search_type_for_mask uses a worklist to search a chain of boolean
operations for a natural vector mask type. This patch instead does
that in vect_determine_stmt_precisions, where we also look for
overpromoted integer operations. We then only need to compute
the precision once and can cache it in the stmt_vec_info.
The new function vect_determine_mask_precision is supposed
to handle exactly the same cases as search_type_for_mask_1,
and in the same way. There's a lot we could improve here,
but that's not stage 3 material.
I wondered about sharing mask_precision with other fields like
operation_precision, but in the end that seemed too dangerous.
We have patterns to convert between boolean and non-boolean
operations and it would be very easy to get mixed up about
which case the fields are describing.
2019-11-29 Richard Sandiford <richard.sandiford@arm.com>
gcc/
* tree-vectorizer.h (stmt_vec_info::mask_precision): New field.
(vect_use_mask_type_p): New function.
* tree-vect-patterns.c (vect_init_pattern_stmt): Copy the
mask precision to the pattern statement.
(append_pattern_def_seq): Add a scalar_type_for_mask parameter
and use it to initialize the new stmt's mask precision.
(search_type_for_mask_1): Delete.
(search_type_for_mask): Replace with...
(integer_type_for_mask): ...this new function. Use the information
cached in the stmt_vec_info.
(vect_recog_bool_pattern): Update accordingly.
(build_mask_conversion): Pass the scalar type associated with the
mask type to append_pattern_def_seq.
(vect_recog_mask_conversion_pattern): Likewise. Call
integer_type_for_mask instead of search_type_for_mask.
(vect_convert_mask_for_vectype): Call integer_type_for_mask instead
of search_type_for_mask.
(possible_vector_mask_operation_p): New function.
(vect_determine_mask_precision): Likewise.
(vect_determine_stmt_precisions): Call it.
From-SVN: r278850
