* libc/machine/aarch64/strcpy.S (strcpy): Further performance
improvements. Adjust to allow building as stpcpy. * libc/machine/aarch64/stpcpy.S: New file. * libc/machine/aarch64/stpcpy-stub.c: New file. * libc/machine/aarch64/Makefile.am (lib_a_SOURCES): Build stpcpy. * libc/machine/aarch64/Makefile.in: Regenerated.
This commit is contained in:
Richard Earnshaw
parent
ba913653a6
commit
6a35dbf342
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@ -1,3 +1,12 @@
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2015-01-06 Richard Earnshaw <rearnsha@arm.com>
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* libc/machine/aarch64/strcpy.S (strcpy): Further performance
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improvements. Adjust to allow building as stpcpy.
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* libc/machine/aarch64/stpcpy.S: New file.
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* libc/machine/aarch64/stpcpy-stub.c: New file.
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* libc/machine/aarch64/Makefile.am (lib_a_SOURCES): Build stpcpy.
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* libc/machine/aarch64/Makefile.in: Regenerated.
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2014-12-26 Freddie Chopin <freddie_chopin@op.pl>
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* libc/include/sys/features.h: update newlib version and copyright year
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@ -20,6 +20,8 @@ lib_a_SOURCES += memmove.S
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lib_a_SOURCES += memset-stub.c
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lib_a_SOURCES += memset.S
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lib_a_SOURCES += setjmp.S
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lib_a_SOURCES += stpcpy-stub.c
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lib_a_SOURCES += stpcpy.S
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lib_a_SOURCES += strchr-stub.c
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lib_a_SOURCES += strchr.S
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lib_a_SOURCES += strchrnul-stub.c
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@ -74,7 +74,8 @@ am_lib_a_OBJECTS = lib_a-memchr-stub.$(OBJEXT) lib_a-memchr.$(OBJEXT) \
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lib_a-memcpy-stub.$(OBJEXT) lib_a-memcpy.$(OBJEXT) \
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lib_a-memmove-stub.$(OBJEXT) lib_a-memmove.$(OBJEXT) \
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lib_a-memset-stub.$(OBJEXT) lib_a-memset.$(OBJEXT) \
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lib_a-setjmp.$(OBJEXT) lib_a-strchr-stub.$(OBJEXT) \
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lib_a-setjmp.$(OBJEXT) lib_a-stpcpy-stub.$(OBJEXT) \
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lib_a-stpcpy.$(OBJEXT) lib_a-strchr-stub.$(OBJEXT) \
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lib_a-strchr.$(OBJEXT) lib_a-strchrnul-stub.$(OBJEXT) \
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lib_a-strchrnul.$(OBJEXT) lib_a-strcmp-stub.$(OBJEXT) \
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lib_a-strcmp.$(OBJEXT) lib_a-strcpy-stub.$(OBJEXT) \
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@ -210,10 +211,10 @@ AM_CCASFLAGS = $(INCLUDES)
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noinst_LIBRARIES = lib.a
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lib_a_SOURCES = memchr-stub.c memchr.S memcmp-stub.c memcmp.S \
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memcpy-stub.c memcpy.S memmove-stub.c memmove.S memset-stub.c \
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memset.S setjmp.S strchr-stub.c strchr.S strchrnul-stub.c \
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strchrnul.S strcmp-stub.c strcmp.S strcpy-stub.c strcpy.S \
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strlen-stub.c strlen.S strncmp-stub.c strncmp.S strnlen-stub.c \
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strnlen.S strrchr-stub.c strrchr.S
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memset.S setjmp.S stpcpy-stub.c stpcpy.S strchr-stub.c \
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strchr.S strchrnul-stub.c strchrnul.S strcmp-stub.c strcmp.S \
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strcpy-stub.c strcpy.S strlen-stub.c strlen.S strncmp-stub.c \
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strncmp.S strnlen-stub.c strnlen.S strrchr-stub.c strrchr.S
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lib_a_CCASFLAGS = $(AM_CCASFLAGS)
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lib_a_CFLAGS = $(AM_CFLAGS)
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ACLOCAL_AMFLAGS = -I ../../.. -I ../../../..
