Avoid use of std::string where we have const char*.
Removing the ClassHelper caused std::string creation for all calls to
Class::GetDescriptor and a significant performance regression. Make the
std::string an out argument so the caller can maintain it and its life time
while allowing GetDescriptor to return the common const char* case.
Don't generate GC maps when compilation is disabled.
Remove other uses of std::string that are occuring on critical paths.
Use the cheaper SkipClass in CompileMethod in CompilerDriver.
Specialize the utf8 as utf16 comparison code for the common shorter byte
encoding.
Force a bit of inlining, remove some UNLIKELYs (they are prone to pessimizing
code), add some LIKELYs.
x86-64 host 1-thread interpret-only of 57 apks:
Before: 29.539s
After: 23.467s
Regular compile:
Before: 1m35.347s
After: 1m20.056s
Bug: 16853450
Change-Id: Ic705ea24784bee24ab80084d06174cbf87d557ad
diff --git a/runtime/mirror/class.h b/runtime/mirror/class.h
index 2a3f104..4b37bef 100644
--- a/runtime/mirror/class.h
+++ b/runtime/mirror/class.h
@@ -965,11 +965,15 @@
template<typename Visitor>
void VisitEmbeddedImtAndVTable(const Visitor& visitor) NO_THREAD_SAFETY_ANALYSIS;
- std::string GetDescriptor() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+ // Get the descriptor of the class. In a few cases a std::string is required, rather than
+ // always create one the storage argument is populated and its internal c_str() returned. We do
+ // this to avoid memory allocation in the common case.
+ const char* GetDescriptor(std::string* storage) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+
+ const char* GetArrayDescriptor(std::string* storage) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
bool DescriptorEquals(const char* match) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
- std::string GetArrayDescriptor() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
const DexFile::ClassDef* GetClassDef() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);