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/MCWin64EH.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 /// * FooTargetAsmSreamer : 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 FooTargetAsmSreamer 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 FooTargetAsmSreamer and FooTargetELFStreamer should *never*
70 /// be treated differently. Callers should always talk to a FooTargetStreamer.
71 class MCTargetStreamer {
76 MCTargetStreamer(MCStreamer &S);
77 virtual ~MCTargetStreamer();
79 const MCStreamer &getStreamer() { return Streamer; }
81 // Allow a target to add behavior to the EmitLabel of MCStreamer.
82 virtual void emitLabel(MCSymbol *Symbol);
83 // Allow a target to add behavior to the emitAssignment of MCStreamer.
84 virtual void emitAssignment(MCSymbol *Symbol, const MCExpr *Value);
86 virtual void finish();
89 class AArch64TargetStreamer : public MCTargetStreamer {
91 AArch64TargetStreamer(MCStreamer &S);
92 ~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 *);
102 /// Callback used to implemnt the .ltorg directive.
103 /// Emit contents of constant pool for the current section.
104 void emitCurrentConstantPool();
107 std::unique_ptr<AssemblerConstantPools> ConstantPools;
110 // FIXME: declared here because it is used from
111 // lib/CodeGen/AsmPrinter/ARMException.cpp.
112 class ARMTargetStreamer : public MCTargetStreamer {
114 ARMTargetStreamer(MCStreamer &S);
115 ~ARMTargetStreamer();
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,
125 virtual void emitMovSP(unsigned Reg, int64_t Offset = 0);
126 virtual void emitPad(int64_t Offset);
127 virtual void emitRegSave(const SmallVectorImpl<unsigned> &RegList,
129 virtual void emitUnwindRaw(int64_t StackOffset,
130 const SmallVectorImpl<uint8_t> &Opcodes);
132 virtual void switchVendor(StringRef Vendor);
133 virtual void emitAttribute(unsigned Attribute, unsigned Value);
134 virtual void emitTextAttribute(unsigned Attribute, StringRef String);
135 virtual void emitIntTextAttribute(unsigned Attribute, unsigned IntValue,
136 StringRef StringValue = "");
137 virtual void emitFPU(unsigned FPU);
138 virtual void emitArch(unsigned Arch);
139 virtual void emitObjectArch(unsigned Arch);
140 virtual void finishAttributeSection();
141 virtual void emitInst(uint32_t Inst, char Suffix = '\0');
143 virtual void AnnotateTLSDescriptorSequence(const MCSymbolRefExpr *SRE);
145 virtual void emitThumbSet(MCSymbol *Symbol, const MCExpr *Value);
147 void finish() override;
149 /// Callback used to implement the ldr= pseudo.
150 /// Add a new entry to the constant pool for the current section and return an
151 /// MCExpr that can be used to refer to the constant pool location.
152 const MCExpr *addConstantPoolEntry(const MCExpr *);
154 /// Callback used to implemnt the .ltorg directive.
155 /// Emit contents of constant pool for the current section.
156 void emitCurrentConstantPool();
159 std::unique_ptr<AssemblerConstantPools> ConstantPools;
162 /// MCStreamer - Streaming machine code generation interface. This interface
163 /// is intended to provide a programatic interface that is very similar to the
164 /// level that an assembler .s file provides. It has callbacks to emit bytes,
165 /// handle directives, etc. The implementation of this interface retains
166 /// state to know what the current section is etc.
168 /// There are multiple implementations of this interface: one for writing out
169 /// a .s file, and implementations that write out .o files of various formats.
173 std::unique_ptr<MCTargetStreamer> TargetStreamer;
175 MCStreamer(const MCStreamer &) LLVM_DELETED_FUNCTION;
176 MCStreamer &operator=(const MCStreamer &) LLVM_DELETED_FUNCTION;
178 std::vector<MCDwarfFrameInfo> FrameInfos;
179 MCDwarfFrameInfo *getCurrentFrameInfo();
180 MCSymbol *EmitCFICommon();
181 void EnsureValidFrame();
183 std::vector<MCWin64EHUnwindInfo *> W64UnwindInfos;
184 MCWin64EHUnwindInfo *CurrentW64UnwindInfo;
185 void setCurrentW64UnwindInfo(MCWin64EHUnwindInfo *Frame);
186 void EnsureValidW64UnwindInfo();
188 // SymbolOrdering - Tracks an index to represent the order
189 // a symbol was emitted in. Zero means we did not emit that symbol.
