nsz Git - libfirm/blob - ir/lower/lower_mode_b.c

   1 /*
   2  * Copyright (C) 1995-2007 University of Karlsruhe.  All right reserved.
   3  *
   4  * This file is part of libFirm.
   5  *
   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.
  10  *
  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.
  14  *
  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
  17  * PURPOSE.
  18  */
  19
  20 /**
  21  * @file
  22  * @author      Matthias Braun, Christoph Mallon
  23  * @version     $Id$
  24  */
  25 #ifdef HAVE_CONFIG_H
  26 #include "config.h"
  27 #endif
  28
  29 #include <stdlib.h>
  30
  31 #include "irnode_t.h"
  32 #include "ircons_t.h"
  33 #include "irgwalk.h"
  34 #include "irtools.h"
  35 #include "tv.h"
  36 #include "error.h"
  37 #include "lowering.h"
  38
  39 static ir_mode *lowered_mode     = NULL;
  40 static int      lower_direct_cmp = 0;
  41 static ir_type *lowered_type     = NULL;
  42
  43 static ir_node *create_not(dbg_info *dbgi, ir_node *node)
  44 {
  45         ir_graph *irg    = current_ir_graph;
  46         ir_node  *block  = get_nodes_block(node);
  47         tarval   *tv_one = get_tarval_one(lowered_mode);
  48         ir_node  *one    = new_d_Const(dbgi, lowered_mode, tv_one);
  49
  50         return new_rd_Eor(dbgi, irg, block, node, one, lowered_mode);
  51 }
  52
  53 static ir_node *create_convb(ir_node *node)
  54 {
  55         ir_graph *irg   = current_ir_graph;
  56         ir_node  *block = get_nodes_block(node);
  57         ir_node  *conv  = new_rd_Conv(NULL, irg, block, node, mode_b);
  58
  59         return conv;
  60 }
  61
  62 static ir_type *create_lowered_type(void)
  63 {
  64         if(lowered_type == NULL) {
  65                 lowered_type = new_type_primitive(new_id_from_str("__lowered_mode_b"),
  66                                                   lowered_mode);
  67         }
  68         return lowered_type;
  69 }
  70
  71 static void adjust_method_type(ir_type *method_type)
  72 {
  73         int i;
  74         int n_params;
  75         int n_res;
  76
  77         n_params = get_method_n_params(method_type);
  78         for(i = 0; i < n_params; ++i) {
  79                 ir_type *param = get_method_param_type(method_type, i);
  80                 if(get_type_mode(param) == mode_b) {
  81                         set_method_param_type(method_type, i, create_lowered_type());
  82                 }
  83         }
  84
  85         n_res = get_method_n_ress(method_type);
  86         for(i = 0; i < n_res; ++i) {
  87                 ir_type *res_type = get_method_res_type(method_type, i);
  88                 if(get_type_mode(res_type) == mode_b) {
  89                         set_method_res_type(method_type, i, create_lowered_type());
  90                 }
  91         }
  92 }
  93
  94 static ir_node *lower_node(ir_node *node)
  95 {
  96         ir_graph *irg   = current_ir_graph;
  97         dbg_info *dbgi  = get_irn_dbg_info(node);
  98         ir_op    *op    = get_irn_op(node);
  99         ir_node  *block = get_nodes_block(node);
 100         ir_node  *res;
 101
 102         assert(get_irn_mode(node) == mode_b);
 103
 104         res = get_irn_link(node);
 105         if(res != NULL)
 106                 return res;
 107
 108         /* TODO: be robust against phi-loops... */
 109         if(op == op_Phi) {
 110                 int       i, arity;
 111                 ir_node **in;
 112                 ir_node  *unknown, *new_phi;
 113
 114                 arity = get_irn_arity(node);
 115                 in    = alloca(arity * sizeof(in[0]));
 116                 unknown = new_Unknown(lowered_mode);
 117                 for(i = 0; i < arity; ++i) {
 118                         in[i] = unknown;
 119                 }
 120                 new_phi = new_rd_Phi(dbgi, irg, block, arity, in,
 121                                               lowered_mode);
 122                 set_irn_link(node, new_phi);
 123
 124                 for(i = 0; i < arity; ++i) {
 125                         ir_node *in     = get_irn_n(node, i);
 126                         ir_node *low_in = lower_node(in);
 127
 128                         set_irn_n(new_phi, i, low_in);
 129                 }
 130
 131                 return new_phi;
 132         }
 133
 134         if(op == op_And || op == op_Or || op == op_Eor) {
 135                 int i, arity;
 136                 ir_node *copy = exact_copy(node);
 137
 138                 arity = get_irn_arity(node);
 139                 for(i = 0; i < arity; ++i) {
 140                         ir_node *in     = get_irn_n(node, i);
 141                         ir_node *low_in = lower_node(in);
 142
 143                         set_irn_n(copy, i, low_in);
 144                 }
 145                 set_irn_mode(copy, lowered_mode);
 146
 147                 set_irn_link(node, copy);
 148                 return copy;
 149         }
 150         if(op == op_Not) {
 151                 ir_node *op     = get_Not_op(node);
 152                 ir_node *low_op = lower_node(op);
 153
 154                 res = create_not(dbgi, low_op);
 155                 set_irn_link(node, res);
