1 /*
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 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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24 
25 #ifndef CPU_X86_GLOBALDEFINITIONS_X86_HPP
26 #define CPU_X86_GLOBALDEFINITIONS_X86_HPP
27 
28 const int StackAlignmentInBytes  = 16;
29 const size_t pd_segfault_address = 1024;
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 #ifdef _LP64
38 #define SUPPORT_MONITOR_COUNT
39 #endif
40 
41 #define CPU_MULTI_COPY_ATOMIC
42 
43 // The expected size in bytes of a cache line.
44 #define DEFAULT_CACHE_LINE_SIZE 64
45 
46 // The default padding size for data structures to avoid false sharing.
47 #ifdef _LP64
48 // The common wisdom is that adjacent cache line prefetchers on some hardware
49 // may pull two cache lines on access, so we have to pessimistically assume twice
50 // the cache line size for padding. TODO: Check if this is still true for modern
51 // hardware. If not, DEFAULT_CACHE_LINE_SIZE might as well suffice.
52 #define DEFAULT_PADDING_SIZE (DEFAULT_CACHE_LINE_SIZE*2)
53 #else
54 #define DEFAULT_PADDING_SIZE DEFAULT_CACHE_LINE_SIZE
55 #endif
56 
57 #if defined(LINUX) || defined(__APPLE__)
58 #define SUPPORT_RESERVED_STACK_AREA
59 #endif
60 
61 #define USE_POINTERS_TO_REGISTER_IMPL_ARRAY
62 
63 #endif // CPU_X86_GLOBALDEFINITIONS_X86_HPP