2 * Copyright (C) 1995-2011 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 * @brief lower mode_b operations to something the backend can handle
23 * @author Matthias Braun, Christoph Mallon
28 #include "lower_mode_b.h"
49 typedef struct needs_lowering_t {
54 static const lower_mode_b_config_t *config;
55 static needs_lowering_t *needs_lowering;
57 static ir_node *create_not(dbg_info *dbgi, ir_node *node)
59 ir_node *block = get_nodes_block(node);
60 ir_mode *mode = config->lowered_mode;
61 ir_tarval *tv_one = get_mode_one(mode);
62 ir_graph *irg = get_irn_irg(node);
63 ir_node *one = new_rd_Const(dbgi, irg, tv_one);
65 return new_rd_Eor(dbgi, block, node, one, mode);
68 static ir_node *convert_to_modeb(ir_node *node)
70 ir_node *block = get_nodes_block(node);
71 ir_graph *irg = get_irn_irg(node);
72 ir_mode *mode = config->lowered_mode;
73 ir_tarval *tv_zero = get_mode_null(mode);
74 ir_node *zero = new_r_Const(irg, tv_zero);
75 ir_node *cmp = new_r_Cmp(block, node, zero, ir_relation_less_greater);
79 ir_node *ir_create_cond_set(ir_node *cond_value, ir_mode *dest_mode)
81 ir_node *lower_block = part_block_edges(cond_value);
82 ir_node *upper_block = get_nodes_block(cond_value);
83 ir_graph *irg = get_irn_irg(cond_value);
84 ir_node *cond = new_r_Cond(upper_block, cond_value);
85 ir_node *proj_true = new_r_Proj(cond, mode_X, pn_Cond_true);
86 ir_node *proj_false = new_r_Proj(cond, mode_X, pn_Cond_false);
87 ir_node *in_true[1] = { proj_true };
88 ir_node *in_false[1] = { proj_false };
89 ir_node *true_block = new_r_Block(irg, ARRAY_SIZE(in_true), in_true);
90 ir_node *false_block = new_r_Block(irg, ARRAY_SIZE(in_false),in_false);
91 ir_node *true_jmp = new_r_Jmp(true_block);
92 ir_node *false_jmp = new_r_Jmp(false_block);
93 ir_node *lower_in[2] = { true_jmp, false_jmp };
94 ir_node *one = new_r_Const(irg, get_mode_one(dest_mode));
95 ir_node *zero = new_r_Const(irg, get_mode_null(dest_mode));
96 ir_node *phi_in[2] = { one, zero };
99 set_irn_in(lower_block, ARRAY_SIZE(lower_in), lower_in);
100 phi = new_r_Phi(lower_block, ARRAY_SIZE(phi_in), phi_in, dest_mode);
105 static ir_node *lower_node(ir_node *node)
107 dbg_info *dbgi = get_irn_dbg_info(node);
108 ir_node *block = get_nodes_block(node);
109 ir_mode *mode = config->lowered_mode;
110 ir_node *res = (ir_node*)get_irn_link(node);
116 node = skip_Tuple(node);
118 assert(get_irn_mode(node) == mode_b);
120 irg = get_irn_irg(node);
121 switch (get_irn_opcode(node)) {
128 arity = get_irn_arity(node);
129 in = ALLOCAN(ir_node*, arity);
130 dummy = new_r_Dummy(irg, mode);
131 for (i = 0; i < arity; ++i) {
134 new_phi = new_r_Phi(block, arity, in, mode);
135 /* FIXME This does not correctly break cycles: The Phi might not be the
136 * first in the recursion, so the caller(s) are some yet un-lowered
137 * nodes and this Phi might have them (indirectly) as operands, so they
138 * would be replaced twice. */
139 set_irn_link(node, new_phi);
141 for (i = 0; i < arity; ++i) {
142 ir_node *in = get_irn_n(node, i);
143 ir_node *lowered_in = lower_node(in);
145 set_irn_n(new_phi, i, lowered_in);
152 ir_node *lowered_left = lower_node(get_And_left(node));
153 ir_node *lowered_right = lower_node(get_And_right(node));
154 res = new_rd_And(dbgi, block, lowered_left, lowered_right, mode);
158 ir_node *lowered_left = lower_node(get_Or_left(node));
159 ir_node *lowered_right = lower_node(get_Or_right(node));
160 res = new_rd_Or(dbgi, block, lowered_left, lowered_right, mode);
164 ir_node *lowered_left = lower_node(get_Eor_left(node));
165 ir_node *lowered_right = lower_node(get_Eor_right(node));
166 res = new_rd_Eor(dbgi, block, lowered_left, lowered_right, mode);
171 ir_node *op = get_Not_op(node);
172 ir_node *low_op = lower_node(op);
174 res = create_not(dbgi, low_op);
179 ir_node *cond = get_Mux_sel(node);
180 ir_node *low_cond = lower_node(cond);
181 ir_node *v_true = get_Mux_true(node);
182 ir_node *low_v_true = lower_node(v_true);
183 ir_node *v_false = get_Mux_false(node);
184 ir_node *low_v_false = lower_node(v_false);
