DwarfException.cpp [plain text]
#include "DwarfException.h"
#include "llvm/Module.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineLocation.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Target/Mangler.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetFrameInfo.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/Timer.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Twine.h"
using namespace llvm;
DwarfException::DwarfException(raw_ostream &OS, AsmPrinter *A,
const MCAsmInfo *T)
: DwarfPrinter(OS, A, T), shouldEmitTable(false),shouldEmitMoves(false),
shouldEmitTableModule(false), shouldEmitMovesModule(false),
ExceptionTimer(0) {
if (TimePassesIsEnabled)
ExceptionTimer = new Timer("DWARF Exception Writer");
}
DwarfException::~DwarfException() {
delete ExceptionTimer;
}
void DwarfException::EmitCIE(const Function *PersonalityFn, unsigned Index) {
int stackGrowth =
Asm->TM.getFrameInfo()->getStackGrowthDirection() ==
TargetFrameInfo::StackGrowsUp ?
TD->getPointerSize() : -TD->getPointerSize();
const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
Asm->OutStreamer.SwitchSection(TLOF.getEHFrameSection());
MCSymbol *EHFrameSym;
if (TLOF.isFunctionEHFrameSymbolPrivate())
EHFrameSym = getDWLabel("EH_frame", Index);
else
EHFrameSym = Asm->OutContext.GetOrCreateSymbol(Twine("EH_frame") +
Twine(Index));
Asm->OutStreamer.EmitLabel(EHFrameSym);
Asm->OutStreamer.EmitLabel(getDWLabel("section_eh_frame", Index));
Asm->OutStreamer.EmitLabel(getDWLabel("eh_frame_common", Index));
Asm->OutStreamer.AddComment("Length of Common Information Entry");
EmitDifference(getDWLabel("eh_frame_common_end", Index),
getDWLabel("eh_frame_common_begin", Index), true);
Asm->OutStreamer.EmitLabel(getDWLabel("eh_frame_common_begin", Index));
Asm->OutStreamer.AddComment("CIE Identifier Tag");
Asm->OutStreamer.EmitIntValue(0, 4, 0);
Asm->OutStreamer.AddComment("DW_CIE_VERSION");
Asm->OutStreamer.EmitIntValue(dwarf::DW_CIE_VERSION, 1, 0);
unsigned LSDAEncoding = TLOF.getLSDAEncoding();
unsigned FDEEncoding = TLOF.getFDEEncoding();
unsigned PerEncoding = TLOF.getPersonalityEncoding();
char Augmentation[6] = { 0 };
unsigned AugmentationSize = 0;
char *APtr = Augmentation + 1;
if (PersonalityFn) {
*APtr++ = 'P';
AugmentationSize += 1 + SizeOfEncodedValue(PerEncoding);
}
if (UsesLSDA[Index]) {
*APtr++ = 'L';
++AugmentationSize;
}
if (FDEEncoding != dwarf::DW_EH_PE_absptr) {
*APtr++ = 'R';
++AugmentationSize;
}
if (APtr != Augmentation + 1)
Augmentation[0] = 'z';
Asm->OutStreamer.AddComment("CIE Augmentation");
Asm->OutStreamer.EmitBytes(StringRef(Augmentation, strlen(Augmentation)+1),0);
EmitULEB128(1, "CIE Code Alignment Factor");
EmitSLEB128(stackGrowth, "CIE Data Alignment Factor");
Asm->OutStreamer.AddComment("CIE Return Address Column");
Asm->EmitInt8(RI->getDwarfRegNum(RI->getRARegister(), true));
if (Augmentation[0]) {
EmitULEB128(AugmentationSize, "Augmentation Size");
if (PersonalityFn) {
EmitEncodingByte(PerEncoding, "Personality");
Asm->OutStreamer.AddComment("Personality");
