gcc/libgcc/sync.c
2024-01-03 12:19:35 +01:00

176 lines
5.7 KiB
C

/* Out-of-line libgcc versions of __sync_* builtins. */
/* Copyright (C) 2008-2024 Free Software Foundation, Inc.
This file is part of GCC.
GCC 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, or (at your option) any later
version.
GCC 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.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* This file is used by targets whose makefiles define SYNC
to "yes". It is compiled with SYNC_CFLAGS and provides
out-of-line versions of all relevant __sync_* primitives.
These routines are intended for targets like MIPS that have two
ISA encodings (the "normal" ISA and the MIPS16 ISA). The normal
ISA provides full synchronization capabilities but the MIPS16 ISA
has no encoding for them. MIPS16 code must therefore call external
non-MIPS16 implementations of the __sync_* routines.
The file is compiled once for each routine. The following __foo
routines are selected by defining a macro called L<foo>:
__sync_synchronize
The following __foo_N routines are selected by defining FN=foo
and SIZE=N:
__sync_fetch_and_add_N
__sync_fetch_and_sub_N
__sync_fetch_and_or_N
__sync_fetch_and_and_N
__sync_fetch_and_xor_N
__sync_fetch_and_nand_N
__sync_add_and_fetch_N
__sync_sub_and_fetch_N
__sync_or_and_fetch_N
__sync_and_and_fetch_N
__sync_xor_and_fetch_N
__sync_nand_and_fetch_N
__sync_bool_compare_and_swap_N
__sync_val_compare_and_swap_N
__sync_lock_test_and_set_N
SIZE can be 1, 2, 4, 8 or 16. __foo_N is omitted if the target does
not provide __sync_compare_and_swap_N.
Note that __sync_lock_release does not fall back on external
__sync_lock_release_N functions. The default implementation
of __sync_lock_release is a call to __sync_synchronize followed
by a store of zero, so we don't need separate library functions
for it. */
#if defined FN
/* Define functions called __sync_<NAME>_<UNITS>, with one macro per
signature. TYPE is a type that has UNITS bytes. */
#define DEFINE_V_PV(NAME, UNITS, TYPE) \
TYPE \
__##NAME##_##UNITS (TYPE *ptr, TYPE value) \
{ \
return __##NAME (ptr, value); \
}
#define DEFINE_V_PVV(NAME, UNITS, TYPE) \
TYPE \
__##NAME##_##UNITS (TYPE *ptr, TYPE value1, TYPE value2) \
{ \
return __##NAME (ptr, value1, value2); \
}
#define DEFINE_BOOL_PVV(NAME, UNITS, TYPE) \
_Bool \
__##NAME##_##UNITS (TYPE *ptr, TYPE value1, TYPE value2) \
{ \
return __##NAME (ptr, value1, value2); \
}
/* Map function names to the appropriate DEFINE_* macro. */
#define local_sync_fetch_and_add DEFINE_V_PV
#define local_sync_fetch_and_sub DEFINE_V_PV
#define local_sync_fetch_and_or DEFINE_V_PV
#define local_sync_fetch_and_and DEFINE_V_PV
#define local_sync_fetch_and_xor DEFINE_V_PV
#define local_sync_fetch_and_nand DEFINE_V_PV
#define local_sync_add_and_fetch DEFINE_V_PV
#define local_sync_sub_and_fetch DEFINE_V_PV
#define local_sync_or_and_fetch DEFINE_V_PV
#define local_sync_and_and_fetch DEFINE_V_PV
#define local_sync_xor_and_fetch DEFINE_V_PV
#define local_sync_nand_and_fetch DEFINE_V_PV
#define local_sync_bool_compare_and_swap DEFINE_BOOL_PVV
#define local_sync_val_compare_and_swap DEFINE_V_PVV
#define local_sync_lock_test_and_set DEFINE_V_PV
/* Define the function __<NAME>_<UNITS>, given that TYPE is a type with
UNITS bytes. */
#define DEFINE1(NAME, UNITS, TYPE) \
static int unused[sizeof (TYPE) == UNITS ? 1 : -1] \
__attribute__((unused)); \
local_##NAME (NAME, UNITS, TYPE);
/* As above, but performing macro expansion on the arguments. */
#define DEFINE(NAME, UNITS, TYPE) DEFINE1 (NAME, UNITS, TYPE)
/* Find an appropriate type TYPE for SIZE and invoke DEFINE (FN, SIZE, TYPE).
The types chosen here may be incorrect for some targets.
For example, targets with 16-byte atomicity support might not
support OImode. We would need some kind of target-specific
override if that becomes a problem. */
#if SIZE == 1 && __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1
typedef unsigned int UQItype __attribute__((mode (QI)));
DEFINE (FN, 1, UQItype)
#elif SIZE == 2 && __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2
typedef unsigned int UHItype __attribute__((mode (HI)));
DEFINE (FN, 2, UHItype)
#elif SIZE == 4 && __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4
typedef unsigned int USItype __attribute__((mode (SI)));
DEFINE (FN, 4, USItype)
#elif SIZE == 8 && __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8
typedef unsigned int UDItype __attribute__((mode (DI)));
DEFINE (FN, 8, UDItype)
#elif SIZE == 16 && __GCC_HAVE_SYNC_COMPARE_AND_SWAP_16
typedef unsigned int UOItype __attribute__((mode (OI)));
DEFINE (FN, 8, UOItype)
#endif
#elif __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1 \
|| __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 \
|| __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 \
|| __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 \
|| __GCC_HAVE_SYNC_COMPARE_AND_SWAP_16
#if defined Lsync_synchronize
void
__sync_synchronize (void)
{
__sync_synchronize ();
}
#endif
#endif