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-rw-r--r--arch/nios2/lib/memcpy.c202
1 files changed, 202 insertions, 0 deletions
diff --git a/arch/nios2/lib/memcpy.c b/arch/nios2/lib/memcpy.c
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+++ b/arch/nios2/lib/memcpy.c
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+/* Extracted from GLIBC memcpy.c and memcopy.h, which is:
+ Copyright (C) 1991, 1992, 1993, 1997, 2004 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, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <linux/types.h>
+
+/* Type to use for aligned memory operations.
+ This should normally be the biggest type supported by a single load
+ and store. */
+#define op_t unsigned long int
+#define OPSIZ (sizeof(op_t))
+
+/* Optimal type for storing bytes in registers. */
+#define reg_char char
+
+#define MERGE(w0, sh_1, w1, sh_2) (((w0) >> (sh_1)) | ((w1) << (sh_2)))
+
+/* Copy exactly NBYTES bytes from SRC_BP to DST_BP,
+ without any assumptions about alignment of the pointers. */
+#define BYTE_COPY_FWD(dst_bp, src_bp, nbytes) \
+do { \
+ size_t __nbytes = (nbytes); \
+ while (__nbytes > 0) { \
+ unsigned char __x = ((unsigned char *) src_bp)[0]; \
+ src_bp += 1; \
+ __nbytes -= 1; \
+ ((unsigned char *) dst_bp)[0] = __x; \
+ dst_bp += 1; \
+ } \
+} while (0)
+
+/* Copy *up to* NBYTES bytes from SRC_BP to DST_BP, with
+ the assumption that DST_BP is aligned on an OPSIZ multiple. If
+ not all bytes could be easily copied, store remaining number of bytes
+ in NBYTES_LEFT, otherwise store 0. */
+/* extern void _wordcopy_fwd_aligned __P ((long int, long int, size_t)); */
+/* extern void _wordcopy_fwd_dest_aligned __P ((long int, long int, size_t)); */
+#define WORD_COPY_FWD(dst_bp, src_bp, nbytes_left, nbytes) \
+do { \
+ if (src_bp % OPSIZ == 0) \
+ _wordcopy_fwd_aligned(dst_bp, src_bp, (nbytes) / OPSIZ);\
+ else \
+ _wordcopy_fwd_dest_aligned(dst_bp, src_bp, (nbytes) / OPSIZ);\
+ src_bp += (nbytes) & -OPSIZ; \
+ dst_bp += (nbytes) & -OPSIZ; \
+ (nbytes_left) = (nbytes) % OPSIZ; \
+} while (0)
+
+
+/* Threshold value for when to enter the unrolled loops. */
+#define OP_T_THRES 16
+
+/* _wordcopy_fwd_aligned -- Copy block beginning at SRCP to
+ block beginning at DSTP with LEN `op_t' words (not LEN bytes!).
+ Both SRCP and DSTP should be aligned for memory operations on `op_t's. */
+/* stream-lined (read x8 + write x8) */
+static void _wordcopy_fwd_aligned(long int dstp, long int srcp, size_t len)
+{
+ while (len > 7) {
+ register op_t a0, a1, a2, a3, a4, a5, a6, a7;
+
+ a0 = ((op_t *) srcp)[0];
+ a1 = ((op_t *) srcp)[1];
+ a2 = ((op_t *) srcp)[2];
+ a3 = ((op_t *) srcp)[3];
+ a4 = ((op_t *) srcp)[4];
+ a5 = ((op_t *) srcp)[5];
+ a6 = ((op_t *) srcp)[6];
+ a7 = ((op_t *) srcp)[7];
+ ((op_t *) dstp)[0] = a0;
+ ((op_t *) dstp)[1] = a1;
+ ((op_t *) dstp)[2] = a2;
+ ((op_t *) dstp)[3] = a3;
+ ((op_t *) dstp)[4] = a4;
+ ((op_t *) dstp)[5] = a5;
+ ((op_t *) dstp)[6] = a6;
+ ((op_t *) dstp)[7] = a7;
+
+ srcp += 8 * OPSIZ;
+ dstp += 8 * OPSIZ;
+ len -= 8;
+ }
+ while (len > 0) {
+ *(op_t *)dstp = *(op_t *)srcp;
+
+ srcp += OPSIZ;
+ dstp += OPSIZ;
+ len -= 1;
+ }
+}
+
+/* _wordcopy_fwd_dest_aligned -- Copy block beginning at SRCP to
+ block beginning at DSTP with LEN `op_t' words (not LEN bytes!).
+ DSTP should be aligned for memory operations on `op_t's, but SRCP must
+ *not* be aligned. */
+/* stream-lined (read x4 + write x4) */
+static void _wordcopy_fwd_dest_aligned(long int dstp, long int srcp,
+ size_t len)
+{
+ op_t ap;
+ int sh_1, sh_2;
+
+ /* Calculate how to shift a word read at the memory operation
+ aligned srcp to make it aligned for copy. */
+
+ sh_1 = 8 * (srcp % OPSIZ);
+ sh_2 = 8 * OPSIZ - sh_1;
+
+ /* Make SRCP aligned by rounding it down to the beginning of the `op_t'
+ it points in the middle of. */
+ srcp &= -OPSIZ;
+ ap = ((op_t *) srcp)[0];
+ srcp += OPSIZ;
+
+ while (len > 3) {
+ op_t a0, a1, a2, a3;
+
+ a0 = ((op_t *) srcp)[0];
+ a1 = ((op_t *) srcp)[1];
+ a2 = ((op_t *) srcp)[2];
+ a3 = ((op_t *) srcp)[3];
+ ((op_t *) dstp)[0] = MERGE(ap, sh_1, a0, sh_2);
+ ((op_t *) dstp)[1] = MERGE(a0, sh_1, a1, sh_2);
+ ((op_t *) dstp)[2] = MERGE(a1, sh_1, a2, sh_2);
+ ((op_t *) dstp)[3] = MERGE(a2, sh_1, a3, sh_2);
+
+ ap = a3;
+ srcp += 4 * OPSIZ;
+ dstp += 4 * OPSIZ;
+ len -= 4;
+ }
+ while (len > 0) {
+ register op_t a0;
+
+ a0 = ((op_t *) srcp)[0];
+ ((op_t *) dstp)[0] = MERGE(ap, sh_1, a0, sh_2);
+
+ ap = a0;
+ srcp += OPSIZ;
+ dstp += OPSIZ;
+ len -= 1;
+ }
+}
+
+void *memcpy(void *dstpp, const void *srcpp, size_t len)
+{
+ unsigned long int dstp = (long int) dstpp;
+ unsigned long int srcp = (long int) srcpp;
+
+ /* 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);
+
+ return dstpp;
+}
+
+void *memcpyb(void *dstpp, const void *srcpp, unsigned len)
+{
+ unsigned long int dstp = (long int) dstpp;
+ unsigned long int srcp = (long int) srcpp;
+
+ BYTE_COPY_FWD(dstp, srcp, len);
+
+ return dstpp;
+}