1 //===-- llvm/MC/WinCOFFStreamer.cpp -----------------------------*- 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 contains an implementation of a Win32 COFF object file streamer.
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "WinCOFFStreamer"
16 #include "llvm/MC/MCStreamer.h"
17 #include "llvm/MC/MCAsmBackend.h"
18 #include "llvm/MC/MCAsmLayout.h"
19 #include "llvm/MC/MCAssembler.h"
20 #include "llvm/MC/MCCodeEmitter.h"
21 #include "llvm/MC/MCContext.h"
22 #include "llvm/MC/MCExpr.h"
23 #include "llvm/MC/MCObjectFileInfo.h"
24 #include "llvm/MC/MCObjectStreamer.h"
25 #include "llvm/MC/MCSection.h"
26 #include "llvm/MC/MCSectionCOFF.h"
27 #include "llvm/MC/MCSymbol.h"
28 #include "llvm/MC/MCValue.h"
29 #include "llvm/MC/MCWin64EH.h"
30 #include "llvm/Support/COFF.h"
31 #include "llvm/Support/Debug.h"
32 #include "llvm/Support/ErrorHandling.h"
33 #include "llvm/Support/TargetRegistry.h"
34 #include "llvm/Support/raw_ostream.h"
39 class WinCOFFStreamer : public MCObjectStreamer {
41 MCSymbol const *CurSymbol;
43 WinCOFFStreamer(MCContext &Context,
48 void AddCommonSymbol(MCSymbol *Symbol, uint64_t Size,
49 unsigned ByteAlignment, bool External);
51 // MCStreamer interface
53 virtual void InitSections();
54 virtual void InitToTextSection();
55 virtual void EmitLabel(MCSymbol *Symbol);
56 virtual void EmitDebugLabel(MCSymbol *Symbol);
57 virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
58 virtual void EmitThumbFunc(MCSymbol *Func);
59 virtual bool EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute);
60 virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
61 virtual void BeginCOFFSymbolDef(MCSymbol const *Symbol);
62 virtual void EmitCOFFSymbolStorageClass(int StorageClass);
63 virtual void EmitCOFFSymbolType(int Type);
64 virtual void EndCOFFSymbolDef();
65 virtual void EmitCOFFSectionIndex(MCSymbol const *Symbol);
66 virtual void EmitCOFFSecRel32(MCSymbol const *Symbol);
67 virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value);
68 virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
69 unsigned ByteAlignment);
70 virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
71 unsigned ByteAlignment);
72 virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
73 uint64_t Size,unsigned ByteAlignment);
74 virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
75 uint64_t Size, unsigned ByteAlignment);
76 virtual void EmitFileDirective(StringRef Filename);
77 virtual void EmitIdent(StringRef IdentString);
78 virtual void EmitWin64EHHandlerData();
79 virtual void FinishImpl();
82 virtual void EmitInstToData(const MCInst &Inst) {
83 MCDataFragment *DF = getOrCreateDataFragment();
85 SmallVector<MCFixup, 4> Fixups;
86 SmallString<256> Code;
87 raw_svector_ostream VecOS(Code);
88 getAssembler().getEmitter().EncodeInstruction(Inst, VecOS, Fixups);
91 // Add the fixups and data.
92 for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
93 Fixups[i].setOffset(Fixups[i].getOffset() + DF->getContents().size());
94 DF->getFixups().push_back(Fixups[i]);
96 DF->getContents().append(Code.begin(), Code.end());
99 const MCSection *getSectionText() {
100 return getContext().getObjectFileInfo()->getTextSection();
103 const MCSection *getSectionData() {
104 return getContext().getObjectFileInfo()->getDataSection();
107 const MCSection *getSectionBSS() {
108 return getContext().getObjectFileInfo()->getBSSSection();
111 void SetSectionText() {
112 SwitchSection(getSectionText());
113 EmitCodeAlignment(4, 0);
116 void SetSectionData() {
117 SwitchSection(getSectionData());
118 EmitCodeAlignment(4, 0);
121 void SetSectionBSS() {
122 SwitchSection(getSectionBSS());
123 EmitCodeAlignment(4, 0);
126 } // end anonymous namespace.
