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 virtual void emitFnStart();
118 virtual void emitFnEnd();
119 virtual void emitCantUnwind();
120 virtual void emitPersonality(const MCSymbol *Personality);
121 virtual void emitPersonalityIndex(unsigned Index);
122 virtual void emitHandlerData();
123 virtual void emitSetFP(unsigned FpReg, unsigned SpReg, int64_t Offset = 0);
124 virtual void emitMovSP(unsigned Reg, int64_t Offset = 0);
125 virtual void emitPad(int64_t Offset);
126 virtual void emitRegSave(const SmallVectorImpl<unsigned> &RegList,
128 virtual void emitUnwindRaw(int64_t Offset,
129 const SmallVectorImpl<uint8_t> &Opcodes);
131 virtual void switchVendor(StringRef Vendor);
132 virtual void emitAttribute(unsigned Attribute, unsigned Value);
133 virtual void emitTextAttribute(unsigned Attribute, StringRef String);
134 virtual void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
135 StringRef StrinValue);
136 virtual void emitArch(unsigned Arch);
137 virtual void emitObjectArch(unsigned Arch);
138 virtual void emitFPU(unsigned FPU);
139 virtual void emitInst(uint32_t Inst, char Suffix = '\0');
140 virtual void finishAttributeSection();
142 virtual void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE);
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 virtual void emitFnStart();
387 virtual void emitFnEnd();
388 virtual void emitCantUnwind();
389 virtual void emitPersonality(const MCSymbol *Personality);
390 virtual void emitPersonalityIndex(unsigned Index);
391 virtual void emitHandlerData();
392 virtual void emitSetFP(unsigned FpReg, unsigned SpReg, int64_t Offset = 0);
393 virtual void emitMovSP(unsigned Reg, int64_t Offset = 0);
394 virtual void emitPad(int64_t Offset);
395 virtual void emitRegSave(const SmallVectorImpl<unsigned> &RegList,
397 virtual void emitUnwindRaw(int64_t Offset,
398 const SmallVectorImpl<uint8_t> &Opcodes);
400 virtual void switchVendor(StringRef Vendor);
401 virtual void emitAttribute(unsigned Attribute, unsigned Value);
402 virtual void emitTextAttribute(unsigned Attribute, StringRef String);
403 virtual void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
404 StringRef StringValue);
405 virtual void emitArch(unsigned Arch);
406 virtual void emitObjectArch(unsigned Arch);
407 virtual void emitFPU(unsigned FPU);
408 virtual void emitInst(uint32_t Inst, char Suffix = '\0');
409 virtual void finishAttributeSection();
411 virtual void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE);
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 virtual void FinishImpl();
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 virtual void ChangeSection(const MCSection *Section,
463 const MCExpr *Subsection) {
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 virtual void EmitInstruction(const MCInst& Inst, const MCSubtargetInfo &STI) {
478 EmitThumbMappingSymbol();
480 EmitARMMappingSymbol();
482 MCELFStreamer::EmitInstruction(Inst, STI);
485 virtual void emitInst(uint32_t Inst, char Suffix) {
488 const bool LittleEndian = getContext().getAsmInfo()->isLittleEndian();
495 EmitARMMappingSymbol();
496 for (unsigned II = 0, IE = Size; II != IE; II++) {
497 const unsigned I = LittleEndian ? (Size - II - 1) : II;
498 Buffer[Size - II - 1] = uint8_t(Inst >> I * CHAR_BIT);
504 Size = (Suffix == 'n' ? 2 : 4);
507 EmitThumbMappingSymbol();
508 for (unsigned II = 0, IE = Size; II != IE; II = II + 2) {
509 const unsigned I0 = LittleEndian ? II + 0 : (Size - II - 1);
510 const unsigned I1 = LittleEndian ? II + 1 : (Size - II - 2);
511 Buffer[Size - II - 2] = uint8_t(Inst >> I0 * CHAR_BIT);
512 Buffer[Size - II - 1] = uint8_t(Inst >> I1 * CHAR_BIT);
517 llvm_unreachable("Invalid Suffix");
520 MCELFStreamer::EmitBytes(StringRef(Buffer, Size));
523 /// This is one of the functions used to emit data into an ELF section, so the
524 /// ARM streamer overrides it to add the appropriate mapping symbol ($d) if
526 virtual void EmitBytes(StringRef Data) {
527 EmitDataMappingSymbol();
528 MCELFStreamer::EmitBytes(Data);
531 /// This is one of the functions used to emit data into an ELF section, so the
532 /// ARM streamer overrides it to add the appropriate mapping symbol ($d) if
534 virtual void EmitValueImpl(const MCExpr *Value, unsigned Size) {
535 EmitDataMappingSymbol();
536 MCELFStreamer::EmitValueImpl(Value, Size);
539 virtual void EmitAssemblerFlag(MCAssemblerFlag Flag) {
540 MCELFStreamer::EmitAssemblerFlag(Flag);
543 case MCAF_SyntaxUnified:
544 return; // no-op here.
