2 * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * File name: ir/st/exc.c
23 * Purpose: Helper functions for jack exceptions.
24 * Author: Florian Liekweg
28 * Copyright: (c) 2002-2003 Universität Karlsruhe
35 Helper functions for exceptions
43 static char* exc_strings [] = {
44 "Invalid", /* invalid */
45 "Normal", /* normal */
46 "Entry", /* entry to region */
47 "Exit", /* exit of region */
48 "Handler", /* entry to handler */
54 Return true iff (block b is a handler entry AND a dominates b) OR
55 (b has a CFG successor that is both a handler entry AND is dominated
58 static bool has_handler (ir_graph *graph, ir_node *b, ir_node *a)
61 int n = get_irn_n_outs (b);
64 assert (0 && "Wrongly implemented");
65 /* must check for _immediate_ dominance !!! */
67 if (is_handler_entry (graph, b) && dominates (graph, a, b))
70 for (i = 0; i < n; i ++)
72 succ = get_irn_out (b, i);
74 if (has_handler (graph, succ, a))
82 Return true iff the given node represents an exception jump
84 static bool is_exc_jmp (ir_node *node)
86 ir_op *op = get_irn_op (node);
88 /* Proj_X (Load), Proj_X (Sto), Proj_X (Div_Int),
89 Proj_X (Raise), Proj_X (Call), Proj_X (Alloc) */
92 op = get_irn_op (get_Proj_pred (node));
94 assert ((is_fragile_op(get_Proj_pred(node))) &&
95 (op != op_Bad) /*&& (op != op_Unknown)*/ &&
96 (get_irn_mode(node) == mode_X));/* Check for proper Proj attr */
106 Return true iff the given node represents a normal cfg jump
109 static bool is_cfg_jmp (ir_node *node)
111 ir_op *op = get_irn_op (node);
115 op = get_irn_op (get_Proj_pred (node));
117 /* Proj_X (Proj_Cmp (Cond)) */
119 return (true); /* check for op == op_Cmp and op == op_Cond */
126 void set_Block_exc(ir_node *n, exc_t exc) {
129 exc_t get_Block_exc(ir_node *n) {
134 /* handler handling for Blocks */
136 set_Block_handler (ir_node *block, ir_node *handler) {
137 assert (is_Block(block));
138 assert (is_Block(handler));
142 get_Block_handler (ir_node *block) {
143 assert (is_Block(block));
147 /* handler handling for Nodes */
149 set_Node_handler (ir_node *node, ir_node *handler) {
154 get_Node_handler (ir_node *node) {
160 Return true iff a new exception region must be left upon entry of this block.
162 If all CFG preds of this block are exception jumps, then we must
165 bool is_handler_entry (ir_graph *graph, ir_node *block)
167 bool is_entry = true;
169 int n = get_irn_arity (block);
171 if (exc_invalid == get_Block_exc (block))
173 for (i = 0; (i < n) && (is_entry == true); i ++)
174 if (is_exc_jmp (get_irn_n (block, i)))
179 if (true == is_entry)
180 set_Block_exc (block, exc_handler);
183 return (exc_handler == get_Block_exc (block));
187 Return true iff a new exception region must be started upon entry of this block.
189 If this block immediately dominates a handler entry, we must return true.
191 bool is_region_entry (ir_graph *graph, ir_node *block)
193 assert (0 && "Not implemented");
195 if (exc_invalid == get_Block_exc (block))
198 int n = get_irn_n_outs (block);
201 bool no_handler = true;
203 for (i = 0; (i < n) && (no_handler == true); i ++)
205 succ = get_irn_out (block, i);
207 if (has_handler (graph, succ, block))
211 if (false == no_handler)
212 set_Block_exc (block, exc_region);
215 return (exc_region == get_Block_exc (block));
221 Return true iff this block is part of handler code.
223 If this block is dominated by a block for which {@link
224 is_handler_entry} is true, then this block is part of the handler.
226 bool is_handler_block (ir_graph *graph, ir_node *block)
228 assert (0 && "Not implemented");
230 if (exc_invalid == get_Block_exc (block))
232 bool no_handler = true;
233 dom_env_t *env = get_dom_env (graph, block);
234 int block_index = env->index_a;
235 bs_t block_mask = 0x00000001 << block_index;
236 int n_blocks = env->dt->n_blocks;
239 for (i = 0; (i < n_blocks) && (no_handler == true); i ++)
240 if (0 != (env->dt->masks [i] & block_mask)) /* if dominator */
241 if (is_handler_entry (graph, env->dt->blocks [i])) /* is handler entry */
244 delete_dom_env (env);
246 if (false == no_handler)
247 set_Block_exc (block, exc_handler);
250 return (exc_handler == get_Block_exc (block));
254 Convert a value of type exc_t to a descriptive string.
255 Returns a reference to a statically allocated, constant string.
258 const char *exc_to_string (exc_t exc)
260 int exc_val = (int) exc;
262 assert ((0 <= (int) exc_val) && (exc_val < (int) exc_max));
264 return (exc_strings [exc_val]);