jit: document union types

gcc/jit/ChangeLog:
	* docs/topics/types.rst (gcc_jit_context_new_union_type): Add
	documentation.
	* docs/_build/texinfo/libgccjit.texi: Regenerate.

gcc/testsuite/ChangeLog:
	* jit.dg/test-accessing-union.c: Add comments for use by
	gcc/jit/docs/topics/types.rst.

From-SVN: r225246

gcc/jit/ChangeLog

 2015-07-01  David Malcolm  <dmalcolm@redhat.com>
 
+	* docs/topics/types.rst (gcc_jit_context_new_union_type): Add
+	documentation.
+	* docs/_build/texinfo/libgccjit.texi: Regenerate.
+
+2015-07-01  David Malcolm  <dmalcolm@redhat.com>
+
 	* docs/topics/contexts.rst (gcc_jit_context_set_bool_option):
 	Clarify lack of lifetime requirements on (const char *) parameter.
 	* docs/topics/expressions.rst

gcc/jit/docs/topics/types.rst

@@ -230,3 +230,22 @@ You can model C `struct` types by creating :c:type:`gcc_jit_struct *` and
    Populate the fields of a formerly-opaque struct type.
 
    This can only be called once on a given struct type.
+
+.. function:: gcc_jit_type *\
+              gcc_jit_context_new_union_type (gcc_jit_context *ctxt,\
+                                              gcc_jit_location *loc,\
+                                              const char *name,\
+                                              int num_fields,\
+                                              gcc_jit_field **fields)
+
+     Construct a new union type, with the given name and fields.
+
+     The parameter ``name`` must be non-NULL.  It is copied, so the input
+     buffer does not need to outlive the call.
+
+     Example of use:
+
+     .. literalinclude:: ../../../testsuite/jit.dg/test-accessing-union.c
+       :start-after: /* Quote from here in docs/topics/types.rst.  */
+       :end-before: /* Quote up to here in docs/topics/types.rst.  */
+       :language: c

gcc/testsuite/ChangeLog

+2015-07-01  David Malcolm  <dmalcolm@redhat.com>
+
+	* jit.dg/test-accessing-union.c: Add comments for use by
+	gcc/jit/docs/topics/types.rst.
+
 2015-07-01  Matthew Wahab  <matthew.wahab@arm.com>
 
 	* gcc.target/arm/armv8-sync-comp-swap.c: Replace

gcc/testsuite/jit.dg/test-accessing-union.c

@@ -5,6 +5,8 @@
 
 #include "harness.h"
 
+/* Quote from here in docs/topics/types.rst.  */
+
 union int_or_float
 {
   int as_int;
@@ -77,6 +79,8 @@ create_code (gcc_jit_context *ctxt, void *user_data)
 				 as_float));
 }
 
+/* Quote up to here in docs/topics/types.rst.  */
+
 void
 verify_code (gcc_jit_context *ctxt, gcc_jit_result *result)
 {