1 files changed, 72 insertions, 41 deletions
diff --git a/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp
index a71f35e..f8cdde2 100644
--- a/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp
+++ b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp
@@ -30,14 +30,14 @@ DwarfAccelTable::DwarfAccelTable(ArrayRef<DwarfAccelTable::Atom> atomList)
     : Header(8 + (atomList.size() * 4)), HeaderData(atomList),
       Entries(Allocator) {}
 
-void DwarfAccelTable::AddName(StringRef Name, MCSymbol *StrSym, const DIE *die,
+void DwarfAccelTable::AddName(DwarfStringPoolEntryRef Name, const DIE *die,
                               char Flags) {
   assert(Data.empty() && "Already finalized!");
   // If the string is in the list already then add this die to the list
   // otherwise add a new one.
-  DataArray &DIEs = Entries[Name];
-  assert(!DIEs.StrSym || DIEs.StrSym == StrSym);
-  DIEs.StrSym = StrSym;
+  DataArray &DIEs = Entries[Name.getString()];
+  assert(!DIEs.Name || DIEs.Name == Name);
+  DIEs.Name = Name;
   DIEs.Values.push_back(new (Allocator) HashDataContents(die, Flags));
 }
 
@@ -54,7 +54,7 @@ void DwarfAccelTable::ComputeBucketCount(void) {
   // Then compute the bucket size, minimum of 1 bucket.
   if (num > 1024)
     Header.bucket_count = num / 4;
-  if (num > 16)
+  else if (num > 16)
     Header.bucket_count = num / 2;
   else
     Header.bucket_count = num > 0 ? num : 1;
@@ -70,6 +70,7 @@ static bool compareDIEs(const DwarfAccelTable::HashDataContents *A,
 
 void DwarfAccelTable::FinalizeTable(AsmPrinter *Asm, StringRef Prefix) {
   // Create the individual hash data outputs.
+  Data.reserve(Entries.size());
   for (StringMap<DataArray>::iterator EI = Entries.begin(), EE = Entries.end();
        EI != EE; ++EI) {
 
@@ -95,33 +96,42 @@ void DwarfAccelTable::FinalizeTable(AsmPrinter *Asm, StringRef Prefix) {
   for (size_t i = 0, e = Data.size(); i < e; ++i) {
     uint32_t bucket = Data[i]->HashValue % Header.bucket_count;
     Buckets[bucket].push_back(Data[i]);
-    Data[i]->Sym = Asm->GetTempSymbol(Prefix, i);
+    Data[i]->Sym = Asm->createTempSymbol(Prefix);
   }
+
+  // Sort the contents of the buckets by hash value so that hash
+  // collisions end up together. Stable sort makes testing easier and
+  // doesn't cost much more.
+  for (size_t i = 0; i < Buckets.size(); ++i)
+    std::stable_sort(Buckets[i].begin(), Buckets[i].end(),
+                     [] (HashData *LHS, HashData *RHS) {
+                       return LHS->HashValue < RHS->HashValue;
+                     });
 }
 