547 return; // Change to Thumb mode
550 return; // Change to ARM mode
553 case MCAF_SubsectionsViaSymbols:
559 enum ElfMappingSymbol {
566 void EmitDataMappingSymbol() {
567 if (LastEMS == EMS_Data) return;
568 EmitMappingSymbol("$d");
572 void EmitThumbMappingSymbol() {
573 if (LastEMS == EMS_Thumb) return;
574 EmitMappingSymbol("$t");
578 void EmitARMMappingSymbol() {
579 if (LastEMS == EMS_ARM) return;
580 EmitMappingSymbol("$a");
584 void EmitMappingSymbol(StringRef Name) {
585 MCSymbol *Start = getContext().CreateTempSymbol();
589 getContext().GetOrCreateSymbol(Name + "." +
590 Twine(MappingSymbolCounter++));
592 MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
593 MCELF::SetType(SD, ELF::STT_NOTYPE);
594 MCELF::SetBinding(SD, ELF::STB_LOCAL);
595 SD.setExternal(false);
596 AssignSection(Symbol, getCurrentSection().first);
598 const MCExpr *Value = MCSymbolRefExpr::Create(Start, getContext());
599 Symbol->setVariableValue(Value);
602 void EmitThumbFunc(MCSymbol *Func) {
603 // FIXME: Anything needed here to flag the function as thumb?
605 getAssembler().setIsThumbFunc(Func);
607 MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Func);
608 SD.setFlags(SD.getFlags() | ELF_Other_ThumbFunc);
611 // Helper functions for ARM exception handling directives
614 void EmitPersonalityFixup(StringRef Name);
615 void FlushPendingOffset();
616 void FlushUnwindOpcodes(bool NoHandlerData);
618 void SwitchToEHSection(const char *Prefix, unsigned Type, unsigned Flags,
619 SectionKind Kind, const MCSymbol &Fn);
620 void SwitchToExTabSection(const MCSymbol &FnStart);
621 void SwitchToExIdxSection(const MCSymbol &FnStart);
623 void EmitFixup(const MCExpr *Expr, MCFixupKind Kind);
626 int64_t MappingSymbolCounter;
628 DenseMap<const MCSection *, ElfMappingSymbol> LastMappingSymbols;
629 ElfMappingSymbol LastEMS;
631 // ARM Exception Handling Frame Information
634 const MCSymbol *Personality;
635 unsigned PersonalityIndex;
636 unsigned FPReg; // Frame pointer register
637 int64_t FPOffset; // Offset: (final frame pointer) - (initial $sp)
638 int64_t SPOffset; // Offset: (final $sp) - (initial $sp)
639 int64_t PendingOffset; // Offset: (final $sp) - (emitted $sp)
642 SmallVector<uint8_t, 64> Opcodes;
643 UnwindOpcodeAssembler UnwindOpAsm;
645 } // end anonymous namespace
647 ARMELFStreamer &ARMTargetELFStreamer::getStreamer() {
648 return static_cast<ARMELFStreamer &>(Streamer);
651 void ARMTargetELFStreamer::emitFnStart() { getStreamer().emitFnStart(); }
652 void ARMTargetELFStreamer::emitFnEnd() { getStreamer().emitFnEnd(); }
653 void ARMTargetELFStreamer::emitCantUnwind() { getStreamer().emitCantUnwind(); }
654 void ARMTargetELFStreamer::emitPersonality(const MCSymbol *Personality) {
655 getStreamer().emitPersonality(Personality);
657 void ARMTargetELFStreamer::emitPersonalityIndex(unsigned Index) {