190 DenseMap<const MCSymbol *, unsigned> SymbolOrdering;
192 /// SectionStack - This is stack of current and previous section
193 /// values saved by PushSection.
194 SmallVector<std::pair<MCSectionSubPair, MCSectionSubPair>, 4> SectionStack;
197 MCStreamer(MCContext &Ctx);
199 const MCExpr *BuildSymbolDiff(MCContext &Context, const MCSymbol *A,
202 const MCExpr *ForceExpAbs(const MCExpr *Expr);
204 void RecordProcStart(MCDwarfFrameInfo &Frame);
205 virtual void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame);
206 void RecordProcEnd(MCDwarfFrameInfo &Frame);
207 virtual void EmitCFIEndProcImpl(MCDwarfFrameInfo &CurFrame);
209 MCWin64EHUnwindInfo *getCurrentW64UnwindInfo() {
210 return CurrentW64UnwindInfo;
212 void EmitW64Tables();
214 virtual void EmitRawTextImpl(StringRef String);
217 virtual ~MCStreamer();
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 FrameInfos.size(); }
235 const MCDwarfFrameInfo &getFrameInfo(unsigned i) { return FrameInfos[i]; }
237 ArrayRef<MCDwarfFrameInfo> getFrameInfos() const { return FrameInfos; }
239 unsigned getNumW64UnwindInfos() { return W64UnwindInfos.size(); }
241 MCWin64EHUnwindInfo &getW64UnwindInfo(unsigned i) {
242 return *W64UnwindInfos[i];
245 void generateCompactUnwindEncodings(MCAsmBackend *MAB);
247 /// @name Assembly File Formatting.
250 /// isVerboseAsm - Return true if this streamer supports verbose assembly
251 /// and if it is enabled.
252 virtual bool isVerboseAsm() const { return false; }
254 /// hasRawTextSupport - Return true if this asm streamer supports emitting
255 /// unformatted text to the .s file with EmitRawText.
256 virtual bool hasRawTextSupport() const { return false; }
258 /// Is the integrated assembler required for this streamer to function
260 virtual bool isIntegratedAssemblerRequired() const { return false; }
262 /// AddComment - Add a comment that can be emitted to the generated .s
263 /// file if applicable as a QoI issue to make the output of the compiler
264 /// more readable. This only affects the MCAsmStreamer, and only when
265 /// verbose assembly output is enabled.
267 /// If the comment includes embedded \n's, they will each get the comment
268 /// prefix as appropriate. The added comment should not end with a \n.
269 virtual void AddComment(const Twine &T) {}
271 /// GetCommentOS - Return a raw_ostream that comments can be written to.
272 /// Unlike AddComment, you are required to terminate comments with \n if you
274 virtual raw_ostream &GetCommentOS();
276 /// Print T and prefix it with the comment string (normally #) and optionally
277 /// a tab. This prints the comment immediately, not at the end of the
278 /// current line. It is basically a safe version of EmitRawText: since it
279 /// only prints comments, the object streamer ignores it instead of asserting.
280 virtual void emitRawComment(const Twine &T, bool TabPrefix = true);
282 /// AddBlankLine - Emit a blank line to a .s file to pretty it up.
283 virtual void AddBlankLine() {}
287 /// @name Symbol & Section Management
290 /// getCurrentSection - Return the current section that the streamer is
291 /// emitting code to.
292 MCSectionSubPair getCurrentSection() const {
293 if (!SectionStack.empty())
294 return SectionStack.back().first;
295 return MCSectionSubPair();
298 /// getPreviousSection - Return the previous section that the streamer is
299 /// emitting code to.
