grub/grub-core/kern/compiler-rt.c
Vladimir Serbinenko 064360e667 Remove libgcc dependency.
libgcc for boot environment isn't always present and compatible.
libgcc is often absent if endianness or bit-size at boot is different
from running OS.
libgcc may use optimised opcodes that aren't available on boot time.
So instead of relying on libgcc shipped with the compiler, supply
the functions in GRUB directly.
Tests are present to ensure that those replacement functions behave the
way compiler expects them to.
2015-03-03 20:50:37 +01:00

404 lines
7.4 KiB
C

/* compiler-rt.c - compiler helpers. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 1999,2000,2001,2002,2003,2004,2005,2006,2007,2008,2009,2010-2014 Free Software Foundation, Inc.
*
* GRUB 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, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/misc.h>
#include <grub/compiler-rt.h>
#ifndef GRUB_EMBED_DECOMPRESSOR
void * GRUB_BUILTIN_ATTR
memcpy (void *dest, const void *src, grub_size_t n)
{
return grub_memmove (dest, src, n);
}
void * GRUB_BUILTIN_ATTR
memmove (void *dest, const void *src, grub_size_t n)
{
return grub_memmove (dest, src, n);
}
int GRUB_BUILTIN_ATTR
memcmp (const void *s1, const void *s2, grub_size_t n)
{
return grub_memcmp (s1, s2, n);
}
void * GRUB_BUILTIN_ATTR
memset (void *s, int c, grub_size_t n)
{
return grub_memset (s, c, n);
}
#ifdef __APPLE__
void GRUB_BUILTIN_ATTR
__bzero (void *s, grub_size_t n)
{
grub_memset (s, 0, n);
}
#endif
#if GRUB_DIVISION_IN_SOFTWARE
grub_uint32_t
__udivsi3 (grub_uint32_t a, grub_uint32_t b)
{
return grub_divmod64 (a, b, 0);
}
grub_int32_t
__divsi3 (grub_int32_t a, grub_int32_t b)
{
return grub_divmod64s (a, b, 0);
}
grub_uint32_t
__umodsi3 (grub_uint32_t a, grub_uint32_t b)
{
grub_uint64_t ret;
grub_divmod64 (a, b, &ret);
return ret;
}
grub_int32_t
__modsi3 (grub_int32_t a, grub_int32_t b)
{
grub_int64_t ret;
grub_divmod64s (a, b, &ret);
return ret;
}
grub_uint64_t
__udivdi3 (grub_uint64_t a, grub_uint64_t b)
{
return grub_divmod64 (a, b, 0);
}
grub_uint64_t
__umoddi3 (grub_uint64_t a, grub_uint64_t b)
{
grub_uint64_t ret;
grub_divmod64 (a, b, &ret);
return ret;
}
grub_int64_t
__divdi3 (grub_int64_t a, grub_int64_t b)
{
return grub_divmod64s (a, b, 0);
}
grub_int64_t
__moddi3 (grub_int64_t a, grub_int64_t b)
{
grub_int64_t ret;
grub_divmod64s (a, b, &ret);
return ret;
}
#endif
#endif
#ifdef NEED_CTZDI2
unsigned
__ctzdi2 (grub_uint64_t x)
{
unsigned ret = 0;
if (!x)
return 64;
if (!(x & 0xffffffff))
{
x >>= 32;
ret |= 32;
}
if (!(x & 0xffff))
{
x >>= 16;
ret |= 16;
}
if (!(x & 0xff))
{
x >>= 8;
ret |= 8;
}
if (!(x & 0xf))
{
x >>= 4;
ret |= 4;
}
if (!(x & 0x3))
{
x >>= 2;
ret |= 2;
}
if (!(x & 0x1))
{
x >>= 1;
ret |= 1;
}
return ret;
}
#endif
#ifdef NEED_CTZSI2
unsigned
__ctzsi2 (grub_uint32_t x)
{
unsigned ret = 0;
if (!x)
return 32;
if (!(x & 0xffff))
{
x >>= 16;
ret |= 16;
}
if (!(x & 0xff))
{
x >>= 8;
ret |= 8;
}
if (!(x & 0xf))
{
x >>= 4;
ret |= 4;
}
if (!(x & 0x3))
{
x >>= 2;
ret |= 2;
}
if (!(x & 0x1))
{
x >>= 1;
ret |= 1;
}
return ret;
}
#endif
#if defined (__clang__) && !defined(GRUB_EMBED_DECOMPRESSOR)
/* clang emits references to abort(). */
void __attribute__ ((noreturn))
abort (void)
{
grub_fatal ("compiler abort");
}
#endif
#if (defined (__MINGW32__) || defined (__CYGWIN__))
void __register_frame_info (void)
{
}
void __deregister_frame_info (void)
{
}
void ___chkstk_ms (void)
{
}
void __chkstk_ms (void)
{
}
