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 #include "benode_t.h"
  39
  40 static ir_mode *lowered_mode     = NULL;
  41 static int      lower_direct_cmp = 0;
  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 *lower_node(ir_node *node)
  54 {
  55         ir_graph *irg   = current_ir_graph;
  56         dbg_info *dbgi  = get_irn_dbg_info(node);
  57         ir_op    *op    = get_irn_op(node);
  58         ir_node  *block = get_nodes_block(node);
  59         ir_node  *res;
  60
  61         assert(get_irn_mode(node) == mode_b);
  62
  63         res = get_irn_link(node);
  64         if(res != NULL)
  65                 return res;
  66
  67         /* TODO: be robust against phi-loops... */
  68         if(op == op_Phi) {
  69                 int       i, arity;
  70                 ir_node **in;
  71                 ir_node  *unknown, *new_phi;
  72
  73                 arity = get_irn_arity(node);
  74                 in    = alloca(arity * sizeof(in[0]));
  75                 unknown = new_Unknown(lowered_mode);
  76                 for(i = 0; i < arity; ++i) {
  77                         in[i] = unknown;
  78                 }
  79                 new_phi = new_rd_Phi(dbgi, irg, block, arity, in,
  80                                               lowered_mode);
  81                 set_irn_link(node, new_phi);
  82
  83                 for(i = 0; i < arity; ++i) {
  84                         ir_node *in     = get_irn_n(node, i);
  85                         ir_node *low_in = lower_node(in);
  86
  87                         set_irn_n(new_phi, i, low_in);
  88                 }
  89
  90                 return new_phi;
  91         }
  92
  93         if(op == op_And || op == op_Or || op == op_Eor) {
  94                 int i, arity;
  95                 ir_node *copy = exact_copy(node);
  96
  97                 arity = get_irn_arity(node);
  98                 for(i = 0; i < arity; ++i) {
  99                         ir_node *in     = get_irn_n(node, i);
 100                         ir_node *low_in = lower_node(in);
 101
 102                         set_irn_n(copy, i, low_in);
 103                 }
 104                 set_irn_mode(copy, lowered_mode);
 105
 106                 set_irn_link(node, copy);
 107                 return copy;
 108         }
 109         if(op == op_Not) {
 110                 ir_node *op     = get_Not_op(node);
 111                 ir_node *low_op = lower_node(op);
 112
 113                 res = create_not(dbgi, low_op);
 114                 set_irn_link(node, res);
 115                 return res;
 116         }
 117         if(op == op_Psi) {
 118                 ir_node *cond        = get_Psi_cond(node, 0);
 119                 ir_node *low_cond    = lower_node(cond);
 120                 ir_node *v_true      = get_Psi_val(node, 0);
 121                 ir_node *low_v_true  = lower_node(v_true);
 122                 ir_node *v_false     = get_Psi_default(node);
 123                 ir_node *low_v_false = lower_node(v_false);
 124
 125                 ir_node *and0     = new_rd_And(dbgi, irg, block, low_cond, low_v_true,
 126                                                lowered_mode);
 127
 128                 ir_node *not_cond = create_not(dbgi, low_cond);
 129
 130                 ir_node *and1     = new_rd_And(dbgi, irg, block, not_cond, low_v_false,
 131                                                lowered_mode);
 132
 133                 ir_node *or       = new_rd_Or(dbgi, irg, block, and0, and1,
 134                                               lowered_mode);
 135
 136                 set_irn_link(node, or);
 137                 return or;
 138         }
 139         if(op == op_Conv) {
 140                 tarval  *tv_one   = get_tarval_one(lowered_mode);
 141                 ir_node *one      = new_d_Const(dbgi, lowered_mode, tv_one);
 142                 tarval  *tv_zero  = get_tarval_null(lowered_mode);
 143                 ir_node *zero     = new_d_Const(dbgi, lowered_mode, tv_zero);
 144                 ir_mode *mode     = get_irn_mode(node);
 145                 tarval  *tv_zeroc = get_tarval_null(mode);
 146                 ir_node *zero_cmp = new_d_Const(dbgi, mode, tv_zeroc);
 147
 148                 ir_node *cmp      = new_rd_Cmp(dbgi, irg, block, node, zero_cmp);
 149                 ir_node *proj     = new_rd_Proj(dbgi, irg, block, cmp, mode_b,
 150                                                 pn_Cmp_Lg);
 151                 ir_node *vals[2]  = { one, zero };
 152                 ir_node *psi      = new_rd_Psi(dbgi, irg, block, 1, &proj, vals,
 153                                                lowered_mode);
 154
 155                 set_irn_link(node, psi);
 156                 return psi;
 157         }
 158         if(op == op_Proj) {
 159                 ir_node *pred  = get_Proj_pred(node);
 160
 161                 assert(!is_Load(pred));
 162                 if(is_Cmp(pred)) {
 163                         ir_mode *mode  = get_irn_mode(pred);
 164                         ir_node *left  = get_Cmp_left(pred);
 165                         ir_node *right = get_Cmp_right(pred);
 166
 167                         if( (mode_is_int(mode) || mode_is_reference(mode)) &&
 168                                 (get_mode_size_bits(mode) < get_mode_size_bits(lowered_mode)
 169                                  || classify_Const(right) == CNST_NULL)) {
 170                                 int      pnc      = get_Proj_proj(node);
 171                                 int      need_not = 0;
 172                                 ir_node *a        = NULL;
 173                                 ir_node *b        = NULL;
 174
 175                                 if(pnc == pn_Cmp_Lt) {
 176                                         /* a < b  ->  (a - b) >> 31 */
 177                                         a = left;
 178                                         b = right;
 179                                 } else if(pnc == pn_Cmp_Le) {
