1 //===- lib/MC/ARMELFStreamer.cpp - ELF Object Output for ARM --------------===//
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 assembles .s files and emits ARM ELF .o object files. Different
11 // from generic ELF streamer in emitting mapping symbols ($a, $t and $d) to
12 // delimit regions of data and code.
14 //===----------------------------------------------------------------------===//
16 #include "ARMArchName.h"
17 #include "ARMFPUName.h"
18 #include "ARMRegisterInfo.h"
19 #include "ARMUnwindOpAsm.h"
20 #include "llvm/ADT/SmallPtrSet.h"
21 #include "llvm/ADT/StringExtras.h"
22 #include "llvm/ADT/Twine.h"
23 #include "llvm/MC/MCAsmBackend.h"
24 #include "llvm/MC/MCAsmInfo.h"
25 #include "llvm/MC/MCAssembler.h"
26 #include "llvm/MC/MCCodeEmitter.h"
27 #include "llvm/MC/MCContext.h"
28 #include "llvm/MC/MCELF.h"
29 #include "llvm/MC/MCELFStreamer.h"
30 #include "llvm/MC/MCELFSymbolFlags.h"
31 #include "llvm/MC/MCExpr.h"
32 #include "llvm/MC/MCInst.h"
33 #include "llvm/MC/MCInstPrinter.h"
34 #include "llvm/MC/MCObjectStreamer.h"
35 #include "llvm/MC/MCRegisterInfo.h"
36 #include "llvm/MC/MCSection.h"
37 #include "llvm/MC/MCSectionELF.h"
38 #include "llvm/MC/MCStreamer.h"
39 #include "llvm/MC/MCSymbol.h"
40 #include "llvm/MC/MCValue.h"
41 #include "llvm/Support/ARMBuildAttributes.h"
42 #include "llvm/Support/ARMEHABI.h"
43 #include "llvm/Support/Debug.h"
44 #include "llvm/Support/ELF.h"
45 #include "llvm/Support/FormattedStream.h"
46 #include "llvm/Support/LEB128.h"
47 #include "llvm/Support/raw_ostream.h"
52 static std::string GetAEABIUnwindPersonalityName(unsigned Index) {
53 assert(Index < ARM::EHABI::NUM_PERSONALITY_INDEX &&
54 "Invalid personality index");
55 return (Twine("__aeabi_unwind_cpp_pr") + Twine(Index)).str();
58 static const char *GetFPUName(unsigned ID) {
61 llvm_unreachable("Unknown FPU kind");
63 #define ARM_FPU_NAME(NAME, ID) case ARM::ID: return NAME;
64 #include "ARMFPUName.def"
69 static const char *GetArchName(unsigned ID) {
72 llvm_unreachable("Unknown ARCH kind");
74 #define ARM_ARCH_NAME(NAME, ID, DEFAULT_CPU_NAME, DEFAULT_CPU_ARCH) \
75 case ARM::ID: return NAME;
76 #define ARM_ARCH_ALIAS(NAME, ID) /* empty */
77 #include "ARMArchName.def"
82 static const char *GetArchDefaultCPUName(unsigned ID) {
85 llvm_unreachable("Unknown ARCH kind");
87 #define ARM_ARCH_NAME(NAME, ID, DEFAULT_CPU_NAME, DEFAULT_CPU_ARCH) \
88 case ARM::ID: return DEFAULT_CPU_NAME;
89 #define ARM_ARCH_ALIAS(NAME, ID) /* empty */
90 #include "ARMArchName.def"
95 static unsigned GetArchDefaultCPUArch(unsigned ID) {
98 llvm_unreachable("Unknown ARCH kind");
100 #define ARM_ARCH_NAME(NAME, ID, DEFAULT_CPU_NAME, DEFAULT_CPU_ARCH) \
101 case ARM::ID: return ARMBuildAttrs::DEFAULT_CPU_ARCH;
102 #define ARM_ARCH_ALIAS(NAME, ID) /* empty */
103 #include "ARMArchName.def"
110 class ARMELFStreamer;
112 class ARMTargetAsmStreamer : public ARMTargetStreamer {
113 formatted_raw_ostream &OS;
114 MCInstPrinter &InstPrinter;
117 void emitFnStart() override;
118 void emitFnEnd() override;
119 void emitCantUnwind() override;
120 void emitPersonality(const MCSymbol *Personality) override;
121 void emitPersonalityIndex(unsigned Index) override;
122 void emitHandlerData() override;
123 void emitSetFP(unsigned FpReg, unsigned SpReg, int64_t Offset = 0) override;
124 void emitMovSP(unsigned Reg, int64_t Offset = 0) override;
125 void emitPad(int64_t Offset) override;
126 void emitRegSave(const SmallVectorImpl<unsigned> &RegList,
127 bool isVector) override;
128 void emitUnwindRaw(int64_t Offset,
129 const SmallVectorImpl<uint8_t> &Opcodes) override;
131 void switchVendor(StringRef Vendor) override;
132 void emitAttribute(unsigned Attribute, unsigned Value) override;
133 void emitTextAttribute(unsigned Attribute, StringRef String) override;
134 void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
135 StringRef StrinValue) override;
136 void emitArch(unsigned Arch) override;
137 void emitObjectArch(unsigned Arch) override;
138 void emitFPU(unsigned FPU) override;
139 void emitInst(uint32_t Inst, char Suffix = '\0') override;
140 void finishAttributeSection() override;
142 void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE) override;
145 ARMTargetAsmStreamer(MCStreamer &S, formatted_raw_ostream &OS,
146 MCInstPrinter &InstPrinter, bool VerboseAsm);
149 ARMTargetAsmStreamer::ARMTargetAsmStreamer(MCStreamer &S,
150 formatted_raw_ostream &OS,
151 MCInstPrinter &InstPrinter,
