diff options
author | Manuel Novoa III <mjn3@codepoet.org> | 2004-09-02 14:39:38 +0000 |
---|---|---|
committer | Manuel Novoa III <mjn3@codepoet.org> | 2004-09-02 14:39:38 +0000 |
commit | bec90733b9de6e7d75b8bda19b3f0a7117e6b78d (patch) | |
tree | 474ca0f3b80b7990ff33e547d42c1e7dc3014e3b /libc/string | |
parent | c4cedfc718426337b0215c256c184d2b4e20cd06 (diff) |
Add a couple of mips-specific string funcs.
Port the generic optimized string funcs from glibc, with some tweaks
to cut their size a little. The main change is making memmove
call memcpy for forward copying to trim redundant code.
Make use of both the generic and arch-specific speed-optimized string
funcs configurable. Arch-specific take precedence over generic,
and generic takes precedence over basic size-optimized uClibc funcs.
Diffstat (limited to 'libc/string')
34 files changed, 3706 insertions, 2 deletions
diff --git a/libc/string/Makefile b/libc/string/Makefile index 37a57cc26..02c86d6aa 100644 --- a/libc/string/Makefile +++ b/libc/string/Makefile @@ -20,10 +20,18 @@ TOPDIR=../../ include $(TOPDIR)Rules.mak DIRS= + +ifeq ($(UCLIBC_HAS_STRING_GENERIC_OPT),y) +DIRS += generic +endif + +ifeq ($(UCLIBC_HAS_STRING_ARCH_OPT),y) ifeq ($(TARGET_ARCH),$(wildcard $(TARGET_ARCH))) -DIRS = $(TARGET_ARCH) +DIRS += $(TARGET_ARCH) endif -ALL_SUBDIRS = arm frv i386 sh64 powerpc +endif + +ALL_SUBDIRS = generic arm frv i386 sh64 powerpc mips MSRC= wstring.c MOBJ= basename.o bcopy.o bzero.o dirname.o ffs.o memccpy.o memchr.o memcmp.o \ diff --git a/libc/string/generic/Makefile b/libc/string/generic/Makefile new file mode 100644 index 000000000..3f9af72a3 --- /dev/null +++ b/libc/string/generic/Makefile @@ -0,0 +1,48 @@ +# Makefile for uClibc +# +# Copyright (C) 2000-2003 Erik Andersen <andersen@uclibc.org> +# +# This program is free software; you can redistribute it and/or modify it under +# the terms of the GNU Library General Public License as published by the Free +# Software Foundation; either version 2 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 Library General Public License for more +# details. +# +# You should have received a copy of the GNU Library 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 + +TOPDIR=../../../ +include $(TOPDIR)Rules.mak + +CSRC= memchr.c memcmp.c memcpy.c memmem.c memmove.c mempcpy.c memrchr.c \ + memset.c rawmemchr.c strcat.c strchr.c strchrnul.c strcmp.c strcpy.c \ + strcspn.c strlen.c strncat.c strncmp.c strncpy.c strnlen.c \ + strrchr.c strsep.c strspn.c strstr.c strtok_r.c + +COBJS=$(patsubst %.c,%.o, $(CSRC)) + +OBJS=$(COBJS) + +all: $(OBJS) $(LIBC) + +$(LIBC): ar-target + +ar-target: $(OBJS) + $(AR) $(ARFLAGS) $(LIBC) $(OBJS) + +# $(MOBJ): $(MSRC) +# $(CC) $(CFLAGS) -DL_$* $< -c -o $*.o +# $(STRIPTOOL) -x -R .note -R .comment $*.o + +$(COBJS): %.o : %.c + $(CC) $(CFLAGS) -c $< -o $@ + $(STRIPTOOL) -x -R .note -R .comment $*.o + +clean: + $(RM) *.