3 files changed, 27 insertions, 45 deletions

diff --git a/lld/ELF/GdbIndex.cpp b/lld/ELF/GdbIndex.cpp
index 4a79aee8981..592a9acada5 100644
--- a/lld/ELF/GdbIndex.cpp
+++ b/lld/ELF/GdbIndex.cpp
@@ -59,6 +59,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "GdbIndex.h"
+#include "Memory.h"
 #include "llvm/DebugInfo/DWARF/DWARFDebugPubTable.h"
 #include "llvm/Object/ELFObjectFile.h"
 
@@ -106,48 +107,32 @@ GdbIndexBuilder<ELFT>::readPubNamesAndTypes() {
 }
 
 std::pair<bool, GdbSymbol *> GdbHashTab::add(uint32_t Hash, size_t Offset) {
-  if (Size * 4 / 3 >= Table.size())
-    expand();
-
-  GdbSymbol **Slot = findSlot(Hash, Offset);
-  bool New = false;
-  if (*Slot == nullptr) {
-    ++Size;
-    *Slot = new (Alloc) GdbSymbol(Hash, Offset);
-    New = true;
-  }
-  return {New, *Slot};
+  GdbSymbol *&Sym = Map[{Hash, Offset}];
+  if (Sym)
+    return {false, Sym};
+  ++Size;
+  Sym = make<GdbSymbol>(Hash, Offset);
+  return {true, Sym};
 }
 
-void GdbHashTab::expand() {
-  if (Table.empty()) {
-    Table.resize(InitialSize);
-    return;
-  }
-  std::vector<GdbSymbol *> NewTable(Table.size() * 2);
-  NewTable.swap(Table);
-
-  for (GdbSymbol *Sym : NewTable) {
-    if (!Sym)
-      continue;
-    GdbSymbol **Slot = findSlot(Sym->NameHash, Sym->NameOffset);
-    *Slot = Sym;
-  }
-}
+void GdbHashTab::finalizeContents() {
+  Table.resize(std::max(1024UL, NextPowerOf2(Map.size() * 4 / 3)));
+
+  for (auto &P : Map) {
+    GdbSymbol *Sym = P.second;
+
+    uint32_t I = Sym->NameHash & (Table.size() - 1);
+    uint32_t Step = ((Sym->NameHash * 17) & (Table.size() - 1)) | 1;
+
+    for (;;) {
+      if (Table[I]) {
+        I = (I + Step) & (Table.size() - 1);
+        continue;
+      }
 
-// Methods finds a slot for symbol with given hash. The step size used to find
-// the next candidate slot when handling a hash collision is specified in
-// .gdb_index section format. The hash value for a table entry is computed by
-// applying an iterative hash function to the symbol's name.
-GdbSymbol **GdbHashTab::findSlot(uint32_t Hash, size_t Offset) {
-  uint32_t Index = Hash & (Table.size() - 1);
-  uint32_t Step = ((Hash * 17) & (Table.size() - 1)) | 1;
-
-  for (;;) {
-    GdbSymbol *S = Table[Index];
-    if (!S || ((S->NameOffset == Offset) && (S->NameHash == Hash)))
-      return &Table[Index];
-    Index = (Index + Step) & (Table.size() - 1);
+      Table[I] = Sym;
+      break;
+    }
   }
 }
 
diff --git a/lld/ELF/GdbIndex.h b/lld/ELF/GdbIndex.h
index e0b3fd167dc..eec573099ef 100644
--- a/lld/ELF/GdbIndex.h
+++ b/lld/ELF/GdbIndex.h
@@ -75,22 +75,18 @@ class GdbHashTab final {
 public:
   std::pair<bool, GdbSymbol *> add(uint32_t Hash, size_t Offset);
 
+  void finalizeContents();
   size_t getCapacity() { return Table.size(); }
   GdbSymbol *getSymbol(size_t I) { return Table[I]; }
 
 private:
-  void expand();
-
   GdbSymbol **findSlot(uint32_t Hash, size_t Offset);
 
-  llvm::BumpPtrAllocator Alloc;
+  llvm::DenseMap<std::pair<uint32_t, size_t>, GdbSymbol *> Map;
   std::vector<GdbSymbol *> Table;
 
   // Size keeps the amount of filled entries in Table.
   size_t Size = 0;
-
-  // Initial size must be a power of 2.
-  static const int32_t InitialSize = 1024;
 };
 
 } // namespace elf
diff --git a/lld/ELF/SyntheticSections.cpp b/lld/ELF/SyntheticSections.cpp
index 97d6a7ce982..e9516759458 100644
--- a/lld/ELF/SyntheticSections.cpp
+++ b/lld/ELF/SyntheticSections.cpp
@@ -1749,6 +1749,7 @@ template <class ELFT> void GdbIndexSection<ELFT>::finalizeContents() {
   Finalized = true;
 
   parseDebugSections();
+  SymbolTable.finalizeContents();
 
   // GdbIndex header consist from version fields
   // and 5 more fields with different kinds of offsets.