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Diffstat (limited to 'arch/tile/lib/memcpy_64.c')
-rw-r--r--arch/tile/lib/memcpy_64.c367
1 files changed, 367 insertions, 0 deletions
diff --git a/arch/tile/lib/memcpy_64.c b/arch/tile/lib/memcpy_64.c
new file mode 100644
index 00000000000..4815354b8cd
--- /dev/null
+++ b/arch/tile/lib/memcpy_64.c
@@ -0,0 +1,367 @@
+/*
+ * Copyright 2011 Tilera Corporation. All Rights Reserved.
+ *
+ * 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, version 2.
+ *
+ * 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, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/module.h>
+/* EXPORT_SYMBOL() is in arch/tile/lib/exports.c since this should be asm. */
+
+/* Must be 8 bytes in size. */
+#define op_t uint64_t
+
+/* Threshold value for when to enter the unrolled loops. */
+#define OP_T_THRES 16
+
+#if CHIP_L2_LINE_SIZE() != 64
+#error "Assumes 64 byte line size"
+#endif
+
+/* How many cache lines ahead should we prefetch? */
+#define PREFETCH_LINES_AHEAD 4
+
+/*
+ * Provide "base versions" of load and store for the normal code path.
+ * The kernel provides other versions for userspace copies.
+ */
+#define ST(p, v) (*(p) = (v))
+#define LD(p) (*(p))
+
+#ifndef USERCOPY_FUNC
+#define ST1 ST
+#define ST2 ST
+#define ST4 ST
+#define ST8 ST
+#define LD1 LD
+#define LD2 LD
+#define LD4 LD
+#define LD8 LD
+#define RETVAL dstv
+void *memcpy(void *__restrict dstv, const void *__restrict srcv, size_t n)
+#else
+/*
+ * Special kernel version will provide implementation of the LDn/STn
+ * macros to return a count of uncopied bytes due to mm fault.
+ */
+#define RETVAL 0
+int __attribute__((optimize("omit-frame-pointer")))
+USERCOPY_FUNC(void *__restrict dstv, const void *__restrict srcv, size_t n)
+#endif
+{
+ char *__restrict dst1 = (char *)dstv;
+ const char *__restrict src1 = (const char *)srcv;
+ const char *__restrict src1_end;
+ const char *__restrict prefetch;
+ op_t *__restrict dst8; /* 8-byte pointer to destination memory. */
+ op_t final; /* Final bytes to write to trailing word, if any */
+ long i;
+
+ if (n < 16) {
+ for (; n; n--)
+ ST1(dst1++, LD1(src1++));
+ return RETVAL;
+ }
+
+ /*
+ * Locate the end of source memory we will copy. Don't
+ * prefetch past this.
+ */
+ src1_end = src1 + n - 1;
+
+ /* Prefetch ahead a few cache lines, but not past the end. */
+ prefetch = src1;
+ for (i = 0; i < PREFETCH_LINES_AHEAD; i++) {
+ __insn_prefetch(prefetch);
+ prefetch += CHIP_L2_LINE_SIZE();
+ prefetch = (prefetch < src1_end) ? prefetch : src1;
+ }
+
+ /* Copy bytes until dst is word-aligned. */
+ for (; (uintptr_t)dst1 & (sizeof(op_t) - 1); n--)
+ ST1(dst1++, LD1(src1++));
+
+ /* 8-byte pointer to destination memory. */
+ dst8 = (op_t *)dst1;
+
+ if (__builtin_expect((uintptr_t)src1 & (sizeof(op_t) - 1), 0)) {
+ /* Unaligned copy. */
+
+ op_t tmp0 = 0, tmp1 = 0, tmp2, tmp3;
+ const op_t *src8 = (const op_t *) ((uintptr_t)src1 &
+ -sizeof(op_t));
+ const void *srci = (void *)src1;
+ int m;
+
+ m = (CHIP_L2_LINE_SIZE() << 2) -
+ (((uintptr_t)dst8) & ((CHIP_L2_LINE_SIZE() << 2) - 1));
+ m = (n < m) ? n : m;
+ m /= sizeof(op_t);
+
+ /* Copy until 'dst' is cache-line-aligned. */