153 : ARMTargetStreamer(S), OS(OS), InstPrinter(InstPrinter),
154 IsVerboseAsm(VerboseAsm) {}
155 void ARMTargetAsmStreamer::emitFnStart() { OS << "\t.fnstart\n"; }
156 void ARMTargetAsmStreamer::emitFnEnd() { OS << "\t.fnend\n"; }
157 void ARMTargetAsmStreamer::emitCantUnwind() { OS << "\t.cantunwind\n"; }
158 void ARMTargetAsmStreamer::emitPersonality(const MCSymbol *Personality) {
159 OS << "\t.personality " << Personality->getName() << '\n';
161 void ARMTargetAsmStreamer::emitPersonalityIndex(unsigned Index) {
162 OS << "\t.personalityindex " << Index << '\n';
164 void ARMTargetAsmStreamer::emitHandlerData() { OS << "\t.handlerdata\n"; }
165 void ARMTargetAsmStreamer::emitSetFP(unsigned FpReg, unsigned SpReg,
168 InstPrinter.printRegName(OS, FpReg);
170 InstPrinter.printRegName(OS, SpReg);
172 OS << ", #" << Offset;
175 void ARMTargetAsmStreamer::emitMovSP(unsigned Reg, int64_t Offset) {
176 assert((Reg != ARM::SP && Reg != ARM::PC) &&
177 "the operand of .movsp cannot be either sp or pc");
180 InstPrinter.printRegName(OS, Reg);
182 OS << ", #" << Offset;
185 void ARMTargetAsmStreamer::emitPad(int64_t Offset) {
186 OS << "\t.pad\t#" << Offset << '\n';
188 void ARMTargetAsmStreamer::emitRegSave(const SmallVectorImpl<unsigned> &RegList,
190 assert(RegList.size() && "RegList should not be empty");
196 InstPrinter.printRegName(OS, RegList[0]);
198 for (unsigned i = 1, e = RegList.size(); i != e; ++i) {
200 InstPrinter.printRegName(OS, RegList[i]);
205 void ARMTargetAsmStreamer::switchVendor(StringRef Vendor) {
207 void ARMTargetAsmStreamer::emitAttribute(unsigned Attribute, unsigned Value) {
208 OS << "\t.eabi_attribute\t" << Attribute << ", " << Twine(Value);
210 StringRef Name = ARMBuildAttrs::AttrTypeAsString(Attribute);
212 OS << "\t@ " << Name;
216 void ARMTargetAsmStreamer::emitTextAttribute(unsigned Attribute,
219 case ARMBuildAttrs::CPU_name:
220 OS << "\t.cpu\t" << String.lower();
223 OS << "\t.eabi_attribute\t" << Attribute << ", \"" << String << "\"";
225 StringRef Name = ARMBuildAttrs::AttrTypeAsString(Attribute);
227 OS << "\t@ " << Name;
233 void ARMTargetAsmStreamer::emitIntTextAttribute(unsigned Attribute,
235 StringRef StringValue) {
237 default: llvm_unreachable("unsupported multi-value attribute in asm mode");
238 case ARMBuildAttrs::compatibility:
239 OS << "\t.eabi_attribute\t" << Attribute << ", " << IntValue;
240 if (!StringValue.empty())
241 OS << ", \"" << StringValue << "\"";
243 OS << "\t@ " << ARMBuildAttrs::AttrTypeAsString(Attribute);
248 void ARMTargetAsmStreamer::emitArch(unsigned Arch) {
249 OS << "\t.arch\t" << GetArchName(Arch) << "\n";
251 void ARMTargetAsmStreamer::emitObjectArch(unsigned Arch) {
252 OS << "\t.object_arch\t" << GetArchName(Arch) << '\n';
254 void ARMTargetAsmStreamer::emitFPU(unsigned FPU) {
255 OS << "\t.fpu\t" << GetFPUName(FPU) << "\n";
257 void ARMTargetAsmStreamer::finishAttributeSection() {
260 ARMTargetAsmStreamer::AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *S) {
261 OS << "\t.tlsdescseq\t" << S->getSymbol().getName();
264 void ARMTargetAsmStreamer::emitInst(uint32_t Inst, char Suffix) {
268 OS << "\t0x" << utohexstr(Inst) << "\n";
271 void ARMTargetAsmStreamer::emitUnwindRaw(int64_t Offset,
272 const SmallVectorImpl<uint8_t> &Opcodes) {
273 OS << "\t.unwind_raw " << Offset;
274 for (SmallVectorImpl<uint8_t>::const_iterator OCI = Opcodes.begin(),
277 OS << ", 0x" << utohexstr(*OCI);
281 class ARMTargetELFStreamer : public ARMTargetStreamer {
283 // This structure holds all attributes, accounting for
284 // their string/numeric value, so we can later emmit them
285 // in declaration order, keeping all in the same vector
286 struct AttributeItem {
291 NumericAndTextAttributes
295 StringRef StringValue;
297 static bool LessTag(const AttributeItem &LHS, const AttributeItem &RHS) {
298 return (LHS.Tag < RHS.Tag);
302 StringRef CurrentVendor;
305 unsigned EmittedArch;
306 SmallVector<AttributeItem, 64> Contents;
308 const MCSection *AttributeSection;
310 AttributeItem *getAttributeItem(unsigned Attribute) {
311 for (size_t i = 0; i < Contents.size(); ++i)
312 if (Contents[i].Tag == Attribute)
317 void setAttributeItem(unsigned Attribute, unsigned Value,
318 bool OverwriteExisting) {
319 // Look for existing attribute item
320 if (AttributeItem *Item = getAttributeItem(Attribute)) {
321 if (!OverwriteExisting)
323 Item->Type = AttributeItem::NumericAttribute;
324 Item->IntValue = Value;
328 // Create new attribute item
329 AttributeItem Item = {
