1 //===- MCStreamer.h - High-level Streaming Machine Code Output --*- C++ -*-===//
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 declares the MCStreamer class.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_MC_MCSTREAMER_H
15 #define LLVM_MC_MCSTREAMER_H
17 #include "llvm/ADT/ArrayRef.h"
18 #include "llvm/ADT/SmallVector.h"
19 #include "llvm/MC/MCAssembler.h"
20 #include "llvm/MC/MCDirectives.h"
21 #include "llvm/MC/MCDwarf.h"
22 #include "llvm/MC/MCLinkerOptimizationHint.h"
23 #include "llvm/MC/MCWinEH.h"
24 #include "llvm/Support/DataTypes.h"
37 class MCSymbolRefExpr;
38 class MCSubtargetInfo;
42 class formatted_raw_ostream;
43 class AssemblerConstantPools;
45 typedef std::pair<const MCSection *, const MCExpr *> MCSectionSubPair;
47 /// Target specific streamer interface. This is used so that targets can
48 /// implement support for target specific assembly directives.
50 /// If target foo wants to use this, it should implement 3 classes:
51 /// * FooTargetStreamer : public MCTargetStreamer
52 /// * FooTargetAsmStreamer : public FooTargetStreamer
53 /// * FooTargetELFStreamer : public FooTargetStreamer
55 /// FooTargetStreamer should have a pure virtual method for each directive. For
56 /// example, for a ".bar symbol_name" directive, it should have
57 /// virtual emitBar(const MCSymbol &Symbol) = 0;
59 /// The FooTargetAsmStreamer and FooTargetELFStreamer classes implement the
60 /// method. The assembly streamer just prints ".bar symbol_name". The object
61 /// streamer does whatever is needed to implement .bar in the object file.
63 /// In the assembly printer and parser the target streamer can be used by
64 /// calling getTargetStreamer and casting it to FooTargetStreamer:
66 /// MCTargetStreamer &TS = OutStreamer.getTargetStreamer();
67 /// FooTargetStreamer &ATS = static_cast<FooTargetStreamer &>(TS);
69 /// The base classes FooTargetAsmStreamer and FooTargetELFStreamer should
70 /// *never* be treated differently. Callers should always talk to a
71 /// FooTargetStreamer.
72 class MCTargetStreamer {
77 MCTargetStreamer(MCStreamer &S);
78 virtual ~MCTargetStreamer();
80 const MCStreamer &getStreamer() { return Streamer; }
82 // Allow a target to add behavior to the EmitLabel of MCStreamer.
83 virtual void emitLabel(MCSymbol *Symbol);
84 // Allow a target to add behavior to the emitAssignment of MCStreamer.
85 virtual void emitAssignment(MCSymbol *Symbol, const MCExpr *Value);
87 virtual void finish();
90 class AArch64TargetStreamer : public MCTargetStreamer {
92 AArch64TargetStreamer(MCStreamer &S);
93 ~AArch64TargetStreamer();
95 void finish() override;
97 /// Callback used to implement the ldr= pseudo.
98 /// Add a new entry to the constant pool for the current section and return an
99 /// MCExpr that can be used to refer to the constant pool location.
100 const MCExpr *addConstantPoolEntry(const MCExpr *, unsigned Size);
102 /// Callback used to implemnt the .ltorg directive.
103 /// Emit contents of constant pool for the current section.
104 void emitCurrentConstantPool();
106 /// Callback used to implement the .inst directive.
107 virtual void emitInst(uint32_t Inst);
110 std::unique_ptr<AssemblerConstantPools> ConstantPools;
113 // FIXME: declared here because it is used from
114 // lib/CodeGen/AsmPrinter/ARMException.cpp.