658 getStreamer().emitPersonalityIndex(Index);
660 void ARMTargetELFStreamer::emitHandlerData() {
661 getStreamer().emitHandlerData();
663 void ARMTargetELFStreamer::emitSetFP(unsigned FpReg, unsigned SpReg,
665 getStreamer().emitSetFP(FpReg, SpReg, Offset);
667 void ARMTargetELFStreamer::emitMovSP(unsigned Reg, int64_t Offset) {
668 getStreamer().emitMovSP(Reg, Offset);
670 void ARMTargetELFStreamer::emitPad(int64_t Offset) {
671 getStreamer().emitPad(Offset);
673 void ARMTargetELFStreamer::emitRegSave(const SmallVectorImpl<unsigned> &RegList,
675 getStreamer().emitRegSave(RegList, isVector);
677 void ARMTargetELFStreamer::emitUnwindRaw(int64_t Offset,
678 const SmallVectorImpl<uint8_t> &Opcodes) {
679 getStreamer().emitUnwindRaw(Offset, Opcodes);
681 void ARMTargetELFStreamer::switchVendor(StringRef Vendor) {
682 assert(!Vendor.empty() && "Vendor cannot be empty.");
684 if (CurrentVendor == Vendor)
687 if (!CurrentVendor.empty())
688 finishAttributeSection();
690 assert(Contents.empty() &&
691 ".ARM.attributes should be flushed before changing vendor");
692 CurrentVendor = Vendor;
695 void ARMTargetELFStreamer::emitAttribute(unsigned Attribute, unsigned Value) {
696 setAttributeItem(Attribute, Value, /* OverwriteExisting= */ true);
698 void ARMTargetELFStreamer::emitTextAttribute(unsigned Attribute,
700 setAttributeItem(Attribute, Value, /* OverwriteExisting= */ true);
702 void ARMTargetELFStreamer::emitIntTextAttribute(unsigned Attribute,
704 StringRef StringValue) {
705 setAttributeItems(Attribute, IntValue, StringValue,
706 /* OverwriteExisting= */ true);
708 void ARMTargetELFStreamer::emitArch(unsigned Value) {
711 void ARMTargetELFStreamer::emitObjectArch(unsigned Value) {
714 void ARMTargetELFStreamer::emitArchDefaultAttributes() {
715 using namespace ARMBuildAttrs;
717 setAttributeItem(CPU_name, GetArchDefaultCPUName(Arch), false);
718 if (EmittedArch == ARM::INVALID_ARCH)
719 setAttributeItem(CPU_arch, GetArchDefaultCPUArch(Arch), false);
721 setAttributeItem(CPU_arch, GetArchDefaultCPUArch(EmittedArch), false);
730 setAttributeItem(ARM_ISA_use, Allowed, false);
738 setAttributeItem(ARM_ISA_use, Allowed, false);
739 setAttributeItem(THUMB_ISA_use, Allowed, false);
743 setAttributeItem(ARM_ISA_use, Allowed, false);
744 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
749 setAttributeItem(ARM_ISA_use, Allowed, false);
750 setAttributeItem(THUMB_ISA_use, Allowed, false);
751 setAttributeItem(Virtualization_use, AllowTZ, false);
755 setAttributeItem(THUMB_ISA_use, Allowed, false);
759 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
763 setAttributeItem(CPU_arch_profile, ApplicationProfile, false);
764 setAttributeItem(ARM_ISA_use, Allowed, false);
765 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
769 setAttributeItem(CPU_arch_profile, RealTimeProfile, false);
