Make ART compile with GCC -O0 again.

Tidy up InstructionSetFeatures so that it has a type hierarchy dependent on
architecture.
Add to instruction_set_test to warn when InstructionSetFeatures don't agree
with ones from system properties, AT_HWCAP and /proc/cpuinfo.
Clean-up class linker entry point logic to not return entry points but to
test whether the passed code is the particular entrypoint. This works around
image trampolines that replicate entrypoints.
Bug: 17993736

Change-Id: I5f4b49e88c3b02a79f9bee04f83395146ed7be23
diff --git a/runtime/base/logging.cc b/runtime/base/logging.cc
index b2ad1d0..5af597b 100644
--- a/runtime/base/logging.cc
+++ b/runtime/base/logging.cc
@@ -85,7 +85,7 @@
   }
 
   std::vector<std::string> specs;
-  Split(tags, ' ', specs);
+  Split(tags, ' ', &specs);
   for (size_t i = 0; i < specs.size(); ++i) {
     // "tag-pattern:[vdiwefs]"
     std::string spec(specs[i]);
diff --git a/runtime/base/macros.h b/runtime/base/macros.h
index f5a38bb..c80d35e 100644
--- a/runtime/base/macros.h
+++ b/runtime/base/macros.h
@@ -63,6 +63,11 @@
 #define COMPILE_ASSERT(expr, msg) \
   typedef CompileAssert<(bool(expr))> msg[bool(expr) ? 1 : -1] // NOLINT
 
+// Declare a friend relationship in a class with a test. Used rather that FRIEND_TEST to avoid
+// globally importing gtest/gtest.h into the main ART header files.
+#define ART_FRIEND_TEST(test_set_name, individual_test)\
+friend class test_set_name##_##individual_test##_Test
+
 // DISALLOW_COPY_AND_ASSIGN disallows the copy and operator= functions.
 // It goes in the private: declarations in a class.
 #define DISALLOW_COPY_AND_ASSIGN(TypeName) \
diff --git a/runtime/base/mutex.cc b/runtime/base/mutex.cc
index cbcd408..70b6f7e 100644
--- a/runtime/base/mutex.cc
+++ b/runtime/base/mutex.cc
@@ -83,18 +83,25 @@
 }
 #endif
 
-class ScopedAllMutexesLock {
+class ScopedAllMutexesLock FINAL {
  public:
   explicit ScopedAllMutexesLock(const BaseMutex* mutex) : mutex_(mutex) {
     while (!gAllMutexData->all_mutexes_guard.CompareExchangeWeakAcquire(0, mutex)) {
       NanoSleep(100);
     }
   }
+
   ~ScopedAllMutexesLock() {
+#if !defined(__clang__)
+    // TODO: remove this workaround target GCC/libc++/bionic bug "invalid failure memory model".
+    while (!gAllMutexData->all_mutexes_guard.CompareExchangeWeakSequentiallyConsistent(mutex_, 0)) {
+#else
     while (!gAllMutexData->all_mutexes_guard.CompareExchangeWeakRelease(mutex_, 0)) {
+#endif
       NanoSleep(100);
     }
   }
+
  private:
   const BaseMutex* const mutex_;
 };