//===----------------------------------------------------------------------===//
#include "DwarfException.h"
-#include "llvm/Module.h"
-#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
-#include "llvm/CodeGen/MachineLocation.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/Mangler.h"
+#include "llvm/IR/Module.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/Support/Dwarf.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/FormattedStream.h"
+#include "llvm/Support/LEB128.h"
+#include "llvm/Target/TargetFrameLowering.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, "eh"), shouldEmitTable(false),shouldEmitMoves(false),
- shouldEmitTableModule(false), shouldEmitMovesModule(false),
- ExceptionTimer(0) {
- if (TimePassesIsEnabled)
- ExceptionTimer = new Timer("DWARF Exception Writer");
-}
-
-DwarfException::~DwarfException() {
- delete ExceptionTimer;
-}
-
-/// SizeOfEncodedValue - Return the size of the encoding in bytes.
-unsigned DwarfException::SizeOfEncodedValue(unsigned Encoding) {
- if (Encoding == dwarf::DW_EH_PE_omit)
- return 0;
-
- switch (Encoding & 0x07) {
- case dwarf::DW_EH_PE_absptr:
- return TD->getPointerSize();
- case dwarf::DW_EH_PE_udata2:
- return 2;
- case dwarf::DW_EH_PE_udata4:
- return 4;
- case dwarf::DW_EH_PE_udata8:
- return 8;
- }
-
- assert(0 && "Invalid encoded value.");
- return 0;
-}
-
-/// CreateLabelDiff - Emit a label and subtract it from the expression we
-/// already have. This is equivalent to emitting "foo - .", but we have to emit
-/// the label for "." directly.
-const MCExpr *DwarfException::CreateLabelDiff(const MCExpr *ExprRef,
- const char *LabelName,
- unsigned Index) {
- SmallString<64> Name;
- raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix()
- << LabelName << Asm->getFunctionNumber()
- << "_" << Index;
- MCSymbol *DotSym = Asm->OutContext.GetOrCreateSymbol(Name.str());
- Asm->OutStreamer.EmitLabel(DotSym);
-
- return MCBinaryExpr::CreateSub(ExprRef,
- MCSymbolRefExpr::Create(DotSym,
- Asm->OutContext),
- Asm->OutContext);
-}
-
-/// EmitCIE - Emit a Common Information Entry (CIE). This holds information that
-/// is shared among many Frame Description Entries. There is at least one CIE
-/// in every non-empty .debug_frame section.
-void DwarfException::EmitCIE(const Function *PersonalityFn, unsigned Index) {
- // Size and sign of stack growth.
- int stackGrowth =
- Asm->TM.getFrameInfo()->getStackGrowthDirection() ==
- TargetFrameInfo::StackGrowsUp ?
- TD->getPointerSize() : -TD->getPointerSize();
-
- const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
-
- // Begin eh frame section.
- Asm->OutStreamer.SwitchSection(TLOF.getEHFrameSection());
-
- if (MAI->is_EHSymbolPrivate())
- O << MAI->getPrivateGlobalPrefix();
- O << "EH_frame" << Index << ":\n";
-
- EmitLabel("section_eh_frame", Index);
-
- // Define base labels.
- EmitLabel("eh_frame_common", Index);
-
- // Define the eh frame length.
- EmitDifference("eh_frame_common_end", Index,
- "eh_frame_common_begin", Index, true);
- EOL("Length of Common Information Entry");
-
- // EH frame header.
- EmitLabel("eh_frame_common_begin", Index);
- if (Asm->VerboseAsm) Asm->OutStreamer.AddComment("CIE Identifier Tag");
- Asm->OutStreamer.EmitIntValue(0, 4/*size*/, 0/*addrspace*/);
- if (Asm->VerboseAsm) Asm->OutStreamer.AddComment("DW_CIE_VERSION");
- Asm->OutStreamer.EmitIntValue(dwarf::DW_CIE_VERSION, 1/*size*/, 0/*addr*/);
-
- // The personality presence indicates that language specific information will
- // show up in the eh frame. Find out how we are supposed to lower the
- // personality function reference:
- const MCExpr *PersonalityRef = 0;
- bool IsPersonalityIndirect = false, IsPersonalityPCRel = false;
- if (PersonalityFn) {
- // FIXME: HANDLE STATIC CODEGEN MODEL HERE.
-
- // In non-static mode, ask the object file how to represent this reference.
- PersonalityRef =
- TLOF.getSymbolForDwarfGlobalReference(PersonalityFn, Asm->Mang,
- Asm->MMI,
- IsPersonalityIndirect,
- IsPersonalityPCRel);
- }
-
- unsigned PerEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
- if (IsPersonalityIndirect)
- PerEncoding |= dwarf::DW_EH_PE_indirect;
- unsigned LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
- unsigned FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
-
- char Augmentation[6] = { 0 };
- unsigned AugmentationSize = 0;
- char *APtr = Augmentation + 1;
-
- if (PersonalityRef) {
- // There is a personality function.
- *APtr++ = 'P';
- AugmentationSize += 1 + SizeOfEncodedValue(PerEncoding);
- }
-
- if (UsesLSDA[Index]) {
- // An LSDA pointer is in the FDE augmentation.
