projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| 170f7936 JJ |
1 | ;------------------------------------------------------------------------------\r |
| 2 | ;\r | |
| 3 | ; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>\r | |
| 9344f092 | 4 | ; SPDX-License-Identifier: BSD-2-Clause-Patent\r |
| 170f7936 JJ |
5 | ;\r |
| 6 | ; Module Name:\r | |
| 7 | ;\r | |
| 8 | ; CopyMem.Asm\r | |
| 9 | ;\r | |
| 10 | ; Abstract:\r | |
| 11 | ;\r | |
| 12 | ; CopyMem function\r | |
| 13 | ;\r | |
| 14 | ; Notes:\r | |
| 15 | ;\r | |
| 16 | ;------------------------------------------------------------------------------\r | |
| 17 | \r | |
| 18 | SECTION .text\r | |
| 19 | \r | |
| 20 | ;------------------------------------------------------------------------------\r | |
| 21 | ; VOID *\r | |
| 22 | ; InternalMemCopyMem (\r | |
| 23 | ; IN VOID *Destination,\r | |
| 24 | ; IN VOID *Source,\r | |
| 25 | ; IN UINTN Count\r | |
| 26 | ; )\r | |
| 27 | ;------------------------------------------------------------------------------\r | |
| 28 | global ASM_PFX(InternalMemCopyMem)\r | |
| 29 | ASM_PFX(InternalMemCopyMem):\r | |
| 30 | push esi\r | |
| 31 | push edi\r | |
| 32 | mov esi, [esp + 16] ; esi <- Source\r | |
| 33 | mov edi, [esp + 12] ; edi <- Destination\r | |
| 34 | mov edx, [esp + 20] ; edx <- Count\r | |
| 35 | lea eax, [esi + edx - 1] ; eax <- End of Source\r | |
| 36 | cmp esi, edi\r | |
| 37 | jae .0\r | |
| 38 | cmp eax, edi\r | |
| 39 | jae @CopyBackward ; Copy backward if overlapped\r | |
| 40 | .0:\r | |
| 41 | mov ecx, edx\r | |
| 42 | and edx, 3\r | |
| 43 | shr ecx, 2\r | |
| 44 | rep movsd ; Copy as many Dwords as possible\r | |
| 45 | jmp @CopyBytes\r | |
| 46 | @CopyBackward:\r | |
| 47 | mov esi, eax ; esi <- End of Source\r | |
| 48 | lea edi, [edi + edx - 1] ; edi <- End of Destination\r | |
| 49 | std\r | |
| 50 | @CopyBytes:\r | |
| 51 | mov ecx, edx\r | |
| 52 | rep movsb ; Copy bytes backward\r | |
| 53 | cld\r | |
| 54 | mov eax, [esp + 12] ; eax <- Destination as return value\r | |
| 55 | pop edi\r | |
| 56 | pop esi\r | |
| 57 | ret\r | |
| 58 | \r |