2 * Copyright (C) 1995-2008 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 some High-level constructs, moved from the firmlower.
23 * @author Boris Boesler, Goetz Lindenmaier, Michael Beck
41 * Lower a Sel node. Do not touch Sels accessing entities on the frame type.
43 static void lower_sel(ir_node *sel)
45 ir_graph *irg = get_irn_irg(sel);
46 ir_entity *ent = get_Sel_entity(sel);
47 ir_type *owner = get_entity_owner(ent);
48 dbg_info *dbg = get_irn_dbg_info(sel);
49 ir_mode *mode = get_irn_mode(sel);
50 ir_node *bl = get_nodes_block(sel);
53 /* we can only replace Sels when the layout of the owner type is decided. */
54 if (get_type_state(owner) != layout_fixed)
57 if (0 < get_Sel_n_indexs(sel)) {
59 ir_type *basetyp = get_entity_type(ent);
62 if (is_Primitive_type(basetyp))
63 basemode = get_type_mode(basetyp);
65 basemode = mode_P_data;
67 assert(basemode && "no mode for lowering Sel");
68 assert((get_mode_size_bits(basemode) % 8 == 0) && "can not deal with unorthodox modes");
69 index = get_Sel_index(sel, 0);
71 if (is_Array_type(owner)) {
72 ir_type *arr_ty = owner;
73 size_t dims = get_array_n_dimensions(arr_ty);
74 size_t *map = ALLOCAN(size_t, dims);
75 ir_mode *mode_Int = get_reference_mode_signed_eq(mode);
80 assert(dims == (size_t)get_Sel_n_indexs(sel)
81 && "array dimension must match number of indices of Sel node");
83 for (i = 0; i < dims; i++) {
84 size_t order = get_array_order(arr_ty, i);
86 assert(order < dims &&
87 "order of a dimension must be smaller than the arrays dim");
90 newn = get_Sel_ptr(sel);
92 /* Size of the array element */
93 tv = new_tarval_from_long(get_type_size_bytes(basetyp), mode_Int);
94 last_size = new_rd_Const(dbg, irg, tv);
97 * We compute the offset part of dimension d_i recursively
98 * with the the offset part of dimension d_{i-1}
100 * off_0 = sizeof(array_element_type);
101 * off_i = (u_i - l_i) * off_{i-1} ; i >= 1
103 * whereas u_i is the upper bound of the current dimension
104 * and l_i the lower bound of the current dimension.
106 for (i = dims; i > 0;) {
107 size_t dim = map[--i];
108 ir_node *lb, *ub, *elms, *n, *ind;
111 lb = get_array_lower_bound(arr_ty, dim);
112 ub = get_array_upper_bound(arr_ty, dim);
114 assert(irg == current_ir_graph);
115 if (! is_Unknown(lb))
116 lb = new_rd_Conv(dbg, bl, copy_const_value(get_irn_dbg_info(sel), lb, bl), mode_Int);
120 if (! is_Unknown(ub))
121 ub = new_rd_Conv(dbg, bl, copy_const_value(get_irn_dbg_info(sel), ub, bl), mode_Int);
126 * If the array has more than one dimension, lower and upper
127 * bounds have to be set in the non-last dimension.
130 assert(lb != NULL && "lower bound has to be set in multi-dim array");
131 assert(ub != NULL && "upper bound has to be set in multi-dim array");
133 /* Elements in one Dimension */
134 elms = new_rd_Sub(dbg, bl, ub, lb, mode_Int);
137 ind = new_rd_Conv(dbg, bl, get_Sel_index(sel, dim), mode_Int);
140 * Normalize index, id lower bound is set, also assume
144 ind = new_rd_Sub(dbg, bl, ind, lb, mode_Int);
146 n = new_rd_Mul(dbg, bl, ind, last_size, mode_Int);
152 last_size = new_rd_Mul(dbg, bl, last_size, elms, mode_Int);
154 newn = new_rd_Add(dbg, bl, newn, n, mode);
158 ir_mode *idx_mode = get_irn_mode(index);
159 ir_tarval *tv = new_tarval_from_long(get_mode_size_bytes(basemode), idx_mode);
161 newn = new_rd_Add(dbg, bl, get_Sel_ptr(sel),
162 new_rd_Mul(dbg, bl, index,
163 new_r_Const(irg, tv),
167 } else if (is_Method_type(get_entity_type(ent)) && is_Class_type(owner)) {
168 /* We need an additional load when accessing methods from a dispatch
170 * Matze TODO: Is this really still used? At least liboo does its own
171 * lowering of Method-Sels...
