On Tue, 18 Apr 2023, Jakub Jelinek wrote:
> Hi!
>
> match.pd has mostly for AArch64 an optimization in which it optimizes
> certain forms of __builtin_shuffle of x + y and x - y vectors into
> fneg using twice as wide element type so that every other sign is changed,
> followed by fadd.
>
> The following patch extends that optimization, so that it can handle
> other forms as well, using the same fneg but fsub instead of fadd.
>
> As the plus is commutative and minus is not and I want to handle
> vec_perm with plus minus and minus plus order preferrably in one
> pattern, I had to do the matching operand checks by hand.
>
> Bootstrapped/regtested on aarch64-linux, x86_64-linux and i686-linux,
> ok for trunk?
OK.
Thanks,
Richard.
> 2023-04-18 Jakub Jelinek <ja...@redhat.com>
>
> PR tree-optimization/109240
> * match.pd (fneg/fadd): Rewrite such that it handles both plus as
> first vec_perm operand and minus as second using fneg/fadd and
> minus as first vec_perm operand and plus as second using fneg/fsub.
>
> * gcc.target/aarch64/simd/addsub_2.c: New test.
> * gcc.target/aarch64/sve/addsub_2.c: New test.
>
> --- gcc/match.pd.jj 2023-03-21 19:59:40.209634256 +0100
> +++ gcc/match.pd 2023-03-22 10:17:25.344772636 +0100
> @@ -8074,63 +8074,76 @@ and,
> under IEEE 754 the fneg of the wider type will negate every even entry
> and when doing an add we get a sub of the even and add of every odd
> elements. */
> -(simplify
> - (vec_perm (plus:c @0 @1) (minus @0 @1) VECTOR_CST@2)
> - (if (!VECTOR_INTEGER_TYPE_P (type)
> - && !FLOAT_WORDS_BIG_ENDIAN)
> - (with
> - {
> - /* Build a vector of integers from the tree mask. */
> - vec_perm_builder builder;
> - }
> - (if (tree_to_vec_perm_builder (&builder, @2))
> - (with
> - {
> - /* Create a vec_perm_indices for the integer vector. */
> - poly_uint64 nelts = TYPE_VECTOR_SUBPARTS (type);
> - vec_perm_indices sel (builder, 2, nelts);
> - machine_mode vec_mode = TYPE_MODE (type);
> - machine_mode wide_mode;
> - scalar_mode wide_elt_mode;
> - poly_uint64 wide_nunits;
> - scalar_mode inner_mode = GET_MODE_INNER (vec_mode);
> - }
> - (if (sel.series_p (0, 2, 0, 2)
> - && sel.series_p (1, 2, nelts + 1, 2)
> - && GET_MODE_2XWIDER_MODE (inner_mode).exists (&wide_elt_mode)
> - && multiple_p (GET_MODE_NUNITS (vec_mode), 2, &wide_nunits)
> - && related_vector_mode (vec_mode, wide_elt_mode,
> - wide_nunits).exists (&wide_mode))
> - (with
> - {
> - tree stype
> - = lang_hooks.types.type_for_mode (GET_MODE_INNER (wide_mode),
> - TYPE_UNSIGNED (type));
> - tree ntype = build_vector_type_for_mode (stype, wide_mode);
> +(for plusminus (plus minus)
> + minusplus (minus plus)
> + (simplify
> + (vec_perm (plusminus @0 @1) (minusplus @2 @3) VECTOR_CST@4)
> + (if (!VECTOR_INTEGER_TYPE_P (type)
> + && !FLOAT_WORDS_BIG_ENDIAN
> + /* plus is commutative, while minus is not, so :c can't be used.
