Replace SharedSymbols with Defined when creating copy relocations.

This is slightly simpler to read IMHO. Now if a symbol has a position
in the file, it is Defined.

The main motivation is that with this a SharedSymbol doesn't need a
section, which reduces the size of SymbolUnion.

With this the peak allocation when linking chromium goes from 568.1 to
564.2 MB.

llvm-svn: 330966

1 files changed, 14 insertions, 29 deletions

diff --git a/lld/ELF/MapFile.cpp b/lld/ELF/MapFile.cpp
index 4e8e045783e..c5984c9ebc3 100644
--- a/lld/ELF/MapFile.cpp
+++ b/lld/ELF/MapFile.cpp
@@ -38,7 +38,7 @@ using namespace llvm::object;
 using namespace lld;
 using namespace lld::elf;
 
-typedef DenseMap<const SectionBase *, SmallVector<Symbol *, 4>> SymbolMapTy;
+typedef DenseMap<const SectionBase *, SmallVector<Defined *, 4>> SymbolMapTy;
 
 static const std::string Indent8 = "        ";          // 8 spaces
 static const std::string Indent16 = "                "; // 16 spaces
@@ -53,44 +53,29 @@ static void writeHeader(raw_ostream &OS, uint64_t VMA, uint64_t LMA,
 }
 
 // Returns a list of all symbols that we want to print out.
-static std::vector<Symbol *> getSymbols() {
-  std::vector<Symbol *> V;
-  for (InputFile *File : ObjectFiles) {
-    for (Symbol *B : File->getSymbols()) {
-      if (auto *SS = dyn_cast<SharedSymbol>(B))
-        if (SS->CopyRelSec || SS->NeedsPltAddr)
-          V.push_back(SS);
+static std::vector<Defined *> getSymbols() {
+  std::vector<Defined *> V;
+  for (InputFile *File : ObjectFiles)
+    for (Symbol *B : File->getSymbols())
       if (auto *DR = dyn_cast<Defined>(B))
-        if (DR->File == File && !DR->isSection() && DR->Section &&
-            DR->Section->Live)
+        if (!DR->isSection() && DR->Section && DR->Section->Live &&
+            (DR->File == File || DR->NeedsPltAddr || DR->Section->Bss))
           V.push_back(DR);
-    }
-  }
   return V;
 }
 
 // Returns a map from sections to their symbols.
-static SymbolMapTy getSectionSyms(ArrayRef<Symbol *> Syms) {
+static SymbolMapTy getSectionSyms(ArrayRef<Defined *> Syms) {
   SymbolMapTy Ret;
-  for (Symbol *S : Syms) {
-    if (auto *DR = dyn_cast<Defined>(S)) {
-      Ret[DR->Section].push_back(S);
-      continue;
-    }
-
-    SharedSymbol *SS = cast<SharedSymbol>(S);
-    if (SS->CopyRelSec)
-      Ret[SS->CopyRelSec].push_back(S);
-    else
-      Ret[InX::Plt].push_back(S);
-  }
+  for (Defined *DR : Syms)
+    Ret[DR->Section].push_back(DR);
 
   // Sort symbols by address. We want to print out symbols in the
   // order in the output file rather than the order they appeared
   // in the input files.
   for (auto &It : Ret) {
-    SmallVectorImpl<Symbol *> &V = It.second;
-    std::stable_sort(V.begin(), V.end(), [](Symbol *A, Symbol *B) {
+    SmallVectorImpl<Defined *> &V = It.second;
+    std::stable_sort(V.begin(), V.end(), [](Defined *A, Defined *B) {
       return A->getVA() < B->getVA();
     });
   }
@@ -101,7 +86,7 @@ static SymbolMapTy getSectionSyms(ArrayRef<Symbol *> Syms) {
 // Demangling symbols (which is what toString() does) is slow, so
 // we do that in batch using parallel-for.
 static DenseMap<Symbol *, std::string>
-getSymbolStrings(ArrayRef<Symbol *> Syms) {
+getSymbolStrings(ArrayRef<Defined *> Syms) {
   std::vector<std::string> Str(Syms.size());
   parallelForEachN(0, Syms.size(), [&](size_t I) {
     raw_string_ostream OS(Str[I]);
@@ -169,7 +154,7 @@ void elf::writeMapFile() {
   }
 
   // Collect symbol info that we want to print out.
-  std::vector<Symbol *> Syms = getSymbols();
+  std::vector<Defined *> Syms = getSymbols();
   SymbolMapTy SectionSyms = getSectionSyms(Syms);
   DenseMap<Symbol *, std::string> SymStr = getSymbolStrings(Syms);