[PATCH][Fortran][v2] Use MIN/MAX_EXPR for min/max intrinsics

[Kyrill Tkachov]

Hi Richard,

On 18/07/18 16:27, Richard Sandiford wrote:
> Thanks for doing this.
>
> Kyrill  Tkachov <kyrylo.tkachov@foss.arm.com> writes:
>> +	  calc = build_call_expr_internal_loc (input_location, ifn, type,
>> +				      2, mvar, convert (type, val));
> (indentation looks off)
>
>> diff --git a/gcc/testsuite/gfortran.dg/max_fmaxl_aarch64.f90 b/gcc/testsuite/gfortran.dg/max_fmaxl_aarch64.f90
>> new file mode 100644
>> index 0000000000000000000000000000000000000000..8c8ea063e5d0718dc829c1f5574c5b46040e6786
>> --- /dev/null
>> +++ b/gcc/testsuite/gfortran.dg/max_fmaxl_aarch64.f90
>> @@ -0,0 +1,9 @@
>> +! { dg-do compile { target aarch64*-*-* } }
>> +! { dg-options "-O2 -fdump-tree-optimized" }
>> +
>> +subroutine fool (a, b, c, d, e, f, g, h)
>> +  real (kind=16) :: a, b, c, d, e, f, g, h
>> +  a = max (a, b, c, d, e, f, g, h)
>> +end subroutine
>> +
>> +! { dg-final { scan-tree-dump-times "__builtin_fmaxl " 7 "optimized" } }
>> diff --git a/gcc/testsuite/gfortran.dg/min_fminl_aarch64.f90 b/gcc/testsuite/gfortran.dg/min_fminl_aarch64.f90
>> new file mode 100644
>> index 0000000000000000000000000000000000000000..92368917fb48e0c468a16d080ab3a9ac842e01a7
>> --- /dev/null
>> +++ b/gcc/testsuite/gfortran.dg/min_fminl_aarch64.f90
>> @@ -0,0 +1,9 @@
>> +! { dg-do compile { target aarch64*-*-* } }
>> +! { dg-options "-O2 -fdump-tree-optimized" }
>> +
>> +subroutine fool (a, b, c, d, e, f, g, h)
>> +  real (kind=16) :: a, b, c, d, e, f, g, h
>> +  a = min (a, b, c, d, e, f, g, h)
>> +end subroutine
>> +
>> +! { dg-final { scan-tree-dump-times "__builtin_fminl " 7 "optimized" } }
> Do these still pass?  I wouldn't have expected us to use __builtin_fmin*
> and __builtin_fmax* now.
>
> It would be good to have tests that we use ".FMIN" and ".FMAX" for kind=4
> and kind=8 on AArch64, since that's really the end goal here.

Doh, yes. I had spotted that myself after I had sent out the patch.
I've fixed that and the indentation issue in this small revision.

Given Janne's comments I will commit this tomorrow if there are no objections.
This patch should be a conservative improvement. If the Fortran folks decide
to sacrifice the more predictable NaN handling in favour of more optimisation
leeway by using MIN/MAX_EXPR unconditionally we can do that as a follow-up.

Thanks for the help,
Kyrill

2018-07-18  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

     * trans-intrinsic.c: (gfc_conv_intrinsic_minmax): Emit MIN_MAX_EXPR
     or IFN_FMIN/FMAX sequence to calculate the min/max when possible.

2018-07-18  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

     * gfortran.dg/max_fmax_aarch64.f90: New test.
     * gfortran.dg/min_fmin_aarch64.f90: Likewise.
     * gfortran.dg/minmax_integer.f90: Likewise.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: fort-v4.patch
Type: text/x-patch
Size: 7360 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/gcc-patches/attachments/20180718/1dfb1e33/attachment.bin>