LLVM  6.0.0svn
BitstreamWriter.h
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1 //===- BitstreamWriter.h - Low-level bitstream writer interface -*- C++ -*-===//
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 // This header defines the BitstreamWriter class. This class can be used to
11 // write an arbitrary bitstream, regardless of its contents.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_BITCODE_BITSTREAMWRITER_H
16 #define LLVM_BITCODE_BITSTREAMWRITER_H
17 
18 #include "llvm/ADT/ArrayRef.h"
19 #include "llvm/ADT/Optional.h"
20 #include "llvm/ADT/SmallVector.h"
21 #include "llvm/ADT/StringRef.h"
22 #include "llvm/Bitcode/BitCodes.h"
23 #include "llvm/Support/Endian.h"
24 #include <vector>
25 
26 namespace llvm {
27 
30 
31  /// CurBit - Always between 0 and 31 inclusive, specifies the next bit to use.
32  unsigned CurBit;
33 
34  /// CurValue - The current value. Only bits < CurBit are valid.
35  uint32_t CurValue;
36 
37  /// CurCodeSize - This is the declared size of code values used for the
38  /// current block, in bits.
39  unsigned CurCodeSize;
40 
41  /// BlockInfoCurBID - When emitting a BLOCKINFO_BLOCK, this is the currently
42  /// selected BLOCK ID.
43  unsigned BlockInfoCurBID;
44 
45  /// CurAbbrevs - Abbrevs installed at in this block.
46  std::vector<std::shared_ptr<BitCodeAbbrev>> CurAbbrevs;
47 
48  struct Block {
49  unsigned PrevCodeSize;
50  size_t StartSizeWord;
51  std::vector<std::shared_ptr<BitCodeAbbrev>> PrevAbbrevs;
52  Block(unsigned PCS, size_t SSW) : PrevCodeSize(PCS), StartSizeWord(SSW) {}
53  };
54 
55  /// BlockScope - This tracks the current blocks that we have entered.
56  std::vector<Block> BlockScope;
57 
58  /// BlockInfo - This contains information emitted to BLOCKINFO_BLOCK blocks.
59  /// These describe abbreviations that all blocks of the specified ID inherit.
60  struct BlockInfo {
61  unsigned BlockID;
62  std::vector<std::shared_ptr<BitCodeAbbrev>> Abbrevs;
63  };
64  std::vector<BlockInfo> BlockInfoRecords;
65 
66  void WriteByte(unsigned char Value) {
67  Out.push_back(Value);
68  }
69 
70  void WriteWord(unsigned Value) {
71  Value = support::endian::byte_swap<uint32_t, support::little>(Value);
72  Out.append(reinterpret_cast<const char *>(&Value),
73  reinterpret_cast<const char *>(&Value + 1));
74  }
75 
76  size_t GetBufferOffset() const { return Out.size(); }
77 
78  size_t GetWordIndex() const {
79  size_t Offset = GetBufferOffset();
80  assert((Offset & 3) == 0 && "Not 32-bit aligned");
81  return Offset / 4;
82  }
83 
84 public:
86  : Out(O), CurBit(0), CurValue(0), CurCodeSize(2) {}
87 
89  assert(CurBit == 0 && "Unflushed data remaining");
90  assert(BlockScope.empty() && CurAbbrevs.empty() && "Block imbalance");
91  }
92 
93  /// \brief Retrieve the current position in the stream, in bits.
94  uint64_t GetCurrentBitNo() const { return GetBufferOffset() * 8 + CurBit; }
95 
96  /// \brief Retrieve the number of bits currently used to encode an abbrev ID.
97  unsigned GetAbbrevIDWidth() const { return CurCodeSize; }
98 
99  //===--------------------------------------------------------------------===//
100  // Basic Primitives for emitting bits to the stream.
101  //===--------------------------------------------------------------------===//
102 
103  /// Backpatch a 32-bit word in the output at the given bit offset
104  /// with the specified value.