115 class ARMTargetStreamer : public MCTargetStreamer {
117 ARMTargetStreamer(MCStreamer &S);
118 ~ARMTargetStreamer();
120 virtual void emitFnStart();
121 virtual void emitFnEnd();
122 virtual void emitCantUnwind();
123 virtual void emitPersonality(const MCSymbol *Personality);
124 virtual void emitPersonalityIndex(unsigned Index);
125 virtual void emitHandlerData();
126 virtual void emitSetFP(unsigned FpReg, unsigned SpReg,
128 virtual void emitMovSP(unsigned Reg, int64_t Offset = 0);
129 virtual void emitPad(int64_t Offset);
130 virtual void emitRegSave(const SmallVectorImpl<unsigned> &RegList,
132 virtual void emitUnwindRaw(int64_t StackOffset,
133 const SmallVectorImpl<uint8_t> &Opcodes);
135 virtual void switchVendor(StringRef Vendor);
136 virtual void emitAttribute(unsigned Attribute, unsigned Value);
137 virtual void emitTextAttribute(unsigned Attribute, StringRef String);
138 virtual void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
139 StringRef StringValue = "");
140 virtual void emitFPU(unsigned FPU);
141 virtual void emitArch(unsigned Arch);
142 virtual void emitObjectArch(unsigned Arch);
143 virtual void finishAttributeSection();
144 virtual void emitInst(uint32_t Inst, char Suffix = '\0');
146 virtual void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE);
148 virtual void emitThumbSet(MCSymbol *Symbol, const MCExpr *Value);
150 void finish() override;
152 /// Callback used to implement the ldr= pseudo.
153 /// Add a new entry to the constant pool for the current section and return an
154 /// MCExpr that can be used to refer to the constant pool location.
155 const MCExpr *addConstantPoolEntry(const MCExpr *);
157 /// Callback used to implemnt the .ltorg directive.
158 /// Emit contents of constant pool for the current section.
159 void emitCurrentConstantPool();
162 std::unique_ptr<AssemblerConstantPools> ConstantPools;
165 /// MCStreamer - Streaming machine code generation interface. This interface
166 /// is intended to provide a programatic interface that is very similar to the
167 /// level that an assembler .s file provides. It has callbacks to emit bytes,
168 /// handle directives, etc. The implementation of this interface retains
169 /// state to know what the current section is etc.
171 /// There are multiple implementations of this interface: one for writing out
172 /// a .s file, and implementations that write out .o files of various formats.
176 std::unique_ptr<MCTargetStreamer> TargetStreamer;
178 MCStreamer(const MCStreamer &) LLVM_DELETED_FUNCTION;
179 MCStreamer &operator=(const MCStreamer &) LLVM_DELETED_FUNCTION;
181 std::vector<MCDwarfFrameInfo> DwarfFrameInfos;
182 MCDwarfFrameInfo *getCurrentDwarfFrameInfo();
183 void EnsureValidDwarfFrame();
185 MCSymbol *EmitCFICommon();
187 std::vector<WinEH::FrameInfo *> WinFrameInfos;
188 WinEH::FrameInfo *CurrentWinFrameInfo;
189 void EnsureValidWinFrameInfo();
191 // SymbolOrdering - Tracks an index to represent the order
192 // a symbol was emitted in. Zero means we did not emit that symbol.
193 DenseMap<const MCSymbol *, unsigned> SymbolOrdering;
195 /// SectionStack - This is stack of current and previous section
196 /// values saved by PushSection.
197 SmallVector<std::pair<MCSectionSubPair, MCSectionSubPair>, 4> SectionStack;
200 MCStreamer(MCContext &Ctx);
202 virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame);
203 virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &CurFrame);
205 WinEH::FrameInfo *getCurrentWinFrameInfo() {
206 return CurrentWinFrameInfo;
209 virtual void EmitWindowsUnwindTables();
211 virtual void EmitRawTextImpl(StringRef String);
214 virtual ~MCStreamer();
216 void visitUsedExpr(const MCExpr &Expr);
217 virtual void visitUsedSymbol(const MCSymbol &Sym);
219 void setTargetStreamer(MCTargetStreamer *TS) {
220 TargetStreamer.reset(TS);
225 virtual void reset();
227 MCContext &getContext() const { return Context; }
229 MCTargetStreamer *getTargetStreamer() {
230 return TargetStreamer.get();
233 unsigned getNumFrameInfos() { return DwarfFrameInfos.size(); }
234 ArrayRef<MCDwarfFrameInfo> getDwarfFrameInfos() const {
235 return DwarfFrameInfos;
238 unsigned getNumWinFrameInfos() { return WinFrameInfos.size(); }
239 ArrayRef<WinEH::FrameInfo *> getWinFrameInfos() const {
240 return WinFrameInfos;
243 void generateCompactUnwindEncodings(MCAsmBackend *MAB);
245 /// @name Assembly File Formatting.
