1 /* Convert tree expression to rtl instructions, for GNU compiler.
2 Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
3 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
24 #include "coretypes.h"
30 #include "insn-config.h"
31 #include "insn-attr.h"
32 /* Include expr.h after insn-config.h so we get HAVE_conditional_move. */
35 #include "langhooks.h"
38 static bool prefer_and_bit_test (enum machine_mode, int);
39 static void do_jump_by_parts_greater (tree, int, rtx, rtx);
40 static void do_jump_by_parts_equality (tree, rtx, rtx);
41 static void do_compare_and_jump (tree, enum rtx_code, enum rtx_code, rtx,
44 /* At the start of a function, record that we have no previously-pushed
45 arguments waiting to be popped. */
48 init_pending_stack_adjust (void)
50 pending_stack_adjust = 0;
53 /* Discard any pending stack adjustment. This avoid relying on the
54 RTL optimizers to remove useless adjustments when we know the
55 stack pointer value is dead. */
57 discard_pending_stack_adjust (void)
59 stack_pointer_delta -= pending_stack_adjust;
60 pending_stack_adjust = 0;
63 /* When exiting from function, if safe, clear out any pending stack adjust
64 so the adjustment won't get done.
66 Note, if the current function calls alloca, then it must have a
67 frame pointer regardless of the value of flag_omit_frame_pointer. */
70 clear_pending_stack_adjust (void)
73 && (! flag_omit_frame_pointer || cfun->calls_alloca)
75 discard_pending_stack_adjust ();
78 /* Pop any previously-pushed arguments that have not been popped yet. */
81 do_pending_stack_adjust (void)
83 if (inhibit_defer_pop == 0)
85 if (pending_stack_adjust != 0)
86 adjust_stack (GEN_INT (pending_stack_adjust));
87 pending_stack_adjust = 0;
91 /* Expand conditional expressions. */
93 /* Generate code to evaluate EXP and jump to LABEL if the value is zero.
94 LABEL is an rtx of code CODE_LABEL, in this function and all the
98 jumpifnot (tree exp, rtx label)
100 do_jump (exp, label, NULL_RTX);
103 /* Generate code to evaluate EXP and jump to LABEL if the value is nonzero. */
106 jumpif (tree exp, rtx label)
108 do_jump (exp, NULL_RTX, label);
111 /* Used internally by prefer_and_bit_test. */
113 static GTY(()) rtx and_reg;
114 static GTY(()) rtx and_test;
115 static GTY(()) rtx shift_test;
117 /* Compare the relative costs of "(X & (1 << BITNUM))" and "(X >> BITNUM) & 1",
118 where X is an arbitrary register of mode MODE. Return true if the former
122 prefer_and_bit_test (enum machine_mode mode, int bitnum)
126 /* Set up rtxes for the two variations. Use NULL as a placeholder
127 for the BITNUM-based constants. */
128 and_reg = gen_rtx_REG (mode, FIRST_PSEUDO_REGISTER);
129 and_test = gen_rtx_AND (mode, and_reg, NULL);
130 shift_test = gen_rtx_AND (mode, gen_rtx_ASHIFTRT (mode, and_reg, NULL),
135 /* Change the mode of the previously-created rtxes. */
136 PUT_MODE (and_reg, mode);
137 PUT_MODE (and_test, mode);
138 PUT_MODE (shift_test, mode);
139 PUT_MODE (XEXP (shift_test, 0), mode);
142 /* Fill in the integers. */
143 XEXP (and_test, 1) = GEN_INT ((unsigned HOST_WIDE_INT) 1 << bitnum);
144 XEXP (XEXP (shift_test, 0), 1) = GEN_INT (bitnum);
146 return (rtx_cost (and_test, IF_THEN_ELSE)
147 <= rtx_cost (shift_test, IF_THEN_ELSE));
150 /* Generate code to evaluate EXP and jump to IF_FALSE_LABEL if
151 the result is zero, or IF_TRUE_LABEL if the result is one.
