1//===-- DebugLoc.cpp - Implement DebugLoc class ---------------------------===//
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/IR/DebugLoc.h"
11#include "LLVMContextImpl.h"
12#include "llvm/ADT/DenseMapInfo.h"
13#include "llvm/IR/DebugInfo.h"
14using namespace llvm;
15
16//===----------------------------------------------------------------------===//
17// DebugLoc Implementation
18//===----------------------------------------------------------------------===//
19
20MDNode *DebugLoc::getScope(const LLVMContext &Ctx) const {
21  if (ScopeIdx == 0) return nullptr;
22
23  if (ScopeIdx > 0) {
24    // Positive ScopeIdx is an index into ScopeRecords, which has no inlined-at
25    // position specified.
26    assert(unsigned(ScopeIdx) <= Ctx.pImpl->ScopeRecords.size() &&
27           "Invalid ScopeIdx!");
28    return Ctx.pImpl->ScopeRecords[ScopeIdx-1].get();
29  }
30
31  // Otherwise, the index is in the ScopeInlinedAtRecords array.
32  assert(unsigned(-ScopeIdx) <= Ctx.pImpl->ScopeInlinedAtRecords.size() &&
33         "Invalid ScopeIdx");
34  return Ctx.pImpl->ScopeInlinedAtRecords[-ScopeIdx-1].first.get();
35}
36
37MDNode *DebugLoc::getInlinedAt(const LLVMContext &Ctx) const {
38  // Positive ScopeIdx is an index into ScopeRecords, which has no inlined-at
39  // position specified.  Zero is invalid.
40  if (ScopeIdx >= 0) return nullptr;
41
42  // Otherwise, the index is in the ScopeInlinedAtRecords array.
43  assert(unsigned(-ScopeIdx) <= Ctx.pImpl->ScopeInlinedAtRecords.size() &&
44         "Invalid ScopeIdx");
45  return Ctx.pImpl->ScopeInlinedAtRecords[-ScopeIdx-1].second.get();
46}
47
48/// Return both the Scope and the InlinedAt values.
49void DebugLoc::getScopeAndInlinedAt(MDNode *&Scope, MDNode *&IA,
50                                    const LLVMContext &Ctx) const {
51  if (ScopeIdx == 0) {
52    Scope = IA = nullptr;
53    return;
54  }
55
56  if (ScopeIdx > 0) {
57    // Positive ScopeIdx is an index into ScopeRecords, which has no inlined-at
58    // position specified.
59    assert(unsigned(ScopeIdx) <= Ctx.pImpl->ScopeRecords.size() &&
60           "Invalid ScopeIdx!");
61    Scope = Ctx.pImpl->ScopeRecords[ScopeIdx-1].get();
62    IA = nullptr;
63    return;
64  }
65
66  // Otherwise, the index is in the ScopeInlinedAtRecords array.
67  assert(unsigned(-ScopeIdx) <= Ctx.pImpl->ScopeInlinedAtRecords.size() &&
68         "Invalid ScopeIdx");
69  Scope = Ctx.pImpl->ScopeInlinedAtRecords[-ScopeIdx-1].first.get();
70  IA    = Ctx.pImpl->ScopeInlinedAtRecords[-ScopeIdx-1].second.get();
71}
72
73MDNode *DebugLoc::getScopeNode(const LLVMContext &Ctx) const {
74  if (MDNode *InlinedAt = getInlinedAt(Ctx))
75    return DebugLoc::getFromDILocation(InlinedAt).getScopeNode(Ctx);
76  return getScope(Ctx);
77}
78
79DebugLoc DebugLoc::getFnDebugLoc(const LLVMContext &Ctx) const {
80  const MDNode *Scope = getScopeNode(Ctx);
81  DISubprogram SP = getDISubprogram(Scope);
82  if (SP.isSubprogram()) {
83    // Check for number of operands since the compatibility is
84    // cheap here.  FIXME: Name the magic constant.
