cf40e88aacceb5cf4d78344f907c80deac19491e
[libfirm] / ir / be / ia32 / ia32_optimize.c
1 #ifdef HAVE_CONFIG_H
2 #include "config.h"
3 #endif
4
5 #include "irnode.h"
6 #include "irprog_t.h"
7 #include "ircons.h"
8 #include "firm_types.h"
9 #include "iredges.h"
10 #include "tv.h"
11 #include "irgmod.h"
12
13 #include "../benode_t.h"
14
15 #include "ia32_new_nodes.h"
16 #include "bearch_ia32_t.h"
17
18 #undef is_NoMem
19 #define is_NoMem(irn) (get_irn_op(irn) == op_NoMem)
20
21 /**
22  * creates a unique ident by adding a number to a tag
23  *
24  * @param tag   the tag string, must contain a %d if a number
25  *              should be added
26  */
27 static ident *unique_id(const char *tag)
28 {
29         static unsigned id = 0;
30         char str[256];
31
32         snprintf(str, sizeof(str), tag, ++id);
33         return new_id_from_str(str);
34 }
35
36
37
38 /**
39  * Transforms a SymConst.
40  *
41  * @param mod     the debug module
42  * @param block   the block the new node should belong to
43  * @param node    the ir SymConst node
44  * @param mode    mode of the SymConst
45  * @return the created ia32 Const node
46  */
47 static ir_node *gen_SymConst(ia32_transform_env_t *env) {
48         ir_node  *cnst;
49         dbg_info *dbg   = env->dbg;
50         ir_mode  *mode  = env->mode;
51         ir_graph *irg   = env->irg;
52         ir_node  *block = env->block;
53
54         cnst = new_rd_ia32_Const(dbg, irg, block, mode);
55         set_ia32_Const_attr(cnst, env->irn);
56         return cnst;
57 }
58
59 /**
60  * Get a primitive type for a mode.
61  */
62 static ir_type *get_prim_type(pmap *types, ir_mode *mode)
63 {
64         pmap_entry *e = pmap_find(types, mode);
65         ir_type *res;
66
67         if (! e) {
68                 char buf[64];
69                 snprintf(buf, sizeof(buf), "prim_type_%s", get_mode_name(mode));
70                 res = new_type_primitive(new_id_from_str(buf), mode);
71                 pmap_insert(types, mode, res);
72         }
73         else
74                 res = e->value;
75         return res;
76 }
77
78 /**
79  * Get an entity that is initialized with a tarval
80  */
81 static entity *get_entity_for_tv(ia32_code_gen_t *cg, ir_node *cnst)
82 {
83         tarval *tv    = get_Const_tarval(cnst);
84         pmap_entry *e = pmap_find(cg->tv_ent, tv);
85         entity *res;
86         ir_graph *rem;
87
88         if (! e) {
89                 ir_mode *mode = get_irn_mode(cnst);
90                 ir_type *tp = get_Const_type(cnst);
91                 if (tp == firm_unknown_type)
92                         tp = get_prim_type(cg->types, mode);
93
94                 res = new_entity(get_glob_type(), unique_id("ia32FloatCnst_%u"), tp);
95
96                 set_entity_ld_ident(res, get_entity_ident(res));
97                 set_entity_visibility(res, visibility_local);
98                 set_entity_variability(res, variability_constant);
99                 set_entity_allocation(res, allocation_static);
100
101                  /* we create a new entity here: It's initialization must resist on the
102                     const code irg */
103                 rem = current_ir_graph;
104                 current_ir_graph = get_const_code_irg();
105                 set_atomic_ent_value(res, new_Const_type(tv, tp));
106                 current_ir_graph = rem;
107         }
108         else
109                 res = e->value;
110         return res;
111 }
112
113 /**
114  * Transforms a Const.
