Hi Kewen,
Although I agree that what we do now is tragically bad (and will be fixed in
the builtin rewrite), this seems a little too cavalier to remove all checking
during initialization without adding any checking somewhere else. :-) We still
need to check for invalid usage when the builtin is expanded, and I don't think
the old code does this at all.
Unless you are planning to do a backport, I think the proper way forward here
is to just wait for the new builtin support to land. In the new code, we
initialize all built-ins up front, and check properly at expansion time whether
the builtin is enabled in the environment that obtains during expand.
My two cents,
Bill
On 9/28/21 3:13 AM, Kewen.Lin wrote:
> Hi,
>
> As the discussion in PR102347, currently builtin_decl is invoked so
> early, it's when making up the function_decl for builtin functions,
> at that time the rs6000_builtin_mask could be wrong for those
> builtins sitting in #pragma/attribute target functions, though it
> will be updated properly later when LTO processes all nodes.
>
> This patch is to align with the practice i386 port adopts, also
> align with r10-7462 by relaxing builtin mask checking in some places.
>
> Bootstrapped and regress-tested on powerpc64le-linux-gnu P9 and
> powerpc64-linux-gnu P8.
>
> Is it ok for trunk?
>
> BR,
> Kewen
> -----
> gcc/ChangeLog:
>
> PR target/102347
> * config/rs6000/rs6000-call.c (rs6000_builtin_decl): Remove builtin
> mask check.
>
> gcc/testsuite/ChangeLog:
>
> PR target/102347
> * gcc.target/powerpc/pr102347.c: New test.
>
> ---
> gcc/config/rs6000/rs6000-call.c | 14 ++++----------
> gcc/testsuite/gcc.target/powerpc/pr102347.c | 15 +++++++++++++++
> 2 files changed, 19 insertions(+), 10 deletions(-)
> create mode 100644 gcc/testsuite/gcc.target/powerpc/pr102347.c
>
> diff --git a/gcc/config/rs6000/rs6000-call.c b/gcc/config/rs6000/rs6000-call.c
> index fd7f24da818..15e0e09c07d 100644
> --- a/gcc/config/rs6000/rs6000-call.c
> +++ b/gcc/config/rs6000/rs6000-call.c
> @@ -13775,23 +13775,17 @@ rs6000_init_builtins (void)
> }
> }
>
> -/* Returns the rs6000 builtin decl for CODE. */
> +/* Returns the rs6000 builtin decl for CODE. Note that we don't check
> + the builtin mask here since there could be some #pragma/attribute
> + target functions and the rs6000_builtin_mask could be wrong when
> + this checking happens, though it will be updated properly later. */
>
> tree
> rs6000_builtin_decl (unsigned code, bool initialize_p ATTRIBUTE_UNUSED)
> {
> - HOST_WIDE_INT fnmask;
> -
> if (code >= RS6000_BUILTIN_COUNT)
> return error_mark_node;
>
> - fnmask = rs6000_builtin_info[code].mask;
> - if ((fnmask & rs6000_builtin_mask) != fnmask)
> - {
> - rs6000_invalid_builtin ((enum rs6000_builtins)code);
> - return error_mark_node;
> - }
> -
> return rs6000_builtin_decls[code];
> }
>
> diff --git a/gcc/testsuite/gcc.target/powerpc/pr102347.c
> b/gcc/testsuite/gcc.target/powerpc/pr102347.c
> new file mode 100644
> index 00000000000..05c439a8dac
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/powerpc/pr102347.c
> @@ -0,0 +1,15 @@
> +/* { dg-do link } */
> +/* { dg-require-effective-target power10_ok } */
> +/* { dg-require-effective-target lto } */
> +/* { dg-options "-flto -mdejagnu-cpu=power9" } */
> +
> +/* Verify there are no error messages in LTO mode. */
> +
> +#pragma GCC target "cpu=power10"
> +int main ()
> +{
> + float *b;
> + __vector_quad c;
> + __builtin_mma_disassemble_acc (b, &c);
> + return 0;
> +}
> --
> 2.27.0
>
