1 //===-- CodeGen/AsmPrinter/DwarfException.cpp - Dwarf Exception Impl ------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains support for writing dwarf exception info into asm files.
12 //===----------------------------------------------------------------------===//
14 #include "DwarfException.h"
15 #include "llvm/Module.h"
16 #include "llvm/CodeGen/MachineModuleInfo.h"
17 #include "llvm/CodeGen/MachineFrameInfo.h"
18 #include "llvm/CodeGen/MachineLocation.h"
19 #include "llvm/Support/Dwarf.h"
20 #include "llvm/Support/Timer.h"
21 #include "llvm/Support/raw_ostream.h"
22 #include "llvm/Target/TargetAsmInfo.h"
23 #include "llvm/Target/TargetRegisterInfo.h"
24 #include "llvm/Target/TargetData.h"
25 #include "llvm/Target/TargetFrameInfo.h"
26 #include "llvm/Target/TargetOptions.h"
27 #include "llvm/ADT/StringExtras.h"
30 static TimerGroup &getDwarfTimerGroup() {
31 static TimerGroup DwarfTimerGroup("Dwarf Exception");
32 return DwarfTimerGroup;
35 DwarfException::DwarfException(raw_ostream &OS, AsmPrinter *A,
36 const TargetAsmInfo *T)
37 : Dwarf(OS, A, T, "eh"), shouldEmitTable(false), shouldEmitMoves(false),
38 shouldEmitTableModule(false), shouldEmitMovesModule(false),
40 if (TimePassesIsEnabled)
41 ExceptionTimer = new Timer("Dwarf Exception Writer",
42 getDwarfTimerGroup());
45 DwarfException::~DwarfException() {
46 delete ExceptionTimer;
49 void DwarfException::EmitCommonEHFrame(const Function *Personality,
51 // Size and sign of stack growth.
53 Asm->TM.getFrameInfo()->getStackGrowthDirection() ==
54 TargetFrameInfo::StackGrowsUp ?
55 TD->getPointerSize() : -TD->getPointerSize();
57 // Begin eh frame section.
58 Asm->SwitchToTextSection(TAI->getDwarfEHFrameSection());
60 if (TAI->is_EHSymbolPrivate())
61 O << TAI->getPrivateGlobalPrefix();
63 O << "EH_frame" << Index << ":\n";
64 EmitLabel("section_eh_frame", Index);
66 // Define base labels.
67 EmitLabel("eh_frame_common", Index);
69 // Define the eh frame length.
70 EmitDifference("eh_frame_common_end", Index,
71 "eh_frame_common_begin", Index, true);
72 Asm->EOL("Length of Common Information Entry");
75 EmitLabel("eh_frame_common_begin", Index);
76 Asm->EmitInt32((int)0);
77 Asm->EOL("CIE Identifier Tag");
78 Asm->EmitInt8(dwarf::DW_CIE_VERSION);
79 Asm->EOL("CIE Version");
81 // The personality presence indicates that language specific information will
82 // show up in the eh frame.
83 Asm->EmitString(Personality ? "zPLR" : "zR");
84 Asm->EOL("CIE Augmentation");
87 Asm->EmitULEB128Bytes(1);
88 Asm->EOL("CIE Code Alignment Factor");
89 Asm->EmitSLEB128Bytes(stackGrowth);
90 Asm->EOL("CIE Data Alignment Factor");
91 Asm->EmitInt8(RI->getDwarfRegNum(RI->getRARegister(), true));
92 Asm->EOL("CIE Return Address Column");
94 // If there is a personality, we need to indicate the functions location.
