MdePkg/BaseLib: Support IA32 processors without CLFLUSH

[mirror_edk2.git] / MdePkg / Library / BaseLib / Ia32 / RShiftU64.asm

diff --git a/MdePkg/Library/BaseLib/Ia32/RShiftU64.asm b/MdePkg/Library/BaseLib/Ia32/RShiftU64.asm
index effbc55e1cab7a90eeea75bd090bd61db3f7aa6a..2fe60572ee99c6abcfb691bca2adc03c3396cbeb 100644 (file)
--- a/MdePkg/Library/BaseLib/Ia32/RShiftU64.asm
+++ b/MdePkg/Library/BaseLib/Ia32/RShiftU64.asm
@@ -1,10 +1,10 @@
 ;------------------------------------------------------------------------------\r
 ;\r
-; Copyright (c) 2006, Intel Corporation\r
-; All rights reserved. This program and the accompanying materials\r
+; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>\r
+; This program and the accompanying materials\r
 ; are licensed and made available under the terms and conditions of the BSD License\r
 ; which accompanies this distribution.  The full text of the license may be found at\r
-; http://opensource.org/licenses/bsd-license.php\r
+; http://opensource.org/licenses/bsd-license.php.\r
 ;\r
 ; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
 ; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
@@ -23,11 +23,19 @@
     .model  flat,C\r
     .code\r
 \r
+;------------------------------------------------------------------------------\r
+; UINT64\r
+; EFIAPI\r
+; InternalMathRShiftU64 (\r
+;   IN      UINT64                    Operand,\r
+;   IN      UINTN                     Count\r
+;   );\r
+;------------------------------------------------------------------------------\r
 InternalMathRShiftU64   PROC\r
-    mov     cl, [esp + 12]\r
+    mov     cl, [esp + 12]              ; cl <- Count\r
     xor     edx, edx\r
     mov     eax, [esp + 8]\r
-    test    cl, 32\r
+    test    cl, 32                      ; Count >= 32?\r
     cmovz   edx, eax\r
     cmovz   eax, [esp + 4]\r
     shrd    eax, edx, cl\r
@@ -35,4 +43,4 @@ InternalMathRShiftU64   PROC
     ret\r
 InternalMathRShiftU64   ENDP\r
 \r
-    END
\ No newline at end of file
+    END\r