115  *
116  * @param mod     the debug module
117  * @param block   the block the new node should belong to
118  * @param node    the ir Const node
119  * @param mode    mode of the Const
120  * @return the created ia32 Const node
121  */
122 static ir_node *gen_Const(ia32_transform_env_t *env) {
123         ir_node *cnst;
124         symconst_symbol sym;
125         ir_graph *irg   = env->irg;
126         ir_node  *block = env->block;
127         ir_node  *node  = env->irn;
128         dbg_info *dbg   = env->dbg;
129         ir_mode  *mode  = env->mode;
130
131         if (mode_is_float(mode)) {
132                 sym.entity_p = get_entity_for_tv(env->cg, node);
133
134                 cnst = new_rd_SymConst(dbg, irg, block, sym, symconst_addr_ent);
135                 env->irn = cnst;
136                 cnst = gen_SymConst(env);
137         }
138         else {
139                 cnst = new_rd_ia32_Const(dbg, irg, block, get_irn_mode(node));
140                 set_ia32_Const_attr(cnst, node);
141         }
142         return cnst;
143 }
144
145
146
147 /**
148  * Transforms (all) Const's into ia32_Const and places them in the
149  * block where they are used (or in the cfg-pred Block in case of Phi's)
150  */
151 void ia32_place_consts(ir_node *irn, void *env) {
152         ia32_code_gen_t      *cg = env;
153         ia32_transform_env_t  tenv;
154         ir_mode              *mode;
155         ir_node              *pred, *cnst;
156         int                   i;
157         opcode                opc;
158
159         if (is_Block(irn))
160                 return;
161
162         mode = get_irn_mode(irn);
163
164         tenv.arch_env = cg->arch_env;
165         tenv.block    = get_nodes_block(irn);
166         tenv.cg       = cg;
167         tenv.irg      = cg->irg;
168         tenv.mod      = cg->mod;
169
170         /* Loop over all predecessors and check for Sym/Const nodes */
171         for (i = get_irn_arity(irn) - 1; i >= 0; --i) {
172                 pred      = get_irn_n(irn, i);
173                 cnst      = NULL;
174                 opc       = get_irn_opcode(pred);
175                 tenv.irn  = pred;
176                 tenv.mode = get_irn_mode(pred);
177                 tenv.dbg  = get_irn_dbg_info(pred);
178
179                 /* If it's a Phi, then we need to create the */
180                 /* new Const in it's predecessor block       */
181                 if (is_Phi(irn)) {
182                         tenv.block = get_Block_cfgpred_block(get_nodes_block(irn), i);
183                 }
184
185                 switch (opc) {
186                         case iro_Const:
187                                 cnst = gen_Const(&tenv);
188                                 break;
189                         case iro_SymConst:
190                                 cnst = gen_SymConst(&tenv);
191                                 break;
192                         default:
193                                 break;
194                 }
195
196                 /* if we found a const, then set it */
197                 if (cnst) {
198                         set_irn_n(irn, i, cnst);
199                 }
200         }
201 }
202
203
204 /******************************************************************
205  *              _     _                   __  __           _
206  *     /\      | |   | |                 |  \/  |         | |
207  *    /  \   __| | __| |_ __ ___  ___ ___| \  / | ___   __| | ___
208  *   / /\ \ / _` |/ _` | '__/ _ \/ __/ __| |\/| |/ _ \ / _` |/ _ \
209  *  / ____ \ (_| | (_| | | |  __/\__ \__ \ |  | | (_) | (_| |  __/
210  * /_/    \_\__,_|\__,_|_|  \___||___/___/_|  |_|\___/ \__,_|\___|
211  *
212  ******************************************************************/
213
214 static int node_is_comm(const ir_node *irn) {
215         if (is_ia32_Add(irn)  ||
216                 is_ia32_fAdd(irn) ||
217                 is_ia32_Mul(irn)  ||
218                 is_ia32_Mulh(irn) ||
219                 is_ia32_fMul(irn) ||
220                 is_ia32_And(irn)  ||
221                 is_ia32_fAnd(irn) ||
222                 is_ia32_Or(irn)   ||
223                 is_ia32_fOr(irn)  ||
224                 is_ia32_Eor(irn)  ||
225                 is_ia32_fEor(irn) ||
226                 is_ia32_Min(irn)  ||
227                 is_ia32_fMin(irn) ||
228                 is_ia32_Max(irn)  ||
229                 is_ia32_fMax(irn))
230         {
231                 return 1;
232         }
233
234         return 0;
235 }
236
237 /**
238  * Returns the first mode_M Proj connected to irn.