- *APtr++ = 'L';
- ++AugmentationSize;
- }
-
- if (FDEEncoding != dwarf::DW_EH_PE_absptr) {
- // A non-default pointer encoding for the FDE.
- *APtr++ = 'R';
- ++AugmentationSize;
- }
-
- if (APtr != Augmentation + 1)
- Augmentation[0] = 'z';
-
- Asm->OutStreamer.EmitBytes(StringRef(Augmentation, strlen(Augmentation)+1),0);
- EOL("CIE Augmentation");
-
- // Round out reader.
- EmitULEB128(1, "CIE Code Alignment Factor");
- EmitSLEB128(stackGrowth, "CIE Data Alignment Factor");
- Asm->EmitInt8(RI->getDwarfRegNum(RI->getRARegister(), true));
- EOL("CIE Return Address Column");
-
- EmitULEB128(AugmentationSize, "Augmentation Size");
- EmitEncodingByte(PerEncoding, "Personality");
-
- // If there is a personality, we need to indicate the function's location.
- if (PersonalityRef) {
- if (!IsPersonalityPCRel)
- PersonalityRef = CreateLabelDiff(PersonalityRef, "personalityref_addr",
- Index);
-
- O << MAI->getData32bitsDirective() << *PersonalityRef;
- EOL("Personality");
+DwarfException::DwarfException(AsmPrinter *A)
+ : Asm(A), MMI(Asm->MMI) {}
- EmitEncodingByte(LSDAEncoding, "LSDA");
- EmitEncodingByte(FDEEncoding, "FDE");
- }
-
- // Indicate locations of general callee saved registers in frame.
- std::vector<MachineMove> Moves;
- RI->getInitialFrameState(Moves);
- EmitFrameMoves(NULL, 0, Moves, true);
-
- // On Darwin the linker honors the alignment of eh_frame, which means it must
- // be 8-byte on 64-bit targets to match what gcc does. Otherwise you get
- // holes which confuse readers of eh_frame.
- Asm->EmitAlignment(TD->getPointerSize() == 4 ? 2 : 3, 0, 0, false);
- EmitLabel("eh_frame_common_end", Index);
- Asm->O << '\n';
-}
-
-/// EmitFDE - Emit the Frame Description Entry (FDE) for the function.
-void DwarfException::EmitFDE(const FunctionEHFrameInfo &EHFrameInfo) {
- assert(!EHFrameInfo.function->hasAvailableExternallyLinkage() &&
- "Should not emit 'available externally' functions at all");
-
- const Function *TheFunc = EHFrameInfo.function;
-
- Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering().getEHFrameSection());
-
- // Externally visible entry into the functions eh frame info. If the
- // corresponding function is static, this should not be externally visible.
- if (!TheFunc->hasLocalLinkage())
- if (const char *GlobalEHDirective = MAI->getGlobalEHDirective())
- O << GlobalEHDirective << *EHFrameInfo.FunctionEHSym << '\n';
-
- // If corresponding function is weak definition, this should be too.
- if (TheFunc->isWeakForLinker() && MAI->getWeakDefDirective())
- O << MAI->getWeakDefDirective() << *EHFrameInfo.FunctionEHSym << '\n';
-
- // If corresponding function is hidden, this should be too.
- if (TheFunc->hasHiddenVisibility())
- if (MCSymbolAttr HiddenAttr = MAI->getHiddenVisibilityAttr())
- Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
- HiddenAttr);
-
- // If there are no calls then you can't unwind. This may mean we can omit the
- // EH Frame, but some environments do not handle weak absolute symbols. If
- // UnwindTablesMandatory is set we cannot do this optimization; the unwind
- // info is to be available for non-EH uses.
- if (!EHFrameInfo.hasCalls && !UnwindTablesMandatory &&
- (!TheFunc->isWeakForLinker() ||
- !MAI->getWeakDefDirective() ||
- MAI->getSupportsWeakOmittedEHFrame())) {
- O << *EHFrameInfo.FunctionEHSym << " = 0\n";
- // This name has no connection to the function, so it might get
- // dead-stripped when the function is not, erroneously. Prohibit
- // dead-stripping unconditionally.
- if (MAI->hasNoDeadStrip())
- Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
- MCSA_NoDeadStrip);
- } else {
- O << *EHFrameInfo.FunctionEHSym << ":\n";
-
- // EH frame header.
- EmitDifference("eh_frame_end", EHFrameInfo.Number,
- "eh_frame_begin", EHFrameInfo.Number, true);
- EOL("Length of Frame Information Entry");
-
- EmitLabel("eh_frame_begin", EHFrameInfo.Number);
-
- EmitSectionOffset("eh_frame_begin", "eh_frame_common",
- EHFrameInfo.Number, EHFrameInfo.PersonalityIndex,
- true, true, false);
-
- EOL("FDE CIE offset");
-
- EmitReference("eh_func_begin", EHFrameInfo.Number, true, true);
- EOL("FDE initial location");
- EmitDifference("eh_func_end", EHFrameInfo.Number,
- "eh_func_begin", EHFrameInfo.Number, true);
- EOL("FDE address range");
-
- // If there is a personality and landing pads then point to the language
- // specific data area in the exception table.
