svn commit: trunk/uClibc/libc/string/cris
pkj at uclibc.org
pkj at uclibc.org
Fri Sep 26 14:37:08 UTC 2008
Author: pkj
Date: 2008-09-26 07:37:08 -0700 (Fri, 26 Sep 2008)
New Revision: 23520
Log:
Rebased the memcpy() and memset() implementations for CRIS on the versions
found in newlib rather than the ones found in glibc. This should make them
smaller and (hopefully) make them compile with newer versions of gcc.
Modified:
trunk/uClibc/libc/string/cris/memcpy.c
trunk/uClibc/libc/string/cris/memset.c
Changeset:
Modified: trunk/uClibc/libc/string/cris/memcpy.c
===================================================================
--- trunk/uClibc/libc/string/cris/memcpy.c 2008-09-26 14:10:17 UTC (rev 23519)
+++ trunk/uClibc/libc/string/cris/memcpy.c 2008-09-26 14:37:08 UTC (rev 23520)
@@ -1,264 +1,243 @@
-/* Copyright (C) 2001, 2003 Free Software Foundation, Inc.
- Copyright (C) 1994, 1995, 2000 Axis Communications AB.
+/* A memcpy for CRIS.
+ Copyright (C) 1994-2008 Axis Communications.
+ All rights reserved.
- This file is part of the GNU C Library.
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
- The GNU C Library 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.
+ 1. Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
- 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
- Library General Public License for more details.
+ 2. Neither the name of Axis Communications nor the names of its
+ contributors may be used to endorse or promote products derived
+ from this software without specific prior written permission.
- You should have received a copy of the GNU Library General Public
- License along with the GNU C Library; see the file COPYING.LIB. If not,
- write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ THIS SOFTWARE IS PROVIDED BY AXIS COMMUNICATIONS AND ITS CONTRIBUTORS
+ ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL AXIS
+ COMMUNICATIONS OR ITS 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, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ POSSIBILITY OF SUCH DAMAGE. */
-/*#************************************************************************#*/
-/*#-------------------------------------------------------------------------*/
-/*# */
-/*# FUNCTION NAME: memcpy() */
-/*# */
-/*# PARAMETERS: void* dst; Destination address. */
-/*# void* src; Source address. */
-/*# int len; Number of bytes to copy. */
-/*# */
-/*# RETURNS: dst. */
-/*# */
-/*# DESCRIPTION: Copies len bytes of memory from src to dst. No guarantees */
-/*# about copying of overlapping memory areas. This routine is */
-/*# very sensitive to compiler changes in register allocation. */
-/*# Should really be rewritten to avoid this problem. */
-/*# */
-/*#-------------------------------------------------------------------------*/
-/*# */
-/*# HISTORY */
-/*# */
-/*# DATE NAME CHANGES */
-/*# ---- ---- ------- */
-/*# 941007 Kenny R Creation */
-/*# 941011 Kenny R Lots of optimizations and inlining. */
-/*# 941129 Ulf A Adapted for use in libc. */
-/*# 950216 HP N==0 forgotten if non-aligned src/dst. */
-/*# Added some optimizations. */
-/*# 001025 HP Make src and dst char *. Align dst to */
-/*# dword, not just word-if-both-src-and-dst- */
-/*# are-misaligned. */
-/*# 070806 RW Modified for uClibc */
-/*# (__arch_v32 -> __CONFIG_CRISV32__, */
-/*# include features.h to reach it.) */
-/*# */
-/*#-------------------------------------------------------------------------*/
+/* FIXME: This file should really only be used for reference, as the
+ result is somewhat depending on gcc generating what we expect rather
+ than what we describe. An assembly file should be used instead. */
-#include <features.h>
+#include <string.h>
-#ifdef __CONFIG_CRISV32__
+#ifdef __arch_v32
/* For CRISv32, movem is very cheap. */
-#define MEMCPY_BLOCK_THRESHOLD (44)
+#define MEMCPY_BY_BLOCK_THRESHOLD (44)
#else
-/* Break even between movem and move16 is at 38.7*2, but modulo 44. */
-#define MEMCPY_BLOCK_THRESHOLD (44*2)
+/* Break even between movem and move16 is really at 38.7 * 2, but
+ modulo 44, so up to the next multiple of 44, we use ordinary code. */
+#define MEMCPY_BY_BLOCK_THRESHOLD (44 * 2)
#endif
-void *memcpy(void *, const void *, unsigned int);
+/* No name ambiguities in this file. */
+__asm__ (".syntax no_register_prefix");
/* Experimentally off - libc_hidden_proto(memcpy) */
-void *memcpy(void *pdst,
- const void *psrc,
- unsigned int pn)
+void *
+memcpy(void *pdst, const void *psrc, size_t pn)
{
- /* Ok. Now we want the parameters put in special registers.