770 setAttributeItem(ARM_ISA_use, Allowed, false);
771 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
775 setAttributeItem(CPU_arch_profile, MicroControllerProfile, false);
776 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
780 setAttributeItem(CPU_arch_profile, ApplicationProfile, false);
781 setAttributeItem(ARM_ISA_use, Allowed, false);
782 setAttributeItem(THUMB_ISA_use, AllowThumb32, false);
783 setAttributeItem(MPextension_use, Allowed, false);
784 setAttributeItem(Virtualization_use, AllowTZVirtualization, false);
788 setAttributeItem(ARM_ISA_use, Allowed, false);
789 setAttributeItem(THUMB_ISA_use, Allowed, false);
790 setAttributeItem(WMMX_arch, AllowWMMXv1, false);
794 setAttributeItem(ARM_ISA_use, Allowed, false);
795 setAttributeItem(THUMB_ISA_use, Allowed, false);
796 setAttributeItem(WMMX_arch, AllowWMMXv2, false);
800 report_fatal_error("Unknown Arch: " + Twine(Arch));
804 void ARMTargetELFStreamer::emitFPU(unsigned Value) {
807 void ARMTargetELFStreamer::emitFPUDefaultAttributes() {
811 setAttributeItem(ARMBuildAttrs::FP_arch,
812 ARMBuildAttrs::AllowFPv2,
813 /* OverwriteExisting= */ false);
817 setAttributeItem(ARMBuildAttrs::FP_arch,
818 ARMBuildAttrs::AllowFPv3A,
819 /* OverwriteExisting= */ false);
823 setAttributeItem(ARMBuildAttrs::FP_arch,
824 ARMBuildAttrs::AllowFPv3B,
825 /* OverwriteExisting= */ false);
829 setAttributeItem(ARMBuildAttrs::FP_arch,
830 ARMBuildAttrs::AllowFPv4A,
831 /* OverwriteExisting= */ false);
835 setAttributeItem(ARMBuildAttrs::FP_arch,
836 ARMBuildAttrs::AllowFPv4B,
837 /* OverwriteExisting= */ false);
841 setAttributeItem(ARMBuildAttrs::FP_arch,
842 ARMBuildAttrs::AllowFPARMv8A,
843 /* OverwriteExisting= */ false);
847 setAttributeItem(ARMBuildAttrs::FP_arch,
848 ARMBuildAttrs::AllowFPv3A,
849 /* OverwriteExisting= */ false);
850 setAttributeItem(ARMBuildAttrs::Advanced_SIMD_arch,
851 ARMBuildAttrs::AllowNeon,
852 /* OverwriteExisting= */ false);
855 case ARM::NEON_VFPV4:
856 setAttributeItem(ARMBuildAttrs::FP_arch,
857 ARMBuildAttrs::AllowFPv4A,
858 /* OverwriteExisting= */ false);
859 setAttributeItem(ARMBuildAttrs::Advanced_SIMD_arch,
860 ARMBuildAttrs::AllowNeon2,
861 /* OverwriteExisting= */ false);
864 case ARM::NEON_FP_ARMV8:
865 case ARM::CRYPTO_NEON_FP_ARMV8:
866 setAttributeItem(ARMBuildAttrs::FP_arch,
867 ARMBuildAttrs::AllowFPARMv8A,
868 /* OverwriteExisting= */ false);
869 setAttributeItem(ARMBuildAttrs::Advanced_SIMD_arch,
870 ARMBuildAttrs::AllowNeonARMv8,
871 /* OverwriteExisting= */ false);
878 report_fatal_error("Unknown FPU: " + Twine(FPU));
882 size_t ARMTargetELFStreamer::calculateContentSize() const {
884 for (size_t i = 0; i < Contents.size(); ++i) {
885 AttributeItem item = Contents[i];
887 case AttributeItem::HiddenAttribute:
889 case AttributeItem::NumericAttribute:
890 Result += getULEB128Size(item.Tag);