+ n -= (sizeof(op_t) * m);
+
+ switch (m % 4) {
+ case 0:
+ if (__builtin_expect(!m, 0))
+ goto _M0;
+ tmp1 = LD8(src8++);
+ tmp2 = LD8(src8++);
+ goto _8B3;
+ case 2:
+ m += 2;
+ tmp3 = LD8(src8++);
+ tmp0 = LD8(src8++);
+ goto _8B1;
+ case 3:
+ m += 1;
+ tmp2 = LD8(src8++);
+ tmp3 = LD8(src8++);
+ goto _8B2;
+ case 1:
+ m--;
+ tmp0 = LD8(src8++);
+ tmp1 = LD8(src8++);
+ if (__builtin_expect(!m, 0))
+ goto _8B0;
+ }
+
+ do {
+ tmp2 = LD8(src8++);
+ tmp0 = __insn_dblalign(tmp0, tmp1, srci);
+ ST8(dst8++, tmp0);
+_8B3:
+ tmp3 = LD8(src8++);
+ tmp1 = __insn_dblalign(tmp1, tmp2, srci);
+ ST8(dst8++, tmp1);
+_8B2:
+ tmp0 = LD8(src8++);
+ tmp2 = __insn_dblalign(tmp2, tmp3, srci);
+ ST8(dst8++, tmp2);
+_8B1:
+ tmp1 = LD8(src8++);
+ tmp3 = __insn_dblalign(tmp3, tmp0, srci);
+ ST8(dst8++, tmp3);
+ m -= 4;
+ } while (m);
+
+_8B0:
+ tmp0 = __insn_dblalign(tmp0, tmp1, srci);
+ ST8(dst8++, tmp0);
+ src8--;
+
+_M0:
+ if (__builtin_expect(n >= CHIP_L2_LINE_SIZE(), 0)) {
+ op_t tmp4, tmp5, tmp6, tmp7, tmp8;
+
+ prefetch = ((const char *)src8) +
+ CHIP_L2_LINE_SIZE() * PREFETCH_LINES_AHEAD;
+
+ for (tmp0 = LD8(src8++); n >= CHIP_L2_LINE_SIZE();
+ n -= CHIP_L2_LINE_SIZE()) {
+ /* Prefetch and advance to next line to
+ prefetch, but don't go past the end. */
+ __insn_prefetch(prefetch);
+
+ /* Make sure prefetch got scheduled
+ earlier. */
+ __asm__ ("" : : : "memory");
+
+ prefetch += CHIP_L2_LINE_SIZE();
+ prefetch = (prefetch < src1_end) ? prefetch :
+ (const char *) src8;
+
+ tmp1 = LD8(src8++);
+ tmp2 = LD8(src8++);
+ tmp3 = LD8(src8++);
+ tmp4 = LD8(src8++);
+ tmp5 = LD8(src8++);
+ tmp6 = LD8(src8++);
+ tmp7 = LD8(src8++);
+ tmp8 = LD8(src8++);
+
+ tmp0 = __insn_dblalign(tmp0, tmp1, srci);
+ tmp1 = __insn_dblalign(tmp1, tmp2, srci);
+ tmp2 = __insn_dblalign(tmp2, tmp3, srci);
+ tmp3 = __insn_dblalign(tmp3, tmp4, srci);
+ tmp4 = __insn_dblalign(tmp4, tmp5, srci);
+ tmp5 = __insn_dblalign(tmp5, tmp6, srci);
+ tmp6 = __insn_dblalign(tmp6, tmp7, srci);
+ tmp7 = __insn_dblalign(tmp7, tmp8, srci);
+
+ __insn_wh64(dst8);
+
+ ST8(dst8++, tmp0);
+ ST8(dst8++, tmp1);
+ ST8(dst8++, tmp2);
+ ST8(dst8++, tmp3);
+ ST8(dst8++, tmp4);
+ ST8(dst8++, tmp5);
+ ST8(dst8++, tmp6);
+ ST8(dst8++, tmp7);
+
+ tmp0 = tmp8;
+ }
+ src8--;
+ }
+
+ /* Copy the rest 8-byte chunks. */
+ if (n >= sizeof(op_t)) {
+ tmp0 = LD8(src8++);
+ for (; n >= sizeof(op_t); n -= sizeof(op_t)) {
+ tmp1 = LD8(src8++);
+ tmp0 = __insn_dblalign(tmp0, tmp1, srci);
+ ST8(dst8++, tmp0);
+ tmp0 = tmp1;
+ }
+ src8--;
+ }
+
+ if (n == 0)
+ return RETVAL;
+
+ tmp0 = LD8(src8++);
+ tmp1 = ((const char *)src8 <= src1_end)
+ ? LD8((op_t *)src8) : 0;
+ final = __insn_dblalign(tmp0, tmp1, srci);
+
+ } else {
+ /* Aligned copy. */
+
+ const op_t *__restrict src8 = (const op_t *)src1;
+
+ /* src8 and dst8 are both word-aligned. */
+ if (n >= CHIP_L2_LINE_SIZE()) {
+ /* Copy until 'dst' is cache-line-aligned. */
+ for (; (uintptr_t)dst8 & (CHIP_L2_LINE_SIZE() - 1);
+ n -= sizeof(op_t))
+ ST8(dst8++, LD8(src8++));
+
+ for (; n >= CHIP_L2_LINE_SIZE(); ) {
+ op_t tmp0, tmp1, tmp2, tmp3;
+ op_t tmp4, tmp5, tmp6, tmp7;
+
+ /*
+ * Prefetch and advance to next line
+ * to prefetch, but don't go past the
+ * end.