+ /* Now we want the parameters put in special registers.
Make sure the compiler is able to make something useful of this.
- As it is now: r10 -> r13; r11 -> r11 (nop); r12 -> r12 (nop).
+ As it is now: r10 -> r13; r11 -> r11 (nop); r12 -> r12 (nop).
If gcc was allright, it really would need no temporaries, and no
- stack space to save stuff on. */
+ stack space to save stuff on. */
-#ifndef MEMPCPY
register void *return_dst __asm__ ("r10") = pdst;
-#else
- /* FIXME: Use R10 for something. */
-# define return_dst dst
-#endif
-
- register char *dst __asm__ ("r13") = pdst;
- register char *src __asm__ ("r11") = (char *) psrc;
+ register unsigned char *dst __asm__ ("r13") = pdst;
+ register unsigned const char *src __asm__ ("r11") = psrc;
register int n __asm__ ("r12") = pn;
-
/* When src is aligned but not dst, this makes a few extra needless
cycles. I believe it would take as many to check that the
re-alignment was unnecessary. */
if (((unsigned long) dst & 3) != 0
/* Don't align if we wouldn't copy more than a few bytes; so we
- don't have to check further for overflows. */
+ don't have to check further for overflows. */
&& n >= 3)
{
if ((unsigned long) dst & 1)
- {
- n--;
- *(char*)dst = *(char*)src;
- src++;
- dst++;
- }
+ {
+ n--;
+ *dst = *src;
+ src++;
+ dst++;
+ }
if ((unsigned long) dst & 2)
- {
- n -= 2;
- *(short*)dst = *(short*)src;
- src += 2;
- dst += 2;
- }
+ {
+ n -= 2;
+ *(short *) dst = *(short *) src;
+ src += 2;
+ dst += 2;
+ }
}
- /* Decide which copying method to use. */
- if (n >= MEMCPY_BLOCK_THRESHOLD)
- {
- /* For large copies we use 'movem' */
+ /* Decide which copying method to use. */
+ if (n >= MEMCPY_BY_BLOCK_THRESHOLD)
+ {
+ /* It is not optimal to tell the compiler about clobbering any
+ registers; that will move the saving/restoring of those registers
+ to the function prologue/epilogue, and make non-movem sizes
+ suboptimal. */
+ __asm__ __volatile__
+ ("\
+ ;; GCC does promise correct register allocations, but let's \n\
+ ;; make sure it keeps its promises. \n\
+ .ifnc %0-%1-%2,$r13-$r11-$r12 \n\
+ .error \"GCC reg alloc bug: %0-%1-%4 != $r13-$r12-$r11\" \n\
+ .endif \n\
+ \n\
+ ;; Save the registers we'll use in the movem process \n\
+ ;; on the stack. \n\
+ subq 11*4,sp \n\
+ movem r10,[sp] \n\
+ \n\
+ ;; Now we've got this: \n\
+ ;; r11 - src \n\
+ ;; r13 - dst \n\
+ ;; r12 - n \n\
+ \n\
+ ;; Update n for the first loop. \n\
+ subq 44,r12 \n\
+0: \n\
+"
+#ifdef __arch_common_v10_v32
+ /* Cater to branch offset difference between v32 and v10. We
+ assume the branch below has an 8-bit offset. */
+" setf\n"
+#endif
+" movem [r11+],r10 \n\
+ subq 44,r12 \n\
+ bge 0b \n\
+ movem r10,[r13+] \n\
+ \n\
+ ;; Compensate for last loop underflowing n. \n\
+ addq 44,r12 \n\
+ \n\
+ ;; Restore registers from stack. \n\
+ movem [sp+],r10"
- /* It is not optimal to tell the compiler about clobbering any
- registers; that will move the saving/restoring of those registers
- to the function prologue/epilogue, and make non-movem sizes
- suboptimal.