[oa] *~ core + diff --git a/libc/string/generic/bp-checks.h b/libc/string/generic/bp-checks.h new file mode 100644 index 000000000..efbb84716 --- /dev/null +++ b/libc/string/generic/bp-checks.h @@ -0,0 +1,129 @@ +/* Bounded-pointer checking macros for C. + Copyright (C) 2000 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Greg McGary <greg@mcgary.org> + + 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#ifndef _bp_checks_h_ +#define _bp_checks_h_ 1 + +#if __BOUNDED_POINTERS__ + +# define BOUNDS_VIOLATED (__builtin_trap (), 0) + +/* Verify that pointer's value >= low. Return pointer value. */ +# define CHECK_BOUNDS_LOW(ARG) \ + (((__ptrvalue (ARG) < __ptrlow (ARG)) && BOUNDS_VIOLATED), \ + __ptrvalue (ARG)) + +/* Verify that pointer's value < high. Return pointer value. */ +# define CHECK_BOUNDS_HIGH(ARG) \ + (((__ptrvalue (ARG) > __ptrhigh (ARG)) && BOUNDS_VIOLATED), \ + __ptrvalue (ARG)) + +# define _CHECK_N(ARG, N, COND) \ + (((COND) \ + && (__ptrvalue (ARG) < __ptrlow (ARG) \ + || __ptrvalue (ARG) + (N) > __ptrhigh (ARG)) \ + && BOUNDS_VIOLATED), \ + __ptrvalue (ARG)) + +extern void *__unbounded __ubp_memchr (const void *__unbounded, int, unsigned); + +# define _CHECK_STRING(ARG, COND) \ + (((COND) \ + && (__ptrvalue (ARG) < __ptrlow (ARG) \ + || !__ubp_memchr (__ptrvalue (ARG), '\0', \ + (__ptrhigh (ARG) - __ptrvalue (ARG)))) \ + && BOUNDS_VIOLATED), \ + __ptrvalue (ARG)) + +/* Check bounds of a pointer seated to an array of N objects. */ +# define CHECK_N(ARG, N) _CHECK_N ((ARG), (N), 1) +/* Same as CHECK_N, but tolerate ARG == NULL. */ +# define CHECK_N_NULL_OK(ARG, N) _CHECK_N ((ARG), (N), __ptrvalue (ARG)) + +/* Check bounds of a pointer seated to a single object. */ +# define CHECK_1(ARG) CHECK_N ((ARG), 1) +/* Same as CHECK_1, but tolerate ARG == NULL. */ +# define CHECK_1_NULL_OK(ARG) CHECK_N_NULL_OK ((ARG), 1) + +/* Check for NUL-terminator within string's bounds. */ +# define CHECK_STRING(ARG) _CHECK_STRING ((ARG), 1) +/* Same as CHECK_STRING, but tolerate ARG == NULL. */ +# define CHECK_STRING_NULL_OK(ARG) _CHECK_STRING ((ARG), __ptrvalue (ARG)) + +/* Check bounds of signal syscall args with type sigset_t. */ +# define CHECK_SIGSET(SET) CHECK_N ((SET), _NSIG / (8 * sizeof *(SET))) +/* Same as CHECK_SIGSET, but tolerate SET == NULL. */ +# define CHECK_SIGSET_NULL_OK(SET) CHECK_N_NULL_OK ((SET), _NSIG / (8 * sizeof *(SET))) + +# if defined (_IOC_SIZESHIFT) && defined (_IOC_SIZEBITS) +/* Extract the size of the ioctl data and check its bounds. */ +# define CHECK_IOCTL(ARG, CMD) \ + CHECK_N ((const char *) (ARG), \ + (((CMD) >> _IOC_SIZESHIFT) & ((1 << _IOC_SIZEBITS) - 1))) +# else +/* We don't know the size of the ioctl data, so the best we can do + is check that the first byte is within bounds. */ +# define CHECK_IOCTL(ARG, CMD) CHECK_1 ((const char *) ARG) +# endif + +/* Check bounds of `struct flock *' for the locking fcntl commands. */ +# define CHECK_FCNTL(ARG, CMD) \ + (((CMD) == F_GETLK || (CMD) == F_SETLK || (CMD) == F_SETLKW) \ + ? CHECK_1 ((struct flock *) ARG) : (unsigned long) (ARG)) + +/* Check bounds of an array of mincore residency-status