+ * @page ir_graph The struct ir_graph
+ *
+ * This struct contains all information about a procedure.
+ * It's allocated directly to memory.
+ *
+ * The fields of ir_graph:
+ *
+ * *ent The entity describing this procedure.
+ *
+ * The beginning and end of a graph:
+ *
+ * *start_block This ir_node is the block that contains the unique
+ * start node of the procedure. With it it contains
+ * the Proj's on starts results.
+ * Further all Const nodes are placed in the start block.
+ * *start This ir_node is the unique start node of the procedure.
+ *
+ * *end_block This ir_node is the block that contains the unique
+ * end node of the procedure. This block contains no
+ * further nodes.
+ * *end This ir_node is the unique end node of the procedure.
+ *
+ * The following nodes are Projs from the start node, held in ir_graph for
+ * simple access:
+ *
+ * *frame The ir_node producing the pointer to the stack frame of
+ * the procedure as output. This is the Proj node on the
+ * third output of the start node. This output of the start
+ * node is tagged as pns_frame_base. In FIRM most local
+ * variables are modeled as data flow edges. Static
+ * allocated arrays can not be represented as data flow
+ * edges. Therefore FIRM has to represent them in the stack
+ * frame.
+ *
+ * *globals This models a pointer to a space in the memory where
+ * _all_ global things are held. Select from this pointer
+ * with a Sel node the pointer to a global variable /
+ * procedure / compiler known function... .
+ *
+ * *tls This models a pointer to a space in the memory where
+ * thread local things are held. Select from this pointer
+ * with a Sel node the pointer to a thread local variable.
+ *
+ * *args The ir_node that produces the arguments of the method as
+ * it's result. This is a Proj node on the fourth output of
+ * the start node. This output is tagged as pn_Start_T_args.
+ *
+ * *proj_args The proj nodes of the args node.
+ *
+ * *bad The Bad node is an auxiliary node. It is needed only once,
+ * so there is this globally reachable node.