1 /* Support routines for Value Range Propagation (VRP).
2 Copyright (C) 2005-2017 Free Software Foundation, Inc.
3 Contributed by Diego Novillo <dnovillo@redhat.com>.
5 This file is part of GCC.
7 GCC 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 3, or (at your option)
12 GCC 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.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
23 #include "coretypes.h"
25 #include "insn-codes.h"
30 #include "tree-pass.h"
32 #include "optabs-tree.h"
33 #include "gimple-pretty-print.h"
34 #include "diagnostic-core.h"
36 #include "fold-const.h"
37 #include "stor-layout.h"
40 #include "gimple-fold.h"
42 #include "gimple-iterator.h"
43 #include "gimple-walk.h"
45 #include "tree-ssa-loop-manip.h"
46 #include "tree-ssa-loop-niter.h"
47 #include "tree-ssa-loop.h"
48 #include "tree-into-ssa.h"
52 #include "tree-scalar-evolution.h"
53 #include "tree-ssa-propagate.h"
54 #include "tree-chrec.h"
55 #include "tree-ssa-threadupdate.h"
56 #include "tree-ssa-scopedtables.h"
57 #include "tree-ssa-threadedge.h"
58 #include "omp-general.h"
60 #include "case-cfn-macros.h"
62 #include "alloc-pool.h"
64 #include "tree-cfgcleanup.h"
65 #include "stringpool.h"
67 #include "vr-values.h"
69 /* Set of SSA names found live during the RPO traversal of the function
70 for still active basic-blocks. */
73 /* Return true if the SSA name NAME is live on the edge E. */
76 live_on_edge (edge e
, tree name
)
78 return (live
[e
->dest
->index
]
79 && bitmap_bit_p (live
[e
->dest
->index
], SSA_NAME_VERSION (name
)));
82 /* Local functions. */
83 static int compare_values (tree val1
, tree val2
);
84 static int compare_values_warnv (tree val1
, tree val2
, bool *);
86 /* Location information for ASSERT_EXPRs. Each instance of this
87 structure describes an ASSERT_EXPR for an SSA name. Since a single
88 SSA name may have more than one assertion associated with it, these
89 locations are kept in a linked list attached to the corresponding
93 /* Basic block where the assertion would be inserted. */
96 /* Some assertions need to be inserted on an edge (e.g., assertions
97 generated by COND_EXPRs). In those cases, BB will be NULL. */
100 /* Pointer to the statement that generated this assertion. */
101 gimple_stmt_iterator si
;
103 /* Predicate code for the ASSERT_EXPR. Must be COMPARISON_CLASS_P. */
104 enum tree_code comp_code
;
106 /* Value being compared against. */
109 /* Expression to compare. */
112 /* Next node in the linked list. */
116 /* If bit I is present, it means that SSA name N_i has a list of
117 assertions that should be inserted in the IL. */
118 static bitmap need_assert_for
;
120 /* Array of locations lists where to insert assertions. ASSERTS_FOR[I]
121 holds a list of ASSERT_LOCUS_T nodes that describe where
122 ASSERT_EXPRs for SSA name N_I should be inserted. */
123 static assert_locus
**asserts_for
;
125 struct switch_update
{
130 static vec
<edge
> to_remove_edges
;
131 static vec
<switch_update
> to_update_switch_stmts
;
134 /* Return the maximum value for TYPE. */
137 vrp_val_max (const_tree type
)
139 if (!INTEGRAL_TYPE_P (type
))
142 return TYPE_MAX_VALUE (type
);
145 /* Return the minimum value for TYPE. */
148 vrp_val_min (const_tree type
)
150 if (!INTEGRAL_TYPE_P (type
))
153 return TYPE_MIN_VALUE (type
);
156 /* Return whether VAL is equal to the maximum value of its type.
157 We can't do a simple equality comparison with TYPE_MAX_VALUE because
158 C typedefs and Ada subtypes can produce types whose TYPE_MAX_VALUE
159 is not == to the integer constant with the same value in the type. */
162 vrp_val_is_max (const_tree val
)
164 tree type_max
= vrp_val_max (TREE_TYPE (val
));
165 return (val
== type_max
166 || (type_max
!= NULL_TREE
167 && operand_equal_p (val
, type_max
, 0)));
170 /* Return whether VAL is equal to the minimum value of its type. */
173 vrp_val_is_min (const_tree val
)
175 tree type_min
= vrp_val_min (TREE_TYPE (val
));
176 return (val
== type_min
177 || (type_min
!= NULL_TREE
178 && operand_equal_p (val
, type_min
, 0)));
182 /* Set value range VR to VR_UNDEFINED. */
185 set_value_range_to_undefined (value_range
*vr
)
187 vr
->type
= VR_UNDEFINED
;
188 vr
->min
= vr
->max
= NULL_TREE
;
190 bitmap_clear (vr
->equiv
);
193 /* Set value range VR to VR_VARYING. */
196 set_value_range_to_varying (value_range
*vr
)
198 vr
->type
= VR_VARYING
;
199 vr
->min
= vr
->max
= NULL_TREE
;
201 bitmap_clear (vr
->equiv
);
204 /* Set value range VR to {T, MIN, MAX, EQUIV}. */
207 set_value_range (value_range
*vr
, enum value_range_type t
, tree min
,
208 tree max
, bitmap equiv
)
210 /* Check the validity of the range. */
212 && (t
== VR_RANGE
|| t
== VR_ANTI_RANGE
))
216 gcc_assert (min
&& max
);
218 gcc_assert (!TREE_OVERFLOW_P (min
) && !TREE_OVERFLOW_P (max
));
220 if (INTEGRAL_TYPE_P (TREE_TYPE (min
)) && t
== VR_ANTI_RANGE
)
221 gcc_assert (!vrp_val_is_min (min
) || !vrp_val_is_max (max
));
223 cmp
= compare_values (min
, max
);
224 gcc_assert (cmp
== 0 || cmp
== -1 || cmp
== -2);
228 && (t
== VR_UNDEFINED
|| t
== VR_VARYING
))
230 gcc_assert (min
== NULL_TREE
&& max
== NULL_TREE
);
231 gcc_assert (equiv
== NULL
|| bitmap_empty_p (equiv
));
238 /* Since updating the equivalence set involves deep copying the
239 bitmaps, only do it if absolutely necessary.