EmitReference(PersonalityFn, PerEncoding);
}
if (UsesLSDA[Index])
EmitEncodingByte(LSDAEncoding, "LSDA");
if (FDEEncoding != dwarf::DW_EH_PE_absptr)
EmitEncodingByte(FDEEncoding, "FDE");
}
std::vector<MachineMove> Moves;
RI->getInitialFrameState(Moves);
EmitFrameMoves(0, Moves, true);
Asm->EmitAlignment(TD->getPointerSize() == 4 ? 2 : 3, 0, 0, false);
Asm->OutStreamer.EmitLabel(getDWLabel("eh_frame_common_end", Index));
}
void DwarfException::EmitFDE(const FunctionEHFrameInfo &EHFrameInfo) {
assert(!EHFrameInfo.function->hasAvailableExternallyLinkage() &&
"Should not emit 'available externally' functions at all");
const Function *TheFunc = EHFrameInfo.function;
const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
unsigned LSDAEncoding = TLOF.getLSDAEncoding();
unsigned FDEEncoding = TLOF.getFDEEncoding();
Asm->OutStreamer.SwitchSection(TLOF.getEHFrameSection());
if (!TheFunc->hasLocalLinkage() && TLOF.isFunctionEHSymbolGlobal())
Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,MCSA_Global);
if (TheFunc->isWeakForLinker() && MAI->getWeakDefDirective())
Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
MCSA_WeakDefinition);
if (TheFunc->hasHiddenVisibility())
if (MCSymbolAttr HiddenAttr = MAI->getHiddenVisibilityAttr())
Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
HiddenAttr);
if (!EHFrameInfo.adjustsStack && !UnwindTablesMandatory &&
(!TheFunc->isWeakForLinker() ||
!MAI->getWeakDefDirective() ||
TLOF.getSupportsWeakOmittedEHFrame())) {
Asm->OutStreamer.EmitAssignment(EHFrameInfo.FunctionEHSym,
MCConstantExpr::Create(0, Asm->OutContext));
if (MAI->hasNoDeadStrip())
Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
MCSA_NoDeadStrip);
} else {
Asm->OutStreamer.EmitLabel(EHFrameInfo.FunctionEHSym);
Asm->OutStreamer.AddComment("Length of Frame Information Entry");
EmitDifference(getDWLabel("eh_frame_end", EHFrameInfo.Number),
getDWLabel("eh_frame_begin", EHFrameInfo.Number),
true);
Asm->OutStreamer.EmitLabel(getDWLabel("eh_frame_begin",EHFrameInfo.Number));
Asm->OutStreamer.AddComment("FDE CIE offset");
EmitSectionOffset(getDWLabel("eh_frame_begin", EHFrameInfo.Number),
getDWLabel("eh_frame_common",
EHFrameInfo.PersonalityIndex),
true, true);
MCSymbol *EHFuncBeginSym = getDWLabel("eh_func_begin", EHFrameInfo.Number);
Asm->OutStreamer.AddComment("FDE initial location");
EmitReference(EHFuncBeginSym, FDEEncoding);
Asm->OutStreamer.AddComment("FDE address range");
EmitDifference(getDWLabel("eh_func_end", EHFrameInfo.Number),EHFuncBeginSym,
SizeOfEncodedValue(FDEEncoding) == 4);
if (MMI->getPersonalities()[0] != NULL) {
unsigned Size = SizeOfEncodedValue(LSDAEncoding);
EmitULEB128(Size, "Augmentation size");
Asm->OutStreamer.AddComment("Language Specific Data Area");
if (EHFrameInfo.hasLandingPads)
EmitReference(getDWLabel("exception", EHFrameInfo.Number),LSDAEncoding);
else
Asm->OutStreamer.EmitIntValue(0, Size, 0);
} else {
EmitULEB128(0, "Augmentation size");
}
EmitFrameMoves(EHFuncBeginSym, EHFrameInfo.Moves, true);
Asm->EmitAlignment(TD->getPointerSize() == sizeof(int32_t) ? 2 : 3,
