Version 2.5.4

src/platform-linux.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 81 matching lines @@
   return 1u << VFP3;
 #elif CAN_USE_ARMV7_INSTRUCTIONS
   return 1u << ARMv7;
 #else
   return 0;  // Linux runs on anything.
 #endif
 }
 
 
 #ifdef __arm__
-bool OS::ArmCpuHasFeature(CpuFeature feature) {
-  const char* search_string = NULL;
+static bool CPUInfoContainsString(const char * search_string) {
   const char* file_name = "/proc/cpuinfo";
-  // Simple detection of VFP at runtime for Linux.
-  // It is based on /proc/cpuinfo, which reveals hardware configuration
-  // to user-space applications.  According to ARM (mid 2009), no similar
-  // facility is universally available on the ARM architectures,
-  // so it's up to individual OSes to provide such.
-  //
   // This is written as a straight shot one pass parser
   // and not using STL string and ifstream because,
   // on Linux, it's reading from a (non-mmap-able)
   // character special device.
-  switch (feature) {
-    case VFP3:
-      search_string = "vfp";
-      break;
-    case ARMv7:
-      search_string = "ARMv7";
-      break;
-    default:
-      UNREACHABLE();
-  }
-
   FILE* f = NULL;
   const char* what = search_string;
 
   if (NULL == (f = fopen(file_name, "r")))
     return false;
 
   int k;
   while (EOF != (k = fgetc(f))) {
     if (k == *what) {
       ++what;
       while ((*what != '\0') && (*what == fgetc(f))) {
         ++what;
       }
       if (*what == '\0') {
         fclose(f);
         return true;
       } else {
         what = search_string;
       }
     }
   }
   fclose(f);
 
   // Did not find string in the proc file.
   return false;
 }
+
+bool OS::ArmCpuHasFeature(CpuFeature feature) {
+  const int max_items = 2;
+  const char* search_strings[max_items] = { NULL, NULL };
+  int search_items = 0;
+  // Simple detection of VFP at runtime for Linux.
+  // It is based on /proc/cpuinfo, which reveals hardware configuration
+  // to user-space applications.  According to ARM (mid 2009), no similar
+  // facility is universally available on the ARM architectures,
+  // so it's up to individual OSes to provide such.
+  switch (feature) {
+    case VFP3:
+      search_strings[0] = "vfpv3";
+      // Some old kernels will report vfp for A8, not vfpv3, so we check for
+      // A8 explicitely. The cpuinfo file report the CPU Part which for Cortex
+      // A8 is 0xc08.
+      search_strings[1] = "0xc08";
+      search_items = 2;
+      ASSERT(search_items <= max_items);
+      break;
+    case ARMv7:
+      search_strings[0] = "ARMv7" ;
+      search_items = 1;
+      ASSERT(search_items <= max_items);
+      break;
+    default:
+      UNREACHABLE();
+  }
+
+  for (int i = 0; i < search_items; ++i) {
+    if (CPUInfoContainsString(search_strings[i])) {
+      return true;
+    }
+  }
+
+  return false;
+}
 #endif  // def __arm__
 
 
 int OS::ActivationFrameAlignment() {
 #ifdef V8_TARGET_ARCH_ARM
   // On EABI ARM targets this is required for fp correctness in the
   // runtime system.
   return 8;
 #elif V8_TARGET_ARCH_MIPS
   return 8;
@@ skipping 729 matching lines @@
   }
 
   // This sampler is no longer the active sampler.
   active_sampler_ = NULL;
 }
 
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 } }  // namespace v8::internal