projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| c891b2df | 1 | /* bcopy -- copy a block from source to destination. S/390 version. |
| 847b055c | 2 | This file is part of the GNU C Library. |
| b168057a | 3 | Copyright (C) 2000-2015 Free Software Foundation, Inc. |
| 847b055c AJ |
4 | Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com). |
| 5 | ||
| 41bdb6e2 AJ |
6 | The GNU C Library is free software; you can redistribute it and/or |
| 7 | modify it under the terms of the GNU Lesser General Public | |
| 8 | License as published by the Free Software Foundation; either | |
| 9 | version 2.1 of the License, or (at your option) any later version. | |
| 847b055c AJ |
10 | |
| 11 | The GNU C Library is distributed in the hope that it will be useful, | |
| 41bdb6e2 | 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 847b055c | 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 41bdb6e2 | 14 | Lesser General Public License for more details. |
| 847b055c | 15 | |
| 41bdb6e2 | 16 | You should have received a copy of the GNU Lesser General Public |
| 59ba27a6 PE |
17 | License along with the GNU C Library; if not, see |
| 18 | <http://www.gnu.org/licenses/>. */ | |
| 847b055c | 19 | |
| c891b2df UD |
20 | /* INPUT PARAMETERS |
| 21 | %r2 = address of source | |
| 22 | %r3 = address of destination | |
| 23 | %r4 = number of bytes to copy. */ | |
| 847b055c AJ |
24 | |
| 25 | #include "sysdep.h" | |
| 26 | #include "asm-syntax.h" | |
| 27 | ||
| 28 | .text | |
| 29 | ENTRY(__bcopy) | |
| c891b2df UD |
30 | ltr %r1,%r4 # zero bcopy ? |
| 31 | jz .L4 | |
| 847b055c AJ |
32 | clr %r2,%r3 # check against destructive overlap |
| 33 | jnl .L0 | |
| c891b2df | 34 | alr %r1,%r2 |
| 847b055c | 35 | clr %r1,%r3 |
| 3c204435 | 36 | jh .L7 |
| c891b2df UD |
37 | .L0: ahi %r4,-1 # length - 1 |
| 38 | lr %r1,%r4 | |
| 39 | srl %r1,8 | |
| 3c204435 | 40 | ltr %r1,%r1 # < 256 bytes to move ? |
| c891b2df | 41 | jz .L2 |
| 3c204435 UD |
42 | chi %r1,255 # > 1MB to move ? |
| 43 | jh .L5 | |
| c891b2df UD |
44 | .L1: mvc 0(256,%r3),0(%r2) # move in 256 byte chunks |
| 45 | la %r2,256(%r2) | |
| 46 | la %r3,256(%r3) | |
| 47 | brct %r1,.L1 | |
| 48 | .L2: bras %r1,.L3 # setup base pointer for execute | |
| 49 | mvc 0(1,%r3),0(%r2) # instruction for execute | |
| 50 | .L3: ex %r4,0(%r1) # execute mvc with length ((%r4)&255)+1 | |
| 51 | .L4: br %r14 | |
| 52 | ||
| 3c204435 UD |
53 | # data copies > 1MB are faster with mvcle. |
| 54 | .L5: ahi %r4,1 # length + 1 | |
| 55 | lr %r5,%r4 # source length | |
| 56 | lr %r4,%r2 # source address | |
| 57 | lr %r2,%r3 # set destination | |
| 58 | lr %r3,%r5 # destination length = source length | |
| 59 | .L6: mvcle %r2,%r4,0 # thats it, MVCLE is your friend | |
| 60 | jo .L6 | |
| 61 | br %r14 | |
| 62 | .L7: # destructive overlay, can not use mvcle | |
| 847b055c AJ |
63 | lr %r1,%r2 # bcopy is called with source,dest |
| 64 | lr %r2,%r3 # memmove with dest,source! Oh, well... | |
| 65 | lr %r3,%r1 | |
| 66 | basr %r1,0 | |
| 3c204435 | 67 | .L8: |
| 847b055c | 68 | #ifdef PIC |
| 3c204435 | 69 | al %r1,.L9-.L8(%r1) # get address of global offset table |
| 847b055c | 70 | # load address of memmove |
| 2581b98e | 71 | l %r1,memmove@GOT(%r1) |
| 847b055c | 72 | br %r1 |
| 3c204435 | 73 | .L9: .long _GLOBAL_OFFSET_TABLE_-.L8 |
| 847b055c | 74 | #else |
| 3c204435 | 75 | al %r1,.L9-.L8(%r1) # load address of memmove |
| 847b055c | 76 | br %r1 # jump to memmove |
| 3c204435 | 77 | .L9: .long memmove-.L8 |
| 847b055c AJ |
78 | #endif |
| 79 | ||
| 80 | END(__bcopy) | |
| 81 | ||
| 82 | #ifndef NO_WEAK_ALIAS | |
| 83 | weak_alias (__bcopy, bcopy) | |
| 84 | #endif | |
| c891b2df | 85 |