On Tue, Jun 14, 2022 at 12:25 PM H.J. Lu <hjl.to...@gmail.com> wrote:
>
> Disallow siball when calling ifunc functions with PIC register so that
> PIC register can be restored.
>
> gcc/
>
> PR target/105960
> * config/i386/i386.cc (ix86_function_ok_for_sibcall): Return
> false if PIC register is used when calling ifunc functions.
>
> gcc/testsuite/
>
> PR target/105960
> * gcc.target/i386/pr105960.c: New test.
> ---
> gcc/config/i386/i386.cc | 9 +++++++++
> gcc/testsuite/gcc.target/i386/pr105960.c | 19 +++++++++++++++++++
> 2 files changed, 28 insertions(+)
> create mode 100644 gcc/testsuite/gcc.target/i386/pr105960.c
>
> diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
> index 3d189e124e4..1ca7836e11e 100644
> --- a/gcc/config/i386/i386.cc
> +++ b/gcc/config/i386/i386.cc
> @@ -1015,6 +1015,15 @@ ix86_function_ok_for_sibcall (tree decl, tree exp)
> }
> }
>
> + if (decl && ix86_use_pseudo_pic_reg ())
> + {
> + /* When PIC register is used, it must be restored after ifunc
> + function returns. */
> + cgraph_node *node = cgraph_node::get (decl);
> + if (node && node->ifunc_resolver)
> + return false;
> + }
> +
> /* Otherwise okay. That also includes certain types of indirect calls. */
> return true;
> }
> diff --git a/gcc/testsuite/gcc.target/i386/pr105960.c
> b/gcc/testsuite/gcc.target/i386/pr105960.c
> new file mode 100644
> index 00000000000..db137a1642d
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/i386/pr105960.c
> @@ -0,0 +1,19 @@
> +/* { dg-do compile } */
> +/* { dg-require-ifunc "" } */
> +/* { dg-options "-O2 -fpic" } */
> +
> +__attribute__((target_clones("default","fma")))
> +static inline double
> +expfull_ref(double x)
> +{
> + return __builtin_pow(x, 0.1234);
> +}
> +
> +double
> +exp_ref(double x)
> +{
> + return expfull_ref(x);
> +}
> +
> +/* { dg-final { scan-assembler "jmp\[ \t\]*expfull_ref@PLT" { target { !
> ia32 } } } } */
> +/* { dg-final { scan-assembler "call\[ \t\]*expfull_ref@PLT" { target ia32 }
> } } */
> --
> 2.36.1
>
PING.
--
H.J.
