MCStreamer.h revision af6b5808756d6ce335df9eb158efa33894b401c4
1116680a4aac90f2aa7413d9095a592090648e557Ben Murdoch//===- MCStreamer.h - High-level Streaming Machine Code Output --*- C++ -*-===// 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// The LLVM Compiler Infrastructure 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 5116680a4aac90f2aa7413d9095a592090648e557Ben Murdoch// This file is distributed under the University of Illinois Open Source 6116680a4aac90f2aa7413d9095a592090648e557Ben Murdoch// License. See LICENSE.TXT for details. 75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)//===----------------------------------------------------------------------===// 95f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)// 10116680a4aac90f2aa7413d9095a592090648e557Ben Murdoch// This file declares the MCStreamer class. 115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)//===----------------------------------------------------------------------===// 135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#ifndef LLVM_MC_MCSTREAMER_H 155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#define LLVM_MC_MCSTREAMER_H 165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "llvm/System/DataTypes.h" 185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "llvm/MC/MCDirectives.h" 195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 20116680a4aac90f2aa7413d9095a592090648e557Ben Murdochnamespace llvm { 21 class MCAsmInfo; 22 class MCCodeEmitter; 23 class MCContext; 24 class MCExpr; 25 class MCInst; 26 class MCInstPrinter; 27 class MCSection; 28 class MCSymbol; 29 class StringRef; 30 class TargetAsmBackend; 31 class Twine; 32 class raw_ostream; 33 class formatted_raw_ostream; 34 35 /// MCStreamer - Streaming machine code generation interface. This interface 36 /// is intended to provide a programatic interface that is very similar to the 37 /// level that an assembler .s file provides. It has callbacks to emit bytes, 38 /// handle directives, etc. The implementation of this interface retains 39 /// state to know what the current section is etc. 40 /// 41 /// There are multiple implementations of this interface: one for writing out 42 /// a .s file, and implementations that write out .o files of various formats. 43 /// 44 class MCStreamer { 45 MCContext &Context; 46 47 MCStreamer(const MCStreamer&); // DO NOT IMPLEMENT 48 MCStreamer &operator=(const MCStreamer&); // DO NOT IMPLEMENT 49 50 protected: 51 MCStreamer(MCContext &Ctx); 52 53 /// CurSection - This is the current section code is being emitted to, it is 54 /// kept up to date by SwitchSection. 55 const MCSection *CurSection; 56 57 /// PrevSection - This is the previous section code is being emitted to, it 58 /// is kept up to date by SwitchSection. 59 const MCSection *PrevSection; 60 61 public: 62 virtual ~MCStreamer(); 63 64 MCContext &getContext() const { return Context; } 65 66 /// @name Assembly File Formatting. 67 /// @{ 68 69 /// isVerboseAsm - Return true if this streamer supports verbose assembly 70 /// and if it is enabled. 71 virtual bool isVerboseAsm() const { return false; } 72 73 /// hasRawTextSupport - Return true if this asm streamer supports emitting 74 /// unformatted text to the .s file with EmitRawText. 75 virtual bool hasRawTextSupport() const { return false; } 76 77 /// AddComment - Add a comment that can be emitted to the generated .s 78 /// file if applicable as a QoI issue to make the output of the compiler 79 /// more readable. This only affects the MCAsmStreamer, and only when 80 /// verbose assembly output is enabled. 81 /// 82 /// If the comment includes embedded \n's, they will each get the comment 83 /// prefix as appropriate. The added comment should not end with a \n. 84 virtual void AddComment(const Twine &T) {} 85 86 /// GetCommentOS - Return a raw_ostream that comments can be written to. 87 /// Unlike AddComment, you are required to terminate comments with \n if you 88 /// use this method. 89 virtual raw_ostream &GetCommentOS(); 90 91 /// AddBlankLine - Emit a blank line to a .s file to pretty it up. 92 virtual void AddBlankLine() {} 93 94 /// @} 95 96 /// @name Symbol & Section Management 97 /// @{ 98 99 /// getCurrentSection - Return the current section that the streamer is 100 /// emitting code to. 101 const MCSection *getCurrentSection() const { return CurSection; } 102 103 /// getPreviousSection - Return the previous section that the streamer is 104 /// emitting code to. 105 const MCSection *getPreviousSection() const { return PrevSection; } 106 107 /// SwitchSection - Set the current section where code is being emitted to 108 /// @p Section. This is required to update CurSection. 