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Diffstat (limited to 'sysdeps/mips/mips64/memset.S')
-rw-r--r-- | sysdeps/mips/mips64/memset.S | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/sysdeps/mips/mips64/memset.S b/sysdeps/mips/mips64/memset.S new file mode 100644 index 0000000000..b50aaba816 --- /dev/null +++ b/sysdeps/mips/mips64/memset.S @@ -0,0 +1,92 @@ +/* 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. + Ported to mips3 n32/n64 by Alexandre Oliva <aoliva@redhat.com> + + 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> +#include <sys/asm.h> + + +/* void *memset(void *s, int c, size_t n); + + This could probably be optimized further. */ + +#if __BYTE_ORDER == __BIG_ENDIAN +# define SDHI sdl /* high part is left in big-endian */ +#else +# define SDHI sdr /* high part is right in little-endian */ +#endif + +ENTRY (memset) + .set noreorder + + slti ta1, a2, 16 # Less than 16? + bne ta1, zero, L(last16) + 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 + dsll ta0, a1, 8 + or a1, ta0 + dsll ta0, a1, 16 + or a1, ta0 # a1 is now pattern in full word + dsll ta0, a1, 32 + or a1, ta0 # a1 is now pattern in double word + +L(ueven): + PTR_SUBU ta0, zero, a0 # Unaligned address? + andi ta0, 0x7 + beq ta0, zero, L(chkw) + PTR_SUBU a2, ta0 + SDHI a1, 0(a0) # Yes, handle first unaligned part + PTR_ADDU a0, ta0 # Now both a0 and a2 are updated + +L(chkw): + andi ta0, a2, 0xf # Enough left for one loop iteration? + beq ta0, a2, L(chkl) + PTR_SUBU a3, a2, ta0 + PTR_ADDU a3, a0 # a3 is last loop address +1 + move a2, ta0 # a2 is now # of bytes left after loop +L(loopw): + PTR_ADDIU a0, 16 # Handle 2 dwords pr. iteration + sd a1, -16(a0) + bne a0, a3, L(loopw) + sd a1, -8(a0) + +L(chkl): + andi ta0, a2, 0x8 # Check if there is at least a double + beq ta0, zero, L(last16) # word remaining after the loop + PTR_SUBU a2, ta0 + sd a1, 0(a0) # Yes... + PTR_ADDIU a0, 8 + +L(last16): + blez a2, L(exit) # Handle last 16 bytes (if cnt>0) + PTR_ADDU a3, a2, a0 # a3 is last address +1 +L(lst16l): + PTR_ADDIU a0, 1 + bne a0, a3, L(lst16l) + sb a1, -1(a0) +L(exit): + j ra # Bye, bye + nop + + .set reorder +END (memset) +libc_hidden_builtin_def (memset) |