Introduce symbol cache to PDB NativeSession

Instead of creating symbols directly in the findChildren methods of the native
symbol implementations, they will rely on the NativeSession to act as a factory
for these types.  This lets NativeSession cache the NativeRawSymbols in its
new symbol cache and makes that cache the source of unique IDs for the symbols.

Right now, this affects only NativeCompilandSymbols.  There's no external
change yet, so I think the existing tests are still sufficient.  Coming soon
are patches to extend this to built-in types and enums.

llvm-svn: 306610

1 files changed, 19 insertions, 2 deletions

diff --git a/llvm/lib/DebugInfo/PDB/Native/NativeSession.cpp b/llvm/lib/DebugInfo/PDB/Native/NativeSession.cpp
index 3ab381e76e6..93d43d9ef34 100644
--- a/llvm/lib/DebugInfo/PDB/Native/NativeSession.cpp
+++ b/llvm/lib/DebugInfo/PDB/Native/NativeSession.cpp
@@ -13,6 +13,7 @@
 #include "llvm/DebugInfo/PDB/GenericError.h"
 #include "llvm/DebugInfo/PDB/IPDBEnumChildren.h"
 #include "llvm/DebugInfo/PDB/IPDBSourceFile.h"
+#include "llvm/DebugInfo/PDB/Native/NativeCompilandSymbol.h"
 #include "llvm/DebugInfo/PDB/Native/NativeExeSymbol.h"
 #include "llvm/DebugInfo/PDB/Native/PDBFile.h"
 #include "llvm/DebugInfo/PDB/Native/RawError.h"
@@ -23,8 +24,10 @@
 #include "llvm/Support/Error.h"
 #include "llvm/Support/ErrorOr.h"
 #include "llvm/Support/MemoryBuffer.h"
+
 #include <algorithm>
 #include <memory>
+#include <utility>
 
 using namespace llvm;
 using namespace llvm::msf;
@@ -66,12 +69,23 @@ Error NativeSession::createFromExe(StringRef Path,
   return make_error<RawError>(raw_error_code::feature_unsupported);
 }
 
+std::unique_ptr<PDBSymbolCompiland>
+NativeSession::createCompilandSymbol(DbiModuleDescriptor MI) {
+  const auto Id = static_cast<uint32_t>(SymbolCache.size());
+  SymbolCache.push_back(
+      llvm::make_unique<NativeCompilandSymbol>(*this, Id, MI));
+  return llvm::make_unique<PDBSymbolCompiland>(
+      *this, std::unique_ptr<IPDBRawSymbol>(SymbolCache[Id]->clone()));
+}
+
 uint64_t NativeSession::getLoadAddress() const { return 0; }
 
 void NativeSession::setLoadAddress(uint64_t Address) {}
 
 std::unique_ptr<PDBSymbolExe> NativeSession::getGlobalScope() {
-  auto RawSymbol = llvm::make_unique<NativeExeSymbol>(*this, 0);
+  const auto Id = static_cast<uint32_t>(SymbolCache.size());
+  SymbolCache.push_back(llvm::make_unique<NativeExeSymbol>(*this, Id));
+  auto RawSymbol = SymbolCache[Id]->clone();
   auto PdbSymbol(PDBSymbol::create(*this, std::move(RawSymbol)));
   std::unique_ptr<PDBSymbolExe> ExeSymbol(
       static_cast<PDBSymbolExe *>(PdbSymbol.release()));
@@ -80,7 +94,10 @@ std::unique_ptr<PDBSymbolExe> NativeSession::getGlobalScope() {
 
 std::unique_ptr<PDBSymbol>
 NativeSession::getSymbolById(uint32_t SymbolId) const {
-  return nullptr;
+  // If the caller has a SymbolId, it'd better be in our SymbolCache.
+  return SymbolId < SymbolCache.size()
+             ? PDBSymbol::create(*this, SymbolCache[SymbolId]->clone())
+             : nullptr;
 }
 
 std::unique_ptr<PDBSymbol>