Richard Biener <[email protected]> writes:
> The following adds __attribute__((vector_mask)) to get access to
> the corresponding mask type for a vector type. The implementation
> simply uses truth_type_for so creating a mask type that's not
> what the target would choose as canonical, say a AVX2 style one
> when AVX512VL is enabled, is not possible. It might be possible
> to provide access to that with an optional argument specifying
> the precision of the bool element. The syntax is as simple as
>
> typedef vector_type mask_type __attribute__((vector_mask));
>
> In theory this allows to create unit testcases for vector
> lowering and ISEL.
>
> Bootstrapped and tested on x86_64-unknown-linux-gnu, I've also
> checked that it works with SVE and -msve-vector-bits=256 but
> I'm unsure how to build the vector type for a variable size case.
> Without -msve-vector-bits=256 the testcase is decomposed by
> vector lowering (I suppose there's no good way to "decompose"
> a fixed width vector to a variable length one without creating
> a loop around each stmt...).
>
> OK?
LGTM. As mentioned on IRC, it also seems to work for the
variable-length case. E.g. (names now meaningless):
typedef __SVInt8_t v8si;
typedef v8si v8sib __attribute__((vector_mask));
v8si __GIMPLE (ssa) foo (v8si v1, v8si v2, v8si v3, v8si v4)
{
v8sib tem;
v8si resr;
__BB(2):
tem_3 = v1_1(D) <= v2_2(D);
resr_4 = tem_3 ? v3_5(D) : v4_6(D);
return resr_4;
}
produces:
ptrue p0.b, all
cmple p0.b, p0/z, z0.b, z1.b
sel z0.b, p0, z2.b, z3.b
ret
Thanks,
Richard
>
> Thanks,
> Richard.
>
> 2022-02-11 Richard Biener <[email protected]>
>
> gcc/c-family/
> * c-attribs.cc (c_common_attribute_table): Add entry for
> vector_mask.
> (handle_vector_mask_attribute): New.
>
> gcc/c/
> * gimple-fe.cc (c_parser_gimple_statement): Properly parse
> VEC_COND_EXPRs.
>
> gcc/testsuite/
> * gcc.dg/gimplefe-48.c: New testcase.
> ---
> gcc/c-family/c-attribs.cc | 36 ++++++++++++++++++++++++++++++
> gcc/c/gimple-parser.cc | 12 ++++++----
> gcc/testsuite/gcc.dg/gimplefe-48.c | 19 ++++++++++++++++
> 3 files changed, 63 insertions(+), 4 deletions(-)
> create mode 100644 gcc/testsuite/gcc.dg/gimplefe-48.c
>
> diff --git a/gcc/c-family/c-attribs.cc b/gcc/c-family/c-attribs.cc
> index 4fb5dbd1409..3849dba90b2 100644
> --- a/gcc/c-family/c-attribs.cc
> +++ b/gcc/c-family/c-attribs.cc
> @@ -129,6 +129,8 @@ static tree handle_unavailable_attribute (tree *, tree,
> tree, int,
> bool *);
> static tree handle_vector_size_attribute (tree *, tree, tree, int,
> bool *) ATTRIBUTE_NONNULL(3);
> +static tree handle_vector_mask_attribute (tree *, tree, tree, int,
> + bool *) ATTRIBUTE_NONNULL(3);
> static tree handle_nonnull_attribute (tree *, tree, tree, int, bool *);
> static tree handle_nonstring_attribute (tree *, tree, tree, int, bool *);
> static tree handle_nothrow_attribute (tree *, tree, tree, int, bool *);
> @@ -417,6 +419,8 @@ const struct attribute_spec c_common_attribute_table[] =
> handle_unavailable_attribute, NULL },
> { "vector_size", 1, 1, false, true, false, true,
> handle_vector_size_attribute, NULL },
> + { "vector_mask", 0, 0, false, true, false, true,
