emit post-function exception information.
61 ///
62 void ARMException::EndFunction() {
63   if (Asm->MF->getFunction()->doesNotThrow() && !UnwindTablesMandatory)
64     Asm->OutStreamer.EmitCantUnwind();
65   else {
66     Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_end",
67                                                   Asm->getFunctionNumber()));
68 
69     // Emit references to personality.
70     if (const Function * Personality =
71         MMI->getPersonalities()[MMI->getPersonalityIndex()]) {
72       MCSymbol *PerSym = Asm->Mang->getSymbol(Personality);
73       Asm->OutStreamer.EmitSymbolAttribute(PerSym, MCSA_Global);
74       Asm->OutStreamer.EmitPersonality(PerSym);
75     }
76 
77     // Map all labels and get rid of any dead landing pads.
78     MMI->TidyLandingPads();
79 
80     Asm->OutStreamer.EmitHandlerData();
81 
82     // Emit actual exception table
83     EmitExceptionTable();
84   }
85 
86   Asm->OutStreamer.EmitFnEnd();
87 }
88