1 //===- lib/MC/MCAsmStreamer.cpp - Text Assembly Output --------------------===//
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 #include "llvm/MC/MCStreamer.h"
11 #include "llvm/CodeGen/AsmPrinter.h"
12 #include "llvm/MC/MCContext.h"
13 #include "llvm/MC/MCInst.h"
14 #include "llvm/MC/MCSectionMachO.h"
15 #include "llvm/MC/MCSymbol.h"
16 #include "llvm/MC/MCValue.h"
17 #include "llvm/Support/ErrorHandling.h"
18 #include "llvm/Support/raw_ostream.h"
23 class MCAsmStreamer : public MCStreamer {
25 const TargetAsmInfo &TAI;
28 MCAsmStreamer(MCContext &Context, raw_ostream &_OS, const TargetAsmInfo &tai,
29 AsmPrinter *_AsmPrinter)
30 : MCStreamer(Context), OS(_OS), TAI(tai), Printer(_AsmPrinter) {}
33 /// @name MCStreamer Interface
36 virtual void SwitchSection(const MCSection *Section);
38 virtual void EmitLabel(MCSymbol *Symbol);
40 virtual void EmitAssemblerFlag(AssemblerFlag Flag);
42 virtual void EmitAssignment(MCSymbol *Symbol, const MCValue &Value,
43 bool MakeAbsolute = false);
45 virtual void EmitSymbolAttribute(MCSymbol *Symbol, SymbolAttr Attribute);
47 virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue);
49 virtual void EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value);
51 virtual void EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
52 unsigned Pow2Alignment, bool IsLocal);
54 virtual void EmitZerofill(MCSection *Section, MCSymbol *Symbol = NULL,
55 unsigned Size = 0, unsigned Pow2Alignment = 0);
57 virtual void EmitBytes(const StringRef &Data);
59 virtual void EmitValue(const MCValue &Value, unsigned Size);
61 virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
62 unsigned ValueSize = 1,
63 unsigned MaxBytesToEmit = 0);
65 virtual void EmitValueToOffset(const MCValue &Offset,
66 unsigned char Value = 0);
68 virtual void EmitInstruction(const MCInst &Inst);
70 virtual void Finish();
75 } // end anonymous namespace.
77 /// Allow printing symbols directly to a raw_ostream with proper quoting.
78 static inline raw_ostream &operator<<(raw_ostream &os, const MCSymbol *S) {
83 /// Allow printing values directly to a raw_ostream.
84 static inline raw_ostream &operator<<(raw_ostream &os, const MCValue &Value) {
89 static inline int64_t truncateToSize(int64_t Value, unsigned Bytes) {
90 assert(Bytes && "Invalid size!");
91 return Value & ((uint64_t) (int64_t) -1 >> (64 - Bytes * 8));
94 static inline MCValue truncateToSize(const MCValue &Value, unsigned Bytes) {
95 return MCValue::get(Value.getSymA(), Value.getSymB(),
96 truncateToSize(Value.getConstant(), Bytes));
99 void MCAsmStreamer::SwitchSection(const MCSection *Section) {
100 assert(Section && "Cannot switch to a null section!");
101 if (Section != CurSection) {
102 CurSection = Section;
103 Section->PrintSwitchToSection(TAI, OS);
107 void MCAsmStreamer::EmitLabel(MCSymbol *Symbol) {
108 assert(Symbol->getSection() == 0 && "Cannot emit a symbol twice!");
109 assert(CurSection && "Cannot emit before setting section!");
110 assert(!getContext().GetSymbolValue(Symbol) &&
111 "Cannot emit symbol which was directly assigned to!");
113 OS << Symbol << ":\n";
114 Symbol->setSection(CurSection);
115 Symbol->setExternal(false);
118 void MCAsmStreamer::EmitAssemblerFlag(AssemblerFlag Flag) {
120 default: assert(0 && "Invalid flag!");
121 case SubsectionsViaSymbols: OS << ".subsections_via_symbols"; break;
126 void MCAsmStreamer::EmitAssignment(MCSymbol *Symbol, const MCValue &Value,
128 assert(!Symbol->getSection() && "Cannot assign to a label!");
131 OS << ".set " << Symbol << ", " << Value << '\n';
133 // HACK: If the value isn't already absolute, set the symbol value to
134 // itself, we want to use the .set absolute value, not the actual
136 if (!Value.isAbsolute())
137 getContext().SetSymbolValue(Symbol, MCValue::get(Symbol));
139 getContext().SetSymbolValue(Symbol, Value);
141 OS << Symbol << " = " << Value << '\n';
142 getContext().SetSymbolValue(Symbol, Value);
146 void MCAsmStreamer::EmitSymbolAttribute(MCSymbol *Symbol,
147 SymbolAttr Attribute) {
149 case Global: OS << ".globl"; break;
150 case Hidden: OS << ".hidden"; break;
151 case IndirectSymbol: OS << ".indirect_symbol"; break;
152 case Internal: OS << ".internal"; break;
153 case LazyReference: OS << ".lazy_reference"; break;
154 case NoDeadStrip: OS << ".no_dead_strip"; break;
155 case PrivateExtern: OS << ".private_extern"; break;
156 case Protected: OS << ".protected"; break;
157 case Reference: OS << ".reference"; break;
158 case Weak: OS << ".weak"; break;
159 case WeakDefinition: OS << ".weak_definition"; break;
160 case WeakReference: OS << ".weak_reference"; break;
163 OS << ' ' << Symbol << '\n';
166 void MCAsmStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
167 OS << ".desc" << ' ' << Symbol << ',' << DescValue << '\n';
170 void MCAsmStreamer::EmitLocalSymbol(MCSymbol *Symbol, const MCValue &Value) {
171 OS << ".lsym" << ' ' << Symbol << ',' << Value << '\n';
174 void MCAsmStreamer::EmitCommonSymbol(MCSymbol *Symbol, unsigned Size,
175 unsigned Pow2Alignment, bool IsLocal) {
180 OS << ' ' << Symbol << ',' << Size;
181 if (Pow2Alignment != 0)
182 OS << ',' << Pow2Alignment;
186 void MCAsmStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
187 unsigned Size, unsigned Pow2Alignment) {
188 // Note: a .zerofill directive does not switch sections.