241 All equivalence bitmaps are allocated from the same obstack. So
242 we can use the obstack associated with EQUIV to allocate vr->equiv. */
243 if (vr
->equiv
== NULL
245 vr
->equiv
= BITMAP_ALLOC (equiv
->obstack
);
247 if (equiv
!= vr
->equiv
)
249 if (equiv
&& !bitmap_empty_p (equiv
))
250 bitmap_copy (vr
->equiv
, equiv
);
252 bitmap_clear (vr
->equiv
);
257 /* Set value range VR to the canonical form of {T, MIN, MAX, EQUIV}.
258 This means adjusting T, MIN and MAX representing the case of a
259 wrapping range with MAX < MIN covering [MIN, type_max] U [type_min, MAX]
260 as anti-rage ~[MAX+1, MIN-1]. Likewise for wrapping anti-ranges.
261 In corner cases where MAX+1 or MIN-1 wraps this will fall back
263 This routine exists to ease canonicalization in the case where we
264 extract ranges from var + CST op limit. */
267 set_and_canonicalize_value_range (value_range
*vr
, enum value_range_type t
,
268 tree min
, tree max
, bitmap equiv
)
270 /* Use the canonical setters for VR_UNDEFINED and VR_VARYING. */
271 if (t
== VR_UNDEFINED
)
273 set_value_range_to_undefined (vr
);
276 else if (t
== VR_VARYING
)
278 set_value_range_to_varying (vr
);
282 /* Nothing to canonicalize for symbolic ranges. */
283 if (TREE_CODE (min
) != INTEGER_CST
284 || TREE_CODE (max
) != INTEGER_CST
)
286 set_value_range (vr
, t
, min
, max
, equiv
);
290 /* Wrong order for min and max, to swap them and the VR type we need
292 if (tree_int_cst_lt (max
, min
))
296 /* For one bit precision if max < min, then the swapped
297 range covers all values, so for VR_RANGE it is varying and
298 for VR_ANTI_RANGE empty range, so drop to varying as well. */
299 if (TYPE_PRECISION (TREE_TYPE (min
)) == 1)
301 set_value_range_to_varying (vr
);
305 one
= build_int_cst (TREE_TYPE (min
), 1);
306 tmp
= int_const_binop (PLUS_EXPR
, max
, one
);
307 max
= int_const_binop (MINUS_EXPR
, min
, one
);
310 /* There's one corner case, if we had [C+1, C] before we now have
311 that again. But this represents an empty value range, so drop
312 to varying in this case. */
313 if (tree_int_cst_lt (max
, min
))
315 set_value_range_to_varying (vr
);
319 t
= t
== VR_RANGE
? VR_ANTI_RANGE
: VR_RANGE
;
322 /* Anti-ranges that can be represented as ranges should be so. */
323 if (t
== VR_ANTI_RANGE
)
325 bool is_min
= vrp_val_is_min (min
);
326 bool is_max
= vrp_val_is_max (max
);
328 if (is_min
&& is_max
)
330 /* We cannot deal with empty ranges, drop to varying.
331 ??? This could be VR_UNDEFINED instead. */
332 set_value_range_to_varying (vr
);
335 else if (TYPE_PRECISION (TREE_TYPE (min
)) == 1
336 && (is_min
|| is_max
))
338 /* Non-empty boolean ranges can always be represented
339 as a singleton range. */
341 min
= max
= vrp_val_max (TREE_TYPE (min
));
343 min
= max
= vrp_val_min (TREE_TYPE (min
));
347 /* As a special exception preserve non-null ranges. */
348 && !(TYPE_UNSIGNED (TREE_TYPE (min
))
349 && integer_zerop (max
)))
351 tree one
= build_int_cst (TREE_TYPE (max
), 1);
352 min
= int_const_binop (PLUS_EXPR
, max
, one
);
353 max
= vrp_val_max (TREE_TYPE (max
));
358 tree one
= build_int_cst (TREE_TYPE (min
), 1);
359 max
= int_const_binop (MINUS_EXPR
, min
, one
);
360 min
= vrp_val_min (TREE_TYPE (min
));
365 /* Do not drop [-INF(OVF), +INF(OVF)] to varying. (OVF) has to be sticky
366 to make sure VRP iteration terminates, otherwise we can get into
369 set_value_range (vr
, t
, min
, max
, equiv
);
372 /* Copy value range FROM into value range TO. */
375 copy_value_range (value_range
*to
, value_range
*from
)
377 set_value_range (to
, from
->type
, from
->min
, from
->max
, from
->equiv
);
380 /* Set value range VR to a single value. This function is only called
381 with values we get from statements, and exists to clear the
382 TREE_OVERFLOW flag. */
385 set_value_range_to_value (value_range
*vr
, tree val
, bitmap equiv
)
387 gcc_assert (is_gimple_min_invariant (val
));
388 if (TREE_OVERFLOW_P (val
))
389 val
= drop_tree_overflow (val
);
390 set_value_range (vr
, VR_RANGE
, val
, val
, equiv
);
393 /* Set value range VR to a non-negative range of type TYPE. */
396 set_value_range_to_nonnegative (value_range
*vr
, tree type
)
398 tree zero
= build_int_cst (type
, 0);
399 set_value_range (vr
, VR_RANGE
, zero
, vrp_val_max (type
), vr
->equiv
);
402 /* Set value range VR to a non-NULL range of type TYPE. */
405 set_value_range_to_nonnull (value_range
*vr
, tree type
)
407 tree zero
= build_int_cst (type
, 0);
408 set_value_range (vr
, VR_ANTI_RANGE
, zero
, zero
, vr
->equiv
);
412 /* Set value range VR to a NULL range of type TYPE. */
415 set_value_range_to_null (value_range
*vr
, tree type
)
417 set_value_range_to_value (vr
, build_int_cst (type
, 0), vr
->equiv
);
421 /* Set value range VR to a range of a truthvalue of type TYPE. */
424 set_value_range_to_truthvalue (value_range
*vr
, tree type
)
426 if (TYPE_PRECISION (type
) == 1)
427 set_value_range_to_varying (vr
);
429 set_value_range (vr
, VR_RANGE
,
430 build_int_cst (type
, 0), build_int_cst (type
, 1),
435 /* If abs (min) < abs (max), set VR to [-max, max], if
436 abs (min) >= abs (max), set VR to [-min, min]. */
439 abs_extent_range (value_range
*vr
, tree min
, tree max
)
443 gcc_assert (TREE_CODE (min
) == INTEGER_CST
);
444 gcc_assert (TREE_CODE (max
) == INTEGER_CST
);
445 gcc_assert (INTEGRAL_TYPE_P (TREE_TYPE (min
)));
446 gcc_assert (!TYPE_UNSIGNED (TREE_TYPE (min
)));
447 min
= fold_unary (ABS_EXPR
, TREE_TYPE (min
), min
);
448 max
= fold_unary (ABS_EXPR
, TREE_TYPE (max
), max
);
449 if (TREE_OVERFLOW (min
) || TREE_OVERFLOW (max
))
451 set_value_range_to_varying (vr
);
454 cmp
= compare_values (min
, max
);
456 min
= fold_unary (NEGATE_EXPR
, TREE_TYPE (min
), max
);
457 else if (cmp
== 0 || cmp
== 1)
460 min
= fold_unary (NEGATE_EXPR
, TREE_TYPE (min
), min
);
464 set_value_range_to_varying (vr
);
467 set_and_canonicalize_value_range (vr
, VR_RANGE
, min
, max
, NULL
);
471 /* Return value range information for VAR.
