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/MCObjectStreamer.h"
24 #include "llvm/MC/MCSection.h"
25 #include "llvm/MC/MCSectionCOFF.h"
26 #include "llvm/MC/MCSymbol.h"
27 #include "llvm/MC/MCValue.h"
28 #include "llvm/MC/MCWin64EH.h"
29 #include "llvm/Support/COFF.h"
30 #include "llvm/Support/Debug.h"
31 #include "llvm/Support/ErrorHandling.h"
32 #include "llvm/Support/TargetRegistry.h"
33 #include "llvm/Support/raw_ostream.h"
38 class WinCOFFStreamer : public MCObjectStreamer {
40 MCSymbol const *CurSymbol;
42 WinCOFFStreamer(MCContext &Context,
47 void AddCommonSymbol(MCSymbol *Symbol, uint64_t Size,
48 unsigned ByteAlignment, bool External);
50 // MCStreamer interface
52 virtual void InitSections();
53 virtual void InitToTextSection();
54 virtual void EmitLabel(MCSymbol *Symbol);
55 virtual void EmitDebugLabel(MCSymbol *Symbol);
56 virtual void EmitAssemblerFlag(MCAssemblerFlag Flag);
57 virtual void EmitThumbFunc(MCSymbol *Func);
58 virtual bool EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute);
59 virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
60 virtual void BeginCOFFSymbolDef(MCSymbol const *Symbol);
61 virtual void EmitCOFFSymbolStorageClass(int StorageClass);
62 virtual void EmitCOFFSymbolType(int Type);
63 virtual void EndCOFFSymbolDef();
64 virtual void EmitCOFFSectionIndex(MCSymbol const *Symbol);
65 virtual void EmitCOFFSecRel32(MCSymbol const *Symbol);
66 virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value);
67 virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
68 unsigned ByteAlignment);
69 virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
70 unsigned ByteAlignment);
71 virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
72 uint64_t Size,unsigned ByteAlignment);
73 virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
74 uint64_t Size, unsigned ByteAlignment);
75 virtual void EmitFileDirective(StringRef Filename);
76 virtual void EmitIdent(StringRef IdentString);
77 virtual void EmitWin64EHHandlerData();
78 virtual void FinishImpl();
81 virtual void EmitInstToData(const MCInst &Inst) {
82 MCDataFragment *DF = getOrCreateDataFragment();
84 SmallVector<MCFixup, 4> Fixups;
85 SmallString<256> Code;
86 raw_svector_ostream VecOS(Code);
87 getAssembler().getEmitter().EncodeInstruction(Inst, VecOS, Fixups);
90 // Add the fixups and data.
91 for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
92 Fixups[i].setOffset(Fixups[i].getOffset() + DF->getContents().size());
93 DF->getFixups().push_back(Fixups[i]);
95 DF->getContents().append(Code.begin(), Code.end());
98 const MCSectionCOFF *getSectionText() {
99 return getContext().getCOFFSection(
100 ".text", COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE |
101 COFF::IMAGE_SCN_MEM_READ,
102 SectionKind::getText());
105 const MCSectionCOFF *getSectionData() {
106 return getContext().getCOFFSection(
107 ".data", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
108 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE,
109 SectionKind::getDataRel());
112 const MCSectionCOFF *getSectionBSS() {
113 return getContext().getCOFFSection(
114 ".bss", COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
115 COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE,
116 SectionKind::getBSS());
119 void SetSectionText() {
120 SwitchSection(getSectionText());
121 EmitCodeAlignment(4, 0);
124 void SetSectionData() {
125 SwitchSection(getSectionData());
126 EmitCodeAlignment(4, 0);
129 void SetSectionBSS() {
130 SwitchSection(getSectionBSS());
131 EmitCodeAlignment(4, 0);
134 } // end anonymous namespace.
