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Diffstat (limited to 'sysdeps/sparc/sparc64/memmove.S')
| -rw-r--r-- | sysdeps/sparc/sparc64/memmove.S | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/sysdeps/sparc/sparc64/memmove.S b/sysdeps/sparc/sparc64/memmove.S new file mode 100644 index 0000000000..117786bc1c --- /dev/null +++ b/sysdeps/sparc/sparc64/memmove.S @@ -0,0 +1,186 @@ +/* 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) |