1 //===----- JITDwarfEmitter.cpp - Write dwarf tables into memory -----------===//
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 defines a JITDwarfEmitter object that is used by the JIT to
11 // write dwarf tables to memory.
13 //===----------------------------------------------------------------------===//
16 #include "JITDwarfEmitter.h"
17 #include "llvm/Function.h"
18 #include "llvm/ADT/DenseMap.h"
19 #include "llvm/CodeGen/JITCodeEmitter.h"
20 #include "llvm/CodeGen/MachineFunction.h"
21 #include "llvm/CodeGen/MachineLocation.h"
22 #include "llvm/CodeGen/MachineModuleInfo.h"
23 #include "llvm/ExecutionEngine/JITMemoryManager.h"
24 #include "llvm/Support/ErrorHandling.h"
25 #include "llvm/MC/MCAsmInfo.h"
26 #include "llvm/Target/TargetData.h"
27 #include "llvm/Target/TargetInstrInfo.h"
28 #include "llvm/Target/TargetFrameInfo.h"
29 #include "llvm/Target/TargetMachine.h"
30 #include "llvm/Target/TargetRegisterInfo.h"
33 JITDwarfEmitter::JITDwarfEmitter(JIT& theJit) : MMI(0), Jit(theJit) {}
36 unsigned char* JITDwarfEmitter::EmitDwarfTable(MachineFunction& F,
38 unsigned char* StartFunction,
39 unsigned char* EndFunction,
40 unsigned char* &EHFramePtr) {
41 assert(MMI && "MachineModuleInfo not registered!");
43 const TargetMachine& TM = F.getTarget();
44 TD = TM.getTargetData();
45 stackGrowthDirection = TM.getFrameInfo()->getStackGrowthDirection();
46 RI = TM.getRegisterInfo();
49 unsigned char* ExceptionTable = EmitExceptionTable(&F, StartFunction,
52 unsigned char* Result = 0;
54 const std::vector<Function *> Personalities = MMI->getPersonalities();
55 EHFramePtr = EmitCommonEHFrame(Personalities[MMI->getPersonalityIndex()]);
57 Result = EmitEHFrame(Personalities[MMI->getPersonalityIndex()], EHFramePtr,
58 StartFunction, EndFunction, ExceptionTable);
65 JITDwarfEmitter::EmitFrameMoves(intptr_t BaseLabelPtr,
66 const std::vector<MachineMove> &Moves) const {
67 unsigned PointerSize = TD->getPointerSize();
68 int stackGrowth = stackGrowthDirection == TargetFrameInfo::StackGrowsUp ?
69 PointerSize : -PointerSize;
71 unsigned BaseLabelID = 0;
73 for (unsigned i = 0, N = Moves.size(); i < N; ++i) {
74 const MachineMove &Move = Moves[i];
75 unsigned LabelID = Move.getLabelID();
78 LabelID = MMI->MappedLabel(LabelID);
80 // Throw out move if the label is invalid.
81 if (!LabelID) continue;
84 intptr_t LabelPtr = 0;
85 if (LabelID) LabelPtr = JCE->getLabelAddress(LabelID);
87 const MachineLocation &Dst = Move.getDestination();
88 const MachineLocation &Src = Move.getSource();
90 // Advance row if new location.
91 if (BaseLabelPtr && LabelID && (BaseLabelID != LabelID || !IsLocal)) {
92 JCE->emitByte(dwarf::DW_CFA_advance_loc4);
93 JCE->emitInt32(LabelPtr - BaseLabelPtr);
95 BaseLabelID = LabelID;
96 BaseLabelPtr = LabelPtr;
101 if (Dst.isReg() && Dst.getReg() == MachineLocation::VirtualFP) {
103 if (Src.getReg() == MachineLocation::VirtualFP) {
104 JCE->emitByte(dwarf::DW_CFA_def_cfa_offset);
106 JCE->emitByte(dwarf::DW_CFA_def_cfa);
107 JCE->emitULEB128Bytes(RI->getDwarfRegNum(Src.getReg(), true));
110 JCE->emitULEB128Bytes(-Src.getOffset());
112 llvm_unreachable("Machine move not supported yet.");
114 } else if (Src.isReg() &&
115 Src.getReg() == MachineLocation::VirtualFP) {
117 JCE->emitByte(dwarf::DW_CFA_def_cfa_register);
118 JCE->emitULEB128Bytes(RI->getDwarfRegNum(Dst.getReg(), true));
120 llvm_unreachable("Machine move not supported yet.");
123 unsigned Reg = RI->getDwarfRegNum(Src.getReg(), true);
124 int Offset = Dst.getOffset() / stackGrowth;
127 JCE->emitByte(dwarf::DW_CFA_offset_extended_sf);
128 JCE->emitULEB128Bytes(Reg);
129 JCE->emitSLEB128Bytes(Offset);
130 } else if (Reg < 64) {
131 JCE->emitByte(dwarf::DW_CFA_offset + Reg);
132 JCE->emitULEB128Bytes(Offset);
134 JCE->emitByte(dwarf::DW_CFA_offset_extended);
135 JCE->emitULEB128Bytes(Reg);
136 JCE->emitULEB128Bytes(Offset);
142 /// SharedTypeIds - How many leading type ids two landing pads have in common.
