From 1efea40d4172a2a475ccb29b59d6221e9d0c174b Mon Sep 17 00:00:00 2001 From: Chris Metcalf Date: Thu, 29 Mar 2012 13:30:31 -0400 Subject: arch/tile: support building big-endian kernel The toolchain supports big-endian mode now, so add support for building the kernel to run big-endian as well. Signed-off-by: Chris Metcalf --- arch/tile/lib/memchr_64.c | 8 +++----- arch/tile/lib/memcpy_64.c | 23 +++++++++++++++++++++-- arch/tile/lib/strchr_64.c | 15 +++++---------- arch/tile/lib/string-endian.h | 33 +++++++++++++++++++++++++++++++++ arch/tile/lib/strlen_64.c | 11 ++++------- 5 files changed, 66 insertions(+), 24 deletions(-) create mode 100644 arch/tile/lib/string-endian.h (limited to 'arch/tile/lib') diff --git a/arch/tile/lib/memchr_64.c b/arch/tile/lib/memchr_64.c index 84fdc8d8e735..6f867dbf7c56 100644 --- a/arch/tile/lib/memchr_64.c +++ b/arch/tile/lib/memchr_64.c @@ -15,6 +15,7 @@ #include #include #include +#include "string-endian.h" void *memchr(const void *s, int c, size_t n) { @@ -39,11 +40,8 @@ void *memchr(const void *s, int c, size_t n) /* Read the first word, but munge it so that bytes before the array * will not match goal. - * - * Note that this shift count expression works because we know - * shift counts are taken mod 64. */ - before_mask = (1ULL << (s_int << 3)) - 1; + before_mask = MASK(s_int); v = (*p | before_mask) ^ (goal & before_mask); /* Compute the address of the last byte. */ @@ -65,7 +63,7 @@ void *memchr(const void *s, int c, size_t n) /* We found a match, but it might be in a byte past the end * of the array. */ - ret = ((char *)p) + (__insn_ctz(bits) >> 3); + ret = ((char *)p) + (CFZ(bits) >> 3); return (ret <= last_byte_ptr) ? ret : NULL; } EXPORT_SYMBOL(memchr); diff --git a/arch/tile/lib/memcpy_64.c b/arch/tile/lib/memcpy_64.c index 3fab9a6a2bbe..c79b8e7c6828 100644 --- a/arch/tile/lib/memcpy_64.c +++ b/arch/tile/lib/memcpy_64.c @@ -15,7 +15,6 @@ #include #include #include -#define __memcpy memcpy /* EXPORT_SYMBOL() is in arch/tile/lib/exports.c since this should be asm. */ /* Must be 8 bytes in size. */ @@ -188,6 +187,7 @@ int USERCOPY_FUNC(void *__restrict dstv, const void *__restrict srcv, size_t n) /* 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; @@ -202,11 +202,30 @@ int USERCOPY_FUNC(void *__restrict dstv, const void *__restrict srcv, size_t n) } 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 diff --git a/arch/tile/lib/strchr_64.c b/arch/tile/lib/strchr_64.c index 617a9273aaa8..f39f9dc422b0 100644 --- a/arch/tile/lib/strchr_64.c +++ b/arch/tile/lib/strchr_64.c @@ -15,8 +15,7 @@ #include #include #include - -#undef strchr +#include "string-endian.h" char *strchr(const char *s, int c) { @@ -33,13 +32,9 @@ char *strchr(const char *s, int c) * match neither zero nor goal (we make sure the high bit of each * byte is 1, and the low 7 bits are all the opposite of the goal * byte). - * - * Note that this shift count expression works because we know shift - * counts are taken mod 64. */ - const uint64_t before_mask = (1ULL << (s_int << 3)) - 1; - uint64_t v = (*p | before_mask) ^ - (goal & __insn_v1shrsi(before_mask, 1)); + const uint64_t before_mask = MASK(s_int); + uint64_t v = (*p | before_mask) ^ (goal & __insn_v1shrui(before_mask, 1)); uint64_t zero_matches, goal_matches; while (1) { @@ -55,8 +50,8 @@ char *strchr(const char *s, int c) v = *++p; } - z = __insn_ctz(zero_matches); - g = __insn_ctz(goal_matches); + z = CFZ(zero_matches); + g = CFZ(goal_matches); /* If we found c before '\0' we got a match. Note that if c == '\0' * then g == z, and we correctly return the address of the '\0' diff --git a/arch/tile/lib/string-endian.h b/arch/tile/lib/string-endian.h new file mode 100644 index 000000000000..c0eed7ce69c3 --- /dev/null +++ b/arch/tile/lib/string-endian.h @@ -0,0 +1,33 @@ +/* + * 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. + * + * Provide a mask based on the pointer alignment that + * sets up non-zero bytes before the beginning of the string. + * The MASK expression works because shift counts are taken mod 64. + * Also, specify how to count "first" and "last" bits + * when the bits have been read as a word. + */ + +#include + +#ifdef __LITTLE_ENDIAN +#define MASK(x) (__insn_shl(1ULL, (x << 3)) - 1) +#define NULMASK(x) ((2ULL << x) - 1) +#define CFZ(x) __insn_ctz(x) +#define REVCZ(x) __insn_clz(x) +#else +#define MASK(x) (__insn_shl(-2LL, ((-x << 3) - 1))) +#define NULMASK(x) (-2LL << (63 - x)) +#define CFZ(x) __insn_clz(x) +#define REVCZ(x) __insn_ctz(x) +#endif diff --git a/arch/tile/lib/strlen_64.c b/arch/tile/lib/strlen_64.c index 1c92d46202a8..9583fc3361fa 100644 --- a/arch/tile/lib/strlen_64.c +++ b/arch/tile/lib/strlen_64.c @@ -15,8 +15,7 @@ #include #include #include - -#undef strlen +#include "string-endian.h" size_t strlen(const char *s) { @@ -24,15 +23,13 @@ size_t strlen(const char *s) const uintptr_t s_int = (uintptr_t) s; const uint64_t *p = (const uint64_t *)(s_int & -8); - /* Read the first word, but force bytes before the string to be nonzero. - * This expression works because we know shift counts are taken mod 64. - */ - uint64_t v = *p | ((1ULL << (s_int << 3)) - 1); + /* Read and MASK the first word. */ + uint64_t v = *p | MASK(s_int); uint64_t bits; while ((bits = __insn_v1cmpeqi(v, 0)) == 0) v = *++p; - return ((const char *)p) + (__insn_ctz(bits) >> 3) - s; + return ((const char *)p) + (CFZ(bits) >> 3) - s; } EXPORT_SYMBOL(strlen); -- cgit v1.2.1