Re: [RFC PATCH v2 4/5] tests/tcg/ppc64le: emit bcdsub with .long when needed

[Richard Henderson <richard.henderson@linaro.org>]

On 3/3/22 07:20, matheus.ferst@eldorado.org.br wrote:
> From: Matheus Ferst<matheus.ferst@eldorado.org.br>
> 
> Based on GCC docs[1], we use the '-mpower8-vector' flag at config-time
> to detect the toolchain support to the bcdsub instruction. LLVM/Clang
> supports this flag since version 3.6[2], but the instruction and related
> builtins were only added in LLVM 14[3]. In the absence of other means to
> detect this support at config-time, we resort to __has_builtin to
> identify the presence of __builtin_bcdsub at compile-time. If the
> builtin is not available, the instruction is emitted with a ".long".
> 
> [1]https://gcc.gnu.org/onlinedocs/gcc-8.3.0/gcc/PowerPC-AltiVec_002fVSX-Built-in-Functions.html
> [2]https://github.com/llvm/llvm-project/commit/59eb767e11d4ffefb5f55409524e5c8416b2b0db
> [3]https://github.com/llvm/llvm-project/commit/c933c2eb334660c131f4afc9d194fafb0cec0423
> 
> Signed-off-by: Matheus Ferst<matheus.ferst@eldorado.org.br>
> ---
>   tests/tcg/ppc64le/bcdsub.c | 55 +++++++++++++++++++++-----------------
>   1 file changed, 30 insertions(+), 25 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~