0, 0, false);
Asm->OutStreamer.EmitLabel(getDWLabel("eh_frame_end", EHFrameInfo.Number));
if (MMI->isUsedFunction(EHFrameInfo.function))
if (MAI->hasNoDeadStrip())
Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
MCSA_NoDeadStrip);
}
Asm->OutStreamer.AddBlankLine();
}
unsigned DwarfException::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;
}
bool DwarfException::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;
}
unsigned DwarfException::
ComputeActionsTable(const SmallVectorImpl<const LandingPadInfo*> &LandingPads,
SmallVectorImpl<ActionEntry> &Actions,
SmallVectorImpl<unsigned> &FirstActions) {
const std::vector<unsigned> &FilterIds = MMI->getFilterIds();
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);
}
FirstActions.reserve(LandingPads.size());
int FirstAction = 0;
unsigned SizeActions = 0;
const LandingPadInfo *PrevLPI = 0;
for (SmallVectorImpl<const LandingPadInfo *>::const_iterator
I = LandingPads.begin(), E = LandingPads.end(); I != E; ++I) {
const LandingPadInfo *LPI = *I;
const std::vector<int> &TypeIds = LPI->TypeIds;
const unsigned NumShared = PrevLPI ? SharedTypeIds(LPI, PrevLPI) : 0;
unsigned SizeSiteActions = 0;
if (NumShared < TypeIds.size()) {
unsigned SizeAction = 0;
unsigned PrevAction = (unsigned)-1;
if (NumShared) {
const unsigned SizePrevIds = PrevLPI->TypeIds.size();
assert(Actions.size());
PrevAction = Actions.size() - 1;
SizeAction =
MCAsmInfo::getSLEB128Size(Actions[PrevAction].NextAction) +
MCAsmInfo::getSLEB128Size(Actions[PrevAction].ValueForTypeID);
for (unsigned j = NumShared; j != SizePrevIds; ++j) {
assert(PrevAction != (unsigned)-1 && "PrevAction is invalid!");
SizeAction -=
MCAsmInfo::getSLEB128Size(Actions[PrevAction].ValueForTypeID);
SizeAction += -Actions[PrevAction].NextAction;
PrevAction = Actions[PrevAction].Previous;
}
}
for (unsigned J = NumShared, M = TypeIds.size(); J != M; ++J) {
int TypeID = TypeIds[J];
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.size() - 1;
}
FirstAction = SizeActions + SizeSiteActions - SizeAction + 1;
}
FirstActions.push_back(FirstAction);
SizeActions += SizeSiteActions;
PrevLPI = LPI;
}
return SizeActions;
}
bool DwarfException::CallToNoUnwindFunction(const MachineInstr *MI) {
assert(MI->getDesc().isCall() && "This should be a call instruction!");
bool MarkedNoUnwind = false;
bool SawFunc = false;
for (unsigned I = 0, E = MI->getNumOperands(); I != E; ++I) {
const MachineOperand &MO = MI->getOperand(I);
if (!MO.isGlobal()) continue;
Function *F = dyn_cast<Function>(MO.getGlobal());
if (F == 0) continue;
if (SawFunc) {
MarkedNoUnwind = false;
break;
}
MarkedNoUnwind = F->doesNotThrow();
SawFunc = true;
}
return MarkedNoUnwind;
}
void DwarfException::
ComputeCallSiteTable(SmallVectorImpl<CallSiteEntry> &CallSites,
const RangeMapType &PadMap,
const SmallVectorImpl<const LandingPadInfo *> &LandingPads,
const SmallVectorImpl<unsigned> &FirstActions) {
MCSymbol *LastLabel = 0;
bool SawPotentiallyThrowing = false;
bool PreviousIsInvoke = false;
