MCStreamer.cpp revision f9efd83166401bca542c6702ea329f9901c4e04b
1//===- lib/MC/MCStreamer.cpp - Streaming Machine Code Output --------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9 10#include "llvm/MC/MCAsmInfo.h" 11#include "llvm/MC/MCContext.h" 12#include "llvm/MC/MCStreamer.h" 13#include "llvm/MC/MCExpr.h" 14#include "llvm/MC/MCObjectWriter.h" 15#include "llvm/MC/MCSymbol.h" 16#include "llvm/Support/ErrorHandling.h" 17#include "llvm/Support/raw_ostream.h" 18#include "llvm/ADT/SmallString.h" 19#include "llvm/ADT/Twine.h" 20#include <cstdlib> 21using namespace llvm; 22 23MCStreamer::MCStreamer(MCContext &Ctx) : Context(Ctx), EmitEHFrame(true), 24 EmitDebugFrame(false) { 25 const MCSection *section = NULL; 26 SectionStack.push_back(std::make_pair(section, section)); 27} 28 29MCStreamer::~MCStreamer() { 30} 31 32const MCExpr *MCStreamer::BuildSymbolDiff(MCContext &Context, 33 const MCSymbol *A, 34 const MCSymbol *B) { 35 MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None; 36 const MCExpr *ARef = 37 MCSymbolRefExpr::Create(A, Variant, Context); 38 const MCExpr *BRef = 39 MCSymbolRefExpr::Create(B, Variant, Context); 40 const MCExpr *AddrDelta = 41 MCBinaryExpr::Create(MCBinaryExpr::Sub, ARef, BRef, Context); 42 return AddrDelta; 43} 44 45const MCExpr *MCStreamer::ForceExpAbs(MCStreamer *Streamer, 46 MCContext &Context, const MCExpr* Expr) { 47 if (Context.getAsmInfo().hasAggressiveSymbolFolding()) 48 return Expr; 49 50 MCSymbol *ABS = Context.CreateTempSymbol(); 51 Streamer->EmitAssignment(ABS, Expr); 52 return MCSymbolRefExpr::Create(ABS, Context); 53} 54 55raw_ostream &MCStreamer::GetCommentOS() { 56 // By default, discard comments. 57 return nulls(); 58} 59 60void MCStreamer::EmitDwarfSetLineAddr(int64_t LineDelta, 61 const MCSymbol *Label, int PointerSize) { 62 // emit the sequence to set the address 63 EmitIntValue(dwarf::DW_LNS_extended_op, 1); 64 EmitULEB128IntValue(PointerSize + 1); 65 EmitIntValue(dwarf::DW_LNE_set_address, 1); 66 EmitSymbolValue(Label, PointerSize); 67 68 // emit the sequence for the LineDelta (from 1) and a zero address delta. 69 MCDwarfLineAddr::Emit(this, LineDelta, 0); 70} 71 72/// EmitIntValue - Special case of EmitValue that avoids the client having to 73/// pass in a MCExpr for constant integers. 74void MCStreamer::EmitIntValue(uint64_t Value, unsigned Size, 75 unsigned AddrSpace) { 76 assert(Size <= 8 && "Invalid size"); 77 assert((isUIntN(8 * Size, Value) || isIntN(8 * Size, Value)) && 78 "Invalid size"); 79 char buf[8]; 80 // FIXME: Endianness assumption. 81 for (unsigned i = 0; i != Size; ++i) 82 buf[i] = uint8_t(Value >> (i * 8)); 83 EmitBytes(StringRef(buf, Size), AddrSpace); 84} 85 86/// EmitULEB128Value - Special case of EmitULEB128Value that avoids the 87/// client having to pass in a MCExpr for constant integers. 88void MCStreamer::EmitULEB128IntValue(uint64_t Value, unsigned AddrSpace) { 89 SmallString<32> Tmp; 90 raw_svector_ostream OSE(Tmp); 91 MCObjectWriter::EncodeULEB128(Value, OSE); 92 EmitBytes(OSE.str(), AddrSpace); 93} 94 95/// EmitSLEB128Value - Special case of EmitSLEB128Value that avoids the 96/// client having to pass in a MCExpr for constant integers. 97void MCStreamer::EmitSLEB128IntValue(int64_t Value, unsigned AddrSpace) { 98 SmallString<32> Tmp; 99 raw_svector_ostream OSE(Tmp); 100 MCObjectWriter::EncodeSLEB128(Value, OSE); 101 EmitBytes(OSE.str(), AddrSpace); 102} 103 104void MCStreamer::EmitAbsValue(const MCExpr *Value, unsigned Size, 105 unsigned AddrSpace) { 106 if (getContext().getAsmInfo().hasAggressiveSymbolFolding()) { 107 EmitValue(Value, Size, AddrSpace); 108 return; 109 } 110 MCSymbol *ABS = getContext().CreateTempSymbol(); 111 EmitAssignment(ABS, Value); 112 EmitSymbolValue(ABS, Size, AddrSpace); 113} 114 115 116void MCStreamer::EmitValue(const MCExpr *Value, unsigned Size, 117 unsigned AddrSpace) { 118 EmitValueImpl(Value, Size, AddrSpace); 119} 120 121void MCStreamer::EmitSymbolValue(const MCSymbol *Sym, unsigned Size, 122 unsigned AddrSpace) { 123 EmitValueImpl(MCSymbolRefExpr::Create(Sym, getContext()), Size, 124 AddrSpace); 125} 126 127void MCStreamer::EmitGPRel32Value(const MCExpr *Value) { 128 report_fatal_error("unsupported directive in streamer"); 129} 130 131/// EmitFill - Emit NumBytes bytes worth of the value specified by 132/// FillValue. This implements directives such as '.space'. 