300 MCSectionSubPair getPreviousSection() const {
301 if (!SectionStack.empty())
302 return SectionStack.back().second;
303 return MCSectionSubPair();
306 /// GetSymbolOrder - Returns an index to represent the order
307 /// a symbol was emitted in. (zero if we did not emit that symbol)
308 unsigned GetSymbolOrder(const MCSymbol *Sym) const {
309 return SymbolOrdering.lookup(Sym);
312 /// ChangeSection - Update streamer for a new active section.
314 /// This is called by PopSection and SwitchSection, if the current
316 virtual void ChangeSection(const MCSection *, const MCExpr *) = 0;
318 /// pushSection - Save the current and previous section on the
321 SectionStack.push_back(
322 std::make_pair(getCurrentSection(), getPreviousSection()));
325 /// popSection - Restore the current and previous section from
326 /// the section stack. Calls ChangeSection as needed.
328 /// Returns false if the stack was empty.
330 if (SectionStack.size() <= 1)
332 MCSectionSubPair oldSection = SectionStack.pop_back_val().first;
333 MCSectionSubPair curSection = SectionStack.back().first;
335 if (oldSection != curSection)
336 ChangeSection(curSection.first, curSection.second);
340 bool SubSection(const MCExpr *Subsection) {
341 if (SectionStack.empty())
344 SwitchSection(SectionStack.back().first.first, Subsection);
348 /// SwitchSection - Set the current section where code is being emitted to
349 /// @p Section. This is required to update CurSection.
351 /// This corresponds to assembler directives like .section, .text, etc.
352 void SwitchSection(const MCSection *Section,
353 const MCExpr *Subsection = nullptr) {
354 assert(Section && "Cannot switch to a null section!");
355 MCSectionSubPair curSection = SectionStack.back().first;
356 SectionStack.back().second = curSection;
357 if (MCSectionSubPair(Section, Subsection) != curSection) {
358 SectionStack.back().first = MCSectionSubPair(Section, Subsection);
359 ChangeSection(Section, Subsection);
363 /// SwitchSectionNoChange - Set the current section where code is being
364 /// emitted to @p Section. This is required to update CurSection. This
365 /// version does not call ChangeSection.
366 void SwitchSectionNoChange(const MCSection *Section,
367 const MCExpr *Subsection = nullptr) {
368 assert(Section && "Cannot switch to a null section!");
369 MCSectionSubPair curSection = SectionStack.back().first;
370 SectionStack.back().second = curSection;
371 if (MCSectionSubPair(Section, Subsection) != curSection)
372 SectionStack.back().first = MCSectionSubPair(Section, Subsection);
375 /// Create the default sections and set the initial one.
376 virtual void InitSections();
378 /// AssignSection - Sets the symbol's section.
380 /// Each emitted symbol will be tracked in the ordering table,
381 /// so we can sort on them later.
382 void AssignSection(MCSymbol *Symbol, const MCSection *Section);
384 /// EmitLabel - Emit a label for @p Symbol into the current section.
386 /// This corresponds to an assembler statement such as:
389 /// @param Symbol - The symbol to emit. A given symbol should only be
390 /// emitted as a label once, and symbols emitted as a label should never be
391 /// used in an assignment.
392 // FIXME: These emission are non-const because we mutate the symbol to
393 // add the section we're emitting it to later.
394 virtual void EmitLabel(MCSymbol *Symbol);
396 virtual void EmitDebugLabel(MCSymbol *Symbol);
398 virtual void EmitEHSymAttributes(const MCSymbol *Symbol, MCSymbol *EHSymbol);
400 /// EmitAssemblerFlag - Note in the output the specified @p Flag.
401 virtual void EmitAssemblerFlag(MCAssemblerFlag Flag) = 0;
403 /// EmitLinkerOptions - Emit the given list @p Options of strings as linker
404 /// options into the output.
405 virtual void EmitLinkerOptions(ArrayRef<std::string> Kind) {}
407 /// EmitDataRegion - Note in the output the specified region @p Kind.
