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Diffstat (limited to 'sysdeps/mips/memset.S')
| -rw-r--r-- | sysdeps/mips/memset.S | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/sysdeps/mips/memset.S b/sysdeps/mips/memset.S new file mode 100644 index 0000000000..694ee8f1dc --- /dev/null +++ b/sysdeps/mips/memset.S @@ -0,0 +1,86 @@ +/* Copyright (C) 2002, 2003 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Hartvig Ekner <hartvige@mips.com>, 2002. + + 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <sysdep.h> +#include <endian.h> + + +/* void *memset(void *s, int c, size_t n). */ + +#if __BYTE_ORDER == __BIG_ENDIAN +# define SWHI swl /* high part is left in big-endian */ +#else +# define SWHI swr /* high part is right in little-endian */ +#endif + +ENTRY (memset) + .set noreorder + + slti t1, a2, 8 # Less than 8? + bne t1, zero, L(last8) + move v0, a0 # Setup exit value before too late + + beq a1, zero, L(ueven) # If zero pattern, no need to extend + andi a1, 0xff # Avoid problems with bogus arguments + sll t0, a1, 8 + or a1, t0 + sll t0, a1, 16 + or a1, t0 # a1 is now pattern in full word + +L(ueven): + subu t0, zero, a0 # Unaligned address? + andi t0, 0x3 + beq t0, zero, L(chkw) + subu a2, t0 + SWHI a1, 0(a0) # Yes, handle first unaligned part + addu a0, t0 # Now both a0 and a2 are updated + +L(chkw): + andi t0, a2, 0x7 # Enough left for one loop iteration? + beq t0, a2, L(chkl) + subu a3, a2, t0 + addu a3, a0 # a3 is last loop address +1 + move a2, t0 # a2 is now # of bytes left after loop +L(loopw): + addiu a0, 8 # Handle 2 words pr. iteration + sw a1, -8(a0) + bne a0, a3, L(loopw) + sw a1, -4(a0) + +L(chkl): + andi t0, a2, 0x4 # Check if there is at least a full + beq t0, zero, L(last8) # word remaining after the loop + subu a2, t0 + sw a1, 0(a0) # Yes... + addiu a0, 4 + +L(last8): + blez a2, L(exit) # Handle last 8 bytes (if cnt>0) + addu a3, a2, a0 # a3 is last address +1 +L(lst8l): + addiu a0, 1 + bne a0, a3, L(lst8l) + sb a1, -1(a0) +L(exit): + j ra # Bye, bye + nop + + .set reorder +END (memset) +libc_hidden_builtin_def (memset) |