- if (MMI->getPersonalities()[0] != NULL) {
-
- if (Asm->TM.getLSDAEncoding() != DwarfLSDAEncoding::EightByte) {
- EmitULEB128(4, "Augmentation size");
-
- if (EHFrameInfo.hasLandingPads)
- EmitReference("exception", EHFrameInfo.Number, true, true);
- else
- Asm->OutStreamer.EmitIntValue(0, 4/*size*/, 0/*addrspace*/);
- } else {
- EmitULEB128(TD->getPointerSize(), "Augmentation size");
-
- if (EHFrameInfo.hasLandingPads) {
- EmitReference("exception", EHFrameInfo.Number, true, false);
- } else {
- Asm->OutStreamer.EmitIntValue(0, TD->getPointerSize(),
- 0/*addrspace*/);
- }
- }
-
- EOL("Language Specific Data Area");
- } else {
- EmitULEB128(0, "Augmentation size");
- }
-
- // Indicate locations of function specific callee saved registers in frame.
- EmitFrameMoves("eh_func_begin", EHFrameInfo.Number, EHFrameInfo.Moves,
- true);
-
- // On Darwin the linker honors the alignment of eh_frame, which means it
- // must be 8-byte on 64-bit targets to match what gcc does. Otherwise you
- // get holes which confuse readers of eh_frame.
- Asm->EmitAlignment(TD->getPointerSize() == sizeof(int32_t) ? 2 : 3,
- 0, 0, false);
- EmitLabel("eh_frame_end", EHFrameInfo.Number);
-
- // If the function is marked used, this table should be also. We cannot
- // make the mark unconditional in this case, since retaining the table also
- // retains the function in this case, and there is code around that depends
- // on unused functions (calling undefined externals) being dead-stripped to
- // link correctly. Yes, there really is.
- if (MMI->isUsedFunction(EHFrameInfo.function))
- if (MAI->hasNoDeadStrip())
- Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
- MCSA_NoDeadStrip);
- }
- Asm->O << '\n';
-}
+DwarfException::~DwarfException() {}
/// SharedTypeIds - How many leading type ids two landing pads have in common.
unsigned DwarfException::SharedTypeIds(const LandingPadInfo *L,
return Count;
}
-/// PadLT - Order landing pads lexicographically by type id.
-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;
-}
-
/// ComputeActionsTable - Compute the actions table and gather the first action
/// index for each landing pad site.
unsigned DwarfException::
for (std::vector<unsigned>::const_iterator
I = FilterIds.begin(), E = FilterIds.end(); I != E; ++I) {
FilterOffsets.push_back(Offset);
- Offset -= MCAsmInfo::getULEB128Size(*I);
+ Offset -= getULEB128Size(*I);
}
FirstActions.reserve(LandingPads.size());
int FirstAction = 0;
unsigned SizeActions = 0;
- const LandingPadInfo *PrevLPI = 0;
+ const LandingPadInfo *PrevLPI = nullptr;
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 NumShared = PrevLPI ? SharedTypeIds(LPI, PrevLPI) : 0;
unsigned SizeSiteActions = 0;
if (NumShared < TypeIds.size()) {
unsigned SizeAction = 0;
- ActionEntry *PrevAction = 0;
+ unsigned PrevAction = (unsigned)-1;
if (NumShared) {
- const unsigned SizePrevIds = PrevLPI->TypeIds.size();
+ unsigned SizePrevIds = PrevLPI->TypeIds.size();
assert(Actions.size());
- PrevAction = &Actions.back();
- SizeAction = MCAsmInfo::getSLEB128Size(PrevAction->NextAction) +
- MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
+ PrevAction = Actions.size() - 1;
+ SizeAction = getSLEB128Size(Actions[PrevAction].NextAction) +
+ getSLEB128Size(Actions[PrevAction].ValueForTypeID);
for (unsigned j = NumShared; j != SizePrevIds; ++j) {
- SizeAction -=
- MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
- SizeAction += -PrevAction->NextAction;
- PrevAction = PrevAction->Previous;
+ assert(PrevAction != (unsigned)-1 && "PrevAction is invalid!");
+ SizeAction -= getSLEB128Size(Actions[PrevAction].ValueForTypeID);
+ SizeAction += -Actions[PrevAction].NextAction;
+ PrevAction = Actions[PrevAction].Previous;
}
}
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);
+ unsigned SizeTypeID = getSLEB128Size(ValueForTypeID);
int NextAction = SizeAction ? -(SizeAction + SizeTypeID) : 0;
- SizeAction = SizeTypeID + MCAsmInfo::getSLEB128Size(NextAction);
+ SizeAction = SizeTypeID + getSLEB128Size(NextAction);
SizeSiteActions += SizeAction;
ActionEntry Action = { ValueForTypeID, NextAction, PrevAction };
Actions.push_back(Action);
- PrevAction = &Actions.back();
+ PrevAction = Actions.size() - 1;
}
// Record the first action of the landing pad site.
// Information used when created the call-site table. The action record
// field of the call site record is the offset of the first associated
// action record, relative to the start of the actions table. This value is
- // biased by 1 (1 in dicating the start of the actions table), and 0
+ // biased by 1 (1 indicating the start of the actions table), and 0
// indicates that there are no actions.