136 WinCOFFStreamer::WinCOFFStreamer(MCContext &Context, MCAsmBackend &MAB,
137 MCCodeEmitter &CE, raw_ostream &OS)
138 : MCObjectStreamer(Context, 0, MAB, OS, &CE), CurSymbol(NULL) {}
140 void WinCOFFStreamer::AddCommonSymbol(MCSymbol *Symbol, uint64_t Size,
141 unsigned ByteAlignment, bool External) {
142 assert(!Symbol->isInSection() && "Symbol must not already have a section!");
144 const MCSectionCOFF *Section = getSectionBSS();
145 MCSectionData &SectionData = getAssembler().getOrCreateSectionData(*Section);
146 if (SectionData.getAlignment() < ByteAlignment)
147 SectionData.setAlignment(ByteAlignment);
149 MCSymbolData &SymbolData = getAssembler().getOrCreateSymbolData(*Symbol);
150 SymbolData.setExternal(External);
152 AssignSection(Symbol, Section);
154 if (ByteAlignment != 1)
155 new MCAlignFragment(ByteAlignment, 0, 0, ByteAlignment, &SectionData);
157 SymbolData.setFragment(new MCFillFragment(0, 0, Size, &SectionData));
160 // MCStreamer interface
162 void WinCOFFStreamer::InitToTextSection() {
166 void WinCOFFStreamer::InitSections() {
173 void WinCOFFStreamer::EmitLabel(MCSymbol *Symbol) {
174 assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
175 MCObjectStreamer::EmitLabel(Symbol);
178 void WinCOFFStreamer::EmitDebugLabel(MCSymbol *Symbol) {
181 void WinCOFFStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
182 llvm_unreachable("not implemented");
185 void WinCOFFStreamer::EmitThumbFunc(MCSymbol *Func) {
186 llvm_unreachable("not implemented");
189 bool WinCOFFStreamer::EmitSymbolAttribute(MCSymbol *Symbol,
190 MCSymbolAttr Attribute) {
191 assert(Symbol && "Symbol must be non-null!");
192 assert((Symbol->isInSection()
193 ? Symbol->getSection().getVariant() == MCSection::SV_COFF
194 : true) && "Got non-COFF section in the COFF backend!");
196 case MCSA_WeakReference:
198 MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
199 SD.modifyFlags(COFF::SF_WeakExternal, COFF::SF_WeakExternal);
200 SD.setExternal(true);
205 getAssembler().getOrCreateSymbolData(*Symbol).setExternal(true);
215 void WinCOFFStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
216 llvm_unreachable("not implemented");
219 void WinCOFFStreamer::BeginCOFFSymbolDef(MCSymbol const *Symbol) {
220 assert((Symbol->isInSection()
221 ? Symbol->getSection().getVariant() == MCSection::SV_COFF
222 : true) && "Got non-COFF section in the COFF backend!");
223 assert(CurSymbol == NULL && "EndCOFFSymbolDef must be called between calls "
224 "to BeginCOFFSymbolDef!");
228 void WinCOFFStreamer::EmitCOFFSymbolStorageClass(int StorageClass) {
229 assert(CurSymbol != NULL && "BeginCOFFSymbolDef must be called first!");
230 assert((StorageClass & ~0xFF) == 0 && "StorageClass must only have data in "
233 getAssembler().getOrCreateSymbolData(*CurSymbol).modifyFlags(
234 StorageClass << COFF::SF_ClassShift,
238 void WinCOFFStreamer::EmitCOFFSymbolType(int Type) {
239 assert(CurSymbol != NULL && "BeginCOFFSymbolDef must be called first!");
240 assert((Type & ~0xFFFF) == 0 && "Type must only have data in the first 2 "
243 getAssembler().getOrCreateSymbolData(*CurSymbol).modifyFlags(
244 Type << COFF::SF_TypeShift,
248 void WinCOFFStreamer::EndCOFFSymbolDef() {
249 assert(CurSymbol != NULL && "BeginCOFFSymbolDef must be called first!");
253 void WinCOFFStreamer::EmitCOFFSectionIndex(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::EmitCOFFSecRel32(MCSymbol const *Symbol) {
262 MCDataFragment *DF = getOrCreateDataFragment();
263 DF->getFixups().push_back(MCFixup::Create(
264 DF->getContents().size(), MCSymbolRefExpr::Create(Symbol, getContext()),
266 DF->getContents().resize(DF->getContents().size() + 4, 0);
269 void WinCOFFStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
270 llvm_unreachable("not implemented");
273 void WinCOFFStreamer::EmitCommonSymbol(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, true);
281 void WinCOFFStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
282 unsigned ByteAlignment) {
283 assert((Symbol->isInSection()
284 ? Symbol->getSection().getVariant() == MCSection::SV_COFF
285 : true) && "Got non-COFF section in the COFF backend!");
286 AddCommonSymbol(Symbol, Size, ByteAlignment, false);
289 void WinCOFFStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
290 uint64_t Size,unsigned ByteAlignment) {
291 llvm_unreachable("not implemented");
294 void WinCOFFStreamer::EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
295 uint64_t Size, unsigned ByteAlignment) {
296 llvm_unreachable("not implemented");
299 void WinCOFFStreamer::EmitFileDirective(StringRef Filename) {
300 // Ignore for now, linkers don't care, and proper debug
301 // info will be a much large effort.
304 // TODO: Implement this if you want to emit .comment section in COFF obj files.
305 void WinCOFFStreamer::EmitIdent(StringRef IdentString) {
306 llvm_unreachable("unsupported directive");
309 void WinCOFFStreamer::EmitWin64EHHandlerData() {
310 MCStreamer::EmitWin64EHHandlerData();
312 // We have to emit the unwind info now, because this directive
313 // actually switches to the .xdata section!
314 MCWin64EHUnwindEmitter::EmitUnwindInfo(*this, getCurrentW64UnwindInfo());
317 void WinCOFFStreamer::FinishImpl() {
318 EmitFrames(NULL, true);
320 MCObjectStreamer::FinishImpl();
325 MCStreamer *createWinCOFFStreamer(MCContext &Context,
330 WinCOFFStreamer *S = new WinCOFFStreamer(Context, MAB, CE, OS);
331 S->getAssembler().setRelaxAll(RelaxAll);