LLVM  9.0.0svn
LazyRandomTypeCollection.cpp
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1 //===- LazyRandomTypeCollection.cpp ---------------------------------------===//
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 
11 #include "llvm/ADT/ArrayRef.h"
12 #include "llvm/ADT/None.h"
13 #include "llvm/ADT/StringExtras.h"
14 #include "llvm/ADT/StringRef.h"
19 #include "llvm/Support/Endian.h"
20 #include "llvm/Support/Error.h"
21 #include <algorithm>
22 #include <cassert>
23 #include <cstdint>
24 #include <iterator>
25 
26 using namespace llvm;
27 using namespace llvm::codeview;
28 
29 static void error(Error &&EC) {
30  assert(!static_cast<bool>(EC));
31  if (EC)
32  consumeError(std::move(EC));
33 }
34 
36  : LazyRandomTypeCollection(CVTypeArray(), RecordCountHint,
37  PartialOffsetArray()) {}
38 
40  const CVTypeArray &Types, uint32_t RecordCountHint,
41  PartialOffsetArray PartialOffsets)
42  : NameStorage(Allocator), Types(Types), PartialOffsets(PartialOffsets) {
43  Records.resize(RecordCountHint);
44 }
45 
47  uint32_t RecordCountHint)
48  : LazyRandomTypeCollection(RecordCountHint) {
49 }
50 
52  uint32_t RecordCountHint)
54  makeArrayRef(Data.bytes_begin(), Data.bytes_end()), RecordCountHint) {
55 }
56 
58  uint32_t NumRecords)
59  : LazyRandomTypeCollection(Types, NumRecords, PartialOffsetArray()) {}
60 
62  uint32_t RecordCountHint) {
63  Count = 0;
64  PartialOffsets = PartialOffsetArray();
65 
66  error(Reader.readArray(Types, Reader.bytesRemaining()));
67 
68  // Clear and then resize, to make sure existing data gets destroyed.
69  Records.clear();
70  Records.resize(RecordCountHint);
71 }
72 
73 void LazyRandomTypeCollection::reset(StringRef Data, uint32_t RecordCountHint) {
74  BinaryStreamReader Reader(Data, support::little);
75  reset(Reader, RecordCountHint);
76 }
77 
79  uint32_t RecordCountHint) {
80  BinaryStreamReader Reader(Data, support::little);
81  reset(Reader, RecordCountHint);
82 }
83 
85  error(ensureTypeExists(Index));
86  assert(contains(Index));
87 
88  return Records[Index.toArrayIndex()].Offset;
89 }
90 
92  assert(!Index.isSimple());
93 
94  auto EC = ensureTypeExists(Index);
95  error(std::move(EC));
96  assert(contains(Index));
97 
98  return Records[Index.toArrayIndex()].Type;
99 }
100 
102  if (Index.isSimple())
103  return None;
104 
105  if (auto EC = ensureTypeExists(Index)) {
106  consumeError(std::move(EC));
107  return None;
108  }
109 
110  assert(contains(Index));
111  return Records[Index.toArrayIndex()].Type;
112 }
113 
115  if (Index.isNoneType() || Index.isSimple())
116  return TypeIndex::simpleTypeName(Index);
117 
118  // Try to make sure the type exists. Even if it doesn't though, it may be
119  // because we're dumping a symbol stream with no corresponding type stream
120  // present, in which case we still want to be able to print <unknown UDT>
121  // for the type names.
122  if (auto EC = ensureTypeExists(Index)) {
123  consumeError(std::move(EC));
124  return "<unknown UDT>";
125  }
126 
127  uint32_t I = Index.toArrayIndex();
128  ensureCapacityFor(Index);
129  if (Records[I].Name.data() == nullptr) {
130  StringRef Result = NameStorage.save(computeTypeName(*this, Index));
131  Records[I].Name = Result;
132  }
133  return Records[I].Name;
134 }
135 
137  if (Index.isSimple() || Index.isNoneType())
138  return false;
139 
140  if (Records.size() <= Index.toArrayIndex())
141  return false;
142  if (!Records[Index.toArrayIndex()].Type.valid())
143  return false;
144  return true;
145 }
146 
148 
149 uint32_t LazyRandomTypeCollection::capacity() { return Records.size(); }
150 
151 Error LazyRandomTypeCollection::ensureTypeExists(TypeIndex TI) {
152  if (contains(TI))
153  return Error::success();
154 
155  return visitRangeForType(TI);
156 }
157 
158 void LazyRandomTypeCollection::ensureCapacityFor(TypeIndex Index) {
159  assert(!Index.isSimple());
160  uint32_t MinSize = Index.toArrayIndex() + 1;
161 
162  if (MinSize <= capacity())
163  return;
164 
165  uint32_t NewCapacity = MinSize * 3 / 2;
166 
167  assert(NewCapacity > capacity());
168  Records.resize(NewCapacity);
169 }
170 
171 Error LazyRandomTypeCollection::visitRangeForType(TypeIndex TI) {
172  assert(!TI.isSimple());
173  if (PartialOffsets.empty())
174  return fullScanForType(TI);
175 
176  auto Next = std::upper_bound(PartialOffsets.begin(), PartialOffsets.end(), TI,
177  [](TypeIndex Value, const TypeIndexOffset &IO) {
178  return Value < IO.Type;
179  });
180 
181  assert(Next != PartialOffsets.begin());
182  auto Prev = std::prev(Next);
183 
184  TypeIndex TIB = Prev->Type;
185  if (contains(TIB)) {
186  // They've asked us to fetch a type index, but the entry we found in the
187  // partial offsets array has already been visited. Since we visit an entire
188  // block every time, that means this record should have been previously
189  // discovered. Ultimately, this means this is a request for a non-existant
190  // type index.