96 Asm->EmitULEB128Bytes(7);
97 Asm->EOL("Augmentation Size");
99 if (TAI->getNeedsIndirectEncoding()) {
100 Asm->EmitInt8(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4 |
101 dwarf::DW_EH_PE_indirect);
102 Asm->EOL("Personality (pcrel sdata4 indirect)");
104 Asm->EmitInt8(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4);
105 Asm->EOL("Personality (pcrel sdata4)");
108 PrintRelDirective(true);
109 O << TAI->getPersonalityPrefix();
110 Asm->EmitExternalGlobal((const GlobalVariable *)(Personality));
111 O << TAI->getPersonalitySuffix();
112 if (strcmp(TAI->getPersonalitySuffix(), "+4@GOTPCREL"))
113 O << "-" << TAI->getPCSymbol();
114 Asm->EOL("Personality");
116 Asm->EmitInt8(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4);
117 Asm->EOL("LSDA Encoding (pcrel sdata4)");
119 Asm->EmitInt8(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4);
120 Asm->EOL("FDE Encoding (pcrel sdata4)");
122 Asm->EmitULEB128Bytes(1);
123 Asm->EOL("Augmentation Size");
125 Asm->EmitInt8(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4);
126 Asm->EOL("FDE Encoding (pcrel sdata4)");
129 // Indicate locations of general callee saved registers in frame.
130 std::vector<MachineMove> Moves;
131 RI->getInitialFrameState(Moves);
132 EmitFrameMoves(NULL, 0, Moves, true);
134 // On Darwin the linker honors the alignment of eh_frame, which means it must
135 // be 8-byte on 64-bit targets to match what gcc does. Otherwise you get
136 // holes which confuse readers of eh_frame.
137 Asm->EmitAlignment(TD->getPointerSize() == sizeof(int32_t) ? 2 : 3,
139 EmitLabel("eh_frame_common_end", Index);
144 /// EmitEHFrame - Emit function exception frame information.
146 void DwarfException::EmitEHFrame(const FunctionEHFrameInfo &EHFrameInfo) {
147 assert(!EHFrameInfo.function->hasAvailableExternallyLinkage() &&
148 "Should not emit 'available externally' functions at all");
150 Function::LinkageTypes linkage = EHFrameInfo.function->getLinkage();
151 Asm->SwitchToTextSection(TAI->getDwarfEHFrameSection());
153 // Externally visible entry into the functions eh frame info. If the
154 // corresponding function is static, this should not be externally visible.
155 if (linkage != Function::InternalLinkage &&
156 linkage != Function::PrivateLinkage) {
157 if (const char *GlobalEHDirective = TAI->getGlobalEHDirective())
158 O << GlobalEHDirective << EHFrameInfo.FnName << "\n";
161 // If corresponding function is weak definition, this should be too.
162 if ((linkage == Function::WeakAnyLinkage ||
163 linkage == Function::WeakODRLinkage ||
164 linkage == Function::LinkOnceAnyLinkage ||
165 linkage == Function::LinkOnceODRLinkage) &&
166 TAI->getWeakDefDirective())
167 O << TAI->getWeakDefDirective() << EHFrameInfo.FnName << "\n";
169 // If there are no calls then you can't unwind. This may mean we can omit the
170 // EH Frame, but some environments do not handle weak absolute symbols. If
171 // UnwindTablesMandatory is set we cannot do this optimization; the unwind
172 // info is to be available for non-EH uses.
173 if (!EHFrameInfo.hasCalls &&
174 !UnwindTablesMandatory &&
175 ((linkage != Function::WeakAnyLinkage &&
176 linkage != Function::WeakODRLinkage &&
177 linkage != Function::LinkOnceAnyLinkage &&
178 linkage != Function::LinkOnceODRLinkage) ||
179 !TAI->getWeakDefDirective() ||
180 TAI->getSupportsWeakOmittedEHFrame())) {
181 O << EHFrameInfo.FnName << " = 0\n";
182 // This name has no connection to the function, so it might get
183 // dead-stripped when the function is not, erroneously. Prohibit
184 // dead-stripping unconditionally.