+ /* Outputs. */
+ : "=r" (dst), "=r" (src), "=r" (n)
- This method is not foolproof; it assumes that the "register asm"
- declarations at the beginning of the function really are used
- here (beware: they may be moved to temporary registers).
- This way, we do not have to save/move the registers around into
- temporaries; we can safely use them straight away. */
- __asm__ __volatile__ ("\
- .syntax no_register_prefix \n\
- \n\
- ;; Check that the register asm declaration got right. \n\
- ;; The GCC manual explicitly says TRT will happen. \n\
- .ifnc %0-%1-%2,$r13-$r11-$r12 \n\
- .err \n\
- .endif \n\
- \n\
- ;; Save the registers we'll use in the movem process \n\
- ;; on the stack. \n\
- subq 11*4,sp \n\
- movem r10,[sp] \n\
- \n\
- ;; Now we've got this: \n\
- ;; r11 - src \n\
- ;; r13 - dst \n\
- ;; r12 - n \n\
- \n\
- ;; Update n for the first loop \n\
- subq 44,r12 \n\
-0: \n\
- movem [r11+],r10 \n\
- subq 44,r12 \n\
- bge 0b \n\
- movem r10,[r13+] \n\
- \n\
- addq 44,r12 ;; compensate for last loop underflowing n \n\
- \n\
- ;; Restore registers from stack \n\
- movem [sp+],r10"
+ /* Inputs. */
+ : "0" (dst), "1" (src), "2" (n));
+ }
- /* Outputs */ : "=r" (dst), "=r" (src), "=r" (n)
- /* Inputs */ : "0" (dst), "1" (src), "2" (n));
- }
+ while (n >= 16)
+ {
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
- /* Either we directly starts copying, using dword copying
- in a loop, or we copy as much as possible with 'movem'
- and then the last block (<44 bytes) is copied here.
- This will work since 'movem' will have updated src,dst,n. */
+ n -= 16;
+ }
- while ( n >= 16 )
- {
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- n -= 16;
- }
-
- /* A switch() is definitely the fastest although it takes a LOT of code.
- * Particularly if you inline code this.