143 static unsigned SharedTypeIds(const LandingPadInfo *L,
144 const LandingPadInfo *R) {
145 const std::vector<int> &LIds = L->TypeIds, &RIds = R->TypeIds;
146 unsigned LSize = LIds.size(), RSize = RIds.size();
147 unsigned MinSize = LSize < RSize ? LSize : RSize;
150 for (; Count != MinSize; ++Count)
151 if (LIds[Count] != RIds[Count])
158 /// PadLT - Order landing pads lexicographically by type id.
159 static bool PadLT(const LandingPadInfo *L, const LandingPadInfo *R) {
160 const std::vector<int> &LIds = L->TypeIds, &RIds = R->TypeIds;
161 unsigned LSize = LIds.size(), RSize = RIds.size();
162 unsigned MinSize = LSize < RSize ? LSize : RSize;
164 for (unsigned i = 0; i != MinSize; ++i)
165 if (LIds[i] != RIds[i])
166 return LIds[i] < RIds[i];
168 return LSize < RSize;
174 static inline unsigned getEmptyKey() { return -1U; }
175 static inline unsigned getTombstoneKey() { return -2U; }
176 static unsigned getHashValue(const unsigned &Key) { return Key; }
177 static bool isEqual(unsigned LHS, unsigned RHS) { return LHS == RHS; }
178 static bool isPod() { return true; }
181 /// ActionEntry - Structure describing an entry in the actions table.
183 int ValueForTypeID; // The value to write - may not be equal to the type id.
185 struct ActionEntry *Previous;
188 /// PadRange - Structure holding a try-range and the associated landing pad.
190 // The index of the landing pad.
192 // The index of the begin and end labels in the landing pad's label lists.
196 typedef DenseMap<unsigned, PadRange, KeyInfo> RangeMapType;
198 /// CallSiteEntry - Structure describing an entry in the call-site table.
199 struct CallSiteEntry {
200 unsigned BeginLabel; // zero indicates the start of the function.
201 unsigned EndLabel; // zero indicates the end of the function.
202 unsigned PadLabel; // zero indicates that there is no landing pad.
208 unsigned char* JITDwarfEmitter::EmitExceptionTable(MachineFunction* MF,
209 unsigned char* StartFunction,
210 unsigned char* EndFunction) const {
211 assert(MMI && "MachineModuleInfo not registered!");
213 // Map all labels and get rid of any dead landing pads.
214 MMI->TidyLandingPads();
216 const std::vector<GlobalVariable *> &TypeInfos = MMI->getTypeInfos();
217 const std::vector<unsigned> &FilterIds = MMI->getFilterIds();
218 const std::vector<LandingPadInfo> &PadInfos = MMI->getLandingPads();
219 if (PadInfos.empty()) return 0;
221 // Sort the landing pads in order of their type ids. This is used to fold
222 // duplicate actions.
223 SmallVector<const LandingPadInfo *, 64> LandingPads;
224 LandingPads.reserve(PadInfos.size());
225 for (unsigned i = 0, N = PadInfos.size(); i != N; ++i)
226 LandingPads.push_back(&PadInfos[i]);
227 std::sort(LandingPads.begin(), LandingPads.end(), PadLT);
229 // Negative type ids index into FilterIds, positive type ids index into
230 // TypeInfos. The value written for a positive type id is just the type
231 // id itself. For a negative type id, however, the value written is the
232 // (negative) byte offset of the corresponding FilterIds entry. The byte
233 // offset is usually equal to the type id, because the FilterIds entries
234 // are written using a variable width encoding which outputs one byte per
235 // entry as long as the value written is not too large, but can differ.
236 // This kind of complication does not occur for positive type ids because
237 // type infos are output using a fixed width encoding.
238 // FilterOffsets[i] holds the byte offset corresponding to FilterIds[i].
