MdePkg/BaseMemoryLib: widen aligned accesses to 32 or 64 bits

[mirror_edk2.git] / MdePkg / Library / BaseMemoryLib / CopyMem.c

diff --git a/MdePkg/Library/BaseMemoryLib/CopyMem.c b/MdePkg/Library/BaseMemoryLib/CopyMem.c
index 37f03660df5f6870c9e6126325f547be87a5e72f..6f4fd900df5d2e50729f27115646a8ea3cd789cb 100644 (file)
--- a/MdePkg/Library/BaseMemoryLib/CopyMem.c
+++ b/MdePkg/Library/BaseMemoryLib/CopyMem.c
@@ -4,6 +4,9 @@
   particular platform easily if an optimized version is desired.\r
 \r
   Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>\r
+  Copyright (c) 2012 - 2013, ARM Ltd. All rights reserved.<BR>\r
+  Copyright (c) 2016, Linaro Ltd. All rights reserved.<BR>\r
+\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
@@ -44,18 +47,107 @@ InternalMemCopyMem (
   //\r
   volatile UINT8                    *Destination8;\r
   CONST UINT8                       *Source8;\r
+  volatile UINT32                   *Destination32;\r
+  CONST UINT32                      *Source32;\r
+  volatile UINT64                   *Destination64;\r
+  CONST UINT64                      *Source64;\r
+  UINTN                             Alignment;\r
+\r
+  if ((((UINTN)DestinationBuffer & 0x7) == 0) && (((UINTN)SourceBuffer & 0x7) == 0) && (Length >= 8)) {\r
+    if (SourceBuffer > DestinationBuffer) {\r
+      Destination64 = (UINT64*)DestinationBuffer;\r
+      Source64 = (CONST UINT64*)SourceBuffer;\r
+      while (Length >= 8) {\r
+        *(Destination64++) = *(Source64++);\r
+        Length -= 8;\r
+      }\r
+\r
+      // Finish if there are still some bytes to copy\r
+      Destination8 = (UINT8*)Destination64;\r
+      Source8 = (CONST UINT8*)Source64;\r
+      while (Length-- != 0) {\r
+        *(Destination8++) = *(Source8++);\r
+      }\r
+    } else if (SourceBuffer < DestinationBuffer) {\r
+      Destination64 = (UINT64*)((UINTN)DestinationBuffer + Length);\r
+      Source64 = (CONST UINT64*)((UINTN)SourceBuffer + Length);\r
+\r
+      // Destination64 and Source64 were aligned on a 64-bit boundary\r
+      // but if length is not a multiple of 8 bytes then they won't be\r
+      // anymore.\r
+\r
+      Alignment = Length & 0x7;\r
+      if (Alignment != 0) {\r
+        Destination8 = (UINT8*)Destination64;\r
+        Source8 = (CONST UINT8*)Source64;\r
+\r
+        while (Alignment-- != 0) {\r
+          *(--Destination8) = *(--Source8);\r
+          --Length;\r
+        }\r
+        Destination64 = (UINT64*)Destination8;\r
+        Source64 = (CONST UINT64*)Source8;\r
+      }\r
+\r
+      while (Length > 0) {\r
+        *(--Destination64) = *(--Source64);\r
+        Length -= 8;\r
+      }\r
+    }\r
+  } else if ((((UINTN)DestinationBuffer & 0x3) == 0) && (((UINTN)SourceBuffer & 0x3) == 0) && (Length >= 4)) {\r
+    if (SourceBuffer > DestinationBuffer) {\r
+      Destination32 = (UINT32*)DestinationBuffer;\r
+      Source32 = (CONST UINT32*)SourceBuffer;\r
+      while (Length >= 4) {\r
+        *(Destination32++) = *(Source32++);\r
+        Length -= 4;\r
+      }\r
+\r
+      // Finish if there are still some bytes to copy\r
+      Destination8 = (UINT8*)Destination32;\r
+      Source8 = (CONST UINT8*)Source32;\r
+      while (Length-- != 0) {\r
+        *(Destination8++) = *(Source8++);\r
+      }\r
+    } else if (SourceBuffer < DestinationBuffer) {\r
+      Destination32 = (UINT32*)((UINTN)DestinationBuffer + Length);\r
+      Source32 = (CONST UINT32*)((UINTN)SourceBuffer + Length);\r
+\r
+      // Destination32 and Source32 were aligned on a 32-bit boundary\r
+      // but if length is not a multiple of 4 bytes then they won't be\r
+      // anymore.\r
+\r
+      Alignment = Length & 0x3;\r
+      if (Alignment != 0) {\r
+        Destination8 = (UINT8*)Destination32;\r
+        Source8 = (CONST UINT8*)Source32;\r
+\r
+        while (Alignment-- != 0) {\r
+          *(--Destination8) = *(--Source8);\r
+          --Length;\r
+        }\r
+        Destination32 = (UINT32*)Destination8;\r
+        Source32 = (CONST UINT32*)Source8;\r
+      }\r
 \r
-  if (SourceBuffer > DestinationBuffer) {\r
-    Destination8 = (UINT8*)DestinationBuffer;\r
-    Source8 = (CONST UINT8*)SourceBuffer;\r
-    while (Length-- != 0) {\r
-      *(Destination8++) = *(Source8++);\r
+      while (Length > 0) {\r
+        *(--Destination32) = *(--Source32);\r
+        Length -= 4;\r
+      }\r
     }\r
-  } else if (SourceBuffer < DestinationBuffer) {\r
-    Destination8 = (UINT8*)DestinationBuffer + Length;\r
-    Source8 = (CONST UINT8*)SourceBuffer + Length;\r
-    while (Length-- != 0) {\r
-      *(--Destination8) = *(--Source8);\r
+  } else {\r
+    if (SourceBuffer > DestinationBuffer) {\r
+      Destination8 = (UINT8*)DestinationBuffer;\r
+      Source8 = (CONST UINT8*)SourceBuffer;\r
+      while (Length-- != 0) {\r
+        *(Destination8++) = *(Source8++);\r
+      }\r
+    } else if (SourceBuffer < DestinationBuffer) {\r
+      Destination8 = (UINT8*)DestinationBuffer + Length;\r
+      Source8 = (CONST UINT8*)SourceBuffer + Length;\r
+      while (Length-- != 0) {\r
+        *(--Destination8) = *(--Source8);\r
+      }\r
     }\r
   }\r
   return DestinationBuffer;\r