Revert "Revert "Revert "Revert "JIT root tables.""""

Test: 626-set-resolved-string, test-art-host, test-art-target
Test: run-libcore-tests.sh
Test: phone boots and runs

This reverts commit 3395fbc20bcd20948bec8958db91b304c17cacd8.

Change-Id: I104b73d093e3eb6a271d564cfdb9ab09c1c8cf24
diff --git a/compiler/optimizing/code_generator.cc b/compiler/optimizing/code_generator.cc
index 8b450e1..9f6b78a 100644
--- a/compiler/optimizing/code_generator.cc
+++ b/compiler/optimizing/code_generator.cc
@@ -1375,4 +1375,33 @@
   return klass->GetDisableIntrinsicFlagOffset().Uint32Value();
 }
 
+void CodeGenerator::EmitJitRoots(uint8_t* code,
+                                 Handle<mirror::ObjectArray<mirror::Object>> roots,
+                                 const uint8_t* roots_data,
+                                 Handle<mirror::DexCache> outer_dex_cache) {
+  DCHECK_EQ(static_cast<size_t>(roots->GetLength()), GetNumberOfJitRoots());
+  StackHandleScope<1> hs(Thread::Current());
+  MutableHandle<mirror::DexCache> h_dex_cache(hs.NewHandle<mirror::DexCache>(nullptr));
+  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
+  size_t index = 0;
+  for (auto& entry : jit_string_roots_) {
+    const DexFile& entry_dex_file = *entry.first.dex_file;
+    // Avoid the expensive FindDexCache call by checking if the string is
+    // in the compiled method's dex file.
+    h_dex_cache.Assign(IsSameDexFile(*outer_dex_cache->GetDexFile(), entry_dex_file)
+        ? outer_dex_cache.Get()
+        : class_linker->FindDexCache(hs.Self(), entry_dex_file));
+    mirror::String* string = class_linker->LookupString(
+        entry_dex_file, entry.first.string_index, h_dex_cache);
+    DCHECK(string != nullptr) << "JIT roots require strings to have been loaded";
+    // Ensure the string is strongly interned. This is a requirement on how the JIT
+    // handles strings. b/32995596
+    class_linker->GetInternTable()->InternStrong(string);
+    roots->Set(index, string);
+    entry.second = index;
+    ++index;
+  }
+  EmitJitRootPatches(code, roots_data);
+}
+
 }  // namespace art