239 SmallVector<int, 16> FilterOffsets;
240 FilterOffsets.reserve(FilterIds.size());
242 for(std::vector<unsigned>::const_iterator I = FilterIds.begin(),
243 E = FilterIds.end(); I != E; ++I) {
244 FilterOffsets.push_back(Offset);
245 Offset -= MCAsmInfo::getULEB128Size(*I);
248 // Compute the actions table and gather the first action index for each
250 SmallVector<ActionEntry, 32> Actions;
251 SmallVector<unsigned, 64> FirstActions;
252 FirstActions.reserve(LandingPads.size());
255 unsigned SizeActions = 0;
256 for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) {
257 const LandingPadInfo *LP = LandingPads[i];
258 const std::vector<int> &TypeIds = LP->TypeIds;
259 const unsigned NumShared = i ? SharedTypeIds(LP, LandingPads[i-1]) : 0;
260 unsigned SizeSiteActions = 0;
262 if (NumShared < TypeIds.size()) {
263 unsigned SizeAction = 0;
264 ActionEntry *PrevAction = 0;
267 const unsigned SizePrevIds = LandingPads[i-1]->TypeIds.size();
268 assert(Actions.size());
269 PrevAction = &Actions.back();
270 SizeAction = MCAsmInfo::getSLEB128Size(PrevAction->NextAction) +
271 MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
272 for (unsigned j = NumShared; j != SizePrevIds; ++j) {
273 SizeAction -= MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
274 SizeAction += -PrevAction->NextAction;
275 PrevAction = PrevAction->Previous;
279 // Compute the actions.
280 for (unsigned I = NumShared, M = TypeIds.size(); I != M; ++I) {
281 int TypeID = TypeIds[I];
282 assert(-1-TypeID < (int)FilterOffsets.size() && "Unknown filter id!");
283 int ValueForTypeID = TypeID < 0 ? FilterOffsets[-1 - TypeID] : TypeID;
284 unsigned SizeTypeID = MCAsmInfo::getSLEB128Size(ValueForTypeID);
286 int NextAction = SizeAction ? -(SizeAction + SizeTypeID) : 0;
287 SizeAction = SizeTypeID + MCAsmInfo::getSLEB128Size(NextAction);
288 SizeSiteActions += SizeAction;
290 ActionEntry Action = {ValueForTypeID, NextAction, PrevAction};
291 Actions.push_back(Action);
293 PrevAction = &Actions.back();
296 // Record the first action of the landing pad site.
297 FirstAction = SizeActions + SizeSiteActions - SizeAction + 1;
298 } // else identical - re-use previous FirstAction
300 FirstActions.push_back(FirstAction);
302 // Compute this sites contribution to size.
303 SizeActions += SizeSiteActions;
306 // Compute the call-site table. Entries must be ordered by address.
307 SmallVector<CallSiteEntry, 64> CallSites;
310 for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) {
311 const LandingPadInfo *LandingPad = LandingPads[i];
312 for (unsigned j=0, E = LandingPad->BeginLabels.size(); j != E; ++j) {
313 unsigned BeginLabel = LandingPad->BeginLabels[j];
314 assert(!PadMap.count(BeginLabel) && "Duplicate landing pad labels!");
315 PadRange P = { i, j };
316 PadMap[BeginLabel] = P;
320 bool MayThrow = false;
321 unsigned LastLabel = 0;
322 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
324 for (MachineBasicBlock::const_iterator MI = I->begin(), E = I->end();
326 if (!MI->isLabel()) {
327 MayThrow |= MI->getDesc().isCall();
331 unsigned BeginLabel = MI->getOperand(0).getImm();
332 assert(BeginLabel && "Invalid label!");
334 if (BeginLabel == LastLabel)
337 RangeMapType::iterator L = PadMap.find(BeginLabel);
339 if (L == PadMap.end())
342 PadRange P = L->second;
343 const LandingPadInfo *LandingPad = LandingPads[P.PadIndex];
345 assert(BeginLabel == LandingPad->BeginLabels[P.RangeIndex] &&
346 "Inconsistent landing pad map!");
348 // If some instruction between the previous try-range and this one may
349 // throw, create a call-site entry with no landing pad for the region
350 // between the try-ranges.
352 CallSiteEntry Site = {LastLabel, BeginLabel, 0, 0};
353 CallSites.push_back(Site);
356 LastLabel = LandingPad->EndLabels[P.RangeIndex];
357 CallSiteEntry Site = {BeginLabel, LastLabel,
358 LandingPad->LandingPadLabel, FirstActions[P.PadIndex]};
360 assert(Site.BeginLabel && Site.EndLabel && Site.PadLabel &&
361 "Invalid landing pad!");
363 // Try to merge with the previous call-site.
364 if (CallSites.size()) {
365 CallSiteEntry &Prev = CallSites.back();
366 if (Site.PadLabel == Prev.PadLabel && Site.Action == Prev.Action) {
367 // Extend the range of the previous entry.
368 Prev.EndLabel = Site.EndLabel;
373 // Otherwise, create a new call-site.
374 CallSites.push_back(Site);
377 // If some instruction between the previous try-range and the end of the
378 // function may throw, create a call-site entry with no landing pad for the
379 // region following the try-range.
381 CallSiteEntry Site = {LastLabel, 0, 0, 0};
382 CallSites.push_back(Site);
386 unsigned SizeSites = CallSites.size() * (sizeof(int32_t) + // Site start.
387 sizeof(int32_t) + // Site length.
388 sizeof(int32_t)); // Landing pad.
