Hello,
On 14 Oct 13:40, Joseph Myers wrote:
> On Wed, 14 Oct 2015, Kirill Yukhin wrote:
>
> > Is it ok for trunk?
>
> This patch has no documentation. Documentation for new attributes must be
> added to extend.texi.
Fixed. Extra entry to gcc/Changelog:
* doc/extend.texi (simd): Document new attribute.
> > Enables creation of one or more versions that can process multiple
> > arguments using SIMD instructions from a single invocation from a SIMD
> > loop. It is ultimately an alias to `omp declare simd’ pragma, available
> > w/o additional compiler switches. It is prohibited to use the attribute
> > along with Cilk Plus’s `vector’ attribute. If the attribute is specified
> > and `pragma omp declare simd’ presents on a decl, then the attribute is
> > ignored.
>
> This is missing the key information that it's not just about *creation* of
> the versions, it's about (in the case of an external declaration)
> *assuming* such versions were created in another translation unit. And
> you should have a link to the external ABI documents specifying for each
> architecture for which this involves such an assumption exactly what
> versions may be assumed to be present - this is what's required to be able
> to use the attribute in headers for a library and know that future GCC
> versions won't reinterpret the attribute as implying some versions for
> future ISA extensions are also present.
I've put reference to x86_64 Vector ABI in the attribute documentation.
> I wonder whether the syntax for this attribute should allow optional
> arguments to describe what versions are present, but maybe that can be
> deferred until e.g. you want a way in future for a library to specify it
> has an AVX1024 version of a function as well as the baseline ABI set of
> versions.
We'll add it later when needed.
> Joseph S. Myers
> jos...@codesourcery.com
--
Thanks, K
diff --git a/gcc/c/c-parser.c b/gcc/c/c-parser.c
index 2d24c21..b83c9d8 100644
--- a/gcc/c/c-parser.c
+++ b/gcc/c/c-parser.c
@@ -224,6 +224,9 @@ struct GTY(()) c_parser {
/* Buffer to hold all the tokens from parsing the vector attribute for the
SIMD-enabled functions (formerly known as elemental functions). */
vec <c_token, va_gc> *cilk_simd_fn_tokens;
+
+ /* Designates if "simd" attribute is specified in decl. */
+ BOOL_BITFIELD simd_attr_present : 1;
};
@@ -1700,7 +1703,8 @@ c_parser_declaration_or_fndef (c_parser *parser, bool
fndef_ok,
if (declarator == NULL)
{
if (omp_declare_simd_clauses.exists ()
- || !vec_safe_is_empty (parser->cilk_simd_fn_tokens))
+ || !vec_safe_is_empty (parser->cilk_simd_fn_tokens)
+ || parser->simd_attr_present)
c_finish_omp_declare_simd (parser, NULL_TREE, NULL_TREE,
omp_declare_simd_clauses);
c_parser_skip_to_end_of_block_or_statement (parser);
@@ -1796,7 +1800,8 @@ c_parser_declaration_or_fndef (c_parser *parser, bool
fndef_ok,
if (!d)
d = error_mark_node;
if (omp_declare_simd_clauses.exists ()
- || !vec_safe_is_empty (parser->cilk_simd_fn_tokens))
+ || !vec_safe_is_empty (parser->cilk_simd_fn_tokens)
+ || parser->simd_attr_present)
c_finish_omp_declare_simd (parser, d, NULL_TREE,
omp_declare_simd_clauses);
}
@@ -1809,7 +1814,8 @@ c_parser_declaration_or_fndef (c_parser *parser, bool
fndef_ok,
if (!d)
d = error_mark_node;
if (omp_declare_simd_clauses.exists ()
- || !vec_safe_is_empty (parser->cilk_simd_fn_tokens))
+ || !vec_safe_is_empty (parser->cilk_simd_fn_tokens)
+ || parser->simd_attr_present)
c_finish_omp_declare_simd (parser, d, NULL_TREE,
omp_declare_simd_clauses);
start_init (d, asm_name, global_bindings_p ());
@@ -1838,7 +1844,8 @@ c_parser_declaration_or_fndef (c_parser *parser, bool
fndef_ok,
chainon (postfix_attrs,
all_prefix_attrs));
if (omp_declare_simd_clauses.exists ()
- || !vec_safe_is_empty (parser->cilk_simd_fn_tokens))