891 Result += getULEB128Size(item.IntValue);
893 case AttributeItem::TextAttribute:
894 Result += getULEB128Size(item.Tag);
895 Result += item.StringValue.size() + 1; // string + '\0'
897 case AttributeItem::NumericAndTextAttributes:
898 Result += getULEB128Size(item.Tag);
899 Result += getULEB128Size(item.IntValue);
900 Result += item.StringValue.size() + 1; // string + '\0';
906 void ARMTargetELFStreamer::finishAttributeSection() {
908 // [ <section-length> "vendor-name"
909 // [ <file-tag> <size> <attribute>*
910 // | <section-tag> <size> <section-number>* 0 <attribute>*
911 // | <symbol-tag> <size> <symbol-number>* 0 <attribute>*
915 if (FPU != ARM::INVALID_FPU)
916 emitFPUDefaultAttributes();
918 if (Arch != ARM::INVALID_ARCH)
919 emitArchDefaultAttributes();
921 if (Contents.empty())
924 std::sort(Contents.begin(), Contents.end(), AttributeItem::LessTag);
926 ARMELFStreamer &Streamer = getStreamer();
928 // Switch to .ARM.attributes section
929 if (AttributeSection) {
930 Streamer.SwitchSection(AttributeSection);
933 Streamer.getContext().getELFSection(".ARM.attributes",
934 ELF::SHT_ARM_ATTRIBUTES,
936 SectionKind::getMetadata());
937 Streamer.SwitchSection(AttributeSection);
940 Streamer.EmitIntValue(0x41, 1);
943 // Vendor size + Vendor name + '\0'
944 const size_t VendorHeaderSize = 4 + CurrentVendor.size() + 1;
947 const size_t TagHeaderSize = 1 + 4;
949 const size_t ContentsSize = calculateContentSize();
951 Streamer.EmitIntValue(VendorHeaderSize + TagHeaderSize + ContentsSize, 4);
952 Streamer.EmitBytes(CurrentVendor);
953 Streamer.EmitIntValue(0, 1); // '\0'
955 Streamer.EmitIntValue(ARMBuildAttrs::File, 1);
956 Streamer.EmitIntValue(TagHeaderSize + ContentsSize, 4);
958 // Size should have been accounted for already, now
959 // emit each field as its type (ULEB or String)
960 for (size_t i = 0; i < Contents.size(); ++i) {
961 AttributeItem item = Contents[i];
962 Streamer.EmitULEB128IntValue(item.Tag);
964 default: llvm_unreachable("Invalid attribute type");
965 case AttributeItem::NumericAttribute:
966 Streamer.EmitULEB128IntValue(item.IntValue);
968 case AttributeItem::TextAttribute:
969 Streamer.EmitBytes(item.StringValue.upper());
970 Streamer.EmitIntValue(0, 1); // '\0'
972 case AttributeItem::NumericAndTextAttributes:
973 Streamer.EmitULEB128IntValue(item.IntValue);
974 Streamer.EmitBytes(item.StringValue.upper());
975 Streamer.EmitIntValue(0, 1); // '\0'
981 FPU = ARM::INVALID_FPU;
984 ARMTargetELFStreamer::AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *S) {
985 getStreamer().EmitFixup(S, FK_Data_4);
987 void ARMTargetELFStreamer::emitInst(uint32_t Inst, char Suffix) {
988 getStreamer().emitInst(Inst, Suffix);
991 void ARMELFStreamer::FinishImpl() {
992 MCTargetStreamer &TS = *getTargetStreamer();
993 ARMTargetStreamer &ATS = static_cast<ARMTargetStreamer &>(TS);
994 ATS.finishAttributeSection();
