patch-2.1.101 linux/arch/mips/lib/memset.S

• Lines: 142
• Date: Fri May 8 00:13:24 1998
• Orig file: v2.1.100/linux/arch/mips/lib/memset.S
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.100/linux/arch/mips/lib/memset.S linux/arch/mips/lib/memset.S
@@ -0,0 +1,141 @@
+/*
+ * include/asm-mips/types.h
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1998 by Ralf Baechle
+ *
+ * $Id: memset.S,v 1.1 1998/05/04 09:18:18 ralf Exp $
+ */
+#include <asm/asm.h>
+#include <asm/offset.h>
+#include <asm/regdef.h>
+
+#define EX(insn,reg,addr,handler)			\
+9:	insn	reg, addr;				\
+	.section __ex_table,"a"; 			\
+	PTR	9b, handler; 				\
+	.previous
+
+#define F_FILL64(dst, offset, val, fixup)		\
+	EX(sw, val, (offset + 0x00)(dst), fixup);	\
+	EX(sw, val, (offset + 0x04)(dst), fixup);	\
+	EX(sw, val, (offset + 0x08)(dst), fixup);	\
+	EX(sw, val, (offset + 0x0c)(dst), fixup);	\
+	EX(sw, val, (offset + 0x10)(dst), fixup);	\
+	EX(sw, val, (offset + 0x14)(dst), fixup);	\
+	EX(sw, val, (offset + 0x18)(dst), fixup);	\
+	EX(sw, val, (offset + 0x1c)(dst), fixup);	\
+	EX(sw, val, (offset + 0x20)(dst), fixup);	\
+	EX(sw, val, (offset + 0x24)(dst), fixup);	\
+	EX(sw, val, (offset + 0x28)(dst), fixup);	\
+	EX(sw, val, (offset + 0x2c)(dst), fixup);	\
+	EX(sw, val, (offset + 0x30)(dst), fixup);	\
+	EX(sw, val, (offset + 0x34)(dst), fixup);	\
+	EX(sw, val, (offset + 0x38)(dst), fixup);	\
+	EX(sw, val, (offset + 0x3c)(dst), fixup)
+
+/*
+ * memset(void *s, int c, size_t n)
+ *
+ * a0: start of area to clear
+ * a1: char to fill with
+ * a2: size of area to clear
+ */
+	.set	noreorder
+	.align	5
+LEAF(memset)
+	beqz	a1, 1f
+	 move	v0, a0				/* result */
+
+	andi	a1, 0xff			/* spread fillword */
+	sll	t1, a1, 8
+	or	a1, t1
+	sll	t1, a1, 16
+	or	a1, t1
+1:
+
+EXPORT(__bzero)
+	sltiu	t0, a2, 4			/* very small region? */
+	bnez	t0, small_memset
+	 andi	t0, a0, 3			/* aligned? */
+
+	beqz	t0, 1f
+	 subu	t0, 4				/* alignment in bytes */
+
+#ifdef __MIPSEB__
+	EX(swl, a1, (a0), first_fixup)		/* make word aligned */
+#endif
+#ifdef __MIPSEL__
+	EX(swr, a1, (a0), first_fixup)		/* make word aligned */
+#endif
+	subu	a0, t0				/* word align ptr */
+	addu	a2, t0				/* correct size */
+
+1:	ori	t1, a2, 0x3f			/* # of full blocks */
+	xori	t1, 0x3f
+	beqz	t1, memset_partial		/* no block to fill */
+	 andi	t0, a2, 0x3c
+
+	addu	t1, a0				/* end address */
+	.set	reorder
+1:	addiu	a0, 64
+	F_FILL64(a0, -64, a1, fwd_fixup)
+	bne	t1, a0, 1b
+	.set	noreorder
+
+memset_partial:
+	la	t1, 2f				/* where to start */
+	subu	t1, t0
+	jr	t1
+	 addu	a0, t0				/* dest ptr */
+
+	F_FILL64(a0, -64, a1, partial_fixup)	/* ... but first do wrds ... */
+2:	andi	a2, 3				/* 0 <= n <= 3 to go */
+
+	beqz	a2, 1f
+	 addu	a0, a2				/* What's left */
+#ifdef __MIPSEB__
+	EX(swr, a1, -1(a0), last_fixup)
+#endif
+#ifdef __MIPSEL__
+	EX(swl, a1, -1(a0), last_fixup)
+#endif
+1:	jr	ra
+	 move	a2, zero
+
+small_memset:
+	beqz	a2, 2f
+	 addu	t1, a0, a2
+
+1:	addiu	a0, 1				/* fill bytewise */
+	bne	t1, a0, 1b
+	 sb	a1, -1(a0)
+
+2:	jr	ra				/* done */
+	 move	a2, zero
+	END(memset)
+
+first_fixup:
+	jr	ra
+	 nop
+
+fwd_fixup:
+	lw	t0, THREAD_BUADDR($28)
+	andi	a2, 0x3f
+	addu	a2, t1
+	jr	ra
+	 subu	a2, t0
+
+partial_fixup:
+	lw	t0, THREAD_BUADDR($28)
+	andi	a2, 3
+	addu	a2, t1
+	jr	ra
+	 subu	a2, t0
+
+last_fixup:
+	jr	ra
+	 andi	v1, a2, 3