152 Either of IF_FALSE_LABEL and IF_TRUE_LABEL may be zero,
153 meaning fall through in that case.
155 do_jump always does any pending stack adjust except when it does not
156 actually perform a jump. An example where there is no jump
157 is when EXP is `(foo (), 0)' and IF_FALSE_LABEL is null. */
160 do_jump (tree exp, rtx if_false_label, rtx if_true_label)
162 enum tree_code code = TREE_CODE (exp);
166 enum machine_mode mode;
167 rtx drop_through_label = 0;
175 temp = integer_zerop (exp) ? if_false_label : if_true_label;
181 /* This is not true with #pragma weak */
183 /* The address of something can never be zero. */
185 emit_jump (if_true_label);
190 if (TREE_CODE (TREE_OPERAND (exp, 0)) == COMPONENT_REF
191 || TREE_CODE (TREE_OPERAND (exp, 0)) == BIT_FIELD_REF
192 || TREE_CODE (TREE_OPERAND (exp, 0)) == ARRAY_REF
193 || TREE_CODE (TREE_OPERAND (exp, 0)) == ARRAY_RANGE_REF)
196 /* If we are narrowing the operand, we have to do the compare in the
198 if ((TYPE_PRECISION (TREE_TYPE (exp))
199 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0)))))
201 case NON_LVALUE_EXPR:
206 /* These cannot change zero->nonzero or vice versa. */
207 do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label);
211 /* fold_single_bit_test() converts (X & (1 << C)) into (X >> C) & 1.
212 See if the former is preferred for jump tests and restore it
214 if (integer_onep (TREE_OPERAND (exp, 1)))
216 tree exp0 = TREE_OPERAND (exp, 0);
217 rtx set_label, clr_label;
219 /* Strip narrowing integral type conversions. */
220 while (CONVERT_EXPR_P (exp0)
221 && TREE_OPERAND (exp0, 0) != error_mark_node
222 && TYPE_PRECISION (TREE_TYPE (exp0))
223 <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp0, 0))))
224 exp0 = TREE_OPERAND (exp0, 0);
226 /* "exp0 ^ 1" inverts the sense of the single bit test. */
227 if (TREE_CODE (exp0) == BIT_XOR_EXPR
228 && integer_onep (TREE_OPERAND (exp0, 1)))
230 exp0 = TREE_OPERAND (exp0, 0);
231 clr_label = if_true_label;
232 set_label = if_false_label;
236 clr_label = if_false_label;
237 set_label = if_true_label;
240 if (TREE_CODE (exp0) == RSHIFT_EXPR)
242 tree arg = TREE_OPERAND (exp0, 0);
243 tree shift = TREE_OPERAND (exp0, 1);
244 tree argtype = TREE_TYPE (arg);
245 if (TREE_CODE (shift) == INTEGER_CST
246 && compare_tree_int (shift, 0) >= 0
247 && compare_tree_int (shift, HOST_BITS_PER_WIDE_INT) < 0
248 && prefer_and_bit_test (TYPE_MODE (argtype),
249 TREE_INT_CST_LOW (shift)))
251 HOST_WIDE_INT mask = (HOST_WIDE_INT) 1
252 << TREE_INT_CST_LOW (shift);
253 do_jump (build2 (BIT_AND_EXPR, argtype, arg,
254 build_int_cst_type (argtype, mask)),
255 clr_label, set_label);
261 /* If we are AND'ing with a small constant, do this comparison in the
262 smallest type that fits. If the machine doesn't have comparisons
263 that small, it will be converted back to the wider comparison.