239  */
240 static ir_node *get_mem_proj(const ir_node *irn) {
241         const ir_edge_t *edge;
242         ir_node         *src;
243
244         assert(get_irn_mode(irn) == mode_T && "expected mode_T node");
245
246         foreach_out_edge(irn, edge) {
247                 src = get_edge_src_irn(edge);
248
249                 assert(is_Proj(src) && "Proj expected");
250
251                 if (get_irn_mode(src) == mode_M)
252                         return src;
253         }
254
255         return NULL;
256 }
257
258 /**
259  * Returns the Proj with number 0 connected to irn.
260  */
261 static ir_node *get_res_proj(const ir_node *irn) {
262         const ir_edge_t *edge;
263         ir_node         *src;
264
265         assert(get_irn_mode(irn) == mode_T && "expected mode_T node");
266
267         foreach_out_edge(irn, edge) {
268                 src = get_edge_src_irn(edge);
269
270                 assert(is_Proj(src) && "Proj expected");
271
272                 if (get_Proj_proj(src) == 0)
273                         return src;
274         }
275
276         return NULL;
277 }
278
279
280 /**
281  * Determines if irn is a Proj and if is_op_func returns true for it's predecessor.
282  */
283 static int pred_is_specific_node(const ir_node *irn, int (*is_op_func)(const ir_node *n)) {
284         if (is_Proj(irn) && is_op_func(get_Proj_pred(irn))) {
285                 return 1;
286         }
287
288         return 0;
289 }
290
291 /**
292  * Folds Add or Sub to LEA if possible
293  */
294 static ir_node *fold_addr(ir_node *irn, firm_dbg_module_t *mod, ir_node *noreg) {
295         ir_graph *irg      = get_irn_irg(irn);
296         ir_mode  *mode     = get_irn_mode(irn);
297         dbg_info *dbg      = get_irn_dbg_info(irn);
298         ir_node  *block    = get_nodes_block(irn);
299         ir_node  *res      = irn;
300         char     *offs     = NULL;
301         char     *new_offs = NULL;
302         int       scale    = 0;
303         int       isadd    = 0;
304         int       dolea    = 0;
305         ir_node  *left, *right, *temp;
306         ir_node  *base, *index;
307         ia32_am_flavour_t am_flav;
308
309         if (is_ia32_Add(irn))
310                 isadd = 1;
311
312         left  = get_irn_n(irn, 2);
313         right = get_irn_n(irn, 3);
314
315         /* "normalize" arguments in case of add */
316         if  (isadd) {
317                 /* put LEA == ia32_am_O as right operand */
318                 if (is_ia32_Lea(left) && get_ia32_am_flavour(left) == ia32_am_O) {
319                         set_irn_n(irn, 2, right);
320                         set_irn_n(irn, 3, left);
321                         temp  = left;
322                         left  = right;
323                         right = temp;
324                 }
325
326                 /* put LEA != ia32_am_O as left operand */
327                 if (is_ia32_Lea(right) && get_ia32_am_flavour(right) != ia32_am_O) {
328                         set_irn_n(irn, 2, right);
329                         set_irn_n(irn, 3, left);
330                         temp  = left;
331                         left  = right;
332                         right = temp;
333                 }
334
335                 /* put SHL as right operand */
336                 if (pred_is_specific_node(left, is_ia32_Shl)) {
337                         set_irn_n(irn, 2, right);
338                         set_irn_n(irn, 3, left);
339                         temp  = left;
340                         left  = right;
341                         right = temp;
342                 }
343         }
344
345         /* Left operand could already be a LEA */
346         if (is_ia32_Lea(left)) {
347                 DBG((mod, LEVEL_1, "\tgot LEA as left operand\n"));
348
349                 base  = get_irn_n(left, 0);
350                 index = get_irn_n(left, 1);
351                 offs  = get_ia32_am_offs(left);
