diff options
Diffstat (limited to 'lib/libc/ia64/string/bcopy.S')
-rw-r--r-- | lib/libc/ia64/string/bcopy.S | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/lib/libc/ia64/string/bcopy.S b/lib/libc/ia64/string/bcopy.S new file mode 100644 index 0000000..5a2f9fd --- /dev/null +++ b/lib/libc/ia64/string/bcopy.S @@ -0,0 +1,96 @@ +/*- + * Copyright (c) 2000 Doug Rabson + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#include <machine/asm.h> + +/* + * Not the fastest bcopy in the world. + */ +ENTRY(bcopy, 3) + + cmp.le p6,p0=in2,r0 // bail if len <= 0 +(p6) br.ret.spnt.few rp + + sub r14=in1,in0 ;; // check for overlap + cmp.ltu p6,p0=r14,in2 // dst-src < len +(p6) br.cond.spnt.few 5f + + extr.u r14=in0,0,3 // src & 7 + extr.u r15=in1,0,3 ;; // dst & 7 + cmp.eq p6,p0=r14,r15 // different alignment? +(p6) br.cond.spnt.few 2f // branch if same alignment + +1: ld1 r14=[in0],1 ;; // copy bytewise + st1 [in1]=r14,1 + add in2=-1,in2 ;; // len-- + cmp.ne p6,p0=r0,in2 +(p6) br.cond.dptk.few 1b // loop + br.ret.sptk.few rp // done + +2: cmp.eq p6,p0=r14,r0 // aligned? +(p6) br.cond.sptk.few 4f + +3: ld1 r14=[in0],1 ;; // copy bytewise + st1 [in1]=r14,1 + extr.u r15=in0,0,3 // src & 7 + add in2=-1,in2 ;; // len-- + cmp.eq p6,p0=r0,in2 // done? + cmp.eq p7,p0=r0,r15 ;; // aligned now? +(p6) br.ret.spnt.few rp // return if done +(p7) br.cond.spnt.few 4f // go to main copy + br.cond.sptk.few 3b // more bytes to copy + + // At this point, in2 is non-zero + +4: mov r14=8 ;; + cmp.ltu p6,p0=in2,r14 ;; // len < 8? +(p6) br.cond.spnt.few 1b // byte copy the end + ld8 r15=[in0],8 ;; // copy word + st8 [in1]=r15,8 + add in2=-8,in2 ;; // len -= 8 + cmp.ne p6,p0=r0,in2 // done? +(p6) br.cond.spnt.few 4b // again + + br.ret.sptk.few rp // return + + // Don't bother optimising overlap case + +5: add in0=in0,in2 + add in1=in1,in2 ;; + add in0=-1,in0 + add in1=-1,in1 ;; + +6: ld1 r14=[in0],-1 ;; + st1 [in1]=r14,-1 + add in2=-1,in2 ;; + cmp.ne p6,p0=r0,in2 +(p6) br.cond.spnt.few 6b + + br.ret.sptk.few rp + +END(bcopy) |