Wilco Dijkstra <wilco.dijks...@arm.com> writes:
> Hi Richard,
>
>> So rather than have two patterns that generate frintn, I think
>> it would be better to change the existing frint_pattern entry to
>> "roundeven" instead, and fix whatever the fallout is. Hopefully it
>> shouldn't be too bad, since we already use the optab names for the
>> other UNSPEC_FRINT* codes.
>
> Well it requires various changes to the arm_neon headers since they use
> existing intrinsics. If that is not considered a risky ABI change then here is
> v2:
>
> Enable __builtin_roundeven[f] by changing existing frintn to roundeven.
Yeah, changing the arm_neon.h->compiler interface is OK, since we only
support using the version of arm_neon.h that ships with the compiler,
not an older or newer version. There have already been quite a few
changes like that since GCC 11 branched (to get better optimisation).
> Bootstrap OK and passes regress.
>
> ChangeLog:
> 2021-06-18 Wilco Dijkstra <wdijk...@arm.com>
>
> PR target/100966
> * config/aarch64/aarch64.md (frint_pattern): Update comment.
> * config/aarch64/aarch64-simd-builtins.def: Change frintn to
> roundeven.
> * config/aarch64/arm_fp16.h: Change frintn to roundeven.
> * config/aarch64/arm_neon.h: Likewise.
> * config/aarch64/iterators.md (frint_pattern): Use roundeven for
> FRINTN.
>
> gcc/testsuite
> PR target/100966
> * gcc.target/aarch64/frint.x: Add roundeven tests.
> * gcc.target/aarch64/frint_double.c: Likewise.
> * gcc.target/aarch64/frint_float.c: Likewise.
OK, thanks.
Richard
>
> ---
>
> diff --git a/gcc/config/aarch64/aarch64-simd-builtins.def
> b/gcc/config/aarch64/
> aarch64-simd-builtins.def
> index
> b885bd5b38bf7ad83eb9d801284bf9b34db17210..534cc8ccb538c4fb0c208a7035020e131656260d
> 100644
> --- a/gcc/config/aarch64/aarch64-simd-builtins.def
> +++ b/gcc/config/aarch64/aarch64-simd-builtins.def
> @@ -485,7 +485,7 @@
> BUILTIN_VHSDF (UNOP, nearbyint, 2, FP)
> BUILTIN_VHSDF (UNOP, rint, 2, FP)
> BUILTIN_VHSDF (UNOP, round, 2, FP)
> - BUILTIN_VHSDF_HSDF (UNOP, frintn, 2, FP)
> + BUILTIN_VHSDF_HSDF (UNOP, roundeven, 2, FP)
>
> VAR1 (UNOP, btrunc, 2, FP, hf)
> VAR1 (UNOP, ceil, 2, FP, hf)
> diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/aarch64.md
> index
> 30effca6f3562f6870a6cc8097750e63bb0d424d..8977330b142d2cde1d2faa4a01282b01a68e25c5
> 100644
> --- a/gcc/config/aarch64/aarch64.md
> +++ b/gcc/config/aarch64/aarch64.md
> @@ -5922,7 +5922,7 @@ (define_insn "*bswapsi2_uxtw"
> ;; -------------------------------------------------------------------
>
> ;; frint floating-point round to integral standard patterns.
> -;; Expands to btrunc, ceil, floor, nearbyint, rint, round, frintn.
> +;; Expands to btrunc, ceil, floor, nearbyint, rint, round, roundeven.
>
> (define_insn "<frint_pattern><mode>2"
> [(set (match_operand:GPF_F16 0 "register_operand" "=w")
> diff --git a/gcc/config/aarch64/arm_fp16.h b/gcc/config/aarch64/arm_fp16.h
> index
> 2afbd1203361b54d6e1315ffaa1bec21834c060e..3efa7e1f19817df1409bf781266f4e238c128f0b
> 100644
> --- a/gcc/config/aarch64/arm_fp16.h
> +++ b/gcc/config/aarch64/arm_fp16.h
> @@ -333,7 +333,7 @@ vrndmh_f16 (float16_t __a)
> __extension__ static __inline float16_t __attribute__ ((__always_inline__))
> vrndnh_f16 (float16_t __a)
> {
> - return __builtin_aarch64_frintnhf (__a);
> + return __builtin_aarch64_roundevenhf (__a);
> }
>
> __extension__ static __inline float16_t __attribute__ ((__always_inline__))
> diff --git a/gcc/config/aarch64/arm_neon.h b/gcc/config/aarch64/arm_neon.h
> index
> baa30bd5a9d96c1bf04a37fb105091ea56a6444a..c88a8a627d3082d3577b0fe222381e93c35d7251
> 100644
> --- a/gcc/config/aarch64/arm_neon.h
> +++ b/gcc/config/aarch64/arm_neon.h
> @@ -24657,35 +24657,35 @@ __extension__ extern __inline float32_t
> __attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
> vrndns_f32 (float32_t __a)
> {
> - return __builtin_aarch64_frintnsf (__a);
> + return __builtin_aarch64_roundevensf (__a);
> }
>
> __extension__ extern __inline float32x2_t
> __attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
> vrndn_f32 (float32x2_t __a)