352                 scale = get_ia32_am_scale(left);
353         }
354         else {
355                 base  = left;
356                 index = noreg;
357                 offs  = NULL;
358                 scale = 0;
359
360         }
361
362         /* check if operand is either const or right operand is AMConst (LEA with ia32_am_O) */
363         if (get_ia32_cnst(irn)) {
364                 DBG((mod, LEVEL_1, "\tfound op with imm"));
365
366                 new_offs = get_ia32_cnst(irn);
367                 dolea    = 1;
368         }
369         else if (is_ia32_Lea(right) && get_ia32_am_flavour(right) == ia32_am_O) {
370                 DBG((mod, LEVEL_1, "\tgot op with LEA am_O"));
371
372                 new_offs = get_ia32_am_offs(right);
373                 dolea    = 1;
374         }
375         /* we can only get an additional index if there isn't already one */
376         else if (isadd && be_is_NoReg(index)) {
377                 /* default for add -> make right operand to index */
378                 index = right;
379                 dolea = 1;
380
381                 DBG((mod, LEVEL_1, "\tgot LEA candidate with index %+F\n", index));
382                 /* check for SHL 1,2,3 */
383                 if (pred_is_specific_node(right, is_ia32_Shl)) {
384                         temp = get_Proj_pred(right);
385
386                         if (get_ia32_Immop_tarval(temp)) {
387                                 scale = get_tarval_long(get_ia32_Immop_tarval(temp));
388
389                                 if (scale <= 3) {
390                                         scale = 1 << scale;
391                                         index = get_irn_n(temp, 2);
392
393                                         DBG((mod, LEVEL_1, "\tgot scaled index %+F\n", index));
394                                 }
395                         }
396                 }
397         }
398
399         /* ok, we can create a new LEA */
400         if (dolea) {
401                 res = new_rd_ia32_Lea(dbg, irg, block, base, index, mode_Is);
402
403                 /* add the old offset of a previous LEA */
404                 if (offs) {
405                         add_ia32_am_offs(res, offs);
406                 }
407
408                 /* add the new offset */
409                 if (isadd) {
410                         if (new_offs) {
411                                 add_ia32_am_offs(res, new_offs);
412                         }
413                 }
414                 else {
415                         sub_ia32_am_offs(res, new_offs);
416                 }
417
418                 /* set scale */
419                 set_ia32_am_scale(res, scale);
420
421                 am_flav = ia32_am_N;
422                 /* determine new am flavour */
423                 if (offs || new_offs) {
424                         am_flav |= ia32_O;
425                 }
426                 if (! be_is_NoReg(base)) {
427                         am_flav |= ia32_B;
428                 }
429                 if (! be_is_NoReg(index)) {
430                         am_flav |= ia32_I;
431                 }
432                 if (scale > 0) {
433                         am_flav |= ia32_S;
434                 }
435                 set_ia32_am_flavour(res, am_flav);
436
437                 set_ia32_op_type(res, ia32_AddrModeS);
438
439                 DBG((mod, LEVEL_1, "\tLEA [%+F + %+F * %d + %s]\n", base, index, scale, get_ia32_am_offs(res)));
440
441                 /* get the result Proj of the Add/Sub */
442                 irn = get_res_proj(irn);
443
444                 assert(irn && "Couldn't find result proj");
445
446                 /* exchange the old op with the new LEA */
447                 exchange(irn, res);
448         }
449
450         return res;
451 }
452
453 /**
454  * Optimizes a pattern around irn to address mode if possible.