> + Do equality comparisons by hand and at the end pick the operands
> + from the minus. */
> + && (operand_equal_p (@0, @2, 0)
> + ? operand_equal_p (@1, @3, 0)
> + : operand_equal_p (@0, @3, 0) && operand_equal_p (@1, @2, 0)))
> + (with
> + {
> + /* Build a vector of integers from the tree mask. */
> + vec_perm_builder builder;
> + }
> + (if (tree_to_vec_perm_builder (&builder, @4))
> + (with
> + {
> + /* Create a vec_perm_indices for the integer vector. */
> + poly_uint64 nelts = TYPE_VECTOR_SUBPARTS (type);
> + vec_perm_indices sel (builder, 2, nelts);
> + machine_mode vec_mode = TYPE_MODE (type);
> + machine_mode wide_mode;
> + scalar_mode wide_elt_mode;
> + poly_uint64 wide_nunits;
> + scalar_mode inner_mode = GET_MODE_INNER (vec_mode);
> + }
> + (if (sel.series_p (0, 2, 0, 2)
> + && sel.series_p (1, 2, nelts + 1, 2)
> + && GET_MODE_2XWIDER_MODE (inner_mode).exists (&wide_elt_mode)
> + && multiple_p (GET_MODE_NUNITS (vec_mode), 2, &wide_nunits)
> + && related_vector_mode (vec_mode, wide_elt_mode,
> + wide_nunits).exists (&wide_mode))
> + (with
> + {
> + tree stype
> + = lang_hooks.types.type_for_mode (GET_MODE_INNER (wide_mode),
> + TYPE_UNSIGNED (type));
> + tree ntype = build_vector_type_for_mode (stype, wide_mode);
>
> - /* The format has to be a non-extended ieee format. */
> - const struct real_format *fmt_old = FLOAT_MODE_FORMAT (vec_mode);
> - const struct real_format *fmt_new = FLOAT_MODE_FORMAT (wide_mode);
> - }
> - (if (TYPE_MODE (stype) != BLKmode
> - && VECTOR_TYPE_P (ntype)
> - && fmt_old != NULL
> - && fmt_new != NULL)
> - (with
> - {
> - /* If the target doesn't support v1xx vectors, try using
> - scalar mode xx instead. */
> + /* The format has to be a non-extended ieee format. */
> + const struct real_format *fmt_old = FLOAT_MODE_FORMAT (vec_mode);
> + const struct real_format *fmt_new = FLOAT_MODE_FORMAT (wide_mode);
> + }
> + (if (TYPE_MODE (stype) != BLKmode
> + && VECTOR_TYPE_P (ntype)
> + && fmt_old != NULL
> + && fmt_new != NULL)
> + (with
> + {
> + /* If the target doesn't support v1xx vectors, try using
> + scalar mode xx instead. */
> if (known_eq (GET_MODE_NUNITS (wide_mode), 1)
> && !target_supports_op_p (ntype, NEGATE_EXPR, optab_vector))
> ntype = stype;
> - }
> - (if (fmt_new->signbit_rw
> - == fmt_old->signbit_rw + GET_MODE_UNIT_BITSIZE (vec_mode)
> - && fmt_new->signbit_rw == fmt_new->signbit_ro
> - && targetm.can_change_mode_class (TYPE_MODE (ntype), TYPE_MODE
> (type), ALL_REGS)
> - && ((optimize_vectors_before_lowering_p () && VECTOR_TYPE_P
> (ntype))
> - || target_supports_op_p (ntype, NEGATE_EXPR, optab_vector)))
> - (plus (view_convert:type (negate (view_convert:ntype @1)))
> @0)))))))))))
> + }
> + (if (fmt_new->signbit_rw
> + == fmt_old->signbit_rw + GET_MODE_UNIT_BITSIZE (vec_mode)
> + && fmt_new->signbit_rw == fmt_new->signbit_ro
> + && targetm.can_change_mode_class (TYPE_MODE (ntype),
> + TYPE_MODE (type), ALL_REGS)
> + && ((optimize_vectors_before_lowering_p ()
> + && VECTOR_TYPE_P (ntype))
> + || target_supports_op_p (ntype, NEGATE_EXPR, optab_vector)))
> + (if (plusminus == PLUS_EXPR)
> + (plus (view_convert:type (negate (view_convert:ntype @3))) @2)
> + (minus @0 (view_convert:type
> + (negate (view_convert:ntype @1))))))))))))))))
>
> (simplify
> (vec_perm @0 @1 VECTOR_CST@2)
> --- gcc/testsuite/gcc.target/aarch64/simd/addsub_2.c.jj 2023-03-22
> 10:22:57.324017790 +0100
> +++ gcc/testsuite/gcc.target/aarch64/simd/addsub_2.c 2023-03-22
> 10:23:54.482199126 +0100
> @@ -0,0 +1,56 @@
> +/* { dg-do compile } */
> +/* { dg-require-effective-target arm_v8_2a_fp16_neon_ok } */
> +/* { dg-options "-Ofast" } */
> +/* { dg-add-options arm_v8_2a_fp16_neon } */
> +/* { dg-final { check-function-bodies "**" "" "" { target { le } } } } */
> +
> +#pragma GCC target "+nosve"
> +
> +/*
> +** f1:
> +** ...