248 /// isVerboseAsm - Return true if this streamer supports verbose assembly
249 /// and if it is enabled.
250 virtual bool isVerboseAsm() const { return false; }
252 /// hasRawTextSupport - Return true if this asm streamer supports emitting
253 /// unformatted text to the .s file with EmitRawText.
254 virtual bool hasRawTextSupport() const { return false; }
256 /// Is the integrated assembler required for this streamer to function
258 virtual bool isIntegratedAssemblerRequired() const { return false; }
260 /// AddComment - Add a comment that can be emitted to the generated .s
261 /// file if applicable as a QoI issue to make the output of the compiler
262 /// more readable. This only affects the MCAsmStreamer, and only when
263 /// verbose assembly output is enabled.
265 /// If the comment includes embedded \n's, they will each get the comment
266 /// prefix as appropriate. The added comment should not end with a \n.
267 virtual void AddComment(const Twine &T) {}
269 /// GetCommentOS - Return a raw_ostream that comments can be written to.
270 /// Unlike AddComment, you are required to terminate comments with \n if you
272 virtual raw_ostream &GetCommentOS();
274 /// Print T and prefix it with the comment string (normally #) and optionally
275 /// a tab. This prints the comment immediately, not at the end of the
276 /// current line. It is basically a safe version of EmitRawText: since it
277 /// only prints comments, the object streamer ignores it instead of asserting.
278 virtual void emitRawComment(const Twine &T, bool TabPrefix = true);
280 /// AddBlankLine - Emit a blank line to a .s file to pretty it up.
281 virtual void AddBlankLine() {}
285 /// @name Symbol & Section Management
288 /// getCurrentSection - Return the current section that the streamer is
289 /// emitting code to.
290 MCSectionSubPair getCurrentSection() const {
291 if (!SectionStack.empty())
292 return SectionStack.back().first;
293 return MCSectionSubPair();
296 /// getPreviousSection - Return the previous section that the streamer is
297 /// emitting code to.
298 MCSectionSubPair getPreviousSection() const {
299 if (!SectionStack.empty())
300 return SectionStack.back().second;
301 return MCSectionSubPair();
304 /// GetSymbolOrder - Returns an index to represent the order
305 /// a symbol was emitted in. (zero if we did not emit that symbol)
306 unsigned GetSymbolOrder(const MCSymbol *Sym) const {
307 return SymbolOrdering.lookup(Sym);
310 /// ChangeSection - Update streamer for a new active section.
312 /// This is called by PopSection and SwitchSection, if the current
314 virtual void ChangeSection(const MCSection *, const MCExpr *);
316 /// pushSection - Save the current and previous section on the
319 SectionStack.push_back(
320 std::make_pair(getCurrentSection(), getPreviousSection()));
323 /// popSection - Restore the current and previous section from
324 /// the section stack. Calls ChangeSection as needed.
326 /// Returns false if the stack was empty.
328 if (SectionStack.size() <= 1)
330 MCSectionSubPair oldSection = SectionStack.pop_back_val().first;
331 MCSectionSubPair curSection = SectionStack.back().first;
333 if (oldSection != curSection)
334 ChangeSection(curSection.first, curSection.second);
338 bool SubSection(const MCExpr *Subsection) {
339 if (SectionStack.empty())
342 SwitchSection(SectionStack.back().first.first, Subsection);
346 /// SwitchSection - Set the current section where code is being emitted to
347 /// @p Section. This is required to update CurSection.
349 /// This corresponds to assembler directives like .section, .text, etc.
350 virtual void SwitchSection(const MCSection *Section,
351 const MCExpr *Subsection = nullptr) {
352 assert(Section && "Cannot switch to a null section!");
353 MCSectionSubPair curSection = SectionStack.back().first;
354 SectionStack.back().second = curSection;
355 if (MCSectionSubPair(Section, Subsection) != curSection) {
356 SectionStack.back().first = MCSectionSubPair(Section, Subsection);
357 ChangeSection(Section, Subsection);
361 /// SwitchSectionNoChange - Set the current section where code is being
362 /// emitted to @p Section. This is required to update CurSection. This
363 /// version does not call ChangeSection.