+ || !vec_safe_is_empty (parser->cilk_simd_fn_tokens)
+ || parser->simd_attr_present)
{
tree parms = NULL_TREE;
if (d && TREE_CODE (d) == FUNCTION_DECL)
@@ -1967,7 +1974,8 @@ c_parser_declaration_or_fndef (c_parser *parser, bool
fndef_ok,
true, false, NULL, vNULL);
store_parm_decls ();
if (omp_declare_simd_clauses.exists ()
- || !vec_safe_is_empty (parser->cilk_simd_fn_tokens))
+ || !vec_safe_is_empty (parser->cilk_simd_fn_tokens)
+ || parser->simd_attr_present)
c_finish_omp_declare_simd (parser, current_function_decl, NULL_TREE,
omp_declare_simd_clauses);
DECL_STRUCT_FUNCTION (current_function_decl)->function_start_locus
@@ -3998,6 +4006,12 @@ c_parser_attributes (c_parser *parser)
c_parser_cilk_simd_fn_vector_attrs (parser, *v_token);
continue;
}
+ if (is_attribute_p ("simd", attr_name))
+ {
+ parser->simd_attr_present = 1;
+ c_parser_consume_token (parser);
+ continue;
+ }
c_parser_consume_token (parser);
if (c_parser_next_token_is_not (parser, CPP_OPEN_PAREN))
{
@@ -14210,9 +14224,10 @@ c_finish_omp_declare_simd (c_parser *parser, tree
fndecl, tree parms,
vec<c_token> clauses)
{
if (flag_cilkplus
- && clauses.exists () && !vec_safe_is_empty (parser->cilk_simd_fn_tokens))
+ && (clauses.exists () || parser->simd_attr_present)
+ && !vec_safe_is_empty (parser->cilk_simd_fn_tokens))
{
- error ("%<#pragma omp declare simd%> cannot be used in the same "
+ error ("%<#pragma omp declare simd%> or __simd__ attribute cannot be
used in the same "
"function marked as a Cilk Plus SIMD-enabled function");
vec_free (parser->cilk_simd_fn_tokens);
return;
@@ -14245,7 +14260,7 @@ c_finish_omp_declare_simd (c_parser *parser, tree
fndecl, tree parms,
unsigned int tokens_avail = parser->tokens_avail;
gcc_assert (parser->tokens == &parser->tokens_buf[0]);
bool is_cilkplus_cilk_simd_fn = false;
-
+
if (flag_cilkplus && !vec_safe_is_empty (parser->cilk_simd_fn_tokens))
{
parser->tokens = parser->cilk_simd_fn_tokens->address ();
@@ -14257,41 +14272,63 @@ c_finish_omp_declare_simd (c_parser *parser, tree
fndecl, tree parms,
parser->tokens = clauses.address ();
parser->tokens_avail = clauses.length ();
}
-
- /* c_parser_omp_declare_simd pushed 2 extra CPP_EOF tokens at the end. */
- while (parser->tokens_avail > 3)
+
+ if (parser->simd_attr_present
+ && is_cilkplus_cilk_simd_fn)
{
- c_token *token = c_parser_peek_token (parser);
- if (!is_cilkplus_cilk_simd_fn)
- gcc_assert (token->type == CPP_NAME
- && strcmp (IDENTIFIER_POINTER (token->value), "simd") == 0);
- else
- gcc_assert (token->type == CPP_NAME
- && is_cilkplus_vector_p (token->value));
- c_parser_consume_token (parser);
- parser->in_pragma = true;
+ error ("SIMD-enabled function attributes"
+ "are allowed when attribute __simd__ is specified");
+ clauses[0].type = CPP_EOF;
+ return;
+ }
+ /* Attach `omp declare simd’ attribute if __simd__ is specified AND no
OpenMP clauses
+ present in decl. */
+ if (parser->simd_attr_present
+ && parser->tokens_avail == 0)
+ {
tree c = NULL_TREE;
- if (is_cilkplus_cilk_simd_fn)
- c = c_parser_omp_all_clauses (parser, CILK_SIMD_FN_CLAUSE_MASK,
- "SIMD-enabled functions attribute");
- else
- c = c_parser_omp_all_clauses (parser, OMP_DECLARE_SIMD_CLAUSE_MASK,
- "#pragma omp declare simd");
- c = c_omp_declare_simd_clauses_to_numbers (parms, c);
- if (c != NULL_TREE)
- c = tree_cons (NULL_TREE, c, NULL_TREE);
- if (is_cilkplus_cilk_simd_fn)
- {
- tree k = build_tree_list (get_identifier ("cilk simd function"),
- NULL_TREE);
- TREE_CHAIN (k) = DECL_ATTRIBUTES (fndecl);
- DECL_ATTRIBUTES (fndecl) = k;
- }
c = build_tree_list (get_identifier ("omp declare simd"), c);
TREE_CHAIN (c) = DECL_ATTRIBUTES (fndecl);
DECL_ATTRIBUTES (fndecl) = c;
}
+ else
+ {
+ /* c_parser_omp_declare_simd pushed 2 extra CPP_EOF tokens at the end.