109 /// 110 /// This corresponds to assembler directives like .section, .text, etc. 111 virtual void SwitchSection(const MCSection *Section) = 0; 112 113 /// InitSections - Create the default sections and set the initial one. 114 virtual void InitSections() = 0; 115 116 /// EmitLabel - Emit a label for @p Symbol into the current section. 117 /// 118 /// This corresponds to an assembler statement such as: 119 /// foo: 120 /// 121 /// @param Symbol - The symbol to emit. A given symbol should only be 122 /// emitted as a label once, and symbols emitted as a label should never be 123 /// used in an assignment. 124 virtual void EmitLabel(MCSymbol *Symbol) = 0; 125 126 /// EmitAssemblerFlag - Note in the output the specified @p Flag 127 virtual void EmitAssemblerFlag(MCAssemblerFlag Flag) = 0; 128 129 /// EmitThumbFunc - Note in the output that the specified @p Func is 130 /// a Thumb mode function (ARM target only). 131 virtual void EmitThumbFunc(MCSymbol *Func) = 0; 132 133 /// EmitAssignment - Emit an assignment of @p Value to @p Symbol. 134 /// 135 /// This corresponds to an assembler statement such as: 136 /// symbol = value 137 /// 138 /// The assignment generates no code, but has the side effect of binding the 139 /// value in the current context. For the assembly streamer, this prints the 140 /// binding into the .s file. 141 /// 142 /// @param Symbol - The symbol being assigned to. 143 /// @param Value - The value for the symbol. 144 virtual void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) = 0; 145 146 /// EmitWeakReference - Emit an weak reference from @p Alias to @p Symbol. 147 /// 148 /// This corresponds to an assembler statement such as: 149 /// .weakref alias, symbol 150 /// 151 /// @param Alias - The alias that is being created. 152 /// @param Symbol - The symbol being aliased. 153 virtual void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) = 0; 154 155 /// EmitSymbolAttribute - Add the given @p Attribute to @p Symbol. 156 virtual void EmitSymbolAttribute(MCSymbol *Symbol, 157 MCSymbolAttr Attribute) = 0; 158 159 /// EmitSymbolDesc - Set the @p DescValue for the @p Symbol. 160 /// 161 /// @param Symbol - The symbol to have its n_desc field set. 162 /// @param DescValue - The value to set into the n_desc field. 163 virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) = 0; 164 165 /// BeginCOFFSymbolDef - Start emitting COFF symbol definition 166 /// 167 /// @param Symbol - The symbol to have its External & Type fields set. 168 virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol) = 0; 169 170 /// EmitCOFFSymbolStorageClass - Emit the storage class of the symbol. 171 /// 172 /// @param StorageClass - The storage class the symbol should have. 173 virtual void EmitCOFFSymbolStorageClass(int StorageClass) = 0; 174 175 /// EmitCOFFSymbolType - Emit the type of the symbol. 176 /// 177 /// @param Type - A COFF type identifier (see COFF::SymbolType in X86COFF.h) 178 virtual void EmitCOFFSymbolType(int Type) = 0; 179 180 /// EndCOFFSymbolDef - Marks the end of the symbol definition. 181 virtual void EndCOFFSymbolDef() = 0; 182 183 /// EmitELFSize - Emit an ELF .size directive. 184 /// 185 /// This corresponds to an assembler statement such as: 186 /// .size symbol, expression 187 /// 188 virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) = 0; 189 190 /// EmitCommonSymbol - Emit a common symbol. 191 /// 192 /// @param Symbol - The common symbol to emit. 193 /// @param Size - The size of the common symbol. 194 /// @param ByteAlignment - The alignment of the symbol if 195 /// non-zero. This must be a power of 2. 196 virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size, 197 unsigned ByteAlignment) = 0; 198 199 /// EmitLocalCommonSymbol - Emit a local common (.lcomm) symbol. 200 /// 201 /// @param Symbol - The common symbol to emit. 202 /// @param Size - The size of the common symbol. 203 virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size) = 0; 204 205 /// EmitZerofill - Emit the zerofill section and an optional symbol. 206 /// 207 /// @param Section - The zerofill section to create and or to put the symbol 208 /// @param Symbol - The zerofill symbol to emit, if non-NULL. 209 /// @param Size - The size of the zerofill symbol. 210 /// @param ByteAlignment - The alignment of the zerofill symbol if 211 /// non-zero. This must be a power of 2 on some targets. 