DebugLoc.cpp revision 36b56886974eae4f9c5ebc96befd3e7bfe5de338 
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 0;
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 0;
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 = 0;
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 = 0;
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) {
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 == 0) 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 == 0)
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 0;
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 == 0) 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 == 0) return DebugLoc();
150  return get(LexBlock.getLineNumber(), LexBlock.getColumnNumber(), Scope, NULL);
151}
152
153void DebugLoc::dump(const LLVMContext &Ctx) const {
154#ifndef NDEBUG
155  if (!isUnknown()) {
156    dbgs() << getLine();
157    if (getCol() != 0)
158      dbgs() << ',' << getCol();
159    DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(getInlinedAt(Ctx));
160    if (!InlinedAtDL.isUnknown()) {
161      dbgs() << " @ ";
162      InlinedAtDL.dump(Ctx);
163    } else
164      dbgs() << "\n";
165  }
166#endif
167}
168
169//===----------------------------------------------------------------------===//
170// DenseMap specialization
171//===----------------------------------------------------------------------===//
172
173unsigned DenseMapInfo<DebugLoc>::getHashValue(const DebugLoc &Key) {
174  return static_cast<unsigned>(hash_combine(Key.LineCol, Key.ScopeIdx));
175}
176
177//===----------------------------------------------------------------------===//
178// LLVMContextImpl Implementation
179//===----------------------------------------------------------------------===//
180
181int LLVMContextImpl::getOrAddScopeRecordIdxEntry(MDNode *Scope,
182                                                 int ExistingIdx) {
183  // If we already have an entry for this scope, return it.
184  int &Idx = ScopeRecordIdx[Scope];
185  if (Idx) return Idx;
186
187  // If we don't have an entry, but ExistingIdx is specified, use it.
188  if (ExistingIdx)
189    return Idx = ExistingIdx;
190
191  // Otherwise add a new entry.
192
193  // Start out ScopeRecords with a minimal reasonable size to avoid
194  // excessive reallocation starting out.
195  if (ScopeRecords.empty())
196    ScopeRecords.reserve(128);
197
198  // Index is biased by 1 for index.
199  Idx = ScopeRecords.size()+1;
200  ScopeRecords.push_back(DebugRecVH(Scope, this, Idx));
201  return Idx;
202}
203
204int LLVMContextImpl::getOrAddScopeInlinedAtIdxEntry(MDNode *Scope, MDNode *IA,
205                                                    int ExistingIdx) {
206  // If we already have an entry, return it.
207  int &Idx = ScopeInlinedAtIdx[std::make_pair(Scope, IA)];
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  // Start out ScopeInlinedAtRecords with a minimal reasonable size to avoid
215  // excessive reallocation starting out.
216  if (ScopeInlinedAtRecords.empty())
217    ScopeInlinedAtRecords.reserve(128);
218
219  // Index is biased by 1 and negated.
220  Idx = -ScopeInlinedAtRecords.size()-1;
221  ScopeInlinedAtRecords.push_back(std::make_pair(DebugRecVH(Scope, this, Idx),
222                                                 DebugRecVH(IA, this, Idx)));
223  return Idx;
224}
225
226
227//===----------------------------------------------------------------------===//
228// DebugRecVH Implementation
229//===----------------------------------------------------------------------===//
230
231/// deleted - The MDNode this is pointing to got deleted, so this pointer needs
232/// to drop to null and we need remove our entry from the DenseMap.
233void DebugRecVH::deleted() {
234  // If this is a non-canonical reference, just drop the value to null, we know
235  // it doesn't have a map entry.
236  if (Idx == 0) {
237    setValPtr(0);
238    return;
239  }
240
241  MDNode *Cur = get();
242
243  // If the index is positive, it is an entry in ScopeRecords.
244  if (Idx > 0) {
245    assert(Ctx->ScopeRecordIdx[Cur] == Idx && "Mapping out of date!");
246    Ctx->ScopeRecordIdx.erase(Cur);
247    // Reset this VH to null and we're done.
248    setValPtr(0);
249    Idx = 0;
250    return;
251  }
252
253  // Otherwise, it is an entry in ScopeInlinedAtRecords, we don't know if it
254  // is the scope or the inlined-at record entry.