173 ir_mode *ent_mode = get_type_mode(get_entity_type(ent));
174 int offset = get_entity_offset(ent);
175 ir_mode *mode_Int = get_reference_mode_signed_eq(mode);
176 ir_tarval *tv = new_tarval_from_long(offset, mode_Int);
177 ir_node *cnst = new_rd_Const(dbg, irg, tv);
178 ir_node *add = new_rd_Add(dbg, bl, get_Sel_ptr(sel), cnst, mode);
179 ir_node *mem = get_Sel_mem(sel);
180 newn = new_rd_Load(dbg, bl, mem, add, ent_mode, cons_none);
181 newn = new_r_Proj(newn, ent_mode, pn_Load_res);
183 int offset = get_entity_offset(ent);
185 /* replace Sel by add(obj, const(ent.offset)) */
186 newn = get_Sel_ptr(sel);
188 ir_mode *mode_UInt = get_reference_mode_unsigned_eq(mode);
189 ir_tarval *tv = new_tarval_from_long(offset, mode_UInt);
190 ir_node *cnst = new_r_Const(irg, tv);
191 newn = new_rd_Add(dbg, bl, newn, cnst, mode);
202 * Lower a all possible SymConst nodes.
204 static void lower_symconst(ir_node *symc)
214 switch (get_SymConst_kind(symc)) {
215 case symconst_type_size:
216 /* rewrite the SymConst node by a Const node */
217 irg = get_irn_irg(symc);
218 tp = get_SymConst_type(symc);
219 assert(get_type_state(tp) == layout_fixed);
220 mode = get_irn_mode(symc);
221 newn = new_r_Const_long(irg, mode, get_type_size_bytes(tp));
225 exchange(symc, newn);
227 case symconst_type_align:
228 /* rewrite the SymConst node by a Const node */
229 irg = get_irn_irg(symc);
230 tp = get_SymConst_type(symc);
231 assert(get_type_state(tp) == layout_fixed);
232 mode = get_irn_mode(symc);
233 newn = new_r_Const_long(irg, mode, get_type_alignment_bytes(tp));
237 exchange(symc, newn);
239 case symconst_addr_ent:
242 case symconst_ofs_ent:
243 /* rewrite the SymConst node by a Const node */
244 irg = get_irn_irg(symc);
245 ent = get_SymConst_entity(symc);
246 assert(get_type_state(get_entity_type(ent)) == layout_fixed);
247 mode = get_irn_mode(symc);
248 newn = new_r_Const_long(irg, mode, get_entity_offset(ent));
252 exchange(symc, newn);
254 case symconst_enum_const:
255 /* rewrite the SymConst node by a Const node */
256 irg = get_irn_irg(symc);
257 ec = get_SymConst_enum(symc);
258 assert(get_type_state(get_enumeration_owner(ec)) == layout_fixed);
259 tv = get_enumeration_value(ec);
260 newn = new_r_Const(irg, tv);
264 exchange(symc, newn);
268 assert(!"unknown SymConst kind");
271 } /* lower_symconst */
274 * Checks, whether a size is an integral size
276 * @param size the size on bits
278 static int is_integral_size(int size)
283 /* must be at least byte size */
285 } /* is_integral_size */
288 * lower bitfield load access.
