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-rw-r--r--lib/memcopy.c403
1 files changed, 403 insertions, 0 deletions
diff --git a/lib/memcopy.c b/lib/memcopy.c
new file mode 100644
index 00000000000..d2d3376f738
--- /dev/null
+++ b/lib/memcopy.c
@@ -0,0 +1,403 @@
+/*
+ * memcopy.c -- subroutines for memory copy functions.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2.1 of the License, or (at your option)
+ * any later version.
+ *
+ * This program 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 General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * The code is derived from the GNU C Library.
+ * Copyright (C) 1991, 1992, 1993, 1997, 2004 Free Software Foundation, Inc.
+ */
+
+/* BE VERY CAREFUL IF YOU CHANGE THIS CODE...! */
+
+#include <linux/memcopy.h>
+
+/*
+ * _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.
+ */
+void _wordcopy_fwd_aligned (long int dstp, long int srcp, size_t len)
+{
+ op_t a0, a1;
+
+ switch (len % 8) {
+ case 2:
+ a0 = ((op_t *) srcp)[0];
+ srcp -= 6 * OPSIZ;
+ dstp -= 7 * OPSIZ;
+ len += 6;
+ goto do1;
+ case 3:
+ a1 = ((op_t *) srcp)[0];
+ srcp -= 5 * OPSIZ;
+ dstp -= 6 * OPSIZ;
+ len += 5;
+ goto do2;
+ case 4:
+ a0 = ((op_t *) srcp)[0];
+ srcp -= 4 * OPSIZ;
+ dstp -= 5 * OPSIZ;
+ len += 4;
+ goto do3;
+ case 5:
+ a1 = ((op_t *) srcp)[0];
+ srcp -= 3 * OPSIZ;
+ dstp -= 4 * OPSIZ;
+ len += 3;
+ goto do4;
+ case 6:
+ a0 = ((op_t *) srcp)[0];
+ srcp -= 2 * OPSIZ;
+ dstp -= 3 * OPSIZ;
+ len += 2;
+ goto do5;
+ case 7:
+ a1 = ((op_t *) srcp)[0];
+ srcp -= 1 * OPSIZ;
+ dstp -= 2 * OPSIZ;
+ len += 1;
+ goto do6;
+ case 0:
+ if (OP_T_THRESHOLD <= 3 * OPSIZ && len == 0)
+ return;
+ a0 = ((op_t *) srcp)[0];
+ srcp -= 0 * OPSIZ;
+ dstp -= 1 * OPSIZ;
+ goto do7;
+ case 1:
+ a1 = ((op_t *) srcp)[0];
+ srcp -=-1 * OPSIZ;
+ dstp -= 0 * OPSIZ;
+ len -= 1;
+ if (OP_T_THRESHOLD <= 3 * OPSIZ && len == 0)
+ goto do0;
+ goto do8; /* No-op. */
+ }
+
+ do {
+do8:
+ a0 = ((op_t *) srcp)[0];
+ ((op_t *) dstp)[0] = a1;
+do7:
+ a1 = ((op_t *) srcp)[1];
+ ((op_t *) dstp)[1] = a0;
+do6:
+ a0 = ((op_t *) srcp)[2];
+ ((op_t *) dstp)[2] = a1;
+do5:
+ a1 = ((op_t *) srcp)[3];
+ ((op_t *) dstp)[3] = a0;
+do4:
+ a0 = ((op_t *) srcp)[4];
+ ((op_t *) dstp)[4] = a1;
+do3:
+ a1 = ((op_t *) srcp)[5];
+ ((op_t *) dstp)[5] = a0;
+do2:
+ a0 = ((op_t *) srcp)[6];
+ ((op_t *) dstp)[6] = a1;
+do1:
+ a1 = ((op_t *) srcp)[7];
+ ((op_t *) dstp)[7] = a0;
+
+ srcp += 8 * OPSIZ;
+ dstp += 8 * OPSIZ;
+ len -= 8;
+ } while (len != 0);
+
+ /*
+ * This is the right position for do0. Please don't move it into
+ * the loop.
+ */
+do0:
+ ((op_t *) dstp)[0] = a1;
+}
+
+/*
+ * _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.
