1 #------------------------------------------------------------------------------ 2 # 3 # CopyMem() worker for ARM 4 # 5 # This file started out as C code that did 64 bit moves if the buffer was 6 # 32-bit aligned, else it does a byte copy. It also does a byte copy for 7 # any trailing bytes. Update using VSTM/SLDM to do 128 byte copies. 8 # 9 # Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR> 10 # This program and the accompanying materials 11 # are licensed and made available under the terms and conditions of the BSD License 12 # which accompanies this distribution. The full text of the license may be found at 13 # http://opensource.org/licenses/bsd-license.php 14 # 15 # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 16 # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 17 # 18 #------------------------------------------------------------------------------ 19 20 /** 21 Copy Length bytes from Source to Destination. Overlap is OK. 22 23 This implementation 24 25 @param Destination Target of copy 26 @param Source Place to copy from 27 @param Length Number of bytes to copy 28 29 @return Destination 30 31 32 VOID * 33 EFIAPI 34 InternalMemCopyMem ( 35 OUT VOID *DestinationBuffer, 36 IN CONST VOID *SourceBuffer, 37 IN UINTN Length 38 ) 39 **/ 40 .text 41 .align 2 42 GCC_ASM_EXPORT(InternalMemCopyMem) 43 44 ASM_PFX(InternalMemCopyMem): 45 stmfd sp!, {r4, r9, lr} 46 tst r0, #3 47 mov r4, r0 48 mov r9, r0 49 mov ip, r2 50 mov lr, r1 51 movne r0, #0 52 bne L4 53 tst r1, #3 54 movne r3, #0 55 moveq r3, #1 56 cmp r2, #127 57 movls r0, #0 58 andhi r0, r3, #1 59 L4: 60 cmp r4, r1 61 bcc L26 62 bls L7 63 rsb r3, r1, r4 64 cmp ip, r3 65 bcc L26 66 cmp ip, #0 67 beq L7 68 add r9, r4, ip 69 add lr, ip, r1 70 b L16 71 L29: 72 sub ip, ip, #8 73 cmp ip, #7 74 ldrd r2, [lr, #-8]! 75 movls r0, #0 76 cmp ip, #0 77 strd r2, [r9, #-8]! 78 beq L7 79 L16: 80 cmp r0, #0 81 bne L29 82 sub r3, lr, #1 83 sub ip, ip, #1 84 ldrb r3, [r3, #0] 85 sub r2, r9, #1 86 cmp ip, #0 87 sub r9, r9, #1 88 sub lr, lr, #1 89 strb r3, [r2, #0] 90 bne L16 91 b L7 92 L11: 93 ldrb r3, [lr], #1 94 sub ip, ip, #1 95 strb r3, [r9], #1 96 L26: 97 cmp ip, #0 98 beq L7 99 L30: 100 cmp r0, #0 101 beq L11 102 sub ip, ip, #128 // 32 103 cmp ip, #127 // 31 104 vldm lr!, {d0-d15} 105 movls r0, #0 106 cmp ip, #0 107 vstm r9!, {d0-d15} 108 bne L30 109 L7: 110 dsb 111 mov r0, r4 112 ldmfd sp!, {r4, r9, pc} 113 114 115