364 void SwitchSectionNoChange(const MCSection *Section,
365 const MCExpr *Subsection = nullptr) {
366 assert(Section && "Cannot switch to a null section!");
367 MCSectionSubPair curSection = SectionStack.back().first;
368 SectionStack.back().second = curSection;
369 if (MCSectionSubPair(Section, Subsection) != curSection)
370 SectionStack.back().first = MCSectionSubPair(Section, Subsection);
373 /// Create the default sections and set the initial one.
374 virtual void InitSections(bool NoExecStack);
376 /// AssignSection - Sets the symbol's section.
378 /// Each emitted symbol will be tracked in the ordering table,
379 /// so we can sort on them later.
380 void AssignSection(MCSymbol *Symbol, const MCSection *Section);
382 /// EmitLabel - Emit a label for @p Symbol into the current section.
384 /// This corresponds to an assembler statement such as:
387 /// @param Symbol - The symbol to emit. A given symbol should only be
388 /// emitted as a label once, and symbols emitted as a label should never be
389 /// used in an assignment.
390 // FIXME: These emission are non-const because we mutate the symbol to
391 // add the section we're emitting it to later.
392 virtual void EmitLabel(MCSymbol *Symbol);
394 virtual void EmitEHSymAttributes(const MCSymbol *Symbol, MCSymbol *EHSymbol);
396 /// EmitAssemblerFlag - Note in the output the specified @p Flag.
397 virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
399 /// EmitLinkerOptions - Emit the given list @p Options of strings as linker
400 /// options into the output.
401 virtual void EmitLinkerOptions(ArrayRef<std::string> Kind) {}
403 /// EmitDataRegion - Note in the output the specified region @p Kind.
404 virtual void EmitDataRegion(MCDataRegionType Kind) {}
406 /// EmitVersionMin - Specify the MachO minimum deployment target version.
407 virtual void EmitVersionMin(MCVersionMinType, unsigned Major, unsigned Minor,
410 /// EmitThumbFunc - Note in the output that the specified @p Func is
411 /// a Thumb mode function (ARM target only).
412 virtual void EmitThumbFunc(MCSymbol *Func);
414 /// EmitAssignment - Emit an assignment of @p Value to @p Symbol.
416 /// This corresponds to an assembler statement such as:
419 /// The assignment generates no code, but has the side effect of binding the
420 /// value in the current context. For the assembly streamer, this prints the
421 /// binding into the .s file.
423 /// @param Symbol - The symbol being assigned to.
424 /// @param Value - The value for the symbol.
425 virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
427 /// EmitWeakReference - Emit an weak reference from @p Alias to @p Symbol.
429 /// This corresponds to an assembler statement such as:
430 /// .weakref alias, symbol
432 /// @param Alias - The alias that is being created.
433 /// @param Symbol - The symbol being aliased.
434 virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol);
436 /// EmitSymbolAttribute - Add the given @p Attribute to @p Symbol.
437 virtual bool EmitSymbolAttribute(MCSymbol *Symbol,
438 MCSymbolAttr Attribute) = 0;
440 /// EmitSymbolDesc - Set the @p DescValue for the @p Symbol.
442 /// @param Symbol - The symbol to have its n_desc field set.
443 /// @param DescValue - The value to set into the n_desc field.
444 virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
446 /// BeginCOFFSymbolDef - Start emitting COFF symbol definition
448 /// @param Symbol - The symbol to have its External & Type fields set.
449 virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol);
451 /// EmitCOFFSymbolStorageClass - Emit the storage class of the symbol.
453 /// @param StorageClass - The storage class the symbol should have.
454 virtual void EmitCOFFSymbolStorageClass(int StorageClass);
456 /// EmitCOFFSymbolType - Emit the type of the symbol.
458 /// @param Type - A COFF type identifier (see COFF::SymbolType in X86COFF.h)
459 virtual void EmitCOFFSymbolType(int Type);
461 /// EndCOFFSymbolDef - Marks the end of the symbol definition.
462 virtual void EndCOFFSymbolDef();
464 /// EmitCOFFSectionIndex - Emits a COFF section index.
466 /// @param Symbol - Symbol the section number relocation should point to.
467 virtual void EmitCOFFSectionIndex(MCSymbol const *Symbol);
469 /// EmitCOFFSecRel32 - Emits a COFF section relative relocation.
471 /// @param Symbol - Symbol the section relative relocation should point to.
