The IC exposes a register definition.

src/arm/ic-arm.cc

Index: src/arm/ic-arm.cc
diff --git a/src/arm/ic-arm.cc b/src/arm/ic-arm.cc
index 1028f8fd2b81fe6c5599ca26a6d243129b453aff..1fa1a859eadcf77e102a899f15934c159590a9cc 100644
--- a/src/arm/ic-arm.cc
+++ b/src/arm/ic-arm.cc
@@ -545,6 +545,21 @@ void KeyedLoadIC::GenerateMiss(MacroAssembler* masm) {
 }
 
 
+// IC register specifications
+const Register LoadIC::ReceiverRegister() { return r0; }
+const Register LoadIC::NameRegister() { return r2; }
+const Register KeyedLoadIC::ReceiverRegister() { return r1; }
+const Register KeyedLoadIC::NameRegister() { return r0; }
+
+
+const Register* KeyedLoadIC::AllocateRegisterArray() {
+  Register* registers = new Register[kRegisterArgumentCount];
+  registers[0] = ReceiverRegister();
+  registers[1] = NameRegister();
+  return registers;
+}
+
+
 void KeyedLoadIC::GenerateRuntimeGetProperty(MacroAssembler* masm) {
   // ---------- S t a t e --------------
   //  -- lr     : return address