tree.def (CASE_LABEL_EXPR): Fix documentation, mention all operands.

	* tree.def (CASE_LABEL_EXPR): Fix documentation, mention all operands.
	* tree-cfg.c (edge_to_cases): Fix documentation.

From-SVN: r186575

gcc/ChangeLog

+2012-04-18  Steven Bosscher  <steven@gcc.gnu.org>
+
+	* tree.def (CASE_LABEL_EXPR): Fix documentation, mention all operands.
+	* tree-cfg.c (edge_to_cases): Fix documentation.
+
 2012-04-18  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/alpha/sync.md (fetchop_name): Change ior attribute to "or".

gcc/tree-cfg.c

@@ -56,7 +56,7 @@ static const int initial_cfg_capacity = 20;
 
 /* This hash table allows us to efficiently lookup all CASE_LABEL_EXPRs
    which use a particular edge.  The CASE_LABEL_EXPRs are chained together
-   via their TREE_CHAIN field, which we clear after we're done with the
+   via their CASE_CHAIN field, which we clear after we're done with the
    hash table to prevent problems with duplication of GIMPLE_SWITCHes.
 
    Access to this list of CASE_LABEL_EXPRs allows us to efficiently

gcc/tree.def

@@ -876,10 +876,16 @@ DEFTREECODE (LOOP_EXPR, "loop_expr", tcc_statement, 1)
      of all the cases.  */
 DEFTREECODE (SWITCH_EXPR, "switch_expr", tcc_statement, 3)
 
-/* Used to represent a case label. The operands are CASE_LOW and
-   CASE_HIGH, respectively. If CASE_LOW is NULL_TREE, the label is a
-   'default' label. If CASE_HIGH is NULL_TREE, the label is a normal case
-   label.  CASE_LABEL is the corresponding LABEL_DECL.  */
+/* Used to represent a case label.
+
+   Operand 0 is CASE_LOW.  It may be NULL_TREE, in which case the label
+     is a 'default' label.
+   Operand 1 is CASE_HIGH.  If it is NULL_TREE, the label is a simple
+     (one-value) case label.  If it is non-NULL_TREE, the case is a range.
+   Operand 2 is CASE_LABEL, which is is the corresponding LABEL_DECL.
+   Operand 4 is CASE_CHAIN.  This operand is only used in tree-cfg.c to
+     speed up the lookup of case labels which use a particular edge in
+     the control flow graph.  */
 DEFTREECODE (CASE_LABEL_EXPR, "case_label_expr", tcc_statement, 4)
 
 /* Used to represent an inline assembly statement.  ASM_STRING returns a