FirstActions.push_back(FirstAction);
/// CallToNoUnwindFunction - Return `true' if this is a call to a function
/// marked `nounwind'. Return `false' otherwise.
bool DwarfException::CallToNoUnwindFunction(const MachineInstr *MI) {
- assert(MI->getDesc().isCall() && "This should be a call instruction!");
+ assert(MI->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()) {
- if (Function *F = dyn_cast<Function>(MO.getGlobal())) {
- if (SawFunc) {
- // Be conservative. If we have more than one function operand for this
- // call, then we can't make the assumption that it's the callee and
- // not a parameter to the call.
- //
- // FIXME: Determine if there's a way to say that `F' is the callee or
- // parameter.
- MarkedNoUnwind = false;
- break;
- }
+ if (!MO.isGlobal()) continue;
- MarkedNoUnwind = F->doesNotThrow();
- SawFunc = true;
- }
+ const Function *F = dyn_cast<Function>(MO.getGlobal());
+ if (!F) continue;
+
+ if (SawFunc) {
+ // Be conservative. If we have more than one function operand for this
+ // call, then we can't make the assumption that it's the callee and
+ // not a parameter to the call.
+ //
+ // FIXME: Determine if there's a way to say that `F' is the callee or
+ // parameter.
+ MarkedNoUnwind = false;
+ break;
}
+
+ MarkedNoUnwind = F->doesNotThrow();
+ SawFunc = true;
}
return MarkedNoUnwind;
const SmallVectorImpl<const LandingPadInfo *> &LandingPads,
const SmallVectorImpl<unsigned> &FirstActions) {
// The end label of the previous invoke or nounwind try-range.
- unsigned LastLabel = 0;
+ MCSymbol *LastLabel = nullptr;
// Whether there is a potentially throwing instruction (currently this means
// an ordinary call) between the end of the previous try-range and now.
bool PreviousIsInvoke = false;
// Visit all instructions in order of address.
- 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);
-
+ for (const auto &MBB : *Asm->MF) {
+ for (const auto &MI : MBB) {
+ if (!MI.isEHLabel()) {
+ if (MI.isCall())
+ SawPotentiallyThrowing |= !CallToNoUnwindFunction(&MI);
continue;
}
- unsigned BeginLabel = MI->getOperand(0).getImm();
- assert(BeginLabel && "Invalid label!");
-
// End of the previous try-range?
+ MCSymbol *BeginLabel = MI.getOperand(0).getMCSymbol();
if (BeginLabel == LastLabel)
SawPotentiallyThrowing = false;
// 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 (SawPotentiallyThrowing &&
- MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) {
- CallSiteEntry Site = { LastLabel, BeginLabel, 0, 0 };
+ if (SawPotentiallyThrowing && Asm->MAI->isExceptionHandlingDwarf()) {
+ CallSiteEntry Site = { LastLabel, BeginLabel, nullptr, 0 };
CallSites.push_back(Site);
PreviousIsInvoke = false;
}
LastLabel = LandingPad->EndLabels[P.RangeIndex];
assert(BeginLabel && LastLabel && "Invalid landing pad!");
- if (LandingPad->LandingPadLabel) {
+ if (!LandingPad->LandingPadLabel) {
+ // Create a gap.
+ PreviousIsInvoke = false;
+ } else {
// This try-range is for an invoke.
CallSiteEntry Site = {
BeginLabel,
};
// Try to merge with the previous call-site. SJLJ doesn't do this
- if (PreviousIsInvoke &&
- MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) {
+ if (PreviousIsInvoke && Asm->MAI->isExceptionHandlingDwarf()) {
CallSiteEntry &Prev = CallSites.back();
if (Site.PadLabel == Prev.PadLabel && Site.Action == Prev.Action) {
// Extend the range of the previous entry.
}
// Otherwise, create a new call-site.
- if (MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf)
+ if (Asm->MAI->isExceptionHandlingDwarf())
CallSites.push_back(Site);
else {
// SjLj EH must maintain the call sites in the order assigned
CallSites[SiteNo - 1] = Site;
}
PreviousIsInvoke = true;
- } else {
- // Create a gap.
- PreviousIsInvoke = false;
}
}
}
// 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 (SawPotentiallyThrowing &&
- MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) {
- CallSiteEntry Site = { LastLabel, 0, 0, 0 };
+ if (SawPotentiallyThrowing && Asm->MAI->isExceptionHandlingDwarf()) {
+ CallSiteEntry Site = { LastLabel, nullptr, nullptr, 0 };
CallSites.push_back(Site);
}
}
/// 3. Type ID table contains references to all the C++ typeinfo for all
/// catches in the function. This tables is reverse indexed base 1.
void DwarfException::EmitExceptionTable() {
- const std::vector<GlobalVariable *> &TypeInfos = MMI->getTypeInfos();
+ const std::vector<const GlobalVariable *> &TypeInfos = MMI->getTypeInfos();
const std::vector<unsigned> &FilterIds = MMI->getFilterIds();
const std::vector<LandingPadInfo> &PadInfos = MMI->getLandingPads();
- if (PadInfos.empty()) return;
// Sort the landing pads in order of their type ids. This is used to fold
// duplicate actions.
for (unsigned i = 0, N = PadInfos.size(); i != N; ++i)
LandingPads.push_back(&PadInfos[i]);
- std::sort(LandingPads.begin(), LandingPads.end(), PadLT);
+ // Order landing pads lexicographically by type id.