264 This helps if we are testing the sign bit of a narrower object.
265 combine can't do this for us because it can't know whether a
266 ZERO_EXTRACT or a compare in a smaller mode exists, but we do. */
268 if (! SLOW_BYTE_ACCESS
269 && TREE_CODE (TREE_OPERAND (exp, 1)) == INTEGER_CST
270 && TYPE_PRECISION (TREE_TYPE (exp)) <= HOST_BITS_PER_WIDE_INT
271 && (i = tree_floor_log2 (TREE_OPERAND (exp, 1))) >= 0
272 && (mode = mode_for_size (i + 1, MODE_INT, 0)) != BLKmode
273 && (type = lang_hooks.types.type_for_mode (mode, 1)) != 0
274 && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (exp))
275 && (optab_handler (cmp_optab, TYPE_MODE (type))->insn_code
276 != CODE_FOR_nothing))
278 do_jump (fold_convert (type, exp), if_false_label, if_true_label);
284 do_jump (TREE_OPERAND (exp, 0), if_true_label, if_false_label);
289 rtx label1 = gen_label_rtx ();
290 if (!if_true_label || !if_false_label)
292 drop_through_label = gen_label_rtx ();
294 if_true_label = drop_through_label;
296 if_false_label = drop_through_label;
299 do_pending_stack_adjust ();
300 do_jump (TREE_OPERAND (exp, 0), label1, NULL_RTX);
301 do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label);
303 do_jump (TREE_OPERAND (exp, 2), if_false_label, if_true_label);
308 /* Lowered by gimplify.c. */
314 case ARRAY_RANGE_REF:
316 HOST_WIDE_INT bitsize, bitpos;
318 enum machine_mode mode;
323 /* Get description of this reference. We don't actually care
324 about the underlying object here. */
325 get_inner_reference (exp, &bitsize, &bitpos, &offset, &mode,
326 &unsignedp, &volatilep, false);
328 type = lang_hooks.types.type_for_size (bitsize, unsignedp);
329 if (! SLOW_BYTE_ACCESS
330 && type != 0 && bitsize >= 0
331 && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (exp))
332 && (optab_handler (cmp_optab, TYPE_MODE (type))->insn_code
333 != CODE_FOR_nothing))
335 do_jump (fold_convert (type, exp), if_false_label, if_true_label);
343 tree inner_type = TREE_TYPE (TREE_OPERAND (exp, 0));
345 gcc_assert (GET_MODE_CLASS (TYPE_MODE (inner_type))
346 != MODE_COMPLEX_FLOAT);
347 gcc_assert (GET_MODE_CLASS (TYPE_MODE (inner_type))
348 != MODE_COMPLEX_INT);
350 if (integer_zerop (TREE_OPERAND (exp, 1)))
351 do_jump (TREE_OPERAND (exp, 0), if_true_label, if_false_label);
352 else if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_INT
353 && !can_compare_p (EQ, TYPE_MODE (inner_type), ccp_jump))
354 do_jump_by_parts_equality (exp, if_false_label, if_true_label);
356 do_compare_and_jump (exp, EQ, EQ, if_false_label, if_true_label);
361 /* Nonzero iff operands of minus differ. */
362 exp = build2 (NE_EXPR, TREE_TYPE (exp),
363 TREE_OPERAND (exp, 0),
364 TREE_OPERAND (exp, 1));
368 tree inner_type = TREE_TYPE (TREE_OPERAND (exp, 0));
370 gcc_assert (GET_MODE_CLASS (TYPE_MODE (inner_type))
371 != MODE_COMPLEX_FLOAT);
372 gcc_assert (GET_MODE_CLASS (TYPE_MODE (inner_type))
373 != MODE_COMPLEX_INT);
375 if (integer_zerop (TREE_OPERAND (exp, 1)))
376 do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label);
377 else if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_INT
378 && !can_compare_p (NE, TYPE_MODE (inner_type), ccp_jump))
379 do_jump_by_parts_equality (exp, if_true_label, if_false_label);
381 do_compare_and_jump (exp, NE, NE, if_false_label, if_true_label);
386 mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
