lib/VMCore/DebugLoc.cpp

   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 "LLVMContextImpl.h"
  12 using namespace llvm;
  13
  14 //===----------------------------------------------------------------------===//
  15 // DebugLoc Implementation
  16 //===----------------------------------------------------------------------===//
  17
  18 MDNode *DebugLoc::getScope(const LLVMContext &Ctx) const {
  19   if (ScopeIdx == 0) return 0;
  20
  21   if (ScopeIdx > 0) {
  22     // Positive ScopeIdx is an index into ScopeRecords, which has no inlined-at
  23     // position specified.
  24     assert(unsigned(ScopeIdx) <= Ctx.pImpl->ScopeRecords.size() &&
  25            "Invalid ScopeIdx!");
  26     return Ctx.pImpl->ScopeRecords[ScopeIdx-1].get();
  27   }
  28
  29   // Otherwise, the index is in the ScopeInlinedAtRecords array.
  30   assert(unsigned(-ScopeIdx) <= Ctx.pImpl->ScopeInlinedAtRecords.size() &&
  31          "Invalid ScopeIdx");
  32   return Ctx.pImpl->ScopeInlinedAtRecords[-ScopeIdx-1].first.get();
  33 }
  34
  35 MDNode *DebugLoc::getInlinedAt(const LLVMContext &Ctx) const {
  36   // Positive ScopeIdx is an index into ScopeRecords, which has no inlined-at
  37   // position specified.  Zero is invalid.
  38   if (ScopeIdx >= 0) return 0;
  39
  40   // Otherwise, the index is in the ScopeInlinedAtRecords array.
  41   assert(unsigned(-ScopeIdx) <= Ctx.pImpl->ScopeInlinedAtRecords.size() &&
  42          "Invalid ScopeIdx");
  43   return Ctx.pImpl->ScopeInlinedAtRecords[-ScopeIdx-1].second.get();
  44 }
  45
  46 /// Return both the Scope and the InlinedAt values.
  47 void DebugLoc::getScopeAndInlinedAt(MDNode *&Scope, MDNode *&IA,
  48                                     const LLVMContext &Ctx) const {
  49   if (ScopeIdx == 0) {
  50     Scope = IA = 0;
  51     return;
  52   }
  53
  54   if (ScopeIdx > 0) {
  55     // Positive ScopeIdx is an index into ScopeRecords, which has no inlined-at
  56     // position specified.
  57     assert(unsigned(ScopeIdx) <= Ctx.pImpl->ScopeRecords.size() &&
  58            "Invalid ScopeIdx!");
  59     Scope = Ctx.pImpl->ScopeRecords[ScopeIdx-1].get();
  60     IA = 0;
  61     return;
  62   }
  63
  64   // Otherwise, the index is in the ScopeInlinedAtRecords array.
  65   assert(unsigned(-ScopeIdx) <= Ctx.pImpl->ScopeInlinedAtRecords.size() &&
  66          "Invalid ScopeIdx");
  67   Scope = Ctx.pImpl->ScopeInlinedAtRecords[-ScopeIdx-1].first.get();
  68   IA    = Ctx.pImpl->ScopeInlinedAtRecords[-ScopeIdx-1].second.get();
  69 }
  70
  71
  72 DebugLoc DebugLoc::get(unsigned Line, unsigned Col,
  73                        MDNode *Scope, MDNode *InlinedAt) {
  74   DebugLoc Result;
  75
  76   // If no scope is available, this is an unknown location.
  77   if (Scope == 0) return Result;
  78
  79   // Saturate line and col to "unknown".
  80   if (Col > 255) Col = 0;
  81   if (Line >= (1 << 24)) Line = 0;
  82   Result.LineCol = Line | (Col << 24);
  83
  84   LLVMContext &Ctx = Scope->getContext();
  85
  86   // If there is no inlined-at location, use the ScopeRecords array.
  87   if (InlinedAt == 0)
  88     Result.ScopeIdx = Ctx.pImpl->getOrAddScopeRecordIdxEntry(Scope, 0);
  89   else
  90     Result.ScopeIdx = Ctx.pImpl->getOrAddScopeInlinedAtIdxEntry(Scope,
  91                                                                 InlinedAt, 0);
  92
  93   return Result;
  94 }
  95
  96 /// getAsMDNode - This method converts the compressed DebugLoc node into a
  97 /// DILocation compatible MDNode.