> {
> - return __builtin_aarch64_frintnv2sf (__a);
> + return __builtin_aarch64_roundevenv2sf (__a);
> }
>
> __extension__ extern __inline float64x1_t
> __attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
> vrndn_f64 (float64x1_t __a)
> {
> - return (float64x1_t) {__builtin_aarch64_frintndf (__a[0])};
> + return (float64x1_t) {__builtin_aarch64_roundevendf (__a[0])};
> }
>
> __extension__ extern __inline float32x4_t
> __attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
> vrndnq_f32 (float32x4_t __a)
> {
> - return __builtin_aarch64_frintnv4sf (__a);
> + return __builtin_aarch64_roundevenv4sf (__a);
> }
>
> __extension__ extern __inline float64x2_t
> __attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
> vrndnq_f64 (float64x2_t __a)
> {
> - return __builtin_aarch64_frintnv2df (__a);
> + return __builtin_aarch64_roundevenv2df (__a);
> }
>
> /* vrndp */
> @@ -31287,14 +31287,14 @@ __extension__ extern __inline float16x4_t
> __attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
> vrndn_f16 (float16x4_t __a)
> {
> - return __builtin_aarch64_frintnv4hf (__a);
> + return __builtin_aarch64_roundevenv4hf (__a);
> }
>
> __extension__ extern __inline float16x8_t
> __attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
> vrndnq_f16 (float16x8_t __a)
> {
> - return __builtin_aarch64_frintnv8hf (__a);
> + return __builtin_aarch64_roundevenv8hf (__a);
> }
>
> __extension__ extern __inline float16x4_t
> diff --git a/gcc/config/aarch64/iterators.md b/gcc/config/aarch64/iterators.md
> index
> cac33ae812b382cd55611b0da8a6e9eac3a513c4..142823e8b067b0c00d28b3265d6a8061a386c085
> 100644
> --- a/gcc/config/aarch64/iterators.md
> +++ b/gcc/config/aarch64/iterators.md
> @@ -3079,7 +3079,7 @@ (define_int_attr frint_pattern [(UNSPEC_FRINTZ "btrunc")
> (UNSPEC_FRINTI "nearbyint")
> (UNSPEC_FRINTX "rint")
> (UNSPEC_FRINTA "round")
> - (UNSPEC_FRINTN "frintn")])
> + (UNSPEC_FRINTN "roundeven")])
>
> ;; frint suffix for floating-point rounding instructions.
> (define_int_attr frint_suffix [(UNSPEC_FRINTZ "z") (UNSPEC_FRINTP "p")
> diff --git a/gcc/testsuite/gcc.target/aarch64/frint.x b/gcc/testsuite/
> gcc.target/aarch64/frint.x
> index
> 1403740686ea3927d2c39eb2466ef8cc67e223b2..d598a25ff21b8feeca6a96de79848b2fbde7f31e
> 100644
> --- a/gcc/testsuite/gcc.target/aarch64/frint.x
> +++ b/gcc/testsuite/gcc.target/aarch64/frint.x
> @@ -4,6 +4,7 @@ extern GPF SUFFIX(floor) (GPF);
> extern GPF SUFFIX(nearbyint) (GPF);
> extern GPF SUFFIX(rint) (GPF);
> extern GPF SUFFIX(round) (GPF);
> +extern GPF SUFFIX(roundeven) (GPF);
>
> GPF test1a (GPF x)
> {
> @@ -64,3 +65,14 @@ GPF test6b (GPF x)
> {
> return SUFFIX(round)(x);
> }
> +
> +GPF test7a (GPF x)
> +{
> + return SUFFIX(__builtin_roundeven)(x);
> +}
> +
> +GPF test7b (GPF x)
> +{
> + return SUFFIX(roundeven)(x);
> +}
> +
> diff --git a/gcc/testsuite/gcc.target/aarch64/frint_double.c b/gcc/testsuite/
> gcc.target/aarch64/frint_double.c
> index
> 96139496ca454cebd41d31e8b018dab7ffa33a3f..1d28eb09e11842802ab632a7696de4407263f8ce
> 100644
> --- a/gcc/testsuite/gcc.target/aarch64/frint_double.c
> +++ b/gcc/testsuite/gcc.target/aarch64/frint_double.c
> @@ -12,3 +12,4 @@
> /* { dg-final { scan-assembler-times "frinti\td\[0-9\]" 2 } } */
> /* { dg-final { scan-assembler-times "frintx\td\[0-9\]" 2 } } */
> /* { dg-final { scan-assembler-times "frinta\td\[0-9\]" 2 } } */
> +/* { dg-final { scan-assembler-times "frintn\td\[0-9\]" 2 } } */
> diff --git a/gcc/testsuite/gcc.target/aarch64/frint_float.c b/gcc/testsuite/
> gcc.target/aarch64/frint_float.c
> index
> 493ec37f940a6e8cb01ea7e324073fa22099636c..530cf975db3d52c30bce43d0c40229b2b375cdea
> 100644
> --- a/gcc/testsuite/gcc.target/aarch64/frint_float.c
> +++ b/gcc/testsuite/gcc.target/aarch64/frint_float.c
> @@ -12,3 +12,4 @@
> /* { dg-final { scan-assembler-times "frinti\ts\[0-9\]" 2 } } */
> /* { dg-final { scan-assembler-times "frintx\ts\[0-9\]" 2 } } */
> /* { dg-final { scan-assembler-times "frinta\ts\[0-9\]" 2 } } */
> +/* { dg-final { scan-assembler-times "frintn\ts\[0-9\]" 2 } } */