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()) {
if (MI->getDesc().isCall())
SawPotentiallyThrowing |= !CallToNoUnwindFunction(MI);
continue;
}
MCSymbol *BeginLabel = MI->getOperand(0).getMCSymbol();
if (BeginLabel == LastLabel)
SawPotentiallyThrowing = false;
RangeMapType::const_iterator L = PadMap.find(BeginLabel);
if (L == PadMap.end())
continue;
const PadRange &P = L->second;
const LandingPadInfo *LandingPad = LandingPads[P.PadIndex];
assert(BeginLabel == LandingPad->BeginLabels[P.RangeIndex] &&
"Inconsistent landing pad map!");
if (SawPotentiallyThrowing &&
MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) {
CallSiteEntry Site = { LastLabel, BeginLabel, 0, 0 };
CallSites.push_back(Site);
PreviousIsInvoke = false;
}
LastLabel = LandingPad->EndLabels[P.RangeIndex];
assert(BeginLabel && LastLabel && "Invalid landing pad!");
if (!LandingPad->LandingPadLabel) {
PreviousIsInvoke = false;
} else {
CallSiteEntry Site = {
BeginLabel,
LastLabel,
LandingPad->LandingPadLabel,
FirstActions[P.PadIndex]
};
if (PreviousIsInvoke &&
MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) {
CallSiteEntry &Prev = CallSites.back();
if (Site.PadLabel == Prev.PadLabel && Site.Action == Prev.Action) {
Prev.EndLabel = Site.EndLabel;
continue;
}
}
if (MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf)
CallSites.push_back(Site);
else {
unsigned SiteNo = MMI->getCallSiteBeginLabel(BeginLabel);
if (CallSites.size() < SiteNo)
CallSites.resize(SiteNo);
CallSites[SiteNo - 1] = Site;
}
PreviousIsInvoke = true;
}
}
}
if (SawPotentiallyThrowing &&
MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) {
CallSiteEntry Site = { LastLabel, 0, 0, 0 };
CallSites.push_back(Site);
}
}
void DwarfException::EmitExceptionTable() {
const std::vector<GlobalVariable *> &TypeInfos = MMI->getTypeInfos();
const std::vector<unsigned> &FilterIds = MMI->getFilterIds();
const std::vector<LandingPadInfo> &PadInfos = MMI->getLandingPads();
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);
SmallVector<ActionEntry, 32> Actions;
SmallVector<unsigned, 64> FirstActions;
unsigned SizeActions=ComputeActionsTable(LandingPads, Actions, FirstActions);
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;
}
}
SmallVector<CallSiteEntry, 64> CallSites;
ComputeCallSiteTable(CallSites, PadMap, LandingPads, FirstActions);
const unsigned SiteStartSize = SizeOfEncodedValue(dwarf::DW_EH_PE_udata4);
const unsigned SiteLengthSize = SizeOfEncodedValue(dwarf::DW_EH_PE_udata4);
const unsigned LandingPadSize = SizeOfEncodedValue(dwarf::DW_EH_PE_udata4);
bool IsSJLJ = MAI->getExceptionHandlingType() == ExceptionHandling::SjLj;
bool HaveTTData = IsSJLJ ? (!TypeInfos.empty() || !FilterIds.empty()) : true;
unsigned CallSiteTableLength;
if (IsSJLJ)
CallSiteTableLength = 0;
else
CallSiteTableLength = CallSites.size() *
(SiteStartSize + SiteLengthSize + LandingPadSize);
for (unsigned i = 0, e = CallSites.size(); i < e; ++i) {
CallSiteTableLength += MCAsmInfo::getULEB128Size(CallSites[i].Action);
if (IsSJLJ)
CallSiteTableLength += MCAsmInfo::getULEB128Size(i);
