projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| a72cc2b2 | 1 | /* Optimized strcpy implementation for PowerPC476. |
| 568035b7 | 2 | Copyright (C) 2010-2013 Free Software Foundation, Inc. |
| a72cc2b2 LM |
3 | This file is part of the GNU C Library. |
| 4 | ||
| 5 | The GNU C Library is free software; you can redistribute it and/or | |
| 6 | modify it under the terms of the GNU Lesser General Public | |
| 7 | License as published by the Free Software Foundation; either | |
| 8 | version 2.1 of the License, or (at your option) any later version. | |
| 9 | ||
| 10 | The GNU C Library is distributed in the hope that it will be useful, | |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 | Lesser General Public License for more details. | |
| 14 | ||
| 15 | You should have received a copy of the GNU Lesser General Public | |
| ab84e3ff PE |
16 | License along with the GNU C Library. If not, see |
| 17 | <http://www.gnu.org/licenses/>. */ | |
| a72cc2b2 LM |
18 | |
| 19 | #include <sysdep.h> | |
| 20 | #include <bp-sym.h> | |
| 21 | #include <bp-asm.h> | |
| 22 | ||
| 23 | /* strcpy | |
| 24 | ||
| 25 | Register Use | |
| 26 | r3:destination and return address | |
| 27 | r4:source address | |
| 28 | r10:temp destination address | |
| 29 | ||
| 30 | Implementation description | |
| 31 | Loop by checking 2 words at a time, with dlmzb. Check if there is a null | |
| 32 | in the 2 words. If there is a null jump to end checking to determine | |
| 33 | where in the last 8 bytes it is. Copy the appropriate bytes of the last | |
| 34 | 8 according to the null position. */ | |
| 35 | ||
| 36 | EALIGN (BP_SYM (strcpy), 5, 0) | |
| 37 | neg r7,r4 | |
| 38 | subi r4,r4,1 | |
| 39 | clrlwi. r8,r7,29 | |
| 40 | subi r10,r3,1 | |
| 41 | beq L(pre_word8_loop) | |
| 42 | mtctr r8 | |
| 43 | ||
| 44 | L(loop): | |
| 45 | lbzu r5,0x01(r4) | |
| 46 | cmpi cr5,r5,0x0 | |
| 47 | stbu r5,0x01(r10) | |
| 48 | beq cr5,L(end_strcpy) | |
| 49 | bdnz L(loop) | |
| 50 | ||
| 51 | L(pre_word8_loop): | |
| 52 | subi r4,r4,3 | |
| 53 | subi r10,r10,3 | |
| 54 | ||
| 55 | L(word8_loop): | |
| 56 | lwzu r5,0x04(r4) | |
| 57 | lwzu r6,0x04(r4) | |
| 58 | dlmzb. r11,r5,r6 | |
| 59 | bne L(byte_copy) | |
| 60 | stwu r5,0x04(r10) | |
| 61 | stwu r6,0x04(r10) | |
| 62 | lwzu r5,0x04(r4) | |
| 63 | lwzu r6,0x04(r4) | |
| 64 | dlmzb. r11,r5,r6 | |
| 65 | bne L(byte_copy) | |
| 66 | stwu r5,0x04(r10) | |
| 67 | stwu r6,0x04(r10) | |
| 68 | lwzu r5,0x04(r4) | |
| 69 | lwzu r6,0x04(r4) | |
| 70 | dlmzb. r11,r5,r6 | |
| 71 | bne L(byte_copy) | |
| 72 | stwu r5,0x04(r10) | |
| 73 | stwu r6,0x04(r10) | |
| 74 | lwzu r5,0x04(r4) | |
| 75 | lwzu r6,0x04(r4) | |
| 76 | dlmzb. r11,r5,r6 | |
| 77 | bne L(byte_copy) | |
| 78 | stwu r5,0x04(r10) | |
| 79 | stwu r6,0x04(r10) | |
| 80 | b L(word8_loop) | |
| 81 | ||
| 82 | L(last_bytes_copy): | |
| 83 | stwu r5,0x04(r10) | |
| 84 | subi r11,r11,4 | |
| 85 | mtctr r11 | |
| 86 | addi r10,r10,3 | |
| 87 | subi r4,r4,1 | |
| 88 | ||
| 89 | L(last_bytes_copy_loop): | |
| 90 | lbzu r5,0x01(r4) | |
| 91 | stbu r5,0x01(r10) | |
| 92 | bdnz L(last_bytes_copy_loop) | |
| 93 | blr | |
| 94 | ||
| 95 | L(byte_copy): | |
| 96 | blt L(last_bytes_copy) | |
| 97 | mtctr r11 | |
| 98 | addi r10,r10,3 | |
| 99 | subi r4,r4,5 | |
| 100 | ||
| 101 | L(last_bytes_copy_loop2): | |
| 102 | lbzu r5,0x01(r4) | |
| 103 | stbu r5,0x01(r10) | |
| 104 | bdnz L(last_bytes_copy_loop2) | |
| 105 | ||
| 106 | L(end_strcpy): | |
| 107 | blr | |
| 108 | END (BP_SYM (strcpy)) | |
| 109 | libc_hidden_builtin_def (strcpy) |