From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/tile/lib/memcpy_64.c | 367 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 367 insertions(+) create mode 100644 arch/tile/lib/memcpy_64.c (limited to 'arch/tile/lib/memcpy_64.c') diff --git a/arch/tile/lib/memcpy_64.c b/arch/tile/lib/memcpy_64.c new file mode 100644 index 000000000..4815354b8 --- /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 +#include +#include +/* 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 -- cgit v1.2.3-54-g00ecf