85    if (SP->getNumOperands() > 19)
86      return DebugLoc::get(SP.getScopeLineNumber(), 0, SP);
87    else
88      return DebugLoc::get(SP.getLineNumber(), 0, SP);
89  }
90
91  return DebugLoc();
92}
93
94DebugLoc DebugLoc::get(unsigned Line, unsigned Col,
95                       MDNode *Scope, MDNode *InlinedAt) {
96  DebugLoc Result;
97
98  // If no scope is available, this is an unknown location.
99  if (!Scope) return Result;
100
101  // Saturate line and col to "unknown".
102  if (Col > 255) Col = 0;
103  if (Line >= (1 << 24)) Line = 0;
104  Result.LineCol = Line | (Col << 24);
105
106  LLVMContext &Ctx = Scope->getContext();
107
108  // If there is no inlined-at location, use the ScopeRecords array.
109  if (!InlinedAt)
110    Result.ScopeIdx = Ctx.pImpl->getOrAddScopeRecordIdxEntry(Scope, 0);
111  else
112    Result.ScopeIdx = Ctx.pImpl->getOrAddScopeInlinedAtIdxEntry(Scope,
113                                                                InlinedAt, 0);
114
115  return Result;
116}
117
118/// getAsMDNode - This method converts the compressed DebugLoc node into a
119/// DILocation-compatible MDNode.
120MDNode *DebugLoc::getAsMDNode(const LLVMContext &Ctx) const {
121  if (isUnknown()) return nullptr;
122
123  MDNode *Scope, *IA;
124  getScopeAndInlinedAt(Scope, IA, Ctx);
125  assert(Scope && "If scope is null, this should be isUnknown()");
126
127  LLVMContext &Ctx2 = Scope->getContext();
128  Type *Int32 = Type::getInt32Ty(Ctx2);
129  Value *Elts[] = {
130    ConstantInt::get(Int32, getLine()), ConstantInt::get(Int32, getCol()),
131    Scope, IA
132  };
133  return MDNode::get(Ctx2, Elts);
134}
135
136/// getFromDILocation - Translate the DILocation quad into a DebugLoc.
137DebugLoc DebugLoc::getFromDILocation(MDNode *N) {
138  DILocation Loc(N);
139  MDNode *Scope = Loc.getScope();
140  if (!Scope) return DebugLoc();
141  return get(Loc.getLineNumber(), Loc.getColumnNumber(), Scope,
142             Loc.getOrigLocation());
143}
144
145/// getFromDILexicalBlock - Translate the DILexicalBlock into a DebugLoc.
146DebugLoc DebugLoc::getFromDILexicalBlock(MDNode *N) {
147  DILexicalBlock LexBlock(N);
148  MDNode *Scope = LexBlock.getContext();
149  if (!Scope) return DebugLoc();
150  return get(LexBlock.getLineNumber(), LexBlock.getColumnNumber(), Scope,
151             nullptr);
152}
153
154void DebugLoc::dump(const LLVMContext &Ctx) const {
155#ifndef NDEBUG
156  if (!isUnknown()) {
157    dbgs() << getLine();
158    if (getCol() != 0)
159      dbgs() << ',' << getCol();
160    DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(getInlinedAt(Ctx));
161    if (!InlinedAtDL.isUnknown()) {
162      dbgs() << " @ ";
163      InlinedAtDL.dump(Ctx);
164    } else
165      dbgs() << "\n";
166  }
167#endif
168}
169
170void DebugLoc::print(const LLVMContext &Ctx, raw_ostream &OS) const {
171  if (!isUnknown()) {
172    // Print source line info.
