[PATCH] PR target/67995: __attribute__ ((target("arch=XXX"))) enables unsupported ISA

[Uros Bizjak]

On Sat, Oct 17, 2015 at 12:38 AM, H.J. Lu <hongjiu.lu@intel.com> wrote:
> When processing __attribute__ ((target("arch=XXX"))), we should clear
> the ISA bits in x_ix86_isa_flags first to avoid leaking ISA from
> command line.
>
> Tested on x86-64.  OK for trunk?

OK.

Thanks,
Uros.

> Thanks.
>
> H.J.
> ---
> gcc/
>
>         PR target/67995
>         * config/i386/i386.c (ix86_valid_target_attribute_tree): If
>         arch= is set,  clear all bits in x_ix86_isa_flags, except for
>         ISA_64BIT, ABI_64, ABI_X32, and CODE16.
>
> gcc/testsuite/
>
>         PR target/67995
>         * gcc.target/i386/pr67995-1.c: New test.
>         * gcc.target/i386/pr67995-2.c: Likewise.
>         * gcc.target/i386/pr67995-3.c: Likewise.
> ---
>  gcc/config/i386/i386.c                    | 13 ++++++++++++-
>  gcc/testsuite/gcc.target/i386/pr67995-1.c | 16 ++++++++++++++++
>  gcc/testsuite/gcc.target/i386/pr67995-2.c | 16 ++++++++++++++++
>  gcc/testsuite/gcc.target/i386/pr67995-3.c | 16 ++++++++++++++++
>  4 files changed, 60 insertions(+), 1 deletion(-)
>  create mode 100644 gcc/testsuite/gcc.target/i386/pr67995-1.c
>  create mode 100644 gcc/testsuite/gcc.target/i386/pr67995-2.c
>  create mode 100644 gcc/testsuite/gcc.target/i386/pr67995-3.c
>
> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
> index d0e1f4c..b0281c9 100644
> --- a/gcc/config/i386/i386.c
> +++ b/gcc/config/i386/i386.c
> @@ -6145,7 +6145,18 @@ ix86_valid_target_attribute_tree (tree args,
>        /* If we are using the default tune= or arch=, undo the string assigned,
>          and use the default.  */
>        if (option_strings[IX86_FUNCTION_SPECIFIC_ARCH])
> -       opts->x_ix86_arch_string = option_strings[IX86_FUNCTION_SPECIFIC_ARCH];
> +       {
> +         opts->x_ix86_arch_string
> +           = option_strings[IX86_FUNCTION_SPECIFIC_ARCH];
> +
> +         /* If arch= is set,  clear all bits in x_ix86_isa_flags,
> +            except for ISA_64BIT, ABI_64, ABI_X32, and CODE16.  */
> +         opts->x_ix86_isa_flags &= (OPTION_MASK_ISA_64BIT
> +                                    | OPTION_MASK_ABI_64
> +                                    | OPTION_MASK_ABI_X32
> +                                    | OPTION_MASK_CODE16);
> +
> +       }
>        else if (!orig_arch_specified)
>         opts->x_ix86_arch_string = NULL;
>
> diff --git a/gcc/testsuite/gcc.target/i386/pr67995-1.c b/gcc/testsuite/gcc.target/i386/pr67995-1.c
> new file mode 100644
> index 0000000..072b1fe
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/i386/pr67995-1.c
> @@ -0,0 +1,16 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -march=haswell" } */
> +
> +unsigned int
> +__attribute__ ((target("arch=core2")))
> +__x86_rdrand(void)
> +{
> +  unsigned int retries = 100;
> +  unsigned int val;
> +
> +  while (__builtin_ia32_rdrand32_step(&val) == 0) /* { dg-error "needs isa option" } */
> +    if (--retries == 0)
> +      return 0;
> +
> +  return val;
> +}
> diff --git a/gcc/testsuite/gcc.target/i386/pr67995-2.c b/gcc/testsuite/gcc.target/i386/pr67995-2.c
> new file mode 100644
> index 0000000..632bb63
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/i386/pr67995-2.c
> @@ -0,0 +1,16 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -march=core2" } */
> +
> +unsigned int
> +__attribute__ ((target("arch=haswell")))
> +__x86_rdrand(void)
> +{
> +  unsigned int retries = 100;
> +  unsigned int val;
> +
> +  while (__builtin_ia32_rdrand32_step(&val) == 0)
> +    if (--retries == 0)
> +      return 0;
> +
> +  return val;
> +}
> diff --git a/gcc/testsuite/gcc.target/i386/pr67995-3.c b/gcc/testsuite/gcc.target/i386/pr67995-3.c
> new file mode 100644
> index 0000000..11993b7
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/i386/pr67995-3.c
> @@ -0,0 +1,16 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -march=core2" } */
> +
> +unsigned int
> +__attribute__ ((target("rdrnd")))
> +__x86_rdrand(void)
> +{
> +  unsigned int retries = 100;
> +  unsigned int val;
> +
> +  while (__builtin_ia32_rdrand32_step(&val) == 0)
> +    if (--retries == 0)
> +      return 0;
> +
> +  return val;
> +}
> --
> 2.4.3
>