473 If we have no values ranges recorded (ie, VRP is not running), then
474 return NULL. Otherwise create an empty range if none existed for VAR. */
477 vr_values::get_value_range (const_tree var
)
479 static const value_range vr_const_varying
480 = { VR_VARYING
, NULL_TREE
, NULL_TREE
, NULL
};
483 unsigned ver
= SSA_NAME_VERSION (var
);
485 /* If we have no recorded ranges, then return NULL. */
489 /* If we query the range for a new SSA name return an unmodifiable VARYING.
490 We should get here at most from the substitute-and-fold stage which
491 will never try to change values. */
492 if (ver
>= num_vr_values
)
493 return CONST_CAST (value_range
*, &vr_const_varying
);
499 /* After propagation finished do not allocate new value-ranges. */
500 if (values_propagated
)
501 return CONST_CAST (value_range
*, &vr_const_varying
);
503 /* Create a default value range. */
504 vr_value
[ver
] = vr
= vrp_value_range_pool
.allocate ();
505 memset (vr
, 0, sizeof (*vr
));
507 /* Defer allocating the equivalence set. */
510 /* If VAR is a default definition of a parameter, the variable can
511 take any value in VAR's type. */
512 if (SSA_NAME_IS_DEFAULT_DEF (var
))
514 sym
= SSA_NAME_VAR (var
);
515 if (TREE_CODE (sym
) == PARM_DECL
)
517 /* Try to use the "nonnull" attribute to create ~[0, 0]
518 anti-ranges for pointers. Note that this is only valid with
519 default definitions of PARM_DECLs. */
520 if (POINTER_TYPE_P (TREE_TYPE (sym
))
521 && (nonnull_arg_p (sym
)
522 || get_ptr_nonnull (var
)))
523 set_value_range_to_nonnull (vr
, TREE_TYPE (sym
));
524 else if (INTEGRAL_TYPE_P (TREE_TYPE (sym
)))
527 value_range_type rtype
= get_range_info (var
, &min
, &max
);
528 if (rtype
== VR_RANGE
|| rtype
== VR_ANTI_RANGE
)
529 set_value_range (vr
, rtype
,
530 wide_int_to_tree (TREE_TYPE (var
), min
),
531 wide_int_to_tree (TREE_TYPE (var
), max
),
534 set_value_range_to_varying (vr
);
537 set_value_range_to_varying (vr
);
539 else if (TREE_CODE (sym
) == RESULT_DECL
540 && DECL_BY_REFERENCE (sym
))
541 set_value_range_to_nonnull (vr
, TREE_TYPE (sym
));
547 /* Set value-ranges of all SSA names defined by STMT to varying. */
550 vr_values::set_defs_to_varying (gimple
*stmt
)
554 FOR_EACH_SSA_TREE_OPERAND (def
, stmt
, i
, SSA_OP_DEF
)
556 value_range
*vr
= get_value_range (def
);
557 /* Avoid writing to vr_const_varying get_value_range may return. */
558 if (vr
->type
!= VR_VARYING
)
559 set_value_range_to_varying (vr
);
564 /* Return true, if VAL1 and VAL2 are equal values for VRP purposes. */
567 vrp_operand_equal_p (const_tree val1
, const_tree val2
)
571 if (!val1
|| !val2
|| !operand_equal_p (val1
, val2
, 0))
576 /* Return true, if the bitmaps B1 and B2 are equal. */
579 vrp_bitmap_equal_p (const_bitmap b1
, const_bitmap b2
)
582 || ((!b1
|| bitmap_empty_p (b1
))
583 && (!b2
|| bitmap_empty_p (b2
)))
585 && bitmap_equal_p (b1
, b2
)));
588 /* Update the value range and equivalence set for variable VAR to
589 NEW_VR. Return true if NEW_VR is different from VAR's previous
592 NOTE: This function assumes that NEW_VR is a temporary value range
593 object created for the sole purpose of updating VAR's range. The
594 storage used by the equivalence set from NEW_VR will be freed by
595 this function. Do not call update_value_range when NEW_VR
596 is the range object associated with another SSA name. */
599 vr_values::update_value_range (const_tree var
, value_range
*new_vr
)
604 /* If there is a value-range on the SSA name from earlier analysis
606 if (INTEGRAL_TYPE_P (TREE_TYPE (var
)))
609 value_range_type rtype
= get_range_info (var
, &min
, &max
);
610 if (rtype
== VR_RANGE
|| rtype
== VR_ANTI_RANGE
)
613 nr_min
= wide_int_to_tree (TREE_TYPE (var
), min
);
614 nr_max
= wide_int_to_tree (TREE_TYPE (var
), max
);
615 value_range nr
= VR_INITIALIZER
;
616 set_and_canonicalize_value_range (&nr
, rtype
, nr_min
, nr_max
, NULL
);
617 vrp_intersect_ranges (new_vr
, &nr
);
621 /* Update the value range, if necessary. */
622 old_vr
= get_value_range (var
);
623 is_new
= old_vr
->type
!= new_vr
->type
624 || !vrp_operand_equal_p (old_vr
->min
, new_vr
->min
)
625 || !vrp_operand_equal_p (old_vr
->max
, new_vr
->max
)
626 || !vrp_bitmap_equal_p (old_vr
->equiv
, new_vr
->equiv
);
630 /* Do not allow transitions up the lattice. The following
631 is slightly more awkward than just new_vr->type < old_vr->type
632 because VR_RANGE and VR_ANTI_RANGE need to be considered
633 the same. We may not have is_new when transitioning to
634 UNDEFINED. If old_vr->type is VARYING, we shouldn't be
636 if (new_vr
->type
== VR_UNDEFINED
)
638 BITMAP_FREE (new_vr
->equiv
);
639 set_value_range_to_varying (old_vr
);
640 set_value_range_to_varying (new_vr
);
644 set_value_range (old_vr
, new_vr
->type
, new_vr
->min
, new_vr
->max
,
648 BITMAP_FREE (new_vr
->equiv
);
654 /* Add VAR and VAR's equivalence set to EQUIV. This is the central
655 point where equivalence processing can be turned on/off. */
658 vr_values::add_equivalence (bitmap
*equiv
, const_tree var
)
660 unsigned ver
= SSA_NAME_VERSION (var
);
661 value_range
*vr
= get_value_range (var
);
664 *equiv
= BITMAP_ALLOC (&vrp_equiv_obstack
