8202579: Revisit VM_Version and VM_Version_ext for overlap and consolidation

Reviewed-by: dholmes, hseigel

Author: coleenp

src/hotspot/cpu/aarch64/vm_version_aarch64.cpp

@@ -488,3 +488,22 @@ void VM_Version::initialize() {
 
   _spin_wait = get_spin_wait_desc();
 }
+
+void VM_Version::initialize_cpu_information(void) {
+  // do nothing if cpu info has been initialized
+  if (_initialized) {
+    return;
+  }
+
+  _no_of_cores  = os::processor_count();
+  _no_of_threads = _no_of_cores;
+  _no_of_sockets = _no_of_cores;
+  snprintf(_cpu_name, CPU_TYPE_DESC_BUF_SIZE - 1, "AArch64");
+
+  int desc_len = snprintf(_cpu_desc, CPU_DETAILED_DESC_BUF_SIZE, "AArch64 ");
+  get_compatible_board(_cpu_desc + desc_len, CPU_DETAILED_DESC_BUF_SIZE - desc_len);
+  desc_len = (int)strlen(_cpu_desc);
+  snprintf(_cpu_desc + desc_len, CPU_DETAILED_DESC_BUF_SIZE - desc_len, " %s", _features_string);
+
+  _initialized = true;
+}

src/hotspot/cpu/aarch64/vm_version_aarch64.hpp

@@ -153,6 +153,9 @@ class VM_Version : public Abstract_VM_Version {
   // Is the CPU running emulated (for example macOS Rosetta running x86_64 code on M1 ARM (aarch64)
   static bool is_cpu_emulated();
 #endif
+
+  static void initialize_cpu_information(void);
+
 };
 
 #endif // CPU_AARCH64_VM_VERSION_AARCH64_HPP

src/hotspot/cpu/aarch64/vm_version_ext_aarch64.cpp

@@ -106,6 +106,7 @@ class VM_Version: public Abstract_VM_Version {
 
   friend class VM_Version_StubGenerator;
 
+  static void initialize_cpu_information(void);
 };
 
 #endif // CPU_ARM_VM_VERSION_ARM_HPP

src/hotspot/cpu/aarch64/vm_version_ext_aarch64.hpp

@@ -347,3 +347,17 @@ void VM_Version::initialize() {
 
   _is_initialized = true;
 }
+
+void VM_Version::initialize_cpu_information(void) {
+  // do nothing if cpu info has been initialized
+  if (_initialized) {
+    return;
+  }
+
+  _no_of_cores  = os::processor_count();
+  _no_of_threads = _no_of_cores;
+  _no_of_sockets = _no_of_cores;
+  snprintf(_cpu_name, CPU_TYPE_DESC_BUF_SIZE - 1, "ARM%d", _arm_arch);
+  snprintf(_cpu_desc, CPU_DETAILED_DESC_BUF_SIZE, "%s", _features_string);
+  _initialized = true;
+}