The IC exposes a register definition.

src/arm/stub-cache-arm.cc

Index: src/arm/stub-cache-arm.cc
diff --git a/src/arm/stub-cache-arm.cc b/src/arm/stub-cache-arm.cc
index 23ee05d84b26207151388439c034eb7b6ecb0773..e807314f332502be717eac028f2a9ec20a13c219 100644
--- a/src/arm/stub-cache-arm.cc
+++ b/src/arm/stub-cache-arm.cc
@@ -1263,14 +1263,18 @@ Handle<Code> LoadStubCompiler::CompileLoadNonexistent(Handle<HeapType> type,
 
 Register* LoadStubCompiler::registers() {
   // receiver, name, scratch1, scratch2, scratch3, scratch4.
-  static Register registers[] = { r0, r2, r3, r1, r4, r5 };
+  Register receiver = LoadIC::ReceiverRegister();
+  Register name = LoadIC::NameRegister();
+  static Register registers[] = { receiver, name, r3, r1, r4, r5 };
   return registers;
 }
 
 
 Register* KeyedLoadStubCompiler::registers() {
   // receiver, name, scratch1, scratch2, scratch3, scratch4.
-  static Register registers[] = { r1, r0, r2, r3, r4, r5 };
+  Register receiver = KeyedLoadIC::ReceiverRegister();
+  Register name = KeyedLoadIC::NameRegister();
+  static Register registers[] = { receiver, name, r2, r3, r4, r5 };
   return registers;
 }