105  void BackpatchWord(uint64_t BitNo, unsigned NewWord) {
106  using namespace llvm::support;
107  unsigned ByteNo = BitNo / 8;
108  assert((!endian::readAtBitAlignment<uint32_t, little, unaligned>(
109  &Out[ByteNo], BitNo & 7)) &&
110  "Expected to be patching over 0-value placeholders");
111  endian::writeAtBitAlignment<uint32_t, little, unaligned>(
112  &Out[ByteNo], NewWord, BitNo & 7);
113  }
114 
115  void BackpatchWord64(uint64_t BitNo, uint64_t Val) {
116  BackpatchWord(BitNo, (uint32_t)Val);
117  BackpatchWord(BitNo + 32, (uint32_t)(Val >> 32));
118  }
119 
120  void Emit(uint32_t Val, unsigned NumBits) {
121  assert(NumBits && NumBits <= 32 && "Invalid value size!");
122  assert((Val & ~(~0U >> (32-NumBits))) == 0 && "High bits set!");
123  CurValue |= Val << CurBit;
124  if (CurBit + NumBits < 32) {
125  CurBit += NumBits;
126  return;
127  }
128 
129  // Add the current word.
130  WriteWord(CurValue);
131 
132  if (CurBit)
133  CurValue = Val >> (32-CurBit);
134  else
135  CurValue = 0;
136  CurBit = (CurBit+NumBits) & 31;
137  }
138 
139  void FlushToWord() {
140  if (CurBit) {
141  WriteWord(CurValue);
142  CurBit = 0;
143  CurValue = 0;
144  }
145  }
146 
147  void EmitVBR(uint32_t Val, unsigned NumBits) {
148  assert(NumBits <= 32 && "Too many bits to emit!");
149  uint32_t Threshold = 1U << (NumBits-1);
150 
151  // Emit the bits with VBR encoding, NumBits-1 bits at a time.
152  while (Val >= Threshold) {
153  Emit((Val & ((1 << (NumBits-1))-1)) | (1 << (NumBits-1)), NumBits);
154  Val >>= NumBits-1;
155  }
156 
157  Emit(Val, NumBits);
158  }
159 
160  void EmitVBR64(uint64_t Val, unsigned NumBits) {
161  assert(NumBits <= 32 && "Too many bits to emit!");
162  if ((uint32_t)Val == Val)
163  return EmitVBR((uint32_t)Val, NumBits);
164 
165  uint32_t Threshold = 1U << (NumBits-1);
166 
167  // Emit the bits with VBR encoding, NumBits-1 bits at a time.
168  while (Val >= Threshold) {
169  Emit(((uint32_t)Val & ((1 << (NumBits-1))-1)) |
170  (1 << (NumBits-1)), NumBits);
171  Val >>= NumBits-1;
172  }
173 
174  Emit((uint32_t)Val, NumBits);
175  }
176 
177  /// EmitCode - Emit the specified code.
178  void EmitCode(unsigned Val) {
179  Emit(Val, CurCodeSize);
180  }
181 
182  //===--------------------------------------------------------------------===//
183  // Block Manipulation
184  //===--------------------------------------------------------------------===//
185 
186  /// getBlockInfo - If there is block info for the specified ID, return it,
187  /// otherwise return null.
188  BlockInfo *getBlockInfo(unsigned BlockID) {
189  // Common case, the most recent entry matches BlockID.
190  if (!BlockInfoRecords.empty() && BlockInfoRecords.back().BlockID == BlockID)
191  return &BlockInfoRecords.back();
192 
193  for (unsigned i = 0, e = static_cast<unsigned>(BlockInfoRecords.size());
194  i != e; ++i)
195  if (BlockInfoRecords[i].BlockID == BlockID)
196  return &BlockInfoRecords[i];
197  return nullptr;
198  }
199 
200  void EnterSubblock(unsigned BlockID, unsigned CodeLen) {
201  // Block header:
202  // [ENTER_SUBBLOCK, blockid, newcodelen, <align4bytes>, blocklen]
204  EmitVBR(BlockID, bitc::BlockIDWidth);
205  EmitVBR(CodeLen, bitc::CodeLenWidth);
206  FlushToWord();
207 
208  size_t BlockSizeWordIndex = GetWordIndex();
209  unsigned OldCodeSize = CurCodeSize;
210 
211  // Emit a placeholder, which will be replaced when the block is popped.