}
const MCSection *LSDASection = Asm->getObjFileLowering().getLSDASection();
unsigned TTypeEncoding;
unsigned TypeFormatSize;
if (!HaveTTData) {
TTypeEncoding = dwarf::DW_EH_PE_omit;
TypeFormatSize = SizeOfEncodedValue(dwarf::DW_EH_PE_absptr);
} else {
TTypeEncoding = Asm->getObjFileLowering().getTTypeEncoding();
TypeFormatSize = SizeOfEncodedValue(TTypeEncoding);
}
Asm->OutStreamer.SwitchSection(LSDASection);
Asm->EmitAlignment(2, 0, 0, false);
MCSymbol *GCCETSym =
Asm->OutContext.GetOrCreateSymbol(Twine("GCC_except_table")+
Twine(SubprogramCount));
Asm->OutStreamer.EmitLabel(GCCETSym);
Asm->OutStreamer.EmitLabel(getDWLabel("exception", SubprogramCount));
if (IsSJLJ)
Asm->OutStreamer.EmitLabel(getDWLabel("_LSDA_", Asm->getFunctionNumber()));
EmitEncodingByte(dwarf::DW_EH_PE_omit, "@LPStart");
EmitEncodingByte(TTypeEncoding, "@TType");
unsigned SizeTypes = TypeInfos.size() * TypeFormatSize;
unsigned CallSiteTableLengthSize =
MCAsmInfo::getULEB128Size(CallSiteTableLength);
unsigned TTypeBaseOffset =
sizeof(int8_t) + CallSiteTableLengthSize + CallSiteTableLength + SizeActions + SizeTypes;
unsigned TTypeBaseOffsetSize = MCAsmInfo::getULEB128Size(TTypeBaseOffset);
unsigned TotalSize =
sizeof(int8_t) + sizeof(int8_t) + (HaveTTData ? TTypeBaseOffsetSize : 0) + TTypeBaseOffset; unsigned SizeAlign = (4 - TotalSize) & 3;
if (HaveTTData) {
EmitULEB128(TTypeBaseOffset, "@TType base offset", SizeAlign);
SizeAlign = 0;
}
if (IsSJLJ) {
EmitEncodingByte(dwarf::DW_EH_PE_udata4, "Call site");
EmitULEB128(CallSiteTableLength, "Call site table length", SizeAlign);
unsigned idx = 0;
for (SmallVectorImpl<CallSiteEntry>::const_iterator
I = CallSites.begin(), E = CallSites.end(); I != E; ++I, ++idx) {
const CallSiteEntry &S = *I;
EmitULEB128(idx, "Landing pad");
EmitULEB128(S.Action, "Action");
}
} else {
assert(MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf);
EmitEncodingByte(dwarf::DW_EH_PE_udata4, "Call site");
EmitULEB128(CallSiteTableLength, "Call site table length", SizeAlign);
for (SmallVectorImpl<CallSiteEntry>::const_iterator
I = CallSites.begin(), E = CallSites.end(); I != E; ++I) {
const CallSiteEntry &S = *I;
MCSymbol *EHFuncBeginSym = getDWLabel("eh_func_begin", SubprogramCount);
MCSymbol *BeginLabel = S.BeginLabel;
if (BeginLabel == 0)
BeginLabel = EHFuncBeginSym;
MCSymbol *EndLabel = S.EndLabel;
if (EndLabel == 0)
EndLabel = getDWLabel("eh_func_end", SubprogramCount);
Asm->OutStreamer.AddComment("Region start");
EmitSectionOffset(BeginLabel, EHFuncBeginSym, true, true);
Asm->OutStreamer.AddComment("Region length");
EmitDifference(EndLabel, BeginLabel, true);
Asm->OutStreamer.AddComment("Landing pad");
if (!S.PadLabel)
Asm->OutStreamer.EmitIntValue(0, 4, 0);
else
EmitSectionOffset(S.PadLabel, EHFuncBeginSym, true, true);
EmitULEB128(S.Action, "Action");
}
}
if (Actions.size() != 0) {
Asm->OutStreamer.AddComment("-- Action Record Table --");
Asm->OutStreamer.AddBlankLine();
}
for (SmallVectorImpl<ActionEntry>::const_iterator