  98 MDNode *DebugLoc::getAsMDNode(const LLVMContext &Ctx) const {
  99   if (isUnknown()) return 0;
 100
 101   MDNode *Scope, *IA;
 102   getScopeAndInlinedAt(Scope, IA, Ctx);
 103   assert(Scope && "If scope is null, this should be isUnknown()");
 104
 105   LLVMContext &Ctx2 = Scope->getContext();
 106   const Type *Int32 = Type::getInt32Ty(Ctx2);
 107   Value *Elts[] = {
 108     ConstantInt::get(Int32, getLine()), ConstantInt::get(Int32, getCol()),
 109     Scope, IA
 110   };
 111   return MDNode::get(Ctx2, &Elts[0], 4);
 112 }
 113
 114 /// getFromDILocation - Translate the DILocation quad into a DebugLoc.
 115 DebugLoc DebugLoc::getFromDILocation(MDNode *N) {
 116   if (N == 0 || N->getNumOperands() != 4) return DebugLoc();
 117
 118   MDNode *Scope = dyn_cast_or_null<MDNode>(N->getOperand(2));
 119   if (Scope == 0) return DebugLoc();
 120
 121   unsigned LineNo = 0, ColNo = 0;
 122   if (ConstantInt *Line = dyn_cast_or_null<ConstantInt>(N->getOperand(0)))
 123     LineNo = Line->getZExtValue();
 124   if (ConstantInt *Col = dyn_cast_or_null<ConstantInt>(N->getOperand(1)))
 125     ColNo = Col->getZExtValue();
 126
 127   return get(LineNo, ColNo, Scope, dyn_cast_or_null<MDNode>(N->getOperand(3)));
 128 }
 129
 130 //===----------------------------------------------------------------------===//
 131 // LLVMContextImpl Implementation
 132 //===----------------------------------------------------------------------===//
 133
 134 int LLVMContextImpl::getOrAddScopeRecordIdxEntry(MDNode *Scope,
 135                                                  int ExistingIdx) {
 136   // If we already have an entry for this scope, return it.
 137   int &Idx = ScopeRecordIdx[Scope];
 138   if (Idx) return Idx;
 139
 140   // If we don't have an entry, but ExistingIdx is specified, use it.
 141   if (ExistingIdx)
 142     return Idx = ExistingIdx;
 143
 144   // Otherwise add a new entry.
 145
 146   // Start out ScopeRecords with a minimal reasonable size to avoid
 147   // excessive reallocation starting out.
 148   if (ScopeRecords.empty())
 149     ScopeRecords.reserve(128);
 150
 151   // Index is biased by 1 for index.
 152   Idx = ScopeRecords.size()+1;
 153   ScopeRecords.push_back(DebugRecVH(Scope, this, Idx));
 154   return Idx;
 155 }
 156
 157 int LLVMContextImpl::getOrAddScopeInlinedAtIdxEntry(MDNode *Scope, MDNode *IA,
 158                                                     int ExistingIdx) {
 159   // If we already have an entry, return it.
 160   int &Idx = ScopeInlinedAtIdx[std::make_pair(Scope, IA)];
 161   if (Idx) return Idx;
 162
 163   // If we don't have an entry, but ExistingIdx is specified, use it.
 164   if (ExistingIdx)
 165     return Idx = ExistingIdx;
 166
 167   // Start out ScopeInlinedAtRecords with a minimal reasonable size to avoid
 168   // excessive reallocation starting out.
 169   if (ScopeInlinedAtRecords.empty())
 170     ScopeInlinedAtRecords.reserve(128);
 171
 172   // Index is biased by 1 and negated.
 173   Idx = -ScopeInlinedAtRecords.size()-1;
 174   ScopeInlinedAtRecords.push_back(std::make_pair(DebugRecVH(Scope, this, Idx),
 175                                                  DebugRecVH(IA, this, Idx)));
 176   return Idx;
 177 }
 178
 179
 180 //===----------------------------------------------------------------------===//
 181 // DebugRecVH Implementation
 182 //===----------------------------------------------------------------------===//
 183
 184 /// deleted - The MDNode this is pointing to got deleted, so this pointer needs
 185 /// to drop to null and we need remove our entry from the DenseMap.
 186 void DebugRecVH::deleted() {
 187   // If this is a  non-canonical reference, just drop the value to null, we know
 188   // it doesn't have a map entry.
 189   if (Idx == 0) {
 190     setValPtr(0);
 191     return;
 192   }
 193
 194   MDNode *Cur = get();
 195
 196   // If the index is positive, it is an entry in ScopeRecords.
 197   if (Idx > 0) {
 198     assert(Ctx->ScopeRecordIdx[Cur] == Idx && "Mapping out of date!");
 199     Ctx->ScopeRecordIdx.erase(Cur);
 200     // Reset this VH to null and we're done.