290 * @param proj the Proj(result) node
291 * @param load the Load node
293 static void lower_bitfields_loads(ir_node *proj, ir_node *load)
295 ir_node *sel = get_Load_ptr(load);
296 ir_node *block, *res, *ptr;
300 ir_mode *bf_mode, *mode;
301 int offset, bit_offset, bits, bf_bits, old_cse;
307 ent = get_Sel_entity(sel);
308 bf_type = get_entity_type(ent);
310 /* must be a bitfield type */
311 if (!is_Primitive_type(bf_type) || get_primitive_base_type(bf_type) == NULL)
314 /* We have a bitfield access, if either a bit offset is given, or
315 the size is not integral. */
316 bf_mode = get_type_mode(bf_type);
320 mode = get_irn_mode(proj);
321 block = get_nodes_block(proj);
322 bf_bits = get_mode_size_bits(bf_mode);
323 bit_offset = get_entity_offset_bits_remainder(ent);
325 if (bit_offset == 0 && is_integral_size(bf_bits) && bf_mode == get_Load_mode(load))
328 bits = get_mode_size_bits(mode);
329 offset = get_entity_offset(ent);
332 * ok, here we are: now convert the Proj_mode_bf(Load) into And(Shr(Proj_mode(Load)) for unsigned
333 * and Shr(Shl(Proj_mode(load)) for signed
336 /* abandon bitfield sel */
337 irg = get_irn_irg(sel);
338 ptr = get_Sel_ptr(sel);
339 db = get_irn_dbg_info(sel);
340 ptr = new_rd_Add(db, block, ptr, new_r_Const_long(irg, mode_Is, offset), get_irn_mode(ptr));
342 set_Load_ptr(load, ptr);
343 set_Load_mode(load, mode);
346 /* create new proj, switch off CSE or we may get the old one back */
347 old_cse = get_opt_cse();
349 res = new_r_Proj(load, mode, pn_Load_res);
350 set_opt_cse(old_cse);
352 if (mode_is_signed(mode)) { /* signed */
353 int shift_count_up = bits - (bf_bits + bit_offset);
354 int shift_count_down = bits - bf_bits;
356 if (shift_count_up) {
357 res = new_r_Shl(block, res, new_r_Const_long(irg, mode_Iu, shift_count_up), mode);
359 if (shift_count_down) {
360 res = new_r_Shrs(block, res, new_r_Const_long(irg, mode_Iu, shift_count_down), mode);
362 } else { /* unsigned */
363 int shift_count_down = bit_offset;
364 unsigned mask = ((unsigned)-1) >> (bits - bf_bits);
366 if (shift_count_down) {
367 res = new_r_Shr(block, res, new_r_Const_long(irg, mode_Iu, shift_count_down), mode);
369 if (bits != bf_bits) {
370 res = new_r_And(block, res, new_r_Const_long(irg, mode, mask), mode);
375 } /* lower_bitfields_loads */
378 * lower bitfield store access.
380 * @todo: It adds a load which may produce an exception!
382 static void lower_bitfields_stores(ir_node *store)
384 ir_node *sel = get_Store_ptr(store);
385 ir_node *ptr, *value;
388 ir_mode *bf_mode, *mode;
389 ir_node *mem, *irn, *block;
391 unsigned mask, neg_mask;
392 int bf_bits, bits_mask, offset, bit_offset;
395 /* check bitfield access */
399 ent = get_Sel_entity(sel);
400 bf_type = get_entity_type(ent);
402 /* must be a bitfield type */
403 if (!is_Primitive_type(bf_type) || get_primitive_base_type(bf_type) == NULL)
406 /* We have a bitfield access, if either a bit offset is given, or
407 the size is not integral. */
408 bf_mode = get_type_mode(bf_type);
412 value = get_Store_value(store);
413 mode = get_irn_mode(value);
414 block = get_nodes_block(store);
416 bf_bits = get_mode_size_bits(bf_mode);
417 bit_offset = get_entity_offset_bits_remainder(ent);
419 if (bit_offset == 0 && is_integral_size(bf_bits) && bf_mode == get_irn_mode(value))
423 * ok, here we are: now convert the Store(Sel(), value) into Or(And(Load(Sel),c), And(Value,c))