I = Actions.begin(), E = Actions.end(); I != E; ++I) {
const ActionEntry &Action = *I;
Asm->OutStreamer.AddComment("Action Record");
Asm->OutStreamer.AddBlankLine();
EmitSLEB128(Action.ValueForTypeID, " TypeInfo index");
EmitSLEB128(Action.NextAction, " Next action");
}
if (!TypeInfos.empty()) {
Asm->OutStreamer.AddComment("-- Catch TypeInfos --");
Asm->OutStreamer.AddBlankLine();
}
for (std::vector<GlobalVariable *>::const_reverse_iterator
I = TypeInfos.rbegin(), E = TypeInfos.rend(); I != E; ++I) {
const GlobalVariable *GV = *I;
Asm->OutStreamer.AddComment("TypeInfo");
if (GV)
EmitReference(GV, TTypeEncoding);
else
Asm->OutStreamer.EmitIntValue(0, SizeOfEncodedValue(TTypeEncoding), 0);
}
if (!FilterIds.empty()) {
Asm->OutStreamer.AddComment("-- Filter IDs --");
Asm->OutStreamer.AddBlankLine();
}
for (std::vector<unsigned>::const_iterator
I = FilterIds.begin(), E = FilterIds.end(); I < E; ++I) {
unsigned TypeID = *I;
EmitULEB128(TypeID, TypeID != 0 ? "Exception specification" : 0);
}
Asm->EmitAlignment(2, 0, 0, false);
}
void DwarfException::EndModule() {
if (MAI->getExceptionHandlingType() != ExceptionHandling::Dwarf)
return;
if (!shouldEmitMovesModule && !shouldEmitTableModule)
return;
if (TimePassesIsEnabled)
ExceptionTimer->startTimer();
const std::vector<Function *> Personalities = MMI->getPersonalities();
for (unsigned I = 0, E = Personalities.size(); I < E; ++I)
EmitCIE(Personalities[I], I);
for (std::vector<FunctionEHFrameInfo>::iterator
I = EHFrames.begin(), E = EHFrames.end(); I != E; ++I)
EmitFDE(*I);
if (TimePassesIsEnabled)
ExceptionTimer->stopTimer();
}
void DwarfException::BeginFunction(const MachineFunction *MF) {
if (!MMI || !MAI->doesSupportExceptionHandling()) return;
if (TimePassesIsEnabled)
ExceptionTimer->startTimer();
this->MF = MF;
shouldEmitTable = shouldEmitMoves = false;
shouldEmitTable = !MMI->getLandingPads().empty();
shouldEmitMoves = !MF->getFunction()->doesNotThrow() || UnwindTablesMandatory;
if (shouldEmitMoves || shouldEmitTable)
Asm->OutStreamer.EmitLabel(getDWLabel("eh_func_begin", ++SubprogramCount));
shouldEmitTableModule |= shouldEmitTable;
shouldEmitMovesModule |= shouldEmitMoves;
if (TimePassesIsEnabled)
ExceptionTimer->stopTimer();
}
void DwarfException::EndFunction() {
if (!shouldEmitMoves && !shouldEmitTable) return;
if (TimePassesIsEnabled)
ExceptionTimer->startTimer();
Asm->OutStreamer.EmitLabel(getDWLabel("eh_func_end", SubprogramCount));
bool HasLandingPad = !MMI->getLandingPads().empty();
UsesLSDA[MMI->getPersonalityIndex()] |= HasLandingPad;
MMI->TidyLandingPads();
if (HasLandingPad)
EmitExceptionTable();
const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
MCSymbol *FunctionEHSym =
Asm->GetSymbolWithGlobalValueBase(MF->getFunction(), ".eh",
TLOF.isFunctionEHFrameSymbolPrivate());
EHFrames.push_back(FunctionEHFrameInfo(FunctionEHSym, SubprogramCount,
MMI->getPersonalityIndex(),
MF->getFrameInfo()->adjustsStack(),
!MMI->getLandingPads().empty(),
MMI->getFrameMoves(),
MF->getFunction()));
if (TimePassesIsEnabled)
ExceptionTimer->stopTimer();
}