+ std::sort(LandingPads.begin(), LandingPads.end(),
+ [](const LandingPadInfo *L,
+ const LandingPadInfo *R) { return L->TypeIds < R->TypeIds; });
// Compute the actions table and gather the first action index for each
// landing pad site.
SmallVector<ActionEntry, 32> Actions;
SmallVector<unsigned, 64> FirstActions;
- unsigned SizeActions = ComputeActionsTable(LandingPads, Actions,
- FirstActions);
+ unsigned SizeActions=ComputeActionsTable(LandingPads, Actions, FirstActions);
// Invokes and nounwind calls have entries in PadMap (due to being bracketed
// by try-range labels when lowered). Ordinary calls do not, so appropriate
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];
+ MCSymbol *BeginLabel = LandingPad->BeginLabels[j];
assert(!PadMap.count(BeginLabel) && "Duplicate landing pad labels!");
PadRange P = { i, j };
PadMap[BeginLabel] = P;
// Final tallies.
// Call sites.
- 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 IsSJLJ = Asm->MAI->getExceptionHandlingType() == ExceptionHandling::SjLj;
bool HaveTTData = IsSJLJ ? (!TypeInfos.empty() || !FilterIds.empty()) : true;
- unsigned SizeSites;
+ unsigned CallSiteTableLength;
if (IsSJLJ)
- SizeSites = 0;
- else
- SizeSites = CallSites.size() *
- (SiteStartSize + SiteLengthSize + LandingPadSize);
+ CallSiteTableLength = 0;
+ else {
+ unsigned SiteStartSize = 4; // dwarf::DW_EH_PE_udata4
+ unsigned SiteLengthSize = 4; // dwarf::DW_EH_PE_udata4
+ unsigned LandingPadSize = 4; // dwarf::DW_EH_PE_udata4
+ CallSiteTableLength =
+ CallSites.size() * (SiteStartSize + SiteLengthSize + LandingPadSize);
+ }
for (unsigned i = 0, e = CallSites.size(); i < e; ++i) {
- SizeSites += MCAsmInfo::getULEB128Size(CallSites[i].Action);
+ CallSiteTableLength += getULEB128Size(CallSites[i].Action);
if (IsSJLJ)
- SizeSites += MCAsmInfo::getULEB128Size(i);
+ CallSiteTableLength += getULEB128Size(i);
}
// Type infos.
const MCSection *LSDASection = Asm->getObjFileLowering().getLSDASection();
- unsigned TTypeFormat;
+ unsigned TTypeEncoding;
unsigned TypeFormatSize;
if (!HaveTTData) {
// For SjLj exceptions, if there is no TypeInfo, then we just explicitly say
// that we're omitting that bit.
- TTypeFormat = dwarf::DW_EH_PE_omit;
- TypeFormatSize = SizeOfEncodedValue(dwarf::DW_EH_PE_absptr);
+ TTypeEncoding = dwarf::DW_EH_PE_omit;
+ // dwarf::DW_EH_PE_absptr
+ TypeFormatSize = Asm->getDataLayout().getPointerSize();
} else {
// Okay, we have actual filters or typeinfos to emit. As such, we need to
// pick a type encoding for them. We're about to emit a list of pointers to
// mode, this reference will require a relocation by the dynamic linker.
//
// Because of this, we have a couple of options:
- //
+ //
// 1) If we are in -static mode, we can always use an absolute reference
// from the LSDA, because the static linker will resolve it.
- //
+ //
// 2) Otherwise, if the LSDA section is writable, we can output the direct
// reference to the typeinfo and allow the dynamic linker to relocate
// it. Since it is in a writable section, the dynamic linker won't
// have a problem.
- //
+ //
// 3) Finally, if we're in PIC mode and the LDSA section isn't writable,
// we need to use some form of indirection. For example, on Darwin,
// we can output a statically-relocatable reference to a dyld stub. The
// somewhere. This predicate should be moved to a shared location that is
// in target-independent code.
//
- if (LSDASection->getKind().isWriteable() ||
- Asm->TM.getRelocationModel() == Reloc::Static)
- TTypeFormat = dwarf::DW_EH_PE_absptr;
- else
- TTypeFormat = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
- dwarf::DW_EH_PE_sdata4;
-
- TypeFormatSize = SizeOfEncodedValue(TTypeFormat);
+ TTypeEncoding = Asm->getObjFileLowering().getTTypeEncoding();
+ TypeFormatSize = Asm->GetSizeOfEncodedValue(TTypeEncoding);
}
// Begin the exception table.
- Asm->OutStreamer.SwitchSection(LSDASection);
- Asm->EmitAlignment(2, 0, 0, false);
+ // Sometimes we want not to emit the data into separate section (e.g. ARM
+ // EHABI). In this case LSDASection will be NULL.
+ if (LSDASection)
+ Asm->OutStreamer.SwitchSection(LSDASection);
+ Asm->EmitAlignment(2);
+
+ // Emit the LSDA.
+ MCSymbol *GCCETSym =
+ Asm->OutContext.GetOrCreateSymbol(Twine("GCC_except_table")+
+ Twine(Asm->getFunctionNumber()));
+ Asm->OutStreamer.EmitLabel(GCCETSym);
+ Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("exception",
+ Asm->getFunctionNumber()));
+
+ if (IsSJLJ)
+ Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("_LSDA_",
+ Asm->getFunctionNumber()));
- O << "GCC_except_table" << SubprogramCount << ":\n";
+ // Emit the LSDA header.
