Add MIPS specific string/memory functions

1 files changed, 164 insertions, 0 deletions

diff --git a/newlib/libc/machine/mips/memcpy.c b/newlib/libc/machine/mips/memcpy.c
new file mode 100644
index 000000000..761f7e9ab
--- /dev/null
+++ b/newlib/libc/machine/mips/memcpy.c
@@ -0,0 +1,164 @@
+/*
+FUNCTION
+        <<memcpy>>---copy memory regions, optimized for the mips processors
+
+ANSI_SYNOPSIS
+        #include <string.h>
+        void* memcpy(void *<[out]>, const void *<[in]>, size_t <[n]>);
+
+TRAD_SYNOPSIS
+        void *memcpy(<[out]>, <[in]>, <[n]>
+        void *<[out]>;
+        void *<[in]>;
+        size_t <[n]>;
+
+DESCRIPTION
+        This function copies <[n]> bytes from the memory region
+        pointed to by <[in]> to the memory region pointed to by
+        <[out]>.
+
+        If the regions overlap, the behavior is undefined.
+
+RETURNS
+        <<memcpy>> returns a pointer to the first byte of the <[out]>
+        region.
+
+PORTABILITY
+<<memcpy>> is ANSI C.
+
+<<memcpy>> requires no supporting OS subroutines.
+
+QUICKREF
+        memcpy ansi pure
+	*/
+
+#include <_ansi.h>
+#include <stddef.h>
+#include <limits.h>
+
+#ifdef __mips64
+#define wordtype long long
+#else
+#define wordtype long
+#endif
+
+/* Nonzero if either X or Y is not aligned on a "long" boundary.  */
+#define UNALIGNED(X, Y) \
+  (((long)X & (sizeof (wordtype) - 1)) | ((long)Y & (sizeof (wordtype) - 1)))
+
+/* How many bytes are copied each iteration of the 4X unrolled loop.  */
+#define BIGBLOCKSIZE    (sizeof (wordtype) << 2)
+
+/* How many bytes are copied each iteration of the word copy loop.  */
+#define LITTLEBLOCKSIZE (sizeof (wordtype))
+
+/* Threshhold for punting to the byte copier.  */
+#define TOO_SMALL(LEN)  ((LEN) < BIGBLOCKSIZE)
+
+_PTR
+_DEFUN (memcpy, (dst0, src0, len0),
+	_PTR dst0 _AND
+	_CONST _PTR src0 _AND
+	size_t len0)
+{
+#if defined(PREFER_SIZE_OVER_SPEED) || defined(__OPTIMIZE_SIZE__) || defined(__mips16)
+  char *dst = (char *) dst0;
+  char *src = (char *) src0;
+
+  _PTR save = dst0;
+
+  while (len0--)
+    {
+      *dst++ = *src++;
+    }
+
+  return save;
+#else
+  char *dst = dst0;
+  _CONST char *src = src0;
+  wordtype *aligned_dst;
+  _CONST wordtype *aligned_src;
+  int   len =  len0;
+  size_t iter;
+
+  /* Handle aligned moves here.  */
+  if (!UNALIGNED (src, dst))
+    {
+      iter = len / BIGBLOCKSIZE;
+      len = len % BIGBLOCKSIZE;
+      aligned_dst = (wordtype *)dst;
+      aligned_src = (wordtype *)src;
+
+	  /* Copy 4X long or long long words at a time if possible.  */
+      while (iter > 0)
+	{
+	  wordtype tmp0 = aligned_src[0];
+	  wordtype tmp1 = aligned_src[1];
+	  wordtype tmp2 = aligned_src[2];
+	  wordtype tmp3 = aligned_src[3];
+
+	  aligned_dst[0] = tmp0;
+	  aligned_dst[1] = tmp1;
+	  aligned_dst[2] = tmp2;
+	  aligned_dst[3] = tmp3;
+	  aligned_src += 4;
+	  aligned_dst += 4;
+	  iter--;
+	}
+
+      /* Copy one long or long long word at a time if possible.  */
+      iter = len / LITTLEBLOCKSIZE;
+      len = len % LITTLEBLOCKSIZE;
+
+      while (iter > 0)
+	{
+	  *aligned_dst++ = *aligned_src++;
+	  iter--;
+	}
+
+      /* Pick up any residual with a byte copier.  */
+      dst = (char*)aligned_dst;
+      src = (char*)aligned_src;
+
+      while (len > 0)
+	{
+	  *dst++ = *src++;
+	  len--;
+	}
+
+      return dst0;
+    }
+
+  /* Handle unaligned moves here, using lwr/lwl and swr/swl where possible */
+  else
+    {
+#ifndef NO_UNALIGNED_LOADSTORE
+      int tmp;
+      int *int_src = (int *)src;
+      int *int_dst = (int *)dst;
+      iter = len / 4;
+      len = len % 4;
+      while (iter > 0)
+	{
+	  __asm__ ("ulw %0,%1" : "=r" (tmp) : "m" (*int_src));
+	  iter--;
+	  int_src++;
+	  __asm__ ("usw %1,%0" : "=m" (*int_dst) : "r" (tmp));
+	  int_dst++;
+	}
+
+      /* Pick up any residual with a byte copier.  */
+      dst = (char*)int_dst;
+      src = (char*)int_src;
+#endif
+
+      while (len > 0)
+	{
+	  *dst++ = *src++;
+	  len--;
+	}
+
+      return dst0;
+    }
+#endif /* not PREFER_SIZE_OVER_SPEED */
+}