implement Ivy Bridge RDRAND support

Signed-off-by: Steven Noonan <steven@uplinklabs.net>
tycho · Jun 19, 2012 · 8d7e1c8 · 8d7e1c8
1 parent 958b85e
commit 8d7e1c8
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diff --git a/src/rnd.c b/src/rnd.c
@@ -15,6 +15,20 @@ extern int NDECL(rand);
 # endif
 #endif /* LINT */
 
+#ifdef __RDRND__
+#include <immintrin.h>
+unsigned int rdrand()
+{
+	unsigned int x;
+	if (!_rdrand32_step(&x))
+		return rand();
+	else
+		return x;
+}
+#undef RND
+#define RND(x)  (int)(rdrand() % (long)(x))
+#endif
+
 #ifdef OVL0
 
 int

diff --git a/sys/unix/Makefile.src b/sys/unix/Makefile.src
@@ -184,6 +184,11 @@ endif
 
 LFLAGS = 
 
+ifeq ($(RNG),rdrand)
+CFLAGS += -mrdrnd
+LFLAGS += -mrdrnd
+endif
+
 # The Qt and Be window systems are written in C++, while the rest of
 # NetHack is standard C.  If using Qt, uncomment the LINK line here to get
 # the C++ libraries linked in.

diff --git a/sys/unix/Makefile.utl b/sys/unix/Makefile.utl
@@ -103,6 +103,11 @@ endif
 
 LFLAGS =
 
+ifeq ($(RNG),rdrand)
+CFLAGS += -mrdrnd
+LFLAGS += -mrdrnd
+endif
+
 LIBS =
 
 # If you are cross-compiling, you must use this: