Re: Fix vect_float markup for a couple of tests (PR 83888)

[Richard Biener <richard dot guenther at gmail dot com>]

On Mon, Jan 22, 2018 at 6:55 PM, Richard Sandiford
<richard.sandiford@linaro.org> wrote:
> vect_float is true for arm*-*-* targets, but the support is only
> available when -funsafe-math-optimizations is on.  This caused
> failures in two tests that disable fast-math.
>
> The easiest fix seemed to be to add a new target selector for
> "vect_float without special options".
>
> Tested on aarch64-linux-gnu, x86_64-linux-gnu and powerpc64le-linux-gnu.
> OK to install?

Ok - so arm float vectors are not IEEE compliant?

Richard.

> Richard
>
>
> 2018-01-22  Richard Sandiford  <richard.sandiford@linaro.org>
>
> gcc/
>         PR testsuite/83888
>         * doc/sourcebuild.texi (vect_float): Say that the selector
>         only describes the situation when -funsafe-math-optimizations is on.
>         (vect_float_strict): Document.
>
> gcc/testsuite/
>         PR testsuite/83888
>         * lib/target-supports.exp (check_effective_target_vect_float): Say
>         that the result only holds when -funsafe-math-optimizations is on.
>         (check_effective_target_vect_float_strict): New procedure.
>         * gcc.dg/vect/no-fast-math-vect16.c: Use vect_float_strict instead
>         of vect_float.
>         * gcc.dg/vect/vect-reduc-6.c: Likewise.
>
> Index: gcc/doc/sourcebuild.texi
> ===================================================================
> --- gcc/doc/sourcebuild.texi    2018-01-22 17:51:03.860579049 +0000
> +++ gcc/doc/sourcebuild.texi    2018-01-22 17:54:02.172848564 +0000
> @@ -1403,7 +1403,13 @@ The target's preferred vector alignment
>  alignment.
>
>  @item vect_float
> -Target supports hardware vectors of @code{float}.
> +Target supports hardware vectors of @code{float} when
> +@option{-funsafe-math-optimizations} is in effect.
> +
> +@item vect_float_strict
> +Target supports hardware vectors of @code{float} when
> +@option{-funsafe-math-optimizations} is not in effect.
> +This implies @code{vect_float}.
>
>  @item vect_int
>  Target supports hardware vectors of @code{int}.
> Index: gcc/testsuite/lib/target-supports.exp
> ===================================================================
> --- gcc/testsuite/lib/target-supports.exp       2018-01-22 17:51:03.817580787 +0000
> +++ gcc/testsuite/lib/target-supports.exp       2018-01-22 17:54:02.173848531 +0000
> @@ -5492,7 +5492,8 @@ proc check_effective_target_vect_long {
>      return $answer
>  }
>
> -# Return 1 if the target supports hardware vectors of float, 0 otherwise.
> +# Return 1 if the target supports hardware vectors of float when
> +# -funsafe-math-optimizations is enabled, 0 otherwise.
>  #
>  # This won't change for different subtargets so cache the result.
>
> @@ -5525,6 +5526,14 @@ proc check_effective_target_vect_float {
>      return $et_vect_float_saved($et_index)
>  }
>
> +# Return 1 if the target supports hardware vectors of float without
> +# -funsafe-math-optimizations being enabled, 0 otherwise.
> +
> +proc check_effective_target_vect_float_strict { } {
> +    return [expr { [check_effective_target_vect_float]
> +                  && ![istarget arm*-*-*] }]
> +}
> +
>  # Return 1 if the target supports hardware vectors of double, 0 otherwise.
>  #
>  # This won't change for different subtargets so cache the result.
> Index: gcc/testsuite/gcc.dg/vect/no-fast-math-vect16.c
> ===================================================================
> --- gcc/testsuite/gcc.dg/vect/no-fast-math-vect16.c     2018-01-13 18:01:15.293116922 +0000
> +++ gcc/testsuite/gcc.dg/vect/no-fast-math-vect16.c     2018-01-22 17:54:02.172848564 +0000
> @@ -1,4 +1,4 @@
> -/* { dg-require-effective-target vect_float } */
> +/* { dg-require-effective-target vect_float_strict } */
>
>  #include <stdarg.h>
>  #include "tree-vect.h"
> Index: gcc/testsuite/gcc.dg/vect/vect-reduc-6.c
> ===================================================================
> --- gcc/testsuite/gcc.dg/vect/vect-reduc-6.c    2018-01-13 18:01:15.294116882 +0000
> +++ gcc/testsuite/gcc.dg/vect/vect-reduc-6.c    2018-01-22 17:54:02.172848564 +0000
> @@ -1,4 +1,4 @@
> -/* { dg-require-effective-target vect_float } */
> +/* { dg-require-effective-target vect_float_strict } */
>  /* { dg-additional-options "-fno-fast-math" } */
>
>  #include <stdarg.h>