996 MCELFStreamer::FinishImpl();
999 inline void ARMELFStreamer::SwitchToEHSection(const char *Prefix,
1003 const MCSymbol &Fn) {
1004 const MCSectionELF &FnSection =
1005 static_cast<const MCSectionELF &>(Fn.getSection());
1007 // Create the name for new section
1008 StringRef FnSecName(FnSection.getSectionName());
1009 SmallString<128> EHSecName(Prefix);
1010 if (FnSecName != ".text") {
1011 EHSecName += FnSecName;
1014 // Get .ARM.extab or .ARM.exidx section
1015 const MCSectionELF *EHSection = NULL;
1016 if (const MCSymbol *Group = FnSection.getGroup()) {
1017 EHSection = getContext().getELFSection(
1018 EHSecName, Type, Flags | ELF::SHF_GROUP, Kind,
1019 FnSection.getEntrySize(), Group->getName());
1021 EHSection = getContext().getELFSection(EHSecName, Type, Flags, Kind);
1023 assert(EHSection && "Failed to get the required EH section");
1025 // Switch to .ARM.extab or .ARM.exidx section
1026 SwitchSection(EHSection);
1027 EmitCodeAlignment(4);
1030 inline void ARMELFStreamer::SwitchToExTabSection(const MCSymbol &FnStart) {
1031 SwitchToEHSection(".ARM.extab",
1034 SectionKind::getDataRel(),
1038 inline void ARMELFStreamer::SwitchToExIdxSection(const MCSymbol &FnStart) {
1039 SwitchToEHSection(".ARM.exidx",
1041 ELF::SHF_ALLOC | ELF::SHF_LINK_ORDER,
1042 SectionKind::getDataRel(),
1045 void ARMELFStreamer::EmitFixup(const MCExpr *Expr, MCFixupKind Kind) {
1046 MCDataFragment *Frag = getOrCreateDataFragment();
1047 Frag->getFixups().push_back(MCFixup::Create(Frag->getContents().size(), Expr,
1051 void ARMELFStreamer::Reset() {
1055 PersonalityIndex = ARM::EHABI::NUM_PERSONALITY_INDEX;
1064 UnwindOpAsm.Reset();
1067 void ARMELFStreamer::emitFnStart() {
1068 assert(FnStart == 0);
1069 FnStart = getContext().CreateTempSymbol();
1073 void ARMELFStreamer::emitFnEnd() {
1074 assert(FnStart && ".fnstart must precedes .fnend");
1076 // Emit unwind opcodes if there is no .handlerdata directive
1077 if (!ExTab && !CantUnwind)
1078 FlushUnwindOpcodes(true);
1080 // Emit the exception index table entry
1081 SwitchToExIdxSection(*FnStart);
1083 if (PersonalityIndex < ARM::EHABI::NUM_PERSONALITY_INDEX)
1084 EmitPersonalityFixup(GetAEABIUnwindPersonalityName(PersonalityIndex));
1086 const MCSymbolRefExpr *FnStartRef =
1087 MCSymbolRefExpr::Create(FnStart,
1088 MCSymbolRefExpr::VK_ARM_PREL31,
1091 EmitValue(FnStartRef, 4);
1094 EmitIntValue(ARM::EHABI::EXIDX_CANTUNWIND, 4);
1096 // Emit a reference to the unwind opcodes in the ".ARM.extab" section.
1097 const MCSymbolRefExpr *ExTabEntryRef =
1098 MCSymbolRefExpr::Create(ExTab,
1099 MCSymbolRefExpr::VK_ARM_PREL31,
1101 EmitValue(ExTabEntryRef, 4);
1103 // For the __aeabi_unwind_cpp_pr0, we have to emit the unwind opcodes in
1104 // the second word of exception index table entry. The size of the unwind
1105 // opcodes should always be 4 bytes.