213 
214  CurCodeSize = CodeLen;
215 
216  // Push the outer block's abbrev set onto the stack, start out with an
217  // empty abbrev set.
218  BlockScope.emplace_back(OldCodeSize, BlockSizeWordIndex);
219  BlockScope.back().PrevAbbrevs.swap(CurAbbrevs);
220 
221  // If there is a blockinfo for this BlockID, add all the predefined abbrevs
222  // to the abbrev list.
223  if (BlockInfo *Info = getBlockInfo(BlockID)) {
224  CurAbbrevs.insert(CurAbbrevs.end(), Info->Abbrevs.begin(),
225  Info->Abbrevs.end());
226  }
227  }
228 
229  void ExitBlock() {
230  assert(!BlockScope.empty() && "Block scope imbalance!");
231  const Block &B = BlockScope.back();
232 
233  // Block tail:
234  // [END_BLOCK, <align4bytes>]
236  FlushToWord();
237 
238  // Compute the size of the block, in words, not counting the size field.
239  size_t SizeInWords = GetWordIndex() - B.StartSizeWord - 1;
240  uint64_t BitNo = uint64_t(B.StartSizeWord) * 32;
241 
242  // Update the block size field in the header of this sub-block.
243  BackpatchWord(BitNo, SizeInWords);
244 
245  // Restore the inner block's code size and abbrev table.
246  CurCodeSize = B.PrevCodeSize;
247  CurAbbrevs = std::move(B.PrevAbbrevs);
248  BlockScope.pop_back();
249  }
250 
251  //===--------------------------------------------------------------------===//
252  // Record Emission
253  //===--------------------------------------------------------------------===//
254 
255 private:
256  /// EmitAbbreviatedLiteral - Emit a literal value according to its abbrev
257  /// record. This is a no-op, since the abbrev specifies the literal to use.
258  template<typename uintty>
259  void EmitAbbreviatedLiteral(const BitCodeAbbrevOp &Op, uintty V) {
260  assert(Op.isLiteral() && "Not a literal");
261  // If the abbrev specifies the literal value to use, don't emit
262  // anything.
263  assert(V == Op.getLiteralValue() &&
264  "Invalid abbrev for record!");
265  }
266 
267  /// EmitAbbreviatedField - Emit a single scalar field value with the specified
268  /// encoding.
269  template<typename uintty>
270  void EmitAbbreviatedField(const BitCodeAbbrevOp &Op, uintty V) {
271  assert(!Op.isLiteral() && "Literals should use EmitAbbreviatedLiteral!");
272 
273  // Encode the value as we are commanded.
274  switch (Op.getEncoding()) {
275  default: llvm_unreachable("Unknown encoding!");
277  if (Op.getEncodingData())
278  Emit((unsigned)V, (unsigned)Op.getEncodingData());
279  break;
281  if (Op.getEncodingData())
282  EmitVBR64(V, (unsigned)Op.getEncodingData());
283  break;
285  Emit(BitCodeAbbrevOp::EncodeChar6((char)V), 6);
286  break;
287  }
288  }
289 
290  /// EmitRecordWithAbbrevImpl - This is the core implementation of the record
291  /// emission code. If BlobData is non-null, then it specifies an array of
292  /// data that should be emitted as part of the Blob or Array operand that is
293  /// known to exist at the end of the record. If Code is specified, then
294  /// it is the record code to emit before the Vals, which must not contain
295  /// the code.
