Re: [Patch] GCN: Implement __atomic_compare_exchange_{1, 2} in libgcc [PR102215]

[Andrew Stubbs <ams@codesourcery.com>]

On 09/03/2022 16:29, Tobias Burnus wrote:
> This shows up with with OpenMP offloading as libgomp since a couple
> of months uses __atomic_compare_exchange (see PR for details),
> causing link errors when the gcn libgomp.a is linked.
> It also shows up with sollve_vv.
> 
> The implementation does a bit copy'n'paste from the current
> implementation + calls the existing word/uint32_t-wide version
> of the atomic intrinsic. The semantic is described at
> https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html
> 
> In terms of the args, the _4 has:
> DEF_SYNC_BUILTIN (BUILT_IN_ATOMIC_COMPARE_EXCHANGE_4,
>                    "__atomic_compare_exchange_4",
>                    BT_FN_BOOL_VPTR_PTR_I4_BOOL_INT_INT,
>                    ATTR_NOTHROWCALL_LEAF_LIST)
> and the arg names try to match the GCC manual.
> 
> 
> OK for mainline?
> Tested with libgomp + sollve_vv and -march=gfx908.

OK.

Andrew