387 if (GET_MODE_CLASS (mode) == MODE_INT
388 && ! can_compare_p (LT, mode, ccp_jump))
389 do_jump_by_parts_greater (exp, 1, if_false_label, if_true_label);
391 do_compare_and_jump (exp, LT, LTU, if_false_label, if_true_label);
395 mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
396 if (GET_MODE_CLASS (mode) == MODE_INT
397 && ! can_compare_p (LE, mode, ccp_jump))
398 do_jump_by_parts_greater (exp, 0, if_true_label, if_false_label);
400 do_compare_and_jump (exp, LE, LEU, if_false_label, if_true_label);
404 mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
405 if (GET_MODE_CLASS (mode) == MODE_INT
406 && ! can_compare_p (GT, mode, ccp_jump))
407 do_jump_by_parts_greater (exp, 0, if_false_label, if_true_label);
409 do_compare_and_jump (exp, GT, GTU, if_false_label, if_true_label);
413 mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
414 if (GET_MODE_CLASS (mode) == MODE_INT
415 && ! can_compare_p (GE, mode, ccp_jump))
416 do_jump_by_parts_greater (exp, 1, if_true_label, if_false_label);
418 do_compare_and_jump (exp, GE, GEU, if_false_label, if_true_label);
424 enum rtx_code cmp, rcmp;
427 if (code == UNORDERED_EXPR)
428 cmp = UNORDERED, rcmp = ORDERED;
430 cmp = ORDERED, rcmp = UNORDERED;
431 mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
434 if (! can_compare_p (cmp, mode, ccp_jump)
435 && (can_compare_p (rcmp, mode, ccp_jump)
436 /* If the target doesn't provide either UNORDERED or ORDERED
437 comparisons, canonicalize on UNORDERED for the library. */
438 || rcmp == UNORDERED))
442 do_compare_and_jump (exp, cmp, cmp, if_false_label, if_true_label);
444 do_compare_and_jump (exp, rcmp, rcmp, if_true_label, if_false_label);
449 enum rtx_code rcode1;
450 enum tree_code tcode1, tcode2;
454 tcode1 = UNORDERED_EXPR;
459 tcode1 = UNORDERED_EXPR;
464 tcode1 = UNORDERED_EXPR;
469 tcode1 = UNORDERED_EXPR;
474 tcode1 = UNORDERED_EXPR;
478 /* It is ok for LTGT_EXPR to trap when the result is unordered,
479 so expand to (a < b) || (a > b). */
486 mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
487 if (can_compare_p (rcode1, mode, ccp_jump))
488 do_compare_and_jump (exp, rcode1, rcode1, if_false_label,
492 tree op0 = save_expr (TREE_OPERAND (exp, 0));
493 tree op1 = save_expr (TREE_OPERAND (exp, 1));
496 /* If the target doesn't support combined unordered
497 compares, decompose into two comparisons. */
498 if (if_true_label == 0)
499 drop_through_label = if_true_label = gen_label_rtx ();
501 cmp0 = fold_build2 (tcode1, TREE_TYPE (exp), op0, op1);
502 cmp1 = fold_build2 (tcode2, TREE_TYPE (exp), op0, op1);
503 do_jump (cmp0, 0, if_true_label);
504 do_jump (cmp1, if_false_label, if_true_label);
510 /* High branch cost, expand as the bitwise AND of the conditions.
511 Do the same if the RHS has side effects, because we're effectively
512 turning a TRUTH_AND_EXPR into a TRUTH_ANDIF_EXPR. */
513 if (BRANCH_COST (optimize_insn_for_speed_p (),
515 || TREE_SIDE_EFFECTS (TREE_OPERAND (exp, 1)))
518 case TRUTH_ANDIF_EXPR:
519 if (if_false_label == NULL_RTX)
521 drop_through_label = gen_label_rtx ();
522 do_jump (TREE_OPERAND (exp, 0), drop_through_label, NULL_RTX);
523 do_jump (TREE_OPERAND (exp, 1), NULL_RTX, if_true_label);
527 do_jump (TREE_OPERAND (exp, 0), if_false_label, NULL_RTX);
528 do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label);
533 /* High branch cost, expand as the bitwise OR of the conditions.