191  return make_error<CodeViewError>("Invalid type index");
192  }
193 
194  TypeIndex TIE;
195  if (Next == PartialOffsets.end()) {
197  } else {
198  TIE = Next->Type;
199  }
200 
201  visitRange(TIB, Prev->Offset, TIE);
202  return Error::success();
203 }
204 
207  if (auto EC = ensureTypeExists(TI)) {
208  consumeError(std::move(EC));
209  return None;
210  }
211  return TI;
212 }
213 
215  // We can't be sure how long this type stream is, given that the initial count
216  // given to the constructor is just a hint. So just try to make sure the next
217  // record exists, and if anything goes wrong, we must be at the end.
218  if (auto EC = ensureTypeExists(Prev + 1)) {
219  consumeError(std::move(EC));
220  return None;
221  }
222 
223  return Prev + 1;
224 }
225 
226 Error LazyRandomTypeCollection::fullScanForType(TypeIndex TI) {
227  assert(!TI.isSimple());
228  assert(PartialOffsets.empty());
229 
230  TypeIndex CurrentTI = TypeIndex::fromArrayIndex(0);
231  auto Begin = Types.begin();
232 
233  if (Count > 0) {
234  // In the case of type streams which we don't know the number of records of,
235  // it's possible to search for a type index triggering a full scan, but then
236  // later additional records are added since we didn't know how many there
237  // would be until we did a full visitation, then you try to access the new
238  // type triggering another full scan. To avoid this, we assume that if the
239  // database has some records, this must be what's going on. We can also
240  // assume that this index must be larger than the largest type index we've
241  // visited, so we start from there and scan forward.
242  uint32_t Offset = Records[LargestTypeIndex.toArrayIndex()].Offset;
243  CurrentTI = LargestTypeIndex + 1;
244  Begin = Types.at(Offset);
245  ++Begin;
246  }
247 
248  auto End = Types.end();
249  while (Begin != End) {
250  ensureCapacityFor(CurrentTI);
251  LargestTypeIndex = std::max(LargestTypeIndex, CurrentTI);
252  auto Idx = CurrentTI.toArrayIndex();
253  Records[Idx].Type = *Begin;
254  Records[Idx].Offset = Begin.offset();
255  ++Count;
256  ++Begin;
257  ++CurrentTI;
258  }
259  if (CurrentTI <= TI) {
260  return make_error<CodeViewError>("Type Index does not exist!");
261  }
262  return Error::success();
263 }
264 
265 void LazyRandomTypeCollection::visitRange(TypeIndex Begin, uint32_t BeginOffset,
266  TypeIndex End) {
267  auto RI = Types.at(BeginOffset);
268  assert(RI != Types.end());
269 
270  ensureCapacityFor(End);
271  while (Begin != End) {
272  LargestTypeIndex = std::max(LargestTypeIndex, Begin);
273  auto Idx = Begin.toArrayIndex();
274  Records[Idx].Type = *RI;
275  Records[Idx].Offset = RI.offset();
276  ++Count;
277  ++Begin;
278  ++RI;
279  }
280 }
GCNRegPressure max(const GCNRegPressure &P1, const GCNRegPressure &P2)
This class represents lattice values for constants.
Definition: AllocatorList.h:24
Iterator end() const
std::string computeTypeName(TypeCollection &Types, TypeIndex Index)
Definition: RecordName.cpp:249
Optional< TypeIndex > getNext(TypeIndex Prev) override
amdgpu Simplify well known AMD library false Value Value const Twine & Name
ArrayRef< T > makeArrayRef(const T &OneElt)
Construct an ArrayRef from a single element.
Definition: ArrayRef.h:451
bool isNoneType() const
Definition: TypeIndex.h:116
void reset(ArrayRef< uint8_t > Data, uint32_t RecordCountHint)
static void error(Error &&EC)
A 32-bit type reference.
Definition: TypeIndex.h:96
uint32_t toArrayIndex() const
Definition: TypeIndex.h:118
static TypeIndex fromArrayIndex(uint32_t Index)
Definition: TypeIndex.h:123
static StringRef simpleTypeName(TypeIndex TI)
Definition: TypeIndex.cpp:71
Optional< CVType > tryGetType(TypeIndex Index)
void consumeError(Error Err)
Consume a Error without doing anything.
Definition: Error.h:982
StringRef getTypeName(TypeIndex Index) override
static ErrorSuccess success()
Create a success value.
Definition: Error.h:327
StringRef save(const char *S)
Definition: StringSaver.h:29
#define I(x, y, z)
Definition: MD5.cpp:58
uint32_t bytesRemaining() const
auto upper_bound(R &&Range, ForwardIt I) -> decltype(adl_begin(Range))
Provide wrappers to std::upper_bound which take ranges instead of having to pass begin/end explicitly...
Definition: STLExtras.h:1295
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
FixedStreamArrayIterator< T > end() const
Iterator at(uint32_t Offset) const
given an offset into the array&#39;s underlying stream, return an iterator to the record at that offset...
Iterator begin(bool *HadError=nullptr) const
LLVM Value Representation.
Definition: Value.h:73
Lightweight error class with error context and mandatory checking.
Definition: Error.h:158
Provides read only access to a subclass of BinaryStream.
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
FixedStreamArrayIterator< T > begin() const
Error readArray(ArrayRef< T > &Array, uint32_t NumElements)
Get a reference to a NumElements element array of objects of type T from the underlying stream as if ...
Provides amortized O(1) random access to a CodeView type stream.