- */
switch (n)
- {
+ {
case 0:
break;
+
case 1:
- *((char*)dst)++ = *((char*)src)++;
+ *dst = *src;
break;
+
case 2:
- *((short*)dst)++ = *((short*)src)++;
+ *(short *) dst = *(short *) src;
break;
+
case 3:
- *((short*)dst)++ = *((short*)src)++;
- *((char*)dst)++ = *((char*)src)++;
+ *(short *) dst = *(short *) src; dst += 2; src += 2;
+ *dst = *src;
break;
+
case 4:
- *((long*)dst)++ = *((long*)src)++;
+ *(long *) dst = *(long *) src;
break;
+
case 5:
- *((long*)dst)++ = *((long*)src)++;
- *((char*)dst)++ = *((char*)src)++;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *dst = *src;
break;
+
case 6:
- *((long*)dst)++ = *((long*)src)++;
- *((short*)dst)++ = *((short*)src)++;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(short *) dst = *(short *) src;
break;
+
case 7:
- *((long*)dst)++ = *((long*)src)++;
- *((short*)dst)++ = *((short*)src)++;
- *((char*)dst)++ = *((char*)src)++;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(short *) dst = *(short *) src; dst += 2; src += 2;
+ *dst = *src;
break;
+
case 8:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src;
break;
+
case 9:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((char*)dst)++ = *((char*)src)++;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *dst = *src;
break;
+
case 10:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((short*)dst)++ = *((short*)src)++;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(short *) dst = *(short *) src;
break;
+
case 11:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((short*)dst)++ = *((short*)src)++;
- *((char*)dst)++ = *((char*)src)++;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(short *) dst = *(short *) src; dst += 2; src += 2;
+ *dst = *src;
break;
+
case 12:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src;
break;
+
case 13:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((char*)dst)++ = *((char*)src)++;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *dst = *src;
break;
+
case 14:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((short*)dst)++ = *((short*)src)++;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(short *) dst = *(short *) src;
break;
+
case 15:
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((long*)dst)++ = *((long*)src)++;
- *((short*)dst)++ = *((short*)src)++;
- *((char*)dst)++ = *((char*)src)++;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(long *) dst = *(long *) src; dst += 4; src += 4;
+ *(short *) dst = *(short *) src; dst += 2; src += 2;
+ *dst = *src;
break;
- }
+ }
- return return_dst; /* destination pointer. */
-} /* memcpy() */
+ return return_dst;
+}
libc_hidden_def(memcpy)
Modified: trunk/uClibc/libc/string/cris/memset.c
===================================================================
--- trunk/uClibc/libc/string/cris/memset.c 2008-09-26 14:10:17 UTC (rev 23519)
+++ trunk/uClibc/libc/string/cris/memset.c 2008-09-26 14:37:08 UTC (rev 23520)
@@ -1,271 +1,263 @@
-/* Copyright (C) 2001, 2003 Free Software Foundation, Inc.
- Copyright (C) 1999, 2000 Axis Communications AB.
+/* A memset for CRIS.
+ Copyright (C) 1999-2008 Axis Communications.
+ All rights reserved.
- This file is part of the GNU C Library.
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
- The GNU C Library 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.
+ 1. Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
- 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
- Library General Public License for more details.
+ 2. Neither the name of Axis Communications nor the names of its
+ contributors may be used to endorse or promote products derived
+ from this software without specific prior written permission.
- You should have received a copy of the GNU Library General Public
- License along with the GNU C Library; see the file COPYING.LIB. If not,
- write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ THIS SOFTWARE IS PROVIDED BY AXIS COMMUNICATIONS AND ITS CONTRIBUTORS
+ ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL AXIS
+ COMMUNICATIONS OR ITS 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, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ POSSIBILITY OF SUCH DAMAGE. */
-/*#************************************************************************#*/
-/*#-------------------------------------------------------------------------*/
-/*# */
-/*# FUNCTION NAME: memset() */
-/*# */
-/*# PARAMETERS: void* dst; Destination address. */
-/*# int c; Value of byte to write. */
-/*# int len; Number of bytes to write. */
-/*# */
-/*# RETURNS: dst. */
-/*# */
-/*# DESCRIPTION: Sets the memory dst of length len bytes to c, as standard. */
-/*# Framework taken from memcpy. This routine is */
-/*# very sensitive to compiler changes in register allocation. */
-/*# Should really be rewritten to avoid this problem. */
-/*# */
-/*#-------------------------------------------------------------------------*/
-/*# */
-/*# HISTORY */
-/*# */
-/*# DATE NAME CHANGES */
-/*# ---- ---- ------- */
-/*# 990713 HP Tired of watching this function (or */
-/*# really, the nonoptimized generic */
-/*# implementation) take up 90% of simulator */
-/*# output. Measurements needed. */
-/*# */
-/*#-------------------------------------------------------------------------*/
+/* FIXME: This file should really only be used for reference, as the
+ result is somewhat depending on gcc generating what we expect rather
+ than what we describe. An assembly file should be used instead. */
-/* No, there's no macro saying 12*4, since it is "hard" to get it into
- the asm in a good way. Thus better to expose the problem everywhere.
