Thu, 04 Sep 2014 16:53:27 -0700
8057531: refactor gc argument processing code slightly
Reviewed-by: mgerdin, tschatzl, jmasa
1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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13 * accompanied this code).
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25 #ifndef SHARE_VM_RUNTIME_VM_VERSION_HPP
26 #define SHARE_VM_RUNTIME_VM_VERSION_HPP
28 #include "memory/allocation.hpp"
29 #include "utilities/ostream.hpp"
31 // VM_Version provides information about the VM.
33 class Abstract_VM_Version: AllStatic {
34 protected:
35 friend class VMStructs;
36 static const char* _s_vm_release;
37 static const char* _s_internal_vm_info_string;
38 // These are set by machine-dependent initializations
39 static bool _supports_cx8;
40 static bool _supports_atomic_getset4;
41 static bool _supports_atomic_getset8;
42 static bool _supports_atomic_getadd4;
43 static bool _supports_atomic_getadd8;
44 static unsigned int _logical_processors_per_package;
45 static int _vm_major_version;
46 static int _vm_minor_version;
47 static int _vm_build_number;
48 static bool _initialized;
49 static int _parallel_worker_threads;
50 static bool _parallel_worker_threads_initialized;
51 static int _reserve_for_allocation_prefetch;
53 static unsigned int nof_parallel_worker_threads(unsigned int num,
54 unsigned int dem,
55 unsigned int switch_pt);
56 public:
57 static void initialize();
59 // Name
60 static const char* vm_name();
61 // Vendor
62 static const char* vm_vendor();
63 // VM version information string printed by launcher (java -version)
64 static const char* vm_info_string();
65 static const char* vm_release();
66 static const char* vm_platform_string();
67 static const char* vm_build_user();
69 static int vm_major_version() { assert(_initialized, "not initialized"); return _vm_major_version; }
70 static int vm_minor_version() { assert(_initialized, "not initialized"); return _vm_minor_version; }
71 static int vm_build_number() { assert(_initialized, "not initialized"); return _vm_build_number; }
73 // Gets the jvm_version_info.jvm_version defined in jvm.h
74 static unsigned int jvm_version();
76 // Internal version providing additional build information
77 static const char* internal_vm_info_string();
78 static const char* jre_release_version();
80 // does HW support an 8-byte compare-exchange operation?
81 static bool supports_cx8() {
82 #ifdef SUPPORTS_NATIVE_CX8
83 return true;
84 #else
85 return _supports_cx8;
86 #endif
87 }
88 // does HW support atomic get-and-set or atomic get-and-add? Used
89 // to guide intrinsification decisions for Unsafe atomic ops
90 static bool supports_atomic_getset4() {return _supports_atomic_getset4;}
91 static bool supports_atomic_getset8() {return _supports_atomic_getset8;}
92 static bool supports_atomic_getadd4() {return _supports_atomic_getadd4;}
93 static bool supports_atomic_getadd8() {return _supports_atomic_getadd8;}
95 static unsigned int logical_processors_per_package() {
96 return _logical_processors_per_package;
97 }
99 // Need a space at the end of TLAB for prefetch instructions
100 // which may fault when accessing memory outside of heap.
101 static int reserve_for_allocation_prefetch() {
102 return _reserve_for_allocation_prefetch;
103 }
105 // ARCH specific policy for the BiasedLocking
106 static bool use_biased_locking() { return true; }
108 // Number of page sizes efficiently supported by the hardware. Most chips now
109 // support two sizes, thus this default implementation. Processor-specific
110 // subclasses should define new versions to hide this one as needed. Note
111 // that the O/S may support more sizes, but at most this many are used.
112 static uint page_size_count() { return 2; }
114 // Returns the number of parallel threads to be used for VM
115 // work. If that number has not been calculated, do so and
116 // save it. Returns ParallelGCThreads if it is set on the
117 // command line.
118 static unsigned int parallel_worker_threads();
119 // Calculates and returns the number of parallel threads. May
120 // be VM version specific.
121 static unsigned int calc_parallel_worker_threads();
122 };
124 #endif // SHARE_VM_RUNTIME_VM_VERSION_HPP