summary refs log tree commit diff
path: root/ports/sysdeps/mips/mips64/memset.S
diff options
context:
space:
mode:
Diffstat (limited to 'ports/sysdeps/mips/mips64/memset.S')
-rw-r--r--ports/sysdeps/mips/mips64/memset.S90
1 files changed, 90 insertions, 0 deletions
diff --git a/ports/sysdeps/mips/mips64/memset.S b/ports/sysdeps/mips/mips64/memset.S
new file mode 100644
index 0000000000..a2f9120e86
--- /dev/null
+++ b/ports/sysdeps/mips/mips64/memset.S
@@ -0,0 +1,90 @@
+/* Copyright (C) 2002-2012 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+#include <sys/asm.h>
+
+
+/* void *memset(void *s, int c, size_t n);
+	
+   This could probably be optimized further.  */
+
+#if __MIPSEB
+# 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)