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authorWill Schmidt <will_schmidt@vnet.ibm.com>2012-04-18 16:44:27 -0500
committerRyan S. Arnold <rsa@linux.vnet.ibm.com>2012-04-18 16:44:27 -0500
commit8ff41c4601f8b8d7dfa6682f596dc4071823424d (patch)
treed28fec98f6e2e4a65f85d594ff7d38989bcfa1de /sysdeps
parent6b652f46c3935088082bb5870b6fd9edbaa92125 (diff)
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Have memmove call __builtin_memcopy on PowerPC if src and dest don't overlap.
Diffstat (limited to 'sysdeps')
-rw-r--r--sysdeps/powerpc/memmove.c119
1 files changed, 119 insertions, 0 deletions
diff --git a/sysdeps/powerpc/memmove.c b/sysdeps/powerpc/memmove.c
new file mode 100644
index 0000000000..4887ae356f
--- /dev/null
+++ b/sysdeps/powerpc/memmove.c
@@ -0,0 +1,119 @@
+/* Copy memory to memory until the specified number of bytes
+ has been copied. Overlap is handled correctly.
+ Copyright (C) 1991-2012 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Torbjorn Granlund (tege@sics.se).
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <string.h>
+#include <memcopy.h>
+#include <pagecopy.h>
+
+/* All this is so that bcopy.c can #include
+ this file after defining some things. */
+#ifndef a1
+#define a1 dest /* First arg is DEST. */
+#define a1const
+#define a2 src /* Second arg is SRC. */
+#define a2const const
+#undef memmove
+#endif
+#if !defined(RETURN) || !defined(rettype)
+#define RETURN(s) return (s) /* Return DEST. */
+#define rettype void *
+#endif
+
+#ifndef MEMMOVE
+#define MEMMOVE memmove
+#endif
+
+rettype
+MEMMOVE (a1, a2, len)
+ a1const void *a1;
+ a2const void *a2;
+ size_t len;
+{
+ unsigned long int dstp = (long int) dest;
+ unsigned long int srcp = (long int) src;
+
+ /* If there is no overlap between ranges, call the builtin memcpy. */
+ if ( (dstp >= (srcp + len)) || (srcp > (dstp + len)) )
+ return __builtin_memcpy (dest, src, len);
+
+ /* This test makes the forward copying code be used whenever possible.
+ Reduces the working set. */
+ if (dstp - srcp >= len) /* *Unsigned* compare! */
+ {
+ /* Copy from the beginning to the end. */
+
+ /* If there not too few bytes to copy, use word copy. */
+ if (len >= OP_T_THRES)
+ {
+ /* Copy just a few bytes to make DSTP aligned. */
+ len -= (-dstp) % OPSIZ;
+ BYTE_COPY_FWD (dstp, srcp, (-dstp) % OPSIZ);
+
+ /* Copy whole pages from SRCP to DSTP by virtual address
+ manipulation, as much as possible. */
+
+ PAGE_COPY_FWD_MAYBE (dstp, srcp, len, len);
+
+ /* Copy from SRCP to DSTP taking advantage of the known
+ alignment of DSTP. Number of bytes remaining is put
+ in the third argument, i.e. in LEN. This number may
+ vary from machine to machine. */
+
+ WORD_COPY_FWD (dstp, srcp, len, len);
+
+ /* Fall out and copy the tail. */
+ }
+
+ /* There are just a few bytes to copy. Use byte memory operations. */
+ BYTE_COPY_FWD (dstp, srcp, len);
+ }
+ else
+ {
+ /* Copy from the end to the beginning. */
+ srcp += len;
+ dstp += len;
+
+ /* If there not too few bytes to copy, use word copy. */
+ if (len >= OP_T_THRES)
+ {
+ /* Copy just a few bytes to make DSTP aligned. */
+ len -= dstp % OPSIZ;
+ BYTE_COPY_BWD (dstp, srcp, dstp % OPSIZ);
+
+ /* Copy from SRCP to DSTP taking advantage of the known
+ alignment of DSTP. Number of bytes remaining is put
+ in the third argument, i.e. in LEN. This number may
+ vary from machine to machine. */
+
+ WORD_COPY_BWD (dstp, srcp, len, len);
+
+ /* Fall out and copy the tail. */
+ }
+
+ /* There are just a few bytes to copy. Use byte memory operations. */
+ BYTE_COPY_BWD (dstp, srcp, len);
+ }
+
+ RETURN (dest);
+}
+#ifndef memmove
+libc_hidden_builtin_def (memmove)
+#endif