Add RISC-V port for newlib

  Contributor list:
    - Andrew Waterman  <andrew@sifive.com>
    - Palmer Dabbelt  <palmer@dabbelt.com>
    - Kito Cheng  <kito.cheng@gmail.com>
    - Scott Beamer  <sbeamer@eecs.berkeley.edu>

1 files changed, 64 insertions, 0 deletions

diff --git a/newlib/libc/machine/riscv/strcpy.c b/newlib/libc/machine/riscv/strcpy.c
new file mode 100644
index 000000000..905a9b8df
--- /dev/null
+++ b/newlib/libc/machine/riscv/strcpy.c
@@ -0,0 +1,64 @@
+/* Copyright (c) 2017  SiFive Inc. All rights reserved.
+
+   This copyrighted material is made available to anyone wishing to use,
+   modify, copy, or redistribute it subject to the terms and conditions
+   of the BSD License.   This program is distributed in the hope that
+   it will be useful, but WITHOUT ANY WARRANTY expressed or implied,
+   including the implied warranties of MERCHANTABILITY or FITNESS FOR
+   A PARTICULAR PURPOSE.  A copy of this license is available at
+   http://www.opensource.org/licenses.
+*/
+
+#include <string.h>
+#include <stdint.h>
+
+char *strcpy(char *dst, const char *src)
+{
+  char *dst0 = dst;
+
+#if !defined(PREFER_SIZE_OVER_SPEED) && !defined(__OPTIMIZE_SIZE__)
+  int misaligned = ((uintptr_t)dst | (uintptr_t)src) & (sizeof (long) - 1);
+  if (__builtin_expect(!misaligned, 1))
+    {
+      long *ldst = (long *)dst;
+      const long *lsrc = (const long *)src;
+
+      while (!__libc_detect_null(*lsrc))
+	*ldst++ = *lsrc++;
+
+      dst = (char *)ldst;
+      src = (const char *)lsrc;
+
+      char c0 = src[0];
+      char c1 = src[1];
+      char c2 = src[2];
+      if (!(*dst++ = c0)) return dst0;
+      if (!(*dst++ = c1)) return dst0;
+      char c3 = src[3];
+      if (!(*dst++ = c2)) return dst0;
+      if (sizeof (long) == 4) goto out;
+      char c4 = src[4];
+      if (!(*dst++ = c3)) return dst0;
+      char c5 = src[5];
+      if (!(*dst++ = c4)) return dst0;
+      char c6 = src[6];
+      if (!(*dst++ = c5)) return dst0;
+      if (!(*dst++ = c6)) return dst0;
+
+out:
+      *dst++ = 0;
+      return dst0;
+    }
+#endif /* not PREFER_SIZE_OVER_SPEED */
+
+  char ch;
+  do
+    {
+      ch = *src;
+      src++;
+      dst++;
+      *(dst - 1) = ch;
+    } while (ch);
+
+  return dst0;
+}