- */
+#include <string.h>
-/* Assuming 1 cycle per dword written or read (ok, not really true), and
- one per instruction, then 43+3*(n/48-1) <= 24+24*(n/48-1)
- so n >= 45.7; n >= 0.9; we win on the first full 48-byte block to set. */
+/* Note the multiple occurrence of the expression "12*4", including the
+ asm. It is hard to get it into the asm in a good way. Thus better to
+ expose the problem everywhere: no macro. */
-#define ZERO_BLOCK_SIZE (1*12*4)
+/* Assuming one cycle per dword written or read (ok, not really true; the
+ world is not ideal), and one cycle per instruction, then 43+3*(n/48-1)
+ <= 24+24*(n/48-1) so n >= 45.7; n >= 0.9; we win on the first full
+ 48-byte block to set. */
-void *memset(void *, int, unsigned long);
+#define MEMSET_BY_BLOCK_THRESHOLD (1 * 48)
+/* No name ambiguities in this file. */
+__asm__ (".syntax no_register_prefix");
+
/* Experimentally off - libc_hidden_proto(memset) */
-void *memset(void *pdst,
- int c,
- unsigned long plen)
+void *memset(void *pdst, int c, unsigned int plen)
{
- /* Ok. Now we want the parameters put in special registers.
- Make sure the compiler is able to make something useful of this. */
+ /* Now we want the parameters in special registers. Make sure the
+ compiler does something usable with this. */
register char *return_dst __asm__ ("r10") = pdst;
- register long n __asm__ ("r12") = plen;
+ register int n __asm__ ("r12") = plen;
register int lc __asm__ ("r11") = c;
- /* Most apps use memset sanely. Only those memsetting about 3..4
- bytes or less get penalized compared to the generic implementation
- - and that's not really sane use. */
+ /* Most apps use memset sanely. Memsetting about 3..4 bytes or less get
+ penalized here compared to the generic implementation. */
- /* Ugh. This is fragile at best. Check with newer GCC releases, if
- they compile cascaded "x |= x << 8" sanely! */
- __asm__("movu.b %0,$r13 \n\
- lslq 8,$r13 \n\
- move.b %0,$r13 \n\
- move.d $r13,%0 \n\
- lslq 16,$r13 \n\
- or.d $r13,%0"
- : "=r" (lc) : "0" (lc) : "r13");
+ /* This is fragile performancewise at best. Check with newer GCC
+ releases, if they compile cascaded "x |= x << 8" to sane code. */
+ __asm__("movu.b %0,r13 \n\
+ lslq 8,r13 \n\
+ move.b %0,r13 \n\
+ move.d r13,%0 \n\
+ lslq 16,r13 \n\
+ or.d r13,%0"
+ : "=r" (lc) /* Inputs. */
+ : "0" (lc) /* Outputs. */
+ : "r13"); /* Trash. */
{
register char *dst __asm__ ("r13") = pdst;
- if (((unsigned long) pdst & 3) != 0
- /* Oops! n=0 must be a legal call, regardless of alignment. */
- && n >= 3)
- {
