Replace String CharArray with internal uint16_t array.

Summary of high level changes:
  - Adds compiler inliner support to identify string init methods
  - Adds compiler support (quick & optimizing) with new invoke code path
    that calls method off the thread pointer
  - Adds thread entrypoints for all string init methods
  - Adds map to verifier to log when receiver of string init has been
    copied to other registers. used by compiler and interpreter

Change-Id: I797b992a8feb566f9ad73060011ab6f51eb7ce01
diff --git a/runtime/native/java_lang_String.cc b/runtime/native/java_lang_String.cc
index 2d153d4..aa64b79 100644
--- a/runtime/native/java_lang_String.cc
+++ b/runtime/native/java_lang_String.cc
@@ -18,6 +18,9 @@
 
 #include "common_throws.h"
 #include "jni_internal.h"
+#include "mirror/array.h"
+#include "mirror/object-inl.h"
+#include "mirror/string.h"
 #include "mirror/string-inl.h"
 #include "scoped_fast_native_object_access.h"
 #include "scoped_thread_state_change.h"
@@ -26,36 +29,93 @@
 
 namespace art {
 
-static jint String_compareTo(JNIEnv* env, jobject javaThis, jobject javaRhs) {
+static jchar String_charAt(JNIEnv* env, jobject java_this, jint index) {
   ScopedFastNativeObjectAccess soa(env);
-  if (UNLIKELY(javaRhs == nullptr)) {
+  return soa.Decode<mirror::String*>(java_this)->CharAt(index);
+}
+
+static jint String_compareTo(JNIEnv* env, jobject java_this, jobject java_rhs) {
+  ScopedFastNativeObjectAccess soa(env);
+  if (UNLIKELY(java_rhs == nullptr)) {
     ThrowNullPointerException("rhs == null");
     return -1;
   } else {
-    return soa.Decode<mirror::String*>(javaThis)->CompareTo(soa.Decode<mirror::String*>(javaRhs));
+    return soa.Decode<mirror::String*>(java_this)->CompareTo(soa.Decode<mirror::String*>(java_rhs));
   }
 }
 
+static jstring String_concat(JNIEnv* env, jobject java_this, jobject java_string_arg) {
+  ScopedFastNativeObjectAccess soa(env);
+  if (UNLIKELY(java_string_arg == nullptr)) {
+    ThrowNullPointerException("string arg == null");
+    return nullptr;
+  }
+  StackHandleScope<2> hs(soa.Self());
+  Handle<mirror::String> string_this(hs.NewHandle(soa.Decode<mirror::String*>(java_this)));
+  Handle<mirror::String> string_arg(hs.NewHandle(soa.Decode<mirror::String*>(java_string_arg)));
+  int32_t length_this = string_this->GetLength();
+  int32_t length_arg = string_arg->GetLength();
+  if (length_arg > 0 && length_this > 0) {
+    mirror::String* result = mirror::String::AllocFromStrings(soa.Self(), string_this, string_arg);
+    return soa.AddLocalReference<jstring>(result);
+  }
+  jobject string_original = (length_this == 0) ? java_string_arg : java_this;
+  return reinterpret_cast<jstring>(string_original);
+}
+
 static jint String_fastIndexOf(JNIEnv* env, jobject java_this, jint ch, jint start) {
   ScopedFastNativeObjectAccess soa(env);
   // This method does not handle supplementary characters. They're dealt with in managed code.
   DCHECK_LE(ch, 0xffff);
-
-  mirror::String* s = soa.Decode<mirror::String*>(java_this);
-  return s->FastIndexOf(ch, start);
+  return soa.Decode<mirror::String*>(java_this)->FastIndexOf(ch, start);
 }
 
-static jstring String_intern(JNIEnv* env, jobject javaThis) {
+static jstring String_fastSubstring(JNIEnv* env, jobject java_this, jint start, jint length) {
   ScopedFastNativeObjectAccess soa(env);
-  mirror::String* s = soa.Decode<mirror::String*>(javaThis);
+  StackHandleScope<1> hs(soa.Self());
+  Handle<mirror::String> string_this(hs.NewHandle(soa.Decode<mirror::String*>(java_this)));
+  gc::AllocatorType allocator_type = Runtime::Current()->GetHeap()->GetCurrentAllocator();
+  mirror::String* result = mirror::String::AllocFromString<true>(soa.Self(), length, string_this,
+                                                                 start, allocator_type);
+  return soa.AddLocalReference<jstring>(result);
+}
+
+static void String_getCharsNoCheck(JNIEnv* env, jobject java_this, jint start, jint end,
+                                   jcharArray buffer, jint index) {
+  ScopedFastNativeObjectAccess soa(env);
+  StackHandleScope<1> hs(soa.Self());
+  Handle<mirror::CharArray> char_array(hs.NewHandle(soa.Decode<mirror::CharArray*>(buffer)));
+  soa.Decode<mirror::String*>(java_this)->GetChars(start, end, char_array, index);
+}
+
+static jstring String_intern(JNIEnv* env, jobject java_this) {
+  ScopedFastNativeObjectAccess soa(env);
+  mirror::String* s = soa.Decode<mirror::String*>(java_this);
   mirror::String* result = s->Intern();
   return soa.AddLocalReference<jstring>(result);
 }
 
+static void String_setCharAt(JNIEnv* env, jobject java_this, jint index, jchar c) {
+  ScopedFastNativeObjectAccess soa(env);
+  soa.Decode<mirror::String*>(java_this)->SetCharAt(index, c);
+}
+
+static jcharArray String_toCharArray(JNIEnv* env, jobject java_this) {
+  ScopedFastNativeObjectAccess soa(env);
+  mirror::String* s = soa.Decode<mirror::String*>(java_this);
+  return soa.AddLocalReference<jcharArray>(s->ToCharArray(soa.Self()));
+}
+
 static JNINativeMethod gMethods[] = {
+  NATIVE_METHOD(String, charAt, "!(I)C"),
   NATIVE_METHOD(String, compareTo, "!(Ljava/lang/String;)I"),
+  NATIVE_METHOD(String, concat, "!(Ljava/lang/String;)Ljava/lang/String;"),
   NATIVE_METHOD(String, fastIndexOf, "!(II)I"),
+  NATIVE_METHOD(String, fastSubstring, "!(II)Ljava/lang/String;"),
+  NATIVE_METHOD(String, getCharsNoCheck, "!(II[CI)V"),
   NATIVE_METHOD(String, intern, "!()Ljava/lang/String;"),
+  NATIVE_METHOD(String, setCharAt, "!(IC)V"),
+  NATIVE_METHOD(String, toCharArray, "!()[C"),
 };
 
 void register_java_lang_String(JNIEnv* env) {