*/
+ while (parser->tokens_avail > 3)
+ {
+ c_token *token = c_parser_peek_token (parser);
+ if (!is_cilkplus_cilk_simd_fn)
+ gcc_assert (token->type == CPP_NAME
+ && strcmp (IDENTIFIER_POINTER (token->value), "simd")
== 0);
+ else
+ gcc_assert (token->type == CPP_NAME
+ && is_cilkplus_vector_p (token->value));
+ c_parser_consume_token (parser);
+ parser->in_pragma = true;
+
+ tree c = NULL_TREE;
+ if (is_cilkplus_cilk_simd_fn)
+ c = c_parser_omp_all_clauses (parser, CILK_SIMD_FN_CLAUSE_MASK,
+ "SIMD-enabled functions attribute");
+ else
+ c = c_parser_omp_all_clauses (parser, OMP_DECLARE_SIMD_CLAUSE_MASK,
+ "#pragma omp declare simd");
+ c = c_omp_declare_simd_clauses_to_numbers (parms, c);
+ if (c != NULL_TREE)
+ c = tree_cons (NULL_TREE, c, NULL_TREE);
+ if (is_cilkplus_cilk_simd_fn)
+ {
+ tree k = build_tree_list (get_identifier ("cilk simd function"),
+ NULL_TREE);
+ TREE_CHAIN (k) = DECL_ATTRIBUTES (fndecl);
+ DECL_ATTRIBUTES (fndecl) = k;
+ }
+ c = build_tree_list (get_identifier ("omp declare simd"), c);
+ TREE_CHAIN (c) = DECL_ATTRIBUTES (fndecl);
+ DECL_ATTRIBUTES (fndecl) = c;
+ }
+ }
parser->tokens = &parser->tokens_buf[0];
parser->tokens_avail = tokens_avail;
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index 79440d3..6296a80 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -3066,6 +3066,20 @@ This function attribute make a stack protection of the
function if
flags @option{fstack-protector} or @option{fstack-protector-strong}
or @option{fstack-protector-explicit} are set.
+@item simd
+@cindex @code{simd} function attribute.
+This attribute enables creation of one or more function versions that
+can process multiple arguments using SIMD instructions from a
+single invocation. Specifying this attribute allows compiler to
+assume that such a versions are available at link time (provided
+in the same or another translation unit). Generated versions are
+target dependent and described in corresponding Vector ABI document. For
+x86_64 target this document can be found
+@w{@uref{https://sourceware.org/glibc/wiki/libmvec?action=AttachFile&do=view&target=VectorABI.txt,here}}.
+It is prohibited to use the attribute along with Cilk Plus's @code{vector}
+attribute. If the attribute is specified and @code{#pragma omp declare simd}
+presented on a declaration, then the attribute is ignored.
+
@item target (@var{options})
@cindex @code{target} function attribute
Multiple target back ends implement the @code{target} attribute
diff --git a/gcc/omp-low.c b/gcc/omp-low.c
index cdcf9d6..87537cd 100644
--- a/gcc/omp-low.c
+++ b/gcc/omp-low.c
@@ -13919,10 +13919,7 @@ public:
bool
pass_omp_simd_clone::gate (function *)
{
- return ((flag_openmp || flag_openmp_simd
- || flag_cilkplus
- || (in_lto_p && !flag_wpa))
- && (targetm.simd_clone.compute_vecsize_and_simdlen != NULL));
+ return targetm.simd_clone.compute_vecsize_and_simdlen != NULL;
}
} // anon namespace
diff --git a/gcc/testsuite/c-c++-common/attr-simd-2.c
b/gcc/testsuite/c-c++-common/attr-simd-2.c
new file mode 100644
index 0000000..263fa9a
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/attr-simd-2.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "-fdump-tree-optimized -fopenmp-simd" } */
+
+#pragma omp declare simd
+__attribute__((__simd__))
+static int simd_attr (void)
+{
+ return 0;
+}
+
+/* { dg-final { scan-tree-dump "simdclone" "optimized" } } */
diff --git a/gcc/testsuite/c-c++-common/attr-simd-3.c
b/gcc/testsuite/c-c++-common/attr-simd-3.c
new file mode 100644
index 0000000..2bbdf04
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/attr-simd-3.c
@@ -0,0 +1,5 @@
+/* { dg-do compile } */
+/* { dg-options "-fcilkplus" } */
+/* { dg-prune-output "undeclared here \\(not in a function\\)|\[^\n\r\]* was
not declared in this scope" } */
+
+void f () __attribute__((__simd__, __vector__)); /* { dg-error "in the same
function marked as a Cilk Plus" } */
diff --git a/gcc/testsuite/c-c++-common/attr-simd.c
b/gcc/testsuite/c-c++-common/attr-simd.c
new file mode 100644
index 0000000..5dad89c
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/attr-simd.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { dg-options "-fdump-tree-optimized" } */
+
+__attribute__((__simd__))
+static int simd_attr (void)
+{
+ return 0;
+}
+
+/* { dg-final { scan-tree-dump "simdclone" "optimized" } } */