1106 assert(PersonalityIndex == ARM::EHABI::AEABI_UNWIND_CPP_PR0 &&
1107 "Compact model must use __aeabi_cpp_unwind_pr0 as personality");
1108 assert(Opcodes.size() == 4u &&
1109 "Unwind opcode size for __aeabi_cpp_unwind_pr0 must be equal to 4");
1110 EmitBytes(StringRef(reinterpret_cast<const char*>(Opcodes.data()),
1114 // Switch to the section containing FnStart
1115 SwitchSection(&FnStart->getSection());
1117 // Clean exception handling frame information
1121 void ARMELFStreamer::emitCantUnwind() { CantUnwind = true; }
1123 // Add the R_ARM_NONE fixup at the same position
1124 void ARMELFStreamer::EmitPersonalityFixup(StringRef Name) {
1125 const MCSymbol *PersonalitySym = getContext().GetOrCreateSymbol(Name);
1127 const MCSymbolRefExpr *PersonalityRef = MCSymbolRefExpr::Create(
1128 PersonalitySym, MCSymbolRefExpr::VK_ARM_NONE, getContext());
1130 AddValueSymbols(PersonalityRef);
1131 MCDataFragment *DF = getOrCreateDataFragment();
1132 DF->getFixups().push_back(MCFixup::Create(DF->getContents().size(),
1134 MCFixup::getKindForSize(4, false)));
1137 void ARMELFStreamer::FlushPendingOffset() {
1138 if (PendingOffset != 0) {
1139 UnwindOpAsm.EmitSPOffset(-PendingOffset);
1144 void ARMELFStreamer::FlushUnwindOpcodes(bool NoHandlerData) {
1145 // Emit the unwind opcode to restore $sp.
1147 const MCRegisterInfo *MRI = getContext().getRegisterInfo();
1148 int64_t LastRegSaveSPOffset = SPOffset - PendingOffset;
1149 UnwindOpAsm.EmitSPOffset(LastRegSaveSPOffset - FPOffset);
1150 UnwindOpAsm.EmitSetSP(MRI->getEncodingValue(FPReg));
1152 FlushPendingOffset();
1155 // Finalize the unwind opcode sequence
1156 UnwindOpAsm.Finalize(PersonalityIndex, Opcodes);
1158 // For compact model 0, we have to emit the unwind opcodes in the .ARM.exidx
1159 // section. Thus, we don't have to create an entry in the .ARM.extab
1161 if (NoHandlerData && PersonalityIndex == ARM::EHABI::AEABI_UNWIND_CPP_PR0)
1164 // Switch to .ARM.extab section.
1165 SwitchToExTabSection(*FnStart);
1167 // Create .ARM.extab label for offset in .ARM.exidx
1169 ExTab = getContext().CreateTempSymbol();
1174 const MCSymbolRefExpr *PersonalityRef =
1175 MCSymbolRefExpr::Create(Personality,
1176 MCSymbolRefExpr::VK_ARM_PREL31,
1179 EmitValue(PersonalityRef, 4);
1182 // Emit unwind opcodes
1183 EmitBytes(StringRef(reinterpret_cast<const char *>(Opcodes.data()),
1186 // According to ARM EHABI section 9.2, if the __aeabi_unwind_cpp_pr1() or
1187 // __aeabi_unwind_cpp_pr2() is used, then the handler data must be emitted
1188 // after the unwind opcodes. The handler data consists of several 32-bit
1189 // words, and should be terminated by zero.
1191 // In case that the .handlerdata directive is not specified by the
1192 // programmer, we should emit zero to terminate the handler data.
