Ilya Leoshkevich <i...@linux.ibm.com> writes:
> z13 supports only non-signaling vector comparisons. This means we
> cannot vectorize LT, LE, GT, GE and LTGT when compiling for z13.
> However, we cannot express this restriction today: the code only checks
> whether vcond$a$b optab exists, which does not contain information about
> the operation.
>
> Introduce a function that checks whether back-end supports vector
> comparisons with individual rtx codes by matching vcond expander's third
> argument with a fake comparison with the corresponding rtx code.
>
> gcc/ChangeLog:
>
> 2019-08-27 Ilya Leoshkevich <i...@linux.ibm.com>
>
> PR target/77918
> * optabs-tree.c (vcond_icode_p): New function.
> (vcond_eq_icode_p): New function.
> (expand_vec_cond_expr_p): Use vcond_icode_p and
> vcond_eq_icode_p.
> * optabs.c (can_vcond_compare_p): New function.
> (get_rtx_code): Use get_rtx_code_safe.
> (get_rtx_code_safe): New function.
> * optabs.h (can_vcond_compare_p): New function.
> (get_rtx_code_safe): Likewise.
> ---
> gcc/optabs-tree.c | 37 +++++++++++++++++++++++++++++++------
> gcc/optabs.c | 38 ++++++++++++++++++++++++++++++++++----
> gcc/optabs.h | 7 +++++++
> 3 files changed, 72 insertions(+), 10 deletions(-)
>
> diff --git a/gcc/optabs-tree.c b/gcc/optabs-tree.c
> index 8157798cc71..7f505c9cdee 100644
> --- a/gcc/optabs-tree.c
> +++ b/gcc/optabs-tree.c
> @@ -23,7 +23,10 @@ along with GCC; see the file COPYING3. If not see
> #include "coretypes.h"
> #include "target.h"
> #include "insn-codes.h"
> +#include "rtl.h"
> #include "tree.h"
> +#include "memmodel.h"
> +#include "optabs.h"
> #include "optabs-tree.h"
> #include "stor-layout.h"
>
> @@ -329,6 +332,28 @@ expand_vec_cmp_expr_p (tree value_type, tree mask_type,
> enum tree_code code)
> return false;
> }
>
> +/* Return true iff vcond_optab/vcondu_optab support the given tree
> + comparison. */
Realise it's a bit repetitive in the context of this patch, but...
/* Return true iff vcond_optab/vcondu_optab can handle a vector
comparison for code CODE, comparing operands of type CMP_OP_TYPE and
producing a result of type VALUE_TYPE. */
> +
> +static bool
> +vcond_icode_p (tree value_type, tree cmp_op_type, enum tree_code code)
> +{
> + return can_vcond_compare_p (get_rtx_code (code, TYPE_UNSIGNED
> (cmp_op_type)),
> + TYPE_MODE (value_type), TYPE_MODE (cmp_op_type));
> +}
> +
> +/* Return true iff vcondeq_optab supports the given tree comparison. */
Same idea here.
> +
> +static bool
> +vcond_eq_icode_p (tree value_type, tree cmp_op_type, enum tree_code code)
> +{
> + if (code != EQ_EXPR && code != NE_EXPR)
> + return false;
> +
> + return get_vcond_eq_icode (TYPE_MODE (value_type), TYPE_MODE (cmp_op_type))
> + != CODE_FOR_nothing;
> +}
> +
> /* Return TRUE iff, appropriate vector insns are available
> for vector cond expr with vector type VALUE_TYPE and a comparison
> with operand vector types in CMP_OP_TYPE. */
> @@ -347,14 +372,14 @@ expand_vec_cond_expr_p (tree value_type, tree
> cmp_op_type, enum tree_code code)
> || maybe_ne (GET_MODE_NUNITS (value_mode), GET_MODE_NUNITS
> (cmp_op_mode)))
> return false;
>
> - if (get_vcond_icode (TYPE_MODE (value_type), TYPE_MODE (cmp_op_type),
> - TYPE_UNSIGNED (cmp_op_type)) == CODE_FOR_nothing
> - && ((code != EQ_EXPR && code != NE_EXPR)
> - || get_vcond_eq_icode (TYPE_MODE (value_type),
> - TYPE_MODE (cmp_op_type)) == CODE_FOR_nothing))
> + if (get_rtx_code_safe (code, TYPE_UNSIGNED (cmp_op_type))
> + == LAST_AND_UNUSED_RTX_CODE)
> + /* This may happen, for example, if code == SSA_NAME, in which case we
> + cannot be certain whether a vector insn is available. */
> return false;
I think this should just be:
if (TREE_CODE_CLASS (tcode) != tcc_comparison)
return false;
OK with those changes and without the introduction of get_rtx_code_safe.
Thanks,
Richard