534 Do the same if the RHS has side effects, because we're effectively
535 turning a TRUTH_OR_EXPR into a TRUTH_ORIF_EXPR. */
536 if (BRANCH_COST (optimize_insn_for_speed_p (), false)>= 4
537 || TREE_SIDE_EFFECTS (TREE_OPERAND (exp, 1)))
540 case TRUTH_ORIF_EXPR:
541 if (if_true_label == NULL_RTX)
543 drop_through_label = gen_label_rtx ();
544 do_jump (TREE_OPERAND (exp, 0), NULL_RTX, drop_through_label);
545 do_jump (TREE_OPERAND (exp, 1), if_false_label, NULL_RTX);
549 do_jump (TREE_OPERAND (exp, 0), NULL_RTX, if_true_label);
550 do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label);
554 /* Fall through and generate the normal code. */
557 temp = expand_normal (exp);
558 do_pending_stack_adjust ();
559 /* The RTL optimizers prefer comparisons against pseudos. */
560 if (GET_CODE (temp) == SUBREG)
562 /* Compare promoted variables in their promoted mode. */
563 if (SUBREG_PROMOTED_VAR_P (temp)
564 && REG_P (XEXP (temp, 0)))
565 temp = XEXP (temp, 0);
567 temp = copy_to_reg (temp);
569 do_compare_rtx_and_jump (temp, CONST0_RTX (GET_MODE (temp)),
570 NE, TYPE_UNSIGNED (TREE_TYPE (exp)),
571 GET_MODE (temp), NULL_RTX,
572 if_false_label, if_true_label);
575 if (drop_through_label)
577 do_pending_stack_adjust ();
578 emit_label (drop_through_label);
582 /* Compare OP0 with OP1, word at a time, in mode MODE.
583 UNSIGNEDP says to do unsigned comparison.
584 Jump to IF_TRUE_LABEL if OP0 is greater, IF_FALSE_LABEL otherwise. */
587 do_jump_by_parts_greater_rtx (enum machine_mode mode, int unsignedp, rtx op0,
588 rtx op1, rtx if_false_label, rtx if_true_label)
590 int nwords = (GET_MODE_SIZE (mode) / UNITS_PER_WORD);
591 rtx drop_through_label = 0;
594 if (! if_true_label || ! if_false_label)
595 drop_through_label = gen_label_rtx ();
597 if_true_label = drop_through_label;
598 if (! if_false_label)
599 if_false_label = drop_through_label;
601 /* Compare a word at a time, high order first. */
602 for (i = 0; i < nwords; i++)
604 rtx op0_word, op1_word;
606 if (WORDS_BIG_ENDIAN)
608 op0_word = operand_subword_force (op0, i, mode);
609 op1_word = operand_subword_force (op1, i, mode);
613 op0_word = operand_subword_force (op0, nwords - 1 - i, mode);
614 op1_word = operand_subword_force (op1, nwords - 1 - i, mode);
617 /* All but high-order word must be compared as unsigned. */
618 do_compare_rtx_and_jump (op0_word, op1_word, GT,
619 (unsignedp || i > 0), word_mode, NULL_RTX,
620 NULL_RTX, if_true_label);
622 /* Consider lower words only if these are equal. */
623 do_compare_rtx_and_jump (op0_word, op1_word, NE, unsignedp, word_mode,
624 NULL_RTX, NULL_RTX, if_false_label);
628 emit_jump (if_false_label);
629 if (drop_through_label)
630 emit_label (drop_through_label);
633 /* Given a comparison expression EXP for values too wide to be compared
634 with one insn, test the comparison and jump to the appropriate label.