);
665 bitmap_set_bit (*equiv
, ver
);
667 bitmap_ior_into (*equiv
, vr
->equiv
);
671 /* Return true if VR is ~[0, 0]. */
674 range_is_nonnull (value_range
*vr
)
676 return vr
->type
== VR_ANTI_RANGE
677 && integer_zerop (vr
->min
)
678 && integer_zerop (vr
->max
);
682 /* Return true if VR is [0, 0]. */
685 range_is_null (value_range
*vr
)
687 return vr
->type
== VR_RANGE
688 && integer_zerop (vr
->min
)
689 && integer_zerop (vr
->max
);
692 /* Return true if max and min of VR are INTEGER_CST. It's not necessary
696 range_int_cst_p (value_range
*vr
)
698 return (vr
->type
== VR_RANGE
699 && TREE_CODE (vr
->max
) == INTEGER_CST
700 && TREE_CODE (vr
->min
) == INTEGER_CST
);
703 /* Return true if VR is a INTEGER_CST singleton. */
706 range_int_cst_singleton_p (value_range
*vr
)
708 return (range_int_cst_p (vr
)
709 && tree_int_cst_equal (vr
->min
, vr
->max
));
712 /* Return true if value range VR involves at least one symbol. */
715 symbolic_range_p (value_range
*vr
)
717 return (!is_gimple_min_invariant (vr
->min
)
718 || !is_gimple_min_invariant (vr
->max
));
721 /* Return the single symbol (an SSA_NAME) contained in T if any, or NULL_TREE
722 otherwise. We only handle additive operations and set NEG to true if the
723 symbol is negated and INV to the invariant part, if any. */
726 get_single_symbol (tree t
, bool *neg
, tree
*inv
)
734 if (TREE_CODE (t
) == PLUS_EXPR
735 || TREE_CODE (t
) == POINTER_PLUS_EXPR
736 || TREE_CODE (t
) == MINUS_EXPR
)
738 if (is_gimple_min_invariant (TREE_OPERAND (t
, 0)))
740 neg_
= (TREE_CODE (t
) == MINUS_EXPR
);
741 inv_
= TREE_OPERAND (t
, 0);
742 t
= TREE_OPERAND (t
, 1);
744 else if (is_gimple_min_invariant (TREE_OPERAND (t
, 1)))
747 inv_
= TREE_OPERAND (t
, 1);
748 t
= TREE_OPERAND (t
, 0);
759 if (TREE_CODE (t
) == NEGATE_EXPR
)
761 t
= TREE_OPERAND (t
, 0);
765 if (TREE_CODE (t
) != SSA_NAME
)
768 if (inv_
&& TREE_OVERFLOW_P (inv_
))
769 inv_
= drop_tree_overflow (inv_
);
776 /* The reverse operation: build a symbolic expression with TYPE
777 from symbol SYM, negated according to NEG, and invariant INV. */
780 build_symbolic_expr (tree type
, tree sym
, bool neg
, tree inv
)
782 const bool pointer_p
= POINTER_TYPE_P (type
);
786 t
= build1 (NEGATE_EXPR
, type
, t
);
788 if (integer_zerop (inv
))
791 return build2 (pointer_p
? POINTER_PLUS_EXPR
: PLUS_EXPR
, type
, t
, inv
);
794 /* Return true if value range VR involves exactly one symbol SYM. */
797 symbolic_range_based_on_p (value_range
*vr
, const_tree sym
)
799 bool neg
, min_has_symbol
, max_has_symbol
;
802 if (is_gimple_min_invariant (vr
->min
))
803 min_has_symbol
= false;
804 else if (get_single_symbol (vr
->min
, &neg
, &inv
) == sym
)
805 min_has_symbol
= true;
809 if (is_gimple_min_invariant (vr
->max
))
810 max_has_symbol
= false;
811 else if (get_single_symbol (vr
->max
, &neg
, &inv
) == sym
)
812 max_has_symbol
= true;
816 return (min_has_symbol
|| max_has_symbol
);
819 /* Return true if the result of assignment STMT is know to be non-zero. */
822 gimple_assign_nonzero_p (gimple
*stmt
)
824 enum tree_code code
= gimple_assign_rhs_code (stmt
);
825 bool strict_overflow_p
;
826 switch (get_gimple_rhs_class (code
))
828 case GIMPLE_UNARY_RHS
:
829 return tree_unary_nonzero_warnv_p (gimple_assign_rhs_code (stmt
),
830 gimple_expr_type (stmt
),
831 gimple_assign_rhs1 (stmt
),
833 case GIMPLE_BINARY_RHS
:
834 return tree_binary_nonzero_warnv_p (gimple_assign_rhs_code (stmt
),
835 gimple_expr_type (stmt
),
836 gimple_assign_rhs1 (stmt
),
837 gimple_assign_rhs2 (stmt
),
839 case GIMPLE_TERNARY_RHS
:
841 case GIMPLE_SINGLE_RHS
:
842 return tree_single_nonzero_warnv_p (gimple_assign_rhs1 (stmt
),
844 case GIMPLE_INVALID_RHS
:
851 /* Return true if STMT is known to compute a non-zero value. */
854 gimple_stmt_nonzero_p (gimple
*stmt
)
856 switch (gimple_code (stmt
))
859 return gimple_assign_nonzero_p (stmt
);
862 tree fndecl
= gimple_call_fndecl (stmt
);
863 if (!fndecl
) return false;
864 if (flag_delete_null_pointer_checks
&& !flag_check_new
865 && DECL_IS_OPERATOR_NEW (fndecl
)
866 && !TREE_NOTHROW (fndecl
))
868 /* References are always non-NULL. */
869 if (flag_delete_null_pointer_checks
870 && TREE_CODE (TREE_TYPE (fndecl
)) == REFERENCE_TYPE
)
872 if (flag_delete_null_pointer_checks
&&
873 lookup_attribute ("returns_nonnull",
874 TYPE_ATTRIBUTES (gimple_call_fntype (stmt
))))
877 gcall
*call_stmt
= as_a
<gcall
*> (stmt
);
878 unsigned rf
= gimple_call_return_flags (call_stmt
);
879 if (rf
& ERF_RETURNS_ARG
)
881 unsigned argnum
= rf
& ERF_RETURN_ARG_MASK
;
882 if (argnum
< gimple_call_num_args (call_stmt
))
884 tree arg
= gimple_call_arg (call_stmt
, argnum
);
886 && infer_nonnull_range_by_attribute (stmt
, arg
))
890 return gimple_alloca_call_p (stmt
);
897 /* Like tree_expr_nonzero_p, but this function uses value ranges
901 vr_values::vrp_stmt_computes_nonzero (gimple
*stmt
)
903 if (gimple_stmt_nonzero_p (stmt
))
906 /* If we have an expression of the form &X->a, then the expression
907 is nonnull if X is nonnull. */
908 if (is_gimple_assign (stmt
)
909 && gimple_assign_rhs_code (stmt
) == ADDR_EXPR
)
911 tree expr
= gimple_assign_rhs1 (stmt
);
912 tree base
= get_base_address (TREE_OPERAND (expr
, 0));
914 if (base
!= NULL_TREE
915 && TREE_CODE (base
) == MEM_REF
916 && TREE_CODE (TREE_OPERAND (base
, 0)) == SSA_NAME
)
918 value_range
*vr
= get_value_range (TREE_OPERAND (base
, 0));
919 if (range_is_nonnull (vr
))
927 /* Returns true if EXPR is a valid value (as expected by compare_values) --
928 a gimple invariant, or SSA_NAME +- CST. */
931 valid_value_p (tree expr
)
933 if (TREE_CODE (expr
) == SSA_NAME
)
936 if (TREE_CODE (expr
) == PLUS_EXPR
937 || TREE_CODE (expr
) == MINUS_EXPR
)
938 return (TREE_CODE (TREE_OPERAND (expr
, 0)) == SSA_NAME
939 && TREE_CODE (TREE_OPERAND (expr
, 1)) == INTEGER_CST
);
941 return is_gimple_min_invariant (expr
);
947 -2 if those are incomparable. */
949 operand_less_p (tree val
, tree val2
)
951 /* LT is folded faster than GE and others. Inline the common case. */
952 if (TREE_CODE (val
) == INTEGER_CST
&& TREE_CODE (val2
) == INTEGER_CST
)
953 return tree_int_cst_lt (val
, val2
);
958 fold_defer_overflow_warnings ();
960 tcmp
= fold_binary_to_constant (LT_EXPR
, boolean_type_node
, val
, val2
);
962 fold_undefer_and_ignore_overflow_warnings ();
965 || TREE_CODE (tcmp
) != INTEGER_CST
)
968 if (!integer_zerop (tcmp
))
975 /* Compare two values VAL1 and VAL2. Return
977 -2 if VAL1 and VAL2 cannot be compared at compile-time,
980 +1 if VAL1 > VAL2, and
983 This is similar to tree_int_cst_compare but supports pointer values
984 and values that cannot be compared at compile time.
986 If STRICT_OVERFLOW_P is not NULL, then set *STRICT_OVERFLOW_P to
987 true if the return value is only valid if we assume that signed
988 overflow is undefined. */
991 compare_values_warnv (tree val1
, tree val2
, bool *strict_overflow_p
)
996 /* Below we rely on the fact that VAL1 and VAL2 are both pointers or
998 gcc_assert (POINTER_TYPE_P (TREE_TYPE (val1
))
999 == POINTER_TYPE_P (TREE_TYPE (val2
)));
1001 /* Convert the two values into the same type. This is needed because
1002 sizetype causes sign extension even for unsigned types. */
1003 val2
= fold_convert (TREE_TYPE (val1
), val2
);
1004 STRIP_USELESS_TYPE_CONVERSION (val2
);
1006 const bool overflow_undefined
1007 = INTEGRAL_TYPE_P (TREE_TYPE (val1
))
1008 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (val1
));
1011 tree sym1
= get_single_symbol (val1
, &neg1
, &inv1
);
1012 tree sym2
= get_single_symbol (val2
, &neg2
, &inv2
);
1014 /* If VAL1 and VAL2 are of the form '[-]NAME [+ CST]', return -1 or +1
1015 accordingly. If VAL1 and VAL2 don't use the same name, return -2. */
1018 /* Both values must use the same name with the same sign. */
1019 if (sym1
!= sym2
|| neg1
!= neg2
)
1022 /* [-]NAME + CST == [-]NAME + CST. */
1026 /* If overflow is defined we cannot simplify more. */
1027 if (!overflow_undefined
)
1030 if (strict_overflow_p
!= NULL
1031 /* Symbolic range building sets TREE_NO_WARNING to declare
1032 that overflow doesn't happen. */
1033 && (!inv1
|| !TREE_NO_WARNING (val1
))
1034 && (!inv2
|| !TREE_NO_WARNING (val2
)))
1035 *strict_overflow_p
= true;
1038 inv1
= build_int_cst (TREE_TYPE (val1
), 0);
1040 inv2
= build_int_cst (TREE_TYPE (val2
), 0);
1042 return wi::cmp (wi::to_wide (inv1
), wi::to_wide (inv2
),
1043 TYPE_SIGN (TREE_TYPE (val1
)));
1046 const bool cst1
= is_gimple_min_invariant (val1
);
1047 const bool cst2
= is_gimple_min_invariant (val2
);
1049 /* If one is of the form '[-]NAME + CST' and the other is constant, then
1050 it might be possible to say something depending on the constants. */
1051 if ((sym1
&& inv1
&& cst2
) || (sym2
&& inv2
&& cst1
))
1053 if (!overflow_undefined
)
1056 if (strict_overflow_p
!= NULL
1057 /* Symbolic range building sets TREE_NO_WARNING to declare
1058 that overflow doesn't happen. */
1059 && (!sym1
|| !TREE_NO_WARNING (val1
))
1060 && (!sym2
|| !TREE_NO_WARNING (val2
)))
1061 *strict_overflow_p
= true;
1063 const signop sgn
= TYPE_SIGN (TREE_TYPE (val1
));
1064 tree cst
= cst1
? val1
: val2
;
1065 tree inv
= cst1
? inv2
: inv1
;
1067 /* Compute the difference between the constants. If it overflows or
1068 underflows, this means that we can trivially compare the NAME with
1069 it and, consequently, the two values with each other. */
1070 wide_int diff
= wi::to_wide (cst
) - wi::to_wide (inv
);
1071 if (wi::cmp (0, wi::to_wide (inv
), sgn
)
1072 != wi::cmp (diff
, wi::to_wide (cst
), sgn
))
1074 const int res
= wi::cmp (wi::to_wide (cst
), wi::to_wide (inv
), sgn
);
1075 return cst1
? res
: -res
;
1081 /* We cannot say anything more for non-constants. */
1085 if (!POINTER_TYPE_P (TREE_TYPE (val1
)))
1087 /* We cannot compare overflowed values. */
1088 if (TREE_OVERFLOW (val1
) || TREE_OVERFLOW (val2
))
1091 return tree_int_cst_compare (val1
, val2
);
1097 /* First see if VAL1 and VAL2 are not the same. */
1098 if (val1
== val2
|| operand_equal_p (val1
, val2
, 0))
1101 /* If VAL1 is a lower address than VAL2, return -1. */
1102 if (operand_less_p (val1
, val2
) == 1)
1105 /* If VAL1 is a higher address than VAL2, return +1. */
1106 if (operand_less_p (val2
, val1
) == 1)
1109 /* If VAL1 is different than VAL2, return +2.
