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/* IBM_PROLOG_BEGIN_TAG */
/* This is an automatically generated prolog. */
/* */
/* $Source: src/lib/string_utils.C $ */
/* */
/* OpenPOWER HostBoot Project */
/* */
/* Contributors Listed Below - COPYRIGHT 2016,2017 */
/* [+] International Business Machines Corp. */
/* */
/* */
/* Licensed under the Apache License, Version 2.0 (the "License"); */
/* you may not use this file except in compliance with the License. */
/* You may obtain a copy of the License at */
/* */
/* http://www.apache.org/licenses/LICENSE-2.0 */
/* */
/* Unless required by applicable law or agreed to in writing, software */
/* distributed under the License is distributed on an "AS IS" BASIS, */
/* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or */
/* implied. See the License for the specific language governing */
/* permissions and limitations under the License. */
/* */
/* IBM_PROLOG_END_TAG */
#include <string.h>
#include <stdlib.h>
extern "C" void *memset(void *vdest, int ch, size_t len)
{
// TODO: align to an 8-byte boundary
// Loop, storing 8 bytes every 3 instructions
long *ldest = reinterpret_cast<long *>(vdest);
if (len >= sizeof(long))
{
long lch = ch & 0xFF;
lch |= lch<<8;
lch |= lch<<16;
lch |= lch<<32;
size_t len8 = len / sizeof(long);
size_t i = len8;
do {
ldest[--i] = lch;
} while( i > 0 );
ldest += len8;
len -= len8 * sizeof(long);
}
// Loop, storing 1 byte every 3 instructions
char *cdest = reinterpret_cast<char *>(ldest);
while (len >= sizeof(char))
{
*cdest++ = ch;
len -= sizeof(char);
}
return vdest;
}
extern "C" void *memcpy(void *vdest, const void *vsrc, size_t len)
{
// TODO: align to an 8-byte boundary?
// Loop, copying 8 bytes every 5 instructions (TODO: 8/4 should be possible)
long *ldest = reinterpret_cast<long *>(vdest);
const long *lsrc = reinterpret_cast<const long *>(vsrc);
while (len >= sizeof(long))
{
*ldest++ = *lsrc++;
len -= sizeof(long);
}
// Loop, copying 1 byte every 4 instructions
char *cdest = reinterpret_cast<char *>(ldest);
const char *csrc = reinterpret_cast<const char *>(lsrc);
for (size_t i = 0; i < len; ++i)
{
cdest[i] = csrc[i];
}
return vdest;
}
extern "C" void *memmove(void *vdest, const void *vsrc, size_t len)
{
// Copy first-to-last
if (vdest <= vsrc)
{
return memcpy(vdest,vsrc,len);
}
// Copy last-to-first (TO_DO: optimize)
char *dest = reinterpret_cast<char *>(vdest);
const char *src = reinterpret_cast<const char *>(vsrc);
for (size_t i = len; i > 0;)
{
--i;
dest[i] = src[i];
}
return vdest;
}
extern "C" int memcmp(const void *p1, const void *p2, size_t len)
{
const char *c1 = reinterpret_cast<const char *>(p1);
const char *c2 = reinterpret_cast<const char *>(p2);
for (size_t i = 0; i < len; ++i)
{
long n = static_cast<long>(c1[i]) - static_cast<long>(c2[i]);
if (n != 0)
{
return n;
}
}
return 0;
}
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