diff options
Diffstat (limited to 'ArmPkg/Library/BaseMemoryLibStm/Arm/CopyMem.S')
-rwxr-xr-x | ArmPkg/Library/BaseMemoryLibStm/Arm/CopyMem.S | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/ArmPkg/Library/BaseMemoryLibStm/Arm/CopyMem.S b/ArmPkg/Library/BaseMemoryLibStm/Arm/CopyMem.S new file mode 100755 index 0000000000..91a4dfcfe5 --- /dev/null +++ b/ArmPkg/Library/BaseMemoryLibStm/Arm/CopyMem.S @@ -0,0 +1,112 @@ +#------------------------------------------------------------------------------
+#
+# CopyMem() worker for ARM
+#
+# This file started out as C code that did 64 bit moves if the buffer was
+# 32-bit aligned, else it does a byte copy. It also does a byte copy for
+# any trailing bytes. It was updated to do 32-byte copies using stm/ldm.
+#
+# Copyright (c) 2008-2010 Apple Inc. All rights reserved.<BR>
+# All rights reserved. This program and the accompanying materials
+# are licensed and made available under the terms and conditions of the BSD License
+# which accompanies this distribution. The full text of the license may be found at
+# http://opensource.org/licenses/bsd-license.php
+#
+# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+#
+#------------------------------------------------------------------------------
+
+/**
+ Copy Length bytes from Source to Destination. Overlap is OK.
+
+ This implementation
+
+ @param Destination Target of copy
+ @param Source Place to copy from
+ @param Length Number of bytes to copy
+
+ @return Destination
+
+
+VOID *
+EFIAPI
+InternalMemCopyMem (
+ OUT VOID *DestinationBuffer,
+ IN CONST VOID *SourceBuffer,
+ IN UINTN Length
+ )
+**/
+.text
+.align 2
+.globl ASM_PFX(InternalMemCopyMem)
+
+ASM_PFX(InternalMemCopyMem):
+ stmfd sp!, {r4-r11, lr}
+ tst r0, #3
+ mov r11, r0
+ mov r10, r0
+ mov ip, r2
+ mov lr, r1
+ movne r0, #0
+ bne L4
+ tst r1, #3
+ movne r3, #0
+ moveq r3, #1
+ cmp r2, #31
+ movls r0, #0
+ andhi r0, r3, #1
+L4:
+ cmp r11, r1
+ bcc L26
+ bls L7
+ rsb r3, r1, r11
+ cmp ip, r3
+ bcc L26
+ cmp ip, #0
+ beq L7
+ add r10, r11, ip
+ add lr, ip, r1
+ b L16
+L29:
+ sub ip, ip, #8
+ cmp ip, #7
+ ldrd r2, [lr, #-8]!
+ movls r0, #0
+ cmp ip, #0
+ strd r2, [r10, #-8]!
+ beq L7
+L16:
+ cmp r0, #0
+ bne L29
+ sub r3, lr, #1
+ sub ip, ip, #1
+ ldrb r3, [r3, #0]
+ sub r2, r10, #1
+ cmp ip, #0
+ sub r10, r10, #1
+ sub lr, lr, #1
+ strb r3, [r2, #0]
+ bne L16
+ b L7
+L11:
+ ldrb r3, [lr], #1
+ sub ip, ip, #1
+ strb r3, [r10], #1
+L26:
+ cmp ip, #0
+ beq L7
+L30:
+ cmp r0, #0
+ beq L11
+ sub ip, ip, #32
+ cmp ip, #31
+ ldmia lr!, {r2-r9}
+ movls r0, #0
+ cmp ip, #0
+ stmia r10!, {r2-r9}
+ bne L30
+L7:
+ mov r0, r11
+ ldmfd sp!, {r4-r11, pc}
+
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