A64: Tidy up a couple of TODOs.

src/a64/macro-assembler-a64.cc

Index: src/a64/macro-assembler-a64.cc
diff --git a/src/a64/macro-assembler-a64.cc b/src/a64/macro-assembler-a64.cc
index 53c7777ae137b62b162ee3a80050f81891f28f9a..5160bea8e0d244f427e6aaabc32e13633f4fe624 100644
--- a/src/a64/macro-assembler-a64.cc
+++ b/src/a64/macro-assembler-a64.cc
@@ -1497,12 +1497,7 @@ void MacroAssembler::AssertNotSmi(Register object, BailoutReason reason) {
 
 void MacroAssembler::AssertName(Register object) {
   if (emit_debug_code()) {
-    STATIC_ASSERT(kSmiTag == 0);
-    // TODO(jbramley): Add AbortIfSmi and related functions.
-    Label not_smi;
-    JumpIfNotSmi(object, &not_smi);
-    Abort(kOperandIsASmiAndNotAName);
-    Bind(&not_smi);
+    AssertNotSmi(object, kOperandIsASmiAndNotAName);
 
     Ldr(Tmp1(), FieldMemOperand(object, HeapObject::kMapOffset));
     CompareInstanceType(Tmp1(), Tmp1(), LAST_NAME_TYPE);
@@ -2808,8 +2803,6 @@ void MacroAssembler::TruncateHeapNumberToI(Register result,
 void MacroAssembler::Prologue(PrologueFrameMode frame_mode) {
   if (frame_mode == BUILD_STUB_FRAME) {
     ASSERT(StackPointer().Is(jssp));
-    // TODO(jbramley): Does x1 contain a JSFunction here, or does it already
-    // have the special STUB smi?
     __ Mov(Tmp0(), Operand(Smi::FromInt(StackFrame::STUB)));
     // Compiled stubs don't age, and so they don't need the predictable code
     // ageing sequence.