Add '_xgetbv()' for MSVC-9 and earlier

1 files changed, 17 insertions, 0 deletions

diff --git a/libs/pbd/fpu.cc b/libs/pbd/fpu.cc
index 7b73c689c4..97e6ed59dd 100644
--- a/libs/pbd/fpu.cc
+++ b/libs/pbd/fpu.cc
@@ -95,6 +95,23 @@ _xgetbv (uint32_t xcr)
 #endif
 }
 
+#elif _MSC_VER < 1600
+
+// '_xgetbv()' was only available from VC10 onwards
+__declspec(noinline) static uint64_t
+_xgetbv (uint32_t xcr)
+{
+	return 0;
+
+	// N.B.  The following would probably work for a pre-VC10 build,
+	// although it might suffer from optimization issues.  We'd need
+	// to place this function into its own (unoptimized) source file.
+	__asm {   
+			 mov ecx, [xcr]
+			 __asm _emit 0x0f __asm _emit 0x01 __asm _emit 0xd0   /*xgetbv*/
+		  }
+}
+
 #endif /* !COMPILER_MSVC */
 #endif /* ARCH_X86 */