[arm64][Liftoff] implement trap instructions

Define and use TurboAssembler::AssertUnreachable

Bug: v8:6600
Change-Id: I6901896ea4fd7e0fe24dd76a1afbb409a24a2994
Reviewed-on: https://chromium-review.googlesource.com/1040766
Commit-Queue: Vincent Belliard <vincent.belliard@arm.com>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52963}

src/arm64/macro-assembler-arm64.cc

@@ -3012,6 +3012,10 @@ void TurboAssembler::Assert(Condition cond, AbortReason reason) {
   }
 }
 
+void TurboAssembler::AssertUnreachable(AbortReason reason) {
+  if (emit_debug_code()) Abort(reason);
+}
+
 void MacroAssembler::AssertRegisterIsRoot(Register reg,
                                           Heap::RootListIndex index,
                                           AbortReason reason) {

src/arm64/macro-assembler-arm64.h

@@ -590,6 +590,10 @@ class TurboAssembler : public Assembler {
   // Use --debug_code to enable.
   void Assert(Condition cond, AbortReason reason);
 
+  // Like Assert(), but without condition.
+  // Use --debug_code to enable.
+  void AssertUnreachable(AbortReason reason);
+
   void AssertSmi(Register object,
                  AbortReason reason = AbortReason::kOperandIsNotASmi);
 

src/wasm/baseline/arm64/liftoff-assembler-arm64.h

@@ -619,11 +619,11 @@ void LiftoffAssembler::StackCheck(Label* ool_code) {
 }
 
 void LiftoffAssembler::CallTrapCallbackForTesting() {
-  BAILOUT("CallTrapCallbackForTesting");
+  CallCFunction(ExternalReference::wasm_call_trap_callback_for_testing(), 0);
 }
 
 void LiftoffAssembler::AssertUnreachable(AbortReason reason) {
-  BAILOUT("AssertUnreachable");
+  TurboAssembler::AssertUnreachable(reason);
 }
 
 void LiftoffAssembler::PushRegisters(LiftoffRegList regs) {