185 if (const char *UsedDirective = TAI->getUsedDirective())
186 O << UsedDirective << EHFrameInfo.FnName << "\n\n";
188 O << EHFrameInfo.FnName << ":\n";
191 EmitDifference("eh_frame_end", EHFrameInfo.Number,
192 "eh_frame_begin", EHFrameInfo.Number, true);
193 Asm->EOL("Length of Frame Information Entry");
195 EmitLabel("eh_frame_begin", EHFrameInfo.Number);
197 if (!TAI->is_EHSymbolPrivate()) {
198 // FIXME: HOW ARE THESE TWO ARMS DIFFERENT?? EH_frame vs eh_frame_common?
199 PrintRelDirective(true, true);
200 PrintLabelName("eh_frame_begin", EHFrameInfo.Number);
202 if (!TAI->isAbsoluteEHSectionOffsets())
203 O << "-EH_frame" << EHFrameInfo.PersonalityIndex;
205 EmitSectionOffset("eh_frame_begin", "eh_frame_common",
206 EHFrameInfo.Number, EHFrameInfo.PersonalityIndex,
210 Asm->EOL("FDE CIE offset");
212 EmitReference("eh_func_begin", EHFrameInfo.Number, true, true);
213 Asm->EOL("FDE initial location");
214 EmitDifference("eh_func_end", EHFrameInfo.Number,
215 "eh_func_begin", EHFrameInfo.Number, true);
216 Asm->EOL("FDE address range");
218 // If there is a personality and landing pads then point to the language
219 // specific data area in the exception table.
220 if (EHFrameInfo.PersonalityIndex) {
221 Asm->EmitULEB128Bytes(4);
222 Asm->EOL("Augmentation size");
224 if (EHFrameInfo.hasLandingPads)
225 EmitReference("exception", EHFrameInfo.Number, true, true);
227 Asm->EmitInt32((int)0);
228 Asm->EOL("Language Specific Data Area");
230 Asm->EmitULEB128Bytes(0);
231 Asm->EOL("Augmentation size");
234 // Indicate locations of function specific callee saved registers in frame.
235 EmitFrameMoves("eh_func_begin", EHFrameInfo.Number, EHFrameInfo.Moves,
238 // On Darwin the linker honors the alignment of eh_frame, which means it
239 // must be 8-byte on 64-bit targets to match what gcc does. Otherwise you
240 // get holes which confuse readers of eh_frame.
241 Asm->EmitAlignment(TD->getPointerSize() == sizeof(int32_t) ? 2 : 3,
243 EmitLabel("eh_frame_end", EHFrameInfo.Number);
245 // If the function is marked used, this table should be also. We cannot
246 // make the mark unconditional in this case, since retaining the table also
247 // retains the function in this case, and there is code around that depends
248 // on unused functions (calling undefined externals) being dead-stripped to
249 // link correctly. Yes, there really is.
250 if (MMI->getUsedFunctions().count(EHFrameInfo.function))
251 if (const char *UsedDirective = TAI->getUsedDirective())
252 O << UsedDirective << EHFrameInfo.FnName << "\n\n";
256 /// EmitExceptionTable - Emit landing pads and actions.
258 /// The general organization of the table is complex, but the basic concepts are
259 /// easy. First there is a header which describes the location and organization
260 /// of the three components that follow.
262 /// 1. The landing pad site information describes the range of code covered by
263 /// the try. In our case it's an accumulation of the ranges covered by the
264 /// invokes in the try. There is also a reference to the landing pad that
265 /// handles the exception once processed. Finally an index into the actions
267 /// 2. The action table, in our case, is composed of pairs of type ids and next
268 /// action offset. Starting with the action index from the landing pad
269 /// site, each type Id is checked for a match to the current exception. If
270 /// it matches then the exception and type id are passed on to the landing
271 /// pad. Otherwise the next action is looked up. This chain is terminated
272 /// with a next action of zero. If no type id is found the the frame is
273 /// unwound and handling continues.
274 /// 3. Type id table contains references to all the C++ typeinfo for all
275 /// catches in the function. This tables is reversed indexed base 1.
277 /// SharedTypeIds - How many leading type ids two landing pads have in common.