255  assert(unsigned(-Idx-1) < Ctx->ScopeInlinedAtRecords.size());
256  std::pair<DebugRecVH, DebugRecVH> &Entry = Ctx->ScopeInlinedAtRecords[-Idx-1];
257  assert((this == &Entry.first || this == &Entry.second) &&
258         "Mapping out of date!");
259
260  MDNode *OldScope = Entry.first.get();
261  MDNode *OldInlinedAt = Entry.second.get();
262  assert(OldScope != 0 && OldInlinedAt != 0 &&
263         "Entry should be non-canonical if either val dropped to null");
264
265  // Otherwise, we do have an entry in it, nuke it and we're done.
266  assert(Ctx->ScopeInlinedAtIdx[std::make_pair(OldScope, OldInlinedAt)] == Idx&&
267         "Mapping out of date");
268  Ctx->ScopeInlinedAtIdx.erase(std::make_pair(OldScope, OldInlinedAt));
269
270  // Reset this VH to null.  Drop both 'Idx' values to null to indicate that
271  // we're in non-canonical form now.
272  setValPtr(0);
273  Entry.first.Idx = Entry.second.Idx = 0;
274}
275
276void DebugRecVH::allUsesReplacedWith(Value *NewVa) {
277  // If being replaced with a non-mdnode value (e.g. undef) handle this as if
278  // the mdnode got deleted.
279  MDNode *NewVal = dyn_cast<MDNode>(NewVa);
280  if (NewVal == 0) return deleted();
281
282  // If this is a non-canonical reference, just change it, we know it already
283  // doesn't have a map entry.
284  if (Idx == 0) {
285    setValPtr(NewVa);
286    return;
287  }
288
289  MDNode *OldVal = get();
290  assert(OldVal != NewVa && "Node replaced with self?");
291
292  // If the index is positive, it is an entry in ScopeRecords.
293  if (Idx > 0) {
294    assert(Ctx->ScopeRecordIdx[OldVal] == Idx && "Mapping out of date!");
295    Ctx->ScopeRecordIdx.erase(OldVal);
296    setValPtr(NewVal);
297
298    int NewEntry = Ctx->getOrAddScopeRecordIdxEntry(NewVal, Idx);
299
300    // If NewVal already has an entry, this becomes a non-canonical reference,
301    // just drop Idx to 0 to signify this.
302    if (NewEntry != Idx)
303      Idx = 0;
304    return;
305  }
306
307  // Otherwise, it is an entry in ScopeInlinedAtRecords, we don't know if it
308  // is the scope or the inlined-at record entry.
309  assert(unsigned(-Idx-1) < Ctx->ScopeInlinedAtRecords.size());
310  std::pair<DebugRecVH, DebugRecVH> &Entry = Ctx->ScopeInlinedAtRecords[-Idx-1];
311  assert((this == &Entry.first || this == &Entry.second) &&
312         "Mapping out of date!");
313
314  MDNode *OldScope = Entry.first.get();
315  MDNode *OldInlinedAt = Entry.second.get();
316  assert(OldScope != 0 && OldInlinedAt != 0 &&
317         "Entry should be non-canonical if either val dropped to null");
318
319  // Otherwise, we do have an entry in it, nuke it and we're done.
320  assert(Ctx->ScopeInlinedAtIdx[std::make_pair(OldScope, OldInlinedAt)] == Idx&&
321         "Mapping out of date");
322  Ctx->ScopeInlinedAtIdx.erase(std::make_pair(OldScope, OldInlinedAt));
323
324  // Reset this VH to the new value.
325  setValPtr(NewVal);
326
327  int NewIdx = Ctx->getOrAddScopeInlinedAtIdxEntry(Entry.first.get(),
328                                                   Entry.second.get(), Idx);
329  // If NewVal already has an entry, this becomes a non-canonical reference,
330  // just drop Idx to 0 to signify this.
331  if (NewIdx != Idx) {
332    std::pair<DebugRecVH, DebugRecVH> &Entry=Ctx->ScopeInlinedAtRecords[-Idx-1];
333    Entry.first.Idx = Entry.second.Idx = 0;
334  }
335}
336