Cleanup String.<init> handling.

Move everything to one place (currently well_known_classes.cc, but
no strong preference) and define a macro to easily handle the list
of affected methods.

test: m test-art-host
test: m test-art-target
Change-Id: Ib8372d130d5458516a1f1ae31014afc76037fc34
diff --git a/compiler/optimizing/code_generator_arm64.cc b/compiler/optimizing/code_generator_arm64.cc
index 7160607..a2a2e42 100644
--- a/compiler/optimizing/code_generator_arm64.cc
+++ b/compiler/optimizing/code_generator_arm64.cc
@@ -3570,10 +3570,13 @@
   // Make sure that ArtMethod* is passed in kArtMethodRegister as per the calling convention.
   Location callee_method = temp;  // For all kinds except kRecursive, callee will be in temp.
   switch (invoke->GetMethodLoadKind()) {
-    case HInvokeStaticOrDirect::MethodLoadKind::kStringInit:
+    case HInvokeStaticOrDirect::MethodLoadKind::kStringInit: {
+      uint32_t offset =
+          GetThreadOffset<kArm64PointerSize>(invoke->GetStringInitEntryPoint()).Int32Value();
       // temp = thread->string_init_entrypoint
-      __ Ldr(XRegisterFrom(temp), MemOperand(tr, invoke->GetStringInitOffset()));
+      __ Ldr(XRegisterFrom(temp), MemOperand(tr, offset));
       break;
+    }
     case HInvokeStaticOrDirect::MethodLoadKind::kRecursive:
       callee_method = invoke->GetLocations()->InAt(invoke->GetSpecialInputIndex());
       break;