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@ -312,6 +313,12 @@ lib_a-setjmp.o: setjmp.S
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lib_a-setjmp.obj: setjmp.S
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$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-setjmp.obj `if test -f 'setjmp.S'; then $(CYGPATH_W) 'setjmp.S'; else $(CYGPATH_W) '$(srcdir)/setjmp.S'; fi`
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lib_a-stpcpy.o: stpcpy.S
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$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-stpcpy.o `test -f 'stpcpy.S' || echo '$(srcdir)/'`stpcpy.S
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lib_a-stpcpy.obj: stpcpy.S
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$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-stpcpy.obj `if test -f 'stpcpy.S'; then $(CYGPATH_W) 'stpcpy.S'; else $(CYGPATH_W) '$(srcdir)/stpcpy.S'; fi`
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lib_a-strchr.o: strchr.S
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$(CCAS) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CCASFLAGS) $(CCASFLAGS) -c -o lib_a-strchr.o `test -f 'strchr.S' || echo '$(srcdir)/'`strchr.S
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@ -396,6 +403,12 @@ lib_a-memset-stub.o: memset-stub.c
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lib_a-memset-stub.obj: memset-stub.c
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$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-memset-stub.obj `if test -f 'memset-stub.c'; then $(CYGPATH_W) 'memset-stub.c'; else $(CYGPATH_W) '$(srcdir)/memset-stub.c'; fi`
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lib_a-stpcpy-stub.o: stpcpy-stub.c
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$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-stpcpy-stub.o `test -f 'stpcpy-stub.c' || echo '$(srcdir)/'`stpcpy-stub.c
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lib_a-stpcpy-stub.obj: stpcpy-stub.c
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$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-stpcpy-stub.obj `if test -f 'stpcpy-stub.c'; then $(CYGPATH_W) 'stpcpy-stub.c'; else $(CYGPATH_W) '$(srcdir)/stpcpy-stub.c'; fi`
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lib_a-strchr-stub.o: strchr-stub.c
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$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-strchr-stub.o `test -f 'strchr-stub.c' || echo '$(srcdir)/'`strchr-stub.c
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@ -0,0 +1,31 @@
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/* Copyright (c) 2015, ARM Limited
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All rights reserved.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
|
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* Redistributions of source code must retain the above copyright
|
||||
notice, this list of conditions and the following disclaimer.
|
||||
* Redistributions in binary form must reproduce the above copyright
|
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notice, this list of conditions and the following disclaimer in the
|
||||
documentation and/or other materials provided with the distribution.
|
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* Neither the name of the company nor the names of its contributors
|
||||
may be used to endorse or promote products derived from this
|
||||
software without specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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||||
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
||||
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
||||
HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||||
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
||||
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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||||
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
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#if (defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED))
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# include "../../string/stpcpy.c"
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#else
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/* See stpcpy.S */
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#endif
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@ -0,0 +1,34 @@
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/*
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stpcpy - copy a string returning pointer to end.
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Copyright (c) 2015 ARM Ltd.
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All Rights Reserved.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
|
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* Redistributions of source code must retain the above copyright
|
||||
notice, this list of conditions and the following disclaimer.
|
||||
* Redistributions in binary form must reproduce the above copyright
|
||||
notice, this list of conditions and the following disclaimer in the
|
||||
documentation and/or other materials provided with the distribution.
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* Neither the name of the company nor the names of its contributors
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||||
may be used to endorse or promote products derived from this
|
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software without specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||||
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
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A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
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HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||||
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
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DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
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THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
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/* This is just a wrapper that uses strcpy code with appropriate
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pre-defines. */
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#define BUILD_STPCPY
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#include "strcpy.S"
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@ -1,7 +1,7 @@
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/*
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strcpy - copy a string.
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strcpy/stpcpy - copy a string returning pointer to start/end.
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Copyright (c) 2013, 2014 ARM Ltd.