#endif
union component64
{
grub_uint64_t full;
struct
{
#ifdef GRUB_CPU_WORDS_BIGENDIAN
grub_uint32_t high;
grub_uint32_t low;
#else
grub_uint32_t low;
grub_uint32_t high;
#endif
};
};
#if defined (__powerpc__) || defined (__arm__) || defined(__mips__)
/* Based on libgcc2.c from gcc suite. */
grub_uint64_t
__lshrdi3 (grub_uint64_t u, int b)
{
if (b == 0)
return u;
const union component64 uu = {.full = u};
const int bm = 32 - b;
union component64 w;
if (bm <= 0)
{
w.high = 0;
w.low = (grub_uint32_t) uu.high >> -bm;
}
else
{
const grub_uint32_t carries = (grub_uint32_t) uu.high << bm;
w.high = (grub_uint32_t) uu.high >> b;
w.low = ((grub_uint32_t) uu.low >> b) | carries;
}
return w.full;
}
/* Based on libgcc2.c from gcc suite. */
grub_uint64_t
__ashrdi3 (grub_uint64_t u, int b)
{
if (b == 0)
return u;
const union component64 uu = {.full = u};
const int bm = 32 - b;
union component64 w;
if (bm <= 0)
{
/* w.high = 1..1 or 0..0 */
w.high = ((grub_int32_t) uu.high) >> (32 - 1);
w.low = ((grub_int32_t) uu.high) >> -bm;
}
else
{
const grub_uint32_t carries = ((grub_uint32_t) uu.high) << bm;
w.high = ((grub_int32_t) uu.high) >> b;
w.low = ((grub_uint32_t) uu.low >> b) | carries;
}
return w.full;
}
/* Based on libgcc2.c from gcc suite. */
grub_uint64_t
__ashldi3 (grub_uint64_t u, int b)
{
if (b == 0)
return u;
const union component64 uu = {.full = u};
const int bm = 32 - b;
union component64 w;
if (bm <= 0)
{
w.low = 0;
w.high = (grub_uint32_t) uu.low << -bm;
}
else
{
const grub_uint32_t carries = (grub_uint32_t) uu.low >> bm;
w.low = (grub_uint32_t) uu.low << b;
w.high = ((grub_uint32_t) uu.high << b) | carries;
}
return w.full;
}
/* Based on libgcc2.c from gcc suite. */
int
__ucmpdi2 (grub_uint64_t a, grub_uint64_t b)
{
union component64 ac, bc;
ac.full = a;
bc.full = b;
if (ac.high < bc.high)
return 0;
else if (ac.high > bc.high)
return 2;
if (ac.low < bc.low)
return 0;
else if (ac.low > bc.low)
return 2;
return 1;
}
#endif
#if defined (__powerpc__) || defined(__mips__) || defined(__sparc__) || defined(__arm__)
/* Based on libgcc2.c from gcc suite. */
grub_uint32_t
__bswapsi2 (grub_uint32_t u)
{
return ((((u) & 0xff000000) >> 24)
| (((u) & 0x00ff0000) >> 8)
| (((u) & 0x0000ff00) << 8)
| (((u) & 0x000000ff) << 24));
}
/* Based on libgcc2.c from gcc suite. */
grub_uint64_t
__bswapdi2 (grub_uint64_t u)
{
return ((((u) & 0xff00000000000000ull) >> 56)
| (((u) & 0x00ff000000000000ull) >> 40)
| (((u) & 0x0000ff0000000000ull) >> 24)
| (((u) & 0x000000ff00000000ull) >> 8)
| (((u) & 0x00000000ff000000ull) << 8)
| (((u) & 0x0000000000ff0000ull) << 24)
| (((u) & 0x000000000000ff00ull) << 40)
| (((u) & 0x00000000000000ffull) << 56));
}
#endif
#ifdef __arm__
grub_uint32_t
__aeabi_uidiv (grub_uint32_t a, grub_uint32_t b)
__attribute__ ((alias ("__udivsi3")));
grub_int32_t
__aeabi_idiv (grub_int32_t a, grub_int32_t b)
__attribute__ ((alias ("__divsi3")));
void *__aeabi_memcpy (void *dest, const void *src, grub_size_t n)
__attribute__ ((alias ("grub_memcpy")));
void *__aeabi_memset (void *s, int c, grub_size_t n)
__attribute__ ((alias ("memset")));
int
__aeabi_ulcmp (grub_uint64_t a, grub_uint64_t b)
{
return __ucmpdi2 (a, b) - 1;
}
grub_uint64_t
__aeabi_lasr (grub_uint64_t u, int b)
__attribute__ ((alias ("__ashrdi3")));
grub_uint64_t
__aeabi_llsr (grub_uint64_t u, int b)
__attribute__ ((alias ("__lshrdi3")));
grub_uint64_t
__aeabi_llsl (grub_uint64_t u, int b)
__attribute__ ((alias ("__ashldi3")));
#endif