1 files changed, 48 insertions, 0 deletions
diff --git a/src/VBox/Devices/EFI/Firmware/CryptoPkg/Library/IntrinsicLib/Ia32/MathLShiftS64.c b/src/VBox/Devices/EFI/Firmware/CryptoPkg/Library/IntrinsicLib/Ia32/MathLShiftS64.c
new file mode 100644
index 00000000..3b1255db
--- /dev/null
+++ b/src/VBox/Devices/EFI/Firmware/CryptoPkg/Library/IntrinsicLib/Ia32/MathLShiftS64.c
@@ -0,0 +1,48 @@
+/** @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) 2014, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+
+/*
+ * Shifts a 64-bit signed value left by a particular number of bits.
+ */
+__declspec(naked) void __cdecl _allshl (void)
+{
+  _asm {
+    ;
+    ; Handle shifting of 64 or more bits (return 0)
+    ;
+    cmp     cl, 64
+    jae     short ReturnZero
+
+    ;
+    ; Handle shifting of between 0 and 31 bits
+    ;
+    cmp     cl, 32
+    jae     short More32
+    shld    edx, eax, cl
+    shl     eax, cl
+    ret
+
+    ;
+    ; Handle shifting of between 32 and 63 bits
+    ;
+More32:
+    mov     edx, eax
+    xor     eax, eax
+    and     cl, 31
+    shl     edx, cl
+    ret
+
+ReturnZero:
+    xor     eax,eax
+    xor     edx,edx
+    ret
+  }
+}