projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| cf182b58 UD |
1 | /* Copyright (C) 1996 Free Software Foundation, Inc. |
| 2 | Contributed by Richard Henderson (rth@tamu.edu) | |
| 3 | ||
| 4 | This file is part of the GNU C Library. | |
| 5 | ||
| 6 | The GNU C Library is free software; you can redistribute it and/or | |
| 7 | modify it under the terms of the GNU Library General Public License as | |
| 8 | published by the Free Software Foundation; either version 2 of the | |
| 9 | License, or (at your option) any later version. | |
| 10 | ||
| 11 | The GNU C Library is distributed in the hope that it will be useful, | |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 14 | Library General Public License for more details. | |
| 15 | ||
| 16 | You should have received a copy of the GNU Library General Public | |
| 17 | License along with the GNU C Library; see the file COPYING.LIB. If | |
| 18 | not, write to the Free Software Foundation, Inc., 675 Mass Ave, | |
| 19 | Cambridge, MA 02139, USA. */ | |
| 20 | ||
| 21 | /* Append a null-terminated string from SRC to DST. */ | |
| 22 | ||
| 23 | #include <sysdep.h> | |
| 24 | ||
| 25 | .text | |
| 26 | ||
| 27 | ENTRY(strcat) | |
| 28 | ldgp gp, 0(pv) | |
| 29 | .prologue 1 | |
| 30 | ||
| 31 | mov a0, v0 # set up return value | |
| 32 | ||
| 33 | /* Find the end of the string. */ | |
| 34 | ||
| 35 | ldq_u t0, 0(a0) # load first quadword (a0 may be misaligned) | |
| 36 | lda t1, -1(zero) | |
| 37 | insqh t1, a0, t1 | |
| 38 | andnot a0, 7, a0 | |
| 39 | or t1, t0, t0 | |
| 40 | cmpbge zero, t0, t1 # t1 <- bitmask: bit i == 1 <==> i-th byte == 0 | |
| 41 | bne t1, $found | |
| 42 | ||
| 43 | $loop: ldq t0, 8(a0) | |
| 44 | addq a0, 8, a0 # addr += 8 | |
| 45 | cmpbge zero, t0, t1 | |
| 46 | beq t1, $loop | |
| 47 | ||
| 48 | $found: negq t1, t2 # clear all but least set bit | |
| 49 | and t1, t2, t1 | |
| 50 | ||
| 51 | and t1, 0xf0, t2 # binary search for that set bit | |
| 52 | and t1, 0xcc, t3 | |
| 53 | and t1, 0xaa, t4 | |
| 54 | cmovne t2, 4, t2 | |
| 55 | cmovne t3, 2, t3 | |
| 56 | cmovne t4, 1, t4 | |
| 57 | addq t2, t3, t2 | |
| 58 | addq a0, t4, a0 | |
| 59 | addq a0, t2, a0 | |
| 60 | ||
| 61 | /* Now do the append. */ | |
| 62 | ||
| 63 | jsr t9, __stxcpy | |
| 64 | ret | |
| 65 | ||
| 66 | END(strcat) |