Use `std::string_view` for `ClassTable` operations.

Use `std::string_view` instead of `const char*` descriptor.
This uses faster `memcmp` instead of the slower`strcmp` for
descriptor comparison.

Note that the `ScopedTrace` passes `const char*` across the
`libartpalette` boundary, so we cannot easily replace the
`const char* descriptor` with `std::string_view descriptor`
in certain `ClassLinker` functions because we actually need
to pass a null-terminated string and the `string_view` API
does not technically guarantee null-terminated data.
Therefore we resort to explicitly passing around the
descriptor and its length as separate arguments.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 181943478
Bug: 338123769
Change-Id: Ie3fa251390acc582c54b4686d18696eb89b32361

1 files changed, 2 insertions, 3 deletions

diff --git a/runtime/mirror/class.h b/runtime/mirror/class.h
index 6384bfabc0..9560f985ac 100644
--- a/runtime/mirror/class.h
+++ b/runtime/mirror/class.h
@@ -1252,7 +1252,7 @@ class EXPORT MANAGED Class final : public Object {
   const char* GetDescriptor(std::string* storage) REQUIRES_SHARED(Locks::mutator_lock_);
 
   bool DescriptorEquals(ObjPtr<mirror::Class> match) REQUIRES_SHARED(Locks::mutator_lock_);
-  bool DescriptorEquals(const char* match) REQUIRES_SHARED(Locks::mutator_lock_);
+  bool DescriptorEquals(std::string_view match) REQUIRES_SHARED(Locks::mutator_lock_);
 
   uint32_t DescriptorHash() REQUIRES_SHARED(Locks::mutator_lock_);
 
@@ -1440,11 +1440,10 @@ class EXPORT MANAGED Class final : public Object {
   ALWAYS_INLINE uint32_t GetDirectMethodsStartOffset() REQUIRES_SHARED(Locks::mutator_lock_);
 
   bool ProxyDescriptorEquals(ObjPtr<mirror::Class> match) REQUIRES_SHARED(Locks::mutator_lock_);
-  bool ProxyDescriptorEquals(const char* match) REQUIRES_SHARED(Locks::mutator_lock_);
+  bool ProxyDescriptorEquals(std::string_view match) REQUIRES_SHARED(Locks::mutator_lock_);
   static uint32_t UpdateHashForProxyClass(uint32_t hash, ObjPtr<mirror::Class> proxy_class)
       REQUIRES_SHARED(Locks::mutator_lock_);
 
-
   template<VerifyObjectFlags kVerifyFlags>
   void GetAccessFlagsDCheck() REQUIRES_SHARED(Locks::mutator_lock_);