278 unsigned DwarfException::SharedTypeIds(const LandingPadInfo *L,
279 const LandingPadInfo *R) {
280 const std::vector<int> &LIds = L->TypeIds, &RIds = R->TypeIds;
281 unsigned LSize = LIds.size(), RSize = RIds.size();
282 unsigned MinSize = LSize < RSize ? LSize : RSize;
285 for (; Count != MinSize; ++Count)
286 if (LIds[Count] != RIds[Count])
292 /// PadLT - Order landing pads lexicographically by type id.
293 bool DwarfException::PadLT(const LandingPadInfo *L, const LandingPadInfo *R) {
294 const std::vector<int> &LIds = L->TypeIds, &RIds = R->TypeIds;
295 unsigned LSize = LIds.size(), RSize = RIds.size();
296 unsigned MinSize = LSize < RSize ? LSize : RSize;
298 for (unsigned i = 0; i != MinSize; ++i)
299 if (LIds[i] != RIds[i])
300 return LIds[i] < RIds[i];
302 return LSize < RSize;
305 void DwarfException::EmitExceptionTable() {
306 const std::vector<GlobalVariable *> &TypeInfos = MMI->getTypeInfos();
307 const std::vector<unsigned> &FilterIds = MMI->getFilterIds();
308 const std::vector<LandingPadInfo> &PadInfos = MMI->getLandingPads();
309 if (PadInfos.empty()) return;
311 // Sort the landing pads in order of their type ids. This is used to fold
312 // duplicate actions.
313 SmallVector<const LandingPadInfo *, 64> LandingPads;
314 LandingPads.reserve(PadInfos.size());
315 for (unsigned i = 0, N = PadInfos.size(); i != N; ++i)
316 LandingPads.push_back(&PadInfos[i]);
317 std::sort(LandingPads.begin(), LandingPads.end(), PadLT);
319 // Negative type ids index into FilterIds, positive type ids index into
320 // TypeInfos. The value written for a positive type id is just the type id
321 // itself. For a negative type id, however, the value written is the
322 // (negative) byte offset of the corresponding FilterIds entry. The byte
323 // offset is usually equal to the type id, because the FilterIds entries are
324 // written using a variable width encoding which outputs one byte per entry as
325 // long as the value written is not too large, but can differ. This kind of
326 // complication does not occur for positive type ids because type infos are
327 // output using a fixed width encoding. FilterOffsets[i] holds the byte
328 // offset corresponding to FilterIds[i].
329 SmallVector<int, 16> FilterOffsets;
330 FilterOffsets.reserve(FilterIds.size());
332 for(std::vector<unsigned>::const_iterator I = FilterIds.begin(),
333 E = FilterIds.end(); I != E; ++I) {
334 FilterOffsets.push_back(Offset);
335 Offset -= TargetAsmInfo::getULEB128Size(*I);
338 // Compute the actions table and gather the first action index for each
340 SmallVector<ActionEntry, 32> Actions;
341 SmallVector<unsigned, 64> FirstActions;
342 FirstActions.reserve(LandingPads.size());
345 unsigned SizeActions = 0;
346 for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) {
347 const LandingPadInfo *LP = LandingPads[i];
348 const std::vector<int> &TypeIds = LP->TypeIds;
349 const unsigned NumShared = i ? SharedTypeIds(LP, LandingPads[i-1]) : 0;
350 unsigned SizeSiteActions = 0;
352 if (NumShared < TypeIds.size()) {
353 unsigned SizeAction = 0;
354 ActionEntry *PrevAction = 0;
357 const unsigned SizePrevIds = LandingPads[i-1]->TypeIds.size();
358 assert(Actions.size());
359 PrevAction = &Actions.back();
360 SizeAction = TargetAsmInfo::getSLEB128Size(PrevAction->NextAction) +
361 TargetAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
363 for (unsigned j = NumShared; j != SizePrevIds; ++j) {
365 TargetAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
366 SizeAction += -PrevAction->NextAction;
367 PrevAction = PrevAction->Previous;
371 // Compute the actions.
