[llvm] big archive recognition by the llvm-symbolizer (PR #150401)

[James Henderson via llvm-commits]

================
@@ -557,57 +558,149 @@ LLVMSymbolizer::getOrCreateObjectPair(const std::string &Path,
   if (!DbgObj)
     DbgObj = Obj;
   ObjectPair Res = std::make_pair(Obj, DbgObj);
-  std::string DbgObjPath = DbgObj->getFileName().str();
   auto Pair =
       ObjectPairForPathArch.emplace(std::make_pair(Path, ArchName), Res);
-  BinaryForPath.find(DbgObjPath)->second.pushEvictor([this, I = Pair.first]() {
-    ObjectPairForPathArch.erase(I);
-  });
+  std::string DbgObjPath = DbgObj->getFileName().str();
+  auto BinIter = BinaryForPath.find(DbgObjPath);
+  if (BinIter != BinaryForPath.end()) {
+    BinIter->second.pushEvictor(
+        [this, I = Pair.first]() { ObjectPairForPathArch.erase(I); });
+  }
   return Res;
 }
 
-Expected<ObjectFile *>
-LLVMSymbolizer::getOrCreateObject(const std::string &Path,
-                                  const std::string &ArchName) {
-  Binary *Bin;
+Expected<object::Binary *>
+LLVMSymbolizer::loadOrGetBinary(const std::string &Path) {
   auto Pair = BinaryForPath.emplace(Path, OwningBinary<Binary>());
   if (!Pair.second) {
-    Bin = Pair.first->second->getBinary();
     recordAccess(Pair.first->second);
-  } else {
-    Expected<OwningBinary<Binary>> BinOrErr = createBinary(Path);
-    if (!BinOrErr)
-      return BinOrErr.takeError();
+    return Pair.first->second->getBinary();
+  }
 
-    CachedBinary &CachedBin = Pair.first->second;
-    CachedBin = std::move(BinOrErr.get());
-    CachedBin.pushEvictor([this, I = Pair.first]() { BinaryForPath.erase(I); });
-    LRUBinaries.push_back(CachedBin);
-    CacheSize += CachedBin.size();
-    Bin = CachedBin->getBinary();
+  Expected<OwningBinary<Binary>> BinOrErr = createBinary(Path);
+  if (!BinOrErr) {
+    BinaryForPath.erase(Pair.first);
+    return BinOrErr.takeError();
   }
 
-  if (!Bin)
-    return static_cast<ObjectFile *>(nullptr);
+  CachedBinary &CachedBin = Pair.first->second;
+  CachedBin = std::move(*BinOrErr);
+  CachedBin.pushEvictor([this, I = Pair.first]() { BinaryForPath.erase(I); });
+  LRUBinaries.push_back(CachedBin);
+  CacheSize += CachedBin.size();
+  return CachedBin->getBinary();
+}
 