 // Emits the header for the table via the AsmPrinter.
 void DwarfAccelTable::EmitHeader(AsmPrinter *Asm) {
-  Asm->OutStreamer.AddComment("Header Magic");
+  Asm->OutStreamer->AddComment("Header Magic");
   Asm->EmitInt32(Header.magic);
-  Asm->OutStreamer.AddComment("Header Version");
+  Asm->OutStreamer->AddComment("Header Version");
   Asm->EmitInt16(Header.version);
-  Asm->OutStreamer.AddComment("Header Hash Function");
+  Asm->OutStreamer->AddComment("Header Hash Function");
   Asm->EmitInt16(Header.hash_function);
-  Asm->OutStreamer.AddComment("Header Bucket Count");
+  Asm->OutStreamer->AddComment("Header Bucket Count");
   Asm->EmitInt32(Header.bucket_count);
-  Asm->OutStreamer.AddComment("Header Hash Count");
+  Asm->OutStreamer->AddComment("Header Hash Count");
   Asm->EmitInt32(Header.hashes_count);
-  Asm->OutStreamer.AddComment("Header Data Length");
+  Asm->OutStreamer->AddComment("Header Data Length");
   Asm->EmitInt32(Header.header_data_len);
-  Asm->OutStreamer.AddComment("HeaderData Die Offset Base");
+  Asm->OutStreamer->AddComment("HeaderData Die Offset Base");
   Asm->EmitInt32(HeaderData.die_offset_base);
-  Asm->OutStreamer.AddComment("HeaderData Atom Count");
+  Asm->OutStreamer->AddComment("HeaderData Atom Count");
   Asm->EmitInt32(HeaderData.Atoms.size());
   for (size_t i = 0; i < HeaderData.Atoms.size(); i++) {
     Atom A = HeaderData.Atoms[i];
-    Asm->OutStreamer.AddComment(dwarf::AtomTypeString(A.type));
+    Asm->OutStreamer->AddComment(dwarf::AtomTypeString(A.type));
     Asm->EmitInt16(A.type);
-    Asm->OutStreamer.AddComment(dwarf::FormEncodingString(A.form));
+    Asm->OutStreamer->AddComment(dwarf::FormEncodingString(A.form));
     Asm->EmitInt16(A.form);
   }
 }
@@ -131,24 +141,37 @@ void DwarfAccelTable::EmitHeader(AsmPrinter *Asm) {
 void DwarfAccelTable::EmitBuckets(AsmPrinter *Asm) {
   unsigned index = 0;
   for (size_t i = 0, e = Buckets.size(); i < e; ++i) {
-    Asm->OutStreamer.AddComment("Bucket " + Twine(i));
+    Asm->OutStreamer->AddComment("Bucket " + Twine(i));
     if (Buckets[i].size() != 0)
       Asm->EmitInt32(index);
     else
       Asm->EmitInt32(UINT32_MAX);
-    index += Buckets[i].size();
+    // Buckets point in the list of hashes, not to the data. Do not
+    // increment the index multiple times in case of hash collisions.
+    uint64_t PrevHash = UINT64_MAX;
+    for (auto *HD : Buckets[i]) {
+      uint32_t HashValue = HD->HashValue;
+      if (PrevHash != HashValue)
+        ++index;
+      PrevHash = HashValue;
+    }
   }
 }
 