+ Asm->EmitEncodingByte(dwarf::DW_EH_PE_omit, "@LPStart");
+ Asm->EmitEncodingByte(TTypeEncoding, "@TType");
// The type infos need to be aligned. GCC does this by inserting padding just
// before the type infos. However, this changes the size of the exception
// So by increasing the size by inserting padding, you may increase the number
// of bytes used for writing the size. If it increases, say by one byte, then
// you now need to output one less byte of padding to get the type infos
- // aligned. However this decreases the size of the exception table. This
+ // aligned. However this decreases the size of the exception table. This
// changes the value you have to output for the exception table size. Due to
// the variable length encoding, the number of bytes used for writing the
// length may decrease. If so, you then have to increase the amount of
// We chose another solution: don't output padding inside the table like GCC
// does, instead output it before the table.
unsigned SizeTypes = TypeInfos.size() * TypeFormatSize;
- unsigned TyOffset = sizeof(int8_t) + // Call site format
- MCAsmInfo::getULEB128Size(SizeSites) + // Call-site table length
- SizeSites + SizeActions + SizeTypes;
- unsigned TotalSize = sizeof(int8_t) + // LPStart format
- sizeof(int8_t) + // TType format
- (HaveTTData ?
- MCAsmInfo::getULEB128Size(TyOffset) : 0) + // TType base offset
- TyOffset;
+ unsigned CallSiteTableLengthSize = getULEB128Size(CallSiteTableLength);
+ unsigned TTypeBaseOffset =
+ sizeof(int8_t) + // Call site format
+ CallSiteTableLengthSize + // Call site table length size
+ CallSiteTableLength + // Call site table length
+ SizeActions + // Actions size
+ SizeTypes;
+ unsigned TTypeBaseOffsetSize = getULEB128Size(TTypeBaseOffset);
+ unsigned TotalSize =
+ sizeof(int8_t) + // LPStart format
+ sizeof(int8_t) + // TType format
+ (HaveTTData ? TTypeBaseOffsetSize : 0) + // TType base offset size
+ TTypeBaseOffset; // TType base offset
unsigned SizeAlign = (4 - TotalSize) & 3;
- for (unsigned i = 0; i != SizeAlign; ++i) {
- Asm->EmitInt8(0);
- EOL("Padding");
- }
-
- EmitLabel("exception", SubprogramCount);
-
- if (IsSJLJ) {
- SmallString<16> LSDAName;
- raw_svector_ostream(LSDAName) << MAI->getPrivateGlobalPrefix() <<
- "_LSDA_" << Asm->getFunctionNumber();
- O << LSDAName.str() << ":\n";
+ if (HaveTTData) {
+ // Account for any extra padding that will be added to the call site table
+ // length.
+ Asm->EmitULEB128(TTypeBaseOffset, "@TType base offset", SizeAlign);
+ SizeAlign = 0;
}
- // Emit the header.
- EmitEncodingByte(dwarf::DW_EH_PE_omit, "@LPStart");
- EmitEncodingByte(TTypeFormat, "@TType");
-
- if (HaveTTData)
- EmitULEB128(TyOffset, "@TType base offset");
+ bool VerboseAsm = Asm->OutStreamer.isVerboseAsm();
// SjLj Exception handling
if (IsSJLJ) {
- EmitEncodingByte(dwarf::DW_EH_PE_udata4, "Call site");
- EmitULEB128(SizeSites, "Call site table length");
+ Asm->EmitEncodingByte(dwarf::DW_EH_PE_udata4, "Call site");
+
+ // Add extra padding if it wasn't added to the TType base offset.
+ Asm->EmitULEB128(CallSiteTableLength, "Call site table length", SizeAlign);
// Emit the landing pad site information.
unsigned idx = 0;
// Offset of the landing pad, counted in 16-byte bundles relative to the
// @LPStart address.
- EmitULEB128(idx, "Landing pad");
+ if (VerboseAsm) {
+ Asm->OutStreamer.AddComment(">> Call Site " + Twine(idx) + " <<");
+ Asm->OutStreamer.AddComment(" On exception at call site "+Twine(idx));
+ }
+ Asm->EmitULEB128(idx);
// Offset of the first associated action record, relative to the start of
// the action table. This value is biased by 1 (1 indicates the start of
// the action table), and 0 indicates that there are no actions.
- EmitULEB128(S.Action, "Action");
+ if (VerboseAsm) {
+ if (S.Action == 0)
+ Asm->OutStreamer.AddComment(" Action: cleanup");
+ else
+ Asm->OutStreamer.AddComment(" Action: " +
+ Twine((S.Action - 1) / 2 + 1));
+ }
+ Asm->EmitULEB128(S.Action);
}
} else {
// DWARF Exception handling
- assert(MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf);
+ assert(Asm->MAI->isExceptionHandlingDwarf());
// The call-site table is a list of all call sites that may throw an
// exception (including C++ 'throw' statements) in the procedure
// supposed to throw.
// Emit the landing pad call site table.
- EmitEncodingByte(dwarf::DW_EH_PE_udata4, "Call site");
- EmitULEB128(SizeSites, "Call site table size");
+ Asm->EmitEncodingByte(dwarf::DW_EH_PE_udata4, "Call site");
+
+ // Add extra padding if it wasn't added to the TType base offset.