1110 For integer constants we either have already returned -1 or 1
1111 or they are equivalent. We still might succeed in proving
1112 something about non-trivial operands. */
1113 if (TREE_CODE (val1
) != INTEGER_CST
1114 || TREE_CODE (val2
) != INTEGER_CST
)
1116 t
= fold_binary_to_constant (NE_EXPR
, boolean_type_node
, val1
, val2
);
1117 if (t
&& integer_onep (t
))
1125 /* Compare values like compare_values_warnv. */
1128 compare_values (tree val1
, tree val2
)
1131 return compare_values_warnv (val1
, val2
, &sop
);
1135 /* Return 1 if VAL is inside value range MIN <= VAL <= MAX,
1136 0 if VAL is not inside [MIN, MAX],
1137 -2 if we cannot tell either way.
1139 Benchmark compile/20001226-1.c compilation time after changing this
1143 value_inside_range (tree val
, tree min
, tree max
)
1147 cmp1
= operand_less_p (val
, min
);
1153 cmp2
= operand_less_p (max
, val
);
1161 /* Return true if value ranges VR0 and VR1 have a non-empty
1164 Benchmark compile/20001226-1.c compilation time after changing this
1169 value_ranges_intersect_p (value_range
*vr0
, value_range
*vr1
)
1171 /* The value ranges do not intersect if the maximum of the first range is
1172 less than the minimum of the second range or vice versa.
1173 When those relations are unknown, we can't do any better. */
1174 if (operand_less_p (vr0
->max
, vr1
->min
) != 0)
1176 if (operand_less_p (vr1
->max
, vr0
->min
) != 0)
1182 /* Return 1 if [MIN, MAX] includes the value zero, 0 if it does not
1183 include the value zero, -2 if we cannot tell. */
1186 range_includes_zero_p (tree min
, tree max
)
1188 tree zero
= build_int_cst (TREE_TYPE (min
), 0);
1189 return value_inside_range (zero
, min
, max
);
1192 /* Return true if *VR is know to only contain nonnegative values. */
1195 value_range_nonnegative_p (value_range
*vr
)
1197 /* Testing for VR_ANTI_RANGE is not useful here as any anti-range
1198 which would return a useful value should be encoded as a
1200 if (vr
->type
== VR_RANGE
)
1202 int result
= compare_values (vr
->min
, integer_zero_node
);
1203 return (result
== 0 || result
== 1);
1209 /* If *VR has a value rante that is a single constant value return that,
1210 otherwise return NULL_TREE. */
1213 value_range_constant_singleton (value_range
*vr
)
1215 if (vr
->type
== VR_RANGE
1216 && vrp_operand_equal_p (vr
->min
, vr
->max
)
1217 && is_gimple_min_invariant (vr
->min
))
1223 /* If OP has a value range with a single constant value return that,
1224 otherwise return NULL_TREE. This returns OP itself if OP is a
1228 vr_values::op_with_constant_singleton_value_range (tree op
)
1230 if (is_gimple_min_invariant (op
))
1233 if (TREE_CODE (op
) != SSA_NAME
)
1236 return value_range_constant_singleton (get_value_range (op
));
1239 /* Return true if op is in a boolean [0, 1] value-range. */
1242 vr_values::op_with_boolean_value_range_p (tree op
)
1246 if (TYPE_PRECISION (TREE_TYPE (op
)) == 1)
1249 if (integer_zerop (op
)
1250 || integer_onep (op
))
1253 if (TREE_CODE (op
) != SSA_NAME
)
1256 vr
= get_value_range (op
);
1257 return (vr
->type
== VR_RANGE
1258 && integer_zerop (vr
->min
)
1259 && integer_onep (vr
->max
));
1262 /* Extract value range information for VAR when (OP COND_CODE LIMIT) is
1263 true and store it in *VR_P. */
1266 vr_values::extract_range_for_var_from_comparison_expr (tree var
,
1267 enum tree_code cond_code
,
1268 tree op
, tree limit
,
1271 tree min
, max
, type
;
1272 value_range
*limit_vr
;
1273 type
= TREE_TYPE (var
);
1274 gcc_assert (limit
!= var
);
1276 /* For pointer arithmetic, we only keep track of pointer equality
1278 if (POINTER_TYPE_P (type
) && cond_code
!= NE_EXPR
&& cond_code
!= EQ_EXPR
)
1280 set_value_range_to_varying (vr_p
);
1284 /* If LIMIT is another SSA name and LIMIT has a range of its own,
1285 try to use LIMIT's range to avoid creating symbolic ranges
1287 limit_vr
= (TREE_CODE (limit
) == SSA_NAME
) ? get_value_range (limit
) : NULL
;
1289 /* LIMIT's range is only interesting if it has any useful information. */
1291 || limit_vr
->type
== VR_UNDEFINED
1292 || limit_vr
->type
== VR_VARYING
1293 || (symbolic_range_p (limit_vr
)
1294 && ! (limit_vr
->type
== VR_RANGE
1295 && (limit_vr
->min
== limit_vr
->max
1296 || operand_equal_p (limit_vr
->min
, limit_vr
->max
, 0)))))
1299 /* Initially, the new range has the same set of equivalences of
1300 VAR's range. This will be revised before returning the final
1301 value. Since assertions may be chained via mutually exclusive
1302 predicates, we will need to trim the set of equivalences before
1304 gcc_assert (vr_p
->equiv
== NULL
);
1305 add_equivalence (&vr_p
->equiv
, var
);
1307 /* Extract a new range based on the asserted comparison for VAR and
1308 LIMIT's value range. Notice that if LIMIT has an anti-range, we
1309 will only use it for equality comparisons (EQ_EXPR). For any
1310 other kind of assertion, we cannot derive a range from LIMIT's
1311 anti-range that can be used to describe the new range. For
1312 instance, ASSERT_EXPR <x_2, x_2 <= b_4>. If b_4 is ~[2, 10],
1313 then b_4 takes on the ranges [-INF, 1] and [11, +INF]. There is
1314 no single range for x_2 that could describe LE_EXPR, so we might
1315 as well build the range [b_4, +INF] for it.