-  if (MachOUniversalBinary *UB = dyn_cast_or_null<MachOUniversalBinary>(Bin)) {
-    auto I = ObjectForUBPathAndArch.find(std::make_pair(Path, ArchName));
-    if (I != ObjectForUBPathAndArch.end())
-      return I->second.get();
-
-    Expected<std::unique_ptr<ObjectFile>> ObjOrErr =
-        UB->getMachOObjectForArch(ArchName);
-    if (!ObjOrErr) {
-      ObjectForUBPathAndArch.emplace(std::make_pair(Path, ArchName),
-                                     std::unique_ptr<ObjectFile>());
-      return ObjOrErr.takeError();
+Expected<ObjectFile *> LLVMSymbolizer::findOrCacheObject(
+    const ArchiveCacheKey &Key,
+    llvm::function_ref<Expected<std::unique_ptr<ObjectFile>>()> Loader,
+    const std::string &PathForBinaryCache) {
+
+  auto It = ObjectFileCache.find(Key);
+  if (It != ObjectFileCache.end())
+    return It->second.get();
+
+  Expected<std::unique_ptr<ObjectFile>> ObjOrErr = Loader();
+  if (!ObjOrErr) {
+    ObjectFileCache.emplace(Key, std::unique_ptr<ObjectFile>());
+    return ObjOrErr.takeError();
+  }
+
+  ObjectFile *Res = ObjOrErr->get();
+  auto NewEntry = ObjectFileCache.emplace(Key, std::move(*ObjOrErr));
+  auto CacheIter = BinaryForPath.find(PathForBinaryCache);
+  if (CacheIter != BinaryForPath.end())
+    CacheIter->second.pushEvictor(
+        [this, Iter = NewEntry.first]() { ObjectFileCache.erase(Iter); });
+  return Res;
+}
+
+Expected<ObjectFile *> LLVMSymbolizer::getOrCreateObjectFromArchive(
+    StringRef ArchivePath, StringRef MemberName, StringRef ArchName) {
+  Expected<object::Binary *> BinOrErr = loadOrGetBinary(ArchivePath.str());
+  if (!BinOrErr)
+    return BinOrErr.takeError();
+  object::Binary *Bin = *BinOrErr;
+
+  object::Archive *Archive = dyn_cast_if_present<object::Archive>(Bin);
+  if (!Archive)
+    return createStringError(std::errc::invalid_argument,
+                             "'%s' is not a valid archive",
+                             ArchivePath.str().c_str());
+
+  Error Err = Error::success();
+  // On AIX, archives can contain multiple members with the same name but
+  // different types. We need to check all matches and find one that matches
+  // both name and architecture.
+  for (auto &Child : Archive->children(Err, /*SkipInternal=*/true)) {
+    Expected<StringRef> NameOrErr = Child.getName();
+    if (!NameOrErr)
+      continue;
+    if (*NameOrErr == sys::path::filename(MemberName)) {
+      Expected<std::unique_ptr<object::Binary>> MemberOrErr =
+          Child.getAsBinary();
+      if (!MemberOrErr)
+        continue;
+
+      std::unique_ptr<object::Binary> Binary = std::move(*MemberOrErr);
+      if (auto *Obj = dyn_cast<object::ObjectFile>(Binary.get())) {
+        Triple::ArchType ObjArch = Obj->makeTriple().getArch();
+        Triple RequestedTriple;
+        RequestedTriple.setArch(Triple::getArchTypeForLLVMName(ArchName));
+        if (ObjArch != RequestedTriple.getArch())
+          continue;
+
+        ArchiveCacheKey CacheKey{ArchivePath.str(), MemberName.str(),
+                                 ArchName.str()};
+        Expected<ObjectFile *> Res = findOrCacheObject(
+            CacheKey,
+            [O = std::unique_ptr<ObjectFile>(
+                 Obj)]() mutable -> Expected<std::unique_ptr<ObjectFile>> {
+              return std::move(O);
+            },
+            ArchivePath.str());
+        Binary.release();
+        return Res;
+      }
+    }
+  }
+  if (Err)
+    return std::move(Err);
+  return createStringError(std::errc::invalid_argument,
+                           "no matching member '%s' with arch '%s' in '%s'",
+                           MemberName.str().c_str(), ArchName.str().c_str(),
+                           ArchivePath.str().c_str());
+}
+
+Expected<ObjectFile *>
+LLVMSymbolizer::getOrCreateObject(const std::string &Path,
+                                  const std::string &ArchName) {
+  // First check for archive(member) format - more efficient to check closing
+  // paren first.
+  size_t CloseParen = Path.rfind(')');
+  if (CloseParen != std::string::npos && CloseParen == Path.length() - 1) {
----------------
jh7370 wrote:

This isn't efficient at all, especially for the case where there is no closing paren (likely the common case), but even for the case where you have one. The only case you're interested in is if `CloseParen` is the last character in `Path`, so why not just do `if (Path.back() == ')')` (but be careful you don't have an empty string)?

https://github.com/llvm/llvm-project/pull/150401