408 virtual void EmitDataRegion(MCDataRegionType Kind) {}
410 /// EmitVersionMin - Specify the MachO minimum deployment target version.
411 virtual void EmitVersionMin(MCVersionMinType, unsigned Major, unsigned Minor,
414 /// EmitThumbFunc - Note in the output that the specified @p Func is
415 /// a Thumb mode function (ARM target only).
416 virtual void EmitThumbFunc(MCSymbol *Func) = 0;
418 /// EmitAssignment - Emit an assignment of @p Value to @p Symbol.
420 /// This corresponds to an assembler statement such as:
423 /// The assignment generates no code, but has the side effect of binding the
424 /// value in the current context. For the assembly streamer, this prints the
425 /// binding into the .s file.
427 /// @param Symbol - The symbol being assigned to.
428 /// @param Value - The value for the symbol.
429 virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value);
431 /// EmitWeakReference - Emit an weak reference from @p Alias to @p Symbol.
433 /// This corresponds to an assembler statement such as:
434 /// .weakref alias, symbol
436 /// @param Alias - The alias that is being created.
437 /// @param Symbol - The symbol being aliased.
438 virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) = 0;
440 /// EmitSymbolAttribute - Add the given @p Attribute to @p Symbol.
441 virtual bool EmitSymbolAttribute(MCSymbol *Symbol,
442 MCSymbolAttr Attribute) = 0;
444 /// EmitSymbolDesc - Set the @p DescValue for the @p Symbol.
446 /// @param Symbol - The symbol to have its n_desc field set.
447 /// @param DescValue - The value to set into the n_desc field.
448 virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) = 0;
450 /// BeginCOFFSymbolDef - Start emitting COFF symbol definition
452 /// @param Symbol - The symbol to have its External & Type fields set.
453 virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol) = 0;
455 /// EmitCOFFSymbolStorageClass - Emit the storage class of the symbol.
457 /// @param StorageClass - The storage class the symbol should have.
458 virtual void EmitCOFFSymbolStorageClass(int StorageClass) = 0;
460 /// EmitCOFFSymbolType - Emit the type of the symbol.
462 /// @param Type - A COFF type identifier (see COFF::SymbolType in X86COFF.h)
463 virtual void EmitCOFFSymbolType(int Type) = 0;
465 /// EndCOFFSymbolDef - Marks the end of the symbol definition.
466 virtual void EndCOFFSymbolDef() = 0;
468 /// EmitCOFFSectionIndex - Emits a COFF section index.
470 /// @param Symbol - Symbol the section number relocation should point to.
471 virtual void EmitCOFFSectionIndex(MCSymbol const *Symbol);
473 /// EmitCOFFSecRel32 - Emits a COFF section relative relocation.
475 /// @param Symbol - Symbol the section relative relocation should point to.
476 virtual void EmitCOFFSecRel32(MCSymbol const *Symbol);
478 /// EmitELFSize - Emit an ELF .size directive.
480 /// This corresponds to an assembler statement such as:
481 /// .size symbol, expression
483 virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) = 0;
485 /// \brief Emit a Linker Optimization Hint (LOH) directive.
486 /// \param Args - Arguments of the LOH.
487 virtual void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) {}
489 /// EmitCommonSymbol - Emit a common symbol.
491 /// @param Symbol - The common symbol to emit.
492 /// @param Size - The size of the common symbol.
493 /// @param ByteAlignment - The alignment of the symbol if
494 /// non-zero. This must be a power of 2.
495 virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
496 unsigned ByteAlignment) = 0;
498 /// EmitLocalCommonSymbol - Emit a local common (.lcomm) symbol.
500 /// @param Symbol - The common symbol to emit.
501 /// @param Size - The size of the common symbol.
502 /// @param ByteAlignment - The alignment of the common symbol in bytes.
503 virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
504 unsigned ByteAlignment) = 0;
506 /// EmitZerofill - Emit the zerofill section and an optional symbol.
508 /// @param Section - The zerofill section to create and or to put the symbol
509 /// @param Symbol - The zerofill symbol to emit, if non-NULL.