186 ir_node *and0 = new_rd_And(dbgi, block, low_cond, low_v_true, mode);
187 ir_node *not_cond = create_not(dbgi, low_cond);
188 ir_node *and1 = new_rd_And(dbgi, block, not_cond, low_v_false, mode);
189 res = new_rd_Or(dbgi, block, and0, and1, mode);
194 ir_node *left = get_Cmp_left(node);
195 ir_node *right = get_Cmp_right(node);
196 ir_mode *cmp_mode = get_irn_mode(left);
197 ir_relation relation = get_Cmp_relation(node);
199 if ((mode_is_int(cmp_mode) || mode_is_reference(cmp_mode)) &&
200 (get_mode_size_bits(cmp_mode) < get_mode_size_bits(mode) ||
201 (mode_is_signed(cmp_mode) && is_Const(right) && is_Const_null(right) && relation != ir_relation_greater))) {
209 if (relation == ir_relation_less) {
210 /* a < b -> (a - b) >> 31 */
213 } else if (relation == ir_relation_less_equal) {
214 /* a <= b -> ~(a - b) >> 31 */
218 } else if (relation == ir_relation_greater) {
219 /* a > b -> (b - a) >> 31 */
222 } else if (relation == ir_relation_greater_equal) {
223 /* a >= b -> ~(a - b) >> 31 */
231 bits = get_mode_size_bits(mode);
232 tv = new_tarval_from_long(bits-1, mode_Iu);
233 shift_cnt = new_rd_Const(dbgi, irg, tv);
235 if (cmp_mode != mode) {
236 a = new_rd_Conv(dbgi, block, a, mode);
237 b = new_rd_Conv(dbgi, block, b, mode);
240 res = new_rd_Sub(dbgi, block, a, b, mode);
242 res = new_rd_Not(dbgi, block, res, mode);
244 res = new_rd_Shr(dbgi, block, res, shift_cnt, mode);
246 /* synthesize the 0/1 value */
248 res = config->create_set(node);
254 ir_tarval *tv = get_Const_tarval(node);
255 if (tv == get_tarval_b_true()) {
256 ir_tarval *tv_one = get_mode_one(mode);
257 res = new_rd_Const(dbgi, irg, tv_one);
258 } else if (tv == get_tarval_b_false()) {
259 ir_tarval *tv_zero = get_mode_null(mode);
260 res = new_rd_Const(dbgi, irg, tv_zero);
262 panic("invalid boolean const %+F", node);
268 res = new_r_Unknown(irg, mode);
272 res = new_r_Bad(irg, mode);
276 panic("Don't know how to lower mode_b node %+F", node);
279 set_irn_link(node, res);
283 static bool needs_mode_b_input(const ir_node *node, int input)
285 return (is_Cond(node) && input == n_Cond_selector)
286 || (is_Mux(node) && input == n_Mux_sel);
290 * Collects "roots" of a mode_b calculation. These are nodes which require a
291 * mode_b input (Cond, Mux, Conv(xxx_b))
293 static void collect_needs_lowering(ir_node *node, void *env)
295 int arity = get_irn_arity(node);
299 /* if the node produces mode_b then it is a not a root (but should be
300 * something our lower_node function can handle) */
301 if (get_irn_mode(node) == mode_b) {
302 assert(is_And(node) || is_Or(node) || is_Eor(node) || is_Phi(node)
303 || is_Not(node) || is_Mux(node) || is_Cmp(node)
304 || is_Const(node) || is_Unknown(node) || is_Bad(node));
308 for (i = 0; i < arity; ++i) {
309 needs_lowering_t entry;
310 ir_node *in = get_irn_n(node, i);
311 if (get_irn_mode(in) != mode_b)
313 if (is_Cmp(in) && needs_mode_b_input(node, i))
318 ARR_APP1(needs_lowering_t, needs_lowering, entry);
322 void ir_lower_mode_b(ir_graph *irg, const lower_mode_b_config_t *nconfig)
329 /* edges are used by part_block_edges in the ir_create_cond_set variant. */
332 set_irg_state(irg, IR_GRAPH_STATE_MODEB_LOWERED);
333 ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK);
335 needs_lowering = NEW_ARR_F(needs_lowering_t, 0);
337 irg_walk_graph(irg, firm_clear_link, collect_needs_lowering, NULL);
339 n = ARR_LEN(needs_lowering);
340 for (i = 0; i < n; ++i) {
341 const needs_lowering_t *entry = &needs_lowering[i];
342 ir_node *node = entry->node;
343 int input = entry->input;
344 ir_node *in = get_irn_n(node, input);
345 ir_node *lowered = lower_node(in);
347 if (needs_mode_b_input(node, input))
348 lowered = convert_to_modeb(lowered);
349 set_irn_n(node, input, lowered);
352 ir_free_resources(irg, IR_RESOURCE_IRN_LINK);
354 DEL_ARR_F(needs_lowering);
357 /* lowering might create new blocks, so be sure to handle this */
358 clear_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_DOMINANCE
359 | IR_GRAPH_STATE_VALID_EXTENDED_BLOCKS);
360 edges_deactivate(irg);