296  template <typename uintty>
297  void EmitRecordWithAbbrevImpl(unsigned Abbrev, ArrayRef<uintty> Vals,
298  StringRef Blob, Optional<unsigned> Code) {
299  const char *BlobData = Blob.data();
300  unsigned BlobLen = (unsigned) Blob.size();
301  unsigned AbbrevNo = Abbrev-bitc::FIRST_APPLICATION_ABBREV;
302  assert(AbbrevNo < CurAbbrevs.size() && "Invalid abbrev #!");
303  const BitCodeAbbrev *Abbv = CurAbbrevs[AbbrevNo].get();
304 
305  EmitCode(Abbrev);
306 
307  unsigned i = 0, e = static_cast<unsigned>(Abbv->getNumOperandInfos());
308  if (Code) {
309  assert(e && "Expected non-empty abbreviation");
310  const BitCodeAbbrevOp &Op = Abbv->getOperandInfo(i++);
311 
312  if (Op.isLiteral())
313  EmitAbbreviatedLiteral(Op, Code.getValue());
314  else {
317  "Expected literal or scalar");
318  EmitAbbreviatedField(Op, Code.getValue());
319  }
320  }
321 
322  unsigned RecordIdx = 0;
323  for (; i != e; ++i) {
324  const BitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
325  if (Op.isLiteral()) {
326  assert(RecordIdx < Vals.size() && "Invalid abbrev/record");
327  EmitAbbreviatedLiteral(Op, Vals[RecordIdx]);
328  ++RecordIdx;
329  } else if (Op.getEncoding() == BitCodeAbbrevOp::Array) {
330  // Array case.
331  assert(i + 2 == e && "array op not second to last?");
332  const BitCodeAbbrevOp &EltEnc = Abbv->getOperandInfo(++i);
333 
334  // If this record has blob data, emit it, otherwise we must have record
335  // entries to encode this way.
336  if (BlobData) {
337  assert(RecordIdx == Vals.size() &&
338  "Blob data and record entries specified for array!");
339  // Emit a vbr6 to indicate the number of elements present.
340  EmitVBR(static_cast<uint32_t>(BlobLen), 6);
341 
342  // Emit each field.
343  for (unsigned i = 0; i != BlobLen; ++i)
344  EmitAbbreviatedField(EltEnc, (unsigned char)BlobData[i]);
345 
346  // Know that blob data is consumed for assertion below.
347  BlobData = nullptr;
348  } else {
349  // Emit a vbr6 to indicate the number of elements present.
350  EmitVBR(static_cast<uint32_t>(Vals.size()-RecordIdx), 6);
351 
352  // Emit each field.
353  for (unsigned e = Vals.size(); RecordIdx != e; ++RecordIdx)
354  EmitAbbreviatedField(EltEnc, Vals[RecordIdx]);
355  }
356  } else if (Op.getEncoding() == BitCodeAbbrevOp::Blob) {
357  // If this record has blob data, emit it, otherwise we must have record
358  // entries to encode this way.
359 
360  if (BlobData) {
361  assert(RecordIdx == Vals.size() &&
362  "Blob data and record entries specified for blob operand!");
363 
364  assert(Blob.data() == BlobData && "BlobData got moved");
365  assert(Blob.size() == BlobLen && "BlobLen got changed");
366  emitBlob(Blob);
367  BlobData = nullptr;
368  } else {
369  emitBlob(Vals.slice(RecordIdx));
370  }
371  } else { // Single scalar field.
372  assert(RecordIdx < Vals.size() && "Invalid abbrev/record");
373  EmitAbbreviatedField(Op, Vals[RecordIdx]);
374  ++RecordIdx;
375  }
376  }
377  assert(RecordIdx == Vals.size() && "Not all record operands emitted!");
378  assert(BlobData == nullptr &&
379  "Blob data specified for record that doesn't use it!");
380  }
381 
382 public:
383  /// Emit a blob, including flushing before and tail-padding.
384  template <class UIntTy>
385  void emitBlob(ArrayRef<UIntTy> Bytes, bool ShouldEmitSize = true) {
386  // Emit a vbr6 to indicate the number of elements present.
