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Diffstat (limited to 'newlib/libc/machine/mips/memcpy.c')
-rw-r--r--newlib/libc/machine/mips/memcpy.c164
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 */
+}