+ Asm->EmitULEB128(CallSiteTableLength, "Call site table length", SizeAlign);
+ unsigned Entry = 0;
for (SmallVectorImpl<CallSiteEntry>::const_iterator
I = CallSites.begin(), E = CallSites.end(); I != E; ++I) {
const CallSiteEntry &S = *I;
- const char *BeginTag;
- unsigned BeginNumber;
- if (!S.BeginLabel) {
- BeginTag = "eh_func_begin";
- BeginNumber = SubprogramCount;
- } else {
- BeginTag = "label";
- BeginNumber = S.BeginLabel;
- }
+ MCSymbol *EHFuncBeginSym =
+ Asm->GetTempSymbol("eh_func_begin", Asm->getFunctionNumber());
+
+ MCSymbol *BeginLabel = S.BeginLabel;
+ if (!BeginLabel)
+ BeginLabel = EHFuncBeginSym;
+ MCSymbol *EndLabel = S.EndLabel;
+ if (!EndLabel)
+ EndLabel = Asm->GetTempSymbol("eh_func_end", Asm->getFunctionNumber());
+
// Offset of the call site relative to the previous call site, counted in
// number of 16-byte bundles. The first call site is counted relative to
// the start of the procedure fragment.
- EmitSectionOffset(BeginTag, "eh_func_begin", BeginNumber, SubprogramCount,
- true, true);
- EOL("Region start");
-
- if (!S.EndLabel)
- EmitDifference("eh_func_end", SubprogramCount, BeginTag, BeginNumber,
- true);
- else
- EmitDifference("label", S.EndLabel, BeginTag, BeginNumber, true);
-
- EOL("Region length");
+ if (VerboseAsm)
+ Asm->OutStreamer.AddComment(">> Call Site " + Twine(++Entry) + " <<");
+ Asm->EmitLabelDifference(BeginLabel, EHFuncBeginSym, 4);
+ if (VerboseAsm)
+ Asm->OutStreamer.AddComment(Twine(" Call between ") +
+ BeginLabel->getName() + " and " +
+ EndLabel->getName());
+ Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
// Offset of the landing pad, counted in 16-byte bundles relative to the
// @LPStart address.
if (!S.PadLabel) {
- Asm->OutStreamer.AddComment("Landing pad");
- Asm->OutStreamer.EmitIntValue(0, 4/*size*/, 0/*addrspace*/);
+ if (VerboseAsm)
+ Asm->OutStreamer.AddComment(" has no landing pad");
+ Asm->OutStreamer.EmitIntValue(0, 4/*size*/);
} else {
- EmitSectionOffset("label", "eh_func_begin", S.PadLabel, SubprogramCount,
- true, true);
- EOL("Landing pad");
+ if (VerboseAsm)
+ Asm->OutStreamer.AddComment(Twine(" jumps to ") +
+ S.PadLabel->getName());
+ Asm->EmitLabelDifference(S.PadLabel, EHFuncBeginSym, 4);
}
// Offset of the first associated action record, relative to the start of
// the action table. This value is biased by 1 (1 indicates the start of
// the action table), and 0 indicates that there are no actions.
- EmitULEB128(S.Action, "Action");
+ if (VerboseAsm) {
+ if (S.Action == 0)
+ Asm->OutStreamer.AddComment(" On action: cleanup");
+ else
+ Asm->OutStreamer.AddComment(" On action: " +
+ Twine((S.Action - 1) / 2 + 1));
+ }
+ Asm->EmitULEB128(S.Action);
}
}
// Emit the Action Table.
- EOL("Action Record Table:");
- unsigned Iter = 1;
+ int Entry = 0;
for (SmallVectorImpl<ActionEntry>::const_iterator
I = Actions.begin(), E = Actions.end(); I != E; ++I) {
const ActionEntry &Action = *I;
- EOL(Twine("Action Record ") + Twine(Iter++));
+
+ if (VerboseAsm) {
+ // Emit comments that decode the action table.
+ Asm->OutStreamer.AddComment(">> Action Record " + Twine(++Entry) + " <<");
+ }
// Type Filter
//
// Used by the runtime to match the type of the thrown exception to the
// type of the catch clauses or the types in the exception specification.
- EmitSLEB128(Action.ValueForTypeID, " TypeInfo index");
+ if (VerboseAsm) {
+ if (Action.ValueForTypeID > 0)
+ Asm->OutStreamer.AddComment(" Catch TypeInfo " +
+ Twine(Action.ValueForTypeID));
+ else if (Action.ValueForTypeID < 0)
+ Asm->OutStreamer.AddComment(" Filter TypeInfo " +
+ Twine(Action.ValueForTypeID));
+ else
+ Asm->OutStreamer.AddComment(" Cleanup");
+ }
+ Asm->EmitSLEB128(Action.ValueForTypeID);
// Action Record
//
// Self-relative signed displacement in bytes of the next action record,
// or 0 if there is no next action record.
