| /* Copy memory to memory until the specified number of bytes |
| has been copied. Overlap is handled correctly. |
| For SPARC V9. |
| Copyright (C) 2017-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <sysdep.h> |
| |
| #ifndef XCC |
| # define XCC xcc |
| .register %g2, #scratch |
| #endif |
| |
| ENTRY(memmove) |
| mov %o0, %g2 /* Save pointer to destination */ |
| cmp %o1, %o0 /* if from address is >= to use forward copy */ |
| bgeu,a %XCC, 2f /* else use backward if ... */ |
| cmp %o2, 17 /* delay slot, for small counts copy bytes */ |
| |
| sub %o0, %o1, %o4 /* get difference of two addresses */ |
| cmp %o2, %o4 /* compare size and difference of addresses */ |
| bgu %XCC, .Lovbc /* if size is bigger, have to do overlapped copy */ |
| cmp %o2, 17 /* delay slot, for small counts copy bytes */ |
| /* |
| * normal, copy forwards |
| */ |
| 2: ble %XCC, .Ldbytecp |
| andcc %o1, 3, %o5 /* is src word aligned */ |
| bz,pn %icc, .Laldst |
| cmp %o5, 2 /* is src half-word aligned */ |
| be,pn %icc, .Ls2alg |
| cmp %o5, 3 /* src is byte aligned */ |
| ldub [%o1], %o3 /* move 1 or 3 bytes to align it */ |
| inc 1, %o1 |
| stb %o3, [%o0] /* move a byte to align src */ |
| inc 1, %o0 |
| bne,pn %icc, .Ls2alg |
| dec %o2 |
| b .Lald /* now go align dest */ |
| andcc %o0, 3, %o5 |
| |
| .Ls2alg: |
| lduh [%o1], %o3 /* know src is 2 byte aligned */ |
| inc 2, %o1 |
| srl %o3, 8, %o4 |
| stb %o4, [%o0] /* have to do bytes, */ |
| stb %o3, [%o0 + 1] /* don't know dst alingment */ |
| inc 2, %o0 |
| dec 2, %o2 |
| |
| .Laldst: |
| andcc %o0, 3, %o5 /* align the destination address */ |
| .Lald: bz,pn %icc, .Lw4cp |
| cmp %o5, 2 |
| bz,pn %icc, .Lw2cp |
| cmp %o5, 3 |
| .Lw3cp: |
| lduw [%o1], %o4 |
| inc 4, %o1 |
| srl %o4, 24, %o5 |
| stb %o5, [%o0] |
| bne,pt %icc, .Lw1cp |
| inc %o0 |
| dec 1, %o2 |
| andn %o2, 3, %o3 /* i3 is aligned word count */ |
| dec 4, %o3 /* avoid reading beyond tail of src */ |
| sub %o1, %o0, %o1 /* i1 gets the difference */ |
| |
| 1: sll %o4, 8, %g1 /* save residual bytes */ |
| lduw [%o1+%o0], %o4 |
| deccc 4, %o3 |
| srl %o4, 24, %o5 /* merge with residual */ |
| or %o5, %g1, %g1 |
| st %g1, [%o0] |
| bnz,pt %XCC, 1b |
| inc 4, %o0 |
| sub %o1, 3, %o1 /* used one byte of last word read */ |
| and %o2, 3, %o2 |
| b 7f |
| inc 4, %o2 |
| |
| .Lw1cp: |
| srl %o4, 8, %o5 |
| sth %o5, [%o0] |
| inc 2, %o0 |
| dec 3, %o2 |
| andn %o2, 3, %o3 |
| dec 4, %o3 /* avoid reading beyond tail of src */ |
| sub %o1, %o0, %o1 /* i1 gets the difference */ |
| |
| 2: sll %o4, 24, %g1 /* save residual bytes */ |
| lduw [%o1+%o0], %o4 |
| deccc 4, %o3 |
| srl %o4, 8, %o5 /* merge with residual */ |
| or %o5, %g1, %g1 |
| st %g1, [%o0] |
| bnz,pt %XCC, 2b |
| inc 4, %o0 |
| sub %o1, 1, %o1 /* used three bytes of last word read */ |
| and %o2, 3, %o2 |
| b 7f |
| inc 4, %o2 |
| |
| .Lw2cp: |
| lduw [%o1], %o4 |
| inc 4, %o1 |
| srl %o4, 16, %o5 |
| sth %o5, [%o0] |
| inc 2, %o0 |
| dec 2, %o2 |
| andn %o2, 3, %o3 /* i3 is aligned word count */ |
| dec 4, %o3 /* avoid reading beyond tail of src */ |
| sub %o1, %o0, %o1 /* i1 gets the difference */ |
| |
| 3: sll %o4, 16, %g1 /* save residual bytes */ |
| lduw [%o1+%o0], %o4 |
| deccc 4, %o3 |
| srl %o4, 16, %o5 /* merge with residual */ |
| or %o5, %g1, %g1 |
| st %g1, [%o0] |
| bnz,pt %XCC, 3b |
| inc 4, %o0 |
| sub %o1, 2, %o1 /* used two bytes of last word read */ |
| and %o2, 3, %o2 |
| b 7f |
| inc 4, %o2 |
| |
| .Lw4cp: |
| andn %o2, 3, %o3 /* i3 is aligned word count */ |
| sub %o1, %o0, %o1 /* i1 gets the difference */ |
| |
| 1: lduw [%o1+%o0], %o4 /* read from address */ |
| deccc 4, %o3 /* decrement count */ |
| st %o4, [%o0] /* write at destination address */ |
| bg,pt %XCC, 1b |
| inc 4, %o0 /* increment to address */ |
| b 7f |
| and %o2, 3, %o2 /* number of leftover bytes, if any */ |
| |
| /* |
| * differenced byte copy, works with any alignment |
| */ |
| .Ldbytecp: |
| b 7f |
| sub %o1, %o0, %o1 /* i1 gets the difference */ |
| |
| 4: stb %o4, [%o0] /* write to address */ |
| inc %o0 /* inc to address */ |
| 7: deccc %o2 /* decrement count */ |
| bge,a %XCC, 4b /* loop till done */ |
| ldub [%o1+%o0], %o4 /* read from address */ |
| retl |
| mov %g2, %o0 /* return pointer to destination */ |
| |
| /* |
| * an overlapped copy that must be done "backwards" |
| */ |
| .Lovbc: |
| add %o1, %o2, %o1 /* get to end of source space */ |
| add %o0, %o2, %o0 /* get to end of destination space */ |
| sub %o1, %o0, %o1 /* i1 gets the difference */ |
| |
| 5: dec %o0 /* decrement to address */ |
| ldub [%o1+%o0], %o3 /* read a byte */ |
| deccc %o2 /* decrement count */ |
| bg,pt %XCC, 5b /* loop until done */ |
| stb %o3, [%o0] /* write byte */ |
| retl |
| mov %g2, %o0 /* return pointer to destination */ |
| END(memmove) |
| |
| libc_hidden_builtin_def (memmove) |
