Re: [PATCH] Add support for vector conitional not

[Richard Sandiford <richard.sandiford@arm.com>]

Andrew Pinski via Gcc-patches <gcc-patches@gcc.gnu.org> writes:
> Like the support conditional neg (r12-4470-g20dcda98ed376cb61c74b2c71),
> this just adds conditional not too.
> Also we should be able to turn `(a ? -1 : 0) ^ b` into a conditional
> not.
>
> OK? Bootstrapped and tested on x86_64-linux-gnu and aarch64-linux-gnu.
>
> gcc/ChangeLog:
>
> 	* internal-fn.def (COND_NOT): New internal function.
> 	* match.pd (UNCOND_UNARY, COND_UNARY): Add bit_not/not
> 	to the lists.
> 	(`vec (a ? -1 : 0) ^ b`): New pattern to convert
> 	into conditional not.
> 	* optabs.def (cond_one_cmpl): New optab.
> 	(cond_len_one_cmpl): Likewise.
>
> gcc/testsuite/ChangeLog:
>
> 	PR target/110986
> 	* gcc.target/aarch64/sve/cond_unary_9.c: New test.
> ---
>  gcc/internal-fn.def                           |  2 ++
>  gcc/match.pd                                  | 15 ++++++++++++--
>  gcc/optabs.def                                |  2 ++
>  .../gcc.target/aarch64/sve/cond_unary_9.c     | 20 +++++++++++++++++++
>  4 files changed, 37 insertions(+), 2 deletions(-)
>  create mode 100644 gcc/testsuite/gcc.target/aarch64/sve/cond_unary_9.c
>
> diff --git a/gcc/internal-fn.def b/gcc/internal-fn.def
> index b3c410f4b6a..3e8693dfddb 100644
> --- a/gcc/internal-fn.def
> +++ b/gcc/internal-fn.def
> @@ -69,6 +69,7 @@ along with GCC; see the file COPYING3.  If not see
>       lround<srcmode><dstmode>2.
>  
>     - cond_binary: a conditional binary optab, such as cond_add<mode>
> +   - cond_unary: a conditional unary optab, such as cond_neg<mode>
>     - cond_ternary: a conditional ternary optab, such as cond_fma_rev<mode>
>  
>     - fold_left: for scalar = FN (scalar, vector), keyed off the vector mode
> @@ -276,6 +277,7 @@ DEF_INTERNAL_COND_FN (FNMA, ECF_CONST, fnma, ternary)
>  DEF_INTERNAL_COND_FN (FNMS, ECF_CONST, fnms, ternary)
>  
>  DEF_INTERNAL_COND_FN (NEG, ECF_CONST, neg, unary)
> +DEF_INTERNAL_COND_FN (NOT, ECF_CONST, one_cmpl, unary)
>  
>  DEF_INTERNAL_OPTAB_FN (RSQRT, ECF_CONST, rsqrt, unary)
>  
> diff --git a/gcc/match.pd b/gcc/match.pd
> index 6791060891d..2ee6d24ccee 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -84,9 +84,9 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
>  
>  /* Unary operations and their associated IFN_COND_* function.  */
>  (define_operator_list UNCOND_UNARY
> -  negate)
> +  negate bit_not)
>  (define_operator_list COND_UNARY
> -  IFN_COND_NEG)
> +  IFN_COND_NEG IFN_COND_NOT)
>  
>  /* Binary operations and their associated IFN_COND_* function.  */
>  (define_operator_list UNCOND_BINARY
> @@ -8482,6 +8482,17 @@ and,
>          && is_truth_type_for (op_type, TREE_TYPE (@0)))
>       (cond_op (bit_not @0) @2 @1)))))
>  
> +/* `(a ? -1 : 0) ^ b` can be converted into a conditional not.  */
> +(simplify
> + (bit_xor:c (vec_cond @0 uniform_integer_cst_p@1 uniform_integer_cst_p@2) @3)
> + (if (canonicalize_math_after_vectorization_p ()
> +      && vectorized_internal_fn_supported_p (IFN_COND_NOT, type)
> +      && is_truth_type_for (type, TREE_TYPE (@0)))
> + (if (integer_all_onesp (@1) && integer_zerop (@2))
> +  (IFN_COND_NOT @0 @3 @3))
> +  (if (integer_all_onesp (@2) && integer_zerop (@1))
> +   (vec_cond (bit_not @0) @3 @3))))

Looks like this should be IFN_COND_NOT rather than vec_cond.

LGTM otherwise, but please give Richi 24hrs to comment.

Thanks,
Richard

> +
>  /* Simplify:
>  
>       a = a1 op a2
> diff --git a/gcc/optabs.def b/gcc/optabs.def
> index 1ea1947b3b5..a58819bc665 100644
> --- a/gcc/optabs.def
> +++ b/gcc/optabs.def
> @@ -254,6 +254,7 @@ OPTAB_D (cond_fms_optab, "cond_fms$a")
>  OPTAB_D (cond_fnma_optab, "cond_fnma$a")
>  OPTAB_D (cond_fnms_optab, "cond_fnms$a")
>  OPTAB_D (cond_neg_optab, "cond_neg$a")
> +OPTAB_D (cond_one_cmpl_optab, "cond_one_cmpl$a")
>  OPTAB_D (cond_len_add_optab, "cond_len_add$a")
>  OPTAB_D (cond_len_sub_optab, "cond_len_sub$a")
>  OPTAB_D (cond_len_smul_optab, "cond_len_mul$a")
> @@ -278,6 +279,7 @@ OPTAB_D (cond_len_fms_optab, "cond_len_fms$a")
>  OPTAB_D (cond_len_fnma_optab, "cond_len_fnma$a")
>  OPTAB_D (cond_len_fnms_optab, "cond_len_fnms$a")
>  OPTAB_D (cond_len_neg_optab, "cond_len_neg$a")
> +OPTAB_D (cond_len_one_cmpl_optab, "cond_len_one_cmpl$a")
>  OPTAB_D (cmov_optab, "cmov$a6")
>  OPTAB_D (cstore_optab, "cstore$a4")
>  OPTAB_D (ctrap_optab, "ctrap$a4")
> diff --git a/gcc/testsuite/gcc.target/aarch64/sve/cond_unary_9.c b/gcc/testsuite/gcc.target/aarch64/sve/cond_unary_9.c
> new file mode 100644
> index 00000000000..d6bc0409630
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/sve/cond_unary_9.c
> @@ -0,0 +1,20 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -ftree-vectorize -moverride=sve_width=256 -fdump-tree-optimized" } */
> +
> +/* This is a reduced version of cond_unary_5.c */
> +
> +void __attribute__ ((noipa))
> +f (short *__restrict r,
> +   short *__restrict a,
> +   short *__restrict pred)
> +{
> +  for (int i = 0; i < 1024; ++i)
> +    r[i] = pred[i] != 0 ? ~(a[i]) : a[i];
> +}
> +
> +/* { dg-final { scan-assembler-times {\tnot\tz[0-9]+\.h, p[0-7]/m,} 1 } } */
> +
> +/* { dg-final { scan-assembler-not {\teor\tz} } } */
> +/* { dg-final { scan-assembler-not {\tmov\tz[0-9]+\.h, p[0-7]/m, #-1} } } */
> +
> +/* { dg-final { scan-tree-dump-times ".COND_NOT " 1 "optimized" } } */