330 AttributeItem::NumericAttribute,
335 Contents.push_back(Item);
338 void setAttributeItem(unsigned Attribute, StringRef Value,
339 bool OverwriteExisting) {
340 // Look for existing attribute item
341 if (AttributeItem *Item = getAttributeItem(Attribute)) {
342 if (!OverwriteExisting)
344 Item->Type = AttributeItem::TextAttribute;
345 Item->StringValue = Value;
349 // Create new attribute item
350 AttributeItem Item = {
351 AttributeItem::TextAttribute,
356 Contents.push_back(Item);
359 void setAttributeItems(unsigned Attribute, unsigned IntValue,
360 StringRef StringValue, bool OverwriteExisting) {
361 // Look for existing attribute item
362 if (AttributeItem *Item = getAttributeItem(Attribute)) {
363 if (!OverwriteExisting)
365 Item->Type = AttributeItem::NumericAndTextAttributes;
366 Item->IntValue = IntValue;
367 Item->StringValue = StringValue;
371 // Create new attribute item
372 AttributeItem Item = {
373 AttributeItem::NumericAndTextAttributes,
378 Contents.push_back(Item);
381 void emitArchDefaultAttributes();
382 void emitFPUDefaultAttributes();
384 ARMELFStreamer &getStreamer();
386 void emitFnStart() override;
387 void emitFnEnd() override;
388 void emitCantUnwind() override;
389 void emitPersonality(const MCSymbol *Personality) override;
390 void emitPersonalityIndex(unsigned Index) override;
391 void emitHandlerData() override;
392 void emitSetFP(unsigned FpReg, unsigned SpReg, int64_t Offset = 0) override;
393 void emitMovSP(unsigned Reg, int64_t Offset = 0) override;
394 void emitPad(int64_t Offset) override;
395 void emitRegSave(const SmallVectorImpl<unsigned> &RegList,
396 bool isVector) override;
397 void emitUnwindRaw(int64_t Offset,
398 const SmallVectorImpl<uint8_t> &Opcodes) override;
400 void switchVendor(StringRef Vendor) override;
401 void emitAttribute(unsigned Attribute, unsigned Value) override;
402 void emitTextAttribute(unsigned Attribute, StringRef String) override;
403 void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
404 StringRef StringValue) override;
405 void emitArch(unsigned Arch) override;
406 void emitObjectArch(unsigned Arch) override;
407 void emitFPU(unsigned FPU) override;
408 void emitInst(uint32_t Inst, char Suffix = '\0') override;
409 void finishAttributeSection() override;
411 void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE) override;
413 size_t calculateContentSize() const;
416 ARMTargetELFStreamer(MCStreamer &S)
417 : ARMTargetStreamer(S), CurrentVendor("aeabi"), FPU(ARM::INVALID_FPU),
418 Arch(ARM::INVALID_ARCH), EmittedArch(ARM::INVALID_ARCH),
419 AttributeSection(0) {}
422 /// Extend the generic ELFStreamer class so that it can emit mapping symbols at
423 /// the appropriate points in the object files. These symbols are defined in the
424 /// ARM ELF ABI: infocenter.arm.com/help/topic/com.arm.../IHI0044D_aaelf.pdf.
426 /// In brief: $a, $t or $d should be emitted at the start of each contiguous
427 /// region of ARM code, Thumb code or data in a section. In practice, this
428 /// emission does not rely on explicit assembler directives but on inherent
429 /// properties of the directives doing the emission (e.g. ".byte" is data, "add
430 /// r0, r0, r0" an instruction).
432 /// As a result this system is orthogonal to the DataRegion infrastructure used
433 /// by MachO. Beware!
434 class ARMELFStreamer : public MCELFStreamer {
436 friend class ARMTargetELFStreamer;
438 ARMELFStreamer(MCContext &Context, MCAsmBackend &TAB, raw_ostream &OS,
439 MCCodeEmitter *Emitter, bool IsThumb)
440 : MCELFStreamer(Context, TAB, OS, Emitter), IsThumb(IsThumb),
441 MappingSymbolCounter(0), LastEMS(EMS_None) {
447 void FinishImpl() override;
449 // ARM exception handling directives
452 void emitCantUnwind();
453 void emitPersonality(const MCSymbol *Per);
454 void emitPersonalityIndex(unsigned index);
455 void emitHandlerData();
456 void emitSetFP(unsigned NewFpReg, unsigned NewSpReg, int64_t Offset = 0);
457 void emitMovSP(unsigned Reg, int64_t Offset = 0);
458 void emitPad(int64_t Offset);
459 void emitRegSave(const SmallVectorImpl<unsigned> &RegList, bool isVector);
460 void emitUnwindRaw(int64_t Offset, const SmallVectorImpl<uint8_t> &Opcodes);
462 void ChangeSection(const MCSection *Section,
463 const MCExpr *Subsection) override {
464 // We have to keep track of the mapping symbol state of any sections we
465 // use. Each one should start off as EMS_None, which is provided as the
466 // default constructor by DenseMap::lookup.
