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44037a66 TG |
1 | /* Medium-level subroutines: convert bit-field store and extract |
2 | and shifts, multiplies and divides to rtl instructions. | |
3 | Copyright (C) 1987, 1988, 1989, 1992 Free Software Foundation, Inc. | |
4 | ||
5 | This file is part of GNU CC. | |
6 | ||
7 | GNU CC is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 2, or (at your option) | |
10 | any later version. | |
11 | ||
12 | GNU CC is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with GNU CC; see the file COPYING. If not, write to | |
19 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
20 | ||
21 | ||
22 | #include "config.h" | |
23 | #include "rtl.h" | |
24 | #include "tree.h" | |
25 | #include "flags.h" | |
26 | #include "insn-flags.h" | |
27 | #include "insn-codes.h" | |
28 | #include "insn-config.h" | |
29 | #include "expr.h" | |
30 | #include "real.h" | |
31 | #include "recog.h" | |
32 | ||
33 | static rtx extract_split_bit_field (); | |
34 | static rtx extract_fixed_bit_field (); | |
35 | static void store_split_bit_field (); | |
36 | static void store_fixed_bit_field (); | |
37 | static rtx mask_rtx (); | |
38 | static rtx lshift_value (); | |
39 | ||
40 | #define CEIL(x,y) (((x) + (y) - 1) / (y)) | |
41 | ||
42 | /* Non-zero means multiply instructions are cheaper than shifts. */ | |
43 | int mult_is_very_cheap; | |
44 | ||
45 | /* Non-zero means divides or modulus operations are relatively cheap for | |
46 | powers of two, so don't use branches; emit the operation instead. | |
47 | Usually, this will mean that the MD file will emit non-branch | |
48 | sequences. */ | |
49 | ||
50 | static int sdiv_pow2_cheap, smod_pow2_cheap; | |
51 | ||
52 | /* Cost of various pieces of RTL. */ | |
53 | static int add_cost, shift_cost, mult_cost, negate_cost, lea_cost; | |
54 | ||
55 | /* Max scale factor for scaled address in lea instruction. */ | |
56 | static int lea_max_mul; | |
57 | ||
58 | void | |
59 | init_expmed () | |
60 | { | |
61 | char *free_point = (char *) oballoc (1); | |
62 | /* This is "some random pseudo register" for purposes of calling recog | |
63 | to see what insns exist. */ | |
64 | rtx reg = gen_rtx (REG, word_mode, FIRST_PSEUDO_REGISTER); | |
65 | rtx pow2 = gen_rtx (CONST_INT, VOIDmode, 32); | |
66 | rtx lea; | |
67 | int i, dummy; | |
68 | ||
aeedc93f | 69 | add_cost = rtx_cost (gen_rtx (PLUS, word_mode, reg, reg), SET); |
44037a66 TG |
70 | shift_cost = rtx_cost (gen_rtx (LSHIFT, word_mode, reg, |
71 | /* Using a constant gives better | |
72 | estimate of typical costs. | |
73 | 1 or 2 might have quirks. */ | |
aeedc93f RS |
74 | gen_rtx (CONST_INT, VOIDmode, 3)), SET); |
75 | mult_cost = rtx_cost (gen_rtx (MULT, word_mode, reg, reg), SET); | |
76 | negate_cost = rtx_cost (gen_rtx (NEG, word_mode, reg), SET); | |
44037a66 | 77 | |
36d747f6 | 78 | /* 999999 is chosen to avoid any plausible faster special case. */ |
44037a66 TG |
79 | mult_is_very_cheap |
80 | = (rtx_cost (gen_rtx (MULT, word_mode, reg, | |
aeedc93f | 81 | gen_rtx (CONST_INT, VOIDmode, 999999)), SET) |
44037a66 | 82 | < rtx_cost (gen_rtx (LSHIFT, word_mode, reg, |
aeedc93f | 83 | gen_rtx (CONST_INT, VOIDmode, 7)), SET)); |
44037a66 TG |
84 | |
85 | sdiv_pow2_cheap | |
aeedc93f | 86 | = rtx_cost (gen_rtx (DIV, word_mode, reg, pow2), SET) <= 2 * add_cost; |
44037a66 | 87 | smod_pow2_cheap |
aeedc93f | 88 | = rtx_cost (gen_rtx (MOD, word_mode, reg, pow2), SET) <= 2 * add_cost; |
44037a66 TG |
89 | |
90 | init_recog (); | |
91 | for (i = 2;; i <<= 1) | |
92 | { | |
93 | lea = gen_rtx (SET, VOIDmode, reg, | |
36d747f6 | 94 | gen_rtx (PLUS, word_mode, |
44037a66 | 95 | gen_rtx (MULT, word_mode, reg, |
36d747f6 RS |
96 | gen_rtx (CONST_INT, VOIDmode, i)), |
97 | reg)); | |
44037a66 TG |
98 | /* Using 0 as second argument is not quite right, |
99 | but what else is there to do? */ | |
100 | if (recog (lea, 0, &dummy) < 0) | |
101 | break; | |
102 | lea_max_mul = i; | |
aeedc93f | 103 | lea_cost = rtx_cost (SET_SRC (lea), SET); |
44037a66 TG |
104 | } |
105 | ||
106 | /* Free the objects we just allocated. */ | |
107 | obfree (free_point); | |
108 | } | |
109 | ||
110 | /* Return an rtx representing minus the value of X. | |
111 | MODE is the intended mode of the result, | |
112 | useful if X is a CONST_INT. */ | |
113 | ||
114 | rtx | |
115 | negate_rtx (mode, x) | |
116 | enum machine_mode mode; | |
117 | rtx x; | |
118 | { | |
119 | if (GET_CODE (x) == CONST_INT) | |
120 | { | |
121 | int val = - INTVAL (x); | |
122 | if (GET_MODE_BITSIZE (mode) < HOST_BITS_PER_INT) | |
123 | { | |
124 | /* Sign extend the value from the bits that are significant. */ | |
125 | if (val & (1 << (GET_MODE_BITSIZE (mode) - 1))) | |
126 | val |= (-1) << GET_MODE_BITSIZE (mode); | |
127 | else | |
128 | val &= (1 << GET_MODE_BITSIZE (mode)) - 1; | |
129 | } | |
130 | return gen_rtx (CONST_INT, VOIDmode, val); | |
131 | } | |
132 | else | |
133 | return expand_unop (GET_MODE (x), neg_optab, x, 0, 0); | |
134 | } | |
135 | \f | |
136 | /* Generate code to store value from rtx VALUE | |
137 | into a bit-field within structure STR_RTX | |
138 | containing BITSIZE bits starting at bit BITNUM. | |
139 | FIELDMODE is the machine-mode of the FIELD_DECL node for this field. | |
140 | ALIGN is the alignment that STR_RTX is known to have, measured in bytes. | |
141 | TOTAL_SIZE is the size of the structure in bytes, or -1 if varying. */ | |
142 | ||
143 | /* ??? Note that there are two different ideas here for how | |
144 | to determine the size to count bits within, for a register. | |
145 | One is BITS_PER_WORD, and the other is the size of operand 3 | |
146 | of the insv pattern. (The latter assumes that an n-bit machine | |
147 | will be able to insert bit fields up to n bits wide.) | |
148 | It isn't certain that either of these is right. | |
149 | extract_bit_field has the same quandary. */ | |
150 | ||
151 | rtx | |
152 | store_bit_field (str_rtx, bitsize, bitnum, fieldmode, value, align, total_size) | |
153 | rtx str_rtx; | |
154 | register int bitsize; | |
155 | int bitnum; | |
156 | enum machine_mode fieldmode; | |
157 | rtx value; | |
158 | int align; | |
159 | int total_size; | |
160 | { | |
161 | int unit = (GET_CODE (str_rtx) == MEM) ? BITS_PER_UNIT : BITS_PER_WORD; | |
162 | register int offset = bitnum / unit; | |
163 | register int bitpos = bitnum % unit; | |
164 | register rtx op0 = str_rtx; | |
165 | ||
166 | if (GET_CODE (str_rtx) == MEM && ! MEM_IN_STRUCT_P (str_rtx)) | |
167 | abort (); | |
168 | ||
169 | /* Discount the part of the structure before the desired byte. | |
170 | We need to know how many bytes are safe to reference after it. */ | |
171 | if (total_size >= 0) | |
172 | total_size -= (bitpos / BIGGEST_ALIGNMENT | |
173 | * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); | |
174 | ||
175 | while (GET_CODE (op0) == SUBREG) | |
176 | { | |
177 | /* The following line once was done only if WORDS_BIG_ENDIAN, | |
178 | but I think that is a mistake. WORDS_BIG_ENDIAN is | |
179 | meaningful at a much higher level; when structures are copied | |
180 | between memory and regs, the higher-numbered regs | |
181 | always get higher addresses. */ | |
182 | offset += SUBREG_WORD (op0); | |
183 | /* We used to adjust BITPOS here, but now we do the whole adjustment | |
184 | right after the loop. */ | |
185 | op0 = SUBREG_REG (op0); | |
186 | } | |
187 | ||
188 | #if BYTES_BIG_ENDIAN | |
189 | /* If OP0 is a register, BITPOS must count within a word. | |
190 | But as we have it, it counts within whatever size OP0 now has. | |
191 | On a bigendian machine, these are not the same, so convert. */ | |
192 | if (GET_CODE (op0) != MEM && unit > GET_MODE_BITSIZE (GET_MODE (op0))) | |
193 | bitpos += unit - GET_MODE_BITSIZE (GET_MODE (op0)); | |
194 | #endif | |
195 | ||
196 | value = protect_from_queue (value, 0); | |
197 | ||
198 | if (flag_force_mem) | |
199 | value = force_not_mem (value); | |
200 | ||
201 | /* Note that the adjustment of BITPOS above has no effect on whether | |
202 | BITPOS is 0 in a REG bigger than a word. */ | |
56a2f049 RS |
203 | if (GET_MODE_SIZE (fieldmode) >= UNITS_PER_WORD |
204 | && (! STRICT_ALIGNMENT || GET_CODE (op0) != MEM) | |
44037a66 TG |
205 | && bitpos == 0 && bitsize == GET_MODE_BITSIZE (fieldmode)) |
206 | { | |
207 | /* Storing in a full-word or multi-word field in a register | |
208 | can be done with just SUBREG. */ | |
209 | if (GET_MODE (op0) != fieldmode) | |
56a2f049 RS |
210 | if (GET_CODE (op0) == REG) |
211 | op0 = gen_rtx (SUBREG, fieldmode, op0, offset); | |
212 | else | |
213 | op0 = change_address (op0, fieldmode, | |
214 | plus_constant (XEXP (op0, 0), offset)); | |
44037a66 TG |
215 | emit_move_insn (op0, value); |
216 | return value; | |
217 | } | |
218 | ||
219 | /* Storing an lsb-aligned field in a register | |
220 | can be done with a movestrict instruction. */ | |
221 | ||
222 | if (GET_CODE (op0) != MEM | |
223 | #if BYTES_BIG_ENDIAN | |
224 | && bitpos + bitsize == unit | |
225 | #else | |
226 | && bitpos == 0 | |
227 | #endif | |
228 | && bitsize == GET_MODE_BITSIZE (fieldmode) | |
229 | && (GET_MODE (op0) == fieldmode | |
230 | || (movstrict_optab->handlers[(int) fieldmode].insn_code | |
231 | != CODE_FOR_nothing))) | |
232 | { | |
233 | /* Get appropriate low part of the value being stored. */ | |
234 | if (GET_CODE (value) == CONST_INT || GET_CODE (value) == REG) | |
235 | value = gen_lowpart (fieldmode, value); | |
236 | else if (!(GET_CODE (value) == SYMBOL_REF | |
237 | || GET_CODE (value) == LABEL_REF | |
238 | || GET_CODE (value) == CONST)) | |
239 | value = convert_to_mode (fieldmode, value, 0); | |
240 | ||
241 | if (GET_MODE (op0) == fieldmode) | |
242 | emit_move_insn (op0, value); | |
243 | else | |
244 | { | |
245 | int icode = movstrict_optab->handlers[(int) fieldmode].insn_code; | |
246 | if(! (*insn_operand_predicate[icode][1]) (value, fieldmode)) | |
247 | value = copy_to_mode_reg (fieldmode, value); | |
248 | emit_insn (GEN_FCN (icode) | |
249 | (gen_rtx (SUBREG, fieldmode, op0, offset), value)); | |
250 | } | |
251 | return value; | |
252 | } | |
253 | ||
254 | /* Handle fields bigger than a word. */ | |
255 | ||
256 | if (bitsize > BITS_PER_WORD) | |
257 | { | |
258 | /* Here we transfer the words of the field | |
259 | in the order least significant first. | |
260 | This is because the most significant word is the one which may | |
261 | be less than full. */ | |
262 | ||
263 | int nwords = (bitsize + (BITS_PER_WORD - 1)) / BITS_PER_WORD; | |
264 | int i; | |
265 | ||
266 | /* This is the mode we must force value to, so that there will be enough | |
267 | subwords to extract. Note that fieldmode will often (always?) be | |
268 | VOIDmode, because that is what store_field uses to indicate that this | |
269 | is a bit field, but passing VOIDmode to operand_subword_force will | |
270 | result in an abort. */ | |
271 | fieldmode = mode_for_size (nwords * BITS_PER_WORD, MODE_INT, 0); | |
272 | ||
273 | for (i = 0; i < nwords; i++) | |
274 | { | |
275 | /* If I is 0, use the low-order word in both field and target; | |
276 | if I is 1, use the next to lowest word; and so on. */ | |
277 | int wordnum = (WORDS_BIG_ENDIAN ? nwords - i - 1 : i); | |
278 | int bit_offset = (WORDS_BIG_ENDIAN | |
279 | ? MAX (bitsize - (i + 1) * BITS_PER_WORD, 0) | |
280 | : i * BITS_PER_WORD); | |
281 | store_bit_field (op0, MIN (BITS_PER_WORD, | |
282 | bitsize - i * BITS_PER_WORD), | |
283 | bitnum + bit_offset, word_mode, | |
284 | operand_subword_force (value, wordnum, fieldmode), | |
285 | align, total_size); | |
286 | } | |
287 | return value; | |
288 | } | |
289 | ||
290 | /* From here on we can assume that the field to be stored in is | |
291 | a full-word (whatever type that is), since it is shorter than a word. */ | |
292 | ||
293 | /* OFFSET is the number of words or bytes (UNIT says which) | |
294 | from STR_RTX to the first word or byte containing part of the field. */ | |
295 | ||
296 | if (GET_CODE (op0) == REG) | |
297 | { | |
298 | if (offset != 0 | |
299 | || GET_MODE_SIZE (GET_MODE (op0)) > UNITS_PER_WORD) | |
300 | op0 = gen_rtx (SUBREG, TYPE_MODE (type_for_size (BITS_PER_WORD, 0)), | |
301 | op0, offset); | |
302 | offset = 0; | |
303 | } | |
304 | else | |
305 | { | |
306 | op0 = protect_from_queue (op0, 1); | |
307 | } | |
308 | ||
309 | /* Now OFFSET is nonzero only if OP0 is memory | |
310 | and is therefore always measured in bytes. */ | |
311 | ||
312 | #ifdef HAVE_insv | |
313 | if (HAVE_insv | |
314 | && !(bitsize == 1 && GET_CODE (value) == CONST_INT) | |
315 | /* Ensure insv's size is wide enough for this field. */ | |
316 | && (GET_MODE_BITSIZE (insn_operand_mode[(int) CODE_FOR_insv][3]) | |
317 | >= bitsize)) | |
318 | { | |
319 | int xbitpos = bitpos; | |
320 | rtx value1; | |
321 | rtx xop0 = op0; | |
322 | rtx last = get_last_insn (); | |
323 | rtx pat; | |
324 | enum machine_mode maxmode | |
325 | = insn_operand_mode[(int) CODE_FOR_insv][3]; | |
326 | ||
327 | int save_volatile_ok = volatile_ok; | |
328 | volatile_ok = 1; | |
329 | ||
330 | /* If this machine's insv can only insert into a register, or if we | |
331 | are to force MEMs into a register, copy OP0 into a register and | |
332 | save it back later. */ | |
333 | if (GET_CODE (op0) == MEM | |
334 | && (flag_force_mem | |
335 | || ! ((*insn_operand_predicate[(int) CODE_FOR_insv][0]) | |
336 | (op0, VOIDmode)))) | |
337 | { | |
338 | rtx tempreg; | |
339 | enum machine_mode bestmode; | |
340 | ||
341 | /* Get the mode to use for inserting into this field. If OP0 is | |
342 | BLKmode, get the smallest mode consistent with the alignment. If | |
343 | OP0 is a non-BLKmode object that is no wider than MAXMODE, use its | |
344 | mode. Otherwise, use the smallest mode containing the field. */ | |
345 | ||
346 | if (GET_MODE (op0) == BLKmode | |
347 | || GET_MODE_SIZE (GET_MODE (op0)) > GET_MODE_SIZE (maxmode)) | |
348 | bestmode | |
717702e6 RK |
349 | = get_best_mode (bitsize, bitnum, align * BITS_PER_UNIT, maxmode, |
350 | MEM_VOLATILE_P (op0)); | |
44037a66 TG |
351 | else |
352 | bestmode = GET_MODE (op0); | |
353 | ||
354 | if (bestmode == VOIDmode) | |
355 | goto insv_loses; | |
356 | ||
357 | /* Adjust address to point to the containing unit of that mode. */ | |
358 | unit = GET_MODE_BITSIZE (bestmode); | |
359 | /* Compute offset as multiple of this unit, counting in bytes. */ | |