455  */
456 void ia32_optimize_am(ir_node *irn, void *env) {
457         ia32_code_gen_t   *cg  = env;
458         ir_graph          *irg = cg->irg;
459         firm_dbg_module_t *mod = cg->mod;
460         ir_node           *res = irn;
461         dbg_info          *dbg;
462         ir_mode           *mode;
463         ir_node           *block, *noreg_gp, *noreg_fp;
464         ir_node           *left, *right, *temp;
465         ir_node           *store, *mem_proj;
466         ir_node           *succ, *addr_b, *addr_i;
467         int                check_am_src = 0;
468
469         if (! is_ia32_irn(irn))
470                 return;
471
472         dbg      = get_irn_dbg_info(irn);
473         mode     = get_irn_mode(irn);
474         block    = get_nodes_block(irn);
475         noreg_gp = ia32_new_NoReg_gp(cg);
476         noreg_fp = ia32_new_NoReg_fp(cg);
477
478         DBG((mod, LEVEL_1, "checking for AM\n"));
479
480         /* 1st part: check for address calculations and transform the into Lea */
481
482         /* Following cases can occur: */
483         /* - Sub (l, imm) -> LEA [base - offset] */
484         /* - Sub (l, r == LEA with ia32_am_O)   -> LEA [base - offset] */
485         /* - Add (l, imm) -> LEA [base + offset] */
486         /* - Add (l, r == LEA with ia32_am_O)  -> LEA [base + offset] */
487         /* - Add (l == LEA with ia32_am_O, r)  -> LEA [base + offset] */
488         /* - Add (l, r) -> LEA [base + index * scale] */
489         /*              with scale > 1 iff l/r == shl (1,2,3) */
490
491         if (is_ia32_Sub(irn) || is_ia32_Add(irn)) {
492                 left  = get_irn_n(irn, 2);
493                 right = get_irn_n(irn, 3);
494
495             /* Do not try to create a LEA if one of the operands is a Load. */
496                 if (! pred_is_specific_node(left,  is_ia32_Load)  &&
497                         ! pred_is_specific_node(right, is_ia32_Load))
498                 {
499                         res = fold_addr(irn, mod, noreg_gp);
500                 }
501         }
502
503         /* 2nd part: fold following patterns:
504         /* - Load  -> LEA into Load  } TODO: If the LEA is used by more than one Load/Store */
505         /* - Store -> LEA into Store }       it might be better to keep the LEA             */
506         /* - op -> Load into AMop with am_Source
507         /*   conditions:                */
508         /*     - op is am_Source capable AND   */
509         /*     - the Load is only used by this op AND */
510         /*     - the Load is in the same block */
511         /* - Store -> op -> Load  into AMop with am_Dest  */
512         /*   conditions:                */
513         /*     - op is am_Dest capable AND   */
514         /*     - the Store uses the same address as the Load AND */
515         /*     - the Load is only used by this op AND */
516         /*     - the Load and Store are in the same block AND  */
517         /*     - nobody else uses the result of the op */
518
519         if ((res == irn) && (get_ia32_am_support(irn) != ia32_am_None) && !is_ia32_Lea(irn)) {
520                 /* 1st: check for Load/Store -> LEA   */
521                 if (is_ia32_Load(irn)  || is_ia32_fLoad(irn) ||
522                         is_ia32_Store(irn) || is_ia32_fStore(irn))
523                 {
524                         left = get_irn_n(irn, 0);
525
526                         if (is_ia32_Lea(left)) {
527                                 /* get the AM attributes from the LEA */
528                                 add_ia32_am_offs(irn, get_ia32_am_offs(left));
529                                 set_ia32_am_scale(irn, get_ia32_am_scale(left));
530                                 set_ia32_am_flavour(irn, get_ia32_am_flavour(left));
531                                 set_ia32_op_type(irn, get_ia32_op_type(left));
532
533                                 /* set base and index */
534                                 set_irn_n(irn, 0, get_irn_n(left, 0));
535                                 set_irn_n(irn, 1, get_irn_n(left, 1));
536                         }
537                 }
538                 /* check if at least one operand is a Load */
539                 else if (pred_is_specific_node(get_irn_n(irn, 2), is_ia32_Load)  ||
540                                  pred_is_specific_node(get_irn_n(irn, 2), is_ia32_fLoad) ||
541                                  pred_is_specific_node(get_irn_n(irn, 3), is_ia32_Load)  ||
542                                  pred_is_specific_node(get_irn_n(irn, 3), is_ia32_fLoad))
543                 {
544
545                         /* normalize commutative ops */
546                         if (node_is_comm(irn)) {
547                                 left  = get_irn_n(irn, 2);
548                                 right = get_irn_n(irn, 3);
549
550                                 /* assure that Left operand is always a Load if there is one */
551                                 if (pred_is_specific_node(right, is_ia32_Load) ||
552                                         pred_is_specific_node(right, is_ia32_fLoad))