387  if (ShouldEmitSize)
388  EmitVBR(static_cast<uint32_t>(Bytes.size()), 6);
389 
390  // Flush to a 32-bit alignment boundary.
391  FlushToWord();
392 
393  // Emit literal bytes.
394  for (const auto &B : Bytes) {
395  assert(isUInt<8>(B) && "Value too large to emit as byte");
396  WriteByte((unsigned char)B);
397  }
398 
399  // Align end to 32-bits.
400  while (GetBufferOffset() & 3)
401  WriteByte(0);
402  }
403  void emitBlob(StringRef Bytes, bool ShouldEmitSize = true) {
404  emitBlob(makeArrayRef((const uint8_t *)Bytes.data(), Bytes.size()),
405  ShouldEmitSize);
406  }
407 
408  /// EmitRecord - Emit the specified record to the stream, using an abbrev if
409  /// we have one to compress the output.
410  template <typename Container>
411  void EmitRecord(unsigned Code, const Container &Vals, unsigned Abbrev = 0) {
412  if (!Abbrev) {
413  // If we don't have an abbrev to use, emit this in its fully unabbreviated
414  // form.
415  auto Count = static_cast<uint32_t>(makeArrayRef(Vals).size());
417  EmitVBR(Code, 6);
418  EmitVBR(Count, 6);
419  for (unsigned i = 0, e = Count; i != e; ++i)
420  EmitVBR64(Vals[i], 6);
421  return;
422  }
423 
424  EmitRecordWithAbbrevImpl(Abbrev, makeArrayRef(Vals), StringRef(), Code);
425  }
426 
427  /// EmitRecordWithAbbrev - Emit a record with the specified abbreviation.
428  /// Unlike EmitRecord, the code for the record should be included in Vals as
429  /// the first entry.
430  template <typename Container>
431  void EmitRecordWithAbbrev(unsigned Abbrev, const Container &Vals) {
432  EmitRecordWithAbbrevImpl(Abbrev, makeArrayRef(Vals), StringRef(), None);
433  }
434 
435  /// EmitRecordWithBlob - Emit the specified record to the stream, using an
436  /// abbrev that includes a blob at the end. The blob data to emit is
437  /// specified by the pointer and length specified at the end. In contrast to
438  /// EmitRecord, this routine expects that the first entry in Vals is the code
439  /// of the record.
440  template <typename Container>
441  void EmitRecordWithBlob(unsigned Abbrev, const Container &Vals,
442  StringRef Blob) {
443  EmitRecordWithAbbrevImpl(Abbrev, makeArrayRef(Vals), Blob, None);
444  }
445  template <typename Container>
446  void EmitRecordWithBlob(unsigned Abbrev, const Container &Vals,
447  const char *BlobData, unsigned BlobLen) {
448  return EmitRecordWithAbbrevImpl(Abbrev, makeArrayRef(Vals),
449  StringRef(BlobData, BlobLen), None);
450  }
451 
452  /// EmitRecordWithArray - Just like EmitRecordWithBlob, works with records
453  /// that end with an array.
454  template <typename Container>
455  void EmitRecordWithArray(unsigned Abbrev, const Container &Vals,
456  StringRef Array) {
457  EmitRecordWithAbbrevImpl(Abbrev, makeArrayRef(Vals), Array, None);
458  }
459  template <typename Container>
460  void EmitRecordWithArray(unsigned Abbrev, const Container &Vals,
461  const char *ArrayData, unsigned ArrayLen) {
462  return EmitRecordWithAbbrevImpl(Abbrev, makeArrayRef(Vals),
463  StringRef(ArrayData, ArrayLen), None);
464  }
465 
466  //===--------------------------------------------------------------------===//
467  // Abbrev Emission
468  //===--------------------------------------------------------------------===//
469 
470 private:
471  // Emit the abbreviation as a DEFINE_ABBREV record.