472 virtual void EmitCOFFSecRel32(MCSymbol const *Symbol);
474 /// EmitELFSize - Emit an ELF .size directive.
476 /// This corresponds to an assembler statement such as:
477 /// .size symbol, expression
479 virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value);
481 /// \brief Emit a Linker Optimization Hint (LOH) directive.
482 /// \param Args - Arguments of the LOH.
483 virtual void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) {}
485 /// EmitCommonSymbol - Emit a common symbol.
487 /// @param Symbol - The common symbol to emit.
488 /// @param Size - The size of the common symbol.
489 /// @param ByteAlignment - The alignment of the symbol if
490 /// non-zero. This must be a power of 2.
491 virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
492 unsigned ByteAlignment) = 0;
494 /// EmitLocalCommonSymbol - Emit a local common (.lcomm) symbol.
496 /// @param Symbol - The common symbol to emit.
497 /// @param Size - The size of the common symbol.
498 /// @param ByteAlignment - The alignment of the common symbol in bytes.
499 virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
500 unsigned ByteAlignment);
502 /// EmitZerofill - Emit the zerofill section and an optional symbol.
504 /// @param Section - The zerofill section to create and or to put the symbol
505 /// @param Symbol - The zerofill symbol to emit, if non-NULL.
506 /// @param Size - The size of the zerofill symbol.
507 /// @param ByteAlignment - The alignment of the zerofill symbol if
508 /// non-zero. This must be a power of 2 on some targets.
509 virtual void EmitZerofill(const MCSection *Section,
510 MCSymbol *Symbol = nullptr, uint64_t Size = 0,
511 unsigned ByteAlignment = 0) = 0;
513 /// EmitTBSSSymbol - Emit a thread local bss (.tbss) symbol.
515 /// @param Section - The thread local common section.
516 /// @param Symbol - The thread local common symbol to emit.
517 /// @param Size - The size of the symbol.
518 /// @param ByteAlignment - The alignment of the thread local common symbol
519 /// if non-zero. This must be a power of 2 on some targets.
520 virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
521 uint64_t Size, unsigned ByteAlignment = 0);
524 /// @name Generating Data
527 /// EmitBytes - Emit the bytes in \p Data into the output.
529 /// This is used to implement assembler directives such as .byte, .ascii,
531 virtual void EmitBytes(StringRef Data);
533 /// EmitValue - Emit the expression @p Value into the output as a native
534 /// integer of the given @p Size bytes.
536 /// This is used to implement assembler directives such as .word, .quad,
539 /// @param Value - The value to emit.
540 /// @param Size - The size of the integer (in bytes) to emit. This must
541 /// match a native machine width.
542 /// @param Loc - The location of the expression for error reporting.
543 virtual void EmitValueImpl(const MCExpr *Value, unsigned Size,
544 const SMLoc &Loc = SMLoc());
546 void EmitValue(const MCExpr *Value, unsigned Size,
547 const SMLoc &Loc = SMLoc());
549 /// EmitIntValue - Special case of EmitValue that avoids the client having
550 /// to pass in a MCExpr for constant integers.
551 virtual void EmitIntValue(uint64_t Value, unsigned Size);
553 virtual void EmitULEB128Value(const MCExpr *Value);
555 virtual void EmitSLEB128Value(const MCExpr *Value);
557 /// EmitULEB128Value - Special case of EmitULEB128Value that avoids the
558 /// client having to pass in a MCExpr for constant integers.
559 void EmitULEB128IntValue(uint64_t Value, unsigned Padding = 0);
561 /// EmitSLEB128Value - Special case of EmitSLEB128Value that avoids the
562 /// client having to pass in a MCExpr for constant integers.
563 void EmitSLEB128IntValue(int64_t Value);
565 /// EmitSymbolValue - Special case of EmitValue that avoids the client
566 /// having to pass in a MCExpr for MCSymbols.
567 void EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
568 bool IsSectionRelative = false);
570 /// EmitGPRel64Value - Emit the expression @p Value into the output as a
571 /// gprel64 (64-bit GP relative) value.
573 /// This is used to implement assembler directives such as .gpdword on
574 /// targets that support them.
575 virtual void EmitGPRel64Value(const MCExpr *Value);
577 /// EmitGPRel32Value - Emit the expression @p Value into the output as a
578 /// gprel32 (32-bit GP relative) value.