553                                 {
554                                         set_irn_n(irn, 2, right);
555                                         set_irn_n(irn, 3, left);
556
557                                         temp  = left;
558                                         left  = right;
559                                         right = temp;
560                                 }
561                         }
562
563                         /* check for Store -> op -> Load */
564
565                         /* Store -> op -> Load optimization is only possible if supported by op */
566                         if (get_ia32_am_support(irn) & ia32_am_Dest) {
567
568                                 /* An address mode capable op always has a result Proj.                  */
569                                 /* If this Proj is used by more than one other node, we don't need to    */
570                                 /* check further, otherwise we check for Store and remember the address, */
571                                 /* the Store points to. */
572
573                                 succ = get_res_proj(irn);
574                                 assert(succ && "Couldn't find result proj");
575
576                                 addr_b = NULL;
577                                 addr_i = NULL;
578                                 store  = NULL;
579
580                                 /* now check for users and Store */
581                                 if (get_irn_n_edges(succ) == 1) {
582                                         succ = get_edge_src_irn(get_irn_out_edge_first(succ));
583
584                                         if (is_ia32_fStore(succ) || is_ia32_Store(succ)) {
585                                                 store  = succ;
586                                                 addr_b = get_irn_n(store, 0);
587
588                                                 /* Could be that the Store is connected to the address    */
589                                                 /* calculating LEA while the Load is already transformed. */
590                                                 if (is_ia32_Lea(addr_b)) {
591                                                         succ   = addr_b;
592                                                         addr_b = get_irn_n(succ, 0);
593                                                         addr_i = get_irn_n(succ, 1);
594                                                 }
595                                                 else {
596                                                         addr_i = noreg_gp;
597                                                 }
598                                         }
599                                 }
600
601                                 if (store) {
602                                         /* we found a Store as single user: Now check for Load */
603                                         left  = get_irn_n(irn, 2);
604                                         right = get_irn_n(irn, 3);
605
606                                         /* Could be that the right operand is also a Load, so we make */
607                                         /* sure that the "interesting" Load is always the left one    */
608
609                                         /* right != NoMem means, we have a "binary" operation */
610                                         if (! is_NoMem(right) &&
611                                                 (pred_is_specific_node(right, is_ia32_Load) ||
612                                                  pred_is_specific_node(right, is_ia32_fLoad)))
613                                         {
614                                                 if ((addr_b == get_irn_n(get_Proj_pred(right), 0)) &&
615                                                         (addr_i == get_irn_n(get_Proj_pred(right), 1)))
616                                                 {
617                                                         /* We exchange left and right, so it's easier to kill     */
618                                                         /* the correct Load later and to handle unary operations. */
619                                                         set_irn_n(irn, 2, right);
620                                                         set_irn_n(irn, 3, left);
621
622                                                         temp  = left;
623                                                         left  = right;
624                                                         right = temp;
625                                                 }
626                                         }
627
628                                         /* skip the Proj for easier access */
629                                         left  = get_Proj_pred(left);
630
631                                         /* Compare Load and Store address */
632                                         if ((addr_b == get_irn_n(left, 0)) && (addr_i == get_irn_n(left, 1)))
633                                         {