> + handle_vector_mask_attribute, NULL },
> { "visibility", 1, 1, false, false, false, false,
> handle_visibility_attribute, NULL },
> { "tls_model", 1, 1, true, false, false, false,
> @@ -4419,6 +4423,38 @@ handle_vector_size_attribute (tree *node, tree name,
> tree args,
> return NULL_TREE;
> }
>
> +/* Handle a "vector_mask" attribute; arguments as in
> + struct attribute_spec.handler. */
> +
> +static tree
> +handle_vector_mask_attribute (tree *node, tree name, tree,
> + int ARG_UNUSED (flags),
> + bool *no_add_attrs)
> +{
> + *no_add_attrs = true;
> + if (!flag_gimple)
> + {
> + warning (OPT_Wattributes, "%qE attribute ignored", name);
> + return NULL_TREE;
> + }
> +
> + /* Determine the "base" type to apply the attribute to. */
> + tree type = type_for_vector_size (*node);
> + if (!VECTOR_TYPE_P (type) || VECTOR_BOOLEAN_TYPE_P (type))
> + {
> + warning (OPT_Wattributes, "%qE attribute only supported on "
> + "non-mask vector types", name);
> + return NULL_TREE;
> + }
> +
> + tree new_type = truth_type_for (type);
> +
> + /* Build back pointers if needed. */
> + *node = lang_hooks.types.reconstruct_complex_type (*node, new_type);
> +
> + return NULL_TREE;
> +}
> +
> /* Handle the "nonnull" attribute. */
>
> static tree
> diff --git a/gcc/c/gimple-parser.cc b/gcc/c/gimple-parser.cc
> index 51ddd86f23a..31075237c98 100644
> --- a/gcc/c/gimple-parser.cc
> +++ b/gcc/c/gimple-parser.cc
> @@ -860,9 +860,10 @@ c_parser_gimple_statement (gimple_parser &parser,
> gimple_seq *seq)
> if (lhs.value != error_mark_node
> && rhs.value != error_mark_node)
> {
> - /* If we parsed a comparison and the next token is a '?' then
> - parse a conditional expression. */
> - if (COMPARISON_CLASS_P (rhs.value)
> + /* If we parsed a comparison or an identifier and the next token
> + is a '?' then parse a conditional expression. */
> + if ((COMPARISON_CLASS_P (rhs.value)
> + || SSA_VAR_P (rhs.value))
> && c_parser_next_token_is (parser, CPP_QUERY))
> {
> struct c_expr trueval, falseval;
> @@ -874,7 +875,10 @@ c_parser_gimple_statement (gimple_parser &parser,
> gimple_seq *seq)
> if (trueval.value == error_mark_node
> || falseval.value == error_mark_node)
> return;
> - rhs.value = build3_loc (loc, COND_EXPR, TREE_TYPE (trueval.value),
> + rhs.value = build3_loc (loc,
> + VECTOR_TYPE_P (TREE_TYPE (rhs.value))
> + ? VEC_COND_EXPR : COND_EXPR,
> + TREE_TYPE (trueval.value),
> rhs.value, trueval.value, falseval.value);
> }
> if (get_gimple_rhs_class (TREE_CODE (rhs.value)) == GIMPLE_INVALID_RHS)
> diff --git a/gcc/testsuite/gcc.dg/gimplefe-48.c
> b/gcc/testsuite/gcc.dg/gimplefe-48.c
> new file mode 100644
> index 00000000000..13d534a40c1
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/gimplefe-48.c
> @@ -0,0 +1,19 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O -fgimple" } */
> +
> +typedef int v8si __attribute__((vector_size(8*sizeof(int))));
> +typedef v8si v8sib __attribute__((vector_mask));
> +
> +v8si res;
> +
> +void __GIMPLE (ssa) foo (v8si v1, v8si v2, v8si v3, v8si v4)
> +{
> + v8sib tem;
> + v8si resr;
> +
> +__BB(2):
> + tem_3 = v1_1(D) <= v2_2(D);
> + resr_4 = tem_3 ? v3_5(D) : v4_6(D);
> + res = resr_4;
> + return;
> +}
