Refactor runtime support builder.

Also, add inline assembly for load offset from current thread.

Change-Id: I5c32c04a5ab9a8574acbaf8ee3e08761ebe33d4f
diff --git a/src/compiler_llvm/compilation_unit.cc b/src/compiler_llvm/compilation_unit.cc
index b4bdd5d..266377e 100644
--- a/src/compiler_llvm/compilation_unit.cc
+++ b/src/compiler_llvm/compilation_unit.cc
@@ -142,10 +142,8 @@
     irb_->SetInsertPoint(bb->getTerminator());
 
     using art::compiler_llvm::runtime_support::TestSuspend;
-    using art::compiler_llvm::runtime_support::GetCurrentThread;
     llvm::Value* runtime_func = irb_->GetRuntime(TestSuspend);
-    llvm::Value* thread_object_addr = irb_->CreateCall(irb_->GetRuntime(GetCurrentThread));
-    irb_->CreateCall(runtime_func, thread_object_addr);
+    irb_->CreateCall(runtime_func, irb_->getJNull());
 
     return true;
   }