635 The code of EXP is ignored; we always test GT if SWAP is 0,
636 and LT if SWAP is 1. */
639 do_jump_by_parts_greater (tree exp, int swap, rtx if_false_label,
642 rtx op0 = expand_normal (TREE_OPERAND (exp, swap));
643 rtx op1 = expand_normal (TREE_OPERAND (exp, !swap));
644 enum machine_mode mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
645 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp, 0)));
647 do_jump_by_parts_greater_rtx (mode, unsignedp, op0, op1, if_false_label,
651 /* Jump according to whether OP0 is 0. We assume that OP0 has an integer
652 mode, MODE, that is too wide for the available compare insns. Either
653 Either (but not both) of IF_TRUE_LABEL and IF_FALSE_LABEL may be NULL_RTX
654 to indicate drop through. */
657 do_jump_by_parts_zero_rtx (enum machine_mode mode, rtx op0,
658 rtx if_false_label, rtx if_true_label)
660 int nwords = GET_MODE_SIZE (mode) / UNITS_PER_WORD;
663 rtx drop_through_label = 0;
665 /* The fastest way of doing this comparison on almost any machine is to
666 "or" all the words and compare the result. If all have to be loaded
667 from memory and this is a very wide item, it's possible this may
668 be slower, but that's highly unlikely. */
670 part = gen_reg_rtx (word_mode);
671 emit_move_insn (part, operand_subword_force (op0, 0, GET_MODE (op0)));
672 for (i = 1; i < nwords && part != 0; i++)
673 part = expand_binop (word_mode, ior_optab, part,
674 operand_subword_force (op0, i, GET_MODE (op0)),
675 part, 1, OPTAB_WIDEN);
679 do_compare_rtx_and_jump (part, const0_rtx, EQ, 1, word_mode,
680 NULL_RTX, if_false_label, if_true_label);
685 /* If we couldn't do the "or" simply, do this with a series of compares. */
686 if (! if_false_label)
687 drop_through_label = if_false_label = gen_label_rtx ();
689 for (i = 0; i < nwords; i++)
690 do_compare_rtx_and_jump (operand_subword_force (op0, i, GET_MODE (op0)),
691 const0_rtx, EQ, 1, word_mode, NULL_RTX,
692 if_false_label, NULL_RTX);
695 emit_jump (if_true_label);
697 if (drop_through_label)
698 emit_label (drop_through_label);
701 /* Test for the equality of two RTX expressions OP0 and OP1 in mode MODE,
702 where MODE is an integer mode too wide to be compared with one insn.
703 Either (but not both) of IF_TRUE_LABEL and IF_FALSE_LABEL may be NULL_RTX
704 to indicate drop through. */
707 do_jump_by_parts_equality_rtx (enum machine_mode mode, rtx op0, rtx op1,
708 rtx if_false_label, rtx if_true_label)
710 int nwords = (GET_MODE_SIZE (mode) / UNITS_PER_WORD);
711 rtx drop_through_label = 0;
714 if (op1 == const0_rtx)
716 do_jump_by_parts_zero_rtx (mode, op0, if_false_label, if_true_label);
719 else if (op0 == const0_rtx)
721 do_jump_by_parts_zero_rtx (mode, op1, if_false_label, if_true_label);
725 if (! if_false_label)
726 drop_through_label = if_false_label = gen_label_rtx ();
728 for (i = 0; i < nwords; i++)
729 do_compare_rtx_and_jump (operand_subword_force (op0, i, mode),
730 operand_subword_force (op1, i, mode),
731 EQ, 0, word_mode, NULL_RTX,
732 if_false_label, NULL_RTX);
735 emit_jump (if_true_label);
736 if (drop_through_label)
737 emit_label (drop_through_label);
740 /* Given an EQ_EXPR expression EXP for values too wide to be compared
741 with one insn, test the comparison and jump to the appropriate label. */
744 do_jump_by_parts_equality (tree exp, rtx if_false_label, rtx if_true_label)
746 rtx op0 = expand_normal (TREE_OPERAND (exp, 0));
747 rtx op1 = expand_normal (TREE_OPERAND (exp, 1));
748 enum machine_mode mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
749 do_jump_by_parts_equality_rtx (mode, op0, op1, if_false_label,
753 /* Generate code for a comparison of OP0 and OP1 with rtx code CODE.