360 | offset = (bitnum / unit) * GET_MODE_SIZE (bestmode); | |
361 | bitpos = bitnum % unit; | |
362 | op0 = change_address (op0, bestmode, | |
363 | plus_constant (XEXP (op0, 0), offset)); | |
364 | ||
365 | /* Fetch that unit, store the bitfield in it, then store the unit. */ | |
366 | tempreg = copy_to_reg (op0); | |
367 | store_bit_field (tempreg, bitsize, bitpos, fieldmode, value, | |
368 | align, total_size); | |
369 | emit_move_insn (op0, tempreg); | |
370 | return value; | |
371 | } | |
372 | volatile_ok = save_volatile_ok; | |
373 | ||
374 | /* Add OFFSET into OP0's address. */ | |
375 | if (GET_CODE (xop0) == MEM) | |
376 | xop0 = change_address (xop0, byte_mode, | |
377 | plus_constant (XEXP (xop0, 0), offset)); | |
378 | ||
379 | /* If xop0 is a register, we need it in MAXMODE | |
380 | to make it acceptable to the format of insv. */ | |
381 | if (GET_CODE (xop0) == SUBREG) | |
382 | PUT_MODE (xop0, maxmode); | |
383 | if (GET_CODE (xop0) == REG && GET_MODE (xop0) != maxmode) | |
384 | xop0 = gen_rtx (SUBREG, maxmode, xop0, 0); | |
385 | ||
386 | /* On big-endian machines, we count bits from the most significant. | |
387 | If the bit field insn does not, we must invert. */ | |
388 | ||
389 | #if BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN | |
390 | xbitpos = unit - bitsize - xbitpos; | |
391 | #endif | |
392 | /* We have been counting XBITPOS within UNIT. | |
393 | Count instead within the size of the register. */ | |
394 | #if BITS_BIG_ENDIAN | |
395 | if (GET_CODE (xop0) != MEM) | |
396 | xbitpos += GET_MODE_BITSIZE (maxmode) - unit; | |
397 | #endif | |
398 | unit = GET_MODE_BITSIZE (maxmode); | |
399 | ||
400 | /* Convert VALUE to maxmode (which insv insn wants) in VALUE1. */ | |
401 | value1 = value; | |
402 | if (GET_MODE (value) != maxmode) | |
403 | { | |
404 | if (GET_MODE_BITSIZE (GET_MODE (value)) >= bitsize) | |
405 | { | |
406 | /* Optimization: Don't bother really extending VALUE | |
407 | if it has all the bits we will actually use. */ | |
408 | ||
409 | /* Avoid making subreg of a subreg, or of a mem. */ | |
410 | if (GET_CODE (value1) != REG) | |
411 | value1 = copy_to_reg (value1); | |
412 | value1 = gen_rtx (SUBREG, maxmode, value1, 0); | |
413 | } | |
414 | else if (!CONSTANT_P (value)) | |
415 | /* Parse phase is supposed to make VALUE's data type | |
416 | match that of the component reference, which is a type | |
417 | at least as wide as the field; so VALUE should have | |
418 | a mode that corresponds to that type. */ | |
419 | abort (); | |
420 | } | |
421 | ||
422 | /* If this machine's insv insists on a register, | |
423 | get VALUE1 into a register. */ | |
424 | if (! ((*insn_operand_predicate[(int) CODE_FOR_insv][3]) | |
425 | (value1, maxmode))) | |
426 | value1 = force_reg (maxmode, value1); | |
427 | ||
428 | pat = gen_insv (xop0, | |
429 | gen_rtx (CONST_INT, VOIDmode, bitsize), | |
430 | gen_rtx (CONST_INT, VOIDmode, xbitpos), | |
431 | value1); | |
432 | if (pat) | |
433 | emit_insn (pat); | |
434 | else | |
435 | { | |
436 | delete_insns_since (last); | |
437 | store_fixed_bit_field (op0, offset, bitsize, bitpos, value, align); | |
438 | } | |
439 | } | |
440 | else | |
441 | insv_loses: | |
442 | #endif | |
443 | /* Insv is not available; store using shifts and boolean ops. */ | |
444 | store_fixed_bit_field (op0, offset, bitsize, bitpos, value, align); | |
445 | return value; | |
446 | } | |
447 | \f | |
448 | /* Use shifts and boolean operations to store VALUE | |
449 | into a bit field of width BITSIZE | |
450 | in a memory location specified by OP0 except offset by OFFSET bytes. | |
451 | (OFFSET must be 0 if OP0 is a register.) | |
452 | The field starts at position BITPOS within the byte. | |
453 | (If OP0 is a register, it may be a full word or a narrower mode, | |
454 | but BITPOS still counts within a full word, | |
455 | which is significant on bigendian machines.) | |
456 | STRUCT_ALIGN is the alignment the structure is known to have (in bytes). | |
457 | ||
458 | Note that protect_from_queue has already been done on OP0 and VALUE. */ | |
459 | ||
460 | static void | |
461 | store_fixed_bit_field (op0, offset, bitsize, bitpos, value, struct_align) | |
462 | register rtx op0; | |
463 | register int offset, bitsize, bitpos; | |
464 | register rtx value; | |
465 | int struct_align; | |
466 | { | |
467 | register enum machine_mode mode; | |
468 | int total_bits = BITS_PER_WORD; | |
469 | rtx subtarget, temp; | |
470 | int all_zero = 0; | |
471 | int all_one = 0; | |
472 | ||
473 | /* Add OFFSET to OP0's address (if it is in memory) | |
474 | and if a single byte contains the whole bit field | |
475 | change OP0 to a byte. */ | |
476 | ||
477 | /* There is a case not handled here: | |
478 | a structure with a known alignment of just a halfword | |
479 | and a field split across two aligned halfwords within the structure. | |
480 | Or likewise a structure with a known alignment of just a byte | |
481 | and a field split across two bytes. | |
482 | Such cases are not supposed to be able to occur. */ | |
483 | ||
484 | if (GET_CODE (op0) == REG || GET_CODE (op0) == SUBREG) | |
485 | { | |
486 | if (offset != 0) | |
487 | abort (); | |
488 | /* Special treatment for a bit field split across two registers. */ | |
489 | if (bitsize + bitpos > BITS_PER_WORD) | |
490 | { | |
491 | store_split_bit_field (op0, bitsize, bitpos, value, BITS_PER_WORD); | |
492 | return; | |
493 | } | |
494 | } | |
495 | else | |
496 | { | |
497 | /* Get the proper mode to use for this field. We want a mode that | |
498 | includes the entire field. If such a mode would be larger than | |
499 | a word, we won't be doing the extraction the normal way. */ | |
500 | ||
501 | mode = get_best_mode (bitsize, bitpos + offset * BITS_PER_UNIT, | |
502 | struct_align * BITS_PER_UNIT, word_mode, | |
503 | GET_CODE (op0) == MEM && MEM_VOLATILE_P (op0)); | |
504 | ||
505 | if (mode == VOIDmode) | |
506 | { | |
507 | /* The only way this should occur is if the field spans word | |
508 | boundaries. */ | |
509 | store_split_bit_field (op0, bitsize, bitpos + offset * BITS_PER_UNIT, | |
510 | value, struct_align); | |
511 | return; | |
512 | } | |
513 | ||
514 | total_bits = GET_MODE_BITSIZE (mode); | |
515 | ||
516 | /* Get ref to an aligned byte, halfword, or word containing the field. | |
517 | Adjust BITPOS to be position within a word, | |
518 | and OFFSET to be the offset of that word. | |
519 | Then alter OP0 to refer to that word. */ | |
520 | bitpos += (offset % (total_bits / BITS_PER_UNIT)) * BITS_PER_UNIT; | |
521 | offset -= (offset % (total_bits / BITS_PER_UNIT)); | |
522 | op0 = change_address (op0, mode, | |
523 | plus_constant (XEXP (op0, 0), offset)); | |
524 | } | |
525 | ||
526 | mode = GET_MODE (op0); | |
527 | ||
528 | /* Now MODE is either some integral mode for a MEM as OP0, | |
529 | or is a full-word for a REG as OP0. TOTAL_BITS corresponds. | |
530 | The bit field is contained entirely within OP0. | |
531 | BITPOS is the starting bit number within OP0. | |
532 | (OP0's mode may actually be narrower than MODE.) */ | |
533 | ||
534 | #if BYTES_BIG_ENDIAN | |
535 | /* BITPOS is the distance between our msb | |
536 | and that of the containing datum. | |
537 | Convert it to the distance from the lsb. */ | |
538 | ||
539 | bitpos = total_bits - bitsize - bitpos; | |
540 | #endif | |
541 | /* Now BITPOS is always the distance between our lsb | |
542 | and that of OP0. */ | |
543 | ||
544 | /* Shift VALUE left by BITPOS bits. If VALUE is not constant, | |
545 | we must first convert its mode to MODE. */ | |
546 | ||
547 | if (GET_CODE (value) == CONST_INT) | |
548 | { | |
549 | register int v = INTVAL (value); | |
550 | ||
551 | if (bitsize < HOST_BITS_PER_INT) | |
552 | v &= (1 << bitsize) - 1; | |
553 | ||
554 | if (v == 0) | |
555 | all_zero = 1; | |
556 | else if ((bitsize < HOST_BITS_PER_INT && v == (1 << bitsize) - 1) | |
557 | || (bitsize == HOST_BITS_PER_INT && v == -1)) | |
558 | all_one = 1; | |
559 | ||
560 | value = lshift_value (mode, value, bitpos, bitsize); | |
561 | } | |
562 | else | |
563 | { | |
564 | int must_and = (GET_MODE_BITSIZE (GET_MODE (value)) != bitsize | |
565 | && bitpos + bitsize != GET_MODE_BITSIZE (mode)); | |
566 | ||
567 | if (GET_MODE (value) != mode) | |
568 | { | |
569 | /* If VALUE is a floating-point mode, access it as an integer | |
570 | of the corresponding size, then convert it. This can occur on | |
571 | a machine with 64 bit registers that uses SFmode for float. */ | |
572 | if (GET_MODE_CLASS (GET_MODE (value)) == MODE_FLOAT) | |
573 | { | |
574 | if (GET_CODE (value) != REG) | |
575 | value = copy_to_reg (value); | |
576 | value | |
577 | = gen_rtx (SUBREG, word_mode, value, 0); | |
578 | } | |
579 | ||
580 | if ((GET_CODE (value) == REG || GET_CODE (value) == SUBREG) | |
581 | && GET_MODE_SIZE (mode) < GET_MODE_SIZE (GET_MODE (value))) | |
582 | value = gen_lowpart (mode, value); | |
583 | else | |
584 | value = convert_to_mode (mode, value, 1); | |
585 | } | |
586 | ||
587 | if (must_and) | |
588 | value = expand_binop (mode, and_optab, value, | |
589 | mask_rtx (mode, 0, bitsize, 0), | |
590 | 0, 1, OPTAB_LIB_WIDEN); | |
591 | if (bitpos > 0) | |
592 | value = expand_shift (LSHIFT_EXPR, mode, value, | |
593 | build_int_2 (bitpos, 0), 0, 1); | |
594 | } | |
595 | ||
596 | /* Now clear the chosen bits in OP0, | |
597 | except that if VALUE is -1 we need not bother. */ | |
598 | ||
599 | subtarget = (GET_CODE (op0) == REG || ! flag_force_mem) ? op0 : 0; | |
600 | ||
601 | if (! all_one) | |
602 | { | |
603 | temp = expand_binop (mode, and_optab, op0, | |
604 | mask_rtx (mode, bitpos, bitsize, 1), | |
605 | subtarget, 1, OPTAB_LIB_WIDEN); | |
606 | subtarget = temp; | |
607 | } | |
608 | else | |
609 | temp = op0; | |
610 | ||
611 | /* Now logical-or VALUE into OP0, unless it is zero. */ | |
612 | ||
613 | if (! all_zero) | |
614 | temp = expand_binop (mode, ior_optab, temp, value, | |
615 | subtarget, 1, OPTAB_LIB_WIDEN); | |
616 | if (op0 != temp) | |
617 | emit_move_insn (op0, temp); | |
618 | } | |
619 | \f | |
620 | /* Store a bit field that is split across two words. | |
621 | ||
622 | OP0 is the REG, SUBREG or MEM rtx for the first of the two words. | |
623 | BITSIZE is the field width; BITPOS the position of its first bit | |
624 | (within the word). | |
625 | VALUE is the value to store. */ | |
626 | ||
627 | static void | |
628 | store_split_bit_field (op0, bitsize, bitpos, value, align) | |
629 | rtx op0; | |
630 | int bitsize, bitpos; | |
631 | rtx value; | |
632 | int align; | |
633 | { | |
634 | /* BITSIZE_1 is size of the part in the first word. */ | |
635 | int bitsize_1 = BITS_PER_WORD - bitpos % BITS_PER_WORD; | |
636 | /* BITSIZE_2 is size of the rest (in the following word). */ | |
637 | int bitsize_2 = bitsize - bitsize_1; | |
638 | rtx part1, part2; | |
639 | int unit = GET_CODE (op0) == MEM ? BITS_PER_UNIT : BITS_PER_WORD; | |
640 | int offset = bitpos / unit; | |
641 | rtx word; | |
642 | ||
643 | /* The field must span exactly one word boundary. */ | |
644 | if (bitpos / BITS_PER_WORD != (bitpos + bitsize - 1) / BITS_PER_WORD - 1) | |
645 | abort (); | |
646 | ||
647 | if (GET_MODE (value) != VOIDmode) | |
648 | value = convert_to_mode (word_mode, value, 1); | |
649 | if (CONSTANT_P (value) && GET_CODE (value) != CONST_INT) | |
650 | value = copy_to_reg (value); | |
651 | ||
652 | /* Split the value into two parts: | |
653 | PART1 gets that which goes in the first word; PART2 the other. */ | |
654 | #if BYTES_BIG_ENDIAN | |
655 | /* PART1 gets the more significant part. */ | |
656 | if (GET_CODE (value) == CONST_INT) | |
657 | { | |
658 | part1 = gen_rtx (CONST_INT, VOIDmode, | |
659 | (unsigned) (INTVAL (value)) >> bitsize_2); | |
660 | part2 = gen_rtx (CONST_INT, VOIDmode, | |
661 | (unsigned) (INTVAL (value)) & ((1 << bitsize_2) - 1)); | |
662 | } | |
663 | else | |
664 | { | |
665 | part1 = extract_fixed_bit_field (word_mode, value, 0, bitsize_1, | |
666 | BITS_PER_WORD - bitsize, 0, 1, | |
667 | BITS_PER_WORD); | |
668 | part2 = extract_fixed_bit_field (word_mode, value, 0, bitsize_2, | |
669 | BITS_PER_WORD - bitsize_2, 0, 1, | |
670 | BITS_PER_WORD); | |
671 | } | |
672 | #else | |
673 | /* PART1 gets the less significant part. */ | |
674 | if (GET_CODE (value) == CONST_INT) | |
675 | { | |
676 | part1 = gen_rtx (CONST_INT, VOIDmode, | |
677 | (unsigned) (INTVAL (value)) & ((1 << bitsize_1) - 1)); | |
678 | part2 = gen_rtx (CONST_INT, VOIDmode, | |
679 | (unsigned) (INTVAL (value)) >> bitsize_1); | |
680 | } | |
681 | else | |
682 | { | |
683 | part1 = extract_fixed_bit_field (word_mode, value, 0, bitsize_1, 0, | |
684 | 0, 1, BITS_PER_WORD); | |
685 | part2 = extract_fixed_bit_field (word_mode, value, 0, bitsize_2, | |
686 | bitsize_1, 0, 1, BITS_PER_WORD); | |
687 | } | |
688 | #endif | |
689 | ||
690 | /* Store PART1 into the first word. If OP0 is a MEM, pass OP0 and the | |
691 | offset computed above. Otherwise, get the proper word and pass an | |
692 | offset of zero. */ | |
693 | word = (GET_CODE (op0) == MEM ? op0 | |
694 | : operand_subword (op0, offset, 1, GET_MODE (op0))); | |
695 | if (word == 0) | |
696 | abort (); | |
697 | ||
698 | store_fixed_bit_field (word, GET_CODE (op0) == MEM ? offset : 0, | |
699 | bitsize_1, bitpos % unit, part1, align); | |
700 | ||
701 | /* Offset op0 by 1 word to get to the following one. */ | |
702 | if (GET_CODE (op0) == SUBREG) | |
703 | word = operand_subword (SUBREG_REG (op0), SUBREG_WORD (op0) + offset + 1, | |
704 | 1, VOIDmode); | |
705 | else if (GET_CODE (op0) == MEM) | |
706 | word = op0; | |
707 | else | |
708 | word = operand_subword (op0, offset + 1, 1, GET_MODE (op0)); | |
709 | ||
710 | if (word == 0) | |
711 | abort (); | |
712 | ||
713 | /* Store PART2 into the second word. */ | |
714 | store_fixed_bit_field (word, | |
715 | (GET_CODE (op0) == MEM | |
716 | ? CEIL (offset + 1, UNITS_PER_WORD) * UNITS_PER_WORD | |
717 | : 0), | |
718 | bitsize_2, 0, part2, align); | |
719 | } | |
720 | \f | |
721 | /* Generate code to extract a byte-field from STR_RTX | |
722 | containing BITSIZE bits, starting at BITNUM, | |
723 | and put it in TARGET if possible (if TARGET is nonzero). | |
724 | Regardless of TARGET, we return the rtx for where the value is placed. | |
725 | It may be a QUEUED. | |
726 | ||
