1 files changed, 61 insertions, 0 deletions
diff --git a/src/math/bigint/mp_msvc64/mp_asm.h b/src/math/bigint/mp_msvc64/mp_asm.h
new file mode 100644
index 000000000..8e4535c35
--- /dev/null
+++ b/src/math/bigint/mp_msvc64/mp_asm.h
@@ -0,0 +1,61 @@
+/*
+* Multiply-Add for 64-bit MSVC
+* (C) 2010 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#ifndef BOTAN_MP_ASM_H__
+#define BOTAN_MP_ASM_H__
+
+#include <botan/mp_types.h>
+#include <intrin.h>
+
+#if (BOTAN_MP_WORD_BITS != 64)
+   #error The mp_msvc64 module requires that BOTAN_MP_WORD_BITS == 64
+#endif
+
+#pragma intrinsic(_umul128)
+
+namespace Botan {
+
+extern "C" {
+
+/*
+* Word Multiply
+*/
+inline word word_madd2(word a, word b, word* c)
+   {
+   word hi, lo;
+   lo = _umul128(a, b, &hi);
+
+   lo += *c;
+   hi += (lo < *c); // carry?
+
+   *c = hi;
+   return lo;
+   }
+
+/*
+* Word Multiply/Add
+*/
+inline word word_madd3(word a, word b, word c, word* d)
+   {
+   word hi, lo;
+   lo = _umul128(a, b, &hi);
+
+   lo += c;
+   hi += (lo < c); // carry?
+
+   lo += *d;
+   hi += (lo < *d); // carry?
+
+   *d = hi;
+   return lo;
+   }
+
+}
+
+}
+
+#endif