> +** fneg v[0-9]+.2d, v[0-9]+.2d
> +** fsub v[0-9]+.4s, v[0-9]+.4s, v[0-9]+.4s
> +** ...
> +*/
> +void f1 (float *restrict a, float *restrict b, float *res, int n)
> +{
> + for (int i = 0; i < (n & -4); i+=2)
> + {
> + res[i+0] = a[i+0] - b[i+0];
> + res[i+1] = a[i+1] + b[i+1];
> + }
> +}
> +
> +/*
> +** d1:
> +** ...
> +** fneg v[0-9]+.4s, v[0-9]+.4s
> +** fsub v[0-9]+.8h, v[0-9]+.8h, v[0-9]+.8h
> +** ...
> +*/
> +void d1 (_Float16 *restrict a, _Float16 *restrict b, _Float16 *res, int n)
> +{
> + for (int i = 0; i < (n & -8); i+=2)
> + {
> + res[i+0] = a[i+0] - b[i+0];
> + res[i+1] = a[i+1] + b[i+1];
> + }
> +}
> +
> +/*
> +** e1:
> +** ...
> +** fsub v[0-9]+.2d, v[0-9]+.2d, v[0-9]+.2d
> +** fadd v[0-9]+.2d, v[0-9]+.2d, v[0-9]+.2d
> +** ins v[0-9]+.d\[1\], v[0-9]+.d\[1\]
> +** ...
> +*/
> +void e1 (double *restrict a, double *restrict b, double *res, int n)
> +{
> + for (int i = 0; i < (n & -4); i+=2)
> + {
> + res[i+0] = a[i+0] - b[i+0];
> + res[i+1] = a[i+1] + b[i+1];
> + }
> +}
> --- gcc/testsuite/gcc.target/aarch64/sve/addsub_2.c.jj 2023-03-22
> 10:24:14.169917153 +0100
> +++ gcc/testsuite/gcc.target/aarch64/sve/addsub_2.c 2023-03-22
> 10:25:05.414183194 +0100
> @@ -0,0 +1,52 @@
> +/* { dg-do compile } */
> +/* { dg-options "-Ofast" } */
> +/* { dg-final { check-function-bodies "**" "" "" { target { le } } } } */
> +
> +/*
> +** f1:
> +** ...
> +** fneg z[0-9]+.d, p[0-9]+/m, z[0-9]+.d
> +** fsub z[0-9]+.s, z[0-9]+.s, z[0-9]+.s
> +** ...
> +*/
> +void f1 (float *restrict a, float *restrict b, float *res, int n)
> +{
> + for (int i = 0; i < (n & -4); i+=2)
> + {
> + res[i+0] = a[i+0] - b[i+0];
> + res[i+1] = a[i+1] + b[i+1];
> + }
> +}
> +
> +/*
> +** d1:
> +** ...
> +** fneg z[0-9]+.s, p[0-9]+/m, z[0-9]+.s
> +** fsub z[0-9]+.h, z[0-9]+.h, z[0-9]+.h
> +** ...
> +*/
> +void d1 (_Float16 *restrict a, _Float16 *restrict b, _Float16 *res, int n)
> +{
> + for (int i = 0; i < (n & -8); i+=2)
> + {
> + res[i+0] = a[i+0] - b[i+0];
> + res[i+1] = a[i+1] + b[i+1];
> + }
> +}
> +
> +/*
> +** e1:
> +** ...
> +** fadd z[0-9]+.d, z[0-9]+.d, z[0-9]+.d
> +** movprfx z[0-9]+.d, p[0-9]+/m, z[0-9]+.d
> +** fsub z[0-9]+.d, p[0-9]+/m, z[0-9]+.d, z[0-9]+.d
> +** ...
> +*/
> +void e1 (double *restrict a, double *restrict b, double *res, int n)
> +{
> + for (int i = 0; i < (n & -4); i+=2)
> + {
> + res[i+0] = a[i+0] - b[i+0];
> + res[i+1] = a[i+1] + b[i+1];
> + }
> +}
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg,
Germany; GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman;
HRB 36809 (AG Nuernberg)