727 | STR_RTX is the structure containing the byte (a REG or MEM). | |
728 | UNSIGNEDP is nonzero if this is an unsigned bit field. | |
729 | MODE is the natural mode of the field value once extracted. | |
730 | TMODE is the mode the caller would like the value to have; | |
731 | but the value may be returned with type MODE instead. | |
732 | ||
733 | ALIGN is the alignment that STR_RTX is known to have, measured in bytes. | |
734 | TOTAL_SIZE is the size in bytes of the containing structure, | |
735 | or -1 if varying. | |
736 | ||
737 | If a TARGET is specified and we can store in it at no extra cost, | |
738 | we do so, and return TARGET. | |
739 | Otherwise, we return a REG of mode TMODE or MODE, with TMODE preferred | |
740 | if they are equally easy. */ | |
741 | ||
742 | rtx | |
743 | extract_bit_field (str_rtx, bitsize, bitnum, unsignedp, | |
744 | target, mode, tmode, align, total_size) | |
745 | rtx str_rtx; | |
746 | register int bitsize; | |
747 | int bitnum; | |
748 | int unsignedp; | |
749 | rtx target; | |
750 | enum machine_mode mode, tmode; | |
751 | int align; | |
752 | int total_size; | |
753 | { | |
754 | int unit = (GET_CODE (str_rtx) == MEM) ? BITS_PER_UNIT : BITS_PER_WORD; | |
755 | register int offset = bitnum / unit; | |
756 | register int bitpos = bitnum % unit; | |
757 | register rtx op0 = str_rtx; | |
758 | rtx spec_target = target; | |
759 | rtx spec_target_subreg = 0; | |
760 | ||
761 | if (GET_CODE (str_rtx) == MEM && ! MEM_IN_STRUCT_P (str_rtx)) | |
762 | abort (); | |
763 | ||
764 | /* Discount the part of the structure before the desired byte. | |
765 | We need to know how many bytes are safe to reference after it. */ | |
766 | if (total_size >= 0) | |
767 | total_size -= (bitpos / BIGGEST_ALIGNMENT | |
768 | * (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); | |
769 | ||
770 | if (tmode == VOIDmode) | |
771 | tmode = mode; | |
772 | ||
773 | while (GET_CODE (op0) == SUBREG) | |
774 | { | |
775 | offset += SUBREG_WORD (op0); | |
776 | op0 = SUBREG_REG (op0); | |
777 | } | |
778 | ||
779 | #if BYTES_BIG_ENDIAN | |
780 | /* If OP0 is a register, BITPOS must count within a word. | |
781 | But as we have it, it counts within whatever size OP0 now has. | |
782 | On a bigendian machine, these are not the same, so convert. */ | |
783 | if (GET_CODE (op0) != MEM && unit > GET_MODE_BITSIZE (GET_MODE (op0))) | |
784 | bitpos += unit - GET_MODE_BITSIZE (GET_MODE (op0)); | |
785 | #endif | |
786 | ||
787 | /* Extracting a full-word or multi-word value | |
788 | from a structure in a register. | |
789 | This can be done with just SUBREG. | |
790 | So too extracting a subword value in | |
791 | the least significant part of the register. */ | |
792 | ||
793 | if (GET_CODE (op0) == REG | |
794 | && ((bitsize >= BITS_PER_WORD && bitsize == GET_MODE_BITSIZE (mode) | |
795 | && bitpos % BITS_PER_WORD == 0) | |
796 | || (mode_for_size (bitsize, GET_MODE_CLASS (tmode), 0) != BLKmode | |
797 | #if BYTES_BIG_ENDIAN | |
798 | && bitpos + bitsize == BITS_PER_WORD | |
799 | #else | |
800 | && bitpos == 0 | |
801 | #endif | |
802 | ))) | |
803 | { | |
804 | enum machine_mode mode1 | |
805 | = mode_for_size (bitsize, GET_MODE_CLASS (tmode), 0); | |
806 | ||
807 | if (mode1 != GET_MODE (op0)) | |
808 | op0 = gen_rtx (SUBREG, mode1, op0, offset); | |
809 | ||
810 | if (mode1 != mode) | |
811 | return convert_to_mode (tmode, op0, unsignedp); | |
812 | return op0; | |
813 | } | |
814 | ||
815 | /* Handle fields bigger than a word. */ | |
816 | ||
817 | if (bitsize > BITS_PER_WORD) | |
818 | { | |
819 | /* Here we transfer the words of the field | |
820 | in the order least significant first. | |
821 | This is because the most significant word is the one which may | |
822 | be less than full. */ | |
823 | ||
824 | int nwords = (bitsize + (BITS_PER_WORD - 1)) / BITS_PER_WORD; | |
825 | int i; | |
826 | ||
827 | if (target == 0 || GET_CODE (target) != REG) | |
828 | target = gen_reg_rtx (mode); | |
829 | ||
830 | for (i = 0; i < nwords; i++) | |
831 | { | |
832 | /* If I is 0, use the low-order word in both field and target; | |
833 | if I is 1, use the next to lowest word; and so on. */ | |
834 | int wordnum = (WORDS_BIG_ENDIAN ? nwords - i - 1 : i); | |
835 | int bit_offset = (WORDS_BIG_ENDIAN | |
836 | ? MAX (0, bitsize - (i + 1) * BITS_PER_WORD) | |
837 | : i * BITS_PER_WORD); | |
838 | rtx target_part = operand_subword (target, wordnum, 1, VOIDmode); | |
839 | rtx result_part | |
840 | = extract_bit_field (op0, MIN (BITS_PER_WORD, | |
841 | bitsize - i * BITS_PER_WORD), | |
842 | bitnum + bit_offset, | |
843 | 1, target_part, mode, word_mode, | |
844 | align, total_size); | |
845 | ||
846 | if (target_part == 0) | |
847 | abort (); | |
848 | ||
849 | if (result_part != target_part) | |
850 | emit_move_insn (target_part, result_part); | |
851 | } | |
852 | ||
853 | return target; | |
854 | } | |
855 | ||
856 | /* From here on we know the desired field is smaller than a word | |
857 | so we can assume it is an integer. So we can safely extract it as one | |
858 | size of integer, if necessary, and then truncate or extend | |
859 | to the size that is wanted. */ | |
860 | ||
861 | /* OFFSET is the number of words or bytes (UNIT says which) | |
862 | from STR_RTX to the first word or byte containing part of the field. */ | |
863 | ||
864 | if (GET_CODE (op0) == REG) | |
865 | { | |
866 | if (offset != 0 | |
867 | || GET_MODE_SIZE (GET_MODE (op0)) > UNITS_PER_WORD) | |
868 | op0 = gen_rtx (SUBREG, TYPE_MODE (type_for_size (BITS_PER_WORD, 0)), | |
869 | op0, offset); | |
870 | offset = 0; | |
871 | } | |
872 | else | |
873 | { | |
874 | op0 = protect_from_queue (str_rtx, 1); | |
875 | } | |
876 | ||
877 | /* Now OFFSET is nonzero only for memory operands. */ | |
878 | ||
879 | if (unsignedp) | |
880 | { | |
881 | #ifdef HAVE_extzv | |
882 | if (HAVE_extzv | |
883 | && (GET_MODE_BITSIZE (insn_operand_mode[(int) CODE_FOR_extzv][0]) | |
884 | >= bitsize)) | |
885 | { | |
886 | int xbitpos = bitpos, xoffset = offset; | |
887 | rtx bitsize_rtx, bitpos_rtx; | |
888 | rtx last = get_last_insn(); | |
889 | rtx xop0 = op0; | |
890 | rtx xtarget = target; | |
891 | rtx xspec_target = spec_target; | |
892 | rtx xspec_target_subreg = spec_target_subreg; | |
893 | rtx pat; | |
894 | enum machine_mode maxmode | |
895 | = insn_operand_mode[(int) CODE_FOR_extzv][0]; | |
896 | ||
897 | if (GET_CODE (xop0) == MEM) | |
898 | { | |
899 | int save_volatile_ok = volatile_ok; | |
900 | volatile_ok = 1; | |
901 | ||
902 | /* Is the memory operand acceptable? */ | |
903 | if (flag_force_mem | |
904 | || ! ((*insn_operand_predicate[(int) CODE_FOR_extzv][1]) | |
905 | (xop0, GET_MODE (xop0)))) | |
906 | { | |
907 | /* No, load into a reg and extract from there. */ | |
908 | enum machine_mode bestmode; | |
909 | ||
910 | /* Get the mode to use for inserting into this field. If | |
911 | OP0 is BLKmode, get the smallest mode consistent with the | |
912 | alignment. If OP0 is a non-BLKmode object that is no | |
913 | wider than MAXMODE, use its mode. Otherwise, use the | |
914 | smallest mode containing the field. */ | |
915 | ||
916 | if (GET_MODE (xop0) == BLKmode | |
917 | || (GET_MODE_SIZE (GET_MODE (op0)) | |
918 | > GET_MODE_SIZE (maxmode))) | |
919 | bestmode = get_best_mode (bitsize, bitnum, | |
920 | align * BITS_PER_UNIT, maxmode, | |
717702e6 | 921 | MEM_VOLATILE_P (xop0)); |
44037a66 TG |
922 | else |
923 | bestmode = GET_MODE (xop0); | |
924 | ||
925 | if (bestmode == VOIDmode) | |
926 | goto extzv_loses; | |
927 | ||
928 | /* Compute offset as multiple of this unit, | |
929 | counting in bytes. */ | |
930 | unit = GET_MODE_BITSIZE (bestmode); | |
931 | xoffset = (bitnum / unit) * GET_MODE_SIZE (bestmode); | |
932 | xbitpos = bitnum % unit; | |
933 | xop0 = change_address (xop0, bestmode, | |
934 | plus_constant (XEXP (xop0, 0), | |
935 | xoffset)); | |
936 | /* Fetch it to a register in that size. */ | |
937 | xop0 = force_reg (bestmode, xop0); | |
938 | ||
939 | /* XBITPOS counts within UNIT, which is what is expected. */ | |
940 | } | |
941 | else | |
942 | /* Get ref to first byte containing part of the field. */ | |
943 | xop0 = change_address (xop0, byte_mode, | |
944 | plus_constant (XEXP (xop0, 0), xoffset)); | |
945 | ||
946 | volatile_ok = save_volatile_ok; | |
947 | } | |
948 | ||
949 | /* If op0 is a register, we need it in MAXMODE (which is usually | |
950 | SImode). to make it acceptable to the format of extzv. */ | |
951 | if (GET_CODE (xop0) == SUBREG && GET_MODE (xop0) != maxmode) | |
952 | abort (); | |
953 | if (GET_CODE (xop0) == REG && GET_MODE (xop0) != maxmode) | |
954 | xop0 = gen_rtx (SUBREG, maxmode, xop0, 0); | |
955 | ||
956 | /* On big-endian machines, we count bits from the most significant. | |
957 | If the bit field insn does not, we must invert. */ | |
958 | #if BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN | |
959 | xbitpos = unit - bitsize - xbitpos; | |
960 | #endif | |
961 | /* Now convert from counting within UNIT to counting in MAXMODE. */ | |
962 | #if BITS_BIG_ENDIAN | |
963 | if (GET_CODE (xop0) != MEM) | |
964 | xbitpos += GET_MODE_BITSIZE (maxmode) - unit; | |
965 | #endif | |
966 | unit = GET_MODE_BITSIZE (maxmode); | |
967 | ||
968 | if (xtarget == 0 | |
969 | || (flag_force_mem && GET_CODE (xtarget) == MEM)) | |
970 | xtarget = xspec_target = gen_reg_rtx (tmode); | |
971 | ||
972 | if (GET_MODE (xtarget) != maxmode) | |
973 | { | |
974 | if (GET_CODE (xtarget) == REG) | |
b7a09135 RS |
975 | { |
976 | int wider = (GET_MODE_SIZE (maxmode) | |
977 | > GET_MODE_SIZE (GET_MODE (xtarget))); | |
978 | xtarget = gen_lowpart (maxmode, xtarget); | |
979 | if (wider) | |
980 | xspec_target_subreg = xtarget; | |
981 | } | |
44037a66 TG |
982 | else |
983 | xtarget = gen_reg_rtx (maxmode); | |
984 | } | |
985 | ||
986 | /* If this machine's extzv insists on a register target, | |
987 | make sure we have one. */ | |
988 | if (! ((*insn_operand_predicate[(int) CODE_FOR_extzv][0]) | |
989 | (xtarget, maxmode))) | |
990 | xtarget = gen_reg_rtx (maxmode); | |
991 | ||
992 | bitsize_rtx = gen_rtx (CONST_INT, VOIDmode, bitsize); | |
993 | bitpos_rtx = gen_rtx (CONST_INT, VOIDmode, xbitpos); | |
994 | ||
995 | pat = gen_extzv (protect_from_queue (xtarget, 1), | |
996 | xop0, bitsize_rtx, bitpos_rtx); | |
997 | if (pat) | |
998 | { | |
999 | emit_insn (pat); | |
1000 | target = xtarget; | |
1001 | spec_target = xspec_target; | |
1002 | spec_target_subreg = xspec_target_subreg; | |
1003 | } | |
1004 | else | |
1005 | { | |
1006 | delete_insns_since (last); | |
1007 | target = extract_fixed_bit_field (tmode, op0, offset, bitsize, | |
1008 | bitpos, target, 1, align); | |
1009 | } | |
1010 | } | |
1011 | else | |
1012 | extzv_loses: | |
1013 | #endif | |
1014 | target = extract_fixed_bit_field (tmode, op0, offset, bitsize, bitpos, | |
1015 | target, 1, align); | |
1016 | } | |
1017 | else | |
1018 | { | |
1019 | #ifdef HAVE_extv | |
1020 | if (HAVE_extv | |
1021 | && (GET_MODE_BITSIZE (insn_operand_mode[(int) CODE_FOR_extv][0]) | |
1022 | >= bitsize)) | |
1023 | { | |
1024 | int xbitpos = bitpos, xoffset = offset; | |
1025 | rtx bitsize_rtx, bitpos_rtx; | |
1026 | rtx last = get_last_insn(); | |
1027 | rtx xop0 = op0, xtarget = target; | |
1028 | rtx xspec_target = spec_target; | |
1029 | rtx xspec_target_subreg = spec_target_subreg; | |
1030 | rtx pat; | |
1031 | enum machine_mode maxmode | |
1032 | = insn_operand_mode[(int) CODE_FOR_extv][0]; | |
1033 | ||
1034 | if (GET_CODE (xop0) == MEM) | |
1035 | { | |
1036 | /* Is the memory operand acceptable? */ | |
1037 | if (! ((*insn_operand_predicate[(int) CODE_FOR_extv][1]) | |
1038 | (xop0, GET_MODE (xop0)))) | |
1039 | { | |
1040 | /* No, load into a reg and extract from there. */ | |
1041 | enum machine_mode bestmode; | |
1042 | ||
1043 | /* Get the mode to use for inserting into this field. If | |
1044 | OP0 is BLKmode, get the smallest mode consistent with the | |
1045 | alignment. If OP0 is a non-BLKmode object that is no | |
1046 | wider than MAXMODE, use its mode. Otherwise, use the | |
1047 | smallest mode containing the field. */ | |
1048 | ||
1049 | if (GET_MODE (xop0) == BLKmode | |
1050 | || (GET_MODE_SIZE (GET_MODE (op0)) | |
1051 | > GET_MODE_SIZE (maxmode))) | |
1052 | bestmode = get_best_mode (bitsize, bitnum, | |
1053 | align * BITS_PER_UNIT, maxmode, | |
717702e6 | 1054 | MEM_VOLATILE_P (xop0)); |
44037a66 TG |
1055 | else |
1056 | bestmode = GET_MODE (xop0); | |
1057 | ||
1058 | if (bestmode == VOIDmode) | |
1059 | goto extv_loses; | |
1060 | ||
1061 | /* Compute offset as multiple of this unit, | |
1062 | counting in bytes. */ | |
1063 | unit = GET_MODE_BITSIZE (bestmode); | |
1064 | xoffset = (bitnum / unit) * GET_MODE_SIZE (bestmode); | |
1065 | xbitpos = bitnum % unit; | |
1066 | xop0 = change_address (xop0, bestmode, | |
1067 | plus_constant (XEXP (xop0, 0), | |
1068 | xoffset)); | |
1069 | /* Fetch it to a register in that size. */ | |
1070 | xop0 = force_reg (bestmode, xop0); | |
1071 | ||
1072 | /* XBITPOS counts within UNIT, which is what is expected. */ | |
1073 | } | |
1074 | else | |
1075 | /* Get ref to first byte containing part of the field. */ | |
1076 | xop0 = change_address (xop0, byte_mode, | |
1077 | plus_constant (XEXP (xop0, 0), xoffset)); | |
1078 | } | |
1079 | ||
1080 | /* If op0 is a register, we need it in MAXMODE (which is usually | |
1081 | SImode) to make it acceptable to the format of extv. */ | |
1082 | if (GET_CODE (xop0) == SUBREG && GET_MODE (xop0) != maxmode) | |
1083 | abort (); | |
1084 | if (GET_CODE (xop0) == REG && GET_MODE (xop0) != maxmode) | |
1085 | xop0 = gen_rtx (SUBREG, maxmode, xop0, 0); | |
1086 | ||
1087 | /* On big-endian machines, we count bits from the most significant. | |
1088 | If the bit field insn does not, we must invert. */ | |
1089 | #if BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN | |
1090 | xbitpos = unit - bitsize - xbitpos; | |
1091 | #endif | |
1092 | /* XBITPOS counts within a size of UNIT. | |
1093 | Adjust to count within a size of MAXMODE. */ | |
1094 | #if BITS_BIG_ENDIAN | |
1095 | if (GET_CODE (xop0) != MEM) | |
1096 | xbitpos += (GET_MODE_BITSIZE (maxmode) - unit); | |
1097 | #endif | |
1098 | unit = GET_MODE_BITSIZE (maxmode); | |
1099 | ||
1100 | if (xtarget == 0 | |
1101 | || (flag_force_mem && GET_CODE (xtarget) == MEM)) | |