191 // This is a mach-o specific directive.
192 const MCSectionMachO *MOSection = ((const MCSectionMachO*)Section);
193 OS << MOSection->getSegmentName() << "," << MOSection->getSectionName();
195 if (Symbol != NULL) {
196 OS << ',' << Symbol << ',' << Size;
197 if (Pow2Alignment != 0)
198 OS << ',' << Pow2Alignment;
203 void MCAsmStreamer::EmitBytes(const StringRef &Data) {
204 assert(CurSection && "Cannot emit contents before setting section!");
205 for (unsigned i = 0, e = Data.size(); i != e; ++i)
206 OS << ".byte " << (unsigned) (unsigned char) Data[i] << '\n';
209 void MCAsmStreamer::EmitValue(const MCValue &Value, unsigned Size) {
210 assert(CurSection && "Cannot emit contents before setting section!");
211 // Need target hooks to know how to print this.
214 llvm_unreachable("Invalid size for machine code value!");
215 case 1: OS << ".byte"; break;
216 case 2: OS << ".short"; break;
217 case 4: OS << ".long"; break;
218 case 8: OS << ".quad"; break;
221 OS << ' ' << truncateToSize(Value, Size) << '\n';
224 void MCAsmStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
226 unsigned MaxBytesToEmit) {
227 // Some assemblers don't support .balign, so we always emit as .p2align if
228 // this is a power of two. Otherwise we assume the client knows the target
229 // supports .balign and use that.
230 unsigned Pow2 = Log2_32(ByteAlignment);
231 bool IsPow2 = (1U << Pow2) == ByteAlignment;
235 llvm_unreachable("Invalid size for machine code value!");
237 llvm_unreachable("Unsupported alignment size!");
238 case 1: OS << (IsPow2 ? ".p2align" : ".balign"); break;
239 case 2: OS << (IsPow2 ? ".p2alignw" : ".balignw"); break;
240 case 4: OS << (IsPow2 ? ".p2alignl" : ".balignl"); break;
243 OS << ' ' << (IsPow2 ? Pow2 : ByteAlignment);
245 OS << ", " << truncateToSize(Value, ValueSize);
247 OS << ", " << MaxBytesToEmit;
251 void MCAsmStreamer::EmitValueToOffset(const MCValue &Offset,
252 unsigned char Value) {
253 // FIXME: Verify that Offset is associated with the current section.
254 OS << ".org " << Offset << ", " << (unsigned) Value << '\n';
257 static raw_ostream &operator<<(raw_ostream &OS, const MCOperand &Op) {
259 return OS << "reg:" << Op.getReg();
261 return OS << "imm:" << Op.getImm();
263 return OS << "mbblabel:("
264 << Op.getMBBLabelFunction() << ", " << Op.getMBBLabelBlock();
265 assert(Op.isMCValue() && "Invalid operand!");
266 return OS << "val:" << Op.getMCValue();
269 void MCAsmStreamer::EmitInstruction(const MCInst &Inst) {
270 assert(CurSection && "Cannot emit contents before setting section!");
272 // If we have an AsmPrinter, use that to print.
274 Printer->printMCInst(&Inst);
278 // Otherwise fall back to a structural printing for now. Eventually we should
279 // always have access to the target specific printer.
281 << "opcode=" << Inst.getOpcode() << ", "
283 for (unsigned i = 0, e = Inst.getNumOperands(); i != e; ++i) {
286 OS << Inst.getOperand(i);
291 void MCAsmStreamer::Finish() {
295 MCStreamer *llvm::createAsmStreamer(MCContext &Context, raw_ostream &OS,
296 const TargetAsmInfo &TAI, AsmPrinter *AP) {
297 return new MCAsmStreamer(Context, OS, TAI, AP);