Add AddImmediate(reg, int) to ARM64 assembler

runtime/vm/flow_graph_compiler_arm64.cc

Index: runtime/vm/flow_graph_compiler_arm64.cc
diff --git a/runtime/vm/flow_graph_compiler_arm64.cc b/runtime/vm/flow_graph_compiler_arm64.cc
index a6e37ded98089d15f8cb2f7f2a4a95b674a7be17..00d61566d17346788bf950eb8e5b891712558666 100644
--- a/runtime/vm/flow_graph_compiler_arm64.cc
+++ b/runtime/vm/flow_graph_compiler_arm64.cc
@@ -799,7 +799,7 @@ void FlowGraphCompiler::CopyParameters() {
     // Let R7 point to the first passed argument, i.e. to
     // fp[kParamEndSlotFromFp + num_args - 0]; num_args (R7) is Smi.
     __ add(R7, FP, Operand(R7, LSL, 2));
-    __ AddImmediate(R7, R7, kParamEndSlotFromFp * kWordSize);
+    __ AddImmediate(R7, kParamEndSlotFromFp * kWordSize);
     // Let R6 point to the entry of the first named argument.
     __ add(R6, R4, Operand(ArgumentsDescriptor::first_named_entry_offset() -
                            kHeapObjectTag));
@@ -1491,7 +1491,7 @@ int FlowGraphCompiler::EmitTestAndCallCheckCid(Label* next_label,
     __ CompareImmediate(R2, cid_start - bias);
     __ b(next_label, NE);
   } else {
-    __ AddImmediate(R2, R2, bias - cid_start);
+    __ AddImmediate(R2, bias - cid_start);
     bias = cid_start;
     __ CompareImmediate(R2, cid_end - cid_start);
     __ b(next_label, HI);  // Unsigned higher.