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Copyright (c) 2013, 2014, 2015 ARM Ltd.
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All Rights Reserved.
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Redistribution and use in source and binary forms, with or without
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@ -36,7 +36,9 @@
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* ARMv8-a, AArch64, unaligned accesses, min page size 4k.
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*/
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/* To test the page crossing code path more thoroughly, compile with
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/* To build as stpcpy, define BUILD_STPCPY before compiling this file.
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To test the page crossing code path more thoroughly, compile with
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-DSTRCPY_TEST_PAGE_CROSS - this will force all copies through the slower
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entry path. This option is not intended for production use. */
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@ -64,6 +66,12 @@
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#define len x16
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#define to_align x17
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#ifdef BUILD_STPCPY
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#define STRCPY stpcpy
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#else
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#define STRCPY strcpy
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#endif
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.macro def_fn f p2align=0
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.text
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.p2align \p2align
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@ -94,10 +102,16 @@
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misaligned, crosses a page boundary - after that we move to aligned
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fetches for the remainder of the string. */
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#ifdef STRCPY_TEST_PAGE_CROSS
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/* Make everything that isn't Qword aligned look like a page cross. */
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#define MIN_PAGE_P2 4
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#else
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#define MIN_PAGE_P2 12
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#endif
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#define MIN_PAGE_SIZE (1 << MIN_PAGE_P2)
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def_fn strcpy p2align=6
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def_fn STRCPY p2align=6
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/* For moderately short strings, the fastest way to do the copy is to
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calculate the length of the string in the same way as strlen, then
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essentially do a memcpy of the result. This avoids the need for
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@ -108,80 +122,112 @@ def_fn strcpy p2align=6
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always be difficult - we mitigate against this by preferring
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conditional select operations over branches whenever this is
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feasible. */
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add tmp2, srcin, #15
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and tmp2, srcin, #(MIN_PAGE_SIZE - 1)
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mov zeroones, #REP8_01