+ */
+
+void _wordcopy_fwd_dest_aligned (long int dstp, long int srcp, size_t len)
+{
+ op_t a0, a1, a2, a3;
+ 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;
+
+ switch (len % 4) {
+ case 2:
+ a1 = ((op_t *) srcp)[0];
+ a2 = ((op_t *) srcp)[1];
+ srcp -= 1 * OPSIZ;
+ dstp -= 3 * OPSIZ;
+ len += 2;
+ goto do1;
+ case 3:
+ a0 = ((op_t *) srcp)[0];
+ a1 = ((op_t *) srcp)[1];
+ srcp -= 0 * OPSIZ;
+ dstp -= 2 * OPSIZ;
+ len += 1;
+ goto do2;
+ case 0:
+ if (OP_T_THRESHOLD <= 3 * OPSIZ && len == 0)
+ return;
+ a3 = ((op_t *) srcp)[0];
+ a0 = ((op_t *) srcp)[1];
+ srcp -=-1 * OPSIZ;
+ dstp -= 1 * OPSIZ;
+ len += 0;
+ goto do3;
+ case 1:
+ a2 = ((op_t *) srcp)[0];
+ a3 = ((op_t *) srcp)[1];
+ srcp -=-2 * OPSIZ;
+ dstp -= 0 * OPSIZ;
+ len -= 1;
+ if (OP_T_THRESHOLD <= 3 * OPSIZ && len == 0)
+ goto do0;
+ goto do4; /* No-op. */
+ }
+
+ do {
+do4:
+ a0 = ((op_t *) srcp)[0];
+ ((op_t *) dstp)[0] = MERGE (a2, sh_1, a3, sh_2);
+do3:
+ a1 = ((op_t *) srcp)[1];
+ ((op_t *) dstp)[1] = MERGE (a3, sh_1, a0, sh_2);
+do2:
+ a2 = ((op_t *) srcp)[2];
+ ((op_t *) dstp)[2] = MERGE (a0, sh_1, a1, sh_2);
+do1:
+ a3 = ((op_t *) srcp)[3];
+ ((op_t *) dstp)[3] = MERGE (a1, sh_1, a2, sh_2);
+
+ srcp += 4 * OPSIZ;
+ dstp += 4 * OPSIZ;
+ len -= 4;
+ } while (len != 0);
+
+ /*
+ * This is the right position for do0. Please don't move it into
+ * the loop.
+ */
+do0:
+ ((op_t *) dstp)[0] = MERGE (a2, sh_1, a3, sh_2);
+}
+
+/*
+ * _wordcopy_bwd_aligned -- Copy block finishing right before
+ * SRCP to block finishing right before DSTP with LEN `op_t' words (not LEN
+ * bytes!). Both SRCP and DSTP should be aligned for memory operations
+ * on `op_t's.
+ */
+void _wordcopy_bwd_aligned (long int dstp, long int srcp, size_t len)
+{
+ op_t a0, a1;
+
+ switch (len % 8) {
+ case 2:
+ srcp -= 2 * OPSIZ;
+ dstp -= 1 * OPSIZ;
+ a0 = ((op_t *) srcp)[1];
+ len += 6;
+ goto do1;
+ case 3:
+ srcp -= 3 * OPSIZ;
+ dstp -= 2 * OPSIZ;
+ a1 = ((op_t *) srcp)[2];
+ len += 5;
+ goto do2;
+ case 4:
+ srcp -= 4 * OPSIZ;
+ dstp -= 3 * OPSIZ;
+ a0 = ((op_t *) srcp)[3];
+ len += 4;
+ goto do3;
+ case 5:
+ srcp -= 5 * OPSIZ;
+ dstp -= 4 * OPSIZ;
+ a1 = ((op_t *) srcp)[4];
+ len += 3;
+ goto do4;
+ case 6:
+ srcp -= 6 * OPSIZ;
+ dstp -= 5 * OPSIZ;
+ a0 = ((op_t *) srcp)[5];
+ len += 2;
+ goto do5;
+ case 7:
+ srcp -= 7 * OPSIZ;
+ dstp -= 6 * OPSIZ;
+ a1 = ((op_t *) srcp)[6];
+ len += 1;
+ goto do6;
+ case 0:
+ if (OP_T_THRESHOLD <= 3 * OPSIZ && len == 0)
+ return;
+ srcp -= 8 * OPSIZ;
+ dstp -= 7 * OPSIZ;
+ a0 = ((op_t *) srcp)[7];
+ goto do7;
+ case 1:
+ srcp -= 9 * OPSIZ;
