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/Support/DebugLoc.h"
11#include "llvm/DebugInfo.h"
12#include "llvm/ADT/DenseMapInfo.h"
13#include "LLVMContextImpl.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
73
74DebugLoc DebugLoc::get(unsigned Line, unsigned Col,
75                       MDNode *Scope, MDNode *InlinedAt) {
76  DebugLoc Result;
77
78  // If no scope is available, this is an unknown location.
79  if (Scope == 0) return Result;
80
81  // Saturate line and col to "unknown".
82  if (Col > 255) Col = 0;
83  if (Line >= (1 << 24)) Line = 0;
84  Result.LineCol = Line | (Col << 24);
85
86  LLVMContext &Ctx = Scope->getContext();
87
88  // If there is no inlined-at location, use the ScopeRecords array.
89  if (InlinedAt == 0)
90    Result.ScopeIdx = Ctx.pImpl->getOrAddScopeRecordIdxEntry(Scope, 0);
91  else
92    Result.ScopeIdx = Ctx.pImpl->getOrAddScopeInlinedAtIdxEntry(Scope,
93                                                                InlinedAt, 0);
94
95  return Result;
96}
97
98/// getAsMDNode - This method converts the compressed DebugLoc node into a
99/// DILocation compatible MDNode.
100MDNode *DebugLoc::getAsMDNode(const LLVMContext &Ctx) const {
101  if (isUnknown()) return 0;
102
103  MDNode *Scope, *IA;
104  getScopeAndInlinedAt(Scope, IA, Ctx);
105  assert(Scope && "If scope is null, this should be isUnknown()");
106
107  LLVMContext &Ctx2 = Scope->getContext();
108  Type *Int32 = Type::getInt32Ty(Ctx2);
109  Value *Elts[] = {
110    ConstantInt::get(Int32, getLine()), ConstantInt::get(Int32, getCol()),
111    Scope, IA
112  };
113  return MDNode::get(Ctx2, Elts);
114}
115
116/// getFromDILocation - Translate the DILocation quad into a DebugLoc.
117DebugLoc DebugLoc::getFromDILocation(MDNode *N) {
118  DILocation Loc(N);
119  MDNode *Scope = Loc.getScope();
120  if (Scope == 0) return DebugLoc();
121  return get(Loc.getLineNumber(), Loc.getColumnNumber(), Scope,
122             Loc.getOrigLocation());
123}
124
125/// getFromDILexicalBlock - Translate the DILexicalBlock into a DebugLoc.
126DebugLoc DebugLoc::getFromDILexicalBlock(MDNode *N) {
127  DILexicalBlock LexBlock(N);
128  MDNode *Scope = LexBlock.getContext();
129  if (Scope == 0) return DebugLoc();
130  return get(LexBlock.getLineNumber(), LexBlock.getColumnNumber(), Scope, NULL);
131}
132
133void DebugLoc::dump(const LLVMContext &Ctx) const {
134#ifndef NDEBUG
135  if (!isUnknown()) {
136    dbgs() << getLine();
137    if (getCol() != 0)
138      dbgs() << ',' << getCol();
139    DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(getInlinedAt(Ctx));
140    if (!InlinedAtDL.isUnknown()) {
141      dbgs() << " @ ";
142      InlinedAtDL.dump(Ctx);
143    } else
144      dbgs() << "\n";
145  }
146#endif
147}
148
149//===----------------------------------------------------------------------===//
150// DenseMap specialization
151//===----------------------------------------------------------------------===//
152
153unsigned DenseMapInfo<DebugLoc>::getHashValue(const DebugLoc &Key) {
154  return static_cast<unsigned>(hash_combine(Key.LineCol, Key.ScopeIdx));
155}
156
157//===----------------------------------------------------------------------===//
158// LLVMContextImpl Implementation
159//===----------------------------------------------------------------------===//
160
161int LLVMContextImpl::getOrAddScopeRecordIdxEntry(MDNode *Scope,
162                                                 int ExistingIdx) {
163  // If we already have an entry for this scope, return it.
164  int &Idx = ScopeRecordIdx[Scope];
165  if (Idx) return Idx;
166
167  // If we don't have an entry, but ExistingIdx is specified, use it.
168  if (ExistingIdx)
169    return Idx = ExistingIdx;
170
171  // Otherwise add a new entry.
172
173  // Start out ScopeRecords with a minimal reasonable size to avoid
174  // excessive reallocation starting out.
175  if (ScopeRecords.empty())
176    ScopeRecords.reserve(128);
177
178  // Index is biased by 1 for index.
179  Idx = ScopeRecords.size()+1;
180  ScopeRecords.push_back(DebugRecVH(Scope, this, Idx));
181  return Idx;
182}
183
184int LLVMContextImpl::getOrAddScopeInlinedAtIdxEntry(MDNode *Scope, MDNode *IA,
185                                                    int ExistingIdx) {
186  // If we already have an entry, return it.
187  int &Idx = ScopeInlinedAtIdx[std::make_pair(Scope, IA)];
188  if (Idx) return Idx;
189
190  // If we don't have an entry, but ExistingIdx is specified, use it.
191  if (ExistingIdx)
192    return Idx = ExistingIdx;
193
194  // Start out ScopeInlinedAtRecords with a minimal reasonable size to avoid
195  // excessive reallocation starting out.
196  if (ScopeInlinedAtRecords.empty())
197    ScopeInlinedAtRecords.reserve(128);
198
199  // Index is biased by 1 and negated.
