Hello,
it seems that the variants without a _1, _2, ... are explicitly provided
(libatomic_i.h):
/* And the generic sized versions. */
void libat_load (size_t, void *, void *, int) MAN(load);
void libat_store (size_t, void *, void *, int) MAN(store);
void libat_exchange (size_t, void *, void *, void *, int) MAN(exchange);
bool libat_compare_exchange (size_t, void *, void *, void *, int, int)
MAN(compare_exchange);
bool libat_is_lock_free (size_t, void *) MAN(is_lock_free);
I am not really sure why there is no alias to the _1 variant for the
DECLARE_ALL_SIZED(1);
operations. Does this patch make any sense?
diff --git a/libatomic/libatomic_i.h b/libatomic/libatomic_i.h
index e59dd412e17..afc356d257d 100644
--- a/libatomic/libatomic_i.h
+++ b/libatomic/libatomic_i.h
@@ -237,7 +237,8 @@ bool libat_is_lock_free (size_t, void *) MAN(is_lock_free);
#endif
#if IFUNC_ALT
-# define EXPORT_ALIAS(X) /* exported symbol in non-alternate file */
+# define EXPORT_ALIAS_2(X, Y) /* exported symbol in non-alternate file */
+# define EXPORT_ALIAS(X)
#elif defined(N) && IFUNC_NCOND(N)
# if IFUNC_NCOND(N) == 1
# define GEN_SELECTOR(X) \
@@ -278,18 +279,21 @@ bool libat_is_lock_free (size_t, void *)
MAN(is_lock_free);
# else
# error "Unsupported number of ifunc alternatives."
# endif
-# define EXPORT_ALIAS(X) \
+# define EXPORT_ALIAS_2(X, Y) \
GEN_SELECTOR(X) \
- typeof(C2(libat_,X)) C2(ifunc_,X) \
- ASMNAME(C2(__atomic_,X)) \
+ typeof(C2(libat_,X)) C2(ifunc_,Y) \
+ ASMNAME(C2(__atomic_,Y)) \
__attribute__((ifunc(S(C2(select_,X)))))
+# define EXPORT_ALIAS(X) EXPORT_ALIAS_2(X, X)
#elif defined(HAVE_ATTRIBUTE_ALIAS)
-# define EXPORT_ALIAS(X) \
- extern typeof(C2(libat_,X)) C2(export_,X) \
- ASMNAME(C2(__atomic_,X)) \
+# define EXPORT_ALIAS_2(X, Y) \
+ extern typeof(C2(libat_,X)) C2(export_,Y) \
+ ASMNAME(C2(__atomic_,Y)) \
__attribute__((alias(S(C2(libat_,X)))))
+# define EXPORT_ALIAS(X) EXPORT_ALIAS_2(X, X)
#else
-# define EXPORT_ALIAS(X) /* original symbol is exported */
+# define EXPORT_ALIAS_2(X, Y) /* original symbol is exported */
+# define EXPORT_ALIAS(X)
#endif
#endif /* LIBATOMIC_H */
diff --git a/libatomic/tas_n.c b/libatomic/tas_n.c
index 036a3d23307..fad9d00b280 100644
--- a/libatomic/tas_n.c
+++ b/libatomic/tas_n.c
@@ -114,4 +114,7 @@ SIZE(libat_test_and_set) (UTYPE *mptr, int smodel UNUSED)
#endif
EXPORT_ALIAS (SIZE(test_and_set));
+#if N == 1
+EXPORT_ALIAS_2 (SIZE(test_and_set), test_and_set);
+#endif
#undef LAT_TAS_N
----- Am 2. Jul 2025 um 9:20 schrieb Sebastian Huber
sebastian.hu...@embedded-brains.de:
> Hello,
>
> for the RISC-V target, I would like to use the -march=rv64imc ISA variant.
> However, there is an issue with the libatomic for this target in the RTEMS
> configuration. For this test code:
>
> #include <stdatomic.h>
>
> bool tas(atomic_flag *f)
> {
> return atomic_flag_test_and_set(f);
> }
>
> GCC 15 generates:
>
> riscv-rtems6-gcc -O2 -S -o - -march=rv64imc -mabi=lp64 test.c
> .file "test.c"
> .option nopic
> .attribute arch, "rv64i2p1_m2p0_c2p0_zmmul1p0_zca1p0"
> .attribute unaligned_access, 0
> .attribute stack_align, 16
> .text
> .align 1
> .globl tas
> .type tas, @function
> tas:
> li a1,5
> tail __atomic_test_and_set
> .size tas, .-tas
> .ident "GCC: 15.1.1 20250517"
> .section .note.GNU-stack,"",@progbits
>
> In the corresponding libatomic.a multilib, there are the following functions
> (omitting *_4, *_8, *_16 variants which exist for all *_1 variants):
>
> __atomic_add_fetch_1
> __atomic_and_fetch_1
> __atomic_compare_exchange
> __atomic_compare_exchange_1
> __atomic_exchange
> __atomic_exchange_1
> __atomic_feraiseexcept
> __atomic_fetch_add_1
> __atomic_fetch_and_1
> __atomic_fetch_nand_1
> __atomic_fetch_or_1
> __atomic_fetch_sub_1
> __atomic_fetch_xor_1
> __atomic_is_lock_free
> __atomic_load
> __atomic_load_1
> __atomic_nand_fetch_1
> __atomic_or_fetch_1
> __atomic_store
> __atomic_store_1
> __atomic_sub_fetch_1
> __atomic_test_and_set_1
> __atomic_xor_fetch_1
>
> Some operations have a variant without a _1, _2, _4, _8, and _16 postfix
> (example: __atomic_store). Others do not have such a variant, examples:
> __atomic_test_and_set_1, __atomic_add_fetch_1.
>
> I am a bit clueless what is going on here. Are the missing variants a
> libatomic
> configuration error? Is it a general configuration error or specific to RTEMS?
>
> --
> embedded brains GmbH & Co. KG
> Herr Sebastian HUBER
> Dornierstr. 4
> 82178 Puchheim
> Germany
> email: sebastian.hu...@embedded-brains.de
> phone: +49-89-18 94 741 - 16
> fax: +49-89-18 94 741 - 08
>
> Registergericht: Amtsgericht München
> Registernummer: HRB 157899
> Vertretungsberechtigte Geschäftsführer: Peter Rasmussen, Thomas Dörfler
> Unsere Datenschutzerklärung finden Sie hier:
> https://embedded-brains.de/datenschutzerklaerung/
--
embedded brains GmbH & Co. KG
Herr Sebastian HUBER
Dornierstr. 4
82178 Puchheim
Germany
email: sebastian.hu...@embedded-brains.de
phone: +49-89-18 94 741 - 16
fax: +49-89-18 94 741 - 08
Registergericht: Amtsgericht München
Registernummer: HRB 157899
Vertretungsberechtigte Geschäftsführer: Peter Rasmussen, Thomas Dörfler
Unsere Datenschutzerklärung finden Sie hier:
https://embedded-brains.de/datenschutzerklaerung/