1102 | xtarget = xspec_target = gen_reg_rtx (tmode); | |
1103 | ||
1104 | if (GET_MODE (xtarget) != maxmode) | |
1105 | { | |
1106 | if (GET_CODE (xtarget) == REG) | |
b7a09135 RS |
1107 | { |
1108 | int wider = (GET_MODE_SIZE (maxmode) | |
1109 | > GET_MODE_SIZE (GET_MODE (xtarget))); | |
1110 | xtarget = gen_lowpart (maxmode, xtarget); | |
1111 | if (wider) | |
1112 | xspec_target_subreg = xtarget; | |
1113 | } | |
44037a66 TG |
1114 | else |
1115 | xtarget = gen_reg_rtx (maxmode); | |
1116 | } | |
1117 | ||
1118 | /* If this machine's extv insists on a register target, | |
1119 | make sure we have one. */ | |
1120 | if (! ((*insn_operand_predicate[(int) CODE_FOR_extv][0]) | |
1121 | (xtarget, maxmode))) | |
1122 | xtarget = gen_reg_rtx (maxmode); | |
1123 | ||
1124 | bitsize_rtx = gen_rtx (CONST_INT, VOIDmode, bitsize); | |
1125 | bitpos_rtx = gen_rtx (CONST_INT, VOIDmode, xbitpos); | |
1126 | ||
1127 | pat = gen_extv (protect_from_queue (xtarget, 1), | |
1128 | xop0, bitsize_rtx, bitpos_rtx); | |
1129 | if (pat) | |
1130 | { | |
1131 | emit_insn (pat); | |
1132 | target = xtarget; | |
1133 | spec_target = xspec_target; | |
1134 | spec_target_subreg = xspec_target_subreg; | |
1135 | } | |
1136 | else | |
1137 | { | |
1138 | delete_insns_since (last); | |
1139 | target = extract_fixed_bit_field (tmode, op0, offset, bitsize, | |
1140 | bitpos, target, 0, align); | |
1141 | } | |
1142 | } | |
1143 | else | |
1144 | extv_loses: | |
1145 | #endif | |
1146 | target = extract_fixed_bit_field (tmode, op0, offset, bitsize, bitpos, | |
1147 | target, 0, align); | |
1148 | } | |
1149 | if (target == spec_target) | |
1150 | return target; | |
1151 | if (target == spec_target_subreg) | |
1152 | return spec_target; | |
1153 | if (GET_MODE (target) != tmode && GET_MODE (target) != mode) | |
1154 | { | |
1155 | /* If the target mode is floating-point, first convert to the | |
1156 | integer mode of that size and then access it as a floating-point | |
1157 | value via a SUBREG. */ | |
1158 | if (GET_MODE_CLASS (tmode) == MODE_FLOAT) | |
1159 | { | |
1160 | target = convert_to_mode (mode_for_size (GET_MODE_BITSIZE (tmode), | |
1161 | MODE_INT, 0), | |
1162 | target, unsignedp); | |
1163 | if (GET_CODE (target) != REG) | |
1164 | target = copy_to_reg (target); | |
1165 | return gen_rtx (SUBREG, tmode, target, 0); | |
1166 | } | |
1167 | else | |
1168 | return convert_to_mode (tmode, target, unsignedp); | |
1169 | } | |
1170 | return target; | |
1171 | } | |
1172 | \f | |
1173 | /* Extract a bit field using shifts and boolean operations | |
1174 | Returns an rtx to represent the value. | |
1175 | OP0 addresses a register (word) or memory (byte). | |
1176 | BITPOS says which bit within the word or byte the bit field starts in. | |
1177 | OFFSET says how many bytes farther the bit field starts; | |
1178 | it is 0 if OP0 is a register. | |
1179 | BITSIZE says how many bits long the bit field is. | |
1180 | (If OP0 is a register, it may be narrower than a full word, | |
1181 | but BITPOS still counts within a full word, | |
1182 | which is significant on bigendian machines.) | |
1183 | ||
1184 | UNSIGNEDP is nonzero for an unsigned bit field (don't sign-extend value). | |
1185 | If TARGET is nonzero, attempts to store the value there | |
1186 | and return TARGET, but this is not guaranteed. | |
1187 | If TARGET is not used, create a pseudo-reg of mode TMODE for the value. | |
1188 | ||
1189 | ALIGN is the alignment that STR_RTX is known to have, measured in bytes. */ | |
1190 | ||
1191 | static rtx | |
1192 | extract_fixed_bit_field (tmode, op0, offset, bitsize, bitpos, | |
1193 | target, unsignedp, align) | |
1194 | enum machine_mode tmode; | |
1195 | register rtx op0, target; | |
1196 | register int offset, bitsize, bitpos; | |
1197 | int unsignedp; | |
1198 | int align; | |
1199 | { | |
1200 | int total_bits = BITS_PER_WORD; | |
1201 | enum machine_mode mode; | |
1202 | ||
1203 | if (GET_CODE (op0) == SUBREG || GET_CODE (op0) == REG) | |
1204 | { | |
1205 | /* Special treatment for a bit field split across two registers. */ | |
1206 | if (bitsize + bitpos > BITS_PER_WORD) | |
1207 | return extract_split_bit_field (op0, bitsize, bitpos, | |
1208 | unsignedp, align); | |
1209 | } | |
1210 | else | |
1211 | { | |
1212 | /* Get the proper mode to use for this field. We want a mode that | |
1213 | includes the entire field. If such a mode would be larger than | |
1214 | a word, we won't be doing the extraction the normal way. */ | |
1215 | ||
1216 | mode = get_best_mode (bitsize, bitpos + offset * BITS_PER_UNIT, | |
1217 | align * BITS_PER_UNIT, word_mode, | |
1218 | GET_CODE (op0) == MEM && MEM_VOLATILE_P (op0)); | |
1219 | ||
1220 | if (mode == VOIDmode) | |
1221 | /* The only way this should occur is if the field spans word | |
1222 | boundaries. */ | |
1223 | return extract_split_bit_field (op0, bitsize, | |
1224 | bitpos + offset * BITS_PER_UNIT, | |
1225 | unsignedp, align); | |
1226 | ||
1227 | total_bits = GET_MODE_BITSIZE (mode); | |
1228 | ||
1229 | /* Get ref to an aligned byte, halfword, or word containing the field. | |
1230 | Adjust BITPOS to be position within a word, | |
1231 | and OFFSET to be the offset of that word. | |
1232 | Then alter OP0 to refer to that word. */ | |
1233 | bitpos += (offset % (total_bits / BITS_PER_UNIT)) * BITS_PER_UNIT; | |
1234 | offset -= (offset % (total_bits / BITS_PER_UNIT)); | |
1235 | op0 = change_address (op0, mode, | |
1236 | plus_constant (XEXP (op0, 0), offset)); | |
1237 | } | |
1238 | ||
1239 | mode = GET_MODE (op0); | |
1240 | ||
1241 | #if BYTES_BIG_ENDIAN | |
1242 | /* BITPOS is the distance between our msb and that of OP0. | |
1243 | Convert it to the distance from the lsb. */ | |
1244 | ||
1245 | bitpos = total_bits - bitsize - bitpos; | |
1246 | #endif | |
1247 | /* Now BITPOS is always the distance between the field's lsb and that of OP0. | |
1248 | We have reduced the big-endian case to the little-endian case. */ | |
1249 | ||
1250 | if (unsignedp) | |
1251 | { | |
1252 | if (bitpos) | |
1253 | { | |
1254 | /* If the field does not already start at the lsb, | |
1255 | shift it so it does. */ | |
1256 | tree amount = build_int_2 (bitpos, 0); | |
1257 | /* Maybe propagate the target for the shift. */ | |
1258 | /* But not if we will return it--could confuse integrate.c. */ | |
1259 | rtx subtarget = (target != 0 && GET_CODE (target) == REG | |
1260 | && !REG_FUNCTION_VALUE_P (target) | |
1261 | ? target : 0); | |
1262 | if (tmode != mode) subtarget = 0; | |
1263 | op0 = expand_shift (RSHIFT_EXPR, mode, op0, amount, subtarget, 1); | |
1264 | } | |
1265 | /* Convert the value to the desired mode. */ | |
1266 | if (mode != tmode) | |
1267 | op0 = convert_to_mode (tmode, op0, 1); | |
1268 | ||
1269 | /* Unless the msb of the field used to be the msb when we shifted, | |
1270 | mask out the upper bits. */ | |
1271 | ||
1272 | if (GET_MODE_BITSIZE (mode) != bitpos + bitsize | |
1273 | #if 0 | |
1274 | #ifdef SLOW_ZERO_EXTEND | |
1275 | /* Always generate an `and' if | |
1276 | we just zero-extended op0 and SLOW_ZERO_EXTEND, since it | |
1277 | will combine fruitfully with the zero-extend. */ | |
1278 | || tmode != mode | |
1279 | #endif | |
1280 | #endif | |
1281 | ) | |
1282 | return expand_binop (GET_MODE (op0), and_optab, op0, | |
1283 | mask_rtx (GET_MODE (op0), 0, bitsize, 0), | |
1284 | target, 1, OPTAB_LIB_WIDEN); | |
1285 | return op0; | |
1286 | } | |
1287 | ||
1288 | /* To extract a signed bit-field, first shift its msb to the msb of the word, | |
1289 | then arithmetic-shift its lsb to the lsb of the word. */ | |
1290 | op0 = force_reg (mode, op0); | |
1291 | if (mode != tmode) | |
1292 | target = 0; | |
1293 | ||
1294 | /* Find the narrowest integer mode that contains the field. */ | |
1295 | ||
1296 | for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT); mode != VOIDmode; | |
1297 | mode = GET_MODE_WIDER_MODE (mode)) | |
1298 | if (GET_MODE_BITSIZE (mode) >= bitsize + bitpos) | |
1299 | { | |
1300 | op0 = convert_to_mode (mode, op0, 0); | |
1301 | break; | |
1302 | } | |
1303 | ||
1304 | if (GET_MODE_BITSIZE (mode) != (bitsize + bitpos)) | |
1305 | { | |
1306 | tree amount = build_int_2 (GET_MODE_BITSIZE (mode) - (bitsize + bitpos), 0); | |
1307 | /* Maybe propagate the target for the shift. */ | |
1308 | /* But not if we will return the result--could confuse integrate.c. */ | |
1309 | rtx subtarget = (target != 0 && GET_CODE (target) == REG | |
1310 | && ! REG_FUNCTION_VALUE_P (target) | |
1311 | ? target : 0); | |
1312 | op0 = expand_shift (LSHIFT_EXPR, mode, op0, amount, subtarget, 1); | |
1313 | } | |
1314 | ||
1315 | return expand_shift (RSHIFT_EXPR, mode, op0, | |
1316 | build_int_2 (GET_MODE_BITSIZE (mode) - bitsize, 0), | |
1317 | target, 0); | |
1318 | } | |
1319 | \f | |
1320 | /* Return a constant integer (CONST_INT or CONST_DOUBLE) mask value | |
1321 | of mode MODE with BITSIZE ones followed by BITPOS zeros, or the | |
1322 | complement of that if COMPLEMENT. The mask is truncated if | |
1323 | necessary to the width of mode MODE. */ | |
1324 | ||
1325 | static rtx | |
1326 | mask_rtx (mode, bitpos, bitsize, complement) | |
1327 | enum machine_mode mode; | |
1328 | int bitpos, bitsize, complement; | |
1329 | { | |
1330 | int masklow, maskhigh; | |
1331 | ||
1332 | if (bitpos < HOST_BITS_PER_INT) | |
1333 | masklow = -1 << bitpos; | |
1334 | else | |
1335 | masklow = 0; | |
1336 | ||
1337 | if (bitpos + bitsize < HOST_BITS_PER_INT) | |
1338 | masklow &= (unsigned) -1 >> (HOST_BITS_PER_INT - bitpos - bitsize); | |
1339 | ||
1340 | if (bitpos <= HOST_BITS_PER_INT) | |
1341 | maskhigh = -1; | |
1342 | else | |
1343 | maskhigh = -1 << (bitpos - HOST_BITS_PER_INT); | |
1344 | ||
1345 | if (bitpos + bitsize > HOST_BITS_PER_INT) | |
1346 | maskhigh &= (unsigned) -1 >> (2 * HOST_BITS_PER_INT - bitpos - bitsize); | |
1347 | else | |
1348 | maskhigh = 0; | |
1349 | ||
1350 | if (complement) | |
1351 | { | |
1352 | maskhigh = ~maskhigh; | |
1353 | masklow = ~masklow; | |
1354 | } | |
1355 | ||
1356 | return immed_double_const (masklow, maskhigh, mode); | |
1357 | } | |
1358 | ||
1359 | /* Return a constant integer (CONST_INT or CONST_DOUBLE) rtx with the value | |
1360 | VALUE truncated to BITSIZE bits and then shifted left BITPOS bits. */ | |
1361 | ||
1362 | static rtx | |
1363 | lshift_value (mode, value, bitpos, bitsize) | |
1364 | enum machine_mode mode; | |
1365 | rtx value; | |
1366 | int bitpos, bitsize; | |
1367 | { | |
1368 | unsigned v = INTVAL (value); | |
1369 | int low, high; | |
1370 | ||
1371 | if (bitsize < HOST_BITS_PER_INT) | |
1372 | v &= ~(-1 << bitsize); | |
1373 | ||
1374 | if (bitpos < HOST_BITS_PER_INT) | |
1375 | { | |
1376 | low = v << bitpos; | |
1377 | high = (bitpos > 0 ? (v >> (HOST_BITS_PER_INT - bitpos)) : 0); | |
1378 | } | |
1379 | else | |
1380 | { | |
1381 | low = 0; | |
1382 | high = v << (bitpos - HOST_BITS_PER_INT); | |
1383 | } | |
1384 | ||
1385 | return immed_double_const (low, high, mode); | |
1386 | } | |
1387 | \f | |
1388 | /* Extract a bit field that is split across two words | |
1389 | and return an RTX for the result. | |
1390 | ||
1391 | OP0 is the REG, SUBREG or MEM rtx for the first of the two words. | |
1392 | BITSIZE is the field width; BITPOS, position of its first bit, in the word. | |
1393 | UNSIGNEDP is 1 if should zero-extend the contents; else sign-extend. */ | |
1394 | ||
1395 | static rtx | |
1396 | extract_split_bit_field (op0, bitsize, bitpos, unsignedp, align) | |
1397 | rtx op0; | |
1398 | int bitsize, bitpos, unsignedp, align; | |
1399 | { | |
1400 | /* BITSIZE_1 is size of the part in the first word. */ | |
1401 | int bitsize_1 = BITS_PER_WORD - bitpos % BITS_PER_WORD; | |
1402 | /* BITSIZE_2 is size of the rest (in the following word). */ | |
1403 | int bitsize_2 = bitsize - bitsize_1; | |
1404 | rtx part1, part2, result; | |
1405 | int unit = GET_CODE (op0) == MEM ? BITS_PER_UNIT : BITS_PER_WORD; | |
1406 | int offset = bitpos / unit; | |
1407 | rtx word; | |
1408 | ||
1409 | /* The field must span exactly one word boundary. */ | |
1410 | if (bitpos / BITS_PER_WORD != (bitpos + bitsize - 1) / BITS_PER_WORD - 1) | |
1411 | abort (); | |
1412 | ||
1413 | /* Get the part of the bit field from the first word. If OP0 is a MEM, | |
1414 | pass OP0 and the offset computed above. Otherwise, get the proper | |
1415 | word and pass an offset of zero. */ | |
1416 | word = (GET_CODE (op0) == MEM ? op0 | |
1417 | : operand_subword_force (op0, offset, GET_MODE (op0))); | |
1418 | part1 = extract_fixed_bit_field (word_mode, word, | |
1419 | GET_CODE (op0) == MEM ? offset : 0, | |
1420 | bitsize_1, bitpos % unit, 0, 1, align); | |
1421 | ||
1422 | /* Offset op0 by 1 word to get to the following one. */ | |
1423 | if (GET_CODE (op0) == SUBREG) | |
1424 | word = operand_subword_force (SUBREG_REG (op0), | |
1425 | SUBREG_WORD (op0) + offset + 1, VOIDmode); | |
1426 | else if (GET_CODE (op0) == MEM) | |
1427 | word = op0; | |
1428 | else | |
1429 | word = operand_subword_force (op0, offset + 1, GET_MODE (op0)); | |
1430 | ||
1431 | /* Get the part of the bit field from the second word. */ | |
1432 | part2 = extract_fixed_bit_field (word_mode, word, | |
1433 | (GET_CODE (op0) == MEM | |
1434 | ? CEIL (offset + 1, UNITS_PER_WORD) * UNITS_PER_WORD | |
1435 | : 0), | |
1436 | bitsize_2, 0, 0, 1, align); | |
1437 | ||
1438 | /* Shift the more significant part up to fit above the other part. */ | |
1439 | #if BYTES_BIG_ENDIAN | |
1440 | part1 = expand_shift (LSHIFT_EXPR, word_mode, part1, | |
1441 | build_int_2 (bitsize_2, 0), 0, 1); | |
1442 | #else | |
1443 | part2 = expand_shift (LSHIFT_EXPR, word_mode, part2, | |
1444 | build_int_2 (bitsize_1, 0), 0, 1); | |
1445 | #endif | |
1446 | ||
1447 | /* Combine the two parts with bitwise or. This works | |
1448 | because we extracted both parts as unsigned bit fields. */ | |
1449 | result = expand_binop (word_mode, ior_optab, part1, part2, 0, 1, | |
1450 | OPTAB_LIB_WIDEN); | |
1451 | ||
1452 | /* Unsigned bit field: we are done. */ | |
1453 | if (unsignedp) | |
1454 | return result; | |
1455 | /* Signed bit field: sign-extend with two arithmetic shifts. */ | |
1456 | result = expand_shift (LSHIFT_EXPR, word_mode, result, | |
1457 | build_int_2 (BITS_PER_WORD - bitsize, 0), 0, 0); | |
1458 | return expand_shift (RSHIFT_EXPR, word_mode, result, | |
1459 | build_int_2 (BITS_PER_WORD - bitsize, 0), 0, 0); | |