flags that + cover a region of NBYTES. Such a vector occupies one byte per page + of memory. */ +# define CHECK_N_PAGES(ARG, NBYTES) \ + ({ int _page_size_ = sysconf (_SC_PAGE_SIZE); \ + CHECK_N ((const char *) (ARG), \ + ((NBYTES) + _page_size_ - 1) / _page_size_); }) + +/* Return a bounded pointer with value PTR that satisfies CHECK_N (PTR, N). */ +# define BOUNDED_N(PTR, N) \ + ({ __typeof (PTR) __bounded _p_; \ + __ptrvalue _p_ = __ptrlow _p_ = __ptrvalue (PTR); \ + __ptrhigh _p_ = __ptrvalue _p_ + (N); \ + _p_; }) + +#else /* !__BOUNDED_POINTERS__ */ + +/* Do nothing if not compiling with -fbounded-pointers. */ + +# define BOUNDS_VIOLATED +# define CHECK_BOUNDS_LOW(ARG) (ARG) +# define CHECK_BOUNDS_HIGH(ARG) (ARG) +# define CHECK_1(ARG) (ARG) +# define CHECK_1_NULL_OK(ARG) (ARG) +# define CHECK_N(ARG, N) (ARG) +# define CHECK_N_NULL_OK(ARG, N) (ARG) +# define CHECK_STRING(ARG) (ARG) +# define CHECK_SIGSET(SET) (SET) +# define CHECK_SIGSET_NULL_OK(SET) (SET) +# define CHECK_IOCTL(ARG, CMD) (ARG) +# define CHECK_FCNTL(ARG, CMD) (ARG) +# define CHECK_N_PAGES(ARG, NBYTES) (ARG) +# define BOUNDED_N(PTR, N) (PTR) + +#endif /* !__BOUNDED_POINTERS__ */ + +#define BOUNDED_1(PTR) BOUNDED_N (PTR, 1) + +#endif /* _bp_checks_h_ */ diff --git a/libc/string/generic/memchr.c b/libc/string/generic/memchr.c new file mode 100644 index 000000000..6116b8f92 --- /dev/null +++ b/libc/string/generic/memchr.c @@ -0,0 +1,175 @@ +/* Copyright (C) 1991,93,96,97,99,2000,2003 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Based on strlen implementation by Torbjorn Granlund (tege@sics.se), + with help from Dan Sahlin (dan@sics.se) and + commentary by Jim Blandy (jimb@ai.mit.edu); + adaptation to memchr suggested by Dick Karpinski (dick@cca.ucsf.edu), + and implemented by Roland McGrath (roland@ai.mit.edu). + + 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <string.h> +#include <stdlib.h> +#include <limits.h> + +#include "memcopy.h" + +#define LONG_MAX_32_BITS 2147483647 + +#undef memchr + +/* Search no more than N bytes of S for C. */ +void * memchr (const void * s, int c_in, size_t n) +{ + const unsigned char *char_ptr; + const unsigned long int *longword_ptr; + unsigned long int longword, magic_bits, charmask; + unsigned reg_char c; + + c = (unsigned char) c_in; + + /* Handle the first few characters by reading one character at a time. + Do this until CHAR_PTR is aligned on a longword boundary. */ + for (char_ptr = (const unsigned char *) s; + n > 0 && ((unsigned long int) char_ptr + & (sizeof (longword) - 1)) != 0; + --n, ++char_ptr) + if (*char_ptr == c) + return (void *) char_ptr; + + /* All these elucidatory comments refer to 4-byte longwords, + but the theory applies equally well to 8-byte longwords. */ + + longword_ptr = (unsigned long int *) char_ptr; + + /* Bits 31, 24, 16, and 8 of this number are zero. Call these bits + the "holes." Note that there is a hole just to the left of + each byte, with an extra at the end: + + bits: 01111110 11111110 11111110 