467 LastMappingSymbols[getPreviousSection().first] = LastEMS;
468 LastEMS = LastMappingSymbols.lookup(Section);
470 MCELFStreamer::ChangeSection(Section, Subsection);
473 /// This function is the one used to emit instruction data into the ELF
474 /// streamer. We override it to add the appropriate mapping symbol if
476 void EmitInstruction(const MCInst& Inst,
477 const MCSubtargetInfo &STI) override {
479 EmitThumbMappingSymbol();
481 EmitARMMappingSymbol();
483 MCELFStreamer::EmitInstruction(Inst, STI);
486 void emitInst(uint32_t Inst, char Suffix) {
489 const bool LittleEndian = getContext().getAsmInfo()->isLittleEndian();
496 EmitARMMappingSymbol();
497 for (unsigned II = 0, IE = Size; II != IE; II++) {
498 const unsigned I = LittleEndian ? (Size - II - 1) : II;
499 Buffer[Size - II - 1] = uint8_t(Inst >> I * CHAR_BIT);
505 Size = (Suffix == 'n' ? 2 : 4);
508 EmitThumbMappingSymbol();
509 for (unsigned II = 0, IE = Size; II != IE; II = II + 2) {
510 const unsigned I0 = LittleEndian ? II + 0 : (Size - II - 1);
511 const unsigned I1 = LittleEndian ? II + 1 : (Size - II - 2);
512 Buffer[Size - II - 2] = uint8_t(Inst >> I0 * CHAR_BIT);
513 Buffer[Size - II - 1] = uint8_t(Inst >> I1 * CHAR_BIT);
518 llvm_unreachable("Invalid Suffix");
521 MCELFStreamer::EmitBytes(StringRef(Buffer, Size));
524 /// This is one of the functions used to emit data into an ELF section, so the
525 /// ARM streamer overrides it to add the appropriate mapping symbol ($d) if
527 void EmitBytes(StringRef Data) override {
528 EmitDataMappingSymbol();
529 MCELFStreamer::EmitBytes(Data);
532 /// This is one of the functions used to emit data into an ELF section, so the
533 /// ARM streamer overrides it to add the appropriate mapping symbol ($d) if
535 void EmitValueImpl(const MCExpr *Value, unsigned Size) override {
536 EmitDataMappingSymbol();
537 MCELFStreamer::EmitValueImpl(Value, Size);
540 void EmitAssemblerFlag(MCAssemblerFlag Flag) override {
541 MCELFStreamer::EmitAssemblerFlag(Flag);
544 case MCAF_SyntaxUnified:
545 return; // no-op here.
548 return; // Change to Thumb mode
551 return; // Change to ARM mode
554 case MCAF_SubsectionsViaSymbols:
560 enum ElfMappingSymbol {
567 void EmitDataMappingSymbol() {
568 if (LastEMS == EMS_Data) return;
569 EmitMappingSymbol("$d");
573 void EmitThumbMappingSymbol() {
574 if (LastEMS == EMS_Thumb) return;
575 EmitMappingSymbol("$t");
579 void EmitARMMappingSymbol() {
580 if (LastEMS == EMS_ARM) return;
581 EmitMappingSymbol("$a");
585 void EmitMappingSymbol(StringRef Name) {
586 MCSymbol *Start = getContext().CreateTempSymbol();
590 getContext().GetOrCreateSymbol(Name + "." +
591 Twine(MappingSymbolCounter++));
593 MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
594 MCELF::SetType(SD, ELF::STT_NOTYPE);
595 MCELF::SetBinding(SD, ELF::STB_LOCAL);
596 SD.setExternal(false);
597 AssignSection(Symbol, getCurrentSection().first);
599 const MCExpr *Value = MCSymbolRefExpr::Create(Start, getContext());
600 Symbol->setVariableValue(Value);
603 void EmitThumbFunc(MCSymbol *Func) override {
604 // FIXME: Anything needed here to flag the function as thumb?
606 getAssembler().setIsThumbFunc(Func);
608 MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Func);
609 SD.setFlags(SD.getFlags() | ELF_Other_ThumbFunc);
612 // Helper functions for ARM exception handling directives
615 void EmitPersonalityFixup(StringRef Name);
616 void FlushPendingOffset();
617 void FlushUnwindOpcodes(bool NoHandlerData);
619 void SwitchToEHSection(const char *Prefix, unsigned Type, unsigned Flags,
620 SectionKind Kind, const MCSymbol &Fn);
621 void SwitchToExTabSection(const MCSymbol &FnStart);
622 void SwitchToExIdxSection(const MCSymbol &FnStart);
624 void EmitFixup(const MCExpr *Expr, MCFixupKind Kind);
627 int64_t MappingSymbolCounter;
629 DenseMap<const MCSection *, ElfMappingSymbol> LastMappingSymbols;
630 ElfMappingSymbol LastEMS;
632 // ARM Exception Handling Frame Information
635 const MCSymbol *Personality;
636 unsigned PersonalityIndex;
637 unsigned FPReg; // Frame pointer register
638 int64_t FPOffset; // Offset: (final frame pointer) - (initial $sp)
639 int64_t SPOffset; // Offset: (final $sp) - (initial $sp)
640 int64_t PendingOffset; // Offset: (final $sp) - (emitted $sp)
643 SmallVector<uint8_t, 64> Opcodes;
644 UnwindOpcodeAssembler UnwindOpAsm;
646 } // end anonymous namespace
648 ARMELFStreamer &ARMTargetELFStreamer::getStreamer() {
649 return static_cast<ARMELFStreamer &>(Streamer);
652 void ARMTargetELFStreamer::emitFnStart() { getStreamer().emitFnStart(); }