389 for (unsigned i = 0, e = CallSites.size(); i < e; ++i)
390 SizeSites += MCAsmInfo::getULEB128Size(CallSites[i].Action);
392 unsigned SizeTypes = TypeInfos.size() * TD->getPointerSize();
394 unsigned TypeOffset = sizeof(int8_t) + // Call site format
395 // Call-site table length
396 MCAsmInfo::getULEB128Size(SizeSites) +
397 SizeSites + SizeActions + SizeTypes;
399 // Begin the exception table.
400 JCE->emitAlignmentWithFill(4, 0);
401 // Asm->EOL("Padding");
403 unsigned char* DwarfExceptionTable = (unsigned char*)JCE->getCurrentPCValue();
406 JCE->emitByte(dwarf::DW_EH_PE_omit);
407 // Asm->EOL("LPStart format (DW_EH_PE_omit)");
408 JCE->emitByte(dwarf::DW_EH_PE_absptr);
409 // Asm->EOL("TType format (DW_EH_PE_absptr)");
410 JCE->emitULEB128Bytes(TypeOffset);
411 // Asm->EOL("TType base offset");
412 JCE->emitByte(dwarf::DW_EH_PE_udata4);
413 // Asm->EOL("Call site format (DW_EH_PE_udata4)");
414 JCE->emitULEB128Bytes(SizeSites);
415 // Asm->EOL("Call-site table length");
417 // Emit the landing pad site information.
418 for (unsigned i = 0; i < CallSites.size(); ++i) {
419 CallSiteEntry &S = CallSites[i];
420 intptr_t BeginLabelPtr = 0;
421 intptr_t EndLabelPtr = 0;
424 BeginLabelPtr = (intptr_t)StartFunction;
427 BeginLabelPtr = JCE->getLabelAddress(S.BeginLabel);
428 JCE->emitInt32(BeginLabelPtr - (intptr_t)StartFunction);
431 // Asm->EOL("Region start");
434 EndLabelPtr = (intptr_t)EndFunction;
435 JCE->emitInt32((intptr_t)EndFunction - BeginLabelPtr);
437 EndLabelPtr = JCE->getLabelAddress(S.EndLabel);
438 JCE->emitInt32(EndLabelPtr - BeginLabelPtr);
440 //Asm->EOL("Region length");
445 unsigned PadLabelPtr = JCE->getLabelAddress(S.PadLabel);
446 JCE->emitInt32(PadLabelPtr - (intptr_t)StartFunction);
448 // Asm->EOL("Landing pad");
450 JCE->emitULEB128Bytes(S.Action);
451 // Asm->EOL("Action");
455 for (unsigned I = 0, N = Actions.size(); I != N; ++I) {
456 ActionEntry &Action = Actions[I];
458 JCE->emitSLEB128Bytes(Action.ValueForTypeID);
459 //Asm->EOL("TypeInfo index");
460 JCE->emitSLEB128Bytes(Action.NextAction);
461 //Asm->EOL("Next action");
464 // Emit the type ids.
465 for (unsigned M = TypeInfos.size(); M; --M) {
466 GlobalVariable *GV = TypeInfos[M - 1];
469 if (TD->getPointerSize() == sizeof(int32_t))
470 JCE->emitInt32((intptr_t)Jit.getOrEmitGlobalVariable(GV));
472 JCE->emitInt64((intptr_t)Jit.getOrEmitGlobalVariable(GV));
474 if (TD->getPointerSize() == sizeof(int32_t))
479 // Asm->EOL("TypeInfo");
482 // Emit the filter typeids.
483 for (unsigned j = 0, M = FilterIds.size(); j < M; ++j) {
484 unsigned TypeID = FilterIds[j];
485 JCE->emitULEB128Bytes(TypeID);
486 //Asm->EOL("Filter TypeInfo index");
489 JCE->emitAlignmentWithFill(4, 0);
491 return DwarfExceptionTable;
495 JITDwarfEmitter::EmitCommonEHFrame(const Function* Personality) const {
496 unsigned PointerSize = TD->getPointerSize();
497 int stackGrowth = stackGrowthDirection == TargetFrameInfo::StackGrowsUp ?
498 PointerSize : -PointerSize;
500 unsigned char* StartCommonPtr = (unsigned char*)JCE->getCurrentPCValue();
501 // EH Common Frame header
502 JCE->allocateSpace(4, 0);
503 unsigned char* FrameCommonBeginPtr = (unsigned char*)JCE->getCurrentPCValue();
504 JCE->emitInt32((int)0);
505 JCE->emitByte(dwarf::DW_CIE_VERSION);
506 JCE->emitString(Personality ? "zPLR" : "zR");
507 JCE->emitULEB128Bytes(1);
508 JCE->emitSLEB128Bytes(stackGrowth);
509 JCE->emitByte(RI->getDwarfRegNum(RI->getRARegister(), true));
512 // Augmentation Size: 3 small ULEBs of one byte each, and the personality
513 // function which size is PointerSize.
