projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| 650425ce | 1 | /* Optimized strcpy implementation for PowerPC. |
| 4e141d64 | 2 | Copyright (C) 1997, 1999, 2000 Free Software Foundation, Inc. |
| 650425ce UD |
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 Library General Public License as | |
| 7 | published by the Free Software Foundation; either version 2 of the | |
| 8 | 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 | Library General Public License for more details. | |
| 14 | ||
| 15 | You should have received a copy of the GNU Library General Public | |
| 16 | License along with the GNU C Library; see the file COPYING.LIB. If not, | |
| 17 | write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
| 18 | Boston, MA 02111-1307, USA. */ | |
| 19 | ||
| 20 | #include <sysdep.h> | |
| 21 | ||
| 22 | /* See strlen.s for comments on how the end-of-string testing works. */ | |
| 23 | ||
| 650425ce UD |
24 | /* char * [r3] strcpy (char *dest [r3], const char *src [r4]) */ |
| 25 | ||
| 1d280d9f | 26 | EALIGN(strcpy, 4, 0) |
| 650425ce | 27 | |
| 1d280d9f GM |
28 | #define rTMP r0 |
| 29 | #define rRTN r3 /* incoming DEST arg preserved as result */ | |
| 30 | #define rSRC r4 /* pointer to previous word in src */ | |
| 31 | #define rDEST r5 /* pointer to previous word in dest */ | |
| 32 | #define rWORD r6 /* current word from src */ | |
| 33 | #define rFEFE r7 /* constant 0xfefefeff (-0x01010101) */ | |
| 34 | #define r7F7F r8 /* constant 0x7f7f7f7f */ | |
| 35 | #define rNEG r9 /* ~(word in s1 | 0x7f7f7f7f) */ | |
| 36 | #define rALT r10 /* alternate word from src */ | |
| 650425ce | 37 | |
| 1d280d9f GM |
38 | or rTMP, rSRC, rRTN |
| 39 | clrlwi. rTMP, rTMP, 30 | |
| 40 | addi rDEST, rRTN, -4 | |
| 41 | bne L(unaligned) | |
| 650425ce | 42 | |
| 1d280d9f GM |
43 | lis rFEFE, -0x101 |
| 44 | lis r7F7F, 0x7f7f | |
| 45 | lwz rWORD, 0(rSRC) | |
| 46 | addi rFEFE, rFEFE, -0x101 | |
| 47 | addi r7F7F, r7F7F, 0x7f7f | |
| 48 | b L(g2) | |
| 650425ce | 49 | |
| 1d280d9f GM |
50 | L(g0): lwzu rALT, 4(rSRC) |
| 51 | stwu rWORD, 4(rDEST) | |
| 52 | add rTMP, rFEFE, rALT | |
| 53 | nor rNEG, r7F7F, rALT | |
| 54 | and. rTMP, rTMP, rNEG | |
| 55 | bne- L(g1) | |
| 56 | lwzu rWORD, 4(rSRC) | |
| 57 | stwu rALT, 4(rDEST) | |
| 58 | L(g2): add rTMP, rFEFE, rWORD | |
| 59 | nor rNEG, r7F7F, rWORD | |
| 60 | and. rTMP, rTMP, rNEG | |
| 61 | beq+ L(g0) | |
| 62 | ||
| 63 | mr rALT, rWORD | |
| 650425ce | 64 | /* We've hit the end of the string. Do the rest byte-by-byte. */ |
| 1d280d9f GM |
65 | L(g1): rlwinm. rTMP, rALT, 8, 24, 31 |
| 66 | stb rTMP, 4(rDEST) | |
| 650425ce | 67 | beqlr- |
| 1d280d9f GM |
68 | rlwinm. rTMP, rALT, 16, 24, 31 |
| 69 | stb rTMP, 5(rDEST) | |
| 650425ce | 70 | beqlr- |
| 1d280d9f GM |
71 | rlwinm. rTMP, rALT, 24, 24, 31 |
| 72 | stb rTMP, 6(rDEST) | |
| 650425ce | 73 | beqlr- |
| 1d280d9f | 74 | stb rALT, 7(rDEST) |
| 650425ce UD |
75 | blr |
| 76 | ||
| 77 | /* Oh well. In this case, we just do a byte-by-byte copy. */ | |
| 78 | .align 4 | |
| 79 | nop | |
| 80 | L(unaligned): | |
| 1d280d9f GM |
81 | lbz rWORD, 0(rSRC) |
| 82 | addi rDEST, rRTN, -1 | |
| 83 | cmpwi rWORD, 0 | |
| 84 | beq- L(u2) | |
| 650425ce | 85 | |
| 1d280d9f GM |
86 | L(u0): lbzu rALT, 1(rSRC) |
| 87 | stbu rWORD, 1(rDEST) | |
| 88 | cmpwi rALT, 0 | |
| 89 | beq- L(u1) | |
| 650425ce | 90 | nop /* Let 601 load start of loop. */ |
| 1d280d9f GM |
91 | lbzu rWORD, 1(rSRC) |
| 92 | stbu rALT, 1(rDEST) | |
| 93 | cmpwi rWORD, 0 | |
| 94 | bne+ L(u0) | |
| 95 | L(u2): stb rWORD, 1(rDEST) | |
| 650425ce | 96 | blr |
| 1d280d9f | 97 | L(u1): stb rALT, 1(rDEST) |
| 650425ce UD |
98 | blr |
| 99 | ||
| 100 | END(strcpy) |