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  25 
  26 #ifndef CPU_AARCH64_GLOBALDEFINITIONS_AARCH64_HPP
  27 #define CPU_AARCH64_GLOBALDEFINITIONS_AARCH64_HPP
  28 
  29 const int StackAlignmentInBytes  = 16;
  30 
  31 // Indicates whether the C calling conventions require that
  32 // 32-bit integer argument values are extended to 64 bits.
  33 const bool CCallingConventionRequiresIntsAsLongs = false;
  34 
  35 #define SUPPORTS_NATIVE_CX8
  36 
  37 // aarch64 is not CPU_MULTI_COPY_ATOMIC
  38 
  39 // According to the ARMv8 ARM, "Concurrent modification and execution
  40 // of instructions can lead to the resulting instruction performing
  41 // any behavior that can be achieved by executing any sequence of
  42 // instructions that can be executed from the same Exception level,
  43 // except where the instruction before modification and the
  44 // instruction after modification is a B, BL, NOP, BKPT, SVC, HVC, or
  45 // SMC instruction."
  46 //
  47 // This makes the games we play when patching difficult, so when we
  48 // come across an access that needs patching we deoptimize.  There are
  49 // ways we can avoid this, but these would slow down C1-compiled code
  50 // in the defauilt case.  We could revisit this decision if we get any
  51 // evidence that it's worth doing.
  52 #define DEOPTIMIZE_WHEN_PATCHING
  53 
  54 #define SUPPORT_RESERVED_STACK_AREA
  55 
  56 #define THREAD_LOCAL_POLL
  57 
  58 #endif // CPU_AARCH64_GLOBALDEFINITIONS_AARCH64_HPP