653 void ARMTargetELFStreamer::emitFnEnd() { getStreamer().emitFnEnd(); }
654 void ARMTargetELFStreamer::emitCantUnwind() { getStreamer().emitCantUnwind(); }
655 void ARMTargetELFStreamer::emitPersonality(const MCSymbol *Personality) {
656 getStreamer().emitPersonality(Personality);
658 void ARMTargetELFStreamer::emitPersonalityIndex(unsigned Index) {
659 getStreamer().emitPersonalityIndex(Index);
661 void ARMTargetELFStreamer::emitHandlerData() {
662 getStreamer().emitHandlerData();
664 void ARMTargetELFStreamer::emitSetFP(unsigned FpReg, unsigned SpReg,
666 getStreamer().emitSetFP(FpReg, SpReg, Offset);
668 void ARMTargetELFStreamer::emitMovSP(unsigned Reg, int64_t Offset) {
669 getStreamer().emitMovSP(Reg, Offset);
671 void ARMTargetELFStreamer::emitPad(int64_t Offset) {
672 getStreamer().emitPad(Offset);
674 void ARMTargetELFStreamer::emitRegSave(const SmallVectorImpl<unsigned> &RegList,
676 getStreamer().emitRegSave(RegList, isVector);
678 void ARMTargetELFStreamer::emitUnwindRaw(int64_t Offset,
679 const SmallVectorImpl<uint8_t> &Opcodes) {
680 getStreamer().emitUnwindRaw(Offset, Opcodes);
682 void ARMTargetELFStreamer::switchVendor(StringRef Vendor) {
683 assert(!Vendor.empty() && "Vendor cannot be empty.");
685 if (CurrentVendor == Vendor)
688 if (!CurrentVendor.empty())
689 finishAttributeSection();
691 assert(Contents.empty() &&
692 ".ARM.attributes should be flushed before changing vendor");
693 CurrentVendor = Vendor;
696 void ARMTargetELFStreamer::emitAttribute(unsigned Attribute, unsigned Value) {
697 setAttributeItem(Attribute, Value, /* OverwriteExisting= */ true);
699 void ARMTargetELFStreamer::emitTextAttribute(unsigned Attribute,
701 setAttributeItem(Attribute, Value, /* OverwriteExisting= */ true);
703 void ARMTargetELFStreamer::emitIntTextAttribute(unsigned Attribute,
705 StringRef StringValue) {
706 setAttributeItems(Attribute, IntValue, StringValue,
707 /* OverwriteExisting= */ true);
709 void ARMTargetELFStreamer::emitArch(unsigned Value) {
712 void ARMTargetELFStreamer::emitObjectArch(unsigned Value) {
715 void ARMTargetELFStreamer::emitArchDefaultAttributes() {
716 using namespace ARMBuildAttrs;
718 setAttributeItem(CPU_name, GetArchDefaultCPUName(Arch), false);
719 if (EmittedArch == ARM::INVALID_ARCH)
720 setAttributeItem(CPU_arch, GetArchDefaultCPUArch(Arch), false);
722 setAttributeItem(CPU_arch, GetArchDefaultCPUArch(EmittedArch), false);
731 setAttributeItem(ARM_ISA_use, Allowed, false);
739 setAttributeItem(ARM_ISA_use, Allowed, false);
740 setAttributeItem(THUMB_ISA_use, Allowed, false);
744 setAttributeItem(ARM_ISA_use, Allowed, false);
745 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
750 setAttributeItem(ARM_ISA_use, Allowed, false);
751 setAttributeItem(THUMB_ISA_use, Allowed, false);
752 setAttributeItem(Virtualization_use, AllowTZ, false);
756 setAttributeItem(THUMB_ISA_use, Allowed, false);
760 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
764 setAttributeItem(CPU_arch_profile, ApplicationProfile, false);
765 setAttributeItem(ARM_ISA_use, Allowed, false);
766 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
770 setAttributeItem(CPU_arch_profile, RealTimeProfile, false);
771 setAttributeItem(ARM_ISA_use, Allowed, false);
772 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
776 setAttributeItem(CPU_arch_profile, MicroControllerProfile, false);
777 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
781 setAttributeItem(CPU_arch_profile, ApplicationProfile, false);
782 setAttributeItem(ARM_ISA_use, Allowed, false);
783 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
784 setAttributeItem(MPextension_use, Allowed, false);
785 setAttributeItem(Virtualization_use, AllowTZVirtualization, false);
789 setAttributeItem(ARM_ISA_use, Allowed, false);
790 setAttributeItem(THUMB_ISA_use, Allowed, false);
791 setAttributeItem(WMMX_arch, AllowWMMXv1, false);
795 setAttributeItem(ARM_ISA_use, Allowed, false);
796 setAttributeItem(THUMB_ISA_use, Allowed, false);
797 setAttributeItem(WMMX_arch, AllowWMMXv2, false);
801 report_fatal_error("Unknown Arch: " + Twine(Arch));
805 void ARMTargetELFStreamer::emitFPU(unsigned Value) {
808 void ARMTargetELFStreamer::emitFPUDefaultAttributes() {
812 setAttributeItem(ARMBuildAttrs::FP_arch,
813 ARMBuildAttrs::AllowFPv2,
814 /* OverwriteExisting= */ false);
818 setAttributeItem(ARMBuildAttrs::FP_arch,
819 ARMBuildAttrs::AllowFPv3A,
820 /* OverwriteExisting= */ false);
824 setAttributeItem(ARMBuildAttrs::FP_arch,
825 ARMBuildAttrs::AllowFPv3B,
826 /* OverwriteExisting= */ false);