173    DIScope Scope(getScope(Ctx));
174    assert((!Scope || Scope.isScope()) &&
175           "Scope of a DebugLoc should be null or a DIScope.");
176    if (Scope)
177      OS << Scope.getFilename();
178    else
179      OS << "<unknown>";
180    OS << ':' << getLine();
181    if (getCol() != 0)
182      OS << ':' << getCol();
183    DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(getInlinedAt(Ctx));
184    if (!InlinedAtDL.isUnknown()) {
185      OS << " @[ ";
186      InlinedAtDL.print(Ctx, OS);
187      OS << " ]";
188    }
189  }
190}
191
192//===----------------------------------------------------------------------===//
193// DenseMap specialization
194//===----------------------------------------------------------------------===//
195
196unsigned DenseMapInfo<DebugLoc>::getHashValue(const DebugLoc &Key) {
197  return static_cast<unsigned>(hash_combine(Key.LineCol, Key.ScopeIdx));
198}
199
200//===----------------------------------------------------------------------===//
201// LLVMContextImpl Implementation
202//===----------------------------------------------------------------------===//
203
204int LLVMContextImpl::getOrAddScopeRecordIdxEntry(MDNode *Scope,
205                                                 int ExistingIdx) {
206  // If we already have an entry for this scope, return it.
207  int &Idx = ScopeRecordIdx[Scope];
208  if (Idx) return Idx;
209
210  // If we don't have an entry, but ExistingIdx is specified, use it.
211  if (ExistingIdx)
212    return Idx = ExistingIdx;
213
214  // Otherwise add a new entry.
215
216  // Start out ScopeRecords with a minimal reasonable size to avoid
217  // excessive reallocation starting out.
218  if (ScopeRecords.empty())
219    ScopeRecords.reserve(128);
220
221  // Index is biased by 1 for index.
222  Idx = ScopeRecords.size()+1;
223  ScopeRecords.push_back(DebugRecVH(Scope, this, Idx));
224  return Idx;
225}
226
227int LLVMContextImpl::getOrAddScopeInlinedAtIdxEntry(MDNode *Scope, MDNode *IA,
228                                                    int ExistingIdx) {
229  // If we already have an entry, return it.
230  int &Idx = ScopeInlinedAtIdx[std::make_pair(Scope, IA)];
231  if (Idx) return Idx;
232
233  // If we don't have an entry, but ExistingIdx is specified, use it.
234  if (ExistingIdx)
235    return Idx = ExistingIdx;
236
237  // Start out ScopeInlinedAtRecords with a minimal reasonable size to avoid
238  // excessive reallocation starting out.
239  if (ScopeInlinedAtRecords.empty())
240    ScopeInlinedAtRecords.reserve(128);
241
242  // Index is biased by 1 and negated.
243  Idx = -ScopeInlinedAtRecords.size()-1;
244  ScopeInlinedAtRecords.push_back(std::make_pair(DebugRecVH(Scope, this, Idx),
245                                                 DebugRecVH(IA, this, Idx)));
246  return Idx;
247}
248
249
250//===----------------------------------------------------------------------===//
251// DebugRecVH Implementation
252//===----------------------------------------------------------------------===//
253
254/// deleted - The MDNode this is pointing to got deleted, so this pointer needs
255/// to drop to null and we need remove our entry from the DenseMap.
256void DebugRecVH::deleted() {
257  // If this is a non-canonical reference, just drop the value to null, we know
258  // it doesn't have a map entry.
259  if (Idx == 0) {
260    setValPtr(nullptr);
261    return;
262  }
263
264  MDNode *Cur = get();
265
266  // If the index is positive, it is an entry in ScopeRecords.
267  if (Idx > 0) {
268    assert(Ctx->ScopeRecordIdx[Cur] == Idx && "Mapping out of date!");
269    Ctx->ScopeRecordIdx.erase(Cur);
270    // Reset this VH to null and we're done.
271    setValPtr(nullptr);
272    Idx = 0;
273    return;
274  }
275
276  // Otherwise, it is an entry in ScopeInlinedAtRecords, we don't know if it
277  // is the scope or the inlined-at record entry.