580 /// This is used to implement assembler directives such as .gprel32 on
581 /// targets that support them.
582 virtual void EmitGPRel32Value(const MCExpr *Value);
584 /// EmitFill - Emit NumBytes bytes worth of the value specified by
585 /// FillValue. This implements directives such as '.space'.
586 virtual void EmitFill(uint64_t NumBytes, uint8_t FillValue);
588 /// \brief Emit NumBytes worth of zeros.
589 /// This function properly handles data in virtual sections.
590 virtual void EmitZeros(uint64_t NumBytes);
592 /// EmitValueToAlignment - Emit some number of copies of @p Value until
593 /// the byte alignment @p ByteAlignment is reached.
595 /// If the number of bytes need to emit for the alignment is not a multiple
596 /// of @p ValueSize, then the contents of the emitted fill bytes is
599 /// This used to implement the .align assembler directive.
601 /// @param ByteAlignment - The alignment to reach. This must be a power of
602 /// two on some targets.
603 /// @param Value - The value to use when filling bytes.
604 /// @param ValueSize - The size of the integer (in bytes) to emit for
605 /// @p Value. This must match a native machine width.
606 /// @param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
607 /// the alignment cannot be reached in this many bytes, no bytes are
609 virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
610 unsigned ValueSize = 1,
611 unsigned MaxBytesToEmit = 0);
613 /// EmitCodeAlignment - Emit nops until the byte alignment @p ByteAlignment
616 /// This used to align code where the alignment bytes may be executed. This
617 /// can emit different bytes for different sizes to optimize execution.
619 /// @param ByteAlignment - The alignment to reach. This must be a power of
620 /// two on some targets.
621 /// @param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
622 /// the alignment cannot be reached in this many bytes, no bytes are
624 virtual void EmitCodeAlignment(unsigned ByteAlignment,
625 unsigned MaxBytesToEmit = 0);
627 /// EmitValueToOffset - Emit some number of copies of @p Value until the
628 /// byte offset @p Offset is reached.
630 /// This is used to implement assembler directives such as .org.
632 /// @param Offset - The offset to reach. This may be an expression, but the
633 /// expression must be associated with the current section.
634 /// @param Value - The value to use when filling bytes.
635 /// @return false on success, true if the offset was invalid.
636 virtual bool EmitValueToOffset(const MCExpr *Offset,
637 unsigned char Value = 0);
641 /// EmitFileDirective - Switch to a new logical file. This is used to
642 /// implement the '.file "foo.c"' assembler directive.
643 virtual void EmitFileDirective(StringRef Filename);
645 /// Emit the "identifiers" directive. This implements the
646 /// '.ident "version foo"' assembler directive.
647 virtual void EmitIdent(StringRef IdentString) {}
649 /// EmitDwarfFileDirective - Associate a filename with a specified logical
650 /// file number. This implements the DWARF2 '.file 4 "foo.c"' assembler
652 virtual unsigned EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
656 /// EmitDwarfLocDirective - This implements the DWARF2
657 // '.loc fileno lineno ...' assembler directive.