472  void EncodeAbbrev(const BitCodeAbbrev &Abbv) {
474  EmitVBR(Abbv.getNumOperandInfos(), 5);
475  for (unsigned i = 0, e = static_cast<unsigned>(Abbv.getNumOperandInfos());
476  i != e; ++i) {
477  const BitCodeAbbrevOp &Op = Abbv.getOperandInfo(i);
478  Emit(Op.isLiteral(), 1);
479  if (Op.isLiteral()) {
480  EmitVBR64(Op.getLiteralValue(), 8);
481  } else {
482  Emit(Op.getEncoding(), 3);
483  if (Op.hasEncodingData())
484  EmitVBR64(Op.getEncodingData(), 5);
485  }
486  }
487  }
488 public:
489 
490  /// EmitAbbrev - This emits an abbreviation to the stream. Note that this
491  /// method takes ownership of the specified abbrev.
492  unsigned EmitAbbrev(std::shared_ptr<BitCodeAbbrev> Abbv) {
493  // Emit the abbreviation as a record.
494  EncodeAbbrev(*Abbv);
495  CurAbbrevs.push_back(std::move(Abbv));
496  return static_cast<unsigned>(CurAbbrevs.size())-1 +
498  }
499 
500  //===--------------------------------------------------------------------===//
501  // BlockInfo Block Emission
502  //===--------------------------------------------------------------------===//
503 
504  /// EnterBlockInfoBlock - Start emitting the BLOCKINFO_BLOCK.
507  BlockInfoCurBID = ~0U;
508  BlockInfoRecords.clear();
509  }
510 private:
511  /// SwitchToBlockID - If we aren't already talking about the specified block
512  /// ID, emit a BLOCKINFO_CODE_SETBID record.
513  void SwitchToBlockID(unsigned BlockID) {
514  if (BlockInfoCurBID == BlockID) return;
516  V.push_back(BlockID);
518  BlockInfoCurBID = BlockID;
519  }
520 
521  BlockInfo &getOrCreateBlockInfo(unsigned BlockID) {
522  if (BlockInfo *BI = getBlockInfo(BlockID))
523  return *BI;
524 
525  // Otherwise, add a new record.
526  BlockInfoRecords.emplace_back();
527  BlockInfoRecords.back().BlockID = BlockID;
528  return BlockInfoRecords.back();
529  }
530 
531 public:
532 
533  /// EmitBlockInfoAbbrev - Emit a DEFINE_ABBREV record for the specified
534  /// BlockID.
535  unsigned EmitBlockInfoAbbrev(unsigned BlockID, std::shared_ptr<BitCodeAbbrev> Abbv) {
536  SwitchToBlockID(BlockID);
537  EncodeAbbrev(*Abbv);
538 
539  // Add the abbrev to the specified block record.
540  BlockInfo &Info = getOrCreateBlockInfo(BlockID);
541  Info.Abbrevs.push_back(std::move(Abbv));
542 
543  return Info.Abbrevs.size()-1+bitc::FIRST_APPLICATION_ABBREV;
544  }
545 };
546 
547 
548 } // End llvm namespace
549 
550 #endif
Encoding getEncoding() const
Definition: BitCodes.h:118
void push_back(const T &Elt)
Definition: SmallVector.h:212
BLOCKINFO_BLOCK is used to define metadata about blocks, for example, standard abbrevs that should be...
Definition: BitCodes.h:69
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
LLVM_ATTRIBUTE_ALWAYS_INLINE size_type size() const
Definition: SmallVector.h:136
BitCodeAbbrev - This class represents an abbreviation record.
Definition: BitCodes.h:168
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE size_t size() const
size - Get the string size.
Definition: StringRef.h:138
uint64_t GetCurrentBitNo() const
Retrieve the current position in the stream, in bits.
unsigned GetAbbrevIDWidth() const
Retrieve the number of bits currently used to encode an abbrev ID.
uint64_t getLiteralValue() const
Definition: BitCodes.h:115
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE const char * data() const
data - Get a pointer to the start of the string (which may not be null terminated).