514 JCE->emitULEB128Bytes(3 + PointerSize);
516 // We set the encoding of the personality as direct encoding because we use
517 // the function pointer. The encoding is not relative because the current
518 // PC value may be bigger than the personality function pointer.
519 if (PointerSize == 4) {
520 JCE->emitByte(dwarf::DW_EH_PE_sdata4);
521 JCE->emitInt32(((intptr_t)Jit.getPointerToGlobal(Personality)));
523 JCE->emitByte(dwarf::DW_EH_PE_sdata8);
524 JCE->emitInt64(((intptr_t)Jit.getPointerToGlobal(Personality)));
527 JCE->emitULEB128Bytes(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4);
528 JCE->emitULEB128Bytes(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4);
530 JCE->emitULEB128Bytes(1);
531 JCE->emitULEB128Bytes(dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4);
534 std::vector<MachineMove> Moves;
535 RI->getInitialFrameState(Moves);
536 EmitFrameMoves(0, Moves);
538 JCE->emitAlignmentWithFill(PointerSize, dwarf::DW_CFA_nop);
540 JCE->emitInt32At((uintptr_t*)StartCommonPtr,
541 (uintptr_t)((unsigned char*)JCE->getCurrentPCValue() -
542 FrameCommonBeginPtr));
544 return StartCommonPtr;
549 JITDwarfEmitter::EmitEHFrame(const Function* Personality,
550 unsigned char* StartCommonPtr,
551 unsigned char* StartFunction,
552 unsigned char* EndFunction,
553 unsigned char* ExceptionTable) const {
554 unsigned PointerSize = TD->getPointerSize();
557 unsigned char* StartEHPtr = (unsigned char*)JCE->getCurrentPCValue();
558 JCE->allocateSpace(4, 0);
559 unsigned char* FrameBeginPtr = (unsigned char*)JCE->getCurrentPCValue();
561 JCE->emitInt32(FrameBeginPtr - StartCommonPtr);
562 JCE->emitInt32(StartFunction - (unsigned char*)JCE->getCurrentPCValue());
563 JCE->emitInt32(EndFunction - StartFunction);
565 // If there is a personality and landing pads then point to the language
566 // specific data area in the exception table.
568 JCE->emitULEB128Bytes(PointerSize == 4 ? 4 : 8);
570 if (PointerSize == 4) {
571 if (!MMI->getLandingPads().empty())
572 JCE->emitInt32(ExceptionTable-(unsigned char*)JCE->getCurrentPCValue());
574 JCE->emitInt32((int)0);
576 if (!MMI->getLandingPads().empty())
577 JCE->emitInt64(ExceptionTable-(unsigned char*)JCE->getCurrentPCValue());
579 JCE->emitInt64((int)0);
582 JCE->emitULEB128Bytes(0);
585 // Indicate locations of function specific callee saved registers in
587 EmitFrameMoves((intptr_t)StartFunction, MMI->getFrameMoves());
589 JCE->emitAlignmentWithFill(PointerSize, dwarf::DW_CFA_nop);
591 // Indicate the size of the table
592 JCE->emitInt32At((uintptr_t*)StartEHPtr,
593 (uintptr_t)((unsigned char*)JCE->getCurrentPCValue() -
596 // Double zeroes for the unwind runtime
597 if (PointerSize == 8) {
608 unsigned JITDwarfEmitter::GetDwarfTableSizeInBytes(MachineFunction& F,
610 unsigned char* StartFunction,
611 unsigned char* EndFunction) {
612 const TargetMachine& TM = F.getTarget();
613 TD = TM.getTargetData();
614 stackGrowthDirection = TM.getFrameInfo()->getStackGrowthDirection();
615 RI = TM.getRegisterInfo();
617 unsigned FinalSize = 0;
619 FinalSize += GetExceptionTableSizeInBytes(&F);
621 const std::vector<Function *> Personalities = MMI->getPersonalities();
623 GetCommonEHFrameSizeInBytes(Personalities[MMI->getPersonalityIndex()]);
625 FinalSize += GetEHFrameSizeInBytes(Personalities[MMI->getPersonalityIndex()],
631 /// RoundUpToAlign - Add the specified alignment to FinalSize and returns
633 static unsigned RoundUpToAlign(unsigned FinalSize, unsigned Alignment) {
634 if (Alignment == 0) Alignment = 1;
635 // Since we do not know where the buffer will be allocated, be pessimistic.
636 return FinalSize + Alignment;
640 JITDwarfEmitter::GetEHFrameSizeInBytes(const Function* Personality,
641 unsigned char* StartFunction) const {
642 unsigned PointerSize = TD->getPointerSize();
643 unsigned FinalSize = 0;
645 FinalSize += PointerSize;
647 FinalSize += 3 * PointerSize;
648 // If there is a personality and landing pads then point to the language
649 // specific data area in the exception table.