1316 One special case we handle is extracting a range from a
1317 range test encoded as (unsigned)var + CST <= limit. */
1318 if (TREE_CODE (op
) == NOP_EXPR
1319 || TREE_CODE (op
) == PLUS_EXPR
)
1321 if (TREE_CODE (op
) == PLUS_EXPR
)
1323 min
= fold_build1 (NEGATE_EXPR
, TREE_TYPE (TREE_OPERAND (op
, 1)),
1324 TREE_OPERAND (op
, 1));
1325 max
= int_const_binop (PLUS_EXPR
, limit
, min
);
1326 op
= TREE_OPERAND (op
, 0);
1330 min
= build_int_cst (TREE_TYPE (var
), 0);
1334 /* Make sure to not set TREE_OVERFLOW on the final type
1335 conversion. We are willingly interpreting large positive
1336 unsigned values as negative signed values here. */
1337 min
= force_fit_type (TREE_TYPE (var
), wi::to_widest (min
), 0, false);
1338 max
= force_fit_type (TREE_TYPE (var
), wi::to_widest (max
), 0, false);
1340 /* We can transform a max, min range to an anti-range or
1341 vice-versa. Use set_and_canonicalize_value_range which does
1343 if (cond_code
== LE_EXPR
)
1344 set_and_canonicalize_value_range (vr_p
, VR_RANGE
,
1345 min
, max
, vr_p
->equiv
);
1346 else if (cond_code
== GT_EXPR
)
1347 set_and_canonicalize_value_range (vr_p
, VR_ANTI_RANGE
,
1348 min
, max
, vr_p
->equiv
);
1352 else if (cond_code
== EQ_EXPR
)
1354 enum value_range_type range_type
;
1358 range_type
= limit_vr
->type
;
1359 min
= limit_vr
->min
;
1360 max
= limit_vr
->max
;
1364 range_type
= VR_RANGE
;
1369 set_value_range (vr_p
, range_type
, min
, max
, vr_p
->equiv
);
1371 /* When asserting the equality VAR == LIMIT and LIMIT is another
1372 SSA name, the new range will also inherit the equivalence set
1374 if (TREE_CODE (limit
) == SSA_NAME
)
1375 add_equivalence (&vr_p
->equiv
, limit
);
1377 else if (cond_code
== NE_EXPR
)
1379 /* As described above, when LIMIT's range is an anti-range and
1380 this assertion is an inequality (NE_EXPR), then we cannot
1381 derive anything from the anti-range. For instance, if
1382 LIMIT's range was ~[0, 0], the assertion 'VAR != LIMIT' does
1383 not imply that VAR's range is [0, 0]. So, in the case of
1384 anti-ranges, we just assert the inequality using LIMIT and
1387 If LIMIT_VR is a range, we can only use it to build a new
1388 anti-range if LIMIT_VR is a single-valued range. For
1389 instance, if LIMIT_VR is [0, 1], the predicate
1390 VAR != [0, 1] does not mean that VAR's range is ~[0, 1].
1391 Rather, it means that for value 0 VAR should be ~[0, 0]
1392 and for value 1, VAR should be ~[1, 1]. We cannot
1393 represent these ranges.
1395 The only situation in which we can build a valid
1396 anti-range is when LIMIT_VR is a single-valued range
1397 (i.e., LIMIT_VR->MIN == LIMIT_VR->MAX). In that case,
1398 build the anti-range ~[LIMIT_VR->MIN, LIMIT_VR->MAX]. */
1400 && limit_vr
->type
== VR_RANGE
1401 && compare_values (limit_vr
->min
, limit_vr
->max
) == 0)
1403 min
= limit_vr
->min
;
1404 max
= limit_vr
->max
;
1408 /* In any other case, we cannot use LIMIT's range to build a
1409 valid anti-range. */
1413 /* If MIN and MAX cover the whole range for their type, then
1414 just use the original LIMIT. */
1415 if (INTEGRAL_TYPE_P (type
)
1416 && vrp_val_is_min (min
)
1417 && vrp_val_is_max (max
))
1420 set_and_canonicalize_value_range (vr_p
, VR_ANTI_RANGE
,
1421 min
, max
, vr_p
->equiv
);
1423 else if (cond_code
== LE_EXPR
|| cond_code
== LT_EXPR
)
1425 min
= TYPE_MIN_VALUE (type
);
1427 if (limit_vr
== NULL
|| limit_vr
->type
== VR_ANTI_RANGE
)
1431 /* If LIMIT_VR is of the form [N1, N2], we need to build the
1432 range [MIN, N2] for LE_EXPR and [MIN, N2 - 1] for
1434 max
= limit_vr
->max
;
1437 /* If the maximum value forces us to be out of bounds, simply punt.