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and to_align, srcin, #15
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eor tmp2, tmp2, srcin
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mov dst, dstin
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cmp tmp2, #(MIN_PAGE_SIZE - 16)
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neg tmp1, to_align
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#ifdef STRCPY_TEST_PAGE_CROSS
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b .Lpage_cross
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#else
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/* The first fetch will straddle a (possible) page boundary iff
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srcin + 15 causes bit[MIN_PAGE_P2] to change value. A 16-byte
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aligned string will never fail the page align check, so will
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always take the fast path. */
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tbnz tmp2, #MIN_PAGE_P2, .Lpage_cross
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#endif
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b.gt .Lpage_cross
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.Lpage_cross_ok:
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ldp data1, data2, [srcin]
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add src, srcin, #16
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#ifdef __AARCH64EB__
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/* Because we expect the end to be found within 16 characters
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(profiling shows this is the most common case), it's worth
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swapping the bytes now to save having to recalculate the
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termination syndrome later. We preserve data1 and data2
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||||
so that we can re-use the values later on. */
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rev tmp2, data1
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sub tmp1, tmp2, zeroones
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orr tmp2, tmp2, #REP8_7f
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bics has_nul1, tmp1, tmp2
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b.ne .Lfp_le8
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||||
rev tmp4, data2
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sub tmp3, tmp4, zeroones
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orr tmp4, tmp4, #REP8_7f
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||||
#else
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||||
sub tmp1, data1, zeroones
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orr tmp2, data1, #REP8_7f
|
||||
bics has_nul1, tmp1, tmp2
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b.ne .Lfp_le8
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||||
sub tmp3, data2, zeroones
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orr tmp4, data2, #REP8_7f
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bic has_nul1, tmp1, tmp2
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||||
#endif
|
||||
bics has_nul2, tmp3, tmp4
|
||||
ccmp has_nul1, #0, #0, eq /* NZCV = 0000 */
|
||||
b.ne .Learly_end_found
|
||||
stp data1, data2, [dst], #16
|
||||
sub src, src, to_align
|
||||
sub dst, dst, to_align
|
||||
b.eq .Lbulk_entry
|
||||
|
||||
/* The string is short (<=16 bytes). We don't know exactly how
|
||||
short though, yet. Work out the exact length so that we can
|
||||
quickly select the optimal copy strategy. */
|
||||
.Lfp_gt8:
|
||||
rev has_nul2, has_nul2
|
||||
clz pos, has_nul2
|
||||
mov tmp2, #56
|
