Modify CPUID so all the check functions are purely inline. Add a new

initialize() call which must be called prior to use of any other
functions.

4 files changed, 32 insertions, 49 deletions

diff --git a/doc/examples/cpuid.cpp b/doc/examples/cpuid.cpp
index f4d441ba2..059cfdbc0 100644
--- a/doc/examples/cpuid.cpp
+++ b/doc/examples/cpuid.cpp
@@ -14,15 +14,17 @@ namespace {
 void print_if_feature(const std::string& feature_name, bool exists)
    {
    if(exists)
-      std::cout << feature_name << '\n';
+      std::cout << "Y: " << feature_name << "\n";
    else
-      std::cout << '[' << feature_name << ']' << '\n';
+      std::cout << "N: " << feature_name << "\n";
    }
 
 }
 
 int main()
    {
+   CPUID::initialize();
+
    std::cout << "Cache line size = " << CPUID::cache_line_size() << "\n";
 
    print_if_feature("RDTSC", CPUID::has_rdtsc());
diff --git a/src/libstate/libstate.cpp b/src/libstate/libstate.cpp
index 83fb31406..1db9ca44c 100644
--- a/src/libstate/libstate.cpp
+++ b/src/libstate/libstate.cpp
@@ -8,6 +8,7 @@
 #include <botan/libstate.h>
 #include <botan/charset.h>
 #include <botan/engine.h>
+#include <botan/cpuid.h>
 #include <botan/internal/defalloc.h>
 #include <botan/internal/default_engine.h>
 #include <botan/internal/mutex.h>
@@ -241,6 +242,8 @@ RandomNumberGenerator& Library_State::global_rng()
 */
 void Library_State::initialize(bool thread_safe)
    {
+   CPUID::initialize();
+
    if(mutex_factory)
       throw Invalid_State("Library_State has already been initialized");
 
diff --git a/src/utils/cpuid.cpp b/src/utils/cpuid.cpp
index 4837e7ac4..b76210865 100644
--- a/src/utils/cpuid.cpp
+++ b/src/utils/cpuid.cpp
@@ -1,6 +1,6 @@
 /*
 * Runtime CPU detection
-* (C) 2009 Jack Lloyd
+* (C) 2009-2010 Jack Lloyd
 *
 * Distributed under the terms of the Botan license
 */
@@ -47,6 +47,10 @@
 
 namespace Botan {
 
+u64bit CPUID::x86_processor_flags = 0;
+u32bit CPUID::cache_line = 32;
+bool CPUID::altivec_capable = false;
+
 namespace {
 
 u32bit get_x86_cache_line_size()
@@ -140,54 +144,21 @@ bool altivec_check_pvr_emul()
 
 }
 
-/*
-* Call the x86 CPUID instruction and return the contents of ecx and
-* edx, which contain the feature masks.
-*/
-u64bit CPUID::x86_processor_flags()
+void CPUID::initialize()
    {
-   static u64bit proc_flags = 0;
-
-   if(proc_flags)
-      return proc_flags;
-
    u32bit cpuid[4] = { 0 };
    CALL_CPUID(1, cpuid);
 
-   // Set the FPU bit on to force caching in proc_flags
-   proc_flags = ((u64bit)cpuid[2] << 32) | cpuid[3] | 1;
-
-   return proc_flags;
-   }
-
-u32bit CPUID::cache_line_size()
-   {
-   static u32bit cl_size = 0;
-
-   if(cl_size)
-      return cl_size;
+   x86_processor_flags = ((u64bit)cpuid[2] << 32) | cpuid[3];
 
-   cl_size = get_x86_cache_line_size();
+   cache_line = get_x86_cache_line_size();
 
-   return cl_size;
-   }
+   altivec_capable = false;
 
-bool CPUID::has_altivec()
-   {
-   static bool first_time = true;
-   static bool altivec_capable = false;
-
-   if(first_time)
-      {
 #if defined(BOTAN_TARGET_CPU_IS_PPC_FAMILY)
       if(altivec_check_sysctl() || altivec_check_pvr_emul())
          altivec_capable = true;
 #endif
-
-      first_time = false;
-      }
-
-   return altivec_capable;
    }
 
 }
diff --git a/src/utils/cpuid.h b/src/utils/cpuid.h
index a6a278a6e..6339a0117 100644
--- a/src/utils/cpuid.h
+++ b/src/utils/cpuid.h
@@ -1,6 +1,6 @@
 /*
 * Runtime CPU detection
-* (C) 2009 Jack Lloyd
+* (C) 2009-2010 Jack Lloyd
 *
 * Distributed under the terms of the Botan license
 */
@@ -19,9 +19,14 @@ class BOTAN_DLL CPUID
    {
    public:
       /**
+      * Probe the CPU and see what extensions are supported
+      */
+      static void initialize();
+
+      /**
       * Return a best guess of the cache line size
       */
-      static u32bit cache_line_size();
+      static u32bit cache_line_size() { return cache_line; }
 
       /**
       * Check if the processor supports RDTSC
@@ -68,13 +73,8 @@ class BOTAN_DLL CPUID
       /**
       * Check if the processor supports AltiVec/VMX
       */
-      static bool has_altivec();
+      static bool has_altivec() { return altivec_capable; }
    private:
-      static bool x86_processor_flags_has(u64bit bit)
-         {
-         return ((x86_processor_flags() >> bit) & 1);
-         }
-
       enum CPUID_bits {
          CPUID_RDTSC_BIT = 4,
          CPUID_SSE2_BIT = 26,
@@ -85,7 +85,14 @@ class BOTAN_DLL CPUID
          CPUID_AVX_BIT = 60
       };
 
-      static u64bit x86_processor_flags();
+      static bool x86_processor_flags_has(u64bit bit)
+         {
+         return ((x86_processor_flags >> bit) & 1);
+         }
+
+      static u64bit x86_processor_flags;
+      static u32bit cache_line;
+      static bool altivec_capable;
    };
 
 }