651 FinalSize += MCAsmInfo::getULEB128Size(4);
652 FinalSize += PointerSize;
654 FinalSize += MCAsmInfo::getULEB128Size(0);
657 // Indicate locations of function specific callee saved registers in
659 FinalSize += GetFrameMovesSizeInBytes((intptr_t)StartFunction,
660 MMI->getFrameMoves());
662 FinalSize = RoundUpToAlign(FinalSize, 4);
664 // Double zeroes for the unwind runtime
665 FinalSize += 2 * PointerSize;
670 unsigned JITDwarfEmitter::GetCommonEHFrameSizeInBytes(const Function* Personality)
673 unsigned PointerSize = TD->getPointerSize();
674 int stackGrowth = stackGrowthDirection == TargetFrameInfo::StackGrowsUp ?
675 PointerSize : -PointerSize;
676 unsigned FinalSize = 0;
677 // EH Common Frame header
678 FinalSize += PointerSize;
681 FinalSize += Personality ? 5 : 3; // "zPLR" or "zR"
682 FinalSize += MCAsmInfo::getULEB128Size(1);
683 FinalSize += MCAsmInfo::getSLEB128Size(stackGrowth);
687 FinalSize += MCAsmInfo::getULEB128Size(7);
692 FinalSize += PointerSize;
694 FinalSize += MCAsmInfo::getULEB128Size(dwarf::DW_EH_PE_pcrel);
695 FinalSize += MCAsmInfo::getULEB128Size(dwarf::DW_EH_PE_pcrel);
698 FinalSize += MCAsmInfo::getULEB128Size(1);
699 FinalSize += MCAsmInfo::getULEB128Size(dwarf::DW_EH_PE_pcrel);
702 std::vector<MachineMove> Moves;
703 RI->getInitialFrameState(Moves);
704 FinalSize += GetFrameMovesSizeInBytes(0, Moves);
705 FinalSize = RoundUpToAlign(FinalSize, 4);
710 JITDwarfEmitter::GetFrameMovesSizeInBytes(intptr_t BaseLabelPtr,
711 const std::vector<MachineMove> &Moves) const {
712 unsigned PointerSize = TD->getPointerSize();
713 int stackGrowth = stackGrowthDirection == TargetFrameInfo::StackGrowsUp ?
714 PointerSize : -PointerSize;
715 bool IsLocal = BaseLabelPtr;
716 unsigned FinalSize = 0;
718 for (unsigned i = 0, N = Moves.size(); i < N; ++i) {
719 const MachineMove &Move = Moves[i];
720 unsigned LabelID = Move.getLabelID();
723 LabelID = MMI->MappedLabel(LabelID);
725 // Throw out move if the label is invalid.
726 if (!LabelID) continue;
729 intptr_t LabelPtr = 0;
730 if (LabelID) LabelPtr = JCE->getLabelAddress(LabelID);
732 const MachineLocation &Dst = Move.getDestination();
733 const MachineLocation &Src = Move.getSource();
735 // Advance row if new location.
736 if (BaseLabelPtr && LabelID && (BaseLabelPtr != LabelPtr || !IsLocal)) {
738 FinalSize += PointerSize;
739 BaseLabelPtr = LabelPtr;
744 if (Dst.isReg() && Dst.getReg() == MachineLocation::VirtualFP) {
746 if (Src.getReg() == MachineLocation::VirtualFP) {
750 unsigned RegNum = RI->getDwarfRegNum(Src.getReg(), true);
751 FinalSize += MCAsmInfo::getULEB128Size(RegNum);
754 int Offset = -Src.getOffset();
756 FinalSize += MCAsmInfo::getULEB128Size(Offset);
758 llvm_unreachable("Machine move no supported yet.");
760 } else if (Src.isReg() &&
761 Src.getReg() == MachineLocation::VirtualFP) {
764 unsigned RegNum = RI->getDwarfRegNum(Dst.getReg(), true);
765 FinalSize += MCAsmInfo::getULEB128Size(RegNum);
767 llvm_unreachable("Machine move no supported yet.");
770 unsigned Reg = RI->getDwarfRegNum(Src.getReg(), true);
771 int Offset = Dst.getOffset() / stackGrowth;
775 FinalSize += MCAsmInfo::getULEB128Size(Reg);
776 FinalSize += MCAsmInfo::getSLEB128Size(Offset);
777 } else if (Reg < 64) {
779 FinalSize += MCAsmInfo::getULEB128Size(Offset);
782 FinalSize += MCAsmInfo::getULEB128Size(Reg);
783 FinalSize += MCAsmInfo::getULEB128Size(Offset);
791 JITDwarfEmitter::GetExceptionTableSizeInBytes(MachineFunction* MF) const {
792 unsigned FinalSize = 0;
794 // Map all labels and get rid of any dead landing pads.