1460 | } | |
1461 | \f | |
1462 | /* Add INC into TARGET. */ | |
1463 | ||
1464 | void | |
1465 | expand_inc (target, inc) | |
1466 | rtx target, inc; | |
1467 | { | |
1468 | rtx value = expand_binop (GET_MODE (target), add_optab, | |
1469 | target, inc, | |
1470 | target, 0, OPTAB_LIB_WIDEN); | |
1471 | if (value != target) | |
1472 | emit_move_insn (target, value); | |
1473 | } | |
1474 | ||
1475 | /* Subtract DEC from TARGET. */ | |
1476 | ||
1477 | void | |
1478 | expand_dec (target, dec) | |
1479 | rtx target, dec; | |
1480 | { | |
1481 | rtx value = expand_binop (GET_MODE (target), sub_optab, | |
1482 | target, dec, | |
1483 | target, 0, OPTAB_LIB_WIDEN); | |
1484 | if (value != target) | |
1485 | emit_move_insn (target, value); | |
1486 | } | |
1487 | \f | |
1488 | /* Output a shift instruction for expression code CODE, | |
1489 | with SHIFTED being the rtx for the value to shift, | |
1490 | and AMOUNT the tree for the amount to shift by. | |
1491 | Store the result in the rtx TARGET, if that is convenient. | |
1492 | If UNSIGNEDP is nonzero, do a logical shift; otherwise, arithmetic. | |
1493 | Return the rtx for where the value is. */ | |
1494 | ||
1495 | rtx | |
1496 | expand_shift (code, mode, shifted, amount, target, unsignedp) | |
1497 | enum tree_code code; | |
1498 | register enum machine_mode mode; | |
1499 | rtx shifted; | |
1500 | tree amount; | |
1501 | register rtx target; | |
1502 | int unsignedp; | |
1503 | { | |
1504 | register rtx op1, temp = 0; | |
1505 | register int left = (code == LSHIFT_EXPR || code == LROTATE_EXPR); | |
1506 | register int rotate = (code == LROTATE_EXPR || code == RROTATE_EXPR); | |
1507 | int try; | |
1508 | ||
1509 | /* Previously detected shift-counts computed by NEGATE_EXPR | |
1510 | and shifted in the other direction; but that does not work | |
1511 | on all machines. */ | |
1512 | ||
1513 | op1 = expand_expr (amount, 0, VOIDmode, 0); | |
1514 | ||
1515 | if (op1 == const0_rtx) | |
1516 | return shifted; | |
1517 | ||
1518 | for (try = 0; temp == 0 && try < 3; try++) | |
1519 | { | |
1520 | enum optab_methods methods; | |
1521 | ||
1522 | if (try == 0) | |
1523 | methods = OPTAB_DIRECT; | |
1524 | else if (try == 1) | |
1525 | methods = OPTAB_WIDEN; | |
1526 | else | |
1527 | methods = OPTAB_LIB_WIDEN; | |
1528 | ||
1529 | if (rotate) | |
1530 | { | |
1531 | /* Widening does not work for rotation. */ | |
1532 | if (methods == OPTAB_WIDEN) | |
1533 | continue; | |
1534 | else if (methods == OPTAB_LIB_WIDEN) | |
1535 | methods = OPTAB_LIB; | |
1536 | ||
1537 | temp = expand_binop (mode, | |
1538 | left ? rotl_optab : rotr_optab, | |
1539 | shifted, op1, target, unsignedp, methods); | |
1540 | } | |
1541 | else if (unsignedp) | |
1542 | { | |
1543 | temp = expand_binop (mode, | |
1544 | left ? lshl_optab : lshr_optab, | |
1545 | shifted, op1, target, unsignedp, methods); | |
1546 | if (temp == 0 && left) | |
1547 | temp = expand_binop (mode, ashl_optab, | |
1548 | shifted, op1, target, unsignedp, methods); | |
1549 | } | |
1550 | ||
1551 | /* Do arithmetic shifts. | |
1552 | Also, if we are going to widen the operand, we can just as well | |
1553 | use an arithmetic right-shift instead of a logical one. */ | |
1554 | if (temp == 0 && ! rotate | |
1555 | && (! unsignedp || (! left && methods == OPTAB_WIDEN))) | |
1556 | { | |
1557 | enum optab_methods methods1 = methods; | |
1558 | ||
1559 | /* If trying to widen a log shift to an arithmetic shift, | |
1560 | don't accept an arithmetic shift of the same size. */ | |
1561 | if (unsignedp) | |
1562 | methods1 = OPTAB_MUST_WIDEN; | |
1563 | ||
1564 | /* Arithmetic shift */ | |
1565 | ||
1566 | temp = expand_binop (mode, | |
1567 | left ? ashl_optab : ashr_optab, | |
1568 | shifted, op1, target, unsignedp, methods1); | |
1569 | } | |
1570 | ||
1571 | #ifdef HAVE_extzv | |
1572 | /* We can do a logical (unsigned) right shift with a bit-field | |
1573 | extract insn. But first check if one of the above methods worked. */ | |
1574 | if (temp != 0) | |
1575 | return temp; | |
1576 | ||
1577 | if (unsignedp && code == RSHIFT_EXPR && ! BITS_BIG_ENDIAN && HAVE_extzv) | |
1578 | { | |
1579 | enum machine_mode output_mode | |
1580 | = insn_operand_mode[(int) CODE_FOR_extzv][0]; | |
1581 | ||
1582 | if ((methods == OPTAB_DIRECT && mode == output_mode) | |
1583 | || (methods == OPTAB_WIDEN | |
1584 | && GET_MODE_SIZE (mode) < GET_MODE_SIZE (output_mode))) | |
1585 | { | |
1586 | /* Note convert_to_mode does protect_from_queue. */ | |
1587 | rtx shifted1 = convert_to_mode (output_mode, shifted, 1); | |
1588 | enum machine_mode length_mode | |
1589 | = insn_operand_mode[(int) CODE_FOR_extzv][2]; | |
1590 | enum machine_mode pos_mode | |
1591 | = insn_operand_mode[(int) CODE_FOR_extzv][3]; | |
1592 | rtx target1 = 0; | |
1593 | rtx last = get_last_insn (); | |
1594 | rtx width; | |
1595 | rtx xop1 = op1; | |
1596 | rtx pat; | |
1597 | ||
1598 | if (target != 0) | |
1599 | target1 = protect_from_queue (target, 1); | |
1600 | ||
1601 | /* We define extract insns as having OUTPUT_MODE in a register | |
1602 | and the mode of operand 1 in memory. Since we want | |
1603 | OUTPUT_MODE, we will always force the operand into a | |
1604 | register. At some point we might want to support MEM | |
1605 | directly. */ | |
1606 | shifted1 = force_reg (output_mode, shifted1); | |
1607 | ||
1608 | /* If we don't have or cannot use a suggested target, | |
1609 | make a place for the result, in the proper mode. */ | |
1610 | if (methods == OPTAB_WIDEN || target1 == 0 | |
1611 | || ! ((*insn_operand_predicate[(int) CODE_FOR_extzv][0]) | |
1612 | (target1, output_mode))) | |
1613 | target1 = gen_reg_rtx (output_mode); | |
1614 | ||
1615 | xop1 = convert_to_mode (pos_mode, xop1, | |
1616 | TREE_UNSIGNED (TREE_TYPE (amount))); | |
1617 | ||
1618 | /* If this machine's extzv insists on a register for | |
1619 | operand 3 (position), arrange for that. */ | |
1620 | if (! ((*insn_operand_predicate[(int) CODE_FOR_extzv][3]) | |
1621 | (xop1, pos_mode))) | |
1622 | xop1 = force_reg (pos_mode, xop1); | |
1623 | ||
1624 | /* WIDTH gets the width of the bit field to extract: | |
1625 | wordsize minus # bits to shift by. */ | |
1626 | if (GET_CODE (xop1) == CONST_INT) | |
1627 | width = gen_rtx (CONST_INT, VOIDmode, | |
1628 | (GET_MODE_BITSIZE (mode) - INTVAL (op1))); | |
1629 | else | |
1630 | { | |
1631 | /* Now get the width in the proper mode. */ | |
1632 | width = convert_to_mode (length_mode, op1, | |
1633 | TREE_UNSIGNED (TREE_TYPE (amount))); | |
1634 | ||
1635 | width = expand_binop (length_mode, sub_optab, | |
1636 | gen_rtx (CONST_INT, VOIDmode, | |
1637 | GET_MODE_BITSIZE (mode)), | |
1638 | width, 0, 0, OPTAB_LIB_WIDEN); | |
1639 | } | |
1640 | ||
1641 | /* If this machine's extzv insists on a register for | |
1642 | operand 2 (length), arrange for that. */ | |
1643 | if (! ((*insn_operand_predicate[(int) CODE_FOR_extzv][2]) | |
1644 | (width, length_mode))) | |
1645 | width = force_reg (length_mode, width); | |
1646 | ||
1647 | /* Now extract with WIDTH, omitting OP1 least sig bits. */ | |
1648 | pat = gen_extzv (target1, shifted1, width, xop1); | |
1649 | if (pat) | |
1650 | { | |
1651 | emit_insn (pat); | |
1652 | temp = convert_to_mode (mode, target1, 1); | |
1653 | } | |
1654 | else | |
1655 | delete_insns_since (last); | |
1656 | } | |
1657 | ||
1658 | /* Can also do logical shift with signed bit-field extract | |
1659 | followed by inserting the bit-field at a different position. | |
1660 | That strategy is not yet implemented. */ | |
1661 | } | |
1662 | #endif /* HAVE_extzv */ | |
1663 | } | |
1664 | ||
1665 | if (temp == 0) | |
1666 | abort (); | |
1667 | return temp; | |
1668 | } | |
1669 | \f | |
1670 | enum alg_code { alg_add, alg_subtract, alg_compound }; | |
1671 | ||
1672 | /* This structure records a sequence of operations. | |
1673 | `ops' is the number of operations recorded. | |
1674 | `cost' is their total cost. | |
1675 | The operations are stored in `op' and the corresponding | |
1676 | integer coefficients in `coeff'. | |
1677 | These are the operations: | |
1678 | alg_add Add to the total the multiplicand times the coefficient. | |
1679 | alg_subtract Subtract the multiplicand times the coefficient. | |
1680 | alg_compound This coefficient plus or minus the following one | |
1681 | is multiplied into the total. The following operation | |
1682 | is alg_add or alg_subtract to indicate whether to add | |
1683 | or subtract the two coefficients. */ | |
1684 | ||
1685 | #ifndef MAX_BITS_PER_WORD | |
1686 | #define MAX_BITS_PER_WORD BITS_PER_WORD | |
1687 | #endif | |
1688 | ||
1689 | struct algorithm | |
1690 | { | |
1691 | int cost; | |
1692 | unsigned int ops; | |
1693 | enum alg_code op[MAX_BITS_PER_WORD]; | |
1694 | unsigned int coeff[MAX_BITS_PER_WORD]; | |
1695 | }; | |
1696 | ||
1697 | /* Compute and return the best algorithm for multiplying by T. | |
1698 | Assume that add insns cost ADD_COST and shifts cost SHIFT_COST. | |
1699 | Return cost -1 if would cost more than MAX_COST. */ | |
1700 | ||
1701 | static struct algorithm | |
1702 | synth_mult (t, add_cost, shift_cost, max_cost) | |
1703 | unsigned int t; | |
1704 | int add_cost, shift_cost; | |
1705 | int max_cost; | |
1706 | { | |
1707 | int m, n; | |
1708 | struct algorithm *best_alg = (struct algorithm *)alloca (sizeof (struct algorithm)); | |
1709 | struct algorithm *alg_in = (struct algorithm *)alloca (sizeof (struct algorithm)); | |
1710 | unsigned int cost; | |
1711 | ||
1712 | /* No matter what happens, we want to return a valid algorithm. */ | |
1713 | best_alg->cost = max_cost; | |
1714 | best_alg->ops = 0; | |
1715 | ||
1716 | /* Is t an exponent of 2, so we can just do a shift? */ | |
1717 | ||
1718 | if ((t & -t) == t) | |
1719 | { | |
1720 | if (t > 1) | |
1721 | { | |
1722 | if (max_cost >= shift_cost) | |
1723 | { | |
1724 | best_alg->cost = shift_cost; | |
1725 | best_alg->ops = 1; | |
1726 | best_alg->op[0] = alg_add; | |
1727 | best_alg->coeff[0] = t; | |
1728 | } | |
1729 | else | |
1730 | best_alg->cost = -1; | |
1731 | } | |
1732 | else if (t == 1) | |
1733 | { | |
1734 | if (max_cost >= 0) | |
1735 | best_alg->cost = 0; | |
1736 | } | |
1737 | else | |
1738 | best_alg->cost = 0; | |
1739 | ||
1740 | return *best_alg; | |
1741 | } | |
1742 | ||
1743 | /* If MAX_COST just permits as little as an addition (or less), we won't | |
1744 | succeed in synthesizing an algorithm for t. Return immediately with | |
1745 | an indication of failure. */ | |
1746 | if (max_cost <= add_cost) | |
1747 | { | |
1748 | best_alg->cost = -1; | |
1749 | return *best_alg; | |
1750 | } | |
1751 | ||
1752 | /* Look for factors of t of the form | |
1753 | t = q(2**m +- 1), 2 <= m <= floor(log2(t)) - 1. | |
1754 | If we find such a factor, we can multiply by t using an algorithm that | |
1755 | multiplies by q, shift the result by m and add/subtract it to itself. */ | |
1756 | ||
1757 | for (m = floor_log2 (t) - 1; m >= 2; m--) | |
1758 | { | |
1759 | int m_exp_2 = 1 << m; | |
1760 | int d; | |
1761 | ||
1762 | d = m_exp_2 + 1; | |
1763 | if (t % d == 0) | |
1764 | { | |
1765 | int q = t / d; | |
1766 | ||
1767 | cost = add_cost + shift_cost * 2; | |
1768 | ||
1769 | *alg_in = synth_mult (q, add_cost, shift_cost, | |
1770 | MIN (max_cost, best_alg->cost) - cost); | |
1771 | ||
1772 | if (alg_in->cost >= 0) | |
1773 | { | |
1774 | cost += alg_in->cost; | |
1775 | ||
1776 | if (cost < best_alg->cost) | |
1777 | { | |
1778 | struct algorithm *x; | |
1779 | x = alg_in; | |
1780 | alg_in = best_alg; | |
1781 | best_alg = x; | |
1782 | best_alg->coeff[best_alg->ops] = m_exp_2; | |
1783 | best_alg->op[best_alg->ops++] = alg_compound; | |
1784 | best_alg->coeff[best_alg->ops] = 1; | |
1785 | best_alg->op[best_alg->ops++] = alg_add; | |
1786 | best_alg->cost = cost; | |
1787 | } | |
1788 | } | |
1789 | } | |
1790 | ||
1791 | d = m_exp_2 - 1; | |
1792 | if (t % d == 0) | |
1793 | { | |
1794 | int q = t / d; | |
1795 | ||
1796 | cost = add_cost + shift_cost * 2; | |
1797 | ||
1798 | *alg_in = synth_mult (q, add_cost, shift_cost, | |
1799 | MIN (max_cost, best_alg->cost) - cost); | |
1800 | ||
1801 | if (alg_in->cost >= 0) | |
1802 | { | |
1803 | cost += alg_in->cost; | |
1804 | ||
1805 | if (cost < best_alg->cost) | |
1806 | { | |
1807 | struct algorithm *x; | |
1808 | x = alg_in; | |
1809 | alg_in = best_alg; | |
1810 | best_alg = x; | |
1811 | best_alg->coeff[best_alg->ops] = m_exp_2; | |
1812 | best_alg->op[best_alg->ops++] = alg_compound; | |
1813 | best_alg->coeff[best_alg->ops] = 1; | |
1814 | best_alg->op[best_alg->ops++] = alg_subtract; | |
1815 | best_alg->cost = cost; | |
1816 | } | |
1817 | } | |
1818 | } | |
1819 | } | |
1820 | ||
1821 | /* Try load effective address instructions, i.e. do a*3, a*5, a*9. */ | |
1822 | ||
1823 | { | |
1824 | int q; | |
1825 | int w; | |
1826 | ||
1827 | q = t & -t; /* get out lsb */ | |
1828 | w = (t - q) & -(t - q); /* get out next lsb */ | |
1829 | ||
1830 | if (w / q <= lea_max_mul) | |
1831 | { | |
1832 | cost = lea_cost + (q != 1 ? shift_cost : 0); | |
1833 | ||
1834 | *alg_in = synth_mult (t - q - w, add_cost, shift_cost, | |
1835 | MIN (max_cost, best_alg->cost) - cost); | |
1836 | ||
1837 | if (alg_in->cost >= 0) | |
1838 | { | |
1839 | cost += alg_in->cost; | |
1840 | ||
1841 | /* Use <= to prefer this method to the factoring method | |
1842 | when the cost appears the same, because this method | |
1843 | uses fewer temporary registers. */ | |
1844 | if (cost <= best_alg->cost) | |
1845 | { | |
1846 | struct algorithm *x; | |
1847 | x = alg_in; | |
1848 | alg_in = best_alg; | |
1849 | best_alg = x; | |
1850 | best_alg->coeff[best_alg->ops] = w; | |
1851 | best_alg->op[best_alg->ops++] = alg_add; | |
1852 | best_alg->coeff[best_alg->ops] = q; | |
1853 | best_alg->op[best_alg->ops++] = alg_add; | |
1854 | best_alg->cost = cost; | |
1855 | } | |
1856 | } | |
1857 | } | |
1858 | } | |
1859 | ||
1860 | /* Now, use the good old method to add or subtract at the leftmost | |
1861 | 1-bit. */ | |
1862 | ||
1863 | { | |
1864 | int q; | |
1865 | int w; | |
1866 | ||
1867 | q = t & -t; /* get out lsb */ | |
1868 | for (w = q; (w & t) != 0; w <<= 1) | |
1869 | ; | |
1870 | if ((w > q << 1) | |
1871 | /* Reject the case where t has only two bits. | |
1872 | Thus we prefer addition in that case. */ | |
1873 | && !(t < w && w == q << 2)) | |