830 setAttributeItem(ARMBuildAttrs::FP_arch,
831 ARMBuildAttrs::AllowFPv4A,
832 /* OverwriteExisting= */ false);
836 setAttributeItem(ARMBuildAttrs::FP_arch,
837 ARMBuildAttrs::AllowFPv4B,
838 /* OverwriteExisting= */ false);
842 setAttributeItem(ARMBuildAttrs::FP_arch,
843 ARMBuildAttrs::AllowFPARMv8A,
844 /* OverwriteExisting= */ false);
848 setAttributeItem(ARMBuildAttrs::FP_arch,
849 ARMBuildAttrs::AllowFPv3A,
850 /* OverwriteExisting= */ false);
851 setAttributeItem(ARMBuildAttrs::Advanced_SIMD_arch,
852 ARMBuildAttrs::AllowNeon,
853 /* OverwriteExisting= */ false);
856 case ARM::NEON_VFPV4:
857 setAttributeItem(ARMBuildAttrs::FP_arch,
858 ARMBuildAttrs::AllowFPv4A,
859 /* OverwriteExisting= */ false);
860 setAttributeItem(ARMBuildAttrs::Advanced_SIMD_arch,
861 ARMBuildAttrs::AllowNeon2,
862 /* OverwriteExisting= */ false);
865 case ARM::NEON_FP_ARMV8:
866 case ARM::CRYPTO_NEON_FP_ARMV8:
867 setAttributeItem(ARMBuildAttrs::FP_arch,
868 ARMBuildAttrs::AllowFPARMv8A,
869 /* OverwriteExisting= */ false);
870 setAttributeItem(ARMBuildAttrs::Advanced_SIMD_arch,
871 ARMBuildAttrs::AllowNeonARMv8,
872 /* OverwriteExisting= */ false);
879 report_fatal_error("Unknown FPU: " + Twine(FPU));
883 size_t ARMTargetELFStreamer::calculateContentSize() const {
885 for (size_t i = 0; i < Contents.size(); ++i) {
886 AttributeItem item = Contents[i];
888 case AttributeItem::HiddenAttribute:
890 case AttributeItem::NumericAttribute:
891 Result += getULEB128Size(item.Tag);
892 Result += getULEB128Size(item.IntValue);
894 case AttributeItem::TextAttribute:
895 Result += getULEB128Size(item.Tag);
896 Result += item.StringValue.size() + 1; // string + '\0'
898 case AttributeItem::NumericAndTextAttributes:
899 Result += getULEB128Size(item.Tag);
900 Result += getULEB128Size(item.IntValue);
901 Result += item.StringValue.size() + 1; // string + '\0';
907 void ARMTargetELFStreamer::finishAttributeSection() {
909 // [ <section-length> "vendor-name"
910 // [ <file-tag> <size> <attribute>*
911 // | <section-tag> <size> <section-number>* 0 <attribute>*
912 // | <symbol-tag> <size> <symbol-number>* 0 <attribute>*
916 if (FPU != ARM::INVALID_FPU)
917 emitFPUDefaultAttributes();
919 if (Arch != ARM::INVALID_ARCH)
920 emitArchDefaultAttributes();
922 if (Contents.empty())
925 std::sort(Contents.begin(), Contents.end(), AttributeItem::LessTag);
927 ARMELFStreamer &Streamer = getStreamer();
929 // Switch to .ARM.attributes section
930 if (AttributeSection) {
931 Streamer.SwitchSection(AttributeSection);
934 Streamer.getContext().getELFSection(".ARM.attributes",
935 ELF::SHT_ARM_ATTRIBUTES,
937 SectionKind::getMetadata());
938 Streamer.SwitchSection(AttributeSection);
941 Streamer.EmitIntValue(0x41, 1);
944 // Vendor size + Vendor name + '\0'
945 const size_t VendorHeaderSize = 4 + CurrentVendor.size() + 1;
948 const size_t TagHeaderSize = 1 + 4;
950 const size_t ContentsSize = calculateContentSize();
952 Streamer.EmitIntValue(VendorHeaderSize + TagHeaderSize + ContentsSize, 4);
953 Streamer.EmitBytes(CurrentVendor);
954 Streamer.EmitIntValue(0, 1); // '\0'
956 Streamer.EmitIntValue(ARMBuildAttrs::File, 1);
957 Streamer.EmitIntValue(TagHeaderSize + ContentsSize, 4);
959 // Size should have been accounted for already, now
960 // emit each field as its type (ULEB or String)
961 for (size_t i = 0; i < Contents.size(); ++i) {
962 AttributeItem item = Contents[i];
963 Streamer.EmitULEB128IntValue(item.Tag);
965 default: llvm_unreachable("Invalid attribute type");
966 case AttributeItem::NumericAttribute:
967 Streamer.EmitULEB128IntValue(item.IntValue);
969 case AttributeItem::TextAttribute:
970 Streamer.EmitBytes(item.StringValue.upper());
971 Streamer.EmitIntValue(0, 1); // '\0'
973 case AttributeItem::NumericAndTextAttributes:
974 Streamer.EmitULEB128IntValue(item.IntValue);
975 Streamer.EmitBytes(item.StringValue.upper());
976 Streamer.EmitIntValue(0, 1); // '\0'
982 FPU = ARM::INVALID_FPU;
985 ARMTargetELFStreamer::AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *S) {
986 getStreamer().EmitFixup(S, FK_Data_4);
988 void ARMTargetELFStreamer::emitInst(uint32_t Inst, char Suffix) {
989 getStreamer().emitInst(Inst, Suffix);
992 void ARMELFStreamer::FinishImpl() {
993 MCTargetStreamer &TS = *getTargetStreamer();
994 ARMTargetStreamer &ATS = static_cast<ARMTargetStreamer &>(TS);
995 ATS.finishAttributeSection();
997 MCELFStreamer::FinishImpl();
1000 inline void ARMELFStreamer::SwitchToEHSection(const char *Prefix,
1004 const MCSymbol &Fn) {
1005 const MCSectionELF &FnSection =
1006 static_cast<const MCSectionELF &>(Fn.getSection());
