diff options
author | Richard Sandiford <richard.sandiford@arm.com> | 2019-11-14 14:57:26 +0000 |
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committer | Richard Sandiford <rsandifo@gcc.gnu.org> | 2019-11-14 14:57:26 +0000 |
commit | 95da266b86fcdeff84fcadc5e3cde3d0027e571d (patch) | |
tree | 52b6e4dd3dd096c32a47a7e96a0b5cba544a6e74 /gcc/tree-vect-stmts.c | |
parent | 10116ec1c147a76522cafba6b6a5b4ed1cb37b77 (diff) |
Use build_vector_type_for_mode in get_vectype_for_scalar_type_and_size
Except for one case, get_vectype_for_scalar_type_and_size calculates
what the vector mode should be and then calls build_vector_type,
which recomputes the mode from scratch. This patch makes it use
build_vector_type_for_mode instead.
The exception mentioned above is when preferred_simd_mode returns
an integer mode, which it does if no appropriate vector mode exists.
The integer mode in question is usually word_mode, although epiphany
can return a doubleword mode in some cases.
There's no guarantee that this integer mode is appropriate, since for
example the scalar type could be a float. The traditional behaviour is
therefore to use the integer mode to determine a size only, and leave
mode_for_vector to pick the TYPE_MODE. (Note that it can actually end
up picking a vector mode if the target defines a disabled vector mode.
We therefore still need to check TYPE_MODE after building the type.)
2019-11-14 Richard Sandiford <richard.sandiford@arm.com>
gcc/
* tree-vect-stmts.c (get_vectype_for_scalar_type_and_size): If
targetm.vectorize.preferred_simd_mode returns an integer mode,
use mode_for_vector to decide what the vector type's mode
should actually be. Use build_vector_type_for_mode instead
of build_vector_type.
From-SVN: r278234
Diffstat (limited to 'gcc/tree-vect-stmts.c')
-rw-r--r-- | gcc/tree-vect-stmts.c | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/gcc/tree-vect-stmts.c b/gcc/tree-vect-stmts.c index 71c635c57b9..9361a23785e 100644 --- a/gcc/tree-vect-stmts.c +++ b/gcc/tree-vect-stmts.c @@ -11176,16 +11176,31 @@ get_vectype_for_scalar_type_and_size (tree scalar_type, poly_uint64 size) /* If no size was supplied use the mode the target prefers. Otherwise lookup a vector mode of the specified size. */ if (known_eq (size, 0U)) - simd_mode = targetm.vectorize.preferred_simd_mode (inner_mode); + { + simd_mode = targetm.vectorize.preferred_simd_mode (inner_mode); + if (SCALAR_INT_MODE_P (simd_mode)) + { + /* Traditional behavior is not to take the integer mode + literally, but simply to use it as a way of determining + the vector size. It is up to mode_for_vector to decide + what the TYPE_MODE should be. + + Note that nunits == 1 is allowed in order to support single + element vector types. */ + if (!multiple_p (GET_MODE_SIZE (simd_mode), nbytes, &nunits) + || !mode_for_vector (inner_mode, nunits).exists (&simd_mode)) + return NULL_TREE; + } + } else if (!multiple_p (size, nbytes, &nunits) || !mode_for_vector (inner_mode, nunits).exists (&simd_mode)) return NULL_TREE; - /* NOTE: nunits == 1 is allowed to support single element vector types. */ - if (!multiple_p (GET_MODE_SIZE (simd_mode), nbytes, &nunits)) - return NULL_TREE; - vectype = build_vector_type (scalar_type, nunits); + vectype = build_vector_type_for_mode (scalar_type, simd_mode); + /* In cases where the mode was chosen by mode_for_vector, check that + the target actually supports the chosen mode, or that it at least + allows the vector mode to be replaced by a like-sized integer. */ if (!VECTOR_MODE_P (TYPE_MODE (vectype)) && !INTEGRAL_MODE_P (TYPE_MODE (vectype))) return NULL_TREE; |