MdePkg/BaseLib: Support IA32 processors without CMOVx

[mirror_edk2.git] / MdePkg / Library / BaseLib / Ia32 / RRotU64.S

diff --git a/MdePkg/Library/BaseLib/Ia32/RRotU64.S b/MdePkg/Library/BaseLib/Ia32/RRotU64.S
index 4b89a4eaa7aaf587a62c685e8cdc7d02be5dcbe6..f42f45018990b08fcfa6fde29cdc67c7a4e68363 100644 (file)
--- a/MdePkg/Library/BaseLib/Ia32/RRotU64.S
+++ b/MdePkg/Library/BaseLib/Ia32/RRotU64.S
@@ -1,17 +1,17 @@
 #------------------------------------------------------------------------------\r
 #\r
-# Copyright (c) 2006, Intel Corporation\r
-# All rights reserved. This program and the accompanying materials\r
+# Copyright (c) 2006 - 2015, 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
 #\r
 # Module Name:\r
 #\r
-#   RRotU64.asm\r
+#   RRotU64.S\r
 #\r
 # Abstract:\r
 #\r
@@ -19,7 +19,7 @@
 #\r
 #------------------------------------------------------------------------------\r
 \r
-.global _InternalMathRRotU64\r
+ASM_GLOBAL ASM_PFX(InternalMathRRotU64)\r
 \r
 #------------------------------------------------------------------------------\r
 # UINT64\r
@@ -29,7 +29,7 @@
 #   IN      UINTN                     Count\r
 #   );\r
 #------------------------------------------------------------------------------\r
-_InternalMathRRotU64:\r
+ASM_PFX(InternalMathRRotU64):\r
     push    %ebx\r
     movb    16(%esp), %cl\r
     movl    8(%esp), %eax\r
@@ -38,9 +38,11 @@ _InternalMathRRotU64:
     shrdl   %cl, %edx, %eax\r
     roll    %cl, %ebx\r
     shrdl   %cl, %ebx, %edx\r
-    testb   $32, %cl\r
-    cmovnz  %eax, %ecx\r
-    cmovnz  %edx, %eax\r
-    cmovnz  %ecx, %edx\r
+    testb   $32, %cl                    # Count >= 32?\r
+    jz      L0\r
+    movl    %eax, %ecx                  # switch eax & edx if Count >= 32\r
+    movl    %edx, %eax\r
+    movl    %ecx, %edx\r
+L0:    \r
     pop     %ebx\r
     ret\r