200  Idx = -ScopeInlinedAtRecords.size()-1;
201  ScopeInlinedAtRecords.push_back(std::make_pair(DebugRecVH(Scope, this, Idx),
202                                                 DebugRecVH(IA, this, Idx)));
203  return Idx;
204}
205
206
207//===----------------------------------------------------------------------===//
208// DebugRecVH Implementation
209//===----------------------------------------------------------------------===//
210
211/// deleted - The MDNode this is pointing to got deleted, so this pointer needs
212/// to drop to null and we need remove our entry from the DenseMap.
213void DebugRecVH::deleted() {
214  // If this is a non-canonical reference, just drop the value to null, we know
215  // it doesn't have a map entry.
216  if (Idx == 0) {
217    setValPtr(0);
218    return;
219  }
220
221  MDNode *Cur = get();
222
223  // If the index is positive, it is an entry in ScopeRecords.
224  if (Idx > 0) {
225    assert(Ctx->ScopeRecordIdx[Cur] == Idx && "Mapping out of date!");
226    Ctx->ScopeRecordIdx.erase(Cur);
227    // Reset this VH to null and we're done.
228    setValPtr(0);
229    Idx = 0;
230    return;
231  }
232
233  // Otherwise, it is an entry in ScopeInlinedAtRecords, we don't know if it
234  // is the scope or the inlined-at record entry.
235  assert(unsigned(-Idx-1) < Ctx->ScopeInlinedAtRecords.size());
236  std::pair<DebugRecVH, DebugRecVH> &Entry = Ctx->ScopeInlinedAtRecords[-Idx-1];
237  assert((this == &Entry.first || this == &Entry.second) &&
238         "Mapping out of date!");
239
240  MDNode *OldScope = Entry.first.get();
241  MDNode *OldInlinedAt = Entry.second.get();
242  assert(OldScope != 0 && OldInlinedAt != 0 &&
243         "Entry should be non-canonical if either val dropped to null");
244
245  // Otherwise, we do have an entry in it, nuke it and we're done.
246  assert(Ctx->ScopeInlinedAtIdx[std::make_pair(OldScope, OldInlinedAt)] == Idx&&
247         "Mapping out of date");
248  Ctx->ScopeInlinedAtIdx.erase(std::make_pair(OldScope, OldInlinedAt));
249
250  // Reset this VH to null.  Drop both 'Idx' values to null to indicate that
251  // we're in non-canonical form now.
252  setValPtr(0);
253  Entry.first.Idx = Entry.second.Idx = 0;
254}
255
256void DebugRecVH::allUsesReplacedWith(Value *NewVa) {
257  // If being replaced with a non-mdnode value (e.g. undef) handle this as if
258  // the mdnode got deleted.
259  MDNode *NewVal = dyn_cast<MDNode>(NewVa);
260  if (NewVal == 0) return deleted();
261
262  // If this is a non-canonical reference, just change it, we know it already
263  // doesn't have a map entry.
264  if (Idx == 0) {
265    setValPtr(NewVa);
266    return;
267  }
268
269  MDNode *OldVal = get();
270  assert(OldVal != NewVa && "Node replaced with self?");
271
272  // If the index is positive, it is an entry in ScopeRecords.
273  if (Idx > 0) {
274    assert(Ctx->ScopeRecordIdx[OldVal] == Idx && "Mapping out of date!");
275    Ctx->ScopeRecordIdx.erase(OldVal);
276    setValPtr(NewVal);
277
278    int NewEntry = Ctx->getOrAddScopeRecordIdxEntry(NewVal, Idx);
279
280    // If NewVal already has an entry, this becomes a non-canonical reference,
281    // just drop Idx to 0 to signify this.
282    if (NewEntry != Idx)
283      Idx = 0;
284    return;
285  }
286
287  // Otherwise, it is an entry in ScopeInlinedAtRecords, we don't know if it
288  // is the scope or the inlined-at record entry.
289  assert(unsigned(-Idx-1) < Ctx->ScopeInlinedAtRecords.size());
290  std::pair<DebugRecVH, DebugRecVH> &Entry = Ctx->ScopeInlinedAtRecords[-Idx-1];
291  assert((this == &Entry.first || this == &Entry.second) &&
292         "Mapping out of date!");
293
294  MDNode *OldScope = Entry.first.get();
295  MDNode *OldInlinedAt = Entry.second.get();
296  assert(OldScope != 0 && OldInlinedAt != 0 &&
297         "Entry should be non-canonical if either val dropped to null");
298
299  // Otherwise, we do have an entry in it, nuke it and we're done.
300  assert(Ctx->ScopeInlinedAtIdx[std::make_pair(OldScope, OldInlinedAt)] == Idx&&
301         "Mapping out of date");
302  Ctx->ScopeInlinedAtIdx.erase(std::make_pair(OldScope, OldInlinedAt));
303
304  // Reset this VH to the new value.
305  setValPtr(NewVal);
306
307  int NewIdx = Ctx->getOrAddScopeInlinedAtIdxEntry(Entry.first.get(),
308                                                   Entry.second.get(), Idx);
309  // If NewVal already has an entry, this becomes a non-canonical reference,
310  // just drop Idx to 0 to signify this.
311  if (NewIdx != Idx) {
312    std::pair<DebugRecVH, DebugRecVH> &Entry=Ctx->ScopeInlinedAtRecords[-Idx-1];
313    Entry.first.Idx = Entry.second.Idx = 0;
314  }
315}
316