Definition: StringRef.h:128
static unsigned EncodeChar6(char C)
Definition: BitCodes.h:146
void EmitRecordWithArray(unsigned Abbrev, const Container &Vals, const char *ArrayData, unsigned ArrayLen)
ArrayRef< T > makeArrayRef(const T &OneElt)
Construct an ArrayRef from a single element.
Definition: ArrayRef.h:451
void BackpatchWord(uint64_t BitNo, unsigned NewWord)
Backpatch a 32-bit word in the output at the given bit offset with the specified value.
void Emit(uint32_t Val, unsigned NumBits)
void EnterBlockInfoBlock()
EnterBlockInfoBlock - Start emitting the BLOCKINFO_BLOCK.
void EmitRecordWithAbbrev(unsigned Abbrev, const Container &Vals)
EmitRecordWithAbbrev - Emit a record with the specified abbreviation.
const T & getValue() const LLVM_LVALUE_FUNCTION
Definition: Optional.h:127
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:33
const BitCodeAbbrevOp & getOperandInfo(unsigned N) const
Definition: BitCodes.h:175
void EmitRecord(unsigned Code, const Container &Vals, unsigned Abbrev=0)
EmitRecord - Emit the specified record to the stream, using an abbrev if we have one to compress the ...
void EnterSubblock(unsigned BlockID, unsigned CodeLen)
void BackpatchWord64(uint64_t BitNo, uint64_t Val)
void EmitCode(unsigned Val)
EmitCode - Emit the specified code.
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
constexpr bool isUInt< 8 >(uint64_t x)
Definition: MathExtras.h:335
size_t size() const
size - Get the array size.
Definition: ArrayRef.h:149
void EmitRecordWithBlob(unsigned Abbrev, const Container &Vals, const char *BlobData, unsigned BlobLen)
BitCodeAbbrevOp - This describes one or more operands in an abbreviation.
Definition: BitCodes.h:94
void EmitVBR(uint32_t Val, unsigned NumBits)
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
void emitBlob(StringRef Bytes, bool ShouldEmitSize=true)
unsigned EmitAbbrev(std::shared_ptr< BitCodeAbbrev > Abbv)
EmitAbbrev - This emits an abbreviation to the stream.
BlockInfo * getBlockInfo(unsigned BlockID)
getBlockInfo - If there is block info for the specified ID, return it, otherwise return null...
void EmitRecordWithArray(unsigned Abbrev, const Container &Vals, StringRef Array)
EmitRecordWithArray - Just like EmitRecordWithBlob, works with records that end with an array...
void EmitRecordWithBlob(unsigned Abbrev, const Container &Vals, StringRef Blob)
EmitRecordWithBlob - Emit the specified record to the stream, using an abbrev that includes a blob at...
DEFINE_ABBREV - Defines an abbrev for the current block.
Definition: BitCodes.h:53
ArrayRef< T > slice(size_t N, size_t M) const
slice(n, m) - Chop off the first N elements of the array, and keep M elements in the array...
Definition: ArrayRef.h:179
void append(in_iter in_start, in_iter in_end)
Add the specified range to the end of the SmallVector.
Definition: SmallVector.h:398
unsigned getNumOperandInfos() const
Definition: BitCodes.h:172
uint64_t getEncodingData() const
Definition: BitCodes.h:119
bool isLiteral() const
Definition: BitCodes.h:111
BitstreamWriter(SmallVectorImpl< char > &O)
bool hasEncodingData() const
Definition: BitCodes.h:124
static int const Threshold
TODO: Write a new FunctionPass AliasAnalysis so that it can keep a cache.
void EmitVBR64(uint64_t Val, unsigned NumBits)
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
LLVM Value Representation.
Definition: Value.h:73
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
void emitBlob(ArrayRef< UIntTy > Bytes, bool ShouldEmitSize=true)
Emit a blob, including flushing before and tail-padding.
unsigned EmitBlockInfoAbbrev(unsigned BlockID, std::shared_ptr< BitCodeAbbrev > Abbv)
EmitBlockInfoAbbrev - Emit a DEFINE_ABBREV record for the specified BlockID.