 // Walk through the buckets and emit the individual hashes for each
 // bucket.
 void DwarfAccelTable::EmitHashes(AsmPrinter *Asm) {
+  uint64_t PrevHash = UINT64_MAX;
   for (size_t i = 0, e = Buckets.size(); i < e; ++i) {
     for (HashList::const_iterator HI = Buckets[i].begin(),
                                   HE = Buckets[i].end();
          HI != HE; ++HI) {
-      Asm->OutStreamer.AddComment("Hash in Bucket " + Twine(i));
-      Asm->EmitInt32((*HI)->HashValue);
+      uint32_t HashValue = (*HI)->HashValue;
+      if (PrevHash == HashValue)
+        continue;
+      Asm->OutStreamer->AddComment("Hash in Bucket " + Twine(i));
+      Asm->EmitInt32(HashValue);
+      PrevHash = HashValue;
     }
   }
 }
@@ -157,17 +180,22 @@ void DwarfAccelTable::EmitHashes(AsmPrinter *Asm) {
 // element in each bucket. This is done via a symbol subtraction from the
 // beginning of the section. The non-section symbol will be output later
 // when we emit the actual data.
-void DwarfAccelTable::EmitOffsets(AsmPrinter *Asm, MCSymbol *SecBegin) {
+void DwarfAccelTable::emitOffsets(AsmPrinter *Asm, const MCSymbol *SecBegin) {
+  uint64_t PrevHash = UINT64_MAX;
   for (size_t i = 0, e = Buckets.size(); i < e; ++i) {
     for (HashList::const_iterator HI = Buckets[i].begin(),
                                   HE = Buckets[i].end();
          HI != HE; ++HI) {
-      Asm->OutStreamer.AddComment("Offset in Bucket " + Twine(i));
-      MCContext &Context = Asm->OutStreamer.getContext();
-      const MCExpr *Sub = MCBinaryExpr::CreateSub(
-          MCSymbolRefExpr::Create((*HI)->Sym, Context),
-          MCSymbolRefExpr::Create(SecBegin, Context), Context);
-      Asm->OutStreamer.EmitValue(Sub, sizeof(uint32_t));
+      uint32_t HashValue = (*HI)->HashValue;
+      if (PrevHash == HashValue)
+        continue;
+      PrevHash = HashValue;
+      Asm->OutStreamer->AddComment("Offset in Bucket " + Twine(i));
+      MCContext &Context = Asm->OutStreamer->getContext();
+      const MCExpr *Sub = MCBinaryExpr::createSub(
+          MCSymbolRefExpr::create((*HI)->Sym, Context),
+          MCSymbolRefExpr::create(SecBegin, Context), Context);
+      Asm->OutStreamer->EmitValue(Sub, sizeof(uint32_t));
     }
   }
 }
@@ -175,18 +203,21 @@ void DwarfAccelTable::EmitOffsets(AsmPrinter *Asm, MCSymbol *SecBegin) {
 // Walk through the buckets and emit the full data for each element in
 // the bucket. For the string case emit the dies and the various offsets.
 // Terminate each HashData bucket with 0.
-void DwarfAccelTable::EmitData(AsmPrinter *Asm, DwarfDebug *D,
-                               MCSymbol *StrSym) {
-  uint64_t PrevHash = UINT64_MAX;
+void DwarfAccelTable::EmitData(AsmPrinter *Asm, DwarfDebug *D) {
   for (size_t i = 0, e = Buckets.size(); i < e; ++i) {
+    uint64_t PrevHash = UINT64_MAX;
     for (HashList::const_iterator HI = Buckets[i].begin(),
                                   HE = Buckets[i].end();
          HI != HE; ++HI) {
+      // Terminate the previous entry if there is no hash collision
+      // with the current one.
+      if (PrevHash != UINT64_MAX && PrevHash != (*HI)->HashValue)
+        Asm->EmitInt32(0);
       // Remember to emit the label for our offset.
-      Asm->OutStreamer.EmitLabel((*HI)->Sym);
-      Asm->OutStreamer.AddComment((*HI)->Str);
-      Asm->EmitSectionOffset((*HI)->Data.StrSym, StrSym);
-      Asm->OutStreamer.AddComment("Num DIEs");
+      Asm->OutStreamer->EmitLabel((*HI)->Sym);
+      Asm->OutStreamer->AddComment((*HI)->Str);
+      Asm->emitDwarfStringOffset((*HI)->Data.Name);
+      Asm->OutStreamer->AddComment("Num DIEs");
       Asm->EmitInt32((*HI)->Data.Values.size());
       for (HashDataContents *HD : (*HI)->Data.Values) {
         // Emit the DIE offset
@@ -200,17 +231,17 @@ void DwarfAccelTable::EmitData(AsmPrinter *Asm, DwarfDebug *D,
           Asm->EmitInt8(HD->Flags);
         }
       }
-      // Emit a 0 to terminate the data unless we have a hash collision.
-      if (PrevHash != (*HI)->HashValue)
-        Asm->EmitInt32(0);
       PrevHash = (*HI)->HashValue;
     }
+    // Emit the final end marker for the bucket.
+    if (!Buckets[i].empty())
+      Asm->EmitInt32(0);
   }
 }
 
 // Emit the entire data structure to the output file.
-void DwarfAccelTable::Emit(AsmPrinter *Asm, MCSymbol *SecBegin, DwarfDebug *D,
-                           MCSymbol *StrSym) {
+void DwarfAccelTable::emit(AsmPrinter *Asm, const MCSymbol *SecBegin,
+                           DwarfDebug *D) {
   // Emit the header.
   EmitHeader(Asm);
 
@@ -221,10 +252,10 @@ void DwarfAccelTable::Emit(AsmPrinter *Asm, MCSymbol *SecBegin, DwarfDebug *D,
   EmitHashes(Asm);
 
   // Emit the offsets.
-  EmitOffsets(Asm, SecBegin);
+  emitOffsets(Asm, SecBegin);
 
   // Emit the hash data.
-  EmitData(Asm, D, StrSym);
+  EmitData(Asm, D);
 }
 
 #ifndef NDEBUG