11111111 + bytes: AAAAAAAA BBBBBBBB CCCCCCCC DDDDDDDD + + The 1-bits make sure that carries propagate to the next 0-bit. + The 0-bits provide holes for carries to fall into. */ + + if (sizeof (longword) != 4 && sizeof (longword) != 8) + abort (); + +#if LONG_MAX <= LONG_MAX_32_BITS + magic_bits = 0x7efefeff; +#else + magic_bits = ((unsigned long int) 0x7efefefe << 32) | 0xfefefeff; +#endif + + /* Set up a longword, each of whose bytes is C. */ + charmask = c | (c << 8); + charmask |= charmask << 16; +#if LONG_MAX > LONG_MAX_32_BITS + charmask |= charmask << 32; +#endif + + /* Instead of the traditional loop which tests each character, + we will test a longword at a time. The tricky part is testing + if *any of the four* bytes in the longword in question are zero. */ + while (n >= sizeof (longword)) + { + /* We tentatively exit the loop if adding MAGIC_BITS to + LONGWORD fails to change any of the hole bits of LONGWORD. + + 1) Is this safe? Will it catch all the zero bytes? + Suppose there is a byte with all zeros. Any carry bits + propagating from its left will fall into the hole at its + least significant bit and stop. Since there will be no + carry from its most significant bit, the LSB of the + byte to the left will be unchanged, and the zero will be + detected. + + 2) Is this worthwhile? Will it ignore everything except + zero bytes? Suppose every byte of LONGWORD has a bit set + somewhere. There will be a carry into bit 8. If bit 8 + is set, this will carry into bit 16. If bit 8 is clear, + one of bits 9-15 must be set, so there will be a carry + into bit 16. Similarly, there will be a carry into bit + 24. If one of bits 24-30 is set, there will be a carry + into bit 31, so all of the hole bits will be changed. + + The one misfire occurs when bits 24-30 are clear and bit + 31 is set; in this case, the hole at bit 31 is not + changed. If we had access to the processor carry flag, + we could close this loophole by putting the fourth hole + at bit 32! + + So it ignores everything except 128's, when they're aligned + properly. + + 3) But wait! Aren't we looking for C, not zero? + Good point. So what we do is XOR LONGWORD with a longword, + each of whose bytes is C. This turns each byte that is C + into a zero. */ + + longword = *longword_ptr++ ^ charmask; + + /* Add MAGIC_BITS to LONGWORD. */ + if ((((longword + magic_bits) + + /* Set those bits that were unchanged by the addition. */ + ^ ~longword) + + /* Look at only the hole bits. If any of the hole bits + are unchanged, most likely one of the bytes was a + zero. */ + & ~magic_bits) != 0) + { + /* Which of the bytes was C? If none of them were, it was + a misfire; continue the search. */ + + const unsigned char *cp = (const unsigned char *) (longword_ptr - 1); + + if (cp[0] == c) + return (void *) cp; + if (cp[1] == c) + return (void *) &cp[1]; + if (cp[2] == c) + return (void *) &cp[2]; + if (cp[3] == c) + return (void *) &cp[3]; +#if LONG_MAX > 2147483647 + if (cp[4] == c) + return (void *) &cp[4]; + if (cp[5] == c) + return (void *) &cp[5]; + if (cp[6] == c) + return (void *) &cp[6]; + if (cp[7] == c) + return (void *) &cp[7]; +#endif + } + + n -= sizeof (longword); + } + + char_ptr = (const unsigned char *) longword_ptr; + + while (n-- > 0) + { + if (*char_ptr == c) + return (void *) char_ptr; + else + ++char_ptr; + } + + return 0; +} diff --git a/libc/string/generic/memcmp.c b/libc/string/generic/memcmp.c new file mode 100644 index 000000000..d9c3a7cab --- /dev/null +++ b/libc/string/generic/memcmp.c @@ -0,0 +1,340 @@ +/* Copyright (C) 1991,1993,1995,1997,1998,2003,2004 + 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <string.h> + +#undef memcmp + +#include "memcopy.h" + +#include <endian.h> + +#if __BYTE_ORDER == __BIG_ENDIAN +# define WORDS_BIGENDIAN +#endif + +#ifdef WORDS_BIGENDIAN +# define CMP_LT_OR_GT(a, b) ((a) > (b) ? 1 : -1) +#else +# define CMP_LT_OR_GT(a, b) memcmp_bytes ((a), (b)) +#endif + +/* BE VERY CAREFUL IF YOU CHANGE THIS CODE! */ + +/* The strategy of this memcmp is: + + 1. Compare bytes until one of the block pointers is aligned. + + 2. Compare using memcmp_common_alignment or + memcmp_not_common_alignment, regarding the alignment of the other + block after the initial byte operations. The maximum number of + full words (of type op_t) are compared in this way. + + 3. Compare the few remaining bytes. */ + +#ifndef WORDS_BIGENDIAN +/* memcmp_bytes -- Compare A and B bytewise in the byte order of the machine. + A and B are known to be different. + This is needed only on little-endian machines. */ + +static int memcmp_bytes __P((op_t, op_t)); + +# ifdef __GNUC__ +__inline +# endif +static int +memcmp_bytes (a, b) + op_t a, b; +{ + long int srcp1 = (long int) &a; + long int srcp2 = (long int) &b; + op_t a0, b0; + + do + { + a0 = ((byte *) srcp1)[0]; + b0 = ((byte *) srcp2)[0]; + srcp1 += 1; + srcp2 += 1; + } + while (a0 == b0); + return a0 - b0; +} +#endif + +static int memcmp_common_alignment __P((long, long, size_t)); + +/* memcmp_common_alignment -- Compare blocks at SRCP1 and SRCP2 with LEN `op_t' + objects (not LEN bytes!). Both SRCP1 and SRCP2 should be aligned for + memory operations on `op_t's. */ +static int +memcmp_common_alignment (srcp1, srcp2, len) + long int srcp1; + long int srcp2; + size_t len; +{ + op_t a0, a1; + op_t b0, b1; + + switch (len % 4) + { + default: /* Avoid warning about uninitialized local variables. */ + case 2: + a0 = ((op_t *) srcp1)[0]; + b0 = ((op_t *) srcp2)[0]; + srcp1 -= 2 * OPSIZ; + srcp2 -= 2 * OPSIZ; + len += 2; + goto do1; + case 3: + a1 = ((op_t *) srcp1)[0]; + b1 = ((op_t *) srcp2)[0]; + srcp1 -= OPSIZ; + srcp2 -= OPSIZ; + len += 1; + goto do2; + case 0: + if (OP_T_THRES <= 3 * OPSIZ && len == 0) + return 0; + a0 = ((op_t *) srcp1)[0]; + b0 = ((op_t *) srcp2)[0]; + goto do3; + case 1: + a1 = ((op_t *) srcp1)[0]; + b1 = ((op_t *) srcp2)[0]; + srcp1 += OPSIZ; + srcp2 += OPSIZ; + len -= 1; + if (OP_T_THRES <= 3 * OPSIZ && len == 0) + goto do0; + /* Fall through. */ + } + + do + { + a0 = ((op_t *) srcp1)[0]; + b0 = ((op_t *) srcp2)[0]; + if (a1 != b1) + return CMP_LT_OR_GT (a1, b1); + + do3: + a1 = ((op_t *) srcp1)[1]; + b1 = ((op_t *) srcp2)[1]; + if (a0 != b0) + return CMP_LT_OR_GT (a0, b0); + + do2: + a0 = ((op_t *) srcp1)[2]; + b0 = ((op_t *) srcp2)[2]; + if (a1 != b1) + return CMP_LT_OR_GT (a1, b1); + + do1: + a1 = ((op_t *) srcp1)[3]; + b1 = ((op_t *) srcp2)[3]; + if (a0 != b0) + return CMP_LT_OR_GT (a0, b0); + + srcp1 += 4 * OPSIZ; + srcp2 += 4 * OPSIZ; + len -= 4; + } + while (len != 0); + + /* This is the right position for do0. Please don't move + it into the loop. */ + do0: + if (a1 != b1) + return CMP_LT_OR_GT (a1, b1); + return 0; +} + +static int memcmp_not_common_alignment __P((long, long, size_t)); + +/* memcmp_not_common_alignment -- Compare blocks at SRCP1 and SRCP2 with LEN + `op_t' objects (not LEN bytes!). SRCP2 should be aligned for memory + operations on `op_t', but SRCP1 *should be unaligned*. */ +static int +memcmp_not_common_alignment (srcp1, srcp2, len) + long int srcp1; + long int srcp2; + size_t len; +{ + op_t a0, a1, a2, a3; + op_t b0, b1, b2, b3; + op_t x; + int shl, shr; + + /* Calculate how to shift a word read at the memory operation + aligned srcp1 to make it aligned for comparison. */ + + shl = 8 * (srcp1 % OPSIZ); + shr = 8 * OPSIZ - shl; + + /* Make SRCP1 aligned by rounding it down to the beginning of the `op_t' + it points in the middle of. */ + srcp1 &= -OPSIZ; + + switch (len % 4) + { + default: /* Avoid warning about uninitialized local variables. */ + case 2: + a1 = ((op_t *) srcp1)[0]; + a2 = ((op_t *) srcp1)[1]; + b2 = ((op_t *) srcp2)[0]; + srcp1 -= 1 * OPSIZ; + srcp2 -= 2 * OPSIZ; + len += 2; + goto do1; + case 3: + a0 = ((op_t *) srcp1)[0]; + a1 = ((op_t *) srcp1)[1]; + b1 = ((op_t *) srcp2)[0]; + srcp2 -= 1 * OPSIZ; + len += 1; + goto do2; + case 0: + if (OP_T_THRES <= 3 * OPSIZ && len == 0) + return 0; + a3 = ((op_t *) srcp1)[0]; + a0 = ((op_t *) srcp1)[1]; + b0 = ((op_t *) srcp2)[0]; + srcp1 += 1 * OPSIZ; + goto do3; + case 1: + a2 = ((op_t *) srcp1)[0]; + a3 = ((op_t *) srcp1)[1]; + b3 = ((op_t *) srcp2)[0]; + srcp1 += 2 * OPSIZ; + srcp2 += 1 * OPSIZ; + len -= 1; + if (OP_T_THRES <= 3 * OPSIZ && len == 0) + goto do0; + /* Fall through. */ + } + + do + { + a0 = ((op_t *) srcp1)[0]; + b0 = ((op_t *) srcp2)[0]; + x = MERGE(a2, shl, a3, shr); + if (x != b3) + return CMP_LT_OR_GT (x, b3); + + do3: + a1 = ((op_t *) srcp1)[1]; + b1 = ((op_t *) srcp2)[1]; + x = MERGE(a3, shl, a0, shr); + if (x != b0) + return CMP_LT_OR_GT (x, b0); + + do2: + a2 = ((op_t *) srcp1)[2]; + b2 = ((op_t *) srcp2)[2]; + x = MERGE(a0, shl, a1, shr); + if (x != b1) + return CMP_LT_OR_GT (x, b1); + + do1: + a3 = ((op_t *) srcp1)[3]; + b3 = ((op_t *) srcp2)[3]; + x = MERGE(a1, shl, a2, shr); + if (x != b2) + return CMP_LT_OR_GT (x, b2); + + srcp1 += 4 * OPSIZ; + srcp2 += 4 * OPSIZ; + len -= 4; + } + while (len != 0); + + /* This is the right position for do0. Please don't move + it into the loop. */ + do0: + x = MERGE(a2, shl, a3, shr); + if (x != b3) + return CMP_LT_OR_GT (x, b3); + return 0; +} + +int +memcmp (s1, s2, len) + const __ptr_t s1; + const __ptr_t s2; + size_t len; +{ + op_t a0; + op_t b0; + long int srcp1 = (long int) s1; + long int srcp2 = (long int) s2; + op_t res; + + if (len >= OP_T_THRES) + { + /* There are at least some bytes to compare. No need to test + for LEN == 0 in this alignment loop. */ + while (srcp2 % OPSIZ != 0) + { + a0 = ((byte *) srcp1)[0]; + b0 = ((byte *) srcp2)[0]; + srcp1 += 1; + srcp2 += 1; + res = a0 - b0; + if (res != 0) + return res; + len -= 1; + } + + /* SRCP2 is now aligned for memory operations on `op_t'. + SRCP1 alignment determines if we can do a simple, + aligned compare or need to shuffle bits. */ + + if (srcp1 % OPSIZ == 0) + res = memcmp_common_alignment (srcp1, srcp2, len / OPSIZ); + else + res = memcmp_not_common_alignment (srcp1, srcp2, len / OPSIZ); + if (res != 0) + return res; + + /* Number of bytes remaining in the interval [0..OPSIZ-1]. */ + srcp1 += len & -OPSIZ; + srcp2 += len & -OPSIZ; + len %= OPSIZ; + } + + /* There are just a few bytes to compare. Use byte memory operations. */ + while (len != 0) + { + a0 = ((byte *) srcp1)[0]; + b0 = ((byte *) srcp2)[0]; + srcp1 += 1; + srcp2 += 1; + res = a0 - b0; + if (res != 0) + return res; + len -= 1; + } + + return 0; +} +#ifdef weak_alias +# undef bcmp +weak_alias (memcmp, bcmp) +#endif diff --git a/libc/string/generic/memcopy.h b/libc/string/generic/memcopy.h new file mode 100644 index 000000000..df1ba9a97 --- /dev/null +++ b/libc/string/generic/memcopy.h @@ -0,0 +1,150 @@ +/* memcopy.h -- definitions for memory copy functions. Generic C version. + Copyright (C) 1991, 1992, 1993, 1997 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +/* The strategy of the memory functions is: + + 1. Copy bytes until the destination pointer is aligned. + + 2. Copy words in unrolled loops. If the source and destination + are not aligned in the same way, use word memory operations, + but shift and merge two read words before writing. + + 3. Copy the few remaining bytes. + + This is fast on processors that have at least 10 registers for + allocation by GCC, and that can access memory at reg+const in one + instruction. + + I made an "exhaustive" test of this memmove when I wrote it, + exhaustive in the sense that I tried all alignment and length + combinations, with and without overlap. */ + +#include <sys/cdefs.h> +#include <endian.h> + +/* The macros defined in this file are: + + BYTE_COPY_FWD(dst_beg_ptr, src_beg_ptr, nbytes_to_copy) + + BYTE_COPY_BWD(dst_end_ptr, src_end_ptr, nbytes_to_copy) + + WORD_COPY_FWD(dst_beg_ptr, src_beg_ptr, nbytes_remaining, nbytes_to_copy) + + WORD_COPY_BWD(dst_end_ptr, src_end_ptr, nbytes_remaining, nbytes_to_copy) + + MERGE(old_word, sh_1, new_word, sh_2) + [I fail to understand. I feel stupid. --roland] +*/ + +/* 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)) + +/* Type to use for unaligned operations. */ +typedef unsigned char byte; + |