795 MMI->TidyLandingPads();
797 const std::vector<GlobalVariable *> &TypeInfos = MMI->getTypeInfos();
798 const std::vector<unsigned> &FilterIds = MMI->getFilterIds();
799 const std::vector<LandingPadInfo> &PadInfos = MMI->getLandingPads();
800 if (PadInfos.empty()) return 0;
802 // Sort the landing pads in order of their type ids. This is used to fold
803 // duplicate actions.
804 SmallVector<const LandingPadInfo *, 64> LandingPads;
805 LandingPads.reserve(PadInfos.size());
806 for (unsigned i = 0, N = PadInfos.size(); i != N; ++i)
807 LandingPads.push_back(&PadInfos[i]);
808 std::sort(LandingPads.begin(), LandingPads.end(), PadLT);
810 // Negative type ids index into FilterIds, positive type ids index into
811 // TypeInfos. The value written for a positive type id is just the type
812 // id itself. For a negative type id, however, the value written is the
813 // (negative) byte offset of the corresponding FilterIds entry. The byte
814 // offset is usually equal to the type id, because the FilterIds entries
815 // are written using a variable width encoding which outputs one byte per
816 // entry as long as the value written is not too large, but can differ.
817 // This kind of complication does not occur for positive type ids because
818 // type infos are output using a fixed width encoding.
819 // FilterOffsets[i] holds the byte offset corresponding to FilterIds[i].
820 SmallVector<int, 16> FilterOffsets;
821 FilterOffsets.reserve(FilterIds.size());
823 for(std::vector<unsigned>::const_iterator I = FilterIds.begin(),
824 E = FilterIds.end(); I != E; ++I) {
825 FilterOffsets.push_back(Offset);
826 Offset -= MCAsmInfo::getULEB128Size(*I);
829 // Compute the actions table and gather the first action index for each
831 SmallVector<ActionEntry, 32> Actions;
832 SmallVector<unsigned, 64> FirstActions;
833 FirstActions.reserve(LandingPads.size());
836 unsigned SizeActions = 0;
837 for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) {
838 const LandingPadInfo *LP = LandingPads[i];
839 const std::vector<int> &TypeIds = LP->TypeIds;
840 const unsigned NumShared = i ? SharedTypeIds(LP, LandingPads[i-1]) : 0;
841 unsigned SizeSiteActions = 0;
843 if (NumShared < TypeIds.size()) {
844 unsigned SizeAction = 0;
845 ActionEntry *PrevAction = 0;
848 const unsigned SizePrevIds = LandingPads[i-1]->TypeIds.size();
849 assert(Actions.size());
850 PrevAction = &Actions.back();
851 SizeAction = MCAsmInfo::getSLEB128Size(PrevAction->NextAction) +
852 MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
853 for (unsigned j = NumShared; j != SizePrevIds; ++j) {
854 SizeAction -= MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
855 SizeAction += -PrevAction->NextAction;
856 PrevAction = PrevAction->Previous;
860 // Compute the actions.
861 for (unsigned I = NumShared, M = TypeIds.size(); I != M; ++I) {
862 int TypeID = TypeIds[I];
863 assert(-1-TypeID < (int)FilterOffsets.size() && "Unknown filter id!");
864 int ValueForTypeID = TypeID < 0 ? FilterOffsets[-1 - TypeID] : TypeID;
865 unsigned SizeTypeID = MCAsmInfo::getSLEB128Size(ValueForTypeID);
867 int NextAction = SizeAction ? -(SizeAction + SizeTypeID) : 0;
868 SizeAction = SizeTypeID + MCAsmInfo::getSLEB128Size(NextAction);
869 SizeSiteActions += SizeAction;
871 ActionEntry Action = {ValueForTypeID, NextAction, PrevAction};
872 Actions.push_back(Action);
874 PrevAction = &Actions.back();
877 // Record the first action of the landing pad site.
878 FirstAction = SizeActions + SizeSiteActions - SizeAction + 1;
879 } // else identical - re-use previous FirstAction
881 FirstActions.push_back(FirstAction);
883 // Compute this sites contribution to size.
884 SizeActions += SizeSiteActions;
887 // Compute the call-site table. Entries must be ordered by address.
888 SmallVector<CallSiteEntry, 64> CallSites;
891 for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) {
892 const LandingPadInfo *LandingPad = LandingPads[i];
893 for (unsigned j=0, E = LandingPad->BeginLabels.size(); j != E; ++j) {
894 unsigned BeginLabel = LandingPad->BeginLabels[j];
895 assert(!PadMap.count(BeginLabel) && "Duplicate landing pad labels!");
896 PadRange P = { i, j };
897 PadMap[BeginLabel] = P;
901 bool MayThrow = false;
902 unsigned LastLabel = 0;
903 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
905 for (MachineBasicBlock::const_iterator MI = I->begin(), E = I->end();
907 if (!MI->isLabel()) {
908 MayThrow |= MI->getDesc().isCall();
912 unsigned BeginLabel = MI->getOperand(0).getImm();
913 assert(BeginLabel && "Invalid label!");
915 if (BeginLabel == LastLabel)
918 RangeMapType::iterator L = PadMap.find(BeginLabel);
920 if (L == PadMap.end())
923 PadRange P = L->second;
924 const LandingPadInfo *LandingPad = LandingPads[P.PadIndex];
926 assert(BeginLabel == LandingPad->BeginLabels[P.RangeIndex] &&
927 "Inconsistent landing pad map!");
929 // If some instruction between the previous try-range and this one may
930 // throw, create a call-site entry with no landing pad for the region
931 // between the try-ranges.