- if ((unsigned long)dst & 1)
- {
- *dst = (char) lc;
- n--;
- dst++;
- }
+ if (((unsigned long) pdst & 3) != 0
+ /* Oops! n = 0 must be a valid call, regardless of alignment. */
+ && n >= 3)
+ {
+ if ((unsigned long) dst & 1)
+ {
+ *dst = (char) lc;
+ n--;
+ dst++;
+ }
- if ((unsigned long)dst & 2)
- {
- *(short *)dst = lc;
- n -= 2;
- dst += 2;
- }
- }
+ if ((unsigned long) dst & 2)
+ {
+ *(short *) dst = lc;
+ n -= 2;
+ dst += 2;
+ }
+ }
- /* Now the fun part. For the threshold value of this, check the equation
- above. */
- /* Decide which copying method to use. */
- if (n >= ZERO_BLOCK_SIZE)
- {
- /* For large copies we use 'movem' */
+ /* Decide which setting method to use. */
+ if (n >= MEMSET_BY_BLOCK_THRESHOLD)
+ {
+ /* It is not optimal to tell the compiler about clobbering any
+ registers; that will move the saving/restoring of those registers
+ to the function prologue/epilogue, and make non-block sizes
+ suboptimal. */
+ __asm__ __volatile__
+ ("\
+ ;; GCC does promise correct register allocations, but let's \n\
+ ;; make sure it keeps its promises. \n\
+ .ifnc %0-%1-%4,$r13-$r12-$r11 \n\
+ .error \"GCC reg alloc bug: %0-%1-%4 != $r13-$r12-$r11\" \n\
+ .endif \n\
+ \n\
+ ;; Save the registers we'll clobber in the movem process \n\
+ ;; on the stack. Don't mention them to gcc, it will only be \n\
+ ;; upset. \n\
+ subq 11*4,sp \n\
+ movem r10,[sp] \n\
+ \n\
+ move.d r11,r0 \n\
+ move.d r11,r1 \n\
+ move.d r11,r2 \n\
+ move.d r11,r3 \n\
+ move.d r11,r4 \n\
+ move.d r11,r5 \n\
+ move.d r11,r6 \n\
+ move.d r11,r7 \n\
+ move.d r11,r8 \n\
+ move.d r11,r9 \n\
+ move.d r11,r10 \n\
+ \n\
+ ;; Now we've got this: \n\
+ ;; r13 - dst \n\
+ ;; r12 - n \n\
+ \n\
+ ;; Update n for the first loop \n\
+ subq 12*4,r12 \n\
+0: \n\
+"
+#ifdef __arch_common_v10_v32
+ /* Cater to branch offset difference between v32 and v10. We
+ assume the branch below has an 8-bit offset. */
+" setf\n"
+#endif
+" subq 12*4,r12 \n\
+ bge 0b \n\
+ movem r11,[r13+] \n\
+ \n\
+ ;; Compensate for last loop underflowing n. \n\
+ addq 12*4,r12 \n\
+ \n\
+ ;; Restore registers from stack. \n\
+ movem [sp+],r10"
- /* It is not optimal to tell the compiler about clobbering any
- registers; that will move the saving/restoring of those registers
- to the function prologue/epilogue, and make non-movem sizes
- suboptimal.
+ /* Outputs. */
+ : "=r" (dst), "=r" (n)
- This method is not foolproof; it assumes that the "asm reg"
- declarations at the beginning of the function really are used
- here (beware: they may be moved to temporary registers).