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add dst, dstin, pos, lsr #3 /* Bits to bytes. */
|
||||
sub pos, tmp2, pos
|
||||
#ifdef __AARCH64EB__
|
||||
lsr data2, data2, pos
|
||||
#else
|
||||
lsl data2, data2, pos
|
||||
#endif
|
||||
str data2, [dst, #1]
|
||||
str data1, [dstin]
|
||||
#ifdef BUILD_STPCPY
|
||||
add dstin, dst, #8
|
||||
#endif
|
||||
ret
|
||||
|
||||
.Lfp_le8:
|
||||
rev has_nul1, has_nul1
|
||||
clz pos, has_nul1
|
||||
add dst, dstin, pos, lsr #3 /* Bits to bytes. */
|
||||
subs tmp2, pos, #24 /* Pos in bits. */
|
||||
b.lt .Lfp_lt4
|
||||
#ifdef __AARCH64EB__
|
||||
mov tmp2, #56
|
||||
sub pos, tmp2, pos
|
||||
lsr data2, data1, pos
|
||||
lsr data1, data1, #32
|
||||
#else
|
||||
lsr data2, data1, tmp2
|
||||
#endif
|
||||
/* 4->7 bytes to copy. */
|
||||
str data2w, [dst, #-3]
|
||||
str data1w, [dstin]
|
||||
#ifdef BUILD_STPCPY
|
||||
mov dstin, dst
|
||||
#endif
|
||||
ret
|
||||
.Lfp_lt4:
|
||||
cbz pos, .Lfp_lt2
|
||||
/* 2->3 bytes to copy. */
|
||||
#ifdef __AARCH64EB__
|
||||
lsr data1, data1, #48
|
||||
#endif
|
||||
strh data1w, [dstin]
|
||||
/* Fall-through, one byte (max) to go. */
|
||||
.Lfp_lt2:
|
||||
/* Null-terminated string. Last character must be zero! */
|
||||
strb wzr, [dst]
|
||||
#ifdef BUILD_STPCPY
|
||||
mov dstin, dst
|
||||
#endif
|
||||
ret
|
||||
|
||||
.p2align 6
|
||||
/* Aligning here ensures that the entry code and main loop all lies
|
||||
within one 64-byte cache line. */
|
||||
.Lbulk_entry:
|
||||
sub to_align, to_align, #16
|
||||
stp data1, data2, [dstin]
|
||||
sub src, srcin, to_align
|
||||
sub dst, dstin, to_align
|
||||
b .Lentry_no_page_cross
|
||||
|
||||
.Lpage_cross:
|
||||
bic src, srcin, #15
|
||||
/* Start by loading two words at [srcin & ~15], then forcing the
|
||||
bytes that precede srcin to 0xff. This means they never look
|
||||
like termination bytes. */
|
||||
ldp data1, data2, [src], #16
|
||||
lsl tmp1, tmp1, #3 /* Bytes beyond alignment -> bits. */
|
||||
tst to_align, #7
|
||||
csetm tmp2, ne
|
||||
#ifdef __AARCH64EB__
|
||||
lsl tmp2, tmp2, tmp1 /* Shift (tmp1 & 63). */
|
||||
#else
|
||||
lsr tmp2, tmp2, tmp1 /* Shift (tmp1 & 63). */
|
||||
#endif
|
||||
orr data1, data1, tmp2
|
||||
orr data2a, data2, tmp2
|
||||
cmp to_align, #8
|
||||
csinv data1, data1, xzr, lt
|
||||
csel data2, data2, data2a, lt
|
||||
sub tmp1, data1, zeroones
|
||||
orr tmp2, data1, #REP8_7f
|
||||
sub tmp3, data2, zeroones
|
||||
orr tmp4, data2, #REP8_7f
|
||||
bic has_nul1, tmp1, tmp2
|
||||
bics has_nul2, tmp3, tmp4
|
||||
ccmp has_nul1, #0, #0, eq /* NZCV = 0000 */
|
||||
b.ne .Learly_end_found
|
||||
ldp data1, data2, [src], #16
|
||||
sub tmp1, data1, zeroones
|
||||
orr tmp2, data1, #REP8_7f
|
||||
sub tmp3, data2, zeroones
|
||||
orr tmp4, data2, #REP8_7f
|
||||
bic has_nul1, tmp1, tmp2
|
||||
bics has_nul2, tmp3, tmp4
|
||||
ccmp has_nul1, #0, #0, eq /* NZCV = 0000 */
|
||||
b.ne .Learly_end_found
|
||||
/* We've now checked between 16 and 32 bytes, but not found a null,
|
||||
so we can safely start bulk copying. Start by refetching the
|
||||
first 16 bytes of the real string; we know this can't trap now. */
|
||||
ldp data1a, data2a, [srcin]
|
||||
stp data1a, data2a, [dst], #16
|
||||
sub dst, dst, to_align
|
||||
/* Everything is now set up, so we can just fall into the bulk
|
||||
copy loop. */
|
||||
/* The inner loop deals with two Dwords at a time. This has a
|
||||
slightly higher start-up cost, but we should win quite quickly,
|
||||
especially on cores with a high number of issue slots per
|
||||
|
|
@ -225,72 +271,71 @@ def_fn strcpy p2align=6
|
|||
add dst, dst, pos, lsr #3
|
||||
ldp data1, data2, [src, #-32]
|
||||
stp data1, data2, [dst, #-16]
|
||||
#ifdef BUILD_STPCPY
|
||||
sub dstin, dst, #1
|
||||
#endif
|
||||
ret
|
||||
|
||||
/* The string is short (<32 bytes). We don't know exactly how
|
||||
