Improve dex location canonicalization-related performance.

Eagerly add canonical dex file locations to the OatFile's
primary lookup map in Setup(). This moves the boot.oat work
from every app startup to the zygote initialization. Since
we always ended up initializing the canonical location map
anyway due to the way that we're loading dex files, the lazy
initialization didn't save anything.

Clean up dex file name canonicalization to make sure we
free() the memory returned by realpath() rather than using
std::unique_ptr<> with the default deleter.

Avoid some unnecessary duplicate OatDexFile lookups.

Bug: 16828525
Bug: 17346103
Change-Id: Id8fbc8992f62996138eb2006a0046c6529747c09

1 files changed, 13 insertions, 0 deletions

diff --git a/runtime/utils.h b/runtime/utils.h
index 7fb5bbd3da..50462b11b3 100644
--- a/runtime/utils.h
+++ b/runtime/utils.h
@@ -20,6 +20,7 @@
 #include <pthread.h>
 
 #include <limits>
+#include <memory>
 #include <string>
 #include <vector>
 
@@ -502,6 +503,18 @@ void PushWord(std::vector<uint8_t>* buf, int32_t data);
 void EncodeUnsignedLeb128(uint32_t data, std::vector<uint8_t>* buf);
 void EncodeSignedLeb128(int32_t data, std::vector<uint8_t>* buf);
 
+// Deleter using free() for use with std::unique_ptr<>. See also UniqueCPtr<> below.
+struct FreeDelete {
+  // NOTE: Deleting a const object is valid but free() takes a non-const pointer.
+  void operator()(const void* ptr) const {
+    free(const_cast<void*>(ptr));
+  }
+};
+
+// Alias for std::unique_ptr<> that uses the C function free() to delete objects.
+template <typename T>
+using UniqueCPtr = std::unique_ptr<T, FreeDelete>;
+
 }  // namespace art
 
 #endif  // ART_RUNTIME_UTILS_H_