+ dstp -= 8 * OPSIZ;
+ a1 = ((op_t *) srcp)[8];
+ len -= 1;
+ if (OP_T_THRESHOLD <= 3 * OPSIZ && len == 0)
+ goto do0;
+ goto do8; /* No-op. */
+ }
+
+ do {
+do8:
+ a0 = ((op_t *) srcp)[7];
+ ((op_t *) dstp)[7] = a1;
+do7:
+ a1 = ((op_t *) srcp)[6];
+ ((op_t *) dstp)[6] = a0;
+do6:
+ a0 = ((op_t *) srcp)[5];
+ ((op_t *) dstp)[5] = a1;
+do5:
+ a1 = ((op_t *) srcp)[4];
+ ((op_t *) dstp)[4] = a0;
+do4:
+ a0 = ((op_t *) srcp)[3];
+ ((op_t *) dstp)[3] = a1;
+do3:
+ a1 = ((op_t *) srcp)[2];
+ ((op_t *) dstp)[2] = a0;
+do2:
+ a0 = ((op_t *) srcp)[1];
+ ((op_t *) dstp)[1] = a1;
+do1:
+ a1 = ((op_t *) srcp)[0];
+ ((op_t *) dstp)[0] = a0;
+
+ srcp -= 8 * OPSIZ;
+ dstp -= 8 * OPSIZ;
+ len -= 8;
+ } while (len != 0);
+
+ /*
+ * This is the right position for do0. Please don't move it into
+ * the loop.
+ */
+do0:
+ ((op_t *) dstp)[7] = a1;
+}
+
+/*
+ * _wordcopy_bwd_dest_aligned -- Copy block finishing right before SRCP to
+ * block finishing right before DSTP with LEN `op_t' words (not LEN bytes!).
+ * DSTP should be aligned for memory operations on `op_t', but SRCP must *not*
+ * be aligned.
+ */
+void _wordcopy_bwd_dest_aligned (long int dstp, long int srcp, size_t len)
+{
+ op_t a0, a1, a2, a3;
+ 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;
+ srcp += OPSIZ;
+
+ switch (len % 4) {
+ case 2:
+ srcp -= 3 * OPSIZ;
+ dstp -= 1 * OPSIZ;
+ a2 = ((op_t *) srcp)[2];
+ a1 = ((op_t *) srcp)[1];
+ len += 2;
+ goto do1;
+ case 3:
+ srcp -= 4 * OPSIZ;
+ dstp -= 2 * OPSIZ;
+ a3 = ((op_t *) srcp)[3];
+ a2 = ((op_t *) srcp)[2];
+ len += 1;
+ goto do2;
+ case 0:
+ if (OP_T_THRESHOLD <= 3 * OPSIZ && len == 0)
+ return;
+ srcp -= 5 * OPSIZ;
+ dstp -= 3 * OPSIZ;
+ a0 = ((op_t *) srcp)[4];
+ a3 = ((op_t *) srcp)[3];
+ goto do3;
+ case 1:
+ srcp -= 6 * OPSIZ;
+ dstp -= 4 * OPSIZ;
+ a1 = ((op_t *) srcp)[5];
+ a0 = ((op_t *) srcp)[4];
+ len -= 1;
+ if (OP_T_THRESHOLD <= 3 * OPSIZ && len == 0)
+ goto do0;
+ goto do4; /* No-op. */
+ }
+
+ do {
+do4:
+ a3 = ((op_t *) srcp)[3];
+ ((op_t *) dstp)[3] = MERGE (a0, sh_1, a1, sh_2);
+do3:
+ a2 = ((op_t *) srcp)[2];
+ ((op_t *) dstp)[2] = MERGE (a3, sh_1, a0, sh_2);
+do2:
+ a1 = ((op_t *) srcp)[1];
+ ((op_t *) dstp)[1] = MERGE (a2, sh_1, a3, sh_2);
+do1:
+ a0 = ((op_t *) srcp)[0];
+ ((op_t *) dstp)[0] = MERGE (a1, sh_1, a2, sh_2);
+
+ srcp -= 4 * OPSIZ;
+ dstp -= 4 * OPSIZ;
+ len -= 4;
+ } while (len != 0);
+
+ /*
+ * This is the right position for do0. Please don't move it into
+ * the loop.
+ */
+do0:
+ ((op_t *) dstp)[3] = MERGE (a0, sh_1, a1, sh_2);
+}
+
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