diff mbox

[3/4] New attribute lookup function addition

Message ID 538829F6.1030108@suse.cz
State New
Headers show

Commit Message

Martin Liška May 30, 2014, 6:49 a.m. UTC 
Hi,
    this patch introduces a new function lookup_attribute_starting that can find all attributes starting with a specified string. Purpose of the function is to be able to identify e.g. if a function has any 'omp' attribute.

Bootstrapped and tested on x86_64-linux.
OK for trunk?

Thanks,
Martin

2014-05-29  Martin Liska  <mliska@suse.cz>

	* tree.h (private_lookup_attribute_starting): New function.
	(lookup_attribute_starting): Likewise.
	* tree.c (private_lookup_attribute_starting): Likewise.

Comments

Jeff Law May 30, 2014, 4:37 p.m. UTC | #1 
On 05/30/14 00:49, Martin Liška wrote:
> Hi,
>     this patch introduces a new function lookup_attribute_starting that
> can find all attributes starting with a specified string. Purpose of the
> function is to be able to identify e.g. if a function has any 'omp'
> attribute.
>
> Bootstrapped and tested on x86_64-linux.
> OK for trunk?
>
> Thanks,
> Martin
>
> 2014-05-29  Martin Liska  <mliska@suse.cz>
>
>      * tree.h (private_lookup_attribute_starting): New function.
>      (lookup_attribute_starting): Likewise.
>      * tree.c (private_lookup_attribute_starting): Likewise.
private_lookup_attribute_starting needs a block comment.

>
> +tree
> +private_lookup_attribute_starting (const char *attr_name, size_t
> attr_len, tree list)
Long line needs to be wrapped?   Please review the patch for lines that 
need wrapping at 80 columns.

So it's really a lookup by prefix, so I'd probably use a name like
lookup_attribute_by_prefix.  Why "private_" in the function name?


It appears it just returns the first attribute from LIST with the given 
prefix.  Presumably you use it iteratively.

> +/* Given an attribute name ATTR_NAME and a list of attributes LIST,
> +   return a pointer to the attribute's list element if the attribute
> +   starts with ATTR_NAME. ATTR_NAME must be in the form 'text' (not
> +   '__text__').  */
> +
> +static inline tree
> +lookup_attribute_starting (const char *attr_name, tree list)
> +{
> +  gcc_checking_assert (attr_name[0] != '_');
> +  /* In most cases, list is NULL_TREE.  */
> +  if (list == NULL_TREE)
> +    return NULL_TREE;
> +  else
> +    return private_lookup_attribute_starting (attr_name, strlen
> (attr_name), list);
> +}
So again, I prefer "prefix" rather than "starting".  Similarly this is 
meant to be called iteratively since you only get the first attribute 
with the given prefix, right?

OK with the nit fixes mentioned above.


Jeff
diff mbox

Patch

diff --git a/gcc/tree.c b/gcc/tree.c
index cf7e362..9c6b68c 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -5758,6 +5758,37 @@  private_lookup_attribute (const char *attr_name, size_t attr_len, tree list)
    return list;
  }
  
+tree
+private_lookup_attribute_starting (const char *attr_name, size_t attr_len, tree list)
+{
+  while (list)
+    {
+      size_t ident_len = IDENTIFIER_LENGTH (get_attribute_name (list));
+
+      if (attr_len > ident_len)
+	{
+	  list = TREE_CHAIN (list);
+	  continue;
+	}
+
+      const char *p = IDENTIFIER_POINTER (get_attribute_name (list));
+
+      if (strncmp (attr_name, p, attr_len) == 0)
+	break;
+
+      /* TODO: If we made sure that attributes were stored in the
+	 canonical form without '__...__' (ie, as in 'text' as opposed
+	 to '__text__') then we could avoid the following case.  */
+      if (p[0] == '_' && p[1] == '_' && strncmp (attr_name, p + 2, attr_len) == 0)
+	break;
+
+      list = TREE_CHAIN (list);
+    }
+
+  return list;
+}
+
+
  /* A variant of lookup_attribute() that can be used with an identifier
     as the first argument, and where the identifier can be either
     'text' or '__text__'.
diff --git a/gcc/tree.h b/gcc/tree.h
index 9fe7360..3e1b113 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -3731,6 +3731,10 @@  extern tree merge_type_attributes (tree, tree);
     and you should never call it directly.  */
  extern tree private_lookup_attribute (const char *, size_t, tree);
  
+/* This function is a private implementation detail
+   of lookup_attribute_starting() and you should never call it directly.  */
+extern tree private_lookup_attribute_starting (const char *, size_t, tree);
+
  /* Given an attribute name ATTR_NAME and a list of attributes LIST,
     return a pointer to the attribute's list element if the attribute
     is part of the list, or NULL_TREE if not found.  If the attribute
@@ -3753,6 +3757,23 @@  lookup_attribute (const char *attr_name, tree list)
      return private_lookup_attribute (attr_name, strlen (attr_name), list);
  }
  
+/* Given an attribute name ATTR_NAME and a list of attributes LIST,
+   return a pointer to the attribute's list element if the attribute
+   starts with ATTR_NAME. ATTR_NAME must be in the form 'text' (not
+   '__text__').  */
+
+static inline tree
+lookup_attribute_starting (const char *attr_name, tree list)
+{
+  gcc_checking_assert (attr_name[0] != '_');
+  /* In most cases, list is NULL_TREE.  */
+  if (list == NULL_TREE)
+    return NULL_TREE;
+  else
+    return private_lookup_attribute_starting (attr_name, strlen (attr_name), list);
+}
+
+
  /* This function is a private implementation detail of
     is_attribute_p() and you should never call it directly.  */
  extern bool private_is_attribute_p (const char *, size_t, const_tree);