510 /// @param Size - The size of the zerofill symbol.
511 /// @param ByteAlignment - The alignment of the zerofill symbol if
512 /// non-zero. This must be a power of 2 on some targets.
513 virtual void EmitZerofill(const MCSection *Section,
514 MCSymbol *Symbol = nullptr, uint64_t Size = 0,
515 unsigned ByteAlignment = 0) = 0;
517 /// EmitTBSSSymbol - Emit a thread local bss (.tbss) symbol.
519 /// @param Section - The thread local common section.
520 /// @param Symbol - The thread local common symbol to emit.
521 /// @param Size - The size of the symbol.
522 /// @param ByteAlignment - The alignment of the thread local common symbol
523 /// if non-zero. This must be a power of 2 on some targets.
524 virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
525 uint64_t Size, unsigned ByteAlignment = 0) = 0;
528 /// @name Generating Data
531 /// EmitBytes - Emit the bytes in \p Data into the output.
533 /// This is used to implement assembler directives such as .byte, .ascii,
535 virtual void EmitBytes(StringRef Data) = 0;
537 /// EmitValue - Emit the expression @p Value into the output as a native
538 /// integer of the given @p Size bytes.
540 /// This is used to implement assembler directives such as .word, .quad,
543 /// @param Value - The value to emit.
544 /// @param Size - The size of the integer (in bytes) to emit. This must
545 /// match a native machine width.
546 /// @param Loc - The location of the expression for error reporting.
547 virtual void EmitValueImpl(const MCExpr *Value, unsigned Size,
548 const SMLoc &Loc = SMLoc()) = 0;
550 void EmitValue(const MCExpr *Value, unsigned Size,
551 const SMLoc &Loc = SMLoc());
553 /// EmitIntValue - Special case of EmitValue that avoids the client having
554 /// to pass in a MCExpr for constant integers.
555 virtual void EmitIntValue(uint64_t Value, unsigned Size);
557 /// EmitAbsValue - Emit the Value, but try to avoid relocations. On MachO
558 /// this is done by producing
561 void EmitAbsValue(const MCExpr *Value, unsigned Size);
563 virtual void EmitULEB128Value(const MCExpr *Value) = 0;
565 virtual void EmitSLEB128Value(const MCExpr *Value) = 0;
567 /// EmitULEB128Value - Special case of EmitULEB128Value that avoids the
568 /// client having to pass in a MCExpr for constant integers.
569 void EmitULEB128IntValue(uint64_t Value, unsigned Padding = 0);
571 /// EmitSLEB128Value - Special case of EmitSLEB128Value that avoids the
572 /// client having to pass in a MCExpr for constant integers.
573 void EmitSLEB128IntValue(int64_t Value);
575 /// EmitSymbolValue - Special case of EmitValue that avoids the client
576 /// having to pass in a MCExpr for MCSymbols.
577 void EmitSymbolValue(const MCSymbol *Sym, unsigned Size);
579 /// EmitGPRel64Value - Emit the expression @p Value into the output as a
580 /// gprel64 (64-bit GP relative) value.
582 /// This is used to implement assembler directives such as .gpdword on
583 /// targets that support them.
584 virtual void EmitGPRel64Value(const MCExpr *Value);
586 /// EmitGPRel32Value - Emit the expression @p Value into the output as a
587 /// gprel32 (32-bit GP relative) value.
589 /// This is used to implement assembler directives such as .gprel32 on
590 /// targets that support them.
591 virtual void EmitGPRel32Value(const MCExpr *Value);
593 /// EmitFill - Emit NumBytes bytes worth of the value specified by
594 /// FillValue. This implements directives such as '.space'.
595 virtual void EmitFill(uint64_t NumBytes, uint8_t FillValue);
597 /// \brief Emit NumBytes worth of zeros.
598 /// This function properly handles data in virtual sections.
599 virtual void EmitZeros(uint64_t NumBytes);
601 /// EmitValueToAlignment - Emit some number of copies of @p Value until
602 /// the byte alignment @p ByteAlignment is reached.