372 for (unsigned I = NumShared, M = TypeIds.size(); I != M; ++I) {
373 int TypeID = TypeIds[I];
374 assert(-1-TypeID < (int)FilterOffsets.size() && "Unknown filter id!");
375 int ValueForTypeID = TypeID < 0 ? FilterOffsets[-1 - TypeID] : TypeID;
376 unsigned SizeTypeID = TargetAsmInfo::getSLEB128Size(ValueForTypeID);
378 int NextAction = SizeAction ? -(SizeAction + SizeTypeID) : 0;
379 SizeAction = SizeTypeID + TargetAsmInfo::getSLEB128Size(NextAction);
380 SizeSiteActions += SizeAction;
382 ActionEntry Action = {ValueForTypeID, NextAction, PrevAction};
383 Actions.push_back(Action);
385 PrevAction = &Actions.back();
388 // Record the first action of the landing pad site.
389 FirstAction = SizeActions + SizeSiteActions - SizeAction + 1;
390 } // else identical - re-use previous FirstAction
392 FirstActions.push_back(FirstAction);
394 // Compute this sites contribution to size.
395 SizeActions += SizeSiteActions;
398 // Compute the call-site table. The entry for an invoke has a try-range
399 // containing the call, a non-zero landing pad and an appropriate action. The
400 // entry for an ordinary call has a try-range containing the call and zero for
401 // the landing pad and the action. Calls marked 'nounwind' have no entry and
402 // must not be contained in the try-range of any entry - they form gaps in the
403 // table. Entries must be ordered by try-range address.
404 SmallVector<CallSiteEntry, 64> CallSites;
408 // Invokes and nounwind calls have entries in PadMap (due to being bracketed
409 // by try-range labels when lowered). Ordinary calls do not, so appropriate
410 // try-ranges for them need be deduced.
411 for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) {
412 const LandingPadInfo *LandingPad = LandingPads[i];
413 for (unsigned j = 0, E = LandingPad->BeginLabels.size(); j != E; ++j) {
414 unsigned BeginLabel = LandingPad->BeginLabels[j];
415 assert(!PadMap.count(BeginLabel) && "Duplicate landing pad labels!");
416 PadRange P = { i, j };
417 PadMap[BeginLabel] = P;
421 // The end label of the previous invoke or nounwind try-range.
422 unsigned LastLabel = 0;
424 // Whether there is a potentially throwing instruction (currently this means
425 // an ordinary call) between the end of the previous try-range and now.
426 bool SawPotentiallyThrowing = false;
428 // Whether the last callsite entry was for an invoke.
429 bool PreviousIsInvoke = false;
431 // Visit all instructions in order of address.
432 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
434 for (MachineBasicBlock::const_iterator MI = I->begin(), E = I->end();
436 if (!MI->isLabel()) {
437 SawPotentiallyThrowing |= MI->getDesc().isCall();
441 unsigned BeginLabel = MI->getOperand(0).getImm();
442 assert(BeginLabel && "Invalid label!");
444 // End of the previous try-range?
445 if (BeginLabel == LastLabel)
446 SawPotentiallyThrowing = false;
448 // Beginning of a new try-range?
449 RangeMapType::iterator L = PadMap.find(BeginLabel);
450 if (L == PadMap.end())
451 // Nope, it was just some random label.
454 PadRange P = L->second;
455 const LandingPadInfo *LandingPad = LandingPads[P.PadIndex];
457 assert(BeginLabel == LandingPad->BeginLabels[P.RangeIndex] &&
458 "Inconsistent landing pad map!");
460 // If some instruction between the previous try-range and this one may
461 // throw, create a call-site entry with no landing pad for the region
462 // between the try-ranges.
463 if (SawPotentiallyThrowing) {
464 CallSiteEntry Site = {LastLabel, BeginLabel, 0, 0};
465 CallSites.push_back(Site);
466 PreviousIsInvoke = false;
469 LastLabel = LandingPad->EndLabels[P.RangeIndex];
470 assert(BeginLabel && LastLabel && "Invalid landing pad!");
472 if (LandingPad->LandingPadLabel) {
473 // This try-range is for an invoke.