short though, yet. Work out the exact length so that we can
|
||||
quickly select the optimal copy strategy. */
|
||||
.Learly_end_found:
|
||||
cmp has_nul1, #0
|
||||
.Lpage_cross:
|
||||
bic src, srcin, #15
|
||||
/* Start by loading two words at [srcin & ~15], then forcing the
|
||||
bytes that precede srcin to 0xff. This means they never look
|
||||
like termination bytes. */
|
||||
ldp data1, data2, [src]
|
||||
lsl tmp1, tmp1, #3 /* Bytes beyond alignment -> bits. */
|
||||
tst to_align, #7
|
||||
csetm tmp2, ne
|
||||
#ifdef __AARCH64EB__
|
||||
/* For big-endian, carry propagation (if the final byte in the
|
||||
string is 0x01) means we cannot use has_nul directly. The
|
||||
easiest way to get the correct byte is to byte-swap the data
|
||||
and calculate the syndrome a second time. */
|
||||
csel data1, data1, data2, ne
|
||||
rev data1, data1
|
||||
lsl tmp2, tmp2, tmp1 /* Shift (tmp1 & 63). */
|
||||
#else
|
||||
lsr tmp2, tmp2, tmp1 /* Shift (tmp1 & 63). */
|
||||
#endif
|
||||
orr data1, data1, tmp2
|
||||
orr data2a, data2, tmp2
|
||||
cmp to_align, #8
|
||||
csinv data1, data1, xzr, lt
|
||||
csel data2, data2, data2a, lt
|
||||
sub tmp1, data1, zeroones
|
||||
orr tmp2, data1, #REP8_7f
|
||||
sub tmp3, data2, zeroones
|
||||
orr tmp4, data2, #REP8_7f
|
||||
bic has_nul1, tmp1, tmp2
|
||||
bics has_nul2, tmp3, tmp4
|
||||
ccmp has_nul1, #0, #0, eq /* NZCV = 0000 */
|
||||
b.eq .Lpage_cross_ok
|
||||
/* We now need to make data1 and data2 look like they've been
|
||||
loaded directly from srcin. Do a rotate on the 128-bit value. */
|
||||
lsl tmp1, to_align, #3 /* Bytes->bits. */
|
||||
neg tmp2, to_align, lsl #3
|
||||
#ifdef __AARCH64EB__
|
||||
lsl data1a, data1, tmp1
|
||||
lsr tmp4, data2, tmp2
|
||||
lsl data2, data2, tmp1
|
||||
orr tmp4, tmp4, data1a
|
||||
cmp to_align, #8
|
||||
csel data1, tmp4, data2, lt
|
||||
rev tmp2, data1
|
||||
rev tmp4, data2
|
||||
sub tmp1, tmp2, zeroones
|
||||
orr tmp2, tmp2, #REP8_7f
|
||||
sub tmp3, tmp4, zeroones
|
||||
orr tmp4, tmp4, #REP8_7f
|
||||
#else
|
||||
csel has_nul1, has_nul1, has_nul2, ne
|
||||
lsr data1a, data1, tmp1
|
||||
lsl tmp4, data2, tmp2
|
||||
lsr data2, data2, tmp1
|
||||
orr tmp4, tmp4, data1a
|
||||
cmp to_align, #8
|
||||
csel data1, tmp4, data2, lt
|
||||
sub tmp1, data1, zeroones
|
||||
orr tmp2, data1, #REP8_7f
|
||||
sub tmp3, data2, zeroones
|
||||
orr tmp4, data2, #REP8_7f
|
||||
#endif
|
||||
rev has_nul1, has_nul1
|
||||
sub tmp1, src, #7
|
||||
sub src, src, #15
|
||||
clz pos, has_nul1
|
||||
csel src, src, tmp1, ne
|
||||
sub dst, dstin, srcin
|
||||
add src, src, pos, lsr #3 /* Bits to bytes. */
|
||||
add dst, dst, src
|
||||
sub len, src, srcin
|
||||
cmp len, #8
|
||||
b.lt .Llt8
|
||||
cmp len, #16
|
||||
b.lt .Llt16
|
||||
/* 16->32 bytes to copy. */
|
||||
ldp data1, data2, [srcin]
|
||||
ldp data1a, data2a, [src, #-16]
|
||||
stp data1, data2, [dstin]
|
||||
stp data1a, data2a, [dst, #-16]
|
||||
ret
|
||||
.Llt16:
|
||||
/* 8->15 bytes to copy. */
|
||||
ldr data1, [srcin]
|
||||
ldr data2, [src, #-8]
|
||||
str data1, [dstin]
|
||||
str data2, [dst, #-8]
|
||||
ret
|
||||
.Llt8:
|
||||
cmp len, #4
|
||||
b.lt .Llt4
|
||||
/* 4->7 bytes to copy. */
|
||||
ldr data1w, [srcin]
|
||||
ldr data2w, [src, #-4]
|
||||
str data1w, [dstin]
|
||||
str data2w, [dst, #-4]
|
||||
ret
|
||||
.Llt4:
|
||||
cmp len, #2
|
||||
b.lt .Llt2
|
||||
/* 2->3 bytes to copy. */
|
||||
ldrh data1w, [srcin]
|
||||
strh data1w, [dstin]
|
||||
/* Fall-through, one byte (max) to go. */
|
||||
.Llt2:
|
||||
/* Null-terminated string. Last character must be zero! */
|
||||
strb wzr, [dst, #-1]
|
||||
ret
|
||||
bic has_nul1, tmp1, tmp2
|
||||
cbnz has_nul1, .Lfp_le8
|
||||
bic has_nul2, tmp3, tmp4
|
||||
b .Lfp_gt8
|
||||
|
||||
.size strcpy, . - strcpy
|
||||
.size STRCPY, . - STRCPY
|
||||
#endif
|
||||
|
|
|
|||
Loading…
Reference in New Issue