128 WinCOFFStreamer::WinCOFFStreamer(MCContext &Context, MCAsmBackend &MAB,
129 MCCodeEmitter &CE, raw_ostream &OS)
130 : MCObjectStreamer(Context, 0, MAB, OS, &CE), CurSymbol(NULL) {}
132 void WinCOFFStreamer::AddCommonSymbol(MCSymbol *Symbol, uint64_t Size,
133 unsigned ByteAlignment, bool External) {
134 assert(!Symbol->isInSection() && "Symbol must not already have a section!");
136 const MCSection *Section = getSectionBSS();
137 MCSectionData &SectionData = getAssembler().getOrCreateSectionData(*Section);
138 if (SectionData.getAlignment() < ByteAlignment)
139 SectionData.setAlignment(ByteAlignment);
141 MCSymbolData &SymbolData = getAssembler().getOrCreateSymbolData(*Symbol);
142 SymbolData.setExternal(External);
144 AssignSection(Symbol, Section);
146 if (ByteAlignment != 1)
147 new MCAlignFragment(ByteAlignment, 0, 0, ByteAlignment, &SectionData);
149 SymbolData.setFragment(new MCFillFragment(0, 0, Size, &SectionData));
152 // MCStreamer interface
154 void WinCOFFStreamer::InitToTextSection() {
158 void WinCOFFStreamer::InitSections() {
165 void WinCOFFStreamer::EmitLabel(MCSymbol *Symbol) {
166 assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
167 MCObjectStreamer::EmitLabel(Symbol);
170 void WinCOFFStreamer::EmitDebugLabel(MCSymbol *Symbol) {
173 void WinCOFFStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
174 llvm_unreachable("not implemented");
177 void WinCOFFStreamer::EmitThumbFunc(MCSymbol *Func) {
178 llvm_unreachable("not implemented");
181 bool WinCOFFStreamer::EmitSymbolAttribute(MCSymbol *Symbol,
182 MCSymbolAttr Attribute) {
183 assert(Symbol && "Symbol must be non-null!");
184 assert((Symbol->isInSection()
185 ? Symbol->getSection().getVariant() == MCSection::SV_COFF
186 : true) && "Got non-COFF section in the COFF backend!");
188 case MCSA_WeakReference:
190 MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
191 SD.modifyFlags(COFF::SF_WeakExternal, COFF::SF_WeakExternal);
192 SD.setExternal(true);
197 getAssembler().getOrCreateSymbolData(*Symbol).setExternal(true);
207 void WinCOFFStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
208 llvm_unreachable("not implemented");
211 void WinCOFFStreamer::BeginCOFFSymbolDef(MCSymbol const *Symbol) {
212 assert((Symbol->isInSection()
213 ? Symbol->getSection().getVariant() == MCSection::SV_COFF
214 : true) && "Got non-COFF section in the COFF backend!");
215 assert(CurSymbol == NULL && "EndCOFFSymbolDef must be called between calls "
216 "to BeginCOFFSymbolDef!");
220 void WinCOFFStreamer::EmitCOFFSymbolStorageClass(int StorageClass) {
221 assert(CurSymbol != NULL && "BeginCOFFSymbolDef must be called first!");
222 assert((StorageClass & ~0xFF) == 0 && "StorageClass must only have data in "
225 getAssembler().getOrCreateSymbolData(*CurSymbol).modifyFlags(
226 StorageClass << COFF::SF_ClassShift,
230 void WinCOFFStreamer::EmitCOFFSymbolType(int Type) {
231 assert(CurSymbol != NULL && "BeginCOFFSymbolDef must be called first!");
232 assert((Type & ~0xFFFF) == 0 && "Type must only have data in the first 2 "
235 getAssembler().getOrCreateSymbolData(*CurSymbol).modifyFlags(
236 Type << COFF::SF_TypeShift,
240 void WinCOFFStreamer::EndCOFFSymbolDef() {
241 assert(CurSymbol != NULL && "BeginCOFFSymbolDef must be called first!");
245 void WinCOFFStreamer::EmitCOFFSectionIndex(MCSymbol const *Symbol) {
246 MCDataFragment *DF = getOrCreateDataFragment();
247 DF->getFixups().push_back(MCFixup::Create(
248 DF->getContents().size(), MCSymbolRefExpr::Create(Symbol, getContext()),
250 DF->getContents().resize(DF->getContents().size() + 4, 0);
253 void WinCOFFStreamer::EmitCOFFSecRel32(MCSymbol const *Symbol) {
254 MCDataFragment *DF = getOrCreateDataFragment();
255 DF->getFixups().push_back(MCFixup::Create(
256 DF->getContents().size(), MCSymbolRefExpr::Create(Symbol, getContext()),
258 DF->getContents().resize(DF->getContents().size() + 4, 0);
261 void WinCOFFStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
262 llvm_unreachable("not implemented");
265 void WinCOFFStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
266 unsigned ByteAlignment) {
267 assert((Symbol->isInSection()
268 ? Symbol->getSection().getVariant() == MCSection::SV_COFF
269 : true) && "Got non-COFF section in the COFF backend!");
270 AddCommonSymbol(Symbol, Size, ByteAlignment, true);
273 void WinCOFFStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
274 unsigned ByteAlignment) {
275 assert((Symbol->isInSection()
276 ? Symbol->getSection().getVariant() == MCSection::SV_COFF
277 : true) && "Got non-COFF section in the COFF backend!");
278 AddCommonSymbol(Symbol, Size, ByteAlignment, false);
281 void WinCOFFStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
282 uint64_t Size,unsigned ByteAlignment) {
283 llvm_unreachable("not implemented");
286 void WinCOFFStreamer::EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
287 uint64_t Size, unsigned ByteAlignment) {
288 llvm_unreachable("not implemented");
291 void WinCOFFStreamer::EmitFileDirective(StringRef Filename) {
292 // Ignore for now, linkers don't care, and proper debug
293 // info will be a much large effort.
296 // TODO: Implement this if you want to emit .comment section in COFF obj files.
297 void WinCOFFStreamer::EmitIdent(StringRef IdentString) {
298 llvm_unreachable("unsupported directive");
301 void WinCOFFStreamer::EmitWin64EHHandlerData() {
302 MCStreamer::EmitWin64EHHandlerData();
304 // We have to emit the unwind info now, because this directive
305 // actually switches to the .xdata section!
306 MCWin64EHUnwindEmitter::EmitUnwindInfo(*this, getCurrentW64UnwindInfo());
309 void WinCOFFStreamer::FinishImpl() {
310 EmitFrames(NULL, true);
312 MCObjectStreamer::FinishImpl();
317 MCStreamer *createWinCOFFStreamer(MCContext &Context,
322 WinCOFFStreamer *S = new WinCOFFStreamer(Context, MAB, CE, OS);
323 S->getAssembler().setRelaxAll(RelaxAll);