 201     setValPtr(0);
 202     Idx = 0;
 203     return;
 204   }
 205
 206   // Otherwise, it is an entry in ScopeInlinedAtRecords, we don't know if it
 207   // is the scope or the inlined-at record entry.
 208   assert(unsigned(-Idx-1) < Ctx->ScopeInlinedAtRecords.size());
 209   std::pair<DebugRecVH, DebugRecVH> &Entry = Ctx->ScopeInlinedAtRecords[-Idx-1];
 210   assert((this == &Entry.first || this == &Entry.second) &&
 211          "Mapping out of date!");
 212
 213   MDNode *OldScope = Entry.first.get();
 214   MDNode *OldInlinedAt = Entry.second.get();
 215   assert(OldScope != 0 && OldInlinedAt != 0 &&
 216          "Entry should be non-canonical if either val dropped to null");
 217
 218   // Otherwise, we do have an entry in it, nuke it and we're done.
 219   assert(Ctx->ScopeInlinedAtIdx[std::make_pair(OldScope, OldInlinedAt)] == Idx&&
 220          "Mapping out of date");
 221   Ctx->ScopeInlinedAtIdx.erase(std::make_pair(OldScope, OldInlinedAt));
 222
 223   // Reset this VH to null.  Drop both 'Idx' values to null to indicate that
 224   // we're in non-canonical form now.
 225   setValPtr(0);
 226   Entry.first.Idx = Entry.second.Idx = 0;
 227 }
 228
 229 void DebugRecVH::allUsesReplacedWith(Value *NewVa) {
 230   // If being replaced with a non-mdnode value (e.g. undef) handle this as if
 231   // the mdnode got deleted.
 232   MDNode *NewVal = dyn_cast<MDNode>(NewVa);
 233   if (NewVal == 0) return deleted();
 234
 235   // If this is a non-canonical reference, just change it, we know it already
 236   // doesn't have a map entry.
 237   if (Idx == 0) {
 238     setValPtr(NewVa);
 239     return;
 240   }
 241
 242   MDNode *OldVal = get();
 243   assert(OldVal != NewVa && "Node replaced with self?");
 244
 245   // If the index is positive, it is an entry in ScopeRecords.
 246   if (Idx > 0) {
 247     assert(Ctx->ScopeRecordIdx[OldVal] == Idx && "Mapping out of date!");
 248     Ctx->ScopeRecordIdx.erase(OldVal);
 249     setValPtr(NewVal);
 250
 251     int NewEntry = Ctx->getOrAddScopeRecordIdxEntry(NewVal, Idx);
 252
 253     // If NewVal already has an entry, this becomes a non-canonical reference,
 254     // just drop Idx to 0 to signify this.
 255     if (NewEntry != Idx)
 256       Idx = 0;
 257     return;
 258   }
 259
 260   // Otherwise, it is an entry in ScopeInlinedAtRecords, we don't know if it
 261   // is the scope or the inlined-at record entry.
 262   assert(unsigned(-Idx-1) < Ctx->ScopeInlinedAtRecords.size());
 263   std::pair<DebugRecVH, DebugRecVH> &Entry = Ctx->ScopeInlinedAtRecords[-Idx-1];
 264   assert((this == &Entry.first || this == &Entry.second) &&
 265          "Mapping out of date!");
 266
 267   MDNode *OldScope = Entry.first.get();
 268   MDNode *OldInlinedAt = Entry.second.get();
 269   assert(OldScope != 0 && OldInlinedAt != 0 &&
 270          "Entry should be non-canonical if either val dropped to null");
 271
 272   // Otherwise, we do have an entry in it, nuke it and we're done.
 273   assert(Ctx->ScopeInlinedAtIdx[std::make_pair(OldScope, OldInlinedAt)] == Idx&&
 274          "Mapping out of date");
 275   Ctx->ScopeInlinedAtIdx.erase(std::make_pair(OldScope, OldInlinedAt));
 276
 277   // Reset this VH to the new value.
 278   setValPtr(NewVal);
 279
 280   int NewIdx = Ctx->getOrAddScopeInlinedAtIdxEntry(Entry.first.get(),
 281                                                    Entry.second.get(), Idx);
 282   // If NewVal already has an entry, this becomes a non-canonical reference,
 283   // just drop Idx to 0 to signify this.
 284   if (NewIdx != Idx) {
 285     std::pair<DebugRecVH, DebugRecVH> &Entry=Ctx->ScopeInlinedAtRecords[-Idx-1];
 286     Entry.first.Idx = Entry.second.Idx = 0;
 287   }
 288 }