1874 | { | |
1875 | /* There are many bits in a row. Make 'em by subtraction. */ | |
1876 | ||
1877 | cost = add_cost; | |
1878 | if (q != 1) | |
1879 | cost += shift_cost; | |
1880 | ||
1881 | *alg_in = synth_mult (t + q, add_cost, shift_cost, | |
1882 | MIN (max_cost, best_alg->cost) - cost); | |
1883 | ||
1884 | if (alg_in->cost >= 0) | |
1885 | { | |
1886 | cost += alg_in->cost; | |
1887 | ||
1888 | /* Use <= to prefer this method to the factoring method | |
1889 | when the cost appears the same, because this method | |
1890 | uses fewer temporary registers. */ | |
1891 | if (cost <= best_alg->cost) | |
1892 | { | |
1893 | struct algorithm *x; | |
1894 | x = alg_in; | |
1895 | alg_in = best_alg; | |
1896 | best_alg = x; | |
1897 | best_alg->coeff[best_alg->ops] = q; | |
1898 | best_alg->op[best_alg->ops++] = alg_subtract; | |
1899 | best_alg->cost = cost; | |
1900 | } | |
1901 | } | |
1902 | } | |
1903 | else | |
1904 | { | |
1905 | /* There's only one bit at the left. Make it by addition. */ | |
1906 | ||
1907 | cost = add_cost; | |
1908 | if (q != 1) | |
1909 | cost += shift_cost; | |
1910 | ||
1911 | *alg_in = synth_mult (t - q, add_cost, shift_cost, | |
1912 | MIN (max_cost, best_alg->cost) - cost); | |
1913 | ||
1914 | if (alg_in->cost >= 0) | |
1915 | { | |
1916 | cost += alg_in->cost; | |
1917 | ||
1918 | if (cost <= best_alg->cost) | |
1919 | { | |
1920 | struct algorithm *x; | |
1921 | x = alg_in; | |
1922 | alg_in = best_alg; | |
1923 | best_alg = x; | |
1924 | best_alg->coeff[best_alg->ops] = q; | |
1925 | best_alg->op[best_alg->ops++] = alg_add; | |
1926 | best_alg->cost = cost; | |
1927 | } | |
1928 | } | |
1929 | } | |
1930 | } | |
1931 | ||
1932 | if (best_alg->cost >= max_cost) | |
1933 | best_alg->cost = -1; | |
1934 | return *best_alg; | |
1935 | } | |
1936 | \f | |
1937 | /* Perform a multiplication and return an rtx for the result. | |
1938 | MODE is mode of value; OP0 and OP1 are what to multiply (rtx's); | |
1939 | TARGET is a suggestion for where to store the result (an rtx). | |
1940 | ||
1941 | We check specially for a constant integer as OP1. | |
1942 | If you want this check for OP0 as well, then before calling | |
1943 | you should swap the two operands if OP0 would be constant. */ | |
1944 | ||
1945 | rtx | |
1946 | expand_mult (mode, op0, op1, target, unsignedp) | |
1947 | enum machine_mode mode; | |
1948 | register rtx op0, op1, target; | |
1949 | int unsignedp; | |
1950 | { | |
1951 | rtx const_op1 = op1; | |
1952 | ||
1953 | /* If we are multiplying in DImode, it may still be a win | |
1954 | to try to work with shifts and adds. */ | |
1955 | if (GET_CODE (op1) == CONST_DOUBLE | |
1956 | && GET_MODE_CLASS (GET_MODE (op1)) == MODE_INT | |
1957 | && HOST_BITS_PER_INT <= BITS_PER_WORD) | |
1958 | { | |
1959 | if ((CONST_DOUBLE_HIGH (op1) == 0 && CONST_DOUBLE_LOW (op1) >= 0) | |
1960 | || (CONST_DOUBLE_HIGH (op1) == -1 && CONST_DOUBLE_LOW (op1) < 0)) | |
1961 | const_op1 = gen_rtx (CONST_INT, VOIDmode, CONST_DOUBLE_LOW (op1)); | |
1962 | } | |
1963 | ||
66c1f88e RS |
1964 | /* We used to test optimize here, on the grounds that it's better to |
1965 | produce a smaller program when -O is not used. | |
1966 | But this causes such a terrible slowdown sometimes | |
1967 | that it seems better to use synth_mult always. */ | |
1968 | if (GET_CODE (const_op1) == CONST_INT && ! mult_is_very_cheap) | |
44037a66 TG |
1969 | { |
1970 | struct algorithm alg; | |
1971 | struct algorithm neg_alg; | |
1972 | int negate = 0; | |
1973 | int absval = INTVAL (op1); | |
1974 | rtx last; | |
1975 | ||
1976 | /* Try to do the computation two ways: multiply by the negative of OP1 | |
1977 | and then negate, or do the multiplication directly. The latter is | |
1978 | usually faster for positive numbers and the former for negative | |
1979 | numbers, but the opposite can be faster if the original value | |
1980 | has a factor of 2**m +/- 1, while the negated value does not or | |
1981 | vice versa. */ | |
1982 | ||
1983 | alg = synth_mult (absval, add_cost, shift_cost, mult_cost); | |
1984 | neg_alg = synth_mult (- absval, add_cost, shift_cost, | |
1985 | mult_cost - negate_cost); | |
1986 | ||
1987 | if (neg_alg.cost >= 0 && neg_alg.cost + negate_cost < alg.cost) | |
1988 | alg = neg_alg, negate = 1, absval = - absval; | |
1989 | ||
1990 | if (alg.cost >= 0) | |
1991 | { | |
1992 | /* If we found something, it must be cheaper than multiply. | |
1993 | So use it. */ | |
1994 | int opno = 0; | |
1995 | rtx accum, tem; | |
1996 | int factors_seen = 0; | |
1997 | ||
1998 | op0 = protect_from_queue (op0, 0); | |
1999 | ||
2000 | /* Avoid referencing memory over and over. | |
2001 | For speed, but also for correctness when mem is volatile. */ | |
2002 | if (GET_CODE (op0) == MEM) | |
2003 | op0 = force_reg (mode, op0); | |
2004 | ||
2005 | if (alg.ops == 0) | |
2006 | accum = copy_to_mode_reg (mode, op0); | |
2007 | else | |
2008 | { | |
2009 | /* 1 if this is the last in a series of adds and subtracts. */ | |
2010 | int last = (1 == alg.ops || alg.op[1] == alg_compound); | |
2011 | int log = floor_log2 (alg.coeff[0]); | |
2012 | if (! factors_seen && ! last) | |
2013 | log -= floor_log2 (alg.coeff[1]); | |
2014 | ||
2015 | if (alg.op[0] != alg_add) | |
2016 | abort (); | |
2017 | accum = expand_shift (LSHIFT_EXPR, mode, op0, | |
2018 | build_int_2 (log, 0), | |
2019 | 0, 0); | |
2020 | } | |
2021 | ||
2022 | while (++opno < alg.ops) | |
2023 | { | |
2024 | int log = floor_log2 (alg.coeff[opno]); | |
2025 | /* 1 if this is the last in a series of adds and subtracts. */ | |
2026 | int last = (opno + 1 == alg.ops | |
2027 | || alg.op[opno + 1] == alg_compound); | |
2028 | ||
2029 | /* If we have not yet seen any separate factors (alg_compound) | |
2030 | then turn op0<<a1 + op0<<a2 + op0<<a3... into | |
2031 | (op0<<(a1-a2) + op0)<<(a2-a3) + op0... */ | |
2032 | switch (alg.op[opno]) | |
2033 | { | |
2034 | case alg_add: | |
2035 | if (factors_seen) | |
2036 | { | |
2037 | tem = expand_shift (LSHIFT_EXPR, mode, op0, | |
2038 | build_int_2 (log, 0), 0, 0); | |
2039 | accum = force_operand (gen_rtx (PLUS, mode, accum, tem), | |
2040 | accum); | |
2041 | } | |
2042 | else | |
2043 | { | |
2044 | if (! last) | |
2045 | log -= floor_log2 (alg.coeff[opno + 1]); | |
2046 | accum = force_operand (gen_rtx (PLUS, mode, accum, op0), | |
2047 | accum); | |
2048 | accum = expand_shift (LSHIFT_EXPR, mode, accum, | |
2049 | build_int_2 (log, 0), accum, 0); | |
2050 | } | |
2051 | break; | |
2052 | ||
2053 | case alg_subtract: | |
2054 | if (factors_seen) | |
2055 | { | |
2056 | tem = expand_shift (LSHIFT_EXPR, mode, op0, | |
2057 | build_int_2 (log, 0), 0, 0); | |
2058 | accum = force_operand (gen_rtx (MINUS, mode, accum, tem), | |
2059 | accum); | |
2060 | } | |
2061 | else | |
2062 | { | |
2063 | if (! last) | |
2064 | log -= floor_log2 (alg.coeff[opno + 1]); | |
2065 | accum = force_operand (gen_rtx (MINUS, mode, accum, op0), | |
2066 | accum); | |
2067 | accum = expand_shift (LSHIFT_EXPR, mode, accum, | |
2068 | build_int_2 (log, 0), accum, 0); | |
2069 | } | |
2070 | ||
2071 | break; | |
2072 | ||
2073 | case alg_compound: | |
2074 | factors_seen = 1; | |
2075 | tem = expand_shift (LSHIFT_EXPR, mode, accum, | |
2076 | build_int_2 (log, 0), 0, 0); | |
2077 | ||
2078 | log = floor_log2 (alg.coeff[opno + 1]); | |
2079 | accum = expand_shift (LSHIFT_EXPR, mode, accum, | |
2080 | build_int_2 (log, 0), 0, 0); | |
2081 | opno++; | |
2082 | if (alg.op[opno] == alg_add) | |
2083 | accum = force_operand (gen_rtx (PLUS, mode, tem, accum), | |
2084 | tem); | |
2085 | else | |
2086 | accum = force_operand (gen_rtx (MINUS, mode, tem, accum), | |
2087 | tem); | |
2088 | } | |
2089 | } | |
2090 | ||
2091 | /* Write a REG_EQUAL note on the last insn so that we can cse | |
2092 | multiplication sequences. We need not do this if we were | |
2093 | multiplying by a power of two, since only one insn would have | |
2094 | been generated. | |
2095 | ||
2096 | ??? We could also write REG_EQUAL notes on the last insn of | |
2097 | each sequence that uses a single temporary, but it is not | |
2098 | clear how to calculate the partial product so far. | |
2099 | ||
2100 | Torbjorn: Can you do this? */ | |
2101 | ||
2102 | if (exact_log2 (absval) < 0) | |
2103 | { | |
2104 | last = get_last_insn (); | |
2105 | REG_NOTES (last) | |
2106 | = gen_rtx (EXPR_LIST, REG_EQUAL, | |
2107 | gen_rtx (MULT, mode, op0, | |
2108 | negate ? gen_rtx (CONST_INT, | |
2109 | VOIDmode, absval) | |
2110 | : op1), | |
2111 | REG_NOTES (last)); | |
2112 | } | |
2113 | ||
2114 | return (negate ? expand_unop (mode, neg_optab, accum, target, 0) | |
2115 | : accum); | |
2116 | } | |
2117 | } | |
2118 | ||
2119 | /* This used to use umul_optab if unsigned, | |
2120 | but I think that for non-widening multiply there is no difference | |
2121 | between signed and unsigned. */ | |
2122 | op0 = expand_binop (mode, smul_optab, | |
2123 | op0, op1, target, unsignedp, OPTAB_LIB_WIDEN); | |
2124 | if (op0 == 0) | |
2125 | abort (); | |
2126 | return op0; | |
2127 | } | |
2128 | \f | |
2129 | /* Emit the code to divide OP0 by OP1, putting the result in TARGET | |
2130 | if that is convenient, and returning where the result is. | |
2131 | You may request either the quotient or the remainder as the result; | |
2132 | specify REM_FLAG nonzero to get the remainder. | |
2133 | ||
2134 | CODE is the expression code for which kind of division this is; | |
2135 | it controls how rounding is done. MODE is the machine mode to use. | |
2136 | UNSIGNEDP nonzero means do unsigned division. */ | |
2137 | ||
2138 | /* ??? For CEIL_MOD_EXPR, can compute incorrect remainder with ANDI | |
2139 | and then correct it by or'ing in missing high bits | |
2140 | if result of ANDI is nonzero. | |
2141 | For ROUND_MOD_EXPR, can use ANDI and then sign-extend the result. | |
2142 | This could optimize to a bfexts instruction. | |
2143 | But C doesn't use these operations, so their optimizations are | |
2144 | left for later. */ | |
2145 | ||
2146 | rtx | |
2147 | expand_divmod (rem_flag, code, mode, op0, op1, target, unsignedp) | |
2148 | int rem_flag; | |
2149 | enum tree_code code; | |
2150 | enum machine_mode mode; | |
2151 | register rtx op0, op1, target; | |
2152 | int unsignedp; | |
2153 | { | |
2154 | register rtx result = 0; | |
2155 | enum machine_mode compute_mode; | |
2156 | int log = -1; | |
2157 | int can_clobber_op0; | |
2158 | int mod_insn_no_good = 0; | |
2159 | rtx adjusted_op0 = op0; | |
2160 | optab optab1, optab2; | |
2161 | ||
2162 | /* Don't use the function value register as a target | |
2163 | since we have to read it as well as write it, | |
2164 | and function-inlining gets confused by this. */ | |
2165 | if (target && REG_P (target) && REG_FUNCTION_VALUE_P (target)) | |
2166 | target = 0; | |
2167 | ||
2168 | /* Don't clobber an operand while doing a multi-step calculation. */ | |
2169 | if (target) | |
2170 | if ((rem_flag && (reg_mentioned_p (target, op0) | |
2171 | || (GET_CODE (op0) == MEM && GET_CODE (target) == MEM))) | |
2172 | || reg_mentioned_p (target, op1) | |
2173 | || (GET_CODE (op1) == MEM && GET_CODE (target) == MEM)) | |
2174 | target = 0; | |
2175 | ||
2176 | can_clobber_op0 = (GET_CODE (op0) == REG && op0 == target); | |
2177 | ||
2178 | if (GET_CODE (op1) == CONST_INT) | |
2179 | log = exact_log2 (INTVAL (op1)); | |
2180 | ||
2181 | /* If log is >= 0, we are dividing by 2**log, and will do it by shifting, | |
2182 | which is really floor-division. Otherwise we will really do a divide, | |
2183 | and we assume that is trunc-division. | |
2184 | ||
2185 | We must correct the dividend by adding or subtracting something | |
2186 | based on the divisor, in order to do the kind of rounding specified | |
2187 | by CODE. The correction depends on what kind of rounding is actually | |
2188 | available, and that depends on whether we will shift or divide. | |
2189 | ||
2190 | In many of these cases it is possible to perform the operation by a | |
2191 | clever series of logical operations (shifts and/or exclusive-ors). | |
2192 | Although avoiding the jump has the advantage that it extends the basic | |
2193 | block and allows further optimization, the branch-free code is normally | |
2194 | at least one instruction longer in the (most common) case where the | |
2195 | dividend is non-negative. Performance measurements of the two | |
2196 | alternatives show that the branch-free code is slightly faster on the | |
2197 | IBM ROMP but slower on CISC processors (significantly slower on the | |
2198 | VAX). Accordingly, the jump code has been retained. | |
2199 | ||
2200 | On machines where the jump code is slower, the cost of a DIV or MOD | |
2201 | operation can be set small (less than twice that of an addition); in | |
2202 | that case, we pretend that we don't have a power of two and perform | |
2203 | a normal division or modulus operation. */ | |
2204 | ||
2205 | if ((code == TRUNC_MOD_EXPR || code == TRUNC_DIV_EXPR) | |
2206 | && ! unsignedp | |
2207 | && (rem_flag ? smod_pow2_cheap : sdiv_pow2_cheap)) | |
2208 | log = -1; | |
2209 | ||
2210 | /* Get the mode in which to perform this computation. Normally it will | |
2211 | be MODE, but sometimes we can't do the desired operation in MODE. | |
2212 | If so, pick a wider mode in which we can do the operation. Convert | |
2213 | to that mode at the start to avoid repeated conversions. | |
2214 | ||
2215 | First see what operations we need. These depend on the expression | |
2216 | we are evaluating. (We assume that divxx3 insns exist under the | |
2217 | same conditions that modxx3 insns and that these insns don't normally | |
2218 | fail. If these assumptions are not correct, we may generate less | |
2219 | efficient code in some cases.) | |
2220 | ||
2221 | Then see if we find a mode in which we can open-code that operation | |
2222 | (either a division, modulus, or shift). Finally, check for the smallest | |
2223 | mode for which we can do the operation with a library call. */ | |
2224 | ||
2225 | optab1 = (log >= 0 ? (unsignedp ? lshr_optab : ashr_optab) | |
2226 | : (unsignedp ? udiv_optab : sdiv_optab)); | |
2227 | optab2 = (log >= 0 ? optab1 : (unsignedp ? udivmod_optab : sdivmod_optab)); | |
2228 | ||
2229 | for (compute_mode = mode; compute_mode != VOIDmode; | |
2230 | compute_mode = GET_MODE_WIDER_MODE (compute_mode)) | |