634                                                 /* Left Load is from same address, so we can */
635                                                 /* disconnect the Load and Store here        */
636
637                                                 /* set new base, index and attributes */
638                                                 set_irn_n(irn, 0, addr_b);
639                                                 set_irn_n(irn, 1, addr_i);
640                                                 add_ia32_am_offs(irn, get_ia32_am_offs(left));
641                                                 set_ia32_am_scale(irn, get_ia32_am_scale(left));
642                                                 set_ia32_am_flavour(irn, get_ia32_am_flavour(left));
643                                                 set_ia32_op_type(irn, ia32_AddrModeD);
644
645                                                 /* connect to Load memory */
646                                                 if (get_irn_arity(irn) == 5) {
647                                                         /* binary AMop */
648                                                         set_irn_n(irn, 4, get_irn_n(left, 2));
649                                                 }
650                                                 else {
651                                                         /* unary AMop */
652                                                         set_irn_n(irn, 3, get_irn_n(left, 2));
653                                                 }
654
655                                                 /* disconnect from Load */
656                                                 set_irn_n(irn, 2, noreg_gp);
657
658                                                 /* connect the memory Proj of the Store to the op */
659                                                 mem_proj = get_mem_proj(store);
660                                                 set_Proj_pred(mem_proj, irn);
661                                                 set_Proj_proj(mem_proj, 1);
662                                         }
663                                 } /* if (store) */
664                                 else if (get_ia32_am_support(irn) & ia32_am_Source) {
665                                         /* There was no store, check if we still can optimize for source address mode */
666                                         check_am_src = 1;
667                                 }
668                         } /* if (support AM Dest) */
669                         else {
670                                 /* op doesn't support am AM Dest -> check for AM Source */
671                                 check_am_src = 1;
672                         }
673
674                         /* optimize op -> Load iff Load is only used by this op */
675                         if (check_am_src) {
676                                 left = get_irn_n(irn, 2);
677
678                                 if (get_irn_n_edges(left) == 1) {
679                                         left = get_Proj_pred(left);
680
681                                         addr_b = get_irn_n(left, 0);
682                                         addr_i = get_irn_n(left, 1);
683
684                                         /* set new base, index and attributes */
685                                         set_irn_n(irn, 0, addr_b);
686                                         set_irn_n(irn, 1, addr_i);
687                                         add_ia32_am_offs(irn, get_ia32_am_offs(left));
688                                         set_ia32_am_scale(irn, get_ia32_am_scale(left));
689                                         set_ia32_am_flavour(irn, get_ia32_am_flavour(left));
690                                         set_ia32_op_type(irn, ia32_AddrModeS);
691
692                                         /* connect to Load memory */
693                                         if (get_irn_arity(irn) == 5) {
694                                                 /* binary AMop */
695                                                 set_irn_n(irn, 4, get_irn_n(left, 2));
696                                         }
697                                         else {
698                                                 /* unary AMop */
699                                                 set_irn_n(irn, 3, get_irn_n(left, 2));
700                                         }
701
702                                         /* disconnect from Load */
703                                         set_irn_n(irn, 2, noreg_gp);
704
705                                         /* If Load has a memory Proj, connect it to the op */
706                                         mem_proj = get_mem_proj(left);
707                                         if (mem_proj) {
708                                                 set_Proj_pred(mem_proj, irn);
709                                                 set_Proj_proj(mem_proj, 1);
710                                         }
711                                 }
712                         }
713                 }
714         }
715 }