On Mon, Jun 26, 2023 at 4:36 AM Hongyu Wang <hongyu.w...@intel.com> wrote:
>
> Hi,
>
> For function with different target attributes, current logic rejects to
> inline the callee when any arch or tune is mismatched. Relax the
> condition to honor just prefer_vecotr_width_type and other flags that
> may cause safety issue so caller can get more optimization opportunity.
I don't think this is desirable. If we inline something with different
ISAs, we get some strange mix of ISAs when the function is inlined.
OTOH - we already inline with mismatched tune flags if the function is
marked with always_inline.
Uros.
> Bootstrapped/regtested on x86_64-pc-linux-gnu{-m32,}
>
> Ok for trunk?
>
> gcc/ChangeLog:
>
> * config/i386/i386.cc (ix86_can_inline_p): Do not check arch or
> tune directly, just check prefer_vector_width_type and make sure
> not to inline if they mismatch.
>
> gcc/testsuite/ChangeLog:
>
> * gcc.target/i386/inline-target-attr.c: New test.
> ---
> gcc/config/i386/i386.cc | 11 +++++----
> .../gcc.target/i386/inline-target-attr.c | 24 +++++++++++++++++++
> 2 files changed, 30 insertions(+), 5 deletions(-)
> create mode 100644 gcc/testsuite/gcc.target/i386/inline-target-attr.c
>
> diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
> index 0761965344b..1d86384ac06 100644
> --- a/gcc/config/i386/i386.cc
> +++ b/gcc/config/i386/i386.cc
> @@ -605,11 +605,12 @@ ix86_can_inline_p (tree caller, tree callee)
> != (callee_opts->x_target_flags & ~always_inline_safe_mask))
> ret = false;
>
> - /* See if arch, tune, etc. are the same. */
> - else if (caller_opts->arch != callee_opts->arch)
> - ret = false;
> -
> - else if (!always_inline && caller_opts->tune != callee_opts->tune)
> + /* Do not inline when specified perfer-vector-width mismatched between
> + callee and caller. */
> + else if ((callee_opts->x_prefer_vector_width_type != PVW_NONE
> + && caller_opts->x_prefer_vector_width_type != PVW_NONE)
> + && callee_opts->x_prefer_vector_width_type
> + != caller_opts->x_prefer_vector_width_type)
> ret = false;
>
> else if (caller_opts->x_ix86_fpmath != callee_opts->x_ix86_fpmath
> diff --git a/gcc/testsuite/gcc.target/i386/inline-target-attr.c
> b/gcc/testsuite/gcc.target/i386/inline-target-attr.c
> new file mode 100644
> index 00000000000..995502165f0
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/i386/inline-target-attr.c
> @@ -0,0 +1,24 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2" } */
> +/* { dg-final { scan-assembler-not "call\[ \t\]callee" } } */
> +
> +__attribute__((target("arch=skylake")))
> +int callee (int n)
> +{
> + int sum = 0;
> + for (int i = 0; i < n; i++)
> + {
> + if (i % 2 == 0)
> + sum +=i;
> + else
> + sum += (i - 1);
> + }
> + return sum + n;
> +}
> +
> +__attribute__((target("arch=icelake-server")))
> +int caller (int n)
> +{
> + return callee (n) + n;
> +}
> +
> --
> 2.31.1
>