1008 // Create the name for new section
1009 StringRef FnSecName(FnSection.getSectionName());
1010 SmallString<128> EHSecName(Prefix);
1011 if (FnSecName != ".text") {
1012 EHSecName += FnSecName;
1015 // Get .ARM.extab or .ARM.exidx section
1016 const MCSectionELF *EHSection = NULL;
1017 if (const MCSymbol *Group = FnSection.getGroup()) {
1018 EHSection = getContext().getELFSection(
1019 EHSecName, Type, Flags | ELF::SHF_GROUP, Kind,
1020 FnSection.getEntrySize(), Group->getName());
1022 EHSection = getContext().getELFSection(EHSecName, Type, Flags, Kind);
1024 assert(EHSection && "Failed to get the required EH section");
1026 // Switch to .ARM.extab or .ARM.exidx section
1027 SwitchSection(EHSection);
1028 EmitCodeAlignment(4);
1031 inline void ARMELFStreamer::SwitchToExTabSection(const MCSymbol &FnStart) {
1032 SwitchToEHSection(".ARM.extab",
1035 SectionKind::getDataRel(),
1039 inline void ARMELFStreamer::SwitchToExIdxSection(const MCSymbol &FnStart) {
1040 SwitchToEHSection(".ARM.exidx",
1042 ELF::SHF_ALLOC | ELF::SHF_LINK_ORDER,
1043 SectionKind::getDataRel(),
1046 void ARMELFStreamer::EmitFixup(const MCExpr *Expr, MCFixupKind Kind) {
1047 MCDataFragment *Frag = getOrCreateDataFragment();
1048 Frag->getFixups().push_back(MCFixup::Create(Frag->getContents().size(), Expr,
1052 void ARMELFStreamer::Reset() {
1056 PersonalityIndex = ARM::EHABI::NUM_PERSONALITY_INDEX;
1065 UnwindOpAsm.Reset();
1068 void ARMELFStreamer::emitFnStart() {
1069 assert(FnStart == 0);
1070 FnStart = getContext().CreateTempSymbol();
1074 void ARMELFStreamer::emitFnEnd() {
1075 assert(FnStart && ".fnstart must precedes .fnend");
1077 // Emit unwind opcodes if there is no .handlerdata directive
1078 if (!ExTab && !CantUnwind)
1079 FlushUnwindOpcodes(true);
1081 // Emit the exception index table entry
1082 SwitchToExIdxSection(*FnStart);
1084 if (PersonalityIndex < ARM::EHABI::NUM_PERSONALITY_INDEX)
1085 EmitPersonalityFixup(GetAEABIUnwindPersonalityName(PersonalityIndex));
1087 const MCSymbolRefExpr *FnStartRef =
1088 MCSymbolRefExpr::Create(FnStart,
1089 MCSymbolRefExpr::VK_ARM_PREL31,
1092 EmitValue(FnStartRef, 4);
1095 EmitIntValue(ARM::EHABI::EXIDX_CANTUNWIND, 4);
1097 // Emit a reference to the unwind opcodes in the ".ARM.extab" section.
1098 const MCSymbolRefExpr *ExTabEntryRef =
1099 MCSymbolRefExpr::Create(ExTab,
1100 MCSymbolRefExpr::VK_ARM_PREL31,
1102 EmitValue(ExTabEntryRef, 4);
1104 // For the __aeabi_unwind_cpp_pr0, we have to emit the unwind opcodes in
1105 // the second word of exception index table entry. The size of the unwind
1106 // opcodes should always be 4 bytes.
1107 assert(PersonalityIndex == ARM::EHABI::AEABI_UNWIND_CPP_PR0 &&
1108 "Compact model must use __aeabi_cpp_unwind_pr0 as personality");
1109 assert(Opcodes.size() == 4u &&
1110 "Unwind opcode size for __aeabi_cpp_unwind_pr0 must be equal to 4");
1111 EmitBytes(StringRef(reinterpret_cast<const char*>(Opcodes.data()),
1115 // Switch to the section containing FnStart
1116 SwitchSection(&FnStart->getSection());
1118 // Clean exception handling frame information
1122 void ARMELFStreamer::emitCantUnwind() { CantUnwind = true; }
1124 // Add the R_ARM_NONE fixup at the same position
1125 void ARMELFStreamer::EmitPersonalityFixup(StringRef Name) {
1126 const MCSymbol *PersonalitySym = getContext().GetOrCreateSymbol(Name);
1128 const MCSymbolRefExpr *PersonalityRef = MCSymbolRefExpr::Create(
1129 PersonalitySym, MCSymbolRefExpr::VK_ARM_NONE, getContext());
1131 AddValueSymbols(PersonalityRef);
1132 MCDataFragment *DF = getOrCreateDataFragment();
1133 DF->getFixups().push_back(MCFixup::Create(DF->getContents().size(),
1135 MCFixup::getKindForSize(4, false)));
1138 void ARMELFStreamer::FlushPendingOffset() {
1139 if (PendingOffset != 0) {
1140 UnwindOpAsm.EmitSPOffset(-PendingOffset);
1145 void ARMELFStreamer::FlushUnwindOpcodes(bool NoHandlerData) {
1146 // Emit the unwind opcode to restore $sp.
1148 const MCRegisterInfo *MRI = getContext().getRegisterInfo();
1149 int64_t LastRegSaveSPOffset = SPOffset - PendingOffset;
1150 UnwindOpAsm.EmitSPOffset(LastRegSaveSPOffset - FPOffset);
1151 UnwindOpAsm.EmitSetSP(MRI->getEncodingValue(FPReg));
1153 FlushPendingOffset();
1156 // Finalize the unwind opcode sequence
1157 UnwindOpAsm.Finalize(PersonalityIndex, Opcodes);
1159 // For compact model 0, we have to emit the unwind opcodes in the .ARM.exidx
1160 // section. Thus, we don't have to create an entry in the .ARM.extab
1162 if (NoHandlerData && PersonalityIndex == ARM::EHABI::AEABI_UNWIND_CPP_PR0)
1165 // Switch to .ARM.extab section.