2231 | if (optab1->handlers[(int) compute_mode].insn_code != CODE_FOR_nothing | |
2232 | || optab2->handlers[(int) compute_mode].insn_code != CODE_FOR_nothing) | |
2233 | break; | |
2234 | ||
2235 | if (compute_mode == VOIDmode) | |
2236 | for (compute_mode = mode; compute_mode != VOIDmode; | |
2237 | compute_mode = GET_MODE_WIDER_MODE (compute_mode)) | |
2238 | if (optab1->handlers[(int) compute_mode].libfunc | |
2239 | || optab2->handlers[(int) compute_mode].libfunc) | |
2240 | break; | |
2241 | ||
2242 | /* If we still couldn't find a mode, use MODE; we'll probably abort in | |
2243 | expand_binop. */ | |
2244 | if (compute_mode == VOIDmode) | |
2245 | compute_mode = mode; | |
2246 | ||
2247 | /* Now convert to the best mode to use. Show we made a copy of OP0 | |
2248 | and hence we can clobber it (we cannot use a SUBREG to widen | |
2249 | something. */ | |
2250 | if (compute_mode != mode) | |
2251 | { | |
2252 | adjusted_op0 = op0 = convert_to_mode (compute_mode, op0, unsignedp); | |
2253 | can_clobber_op0 = 1; | |
2254 | op1 = convert_to_mode (compute_mode, op1, unsignedp); | |
2255 | } | |
2256 | ||
c2a47e48 RK |
2257 | /* If we are computing the remainder and one of the operands is a volatile |
2258 | MEM, copy it into a register. */ | |
2259 | ||
2260 | if (rem_flag && GET_CODE (op0) == MEM && MEM_VOLATILE_P (op0)) | |
2261 | adjusted_op0 = op0 = force_reg (compute_mode, op0), can_clobber_op0 = 1; | |
2262 | if (rem_flag && GET_CODE (op1) == MEM && MEM_VOLATILE_P (op1)) | |
2263 | op1 = force_reg (compute_mode, op1); | |
2264 | ||
d8064a5d RS |
2265 | /* If we are computing the remainder, op0 will be needed later to calculate |
2266 | X - Y * (X / Y), therefore cannot be clobbered. */ | |
2267 | if (rem_flag) | |
2268 | can_clobber_op0 = 0; | |
2269 | ||
44037a66 TG |
2270 | if (target == 0 || GET_MODE (target) != compute_mode) |
2271 | target = gen_reg_rtx (compute_mode); | |
2272 | ||
2273 | switch (code) | |
2274 | { | |
2275 | case TRUNC_MOD_EXPR: | |
2276 | case TRUNC_DIV_EXPR: | |
2277 | if (log >= 0 && ! unsignedp) | |
2278 | { | |
2279 | rtx label = gen_label_rtx (); | |
2280 | if (! can_clobber_op0) | |
2281 | { | |
36d747f6 RS |
2282 | adjusted_op0 = copy_to_suggested_reg (adjusted_op0, target, |
2283 | compute_mode); | |
44037a66 TG |
2284 | /* Copy op0 to a reg, since emit_cmp_insn will call emit_queue |
2285 | which will screw up mem refs for autoincrements. */ | |
2286 | op0 = force_reg (compute_mode, op0); | |
2287 | } | |
2288 | emit_cmp_insn (adjusted_op0, const0_rtx, GE, 0, compute_mode, 0, 0); | |
2289 | emit_jump_insn (gen_bge (label)); | |
2290 | expand_inc (adjusted_op0, plus_constant (op1, -1)); | |
2291 | emit_label (label); | |
2292 | mod_insn_no_good = 1; | |
2293 | } | |
2294 | break; | |
2295 | ||
2296 | case FLOOR_DIV_EXPR: | |
2297 | case FLOOR_MOD_EXPR: | |
2298 | if (log < 0 && ! unsignedp) | |
2299 | { | |
2300 | rtx label = gen_label_rtx (); | |
2301 | if (! can_clobber_op0) | |
2302 | { | |
36d747f6 RS |
2303 | adjusted_op0 = copy_to_suggested_reg (adjusted_op0, target, |
2304 | compute_mode); | |
44037a66 TG |
2305 | /* Copy op0 to a reg, since emit_cmp_insn will call emit_queue |
2306 | which will screw up mem refs for autoincrements. */ | |
2307 | op0 = force_reg (compute_mode, op0); | |
2308 | } | |
2309 | emit_cmp_insn (adjusted_op0, const0_rtx, GE, 0, compute_mode, 0, 0); | |
2310 | emit_jump_insn (gen_bge (label)); | |
2311 | expand_dec (adjusted_op0, op1); | |
2312 | expand_inc (adjusted_op0, const1_rtx); | |
2313 | emit_label (label); | |
2314 | mod_insn_no_good = 1; | |
2315 | } | |
2316 | break; | |
2317 | ||
2318 | case CEIL_DIV_EXPR: | |
2319 | case CEIL_MOD_EXPR: | |
2320 | if (! can_clobber_op0) | |
2321 | { | |
36d747f6 RS |
2322 | adjusted_op0 = copy_to_suggested_reg (adjusted_op0, target, |
2323 | compute_mode); | |
44037a66 TG |
2324 | /* Copy op0 to a reg, since emit_cmp_insn will call emit_queue |
2325 | which will screw up mem refs for autoincrements. */ | |
2326 | op0 = force_reg (compute_mode, op0); | |
2327 | } | |
2328 | if (log < 0) | |
2329 | { | |
2330 | rtx label = 0; | |
2331 | if (! unsignedp) | |
2332 | { | |
2333 | label = gen_label_rtx (); | |
2334 | emit_cmp_insn (adjusted_op0, const0_rtx, LE, 0, compute_mode, 0, 0); | |
2335 | emit_jump_insn (gen_ble (label)); | |
2336 | } | |
2337 | expand_inc (adjusted_op0, op1); | |
2338 | expand_dec (adjusted_op0, const1_rtx); | |
2339 | if (! unsignedp) | |
2340 | emit_label (label); | |
2341 | } | |
2342 | else | |
2343 | { | |
2344 | adjusted_op0 = expand_binop (compute_mode, add_optab, | |
2345 | adjusted_op0, plus_constant (op1, -1), | |
2346 | 0, 0, OPTAB_LIB_WIDEN); | |
2347 | } | |
2348 | mod_insn_no_good = 1; | |
2349 | break; | |
2350 | ||
2351 | case ROUND_DIV_EXPR: | |
2352 | case ROUND_MOD_EXPR: | |
2353 | if (! can_clobber_op0) | |
2354 | { | |
36d747f6 RS |
2355 | adjusted_op0 = copy_to_suggested_reg (adjusted_op0, target, |
2356 | compute_mode); | |
44037a66 TG |
2357 | /* Copy op0 to a reg, since emit_cmp_insn will call emit_queue |
2358 | which will screw up mem refs for autoincrements. */ | |
2359 | op0 = force_reg (compute_mode, op0); | |
2360 | } | |
2361 | if (log < 0) | |
2362 | { | |
2363 | op1 = expand_shift (RSHIFT_EXPR, compute_mode, op1, | |
2364 | integer_one_node, 0, 0); | |
2365 | if (! unsignedp) | |
2366 | { | |
2367 | rtx label = gen_label_rtx (); | |
2368 | emit_cmp_insn (adjusted_op0, const0_rtx, GE, 0, compute_mode, 0, 0); | |
2369 | emit_jump_insn (gen_bge (label)); | |
2370 | expand_unop (compute_mode, neg_optab, op1, op1, 0); | |
2371 | emit_label (label); | |
2372 | } | |
2373 | expand_inc (adjusted_op0, op1); | |
2374 | } | |
2375 | else | |
2376 | { | |
2377 | op1 = gen_rtx (CONST_INT, VOIDmode, (1 << log) / 2); | |
2378 | expand_inc (adjusted_op0, op1); | |
2379 | } | |
2380 | mod_insn_no_good = 1; | |
2381 | break; | |
2382 | } | |
2383 | ||
2384 | if (rem_flag && !mod_insn_no_good) | |
2385 | { | |
2386 | /* Try to produce the remainder directly */ | |
2387 | if (log >= 0) | |
2388 | result = expand_binop (compute_mode, and_optab, adjusted_op0, | |
2389 | gen_rtx (CONST_INT, VOIDmode, | |
2390 | (1 << log) - 1), | |
2391 | target, 1, OPTAB_LIB_WIDEN); | |
2392 | else | |
2393 | { | |
2394 | /* See if we can do remainder without a library call. */ | |
2395 | result = sign_expand_binop (mode, umod_optab, smod_optab, | |
2396 | adjusted_op0, op1, target, | |
2397 | unsignedp, OPTAB_WIDEN); | |
2398 | if (result == 0) | |
2399 | { | |
2400 | /* No luck there. Can we do remainder and divide at once | |
2401 | without a library call? */ | |
2402 | result = gen_reg_rtx (compute_mode); | |
2403 | if (! expand_twoval_binop (unsignedp | |
2404 | ? udivmod_optab : sdivmod_optab, | |
2405 | adjusted_op0, op1, | |
2406 | 0, result, unsignedp)) | |
2407 | result = 0; | |
2408 | } | |
2409 | } | |
2410 | } | |
2411 | ||
2412 | if (result) | |
2413 | return gen_lowpart (mode, result); | |
2414 | ||
2415 | /* Produce the quotient. */ | |
2416 | if (log >= 0) | |
2417 | result = expand_shift (RSHIFT_EXPR, compute_mode, adjusted_op0, | |
2418 | build_int_2 (log, 0), target, unsignedp); | |
2419 | else if (rem_flag && !mod_insn_no_good) | |
2420 | /* If producing quotient in order to subtract for remainder, | |
2421 | and a remainder subroutine would be ok, | |
2422 | don't use a divide subroutine. */ | |
2423 | result = sign_expand_binop (compute_mode, udiv_optab, sdiv_optab, | |
2424 | adjusted_op0, op1, 0, unsignedp, OPTAB_WIDEN); | |
2425 | else | |
2426 | { | |
2427 | /* Try a quotient insn, but not a library call. */ | |
2428 | result = sign_expand_binop (compute_mode, udiv_optab, sdiv_optab, | |
2429 | adjusted_op0, op1, rem_flag ? 0 : target, | |
2430 | unsignedp, OPTAB_WIDEN); | |
2431 | if (result == 0) | |
2432 | { | |
2433 | /* No luck there. Try a quotient-and-remainder insn, | |
2434 | keeping the quotient alone. */ | |
2435 | result = gen_reg_rtx (mode); | |
2436 | if (! expand_twoval_binop (unsignedp ? udivmod_optab : sdivmod_optab, | |
2437 | adjusted_op0, op1, | |
2438 | result, 0, unsignedp)) | |
2439 | result = 0; | |
2440 | } | |
2441 | ||
2442 | /* If still no luck, use a library call. */ | |
2443 | if (result == 0) | |
2444 | result = sign_expand_binop (compute_mode, udiv_optab, sdiv_optab, | |
2445 | adjusted_op0, op1, rem_flag ? 0 : target, | |
2446 | unsignedp, OPTAB_LIB_WIDEN); | |
2447 | } | |
2448 | ||
2449 | /* If we really want the remainder, get it by subtraction. */ | |
2450 | if (rem_flag) | |
2451 | { | |
2452 | if (result == 0) | |
2453 | /* No divide instruction either. Use library for remainder. */ | |
2454 | result = sign_expand_binop (compute_mode, umod_optab, smod_optab, | |
2455 | op0, op1, target, | |
2456 | unsignedp, OPTAB_LIB_WIDEN); | |
2457 | else | |
2458 | { | |
2459 | /* We divided. Now finish doing X - Y * (X / Y). */ | |
2460 | result = expand_mult (compute_mode, result, op1, target, unsignedp); | |
2461 | if (! result) abort (); | |
2462 | result = expand_binop (compute_mode, sub_optab, op0, | |
2463 | result, target, unsignedp, OPTAB_LIB_WIDEN); | |
2464 | } | |
2465 | } | |
2466 | ||
2467 | if (result == 0) | |
2468 | abort (); | |
2469 | ||
2470 | return gen_lowpart (mode, result); | |
2471 | } | |
2472 | \f | |
2473 | /* Return a tree node with data type TYPE, describing the value of X. | |
2474 | Usually this is an RTL_EXPR, if there is no obvious better choice. | |
2475 | X may be an expression, however we only support those expressions | |
2476 | generated by loop.c. */ | |
2477 | ||
2478 | tree | |
2479 | make_tree (type, x) | |
2480 | tree type; | |
2481 | rtx x; | |
2482 | { | |
2483 | tree t; | |
2484 | ||
2485 | switch (GET_CODE (x)) | |
2486 | { | |
2487 | case CONST_INT: | |
2488 | t = build_int_2 (INTVAL (x), | |
2489 | ! TREE_UNSIGNED (type) && INTVAL (x) >= 0 ? 0 : -1); | |
2490 | TREE_TYPE (t) = type; | |
2491 | return t; | |
2492 | ||
2493 | case CONST_DOUBLE: | |
2494 | if (GET_MODE (x) == VOIDmode) | |
2495 | { | |
2496 | t = build_int_2 (CONST_DOUBLE_LOW (x), CONST_DOUBLE_HIGH (x)); | |
2497 | TREE_TYPE (t) = type; | |
2498 | } | |
2499 | else | |
2500 | { | |
2501 | REAL_VALUE_TYPE d; | |
2502 | ||
2503 | REAL_VALUE_FROM_CONST_DOUBLE (d, x); | |
2504 | t = build_real (type, d); | |
2505 | } | |
2506 | ||
2507 | return t; | |
2508 | ||
2509 | case PLUS: | |
2510 | return fold (build (PLUS_EXPR, type, make_tree (type, XEXP (x, 0)), | |
2511 | make_tree (type, XEXP (x, 1)))); | |
2512 | ||
2513 | case MINUS: | |
2514 | return fold (build (MINUS_EXPR, type, make_tree (type, XEXP (x, 0)), | |
2515 | make_tree (type, XEXP (x, 1)))); | |
2516 | ||
2517 | case NEG: | |
2518 | return fold (build1 (NEGATE_EXPR, type, make_tree (type, XEXP (x, 0)))); | |
2519 | ||
2520 | case MULT: | |
2521 | return fold (build (MULT_EXPR, type, make_tree (type, XEXP (x, 0)), | |
2522 | make_tree (type, XEXP (x, 1)))); | |
2523 | ||
2524 | case ASHIFT: | |
2525 | return fold (build (LSHIFT_EXPR, type, make_tree (type, XEXP (x, 0)), | |
2526 | make_tree (type, XEXP (x, 1)))); | |
2527 | ||
2528 | case LSHIFTRT: | |
2529 | return fold (convert (type, | |
2530 | build (RSHIFT_EXPR, unsigned_type (type), | |
2531 | make_tree (unsigned_type (type), | |
2532 | XEXP (x, 0)), | |
2533 | make_tree (type, XEXP (x, 1))))); | |
2534 | ||
2535 | case ASHIFTRT: | |
2536 | return fold (convert (type, | |
2537 | build (RSHIFT_EXPR, signed_type (type), | |
2538 | make_tree (signed_type (type), XEXP (x, 0)), | |
2539 | make_tree (type, XEXP (x, 1))))); | |
2540 | ||
2541 | case DIV: | |
2542 | if (TREE_CODE (type) != REAL_TYPE) | |
2543 | t = signed_type (type); | |
2544 | else | |
2545 | t = type; | |
2546 | ||
2547 | return fold (convert (type, | |
2548 | build (TRUNC_DIV_EXPR, t, | |
2549 | make_tree (t, XEXP (x, 0)), | |
2550 | make_tree (t, XEXP (x, 1))))); | |
2551 | case UDIV: | |
2552 | t = unsigned_type (type); | |
2553 | return fold (convert (type, | |
2554 | build (TRUNC_DIV_EXPR, t, | |
2555 | make_tree (t, XEXP (x, 0)), | |
2556 | make_tree (t, XEXP (x, 1))))); | |
2557 | default: | |
2558 | t = make_node (RTL_EXPR); | |
2559 | TREE_TYPE (t) = type; | |
2560 | RTL_EXPR_RTL (t) = x; | |
2561 | /* There are no insns to be output | |
2562 | when this rtl_expr is used. */ | |
2563 | RTL_EXPR_SEQUENCE (t) = 0; | |
2564 | return t; | |
2565 | } | |
2566 | } | |
2567 | ||
2568 | /* Return an rtx representing the value of X * MULT + ADD. | |
2569 | TARGET is a suggestion for where to store the result (an rtx). | |
2570 | MODE is the machine mode for the computation. | |
2571 | X and MULT must have mode MODE. ADD may have a different mode. | |
2572 | So can X (defaults to same as MODE). | |
2573 | UNSIGNEDP is non-zero to do unsigned multiplication. | |
2574 | This may emit insns. */ | |
2575 | ||
2576 | rtx | |
2577 | expand_mult_add (x, target, mult, add, mode, unsignedp) | |
2578 | rtx x, target, mult, add; | |
2579 | enum machine_mode mode; | |
2580 | int unsignedp; | |
2581 | { | |
2582 | tree type = type_for_mode (mode, unsignedp); | |
2583 | tree add_type = (GET_MODE (add) == VOIDmode | |
36d747f6 | 2584 | ? type : type_for_mode (GET_MODE (add), unsignedp)); |
44037a66 TG |
2585 | tree result = fold (build (PLUS_EXPR, type, |
2586 | fold (build (MULT_EXPR, type, | |
2587 | make_tree (type, x), | |
2588 | make_tree (type, mult))), | |
2589 | make_tree (add_type, add))); | |
2590 | ||
2591 | return expand_expr (result, target, VOIDmode, 0); | |
2592 | } | |
2593 | \f | |
2594 | /* Compute the logical-and of OP0 and OP1, storing it in TARGET | |
2595 | and returning TARGET. | |
2596 | ||
2597 | If TARGET is 0, a pseudo-register or constant is returned. */ | |
2598 | ||
2599 | rtx | |
2600 | expand_and (op0, op1, target) | |
2601 | rtx op0, op1, target; | |
2602 | { | |
2603 | enum machine_mode mode = VOIDmode; | |
2604 | rtx tem; | |
2605 | ||
2606 | if (GET_MODE (op0) != VOIDmode) | |
2607 | mode = GET_MODE (op0); | |
2608 | else if (GET_MODE (op1) != VOIDmode) | |
2609 | mode = GET_MODE (op1); | |
2610 | ||
2611 | if (mode != VOIDmode) | |
2612 | tem = expand_binop (mode, and_optab, op0, op1, target, 0, OPTAB_LIB_WIDEN); | |
2613 | else if (GET_CODE (op0) == CONST_INT && GET_CODE (op1) == CONST_INT) | |
2614 | tem = gen_rtx (CONST_INT, VOIDmode, INTVAL (op0) & INTVAL (op1)); | |
2615 | else | |
2616 | abort (); | |