1193 if (NoHandlerData && !Personality)
1197 void ARMELFStreamer::emitHandlerData() { FlushUnwindOpcodes(false); }
1199 void ARMELFStreamer::emitPersonality(const MCSymbol *Per) {
1201 UnwindOpAsm.setPersonality(Per);
1204 void ARMELFStreamer::emitPersonalityIndex(unsigned Index) {
1205 assert(Index < ARM::EHABI::NUM_PERSONALITY_INDEX && "invalid index");
1206 PersonalityIndex = Index;
1209 void ARMELFStreamer::emitSetFP(unsigned NewFPReg, unsigned NewSPReg,
1211 assert((NewSPReg == ARM::SP || NewSPReg == FPReg) &&
1212 "the operand of .setfp directive should be either $sp or $fp");
1217 if (NewSPReg == ARM::SP)
1218 FPOffset = SPOffset + Offset;
1223 void ARMELFStreamer::emitMovSP(unsigned Reg, int64_t Offset) {
1224 assert((Reg != ARM::SP && Reg != ARM::PC) &&
1225 "the operand of .movsp cannot be either sp or pc");
1226 assert(FPReg == ARM::SP && "current FP must be SP");
1228 FlushPendingOffset();
1231 FPOffset = SPOffset + Offset;
1233 const MCRegisterInfo *MRI = getContext().getRegisterInfo();
1234 UnwindOpAsm.EmitSetSP(MRI->getEncodingValue(FPReg));
1237 void ARMELFStreamer::emitPad(int64_t Offset) {
1238 // Track the change of the $sp offset
1241 // To squash multiple .pad directives, we should delay the unwind opcode
1242 // until the .save, .vsave, .handlerdata, or .fnend directives.
1243 PendingOffset -= Offset;
1246 void ARMELFStreamer::emitRegSave(const SmallVectorImpl<unsigned> &RegList,
1248 // Collect the registers in the register list
1251 const MCRegisterInfo *MRI = getContext().getRegisterInfo();
1252 for (size_t i = 0; i < RegList.size(); ++i) {
1253 unsigned Reg = MRI->getEncodingValue(RegList[i]);
1254 assert(Reg < (IsVector ? 32U : 16U) && "Register out of range");
1255 unsigned Bit = (1u << Reg);
1256 if ((Mask & Bit) == 0) {
1262 // Track the change the $sp offset: For the .save directive, the
1263 // corresponding push instruction will decrease the $sp by (4 * Count).
1264 // For the .vsave directive, the corresponding vpush instruction will
1265 // decrease $sp by (8 * Count).
1266 SPOffset -= Count * (IsVector ? 8 : 4);
1269 FlushPendingOffset();
1271 UnwindOpAsm.EmitVFPRegSave(Mask);
1273 UnwindOpAsm.EmitRegSave(Mask);
1276 void ARMELFStreamer::emitUnwindRaw(int64_t Offset,
1277 const SmallVectorImpl<uint8_t> &Opcodes) {
1278 FlushPendingOffset();
1279 SPOffset = SPOffset - Offset;
1280 UnwindOpAsm.EmitRaw(Opcodes);
1285 MCStreamer *createMCAsmStreamer(MCContext &Ctx, formatted_raw_ostream &OS,
1286 bool isVerboseAsm, bool useCFI,
1287 bool useDwarfDirectory,
1288 MCInstPrinter *InstPrint, MCCodeEmitter *CE,
1289 MCAsmBackend *TAB, bool ShowInst) {
1291 llvm::createAsmStreamer(Ctx, OS, isVerboseAsm, useCFI, useDwarfDirectory,
1292 InstPrint, CE, TAB, ShowInst);
1293 new ARMTargetAsmStreamer(*S, OS, *InstPrint, isVerboseAsm);
1297 MCELFStreamer* createARMELFStreamer(MCContext &Context, MCAsmBackend &TAB,
1298 raw_ostream &OS, MCCodeEmitter *Emitter,
1299 bool RelaxAll, bool NoExecStack,
1301 ARMELFStreamer *S = new ARMELFStreamer(Context, TAB, OS, Emitter, IsThumb);
1302 new ARMTargetELFStreamer(*S);
1303 // FIXME: This should eventually end up somewhere else where more
1304 // intelligent flag decisions can be made. For now we are just maintaining
1305 // the status quo for ARM and setting EF_ARM_EABI_VER5 as the default.
1306 S->getAssembler().setELFHeaderEFlags(ELF::EF_ARM_EABI_VER5);
1309 S->getAssembler().setRelaxAll(true);
1311 S->getAssembler().setNoExecStack(true);