ARM64: Check size of code generated in ProfileEntryHookStub::MaybeCallEntryHook.

src/arm64/code-stubs-arm64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 4891 matching lines @@
   if (function_mode_ == JS_FUNCTION_STUB_MODE) {
     __ Add(x1, x1, 1);
   }
   masm->LeaveFrame(StackFrame::STUB_FAILURE_TRAMPOLINE);
   __ Drop(x1);
   // Return to IC Miss stub, continuation still on stack.
   __ Ret();
 }
 
 
+// The entry hook is a "BumpSystemStackPointer" instruction (sub), followed by
+// a "Push lr" instruction, followed by a call.
+static const unsigned int kProfileEntryHookCallSize =
+    Assembler::kCallSizeWithRelocation + (2 * kInstructionSize);
+
+
 void ProfileEntryHookStub::MaybeCallEntryHook(MacroAssembler* masm) {
   if (masm->isolate()->function_entry_hook() != NULL) {
-    // TODO(all): This needs to be reliably consistent with
-    // kReturnAddressDistanceFromFunctionStart in ::Generate.
-    Assembler::BlockPoolsScope no_pools(masm);
     ProfileEntryHookStub stub;
+    Assembler::BlockConstPoolScope no_const_pools(masm);
+    Label entry_hook_call_start;
+    __ Bind(&entry_hook_call_start);
     __ Push(lr);
     __ CallStub(&stub);
+    ASSERT(masm->SizeOfCodeGeneratedSince(&entry_hook_call_start) ==
+           kProfileEntryHookCallSize);
+
     __ Pop(lr);
   }
 }
 
 
 void ProfileEntryHookStub::Generate(MacroAssembler* masm) {
   MacroAssembler::NoUseRealAbortsScope no_use_real_aborts(masm);
-  // The entry hook is a "BumpSystemStackPointer" instruction (sub), followed by
-  // a "Push lr" instruction, followed by a call.
-  static const int kReturnAddressDistanceFromFunctionStart =
-      Assembler::kCallSizeWithRelocation + (2 * kInstructionSize);
 
   // Save all kCallerSaved registers (including lr), since this can be called
   // from anywhere.
   // TODO(jbramley): What about FP registers?
   __ PushCPURegList(kCallerSaved);
   ASSERT(kCallerSaved.IncludesAliasOf(lr));
   const int kNumSavedRegs = kCallerSaved.Count();
 
   // Compute the function's address as the first argument.
-  __ Sub(x0, lr, kReturnAddressDistanceFromFunctionStart);
+  __ Sub(x0, lr, kProfileEntryHookCallSize);
 
 #if V8_HOST_ARCH_ARM64
   uintptr_t entry_hook =
       reinterpret_cast<uintptr_t>(masm->isolate()->function_entry_hook());
   __ Mov(x10, entry_hook);
 #else
   // Under the simulator we need to indirect the entry hook through a trampoline
   // function at a known address.
   ApiFunction dispatcher(FUNCTION_ADDR(EntryHookTrampoline));
   __ Mov(x10, Operand(ExternalReference(&dispatcher,
@@ skipping 775 matching lines @@
                               MemOperand(fp, 6 * kPointerSize),
                               NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM64