1 files changed, 67 insertions, 0 deletions
diff --git a/arch/arc/lib/strcpy-700.S b/arch/arc/lib/strcpy-700.S
new file mode 100644
index 0000000000..41bb53e501
--- /dev/null
+++ b/arch/arc/lib/strcpy-700.S
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2014 Synopsys, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+/*
+ * If dst and src are 4 byte aligned, copy 8 bytes at a time.
+ * If the src is 4, but not 8 byte aligned, we first read 4 bytes to get
+ * it 8 byte aligned.  Thus, we can do a little read-ahead, without
+ * dereferencing a cache line that we should not touch.
+ * Note that short and long instructions have been scheduled to avoid
+ * branch stalls.
+ * The beq_s to r3z could be made unaligned & long to avoid a stall
+ * there, but it is not likely to be taken often, and it would also be likely
+ * to cost an unaligned mispredict at the next call.
+ */
+
+.global strcpy
+.align 4
+strcpy:
+	or	%r2, %r0, %r1
+	bmsk_s	%r2, %r2, 1
+	brne.d	%r2, 0, charloop
+	mov_s	%r10, %r0
+	ld_s	%r3, [%r1, 0]
+	mov	%r8, 0x01010101
+	bbit0.d	%r1, 2, loop_start
+	ror	%r12, %r8
+	sub	%r2, %r3, %r8
+	bic_s	%r2, %r2, %r3
+	tst_s	%r2,%r12
+	bne	r3z
+	mov_s	%r4,%r3
+	.balign 4
+loop:
+	ld.a	%r3, [%r1, 4]
+	st.ab	%r4, [%r10, 4]
+loop_start:
+	ld.a	%r4, [%r1, 4]
+	sub	%r2, %r3, %r8
+	bic_s	%r2, %r2, %r3
+	tst_s	%r2, %r12
+	bne_s	r3z
+	st.ab	%r3, [%r10, 4]
+	sub	%r2, %r4, %r8
+	bic	%r2, %r2, %r4
+	tst	%r2, %r12
+	beq	loop
+	mov_s	%r3, %r4
+#ifdef __LITTLE_ENDIAN__
+r3z:	bmsk.f	%r1, %r3, 7
+	lsr_s	%r3, %r3, 8
+#else /* __BIG_ENDIAN__ */
+r3z:	lsr.f	%r1, %r3, 24
+	asl_s	%r3, %r3, 8
+#endif /* _ENDIAN__ */
+	bne.d	r3z
+	stb.ab	%r1, [%r10, 1]
+	j_s	[%blink]
+
+	.balign	4
+charloop:
+	ldb.ab	%r3, [%r1, 1]
+	brne.d	%r3, 0, charloop
+	stb.ab	%r3, [%r10, 1]
+	j	[%blink]