 180                                         /* a <= b  -> ((a - b) >> 31) ^ 1 */
 181                                         a        = right;
 182                                         b        = left;
 183                                         need_not = 1;
 184                                 } else if(pnc == pn_Cmp_Gt) {
 185                                         /* a > b   -> (b - a) >> 31 */
 186                                         a = right;
 187                                         b = left;
 188                                 } else if(pnc == pn_Cmp_Ge) {
 189                                         /* a >= b   -> ((a - b) >> 31) ^ 1 */
 190                                         a        = left;
 191                                         b        = right;
 192                                         need_not = 1;
 193                                 }
 194
 195                                 if(a != NULL) {
 196                                         tarval  *tv        = new_tarval_from_long(31, mode_Iu);
 197                                         ir_node *shift_cnt = new_d_Const(dbgi, mode_Iu, tv);
 198
 199                                         if(mode != lowered_mode) {
 200                                                 a = new_rd_Conv(dbgi, irg, block, a, lowered_mode);
 201                                                 b = new_rd_Conv(dbgi, irg, block, b, lowered_mode);
 202                                         }
 203
 204                                         res = new_rd_Sub(dbgi, irg, block, a, b, lowered_mode);
 205                                         res = new_rd_Shr(dbgi, irg, block, res, shift_cnt,
 206                                                          lowered_mode);
 207
 208                                         if(need_not) {
 209                                                 res = create_not(dbgi, res);
 210                                         }
 211                                         set_irn_link(node, res);
 212                                         return res;
 213                                 }
 214                         }
 215
 216                         {
 217                         /* synthesize the 0/1 value */
 218                         tarval  *tv_one  = get_tarval_one(lowered_mode);
 219                         ir_node *one     = new_d_Const(dbgi, lowered_mode, tv_one);
 220                         tarval  *tv_zero = get_tarval_null(lowered_mode);
 221                         ir_node *zero    = new_d_Const(dbgi, lowered_mode, tv_zero);
 222
 223                         ir_node *vals[2] = { one, zero };
 224                         ir_node *psi     = new_rd_Psi(dbgi, irg, block, 1, &node, vals,
 225                                                       lowered_mode);
 226
 227                         set_irn_link(node, psi);
 228                         return psi;
 229                         }
 230                 } else if (be_is_Barrier(pred)) {
 231                         /* nothing to do */
 232                         return node;
 233                 }
 234
 235                 panic("unexpected projb: %+F (pred: %+F)", node, pred);
 236         }
 237         if(op == op_Const) {
 238                 tarval *tv = get_Const_tarval(node);
 239                 if(tv == get_tarval_b_true()) {
 240                         tarval  *tv_one  = get_tarval_one(lowered_mode);
 241                         res              = new_d_Const(dbgi, lowered_mode, tv_one);
 242                 } else if(tv == get_tarval_b_false()) {
 243                         tarval  *tv_zero = get_tarval_null(lowered_mode);
 244                         res              = new_d_Const(dbgi, lowered_mode, tv_zero);
 245                 } else {
 246                         panic("invalid boolean const %+F", node);
 247                 }
 248                 set_irn_link(node, res);
 249                 return res;
 250         }
 251
 252         panic("didn't expect %+F to have mode_b", node);
 253 }
 254
 255 static ir_node *create_convb(ir_node *node)
 256 {
 257         ir_graph *irg   = current_ir_graph;
 258         ir_node  *block = get_nodes_block(node);
 259         ir_node  *conv  = new_rd_Conv(NULL, irg, block, node, mode_b);
 260
 261         return conv;
 262 }
 263
 264 static void lower_mode_b_walker(ir_node *node, void *env)
 265 {
 266         int i, arity;
 267         (void) env;
 268
 269         arity = get_irn_arity(node);
 270         for(i = 0; i < arity; ++i) {
 271                 ir_node *lowered_in;
 272                 ir_node *in = get_irn_n(node, i);
 273                 if(get_irn_mode(in) != mode_b)
 274                         continue;
 275
 276                 if(! lower_direct_cmp) {
 277                         if(is_Cond(node)
 278                                         || (is_Psi(node) && get_irn_mode(node) != mode_b)) {
 279                                 if(is_Proj(in)) {
 280                                         ir_node *pred = get_Proj_pred(in);
 281                                         if(is_Cmp(pred))
 282                                                 continue;
 283                                 }
 284                         }
 285                 }
 286
 287                 lowered_in = lower_node(in);
 288                 lowered_in = create_convb(lowered_in);
 289                 set_irn_n(node, i, lowered_in);
 290         }
 291 }
 292
 293 static void clear_links(ir_node *node, void *env)
 294 {
 295         (void) env;
 296         set_irn_link(node, NULL);
 297 }
 298
 299 void ir_lower_mode_b(ir_graph *irg, ir_mode *mode, int do_lower_direct_cmp)
 300 {
 301         lowered_mode     = mode;
 302         lower_direct_cmp = do_lower_direct_cmp;
 303         set_using_irn_link(irg);
 304         irg_walk_graph(irg, clear_links, NULL, NULL);
 305         irg_walk_graph(irg, lower_mode_b_walker, NULL, NULL);
 306         clear_using_irn_link(irg);
 307 }