133void MCStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue, 134 unsigned AddrSpace) { 135 const MCExpr *E = MCConstantExpr::Create(FillValue, getContext()); 136 for (uint64_t i = 0, e = NumBytes; i != e; ++i) 137 EmitValue(E, 1, AddrSpace); 138} 139 140bool MCStreamer::EmitDwarfFileDirective(unsigned FileNo, 141 StringRef Filename) { 142 return getContext().GetDwarfFile(Filename, FileNo) == 0; 143} 144 145void MCStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line, 146 unsigned Column, unsigned Flags, 147 unsigned Isa, 148 unsigned Discriminator, 149 StringRef FileName) { 150 getContext().setCurrentDwarfLoc(FileNo, Line, Column, Flags, Isa, 151 Discriminator); 152} 153 154MCDwarfFrameInfo *MCStreamer::getCurrentFrameInfo() { 155 if (FrameInfos.empty()) 156 return NULL; 157 return &FrameInfos.back(); 158} 159 160void MCStreamer::EnsureValidFrame() { 161 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 162 if (!CurFrame || CurFrame->End) 163 report_fatal_error("No open frame"); 164} 165 166void MCStreamer::EmitEHSymAttributes(const MCSymbol *Symbol, 167 MCSymbol *EHSymbol) { 168} 169 170void MCStreamer::EmitLabel(MCSymbol *Symbol) { 171 assert(!Symbol->isVariable() && "Cannot emit a variable symbol!"); 172 assert(getCurrentSection() && "Cannot emit before setting section!"); 173 Symbol->setSection(*getCurrentSection()); 174 175 StringRef Prefix = getContext().getAsmInfo().getPrivateGlobalPrefix(); 176 if (!Symbol->getName().startswith(Prefix)) 177 LastNonPrivate = Symbol; 178} 179 180void MCStreamer::EmitCFISections(bool EH, bool Debug) { 181 EmitEHFrame = EH; 182 EmitDebugFrame = Debug; 183} 184 185void MCStreamer::EmitCFIStartProc() { 186 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 187 if (CurFrame && !CurFrame->End) 188 report_fatal_error("Starting a frame before finishing the previous one!"); 189 MCDwarfFrameInfo Frame; 190 Frame.Begin = getContext().CreateTempSymbol(); 191 Frame.Function = LastNonPrivate; 192 EmitLabel(Frame.Begin); 193 FrameInfos.push_back(Frame); 194} 195 196void MCStreamer::EmitCFIEndProc() { 197 EnsureValidFrame(); 198 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 199 CurFrame->End = getContext().CreateTempSymbol(); 200 EmitLabel(CurFrame->End); 201} 202 203void MCStreamer::EmitCFIDefCfa(int64_t Register, int64_t Offset) { 204 EnsureValidFrame(); 205 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 206 MCSymbol *Label = getContext().CreateTempSymbol(); 207 EmitLabel(Label); 208 MachineLocation Dest(MachineLocation::VirtualFP); 209 MachineLocation Source(Register, -Offset); 210 MCCFIInstruction Instruction(Label, Dest, Source); 211 CurFrame->Instructions.push_back(Instruction); 212} 213 214void MCStreamer::EmitCFIDefCfaOffset(int64_t Offset) { 215 EnsureValidFrame(); 216 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 217 MCSymbol *Label = getContext().CreateTempSymbol(); 218 EmitLabel(Label); 219 MachineLocation Dest(MachineLocation::VirtualFP); 220 MachineLocation Source(MachineLocation::VirtualFP, -Offset); 221 MCCFIInstruction Instruction(Label, Dest, Source); 222 CurFrame->Instructions.push_back(Instruction); 223} 224 225void MCStreamer::EmitCFIAdjustCfaOffset(int64_t Adjustment) { 226 EnsureValidFrame(); 227 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 228 MCSymbol *Label = getContext().CreateTempSymbol(); 229 EmitLabel(Label); 230 MachineLocation Dest(MachineLocation::VirtualFP); 231 MachineLocation Source(MachineLocation::VirtualFP, Adjustment); 232 MCCFIInstruction Instruction(MCCFIInstruction::RelMove, Label, Dest, Source); 233 CurFrame->Instructions.push_back(Instruction); 234} 235 236void MCStreamer::EmitCFIDefCfaRegister(int64_t Register) { 237 EnsureValidFrame(); 238 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 239 MCSymbol *Label = getContext().CreateTempSymbol(); 240 EmitLabel(Label); 241 