[PATCH v4 3/7] CryptoPkg/IntrinsicLib: Fix possible unresolved external symbol issue

["Xiaoyu lu" <xiaoyux.lu@intel.com>]

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1089

This is for the upcoming upgrade to OpenSSL_1_1_1b

Compiler optimization(Visual Studio) may automatically use _ftol2
instead of some type conversion. For example:

 OpensslLib.lib(drbg_lib.obj) : error LNK2001:
    unresolved external symbol __ftol2

This patch add _ftol2 function for the compiler intrinsic.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Ting Ye <ting.ye@intel.com>
Signed-off-by: Xiaoyu Lu <xiaoyux.lu@intel.com>
---
 CryptoPkg/Library/IntrinsicLib/IntrinsicLib.inf |  4 +++-
 CryptoPkg/Library/IntrinsicLib/Ia32/MathFtol.c  | 22 ++++++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 CryptoPkg/Library/IntrinsicLib/Ia32/MathFtol.c

diff --git a/CryptoPkg/Library/IntrinsicLib/IntrinsicLib.inf b/CryptoPkg/Library/IntrinsicLib/IntrinsicLib.inf
index 5a20967b6cb8..fcbb93316cf7 100644
--- a/CryptoPkg/Library/IntrinsicLib/IntrinsicLib.inf
+++ b/CryptoPkg/Library/IntrinsicLib/IntrinsicLib.inf
@@ -1,7 +1,7 @@
 ## @file
 #  Intrinsic Routines Wrapper Library Instance.
 #
-#  Copyright (c) 2010 - 2018, Intel Corporation. All rights reserved.<BR>
+#  Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
 #  SPDX-License-Identifier: BSD-2-Clause-Patent
 #
 ##
@@ -29,9 +29,11 @@ [Sources.IA32]
 
   Ia32/MathLShiftS64.c      | MSFT
   Ia32/MathRShiftU64.c      | MSFT
+  Ia32/MathFtol.c           | MSFT
 
   Ia32/MathLShiftS64.c      | INTEL
   Ia32/MathRShiftU64.c      | INTEL
+  Ia32/MathFtol.c           | INTEL
 
   Ia32/MathLShiftS64.nasm   | GCC
   Ia32/MathRShiftU64.nasm   | GCC
diff --git a/CryptoPkg/Library/IntrinsicLib/Ia32/MathFtol.c b/CryptoPkg/Library/IntrinsicLib/Ia32/MathFtol.c
new file mode 100644
index 000000000000..147a19a4adb0
--- /dev/null
+++ b/CryptoPkg/Library/IntrinsicLib/Ia32/MathFtol.c
@@ -0,0 +1,22 @@
+/** @file
+  64-bit Math Worker Function.
+  The 32-bit versions of C compiler generate calls to library routines
+  to handle 64-bit math. These functions use non-standard calling conventions.
+
+Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+/*
+ * Floating point to integer conversion.
+ */
+__declspec(naked) void _ftol2 (void)
+{
+  _asm {
+    fistp qword ptr [esp-8]
+    mov   edx, [esp-4]
+    mov   eax, [esp-8]
+    ret
+  }
+}
-- 
2.7.4