474 CallSiteEntry Site = {BeginLabel, LastLabel,
475 LandingPad->LandingPadLabel,
476 FirstActions[P.PadIndex]};
478 // Try to merge with the previous call-site.
479 if (PreviousIsInvoke) {
480 CallSiteEntry &Prev = CallSites.back();
481 if (Site.PadLabel == Prev.PadLabel && Site.Action == Prev.Action) {
482 // Extend the range of the previous entry.
483 Prev.EndLabel = Site.EndLabel;
488 // Otherwise, create a new call-site.
489 CallSites.push_back(Site);
490 PreviousIsInvoke = true;
493 PreviousIsInvoke = false;
498 // If some instruction between the previous try-range and the end of the
499 // function may throw, create a call-site entry with no landing pad for the
500 // region following the try-range.
501 if (SawPotentiallyThrowing) {
502 CallSiteEntry Site = {LastLabel, 0, 0, 0};
503 CallSites.push_back(Site);
509 const unsigned SiteStartSize = sizeof(int32_t); // DW_EH_PE_udata4
510 const unsigned SiteLengthSize = sizeof(int32_t); // DW_EH_PE_udata4
511 const unsigned LandingPadSize = sizeof(int32_t); // DW_EH_PE_udata4
512 unsigned SizeSites = CallSites.size() * (SiteStartSize +
515 for (unsigned i = 0, e = CallSites.size(); i < e; ++i)
516 SizeSites += TargetAsmInfo::getULEB128Size(CallSites[i].Action);
519 const unsigned TypeInfoSize = TD->getPointerSize(); // DW_EH_PE_absptr
520 unsigned SizeTypes = TypeInfos.size() * TypeInfoSize;
522 unsigned TypeOffset = sizeof(int8_t) + // Call site format
523 TargetAsmInfo::getULEB128Size(SizeSites) + // Call-site table length
524 SizeSites + SizeActions + SizeTypes;
526 unsigned TotalSize = sizeof(int8_t) + // LPStart format
527 sizeof(int8_t) + // TType format
528 TargetAsmInfo::getULEB128Size(TypeOffset) + // TType base offset
531 unsigned SizeAlign = (4 - TotalSize) & 3;
533 // Begin the exception table.
534 Asm->SwitchToDataSection(TAI->getDwarfExceptionSection());
535 Asm->EmitAlignment(2, 0, 0, false);
536 O << "GCC_except_table" << SubprogramCount << ":\n";
538 for (unsigned i = 0; i != SizeAlign; ++i) {
543 EmitLabel("exception", SubprogramCount);
546 Asm->EmitInt8(dwarf::DW_EH_PE_omit);
547 Asm->EOL("LPStart format (DW_EH_PE_omit)");
548 Asm->EmitInt8(dwarf::DW_EH_PE_absptr);
549 Asm->EOL("TType format (DW_EH_PE_absptr)");
550 Asm->EmitULEB128Bytes(TypeOffset);
551 Asm->EOL("TType base offset");
552 Asm->EmitInt8(dwarf::DW_EH_PE_udata4);
553 Asm->EOL("Call site format (DW_EH_PE_udata4)");
554 Asm->EmitULEB128Bytes(SizeSites);
555 Asm->EOL("Call-site table length");
557 // Emit the landing pad site information.