 156                 return res;
 157         }
 158         if(op == op_Psi) {
 159                 ir_node *cond        = get_Psi_cond(node, 0);
 160                 ir_node *low_cond    = lower_node(cond);
 161                 ir_node *v_true      = get_Psi_val(node, 0);
 162                 ir_node *low_v_true  = lower_node(v_true);
 163                 ir_node *v_false     = get_Psi_default(node);
 164                 ir_node *low_v_false = lower_node(v_false);
 165
 166                 ir_node *and0     = new_rd_And(dbgi, irg, block, low_cond, low_v_true,
 167                                                lowered_mode);
 168
 169                 ir_node *not_cond = create_not(dbgi, low_cond);
 170
 171                 ir_node *and1     = new_rd_And(dbgi, irg, block, not_cond, low_v_false,
 172                                                lowered_mode);
 173
 174                 ir_node *or       = new_rd_Or(dbgi, irg, block, and0, and1,
 175                                               lowered_mode);
 176
 177                 set_irn_link(node, or);
 178                 return or;
 179         }
 180         if(op == op_Conv) {
 181                 tarval  *tv_one   = get_tarval_one(lowered_mode);
 182                 ir_node *one      = new_d_Const(dbgi, lowered_mode, tv_one);
 183                 tarval  *tv_zero  = get_tarval_null(lowered_mode);
 184                 ir_node *zero     = new_d_Const(dbgi, lowered_mode, tv_zero);
 185                 ir_node *pred     = get_Conv_op(node);
 186                 ir_mode *mode     = get_irn_mode(pred);
 187                 tarval  *tv_zeroc = get_tarval_null(mode);
 188                 ir_node *zero_cmp = new_d_Const(dbgi, mode, tv_zeroc);
 189
 190                 ir_node *cmp      = new_rd_Cmp(dbgi, irg, block, pred, zero_cmp);
 191                 ir_node *proj     = new_rd_Proj(dbgi, irg, block, cmp, mode_b,
 192                                                 pn_Cmp_Lg);
 193                 ir_node *vals[2]  = { one, zero };
 194                 ir_node *psi      = new_rd_Psi(dbgi, irg, block, 1, &proj, vals,
 195                                                lowered_mode);
 196
 197                 set_irn_link(node, psi);
 198                 return psi;
 199         }
 200         if(op == op_Proj) {
 201                 ir_node *pred = get_Proj_pred(node);
 202
 203                 if(is_Cmp(pred)) {
 204                         ir_node *left  = get_Cmp_left(pred);
 205                         ir_node *right = get_Cmp_right(pred);
 206                         ir_mode *mode  = get_irn_mode(left);
 207
 208                         if ((mode_is_int(mode) || mode_is_reference(mode)) && (
 209                                                 get_mode_size_bits(mode) < get_mode_size_bits(lowered_mode) ||
 210                                                 (is_Const(right) && is_Const_null(right))
 211                                         )) {
 212                                 int      pnc      = get_Proj_proj(node);
 213                                 int      need_not = 0;
 214                                 ir_node *a        = NULL;
 215                                 ir_node *b        = NULL;
 216
 217                                 if(pnc == pn_Cmp_Lt) {
 218                                         /* a < b  ->  (a - b) >> 31 */
 219                                         a = left;
 220                                         b = right;
 221                                 } else if(pnc == pn_Cmp_Le) {
 222                                         /* a <= b  -> ((a - b) >> 31) ^ 1 */
 223                                         a        = right;
 224                                         b        = left;
 225                                         need_not = 1;
 226                                 } else if(pnc == pn_Cmp_Gt) {
 227                                         /* a > b   -> (b - a) >> 31 */
 228                                         a = right;
 229                                         b = left;
 230                                 } else if(pnc == pn_Cmp_Ge) {
 231                                         /* a >= b   -> ((a - b) >> 31) ^ 1 */
 232                                         a        = left;
 233                                         b        = right;
 234                                         need_not = 1;
 235                                 }
 236
 237                                 if(a != NULL) {
 238                                         tarval  *tv        = new_tarval_from_long(31, mode_Iu);
 239                                         ir_node *shift_cnt = new_d_Const(dbgi, mode_Iu, tv);
 240
 241                                         if(mode != lowered_mode) {
 242                                                 a = new_rd_Conv(dbgi, irg, block, a, lowered_mode);
 243                                                 b = new_rd_Conv(dbgi, irg, block, b, lowered_mode);
 244                                         }
 245
 246                                         res = new_rd_Sub(dbgi, irg, block, a, b, lowered_mode);