933 CallSiteEntry Site = {LastLabel, BeginLabel, 0, 0};
934 CallSites.push_back(Site);
937 LastLabel = LandingPad->EndLabels[P.RangeIndex];
938 CallSiteEntry Site = {BeginLabel, LastLabel,
939 LandingPad->LandingPadLabel, FirstActions[P.PadIndex]};
941 assert(Site.BeginLabel && Site.EndLabel && Site.PadLabel &&
942 "Invalid landing pad!");
944 // Try to merge with the previous call-site.
945 if (CallSites.size()) {
946 CallSiteEntry &Prev = CallSites.back();
947 if (Site.PadLabel == Prev.PadLabel && Site.Action == Prev.Action) {
948 // Extend the range of the previous entry.
949 Prev.EndLabel = Site.EndLabel;
954 // Otherwise, create a new call-site.
955 CallSites.push_back(Site);
958 // If some instruction between the previous try-range and the end of the
959 // function may throw, create a call-site entry with no landing pad for the
960 // region following the try-range.
962 CallSiteEntry Site = {LastLabel, 0, 0, 0};
963 CallSites.push_back(Site);
967 unsigned SizeSites = CallSites.size() * (sizeof(int32_t) + // Site start.
968 sizeof(int32_t) + // Site length.
969 sizeof(int32_t)); // Landing pad.
970 for (unsigned i = 0, e = CallSites.size(); i < e; ++i)
971 SizeSites += MCAsmInfo::getULEB128Size(CallSites[i].Action);
973 unsigned SizeTypes = TypeInfos.size() * TD->getPointerSize();
975 unsigned TypeOffset = sizeof(int8_t) + // Call site format
976 // Call-site table length
977 MCAsmInfo::getULEB128Size(SizeSites) +
978 SizeSites + SizeActions + SizeTypes;
980 unsigned TotalSize = sizeof(int8_t) + // LPStart format
981 sizeof(int8_t) + // TType format
982 MCAsmInfo::getULEB128Size(TypeOffset) + // TType base offset
985 unsigned SizeAlign = (4 - TotalSize) & 3;
987 // Begin the exception table.
988 FinalSize = RoundUpToAlign(FinalSize, 4);
989 for (unsigned i = 0; i != SizeAlign; ++i) {
993 unsigned PointerSize = TD->getPointerSize();
997 // Asm->EOL("LPStart format (DW_EH_PE_omit)");
999 // Asm->EOL("TType format (DW_EH_PE_absptr)");
1001 // Asm->EOL("TType base offset");
1003 // Asm->EOL("Call site format (DW_EH_PE_udata4)");
1005 // Asm->EOL("Call-site table length");
1007 // Emit the landing pad site information.
1008 for (unsigned i = 0; i < CallSites.size(); ++i) {
1009 CallSiteEntry &S = CallSites[i];
1011 // Asm->EOL("Region start");
1012 FinalSize += PointerSize;
1014 //Asm->EOL("Region length");
1015 FinalSize += PointerSize;
1017 // Asm->EOL("Landing pad");
1018 FinalSize += PointerSize;
1020 FinalSize += MCAsmInfo::getULEB128Size(S.Action);
1021 // Asm->EOL("Action");
1024 // Emit the actions.
1025 for (unsigned I = 0, N = Actions.size(); I != N; ++I) {
1026 ActionEntry &Action = Actions[I];
1028 //Asm->EOL("TypeInfo index");
1029 FinalSize += MCAsmInfo::getSLEB128Size(Action.ValueForTypeID);
1030 //Asm->EOL("Next action");
1031 FinalSize += MCAsmInfo::getSLEB128Size(Action.NextAction);
1034 // Emit the type ids.
1035 for (unsigned M = TypeInfos.size(); M; --M) {
1036 // Asm->EOL("TypeInfo");
1037 FinalSize += PointerSize;
1040 // Emit the filter typeids.
1041 for (unsigned j = 0, M = FilterIds.size(); j < M; ++j) {
1042 unsigned TypeID = FilterIds[j];
1043 FinalSize += MCAsmInfo::getULEB128Size(TypeID);
1044 //Asm->EOL("Filter TypeInfo index");
1047 FinalSize = RoundUpToAlign(FinalSize, 4);