1166 SwitchToExTabSection(*FnStart);
1168 // Create .ARM.extab label for offset in .ARM.exidx
1170 ExTab = getContext().CreateTempSymbol();
1175 const MCSymbolRefExpr *PersonalityRef =
1176 MCSymbolRefExpr::Create(Personality,
1177 MCSymbolRefExpr::VK_ARM_PREL31,
1180 EmitValue(PersonalityRef, 4);
1183 // Emit unwind opcodes
1184 EmitBytes(StringRef(reinterpret_cast<const char *>(Opcodes.data()),
1187 // According to ARM EHABI section 9.2, if the __aeabi_unwind_cpp_pr1() or
1188 // __aeabi_unwind_cpp_pr2() is used, then the handler data must be emitted
1189 // after the unwind opcodes. The handler data consists of several 32-bit
1190 // words, and should be terminated by zero.
1192 // In case that the .handlerdata directive is not specified by the
1193 // programmer, we should emit zero to terminate the handler data.
1194 if (NoHandlerData && !Personality)
1198 void ARMELFStreamer::emitHandlerData() { FlushUnwindOpcodes(false); }
1200 void ARMELFStreamer::emitPersonality(const MCSymbol *Per) {
1202 UnwindOpAsm.setPersonality(Per);
1205 void ARMELFStreamer::emitPersonalityIndex(unsigned Index) {
1206 assert(Index < ARM::EHABI::NUM_PERSONALITY_INDEX && "invalid index");
1207 PersonalityIndex = Index;
1210 void ARMELFStreamer::emitSetFP(unsigned NewFPReg, unsigned NewSPReg,
1212 assert((NewSPReg == ARM::SP || NewSPReg == FPReg) &&
1213 "the operand of .setfp directive should be either $sp or $fp");
1218 if (NewSPReg == ARM::SP)
1219 FPOffset = SPOffset + Offset;
1224 void ARMELFStreamer::emitMovSP(unsigned Reg, int64_t Offset) {
1225 assert((Reg != ARM::SP && Reg != ARM::PC) &&
1226 "the operand of .movsp cannot be either sp or pc");
1227 assert(FPReg == ARM::SP && "current FP must be SP");
1229 FlushPendingOffset();
1232 FPOffset = SPOffset + Offset;
1234 const MCRegisterInfo *MRI = getContext().getRegisterInfo();
1235 UnwindOpAsm.EmitSetSP(MRI->getEncodingValue(FPReg));
1238 void ARMELFStreamer::emitPad(int64_t Offset) {
1239 // Track the change of the $sp offset
1242 // To squash multiple .pad directives, we should delay the unwind opcode
1243 // until the .save, .vsave, .handlerdata, or .fnend directives.
1244 PendingOffset -= Offset;
1247 void ARMELFStreamer::emitRegSave(const SmallVectorImpl<unsigned> &RegList,
1249 // Collect the registers in the register list
1252 const MCRegisterInfo *MRI = getContext().getRegisterInfo();
1253 for (size_t i = 0; i < RegList.size(); ++i) {
1254 unsigned Reg = MRI->getEncodingValue(RegList[i]);
1255 assert(Reg < (IsVector ? 32U : 16U) && "Register out of range");
1256 unsigned Bit = (1u << Reg);
1257 if ((Mask & Bit) == 0) {
1263 // Track the change the $sp offset: For the .save directive, the
1264 // corresponding push instruction will decrease the $sp by (4 * Count).
1265 // For the .vsave directive, the corresponding vpush instruction will
1266 // decrease $sp by (8 * Count).
1267 SPOffset -= Count * (IsVector ? 8 : 4);
1270 FlushPendingOffset();
1272 UnwindOpAsm.EmitVFPRegSave(Mask);
1274 UnwindOpAsm.EmitRegSave(Mask);
1277 void ARMELFStreamer::emitUnwindRaw(int64_t Offset,
1278 const SmallVectorImpl<uint8_t> &Opcodes) {
1279 FlushPendingOffset();
1280 SPOffset = SPOffset - Offset;
1281 UnwindOpAsm.EmitRaw(Opcodes);
1286 MCStreamer *createMCAsmStreamer(MCContext &Ctx, formatted_raw_ostream &OS,
1287 bool isVerboseAsm, bool useCFI,
1288 bool useDwarfDirectory,
1289 MCInstPrinter *InstPrint, MCCodeEmitter *CE,
1290 MCAsmBackend *TAB, bool ShowInst) {
1292 llvm::createAsmStreamer(Ctx, OS, isVerboseAsm, useCFI, useDwarfDirectory,
1293 InstPrint, CE, TAB, ShowInst);
1294 new ARMTargetAsmStreamer(*S, OS, *InstPrint, isVerboseAsm);
1298 MCELFStreamer* createARMELFStreamer(MCContext &Context, MCAsmBackend &TAB,
1299 raw_ostream &OS, MCCodeEmitter *Emitter,
1300 bool RelaxAll, bool NoExecStack,
1302 ARMELFStreamer *S = new ARMELFStreamer(Context, TAB, OS, Emitter, IsThumb);
1303 new ARMTargetELFStreamer(*S);
1304 // FIXME: This should eventually end up somewhere else where more
1305 // intelligent flag decisions can be made. For now we are just maintaining
1306 // the status quo for ARM and setting EF_ARM_EABI_VER5 as the default.
1307 S->getAssembler().setELFHeaderEFlags(ELF::EF_ARM_EABI_VER5);
1310 S->getAssembler().setRelaxAll(true);
1312 S->getAssembler().setNoExecStack(true);