- EmitSLEB128(Action.NextAction, " Next action");
+ if (VerboseAsm) {
+ if (Action.NextAction == 0) {
+ Asm->OutStreamer.AddComment(" No further actions");
+ } else {
+ unsigned NextAction = Entry + (Action.NextAction + 1) / 2;
+ Asm->OutStreamer.AddComment(" Continue to action "+Twine(NextAction));
+ }
+ }
+ Asm->EmitSLEB128(Action.NextAction);
}
+ EmitTypeInfos(TTypeEncoding);
+
+ Asm->EmitAlignment(2);
+}
+
+void DwarfException::EmitTypeInfos(unsigned TTypeEncoding) {
+ const std::vector<const GlobalVariable *> &TypeInfos = MMI->getTypeInfos();
+ const std::vector<unsigned> &FilterIds = MMI->getFilterIds();
+
+ bool VerboseAsm = Asm->OutStreamer.isVerboseAsm();
+
+ int Entry = 0;
// Emit the Catch TypeInfos.
- Iter = TypeInfos.size();
- for (std::vector<GlobalVariable *>::const_reverse_iterator
+ if (VerboseAsm && !TypeInfos.empty()) {
+ Asm->OutStreamer.AddComment(">> Catch TypeInfos <<");
+ Asm->OutStreamer.AddBlankLine();
+ Entry = TypeInfos.size();
+ }
+
+ for (std::vector<const GlobalVariable *>::const_reverse_iterator
I = TypeInfos.rbegin(), E = TypeInfos.rend(); I != E; ++I) {
const GlobalVariable *GV = *I;
- PrintRelDirective();
-
- if (GV) {
- O << *Asm->GetGlobalValueSymbol(GV);
- EOL(Twine("TypeInfo ") + Twine(Iter--));
- } else {
- O << "0x0";
- EOL("");
- }
+ if (VerboseAsm)
+ Asm->OutStreamer.AddComment("TypeInfo " + Twine(Entry--));
+ Asm->EmitTTypeReference(GV, TTypeEncoding);
}
// Emit the Exception Specifications.
+ if (VerboseAsm && !FilterIds.empty()) {
+ Asm->OutStreamer.AddComment(">> Filter TypeInfos <<");
+ Asm->OutStreamer.AddBlankLine();
+ Entry = 0;
+ }
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);
- }
+ if (VerboseAsm) {
+ --Entry;
+ if (TypeID != 0)
+ Asm->OutStreamer.AddComment("FilterInfo " + Twine(Entry));
+ }
- Asm->EmitAlignment(2, 0, 0, false);
+ Asm->EmitULEB128(TypeID);
+ }
}
-/// EndModule - Emit all exception information that should come after the
+/// endModule - Emit all exception information that should come after the
/// content.
-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::endModule() {
+ llvm_unreachable("Should be implemented");
}
-/// BeginFunction - Gather pre-function exception information. Assumes it's
+/// beginFunction - Gather pre-function exception information. Assumes it's
/// being emitted immediately after the function entry point.
-void DwarfException::BeginFunction(const MachineFunction *MF) {
- if (!MMI || !MAI->doesSupportExceptionHandling()) return;
-
- if (TimePassesIsEnabled)
- ExceptionTimer->startTimer();
-
- this->MF = MF;
- shouldEmitTable = shouldEmitMoves = false;
-
- // Map all labels and get rid of any dead landing pads.
- MMI->TidyLandingPads();
-
- // If any landing pads survive, we need an EH table.
- if (!MMI->getLandingPads().empty())
- shouldEmitTable = true;
-
- // See if we need frame move info.
- if (!MF->getFunction()->doesNotThrow() || UnwindTablesMandatory)
- shouldEmitMoves = true;
-
- if (shouldEmitMoves || shouldEmitTable)
- // Assumes in correct section after the entry point.
- EmitLabel("eh_func_begin", ++SubprogramCount);
-
- shouldEmitTableModule |= shouldEmitTable;
- shouldEmitMovesModule |= shouldEmitMoves;
-
- if (TimePassesIsEnabled)
- ExceptionTimer->stopTimer();
+void DwarfException::beginFunction(const MachineFunction *MF) {
+ llvm_unreachable("Should be implemented");
}
-/// EndFunction - Gather and emit post-function exception information.
-///
-void DwarfException::EndFunction() {
- if (!shouldEmitMoves && !shouldEmitTable) return;
-
- if (TimePassesIsEnabled)
- ExceptionTimer->startTimer();
-
- EmitLabel("eh_func_end", SubprogramCount);
- EmitExceptionTable();
-
- MCSymbol *FunctionEHSym =
- Asm->GetSymbolWithGlobalValueBase(MF->getFunction(), ".eh",
- Asm->MAI->is_EHSymbolPrivate());
-
- // Save EH frame information
- EHFrames.push_back(FunctionEHFrameInfo(FunctionEHSym, SubprogramCount,
- MMI->getPersonalityIndex(),
- MF->getFrameInfo()->hasCalls(),
- !MMI->getLandingPads().empty(),
- MMI->getFrameMoves(),
- MF->getFunction()));
-
- // Record if this personality index uses a landing pad.
- UsesLSDA[MMI->getPersonalityIndex()] |= !MMI->getLandingPads().empty();
-
- if (TimePassesIsEnabled)
- ExceptionTimer->stopTimer();
+/// endFunction - Gather and emit post-function exception information.
+void DwarfException::endFunction(const MachineFunction *) {
+ llvm_unreachable("Should be implemented");
}