212 virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0, 213 unsigned Size = 0,unsigned ByteAlignment = 0) = 0; 214 215 /// EmitTBSSSymbol - Emit a thread local bss (.tbss) symbol. 216 /// 217 /// @param Section - The thread local common section. 218 /// @param Symbol - The thread local common symbol to emit. 219 /// @param Size - The size of the symbol. 220 /// @param ByteAlignment - The alignment of the thread local common symbol 221 /// if non-zero. This must be a power of 2 on some targets. 222 virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol, 223 uint64_t Size, unsigned ByteAlignment = 0) = 0; 224 /// @} 225 /// @name Generating Data 226 /// @{ 227 228 /// EmitBytes - Emit the bytes in \arg Data into the output. 229 /// 230 /// This is used to implement assembler directives such as .byte, .ascii, 231 /// etc. 232 virtual void EmitBytes(StringRef Data, unsigned AddrSpace) = 0; 233 234 /// EmitValue - Emit the expression @p Value into the output as a native 235 /// integer of the given @p Size bytes. 236 /// 237 /// This is used to implement assembler directives such as .word, .quad, 238 /// etc. 239 /// 240 /// @param Value - The value to emit. 241 /// @param Size - The size of the integer (in bytes) to emit. This must 242 /// match a native machine width. 243 virtual void EmitValue(const MCExpr *Value, unsigned Size, 244 unsigned AddrSpace = 0) = 0; 245 246 /// EmitIntValue - Special case of EmitValue that avoids the client having 247 /// to pass in a MCExpr for constant integers. 248 virtual void EmitIntValue(uint64_t Value, unsigned Size, 249 unsigned AddrSpace = 0); 250 251 252 virtual void EmitULEB128Value(const MCExpr *Value, 253 unsigned AddrSpace = 0) = 0; 254 255 virtual void EmitSLEB128Value(const MCExpr *Value, 256 unsigned AddrSpace = 0) = 0; 257 258 /// EmitULEB128Value - Special case of EmitULEB128Value that avoids the 259 /// client having to pass in a MCExpr for constant integers. 260 virtual void EmitULEB128IntValue(uint64_t Value, unsigned AddrSpace = 0); 261 262 /// EmitSLEB128Value - Special case of EmitSLEB128Value that avoids the 263 /// client having to pass in a MCExpr for constant integers. 264 virtual void EmitSLEB128IntValue(int64_t Value, unsigned AddrSpace = 0); 265 266 /// EmitSymbolValue - Special case of EmitValue that avoids the client 267 /// having to pass in a MCExpr for MCSymbols. 268 virtual void EmitSymbolValue(const MCSymbol *Sym, unsigned Size, 269 unsigned AddrSpace = 0); 270 271 /// EmitGPRel32Value - Emit the expression @p Value into the output as a 272 /// gprel32 (32-bit GP relative) value. 273 /// 274 /// This is used to implement assembler directives such as .gprel32 on 275 /// targets that support them. 276 virtual void EmitGPRel32Value(const MCExpr *Value) = 0; 277 278 /// EmitFill - Emit NumBytes bytes worth of the value specified by 279 /// FillValue. This implements directives such as '.space'. 280 virtual void EmitFill(uint64_t NumBytes, uint8_t FillValue, 281 unsigned AddrSpace); 282 283 /// EmitZeros - Emit NumBytes worth of zeros. This is a convenience 284 /// function that just wraps EmitFill. 285 void EmitZeros(uint64_t NumBytes, unsigned AddrSpace) { 286 EmitFill(NumBytes, 0, AddrSpace); 287 } 288 289 290 /// EmitValueToAlignment - Emit some number of copies of @p Value until 291 /// the byte alignment @p ByteAlignment is reached. 292 /// 293 /// If the number of bytes need to emit for the alignment is not a multiple 294 /// of @p ValueSize, then the contents of the emitted fill bytes is 295 /// undefined. 296 /// 297 /// This used to implement the .align assembler directive. 298 /// 299 /// @param ByteAlignment - The alignment to reach. This must be a power of 300 /// two on some targets. 301 /// @param Value - The value to use when filling bytes. 302 /// @param ValueSize - The size of the integer (in bytes) to emit for 303 /// @p Value. This must match a native machine width. 304 /// @param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If 305 /// the alignment cannot be reached in this many bytes, no bytes are 306 /// emitted. 307 virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0, 308 unsigned ValueSize = 1, 309 unsigned MaxBytesToEmit = 0) = 0; 310 311 /// EmitCodeAlignment - Emit nops until the byte alignment @p ByteAlignment 312 /// is reached. 313 /// 314 /// This used to align code where the alignment bytes may be executed. This 315 /// can emit different bytes for different sizes to optimize execution. 