478 
 479 /////////////////////////////////////////////////////////////////////////////
 480 // Implementations of atomic operations not supported by processors.
 481 //  -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html
 482 
 483 #ifndef _LP64
 484 extern "C" {
 485   long long unsigned int __sync_val_compare_and_swap_8(
 486     volatile void *ptr,
 487     long long unsigned int oldval,
 488     long long unsigned int newval) {
 489     ShouldNotCallThis();
 490   }
 491 };
 492 #endif // !_LP64
 493 
 494 #ifndef PRODUCT
 495 void os::verify_stack_alignment() {
 496 }
 497 #endif

 478 
 479 /////////////////////////////////////////////////////////////////////////////
 480 // Implementations of atomic operations not supported by processors.
 481 //  -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html
 482 
 483 #ifndef _LP64
 484 extern "C" {
 485   long long unsigned int __sync_val_compare_and_swap_8(
 486     volatile void *ptr,
 487     long long unsigned int oldval,
 488     long long unsigned int newval) {
 489     ShouldNotCallThis();
 490   }
 491 };
 492 #endif // !_LP64
 493 
 494 #ifndef PRODUCT
 495 void os::verify_stack_alignment() {
 496 }
 497 #endif
 498 
 499 int os::extra_bang_size_in_bytes() {
 500   // JDK-8050147 requires the full cache line bang for x86.
 501   return VM_Version::L1_line_size();
 502 }