754 MODE is the machine mode of the comparison, not of the result.
755 (including code to compute the values to be compared) and set CC0
756 according to the result. The decision as to signed or unsigned
757 comparison must be made by the caller.
759 We force a stack adjustment unless there are currently
760 things pushed on the stack that aren't yet used.
762 If MODE is BLKmode, SIZE is an RTX giving the size of the objects being
766 compare_from_rtx (rtx op0, rtx op1, enum rtx_code code, int unsignedp,
767 enum machine_mode mode, rtx size)
771 /* If one operand is constant, make it the second one. Only do this
772 if the other operand is not constant as well. */
774 if (swap_commutative_operands_p (op0, op1))
779 code = swap_condition (code);
782 do_pending_stack_adjust ();
784 code = unsignedp ? unsigned_condition (code) : code;
785 tem = simplify_relational_operation (code, VOIDmode, mode, op0, op1);
788 if (CONSTANT_P (tem))
791 if (COMPARISON_P (tem))
793 code = GET_CODE (tem);
796 mode = GET_MODE (op0);
797 unsignedp = (code == GTU || code == LTU
798 || code == GEU || code == LEU);
802 emit_cmp_insn (op0, op1, code, size, mode, unsignedp);
805 return gen_rtx_fmt_ee (code, VOIDmode, cc0_rtx, const0_rtx);
807 return gen_rtx_fmt_ee (code, VOIDmode, op0, op1);
811 /* Like do_compare_and_jump but expects the values to compare as two rtx's.
812 The decision as to signed or unsigned comparison must be made by the caller.
814 If MODE is BLKmode, SIZE is an RTX giving the size of the objects being
818 do_compare_rtx_and_jump (rtx op0, rtx op1, enum rtx_code code, int unsignedp,
819 enum machine_mode mode, rtx size, rtx if_false_label,
823 int dummy_true_label = 0;
825 /* Reverse the comparison if that is safe and we want to jump if it is
827 if (! if_true_label && ! FLOAT_MODE_P (mode))
829 if_true_label = if_false_label;
831 code = reverse_condition (code);
834 /* If one operand is constant, make it the second one. Only do this
835 if the other operand is not constant as well. */
837 if (swap_commutative_operands_p (op0, op1))
842 code = swap_condition (code);
845 do_pending_stack_adjust ();
847 code = unsignedp ? unsigned_condition (code) : code;
848 if (0 != (tem = simplify_relational_operation (code, mode, VOIDmode,
851 if (CONSTANT_P (tem))
853 rtx label = (tem == const0_rtx || tem == CONST0_RTX (mode))
854 ? if_false_label : if_true_label;
860 code = GET_CODE (tem);
861 mode = GET_MODE (tem);
864 unsignedp = (code == GTU || code == LTU || code == GEU || code == LEU);
870 dummy_true_label = 1;
871 if_true_label = gen_label_rtx ();
874 if (GET_MODE_CLASS (mode) == MODE_INT
875 && ! can_compare_p (code, mode, ccp_jump))
880 do_jump_by_parts_greater_rtx (mode, 1, op1, op0,
881 if_false_label, if_true_label);
885 do_jump_by_parts_greater_rtx (mode, 1, op0, op1,
886 if_true_label, if_false_label);
890 do_jump_by_parts_greater_rtx (mode, 1, op0, op1,
891 if_false_label, if_true_label);
895 do_jump_by_parts_greater_rtx (mode, 1, op1, op0,
896 if_true_label, if_false_label);
900 do_jump_by_parts_greater_rtx (mode, 0, op1, op0,
901 if_false_label, if_true_label);