278  assert(unsigned(-Idx-1) < Ctx->ScopeInlinedAtRecords.size());
279  std::pair<DebugRecVH, DebugRecVH> &Entry = Ctx->ScopeInlinedAtRecords[-Idx-1];
280  assert((this == &Entry.first || this == &Entry.second) &&
281         "Mapping out of date!");
282
283  MDNode *OldScope = Entry.first.get();
284  MDNode *OldInlinedAt = Entry.second.get();
285  assert(OldScope && OldInlinedAt &&
286         "Entry should be non-canonical if either val dropped to null");
287
288  // Otherwise, we do have an entry in it, nuke it and we're done.
289  assert(Ctx->ScopeInlinedAtIdx[std::make_pair(OldScope, OldInlinedAt)] == Idx&&
290         "Mapping out of date");
291  Ctx->ScopeInlinedAtIdx.erase(std::make_pair(OldScope, OldInlinedAt));
292
293  // Reset this VH to null.  Drop both 'Idx' values to null to indicate that
294  // we're in non-canonical form now.
295  setValPtr(nullptr);
296  Entry.first.Idx = Entry.second.Idx = 0;
297}
298
299void DebugRecVH::allUsesReplacedWith(Value *NewVa) {
300  // If being replaced with a non-mdnode value (e.g. undef) handle this as if
301  // the mdnode got deleted.
302  MDNode *NewVal = dyn_cast<MDNode>(NewVa);
303  if (!NewVal) return deleted();
304
305  // If this is a non-canonical reference, just change it, we know it already
306  // doesn't have a map entry.
307  if (Idx == 0) {
308    setValPtr(NewVa);
309    return;
310  }
311
312  MDNode *OldVal = get();
313  assert(OldVal != NewVa && "Node replaced with self?");
314
315  // If the index is positive, it is an entry in ScopeRecords.
316  if (Idx > 0) {
317    assert(Ctx->ScopeRecordIdx[OldVal] == Idx && "Mapping out of date!");
318    Ctx->ScopeRecordIdx.erase(OldVal);
319    setValPtr(NewVal);
320
321    int NewEntry = Ctx->getOrAddScopeRecordIdxEntry(NewVal, Idx);
322
323    // If NewVal already has an entry, this becomes a non-canonical reference,
324    // just drop Idx to 0 to signify this.
325    if (NewEntry != Idx)
326      Idx = 0;
327    return;
328  }
329
330  // Otherwise, it is an entry in ScopeInlinedAtRecords, we don't know if it
331  // is the scope or the inlined-at record entry.
332  assert(unsigned(-Idx-1) < Ctx->ScopeInlinedAtRecords.size());
333  std::pair<DebugRecVH, DebugRecVH> &Entry = Ctx->ScopeInlinedAtRecords[-Idx-1];
334  assert((this == &Entry.first || this == &Entry.second) &&
335         "Mapping out of date!");
336
337  MDNode *OldScope = Entry.first.get();
338  MDNode *OldInlinedAt = Entry.second.get();
339  assert(OldScope && OldInlinedAt &&
340         "Entry should be non-canonical if either val dropped to null");
341
342  // Otherwise, we do have an entry in it, nuke it and we're done.
343  assert(Ctx->ScopeInlinedAtIdx[std::make_pair(OldScope, OldInlinedAt)] == Idx&&
344         "Mapping out of date");
345  Ctx->ScopeInlinedAtIdx.erase(std::make_pair(OldScope, OldInlinedAt));
346
347  // Reset this VH to the new value.
348  setValPtr(NewVal);
349
350  int NewIdx = Ctx->getOrAddScopeInlinedAtIdxEntry(Entry.first.get(),
351                                                   Entry.second.get(), Idx);
352  // If NewVal already has an entry, this becomes a non-canonical reference,
353  // just drop Idx to 0 to signify this.
354  if (NewIdx != Idx) {
355    std::pair<DebugRecVH, DebugRecVH> &Entry=Ctx->ScopeInlinedAtRecords[-Idx-1];
356    Entry.first.Idx = Entry.second.Idx = 0;
357  }
358}
359