Use owning pointers instead of raw pointers for Atom's to fix leaks.

Currently each File contains an BumpPtrAllocator in which Atom's are
allocated.  Some Atom's contain data structures like std::vector which
leak as we don't run ~Atom when they are BumpPtrAllocate'd.

Now each File actually owns its Atom's using an OwningAtomPtr.  This
is analygous to std::unique_ptr and may be replaced by it if possible.

An Atom can therefore only be owned by a single File, so the Resolver now
moves them from one File to another.  The MachOLinkingContext owns the File's
and so clears all the Atom's in ~MachOLinkingContext, then delete's all the
File's.  This makes sure all Atom's have been destructed before any of the
BumpPtrAllocator's in which they run have gone away.

Should hopefully fix the remaining leaks.  Will keep an eye on the bots to
make sure.

llvm-svn: 264022

1 files changed, 11 insertions, 4 deletions

diff --git a/lld/lib/ReaderWriter/FileArchive.cpp b/lld/lib/ReaderWriter/FileArchive.cpp
index a47024ca4f6..73b86127797 100644
--- a/lld/lib/ReaderWriter/FileArchive.cpp
+++ b/lld/lib/ReaderWriter/FileArchive.cpp
@@ -88,22 +88,29 @@ public:
     return std::error_code();
   }
 
-  const AtomVector<DefinedAtom> &defined() const override {
+  const AtomRange<DefinedAtom> defined() const override {
     return _noDefinedAtoms;
   }
 
-  const AtomVector<UndefinedAtom> &undefined() const override {
+  const AtomRange<UndefinedAtom> undefined() const override {
     return _noUndefinedAtoms;
   }
 
-  const AtomVector<SharedLibraryAtom> &sharedLibrary() const override {
+  const AtomRange<SharedLibraryAtom> sharedLibrary() const override {
     return _noSharedLibraryAtoms;
   }
 
-  const AtomVector<AbsoluteAtom> &absolute() const override {
+  const AtomRange<AbsoluteAtom> absolute() const override {
     return _noAbsoluteAtoms;
   }
 
+  void clearAtoms() override {
+    _noDefinedAtoms.clear();
+    _noUndefinedAtoms.clear();
+    _noSharedLibraryAtoms.clear();
+    _noAbsoluteAtoms.clear();
+  }
+
 protected:
   std::error_code doParse() override {
     // Make Archive object which will be owned by FileArchive object.