604 /// If the number of bytes need to emit for the alignment is not a multiple
605 /// of @p ValueSize, then the contents of the emitted fill bytes is
608 /// This used to implement the .align assembler directive.
610 /// @param ByteAlignment - The alignment to reach. This must be a power of
611 /// two on some targets.
612 /// @param Value - The value to use when filling bytes.
613 /// @param ValueSize - The size of the integer (in bytes) to emit for
614 /// @p Value. This must match a native machine width.
615 /// @param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
616 /// the alignment cannot be reached in this many bytes, no bytes are
618 virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
619 unsigned ValueSize = 1,
620 unsigned MaxBytesToEmit = 0) = 0;
622 /// EmitCodeAlignment - Emit nops until the byte alignment @p ByteAlignment
625 /// This used to align code where the alignment bytes may be executed. This
626 /// can emit different bytes for different sizes to optimize execution.
628 /// @param ByteAlignment - The alignment to reach. This must be a power of
629 /// two on some targets.
630 /// @param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If
631 /// the alignment cannot be reached in this many bytes, no bytes are
633 virtual void EmitCodeAlignment(unsigned ByteAlignment,
634 unsigned MaxBytesToEmit = 0) = 0;
636 /// EmitValueToOffset - Emit some number of copies of @p Value until the
637 /// byte offset @p Offset is reached.
639 /// This is used to implement assembler directives such as .org.
641 /// @param Offset - The offset to reach. This may be an expression, but the
642 /// expression must be associated with the current section.
643 /// @param Value - The value to use when filling bytes.
644 /// @return false on success, true if the offset was invalid.
645 virtual bool EmitValueToOffset(const MCExpr *Offset,
646 unsigned char Value = 0) = 0;
650 /// EmitFileDirective - Switch to a new logical file. This is used to
651 /// implement the '.file "foo.c"' assembler directive.
652 virtual void EmitFileDirective(StringRef Filename) = 0;
654 /// Emit the "identifiers" directive. This implements the
655 /// '.ident "version foo"' assembler directive.
656 virtual void EmitIdent(StringRef IdentString) {}
658 /// EmitDwarfFileDirective - Associate a filename with a specified logical
659 /// file number. This implements the DWARF2 '.file 4 "foo.c"' assembler
661 virtual unsigned EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
665 /// EmitDwarfLocDirective - This implements the DWARF2
666 // '.loc fileno lineno ...' assembler directive.
667 virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
668 unsigned Column, unsigned Flags,
669 unsigned Isa, unsigned Discriminator,
672 virtual MCSymbol *getDwarfLineTableSymbol(unsigned CUID);
674 void EmitDwarfSetLineAddr(int64_t LineDelta, const MCSymbol *Label,
677 virtual void EmitCompactUnwindEncoding(uint32_t CompactUnwindEncoding);
678 virtual void EmitCFISections(bool EH, bool Debug);
679 void EmitCFIStartProc(bool IsSimple);
680 void EmitCFIEndProc();
681 virtual void EmitCFIDefCfa(int64_t Register, int64_t Offset);
682 virtual void EmitCFIDefCfaOffset(int64_t Offset);
683 virtual void EmitCFIDefCfaRegister(int64_t Register);
684 virtual void EmitCFIOffset(int64_t Register, int64_t Offset);
685 virtual void EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding);
686 virtual void EmitCFILsda(const MCSymbol *Sym, unsigned Encoding);
687 virtual void EmitCFIRememberState();
688 virtual void EmitCFIRestoreState();
689 virtual void EmitCFISameValue(int64_t Register);
690 virtual void EmitCFIRestore(int64_t Register);
691 virtual void EmitCFIRelOffset(int64_t Register, int64_t Offset);
692 virtual void EmitCFIAdjustCfaOffset(int64_t Adjustment);
693 virtual void EmitCFIEscape(StringRef Values);
694 virtual void EmitCFISignalFrame();
695 virtual void EmitCFIUndefined(int64_t Register);
696 virtual void EmitCFIRegister(int64_t Register1, int64_t Register2);
697 virtual void EmitCFIWindowSave();
699 virtual void EmitWin64EHStartProc(const MCSymbol *Symbol);
700 virtual void EmitWin64EHEndProc();
701 virtual void EmitWin64EHStartChained();
702 virtual void EmitWin64EHEndChained();
703 virtual void EmitWin64EHHandler(const MCSymbol *Sym, bool Unwind,
705 virtual void EmitWin64EHHandlerData();
706 virtual void EmitWin64EHPushReg(unsigned Register);
707 virtual void EmitWin64EHSetFrame(unsigned Register, unsigned Offset);
708 virtual void EmitWin64EHAllocStack(unsigned Size);
709 virtual void EmitWin64EHSaveReg(unsigned Register, unsigned Offset);
710 virtual void EmitWin64EHSaveXMM(unsigned Register, unsigned Offset);
711 virtual void EmitWin64EHPushFrame(bool Code);
712 virtual void EmitWin64EHEndProlog();
714 /// EmitInstruction - Emit the given @p Instruction into the current
716 virtual void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) = 0;
718 /// \brief Set the bundle alignment mode from now on in the section.