2617 | ||
2618 | if (target == 0) | |
2619 | target = tem; | |
2620 | else if (tem != target) | |
2621 | emit_move_insn (target, tem); | |
2622 | return target; | |
2623 | } | |
2624 | \f | |
2625 | /* Emit a store-flags instruction for comparison CODE on OP0 and OP1 | |
2626 | and storing in TARGET. Normally return TARGET. | |
2627 | Return 0 if that cannot be done. | |
2628 | ||
2629 | MODE is the mode to use for OP0 and OP1 should they be CONST_INTs. If | |
2630 | it is VOIDmode, they cannot both be CONST_INT. | |
2631 | ||
2632 | UNSIGNEDP is for the case where we have to widen the operands | |
2633 | to perform the operation. It says to use zero-extension. | |
2634 | ||
2635 | NORMALIZEP is 1 if we should convert the result to be either zero | |
2636 | or one one. Normalize is -1 if we should convert the result to be | |
2637 | either zero or -1. If NORMALIZEP is zero, the result will be left | |
2638 | "raw" out of the scc insn. */ | |
2639 | ||
2640 | rtx | |
2641 | emit_store_flag (target, code, op0, op1, mode, unsignedp, normalizep) | |
2642 | rtx target; | |
2643 | enum rtx_code code; | |
2644 | rtx op0, op1; | |
2645 | enum machine_mode mode; | |
2646 | int unsignedp; | |
2647 | int normalizep; | |
2648 | { | |
2649 | rtx subtarget; | |
2650 | enum insn_code icode; | |
2651 | enum machine_mode compare_mode; | |
2652 | enum machine_mode target_mode = GET_MODE (target); | |
2653 | rtx tem; | |
2654 | rtx last = 0; | |
2655 | rtx pattern, comparison; | |
2656 | ||
2657 | if (mode == VOIDmode) | |
2658 | mode = GET_MODE (op0); | |
2659 | ||
2660 | /* For some comparisons with 1 and -1, we can convert this to | |
2661 | comparisons with zero. This will often produce more opportunities for | |
2662 | store-flag insns. */ | |
2663 | ||
2664 | switch (code) | |
2665 | { | |
2666 | case LT: | |
2667 | if (op1 == const1_rtx) | |
2668 | op1 = const0_rtx, code = LE; | |
2669 | break; | |
2670 | case LE: | |
2671 | if (op1 == constm1_rtx) | |
2672 | op1 = const0_rtx, code = LT; | |
2673 | break; | |
2674 | case GE: | |
2675 | if (op1 == const1_rtx) | |
2676 | op1 = const0_rtx, code = GT; | |
2677 | break; | |
2678 | case GT: | |
2679 | if (op1 == constm1_rtx) | |
2680 | op1 = const0_rtx, code = GE; | |
2681 | break; | |
2682 | case GEU: | |
2683 | if (op1 == const1_rtx) | |
2684 | op1 = const0_rtx, code = NE; | |
2685 | break; | |
2686 | case LTU: | |
2687 | if (op1 == const1_rtx) | |
2688 | op1 = const0_rtx, code = EQ; | |
2689 | break; | |
2690 | } | |
2691 | ||
2692 | /* From now on, we won't change CODE, so set ICODE now. */ | |
2693 | icode = setcc_gen_code[(int) code]; | |
2694 | ||
2695 | /* If this is A < 0 or A >= 0, we can do this by taking the ones | |
2696 | complement of A (for GE) and shifting the sign bit to the low bit. */ | |
2697 | if (op1 == const0_rtx && (code == LT || code == GE) | |
2698 | && GET_MODE_CLASS (mode) == MODE_INT | |
2699 | && (normalizep || STORE_FLAG_VALUE == 1 | |
2700 | || (GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_INT | |
2701 | && STORE_FLAG_VALUE == 1 << (GET_MODE_BITSIZE (mode) - 1)))) | |
2702 | { | |
2703 | rtx subtarget = target; | |
2704 | ||
2705 | /* If the result is to be wider than OP0, it is best to convert it | |
2706 | first. If it is to be narrower, it is *incorrect* to convert it | |
2707 | first. */ | |
2708 | if (GET_MODE_SIZE (target_mode) > GET_MODE_SIZE (mode)) | |
2709 | { | |
2710 | op0 = convert_to_mode (target_mode, op0, 0); | |
2711 | mode = target_mode; | |
2712 | } | |
2713 | ||
2714 | if (target_mode != mode) | |
2715 | subtarget = 0; | |
2716 | ||
2717 | if (code == GE) | |
2718 | op0 = expand_unop (mode, one_cmpl_optab, op0, subtarget, 0); | |
2719 | ||
2720 | if (normalizep || STORE_FLAG_VALUE == 1) | |
2721 | /* If we are supposed to produce a 0/1 value, we want to do | |
2722 | a logical shift from the sign bit to the low-order bit; for | |
2723 | a -1/0 value, we do an arithmetic shift. */ | |
2724 | op0 = expand_shift (RSHIFT_EXPR, mode, op0, | |
2725 | size_int (GET_MODE_BITSIZE (mode) - 1), | |
2726 | subtarget, normalizep != -1); | |
2727 | ||
2728 | if (mode != target_mode) | |
2729 | op0 = convert_to_mode (target_mode, op0, 0); | |
2730 | ||
2731 | return op0; | |
2732 | } | |
2733 | ||
2734 | if (icode != CODE_FOR_nothing) | |
2735 | { | |
2736 | /* We think we may be able to do this with a scc insn. Emit the | |
2737 | comparison and then the scc insn. | |
2738 | ||
2739 | compare_from_rtx may call emit_queue, which would be deleted below | |
2740 | if the scc insn fails. So call it ourselves before setting LAST. */ | |
2741 | ||
2742 | emit_queue (); | |
2743 | last = get_last_insn (); | |
2744 | ||
2745 | comparison = compare_from_rtx (op0, op1, code, unsignedp, mode, 0, 0); | |
2746 | if (GET_CODE (comparison) == CONST_INT) | |
2747 | return (comparison == const0_rtx ? const0_rtx | |
2748 | : normalizep == 1 ? const1_rtx | |
2749 | : normalizep == -1 ? constm1_rtx | |
2750 | : const_true_rtx); | |
2751 | ||
2752 | /* Get a reference to the target in the proper mode for this insn. */ | |
2753 | compare_mode = insn_operand_mode[(int) icode][0]; | |
2754 | subtarget = target; | |
2755 | if (preserve_subexpressions_p () | |
2756 | || ! (*insn_operand_predicate[(int) icode][0]) (subtarget, compare_mode)) | |
2757 | subtarget = gen_reg_rtx (compare_mode); | |
2758 | ||
2759 | pattern = GEN_FCN (icode) (subtarget); | |
2760 | if (pattern) | |
2761 | { | |
2762 | emit_insn (pattern); | |
2763 | ||
2764 | /* If we are converting to a wider mode, first convert to | |
2765 | TARGET_MODE, then normalize. This produces better combining | |
2766 | opportunities on machines that have a SIGN_EXTRACT when we are | |
2767 | testing a single bit. This mostly benefits the 68k. | |
2768 | ||
2769 | If STORE_FLAG_VALUE does not have the sign bit set when | |
2770 | interpreted in COMPARE_MODE, we can do this conversion as | |
2771 | unsigned, which is usually more efficient. */ | |
2772 | if (GET_MODE_SIZE (target_mode) > GET_MODE_SIZE (compare_mode)) | |
2773 | { | |
2774 | convert_move (target, subtarget, | |
2775 | (GET_MODE_BITSIZE (compare_mode) | |
2776 | <= HOST_BITS_PER_INT) | |
2777 | && 0 == (STORE_FLAG_VALUE | |
2778 | & (1 << (GET_MODE_BITSIZE (compare_mode) -1)))); | |
2779 | op0 = target; | |
2780 | compare_mode = target_mode; | |
2781 | } | |
2782 | else | |
2783 | op0 = subtarget; | |
2784 | ||
4b980e20 RK |
2785 | /* If we want to keep subexpressions around, don't reuse our |
2786 | last target. */ | |
2787 | ||
2788 | if (preserve_subexpressions_p ()) | |
2789 | subtarget = 0; | |
2790 | ||
44037a66 TG |
2791 | /* Now normalize to the proper value in COMPARE_MODE. Sometimes |
2792 | we don't have to do anything. */ | |
2793 | if (normalizep == 0 || normalizep == STORE_FLAG_VALUE) | |
2794 | ; | |
2795 | else if (normalizep == - STORE_FLAG_VALUE) | |
2796 | op0 = expand_unop (compare_mode, neg_optab, op0, subtarget, 0); | |
2797 | ||
2798 | /* We don't want to use STORE_FLAG_VALUE < 0 below since this | |
2799 | makes it hard to use a value of just the sign bit due to | |
2800 | ANSI integer constant typing rules. */ | |
2801 | else if (GET_MODE_BITSIZE (compare_mode) <= HOST_BITS_PER_INT | |
2802 | && (STORE_FLAG_VALUE | |
2803 | & (1 << (GET_MODE_BITSIZE (compare_mode) - 1)))) | |
2804 | op0 = expand_shift (RSHIFT_EXPR, compare_mode, op0, | |
2805 | size_int (GET_MODE_BITSIZE (compare_mode) - 1), | |
2806 | subtarget, normalizep == 1); | |
2807 | else if (STORE_FLAG_VALUE & 1) | |
2808 | { | |
2809 | op0 = expand_and (op0, const1_rtx, subtarget); | |
2810 | if (normalizep == -1) | |
2811 | op0 = expand_unop (compare_mode, neg_optab, op0, op0, 0); | |
2812 | } | |
2813 | else | |
2814 | abort (); | |
2815 | ||
2816 | /* If we were converting to a smaller mode, do the | |
2817 | conversion now. */ | |
2818 | if (target_mode != compare_mode) | |
2819 | { | |
2820 | convert_move (target, op0); | |
2821 | return target; | |
2822 | } | |
2823 | else | |
2824 | return op0; | |
2825 | } | |
2826 | } | |
2827 | ||
2828 | if (last) | |
2829 | delete_insns_since (last); | |
2830 | ||
2831 | subtarget = target_mode == mode ? target : 0; | |
2832 | ||
2833 | /* If we reached here, we can't do this with a scc insn. However, there | |
2834 | are some comparisons that can be done directly. For example, if | |
2835 | this is an equality comparison of integers, we can try to exclusive-or | |
2836 | (or subtract) the two operands and use a recursive call to try the | |
2837 | comparison with zero. Don't do any of these cases if branches are | |
2838 | very cheap. */ | |
2839 | ||
2840 | if (BRANCH_COST >= 0 | |
2841 | && GET_MODE_CLASS (mode) == MODE_INT && (code == EQ || code == NE) | |
2842 | && op1 != const0_rtx) | |
2843 | { | |
2844 | tem = expand_binop (mode, xor_optab, op0, op1, subtarget, 1, | |
2845 | OPTAB_WIDEN); | |
2846 | ||
2847 | if (tem == 0) | |
2848 | tem = expand_binop (mode, sub_optab, op0, op1, subtarget, 1, | |
2849 | OPTAB_WIDEN); | |
2850 | if (tem != 0) | |
2851 | tem = emit_store_flag (target, code, tem, const0_rtx, | |
2852 | mode, unsignedp, normalizep); | |
2853 | if (tem == 0) | |
2854 | delete_insns_since (last); | |
2855 | return tem; | |
2856 | } | |
2857 | ||
2858 | /* Some other cases we can do are EQ, NE, LE, and GT comparisons with | |
2859 | the constant zero. Reject all other comparisons at this point. Only | |
2860 | do LE and GT if branches are expensive since they are expensive on | |
2861 | 2-operand machines. */ | |
2862 | ||
2863 | if (BRANCH_COST == 0 | |
2864 | || GET_MODE_CLASS (mode) != MODE_INT || op1 != const0_rtx | |
2865 | || (code != EQ && code != NE | |
2866 | && (BRANCH_COST <= 1 || (code != LE && code != GT)))) | |
2867 | return 0; | |
2868 | ||
2869 | /* See what we need to return. We can only return a 1, -1, or the | |
2870 | sign bit. */ | |
2871 | ||
2872 | if (normalizep == 0) | |
2873 | { | |
2874 | if (STORE_FLAG_VALUE == 1 || STORE_FLAG_VALUE == -1) | |
2875 | normalizep = STORE_FLAG_VALUE; | |
2876 | ||
2877 | else if (GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_INT | |
2878 | && STORE_FLAG_VALUE == 1 << (GET_MODE_BITSIZE (mode) - 1)) | |
2879 | ; | |
2880 | else | |
2881 | return 0; | |
2882 | } | |
2883 | ||
2884 | /* Try to put the result of the comparison in the sign bit. Assume we can't | |
2885 | do the necessary operation below. */ | |
2886 | ||
2887 | tem = 0; | |
2888 | ||
2889 | /* To see if A <= 0, compute (A | (A - 1)). A <= 0 iff that result has | |
2890 | the sign bit set. */ | |
2891 | ||
2892 | if (code == LE) | |
2893 | { | |
2894 | /* This is destructive, so SUBTARGET can't be OP0. */ | |
2895 | if (rtx_equal_p (subtarget, op0)) | |
2896 | subtarget = 0; | |
2897 | ||
2898 | tem = expand_binop (mode, sub_optab, op0, const1_rtx, subtarget, 0, | |
2899 | OPTAB_WIDEN); | |
2900 | if (tem) | |
2901 | tem = expand_binop (mode, ior_optab, op0, tem, subtarget, 0, | |
2902 | OPTAB_WIDEN); | |
2903 | } | |
2904 | ||
2905 | /* To see if A > 0, compute (((signed) A) << BITS) - A, where BITS is the | |
2906 | number of bits in the mode of OP0, minus one. */ | |
2907 | ||
2908 | if (code == GT) | |
2909 | { | |
2910 | if (rtx_equal_p (subtarget, op0)) | |
2911 | subtarget = 0; | |
2912 | ||
2913 | tem = expand_shift (RSHIFT_EXPR, mode, op0, | |
2914 | size_int (GET_MODE_BITSIZE (mode) - 1), | |
2915 | subtarget, 0); | |
2916 | tem = expand_binop (mode, sub_optab, tem, op0, subtarget, 0, | |
2917 | OPTAB_WIDEN); | |
2918 | } | |
2919 | ||
2920 | if (code == EQ || code == NE) | |
2921 | { | |
2922 | /* For EQ or NE, one way to do the comparison is to apply an operation | |
2923 | that converts the operand into a positive number if it is non-zero | |
2924 | or zero if it was originally zero. Then, for EQ, we subtract 1 and | |
2925 | for NE we negate. This puts the result in the sign bit. Then we | |
2926 | normalize with a shift, if needed. | |
2927 | ||
2928 | Two operations that can do the above actions are ABS and FFS, so try | |
2929 | them. If that doesn't work, and MODE is smaller than a full word, | |
36d747f6 | 2930 | we can use zero-extension to the wider mode (an unsigned conversion) |
44037a66 TG |
2931 | as the operation. */ |
2932 | ||
2933 | if (abs_optab->handlers[(int) mode].insn_code != CODE_FOR_nothing) | |
2934 | tem = expand_unop (mode, abs_optab, op0, subtarget, 1); | |
2935 | else if (ffs_optab->handlers[(int) mode].insn_code != CODE_FOR_nothing) | |
2936 | tem = expand_unop (mode, ffs_optab, op0, subtarget, 1); | |
2937 | else if (GET_MODE_SIZE (mode) < UNITS_PER_WORD) | |
2938 | { | |
2939 | mode = word_mode; | |
2940 | tem = convert_to_mode (mode, op0, 1); | |
2941 | } | |
2942 | ||
2943 | if (tem != 0) | |
2944 | { | |
2945 | if (code == EQ) | |
2946 | tem = expand_binop (mode, sub_optab, tem, const1_rtx, subtarget, | |
2947 | 0, OPTAB_WIDEN); | |
2948 | else | |
2949 | tem = expand_unop (mode, neg_optab, tem, subtarget, 0); | |
2950 | } | |
2951 | ||
2952 | /* If we couldn't do it that way, for NE we can "or" the two's complement | |
2953 | of the value with itself. For EQ, we take the one's complement of | |
2954 | that "or", which is an extra insn, so we only handle EQ if branches | |
2955 | are expensive. */ | |
2956 | ||
2957 | if (tem == 0 && (code == NE || BRANCH_COST > 1)) | |
2958 | { | |
36d747f6 RS |
2959 | if (rtx_equal_p (subtarget, op0)) |
2960 | subtarget = 0; | |
2961 | ||
44037a66 TG |
2962 | tem = expand_unop (mode, neg_optab, op0, subtarget, 0); |
2963 | tem = expand_binop (mode, ior_optab, tem, op0, subtarget, 0, | |
2964 | OPTAB_WIDEN); | |
2965 | ||
2966 | if (tem && code == EQ) | |
2967 | tem = expand_unop (mode, one_cmpl_optab, tem, subtarget, 0); | |
2968 | } | |
2969 | } | |
2970 | ||
2971 | if (tem && normalizep) | |
2972 | tem = expand_shift (RSHIFT_EXPR, mode, tem, | |
2973 | size_int (GET_MODE_BITSIZE (mode) - 1), | |
2974 | tem, normalizep == 1); | |
2975 | ||
2976 | if (tem && GET_MODE (tem) != target_mode) | |
2977 | { | |
2978 | convert_move (target, tem, 0); | |
2979 | tem = target; | |
2980 | } | |
2981 | ||
2982 | if (tem == 0) | |
2983 | delete_insns_since (last); | |
2984 | ||
2985 | return tem; | |
2986 | } | |
2987 | emit_jump_insn ((*bcc_gen_fctn[(int) code]) (label)); | |
2988 | emit_move_insn (target, const1_rtx); | |
2989 | emit_label (label); | |
2990 | ||
2991 | return target; | |
2992 | } |