425 mem = get_Store_mem(store);
426 offset = get_entity_offset(ent);
428 bits_mask = get_mode_size_bits(mode) - bf_bits;
429 mask = ((unsigned)-1) >> bits_mask;
433 /* abandon bitfield sel */
434 irg = get_irn_irg(sel);
435 ptr = get_Sel_ptr(sel);
436 db = get_irn_dbg_info(sel);
437 ptr = new_rd_Add(db, block, ptr, new_r_Const_long(irg, mode_Is, offset), get_irn_mode(ptr));
440 /* there are some bits, normal case */
441 irn = new_r_Load(block, mem, ptr, mode, cons_none);
442 mem = new_r_Proj(irn, mode_M, pn_Load_M);
443 irn = new_r_Proj(irn, mode, pn_Load_res);
445 irn = new_r_And(block, irn, new_r_Const_long(irg, mode, neg_mask), mode);
447 if (bit_offset > 0) {
448 value = new_r_Shl(block, value, new_r_Const_long(irg, mode_Iu, bit_offset), mode);
451 value = new_r_And(block, value, new_r_Const_long(irg, mode, mask), mode);
453 value = new_r_Or(block, value, irn, mode);
456 set_Store_mem(store, mem);
457 set_Store_value(store, value);
458 set_Store_ptr(store, ptr);
459 } /* lower_bitfields_stores */
462 * lowers IR-nodes, called from walker
464 static void lower_irnode(ir_node *irn, void *env)
467 switch (get_irn_opcode(irn)) {
475 exchange(irn, get_Cast_op(irn));
483 * Walker: lowers IR-nodes for bitfield access
485 static void lower_bf_access(ir_node *irn, void *env)
488 switch (get_irn_opcode(irn)) {
491 long proj = get_Proj_proj(irn);
492 ir_node *pred = get_Proj_pred(irn);
494 if (proj == pn_Load_res && is_Load(pred))
495 lower_bitfields_loads(irn, pred);
499 lower_bitfields_stores(irn);
508 * Replaces SymConsts by a real constant if possible.
509 * Replace Sel nodes by address computation. Also resolves array access.
510 * Handle Bitfields by added And/Or calculations.
512 void lower_highlevel_graph(ir_graph *irg)
514 if (is_irg_state(irg, IR_GRAPH_STATE_IMPLICIT_BITFIELD_MASKING)) {
515 /* First step: lower bitfield access: must be run as long as Sels still
517 irg_walk_graph(irg, NULL, lower_bf_access, NULL);
520 /* Finally: lower SymConst-Size and Sel nodes, Casts, unaligned Load/Stores. */
521 irg_walk_graph(irg, NULL, lower_irnode, NULL);
524 typedef struct pass_t {
525 ir_graph_pass_t pass;
529 * Wrapper for running lower_highlevel_graph() as an ir_graph pass.
531 static int lower_highlevel_graph_wrapper(ir_graph *irg, void *context)
535 lower_highlevel_graph(irg);
537 } /* lower_highlevel_graph_wrapper */
539 ir_graph_pass_t *lower_highlevel_graph_pass(const char *name)
541 pass_t *pass = XMALLOCZ(pass_t);
543 return def_graph_pass_constructor(
544 &pass->pass, name ? name : "lower_hl", lower_highlevel_graph_wrapper);
545 } /* lower_highlevel_graph_pass */
548 * does the same as lower_highlevel() for all nodes on the const code irg
550 void lower_const_code(void)
552 walk_const_code(NULL, lower_irnode, NULL);
553 } /* lower_const_code */
555 ir_prog_pass_t *lower_const_code_pass(const char *name)
557 return def_prog_pass(name ? name : "lower_const_code", lower_const_code);
561 * Replaces SymConsts by a real constant if possible.
562 * Replace Sel nodes by address computation. Also resolves array access.
563 * Handle Bitfields by added And/Or calculations.
565 void lower_highlevel()
569 n = get_irp_n_irgs();
570 for (i = 0; i < n; ++i) {
571 ir_graph *irg = get_irp_irg(i);
572 lower_highlevel_graph(irg);
575 } /* lower_highlevel */