719 /// The argument is the power of 2 to which the alignment is set. The
720 /// value 0 means turn the bundle alignment off.
721 virtual void EmitBundleAlignMode(unsigned AlignPow2) = 0;
723 /// \brief The following instructions are a bundle-locked group.
725 /// \param AlignToEnd - If true, the bundle-locked group will be aligned to
726 /// the end of a bundle.
727 virtual void EmitBundleLock(bool AlignToEnd) = 0;
729 /// \brief Ends a bundle-locked group.
730 virtual void EmitBundleUnlock() = 0;
732 /// EmitRawText - If this file is backed by a assembly streamer, this dumps
733 /// the specified string in the output .s file. This capability is
734 /// indicated by the hasRawTextSupport() predicate. By default this aborts.
735 void EmitRawText(const Twine &String);
737 /// Flush - Causes any cached state to be written out.
738 virtual void Flush() {}
740 /// FinishImpl - Streamer specific finalization.
741 virtual void FinishImpl() = 0;
742 /// Finish - Finish emission of machine code.
745 virtual bool mayHaveInstructions() const { return true; }
748 /// createNullStreamer - Create a dummy machine code streamer, which does
749 /// nothing. This is useful for timing the assembler front end.
750 MCStreamer *createNullStreamer(MCContext &Ctx);
752 /// createAsmStreamer - Create a machine code streamer which will print out
753 /// assembly for the native target, suitable for compiling with a native
756 /// \param InstPrint - If given, the instruction printer to use. If not given
757 /// the MCInst representation will be printed. This method takes ownership of
760 /// \param CE - If given, a code emitter to use to show the instruction
761 /// encoding inline with the assembly. This method takes ownership of \p CE.
763 /// \param TAB - If given, a target asm backend to use to show the fixup
764 /// information in conjunction with encoding information. This method takes
765 /// ownership of \p TAB.
767 /// \param ShowInst - Whether to show the MCInst representation inline with
769 MCStreamer *createAsmStreamer(MCContext &Ctx, formatted_raw_ostream &OS,
770 bool isVerboseAsm, bool useDwarfDirectory,
771 MCInstPrinter *InstPrint, MCCodeEmitter *CE,
772 MCAsmBackend *TAB, bool ShowInst);
774 /// createMachOStreamer - Create a machine code streamer which will generate
775 /// Mach-O format object files.
777 /// Takes ownership of \p TAB and \p CE.
778 MCStreamer *createMachOStreamer(MCContext &Ctx, MCAsmBackend &TAB,
779 raw_ostream &OS, MCCodeEmitter *CE,
780 bool RelaxAll = false,
781 bool LabelSections = false);
783 /// createELFStreamer - Create a machine code streamer which will generate
784 /// ELF format object files.
785 MCStreamer *createELFStreamer(MCContext &Ctx, MCAsmBackend &TAB,
786 raw_ostream &OS, MCCodeEmitter *CE, bool RelaxAll,
789 } // end namespace llvm