MachineLocation Dest(Register); 242 MachineLocation Source(MachineLocation::VirtualFP); 243 MCCFIInstruction Instruction(Label, Dest, Source); 244 CurFrame->Instructions.push_back(Instruction); 245} 246 247void MCStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) { 248 EnsureValidFrame(); 249 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 250 MCSymbol *Label = getContext().CreateTempSymbol(); 251 EmitLabel(Label); 252 MachineLocation Dest(Register, Offset); 253 MachineLocation Source(Register, Offset); 254 MCCFIInstruction Instruction(Label, Dest, Source); 255 CurFrame->Instructions.push_back(Instruction); 256} 257 258void MCStreamer::EmitCFIRelOffset(int64_t Register, int64_t Offset) { 259 EnsureValidFrame(); 260 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 261 MCSymbol *Label = getContext().CreateTempSymbol(); 262 EmitLabel(Label); 263 MachineLocation Dest(Register, Offset); 264 MachineLocation Source(Register, Offset); 265 MCCFIInstruction Instruction(MCCFIInstruction::RelMove, Label, Dest, Source); 266 CurFrame->Instructions.push_back(Instruction); 267} 268 269void MCStreamer::EmitCFIPersonality(const MCSymbol *Sym, 270 unsigned Encoding) { 271 EnsureValidFrame(); 272 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 273 CurFrame->Personality = Sym; 274 CurFrame->PersonalityEncoding = Encoding; 275} 276 277void MCStreamer::EmitCFILsda(const MCSymbol *Sym, unsigned Encoding) { 278 EnsureValidFrame(); 279 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 280 CurFrame->Lsda = Sym; 281 CurFrame->LsdaEncoding = Encoding; 282} 283 284void MCStreamer::EmitCFIRememberState() { 285 EnsureValidFrame(); 286 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 287 MCSymbol *Label = getContext().CreateTempSymbol(); 288 EmitLabel(Label); 289 MCCFIInstruction Instruction(MCCFIInstruction::Remember, Label); 290 CurFrame->Instructions.push_back(Instruction); 291} 292 293void MCStreamer::EmitCFIRestoreState() { 294 // FIXME: Error if there is no matching cfi_remember_state. 295 EnsureValidFrame(); 296 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 297 MCSymbol *Label = getContext().CreateTempSymbol(); 298 EmitLabel(Label); 299 MCCFIInstruction Instruction(MCCFIInstruction::Restore, Label); 300 CurFrame->Instructions.push_back(Instruction); 301} 302 303void MCStreamer::EmitCFISameValue(int64_t Register) { 304 EnsureValidFrame(); 305 MCDwarfFrameInfo *CurFrame = getCurrentFrameInfo(); 306 MCSymbol *Label = getContext().CreateTempSymbol(); 307 EmitLabel(Label); 308 MCCFIInstruction Instruction(MCCFIInstruction::SameValue, Label, Register); 309 CurFrame->Instructions.push_back(Instruction); 310} 311 312void MCStreamer::EmitFnStart() { 313 errs() << "Not implemented yet\n"; 314 abort(); 315} 316 317void MCStreamer::EmitFnEnd() { 318 errs() << "Not implemented yet\n"; 319 abort(); 320} 321 322void MCStreamer::EmitCantUnwind() { 323 errs() << "Not implemented yet\n"; 324 abort(); 325} 326 327void MCStreamer::EmitHandlerData() { 328 errs() << "Not implemented yet\n"; 329 abort(); 330} 331 332void MCStreamer::EmitPersonality(const MCSymbol *Personality) { 333 errs() << "Not implemented yet\n"; 334 abort(); 335} 336 337void MCStreamer::EmitSetFP(unsigned FpReg, unsigned SpReg, int64_t Offset) { 338 errs() << "Not implemented yet\n"; 339 abort(); 340} 341 342void MCStreamer::EmitPad(int64_t Offset) { 343 errs() << "Not implemented yet\n"; 344 abort(); 345} 346 347void MCStreamer::EmitRegSave(const SmallVectorImpl<unsigned> &RegList, bool) { 348 errs() << "Not implemented yet\n"; 349 abort(); 350} 351 352/// EmitRawText - If this file is backed by an assembly streamer, this dumps 353/// the specified string in the output .s file. This capability is 354/// indicated by the hasRawTextSupport() predicate. 355void MCStreamer::EmitRawText(StringRef String) { 356 errs() << "EmitRawText called on an MCStreamer that doesn't support it, " 357 " something must not be fully mc'ized\n"; 358 abort(); 359} 360 361void MCStreamer::EmitRawText(const Twine &T) { 362 SmallString<128> Str; 363 T.toVector(Str); 364 EmitRawText(Str.str()); 365} 366