+ */
+ __insn_prefetch(prefetch);
+
+ /* Make sure prefetch got scheduled
+ earlier. */
+ __asm__ ("" : : : "memory");
+
+ prefetch += CHIP_L2_LINE_SIZE();
+ prefetch = (prefetch < src1_end) ? prefetch :
+ (const char *)src8;
+
+ /*
+ * Do all the loads before wh64. This
+ * is necessary if [src8, src8+7] and
+ * [dst8, dst8+7] share the same cache
+ * line and dst8 <= src8, as can be
+ * the case when called from memmove,
+ * or with code tested on x86 whose
+ * memcpy always works with forward
+ * copies.
+ */
+ tmp0 = LD8(src8++);
+ tmp1 = LD8(src8++);
+ tmp2 = LD8(src8++);
+ tmp3 = LD8(src8++);
+ tmp4 = LD8(src8++);
+ tmp5 = LD8(src8++);
+ tmp6 = LD8(src8++);
+ tmp7 = LD8(src8++);
+
+ /* wh64 and wait for tmp7 load completion. */
+ __asm__ ("move %0, %0; wh64 %1\n"
+ : : "r"(tmp7), "r"(dst8));
+
+ ST8(dst8++, tmp0);
+ ST8(dst8++, tmp1);
+ ST8(dst8++, tmp2);
+ ST8(dst8++, tmp3);
+ ST8(dst8++, tmp4);
+ ST8(dst8++, tmp5);
+ ST8(dst8++, tmp6);
+ ST8(dst8++, tmp7);
+
+ n -= CHIP_L2_LINE_SIZE();
+ }
+#if CHIP_L2_LINE_SIZE() != 64
+# error "Fix code that assumes particular L2 cache line size."
+#endif
+ }
+
+ for (; n >= sizeof(op_t); n -= sizeof(op_t))
+ ST8(dst8++, LD8(src8++));
+
+ if (__builtin_expect(n == 0, 1))
+ return RETVAL;
+
+ final = LD8(src8);
+ }
+
+ /* n != 0 if we get here. Write out any trailing bytes. */
+ dst1 = (char *)dst8;
+#ifndef __BIG_ENDIAN__
+ if (n & 4) {
+ ST4((uint32_t *)dst1, final);
+ dst1 += 4;
+ final >>= 32;
+ n &= 3;
+ }
+ if (n & 2) {
+ ST2((uint16_t *)dst1, final);
+ dst1 += 2;
+ final >>= 16;
+ n &= 1;
+ }
+ if (n)
+ ST1((uint8_t *)dst1, final);
+#else
+ if (n & 4) {
+ ST4((uint32_t *)dst1, final >> 32);
+ dst1 += 4;
+ }
+ else
+ {
+ final >>= 32;
+ }
+ if (n & 2) {
+ ST2((uint16_t *)dst1, final >> 16);
+ dst1 += 2;
+ }
+ else
+ {
+ final >>= 16;
+ }
+ if (n & 1)
+ ST1((uint8_t *)dst1, final >> 8);
+#endif
+
+ return RETVAL;
+}
+
+#ifdef USERCOPY_FUNC
+#undef ST1
+#undef ST2
+#undef ST4
+#undef ST8
+#undef LD1
+#undef LD2
+#undef LD4
+#undef LD8
+#undef USERCOPY_FUNC
+#endif
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