905 do_jump_by_parts_greater_rtx (mode, 0, op0, op1,
906 if_true_label, if_false_label);
910 do_jump_by_parts_greater_rtx (mode, 0, op0, op1,
911 if_false_label, if_true_label);
915 do_jump_by_parts_greater_rtx (mode, 0, op1, op0,
916 if_true_label, if_false_label);
920 do_jump_by_parts_equality_rtx (mode, op0, op1, if_false_label,
925 do_jump_by_parts_equality_rtx (mode, op0, op1, if_true_label,
934 emit_cmp_and_jump_insns (op0, op1, code, size, mode, unsignedp,
938 emit_jump (if_false_label);
939 if (dummy_true_label)
940 emit_label (if_true_label);
943 /* Generate code for a comparison expression EXP (including code to compute
944 the values to be compared) and a conditional jump to IF_FALSE_LABEL and/or
945 IF_TRUE_LABEL. One of the labels can be NULL_RTX, in which case the
946 generated code will drop through.
947 SIGNED_CODE should be the rtx operation for this comparison for
948 signed data; UNSIGNED_CODE, likewise for use if data is unsigned.
950 We force a stack adjustment unless there are currently
951 things pushed on the stack that aren't yet used. */
954 do_compare_and_jump (tree exp, enum rtx_code signed_code,
955 enum rtx_code unsigned_code, rtx if_false_label,
960 enum machine_mode mode;
964 /* Don't crash if the comparison was erroneous. */
965 op0 = expand_normal (TREE_OPERAND (exp, 0));
966 if (TREE_CODE (TREE_OPERAND (exp, 0)) == ERROR_MARK)
969 op1 = expand_normal (TREE_OPERAND (exp, 1));
970 if (TREE_CODE (TREE_OPERAND (exp, 1)) == ERROR_MARK)
973 type = TREE_TYPE (TREE_OPERAND (exp, 0));
974 mode = TYPE_MODE (type);
975 if (TREE_CODE (TREE_OPERAND (exp, 0)) == INTEGER_CST
976 && (TREE_CODE (TREE_OPERAND (exp, 1)) != INTEGER_CST
977 || (GET_MODE_BITSIZE (mode)
978 > GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp,
981 /* op0 might have been replaced by promoted constant, in which
982 case the type of second argument should be used. */
983 type = TREE_TYPE (TREE_OPERAND (exp, 1));
984 mode = TYPE_MODE (type);
986 unsignedp = TYPE_UNSIGNED (type);
987 code = unsignedp ? unsigned_code : signed_code;
989 #ifdef HAVE_canonicalize_funcptr_for_compare
990 /* If function pointers need to be "canonicalized" before they can
991 be reliably compared, then canonicalize them.
992 Only do this if *both* sides of the comparison are function pointers.
993 If one side isn't, we want a noncanonicalized comparison. See PR
995 if (HAVE_canonicalize_funcptr_for_compare
996 && TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == POINTER_TYPE
997 && TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
999 && TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 1))) == POINTER_TYPE
1000 && TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 1))))
1003 rtx new_op0 = gen_reg_rtx (mode);
1004 rtx new_op1 = gen_reg_rtx (mode);
1006 emit_insn (gen_canonicalize_funcptr_for_compare (new_op0, op0));
1009 emit_insn (gen_canonicalize_funcptr_for_compare (new_op1, op1));
1014 do_compare_rtx_and_jump (op0, op1, code, unsignedp, mode,
1016 ? expr_size (TREE_OPERAND (exp, 0)) : NULL_RTX),
1017 if_false_label, if_true_label);
1020 #include "gt-dojump.h"