316 /// 317 /// @param ByteAlignment - The alignment to reach. This must be a power of 318 /// two on some targets. 319 /// @param MaxBytesToEmit - The maximum numbers of bytes to emit, or 0. If 320 /// the alignment cannot be reached in this many bytes, no bytes are 321 /// emitted. 322 virtual void EmitCodeAlignment(unsigned ByteAlignment, 323 unsigned MaxBytesToEmit = 0) = 0; 324 325 /// EmitValueToOffset - Emit some number of copies of @p Value until the 326 /// byte offset @p Offset is reached. 327 /// 328 /// This is used to implement assembler directives such as .org. 329 /// 330 /// @param Offset - The offset to reach. This may be an expression, but the 331 /// expression must be associated with the current section. 332 /// @param Value - The value to use when filling bytes. 333 virtual void EmitValueToOffset(const MCExpr *Offset, 334 unsigned char Value = 0) = 0; 335 336 /// @} 337 338 /// EmitFileDirective - Switch to a new logical file. This is used to 339 /// implement the '.file "foo.c"' assembler directive. 340 virtual void EmitFileDirective(StringRef Filename) = 0; 341 342 /// EmitDwarfFileDirective - Associate a filename with a specified logical 343 /// file number. This implements the DWARF2 '.file 4 "foo.c"' assembler 344 /// directive. 345 virtual bool EmitDwarfFileDirective(unsigned FileNo,StringRef Filename); 346 347 /// EmitDwarfLocDirective - This implements the DWARF2 348 // '.loc fileno lineno ...' assembler directive. 349 virtual void EmitDwarfLocDirective(unsigned FileNo, unsigned Line, 350 unsigned Column, unsigned Flags, 351 unsigned Isa, 352 unsigned Discriminator); 353 354 /// EmitInstruction - Emit the given @p Instruction into the current 355 /// section. 356 virtual void EmitInstruction(const MCInst &Inst) = 0; 357 358 /// EmitRawText - If this file is backed by a assembly streamer, this dumps 359 /// the specified string in the output .s file. This capability is 360 /// indicated by the hasRawTextSupport() predicate. By default this aborts. 361 virtual void EmitRawText(StringRef String); 362 void EmitRawText(const Twine &String); 363 364 /// Finish - Finish emission of machine code. 365 virtual void Finish() = 0; 366 }; 367 368 /// createNullStreamer - Create a dummy machine code streamer, which does 369 /// nothing. This is useful for timing the assembler front end. 370 MCStreamer *createNullStreamer(MCContext &Ctx); 371 372 /// createAsmStreamer - Create a machine code streamer which will print out 373 /// assembly for the native target, suitable for compiling with a native 374 /// assembler. 375 /// 376 /// \param InstPrint - If given, the instruction printer to use. If not given 377 /// the MCInst representation will be printed. This method takes ownership of 378 /// InstPrint. 379 /// 380 /// \param CE - If given, a code emitter to use to show the instruction 381 /// encoding inline with the assembly. This method takes ownership of \arg CE. 382 /// 383 /// \param ShowInst - Whether to show the MCInst representation inline with 384 /// the assembly. 385 MCStreamer *createAsmStreamer(MCContext &Ctx, formatted_raw_ostream &OS, 386 bool isLittleEndian, bool isVerboseAsm, 387 MCInstPrinter *InstPrint = 0, 388 MCCodeEmitter *CE = 0, 389 bool ShowInst = false); 390 391 /// createMachOStreamer - Create a machine code streamer which will generate 392 /// Mach-O format object files. 393 /// 394 /// Takes ownership of \arg TAB and \arg CE. 395 MCStreamer *createMachOStreamer(MCContext &Ctx, TargetAsmBackend &TAB, 396 raw_ostream &OS, MCCodeEmitter *CE, 397 bool RelaxAll = false); 398 399 /// createWinCOFFStreamer - Create a machine code streamer which will 400 /// generate Microsoft COFF format object files. 401 /// 402 /// Takes ownership of \arg TAB and \arg CE. 403 MCStreamer *createWinCOFFStreamer(MCContext &Ctx, 404 TargetAsmBackend &TAB, 405 MCCodeEmitter &CE, raw_ostream &OS, 406 bool RelaxAll = false); 407 408 /// createELFStreamer - Create a machine code streamer which will generate 409 /// ELF format object files. 410 MCStreamer *createELFStreamer(MCContext &Ctx, TargetAsmBackend &TAB, 411 raw_ostream &OS, MCCodeEmitter *CE, 412 bool RelaxAll = false); 413 414 /// createLoggingStreamer - Create a machine code streamer which just logs the 415 /// API calls and then dispatches to another streamer. 416 /// 417 /// The new streamer takes ownership of the \arg Child. 418 MCStreamer *createLoggingStreamer(MCStreamer *Child, raw_ostream &OS); 419 420} // end namespace llvm 421 422#endif 423