 247                                         res = new_rd_Shr(dbgi, irg, block, res, shift_cnt,
 248                                                          lowered_mode);
 249
 250                                         if(need_not) {
 251                                                 res = create_not(dbgi, res);
 252                                         }
 253                                         set_irn_link(node, res);
 254                                         return res;
 255                                 }
 256                         }
 257
 258                         {
 259                         /* synthesize the 0/1 value */
 260                         tarval  *tv_one  = get_tarval_one(lowered_mode);
 261                         ir_node *one     = new_d_Const(dbgi, lowered_mode, tv_one);
 262                         tarval  *tv_zero = get_tarval_null(lowered_mode);
 263                         ir_node *zero    = new_d_Const(dbgi, lowered_mode, tv_zero);
 264
 265                         ir_node *vals[2] = { one, zero };
 266                         ir_node *psi     = new_rd_Psi(dbgi, irg, block, 1, &node, vals,
 267                                                       lowered_mode);
 268
 269                         set_irn_link(node, psi);
 270                         return psi;
 271                         }
 272                 } else if(is_Proj(pred) && is_Call(get_Proj_pred(pred))) {
 273                         ir_type   *type   = get_Call_type(get_Proj_pred(pred));
 274                         adjust_method_type(type);
 275                         set_irn_mode(node, lowered_mode);
 276                         return node;
 277                 } else if(is_Proj(pred) && is_Start(get_Proj_pred(pred))) {
 278                         ir_entity *entity = get_irg_entity(irg);
 279                         ir_type   *type   = get_entity_type(entity);
 280                         adjust_method_type(type);
 281                         set_irn_mode(node, lowered_mode);
 282                         return node;
 283                 }
 284
 285                 panic("unexpected projb: %+F (pred: %+F)", node, pred);
 286         }
 287         if(op == op_Const) {
 288                 tarval *tv = get_Const_tarval(node);
 289                 if(tv == get_tarval_b_true()) {
 290                         tarval  *tv_one  = get_tarval_one(lowered_mode);
 291                         res              = new_d_Const(dbgi, lowered_mode, tv_one);
 292                 } else if(tv == get_tarval_b_false()) {
 293                         tarval  *tv_zero = get_tarval_null(lowered_mode);
 294                         res              = new_d_Const(dbgi, lowered_mode, tv_zero);
 295                 } else {
 296                         panic("invalid boolean const %+F", node);
 297                 }
 298                 set_irn_link(node, res);
 299                 return res;
 300         }
 301
 302         panic("didn't expect %+F to have mode_b", node);
 303 }
 304
 305 static void lower_mode_b_walker(ir_node *node, void *env)
 306 {
 307         int i, arity;
 308         (void) env;
 309
 310         arity = get_irn_arity(node);
 311         for(i = 0; i < arity; ++i) {
 312                 ir_node *lowered_in;
 313                 ir_node *in = get_irn_n(node, i);
 314                 if(get_irn_mode(in) != mode_b)
 315                         continue;
 316
 317                 if(! lower_direct_cmp) {
 318                         if(is_Cond(node)
 319                                         || (is_Psi(node) && get_irn_mode(node) != mode_b)) {
 320                                 if(is_Proj(in)) {
 321                                         ir_node *pred = get_Proj_pred(in);
 322                                         if(is_Cmp(pred))
 323                                                 continue;
 324                                 }
 325                         }
 326                 }
 327
 328                 lowered_in = lower_node(in);
 329
 330                 if(is_Return(node)) {
 331                         ir_entity *entity = get_irg_entity(current_ir_graph);
 332                         ir_type   *type   = get_entity_type(entity);
 333                         adjust_method_type(type);
 334                 } else if(is_Call(node)) {
 335                         ir_type *type = get_Call_type(node);
 336                         adjust_method_type(type);
 337                 } else {
 338                         lowered_in = create_convb(lowered_in);
 339                 }
 340                 set_irn_n(node, i, lowered_in);
 341         }
 342 }
 343
 344 static void clear_links(ir_node *node, void *env)
 345 {
 346         (void) env;
 347         set_irn_link(node, NULL);
 348 }
 349
 350 void ir_lower_mode_b(ir_graph *irg, ir_mode *mode, int do_lower_direct_cmp)
 351 {
 352         lowered_mode     = mode;
 353         lower_direct_cmp = do_lower_direct_cmp;
 354         set_using_irn_link(irg);
 355         irg_walk_graph(irg, clear_links, NULL, NULL);
 356         irg_walk_graph(irg, lower_mode_b_walker, NULL, NULL);
 357         clear_using_irn_link(irg);
 358 }