- This way, we do not have to save/move the registers around into
- temporaries; we can safely use them straight away. */
- __asm__ __volatile__ (" \n\
- .syntax no_register_prefix \n\
- \n\
- ;; Check that the register asm declaration got right. \n\
- ;; The GCC manual explicitly says there's no warranty for that (too). \n\
- .ifnc %0-%1-%4,$r13-$r12-$r11 \n\
- .err \n\
- .endif \n\
- \n\
- ;; Save the registers we'll clobber in the movem process \n\
- ;; on the stack. Don't mention them to gcc, it will only be \n\
- ;; upset. \n\
- subq 11*4,sp \n\
- movem r10,[sp] \n\
- \n\
- move.d r11,r0 \n\
- move.d r11,r1 \n\
- move.d r11,r2 \n\
- move.d r11,r3 \n\
- move.d r11,r4 \n\
- move.d r11,r5 \n\
- move.d r11,r6 \n\
- move.d r11,r7 \n\
- move.d r11,r8 \n\
- move.d r11,r9 \n\
- move.d r11,r10 \n\
- \n\
- ;; Now we've got this: \n\
- ;; r13 - dst \n\
- ;; r12 - n \n\
- \n\
- ;; Update n for the first loop \n\
- subq 12*4,r12 \n\
-0: \n\
- subq 12*4,r12 \n\
- bge 0b \n\
- movem r11,[r13+] \n\
- \n\
- addq 12*4,r12 ;; compensate for last loop underflowing n \n\
- \n\
- ;; Restore registers from stack \n\
- movem [sp+],r10"
+ /* Inputs. */
+ : "0" (dst), "1" (n), "r" (lc));
+ }
- /* Outputs */ : "=r" (dst), "=r" (n)
- /* Inputs */ : "0" (dst), "1" (n), "r" (lc));
+ /* An ad-hoc unroll, used for 4*12-1..16 bytes. */
+ while (n >= 16)
+ {
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ n -= 16;
+ }
- }
-
- /* Either we directly starts copying, using dword copying
- in a loop, or we copy as much as possible with 'movem'
- and then the last block (<44 bytes) is copied here.
- This will work since 'movem' will have updated src,dst,n. */
-
- while ( n >= 16 )
- {
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- n -= 16;
- }
-
- /* A switch() is definitely the fastest although it takes a LOT of code.
- * Particularly if you inline code this.
- */
switch (n)
- {
+ {
case 0:
break;
+
case 1:
- *(char*)dst = (char) lc;
+ *dst = (char) lc;
break;
+
case 2:
- *(short*)dst = (short) lc;
+ *(short *) dst = (short) lc;
break;
+
case 3:
- *((short*)dst)++ = (short) lc;
- *(char*)dst = (char) lc;
+ *(short *) dst = (short) lc; dst += 2;
+ *dst = (char) lc;
break;
+
case 4:
- *((long*)dst)++ = lc;
+ *(long *) dst = lc;
break;
+
case 5:
- *((long*)dst)++ = lc;
- *(char*)dst = (char) lc;
+ *(long *) dst = lc; dst += 4;
+ *dst = (char) lc;
break;
+
case 6:
- *((long*)dst)++ = lc;
- *(short*)dst = (short) lc;
+ *(long *) dst = lc; dst += 4;
+ *(short *) dst = (short) lc;
break;
+
case 7:
- *((long*)dst)++ = lc;
- *((short*)dst)++ = (short) lc;
- *(char*)dst = (char) lc;
+ *(long *) dst = lc; dst += 4;
+ *(short *) dst = (short) lc; dst += 2;
+ *dst = (char) lc;
break;
+
case 8:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc;
break;
+
case 9:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *(char*)dst = (char) lc;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *dst = (char) lc;
break;
+
case 10:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *(short*)dst = (short) lc;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *(short *) dst = (short) lc;
break;
+
case 11:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((short*)dst)++ = (short) lc;
- *(char*)dst = (char) lc;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *(short *) dst = (short) lc; dst += 2;
+ *dst = (char) lc;
break;
+
case 12:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc;
break;
+
case 13:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *(char*)dst = (char) lc;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *dst = (char) lc;
break;
+
case 14:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *(short*)dst = (short) lc;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *(short *) dst = (short) lc;
break;
+
case 15:
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((long*)dst)++ = lc;
- *((short*)dst)++ = (short) lc;
- *(char*)dst = (char) lc;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *(long *) dst = lc; dst += 4;
+ *(short *) dst = (short) lc; dst += 2;
+ *dst = (char) lc;
break;
- }
+ }
}
- return return_dst; /* destination pointer. */
-} /* memset() */
+ return return_dst;
+}
libc_hidden_def(memset)
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