558 for (unsigned i = 0; i < CallSites.size(); ++i) {
559 CallSiteEntry &S = CallSites[i];
560 const char *BeginTag;
561 unsigned BeginNumber;
564 BeginTag = "eh_func_begin";
565 BeginNumber = SubprogramCount;
568 BeginNumber = S.BeginLabel;
571 EmitSectionOffset(BeginTag, "eh_func_begin", BeginNumber, SubprogramCount,
573 Asm->EOL("Region start");
576 EmitDifference("eh_func_end", SubprogramCount, BeginTag, BeginNumber,
579 EmitDifference("label", S.EndLabel, BeginTag, BeginNumber, true);
581 Asm->EOL("Region length");
586 EmitSectionOffset("label", "eh_func_begin", S.PadLabel, SubprogramCount,
589 Asm->EOL("Landing pad");
591 Asm->EmitULEB128Bytes(S.Action);
596 for (unsigned I = 0, N = Actions.size(); I != N; ++I) {
597 ActionEntry &Action = Actions[I];
599 Asm->EmitSLEB128Bytes(Action.ValueForTypeID);
600 Asm->EOL("TypeInfo index");
601 Asm->EmitSLEB128Bytes(Action.NextAction);
602 Asm->EOL("Next action");
605 // Emit the type ids.
606 for (unsigned M = TypeInfos.size(); M; --M) {
607 GlobalVariable *GV = TypeInfos[M - 1];
612 O << Asm->getGlobalLinkName(GV, GLN);
617 Asm->EOL("TypeInfo");
620 // Emit the filter typeids.
621 for (unsigned j = 0, M = FilterIds.size(); j < M; ++j) {
622 unsigned TypeID = FilterIds[j];
623 Asm->EmitULEB128Bytes(TypeID);
624 Asm->EOL("Filter TypeInfo index");
627 Asm->EmitAlignment(2, 0, 0, false);
630 /// EndModule - Emit all exception information that should come after the
632 void DwarfException::EndModule() {
633 if (TimePassesIsEnabled)
634 ExceptionTimer->startTimer();
636 if (shouldEmitMovesModule || shouldEmitTableModule) {
637 const std::vector<Function *> Personalities = MMI->getPersonalities();
638 for (unsigned i = 0; i < Personalities.size(); ++i)
639 EmitCommonEHFrame(Personalities[i], i);
641 for (std::vector<FunctionEHFrameInfo>::iterator I = EHFrames.begin(),
642 E = EHFrames.end(); I != E; ++I)
646 if (TimePassesIsEnabled)
647 ExceptionTimer->stopTimer();
650 /// BeginFunction - Gather pre-function exception information. Assumes being
651 /// emitted immediately after the function entry point.
652 void DwarfException::BeginFunction(MachineFunction *MF) {
653 if (TimePassesIsEnabled)
654 ExceptionTimer->startTimer();
657 shouldEmitTable = shouldEmitMoves = false;
659 if (MMI && TAI->doesSupportExceptionHandling()) {
660 // Map all labels and get rid of any dead landing pads.
661 MMI->TidyLandingPads();
663 // If any landing pads survive, we need an EH table.
664 if (MMI->getLandingPads().size())
665 shouldEmitTable = true;
667 // See if we need frame move info.
668 if (!MF->getFunction()->doesNotThrow() || UnwindTablesMandatory)
669 shouldEmitMoves = true;
671 if (shouldEmitMoves || shouldEmitTable)
672 // Assumes in correct section after the entry point.
673 EmitLabel("eh_func_begin", ++SubprogramCount);
676 shouldEmitTableModule |= shouldEmitTable;
677 shouldEmitMovesModule |= shouldEmitMoves;
679 if (TimePassesIsEnabled)
680 ExceptionTimer->stopTimer();
683 /// EndFunction - Gather and emit post-function exception information.
685 void DwarfException::EndFunction() {
686 if (TimePassesIsEnabled)
687 ExceptionTimer->startTimer();
689 if (shouldEmitMoves || shouldEmitTable) {
690 EmitLabel("eh_func_end", SubprogramCount);
691 EmitExceptionTable();
693 // Save EH frame information
695 FunctionEHFrameInfo(getAsm()->getCurrentFunctionEHName(MF),
697 MMI->getPersonalityIndex(),
698 MF->getFrameInfo()->hasCalls(),
699 !MMI->getLandingPads().empty(),
700 MMI->getFrameMoves(),
704 if (TimePassesIsEnabled)
705 ExceptionTimer->stopTimer();