658 virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
659 unsigned Column, unsigned Flags,
660 unsigned Isa, unsigned Discriminator,
663 virtual MCSymbol *getDwarfLineTableSymbol(unsigned CUID);
664 virtual void EmitCFISections(bool EH, bool Debug);
665 void EmitCFIStartProc(bool IsSimple);
666 void EmitCFIEndProc();
667 virtual void EmitCFIDefCfa(int64_t Register, int64_t Offset);
668 virtual void EmitCFIDefCfaOffset(int64_t Offset);
669 virtual void EmitCFIDefCfaRegister(int64_t Register);
670 virtual void EmitCFIOffset(int64_t Register, int64_t Offset);
671 virtual void EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding);
672 virtual void EmitCFILsda(const MCSymbol *Sym, unsigned Encoding);
673 virtual void EmitCFIRememberState();
674 virtual void EmitCFIRestoreState();
675 virtual void EmitCFISameValue(int64_t Register);
676 virtual void EmitCFIRestore(int64_t Register);
677 virtual void EmitCFIRelOffset(int64_t Register, int64_t Offset);
678 virtual void EmitCFIAdjustCfaOffset(int64_t Adjustment);
679 virtual void EmitCFIEscape(StringRef Values);
680 virtual void EmitCFISignalFrame();
681 virtual void EmitCFIUndefined(int64_t Register);
682 virtual void EmitCFIRegister(int64_t Register1, int64_t Register2);
683 virtual void EmitCFIWindowSave();
685 virtual void EmitWinCFIStartProc(const MCSymbol *Symbol);
686 virtual void EmitWinCFIEndProc();
687 virtual void EmitWinCFIStartChained();
688 virtual void EmitWinCFIEndChained();
689 virtual void EmitWinCFIPushReg(unsigned Register);
690 virtual void EmitWinCFISetFrame(unsigned Register, unsigned Offset);
691 virtual void EmitWinCFIAllocStack(unsigned Size);
692 virtual void EmitWinCFISaveReg(unsigned Register, unsigned Offset);
693 virtual void EmitWinCFISaveXMM(unsigned Register, unsigned Offset);
694 virtual void EmitWinCFIPushFrame(bool Code);
695 virtual void EmitWinCFIEndProlog();
697 virtual void EmitWinEHHandler(const MCSymbol *Sym, bool Unwind, bool Except);
698 virtual void EmitWinEHHandlerData();
700 /// EmitInstruction - Emit the given @p Instruction into the current
702 virtual void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI);
704 /// \brief Set the bundle alignment mode from now on in the section.
705 /// The argument is the power of 2 to which the alignment is set. The
706 /// value 0 means turn the bundle alignment off.
707 virtual void EmitBundleAlignMode(unsigned AlignPow2);
709 /// \brief The following instructions are a bundle-locked group.
711 /// \param AlignToEnd - If true, the bundle-locked group will be aligned to
712 /// the end of a bundle.
713 virtual void EmitBundleLock(bool AlignToEnd);
715 /// \brief Ends a bundle-locked group.
716 virtual void EmitBundleUnlock();
718 /// EmitRawText - If this file is backed by a assembly streamer, this dumps
719 /// the specified string in the output .s file. This capability is
720 /// indicated by the hasRawTextSupport() predicate. By default this aborts.
721 void EmitRawText(const Twine &String);
723 /// Flush - Causes any cached state to be written out.
724 virtual void Flush() {}
726 /// FinishImpl - Streamer specific finalization.
727 virtual void FinishImpl();
728 /// Finish - Finish emission of machine code.
731 virtual bool mayHaveInstructions() const { return true; }
734 /// createNullStreamer - Create a dummy machine code streamer, which does
735 /// nothing. This is useful for timing the assembler front end.
736 MCStreamer *createNullStreamer(MCContext &Ctx);
738 /// createAsmStreamer - Create a machine code streamer which will print out
739 /// assembly for the native target, suitable for compiling with a native
742 /// \param InstPrint - If given, the instruction printer to use. If not given
743 /// the MCInst representation will be printed. This method takes ownership of
746 /// \param CE - If given, a code emitter to use to show the instruction
747 /// encoding inline with the assembly. This method takes ownership of \p CE.
749 /// \param TAB - If given, a target asm backend to use to show the fixup
750 /// information in conjunction with encoding information. This method takes
751 /// ownership of \p TAB.
753 /// \param ShowInst - Whether to show the MCInst representation inline with
755 MCStreamer *createAsmStreamer(MCContext &Ctx, formatted_raw_ostream &OS,
756 bool isVerboseAsm, bool useDwarfDirectory,
757 MCInstPrinter *InstPrint, MCCodeEmitter *CE,
758 MCAsmBackend *TAB, bool ShowInst);
760 /// createMachOStreamer - Create a machine code streamer which will generate
761 /// Mach-O format object files.
763 /// Takes ownership of \p TAB and \p CE.
764 MCStreamer *createMachOStreamer(MCContext &Ctx, MCAsmBackend &TAB,
765 raw_ostream &OS, MCCodeEmitter *CE,
766 bool RelaxAll = false,
767 bool LabelSections = false);
769 /// createELFStreamer - Create a machine code streamer which will generate
770 /// ELF format object files.
771 MCStreamer *createELFStreamer(MCContext &Ctx, MCAsmBackend &TAB,
772 raw_ostream &OS, MCCodeEmitter *CE,
775 } // end namespace llvm