1438 It would be pointless to try and do anything more since this
1439 all should be optimized away above us. */
1440 if (cond_code
== LT_EXPR
1441 && compare_values (max
, min
) == 0)
1442 set_value_range_to_varying (vr_p
);
1445 /* For LT_EXPR, we create the range [MIN, MAX - 1]. */
1446 if (cond_code
== LT_EXPR
)
1448 if (TYPE_PRECISION (TREE_TYPE (max
)) == 1
1449 && !TYPE_UNSIGNED (TREE_TYPE (max
)))
1450 max
= fold_build2 (PLUS_EXPR
, TREE_TYPE (max
), max
,
1451 build_int_cst (TREE_TYPE (max
), -1));
1453 max
= fold_build2 (MINUS_EXPR
, TREE_TYPE (max
), max
,
1454 build_int_cst (TREE_TYPE (max
), 1));
1455 /* Signal to compare_values_warnv this expr doesn't overflow. */
1457 TREE_NO_WARNING (max
) = 1;
1460 set_value_range (vr_p
, VR_RANGE
, min
, max
, vr_p
->equiv
);
1463 else if (cond_code
== GE_EXPR
|| cond_code
== GT_EXPR
)
1465 max
= TYPE_MAX_VALUE (type
);
1467 if (limit_vr
== NULL
|| limit_vr
->type
== VR_ANTI_RANGE
)
1471 /* If LIMIT_VR is of the form [N1, N2], we need to build the
1472 range [N1, MAX] for GE_EXPR and [N1 + 1, MAX] for
1474 min
= limit_vr
->min
;
1477 /* If the minimum value forces us to be out of bounds, simply punt.
1478 It would be pointless to try and do anything more since this
1479 all should be optimized away above us. */
1480 if (cond_code
== GT_EXPR
1481 && compare_values (min
, max
) == 0)
1482 set_value_range_to_varying (vr_p
);
1485 /* For GT_EXPR, we create the range [MIN + 1, MAX]. */
1486 if (cond_code
== GT_EXPR
)
1488 if (TYPE_PRECISION (TREE_TYPE (min
)) == 1
1489 && !TYPE_UNSIGNED (TREE_TYPE (min
)))
1490 min
= fold_build2 (MINUS_EXPR
, TREE_TYPE (min
), min
,
1491 build_int_cst (TREE_TYPE (min
), -1));
1493 min
= fold_build2 (PLUS_EXPR
, TREE_TYPE (min
), min
,
1494 build_int_cst (TREE_TYPE (min
), 1));
1495 /* Signal to compare_values_warnv this expr doesn't overflow. */
1497 TREE_NO_WARNING (min
) = 1;
1500 set_value_range (vr_p
, VR_RANGE
, min
, max
, vr_p
->equiv
);
1506 /* Finally intersect the new range with what we already know about var. */
1507 vrp_intersect_ranges (vr_p
, get_value_range (var
));
1510 /* Extract value range information from an ASSERT_EXPR EXPR and store
1514 vr_values::extract_range_from_assert (value_range
*vr_p
, tree expr
)
1516 tree var
= ASSERT_EXPR_VAR (expr
);
1517 tree cond
= ASSERT_EXPR_COND (expr
);
1519 enum tree_code cond_code
;
1520 gcc_assert (COMPARISON_CLASS_P (cond
));
1522 /* Find VAR in the ASSERT_EXPR conditional. */
1523 if (var
== TREE_OPERAND (cond
, 0)
1524 || TREE_CODE (TREE_OPERAND (cond
, 0)) == PLUS_EXPR
1525 || TREE_CODE (TREE_OPERAND (cond
, 0)) == NOP_EXPR
)
1527 /* If the predicate is of the form VAR COMP LIMIT, then we just
1528 take LIMIT from the RHS and use the same comparison code. */
1529 cond_code
= TREE_CODE (cond
);
1530 limit
= TREE_OPERAND (cond
, 1);
1531 op
= TREE_OPERAND (cond
, 0);
1535 /* If the predicate is of the form LIMIT COMP VAR, then we need
1536 to flip around the comparison code to create the proper range
1538 cond_code
= swap_tree_comparison (TREE_CODE (cond
));
1539 limit
= TREE_OPERAND (cond
, 0);
1540 op
= TREE_OPERAND (cond
, 1);
1542 extract_range_for_var_from_comparison_expr (var
, cond_code
, op
,
1546 /* Extract range information from SSA name VAR and store it in VR. If
1547 VAR has an interesting range, use it. Otherwise, create the
1548 range [VAR, VAR] and return it. This is useful in situations where
1549 we may have conditionals testing values of VARYING names. For
1556 Even if y_5 is deemed VARYING, we can determine that x_3 > y_5 is
1560 vr_values::extract_range_from_ssa_name (value_range
*vr
, tree var
)
1562 value_range
*var_vr
= get_value_range (var
);
1564 if (var_vr
->type
!= VR_VARYING
)
1565 copy_value_range (vr
, var_vr
);
1567 set_value_range (vr
, VR_RANGE
, var
, var
, NULL
);
1569 add_equivalence (&vr
->equiv
, var
);
1573 /* Wrapper around int_const_binop. Return true if we can compute the
1574 result; i.e. if the operation doesn't overflow or if the overflow is
1575 undefined. In the latter case (if the operation overflows and
1576 overflow is undefined), then adjust the result to be -INF or +INF
1577 depending on CODE, VAL1 and VAL2. Return the value in *RES.
1579 Return false for division by zero, for which the result is
1583 vrp_int_const_binop (enum tree_code code
, tree val1
, tree val2
, wide_int
*res
)
1585 bool overflow
= false;
1586 signop sign
= TYPE_SIGN (TREE_TYPE (val1
));
1593 wide_int wval2
= wi::to_wide (val2
, TYPE_PRECISION (TREE_TYPE (val1
)));
1594 if (wi::neg_p (wval2
))
1597 if (code
== RSHIFT_EXPR
)
1603 if (code
== RSHIFT_EXPR
)
1604 /* It's unclear from the C standard whether shifts can overflow.
1605 The following code ignores overflow; perhaps a C standard
1606 interpretation ruling is needed. */
1607 *res
= wi::rshift (wi::to_wide (val1
), wval2
, sign
);
1609 *res
= wi::lshift (wi::to_wide (val1
), wval2
);
1614 *res
= wi::mul (wi::to_wide (val1
),
1615 wi::to_wide (val2
), sign
, &overflow
);
1618 case TRUNC_DIV_EXPR
:
1619 case EXACT_DIV_EXPR
:
1623 *res
= wi::div_trunc (wi::to_wide (val1
),
1624 wi::to_wide (val2
), sign
, &overflow
);
1627 case FLOOR_DIV_EXPR
:
1630 *res
= wi::div_floor (wi::to_wide (val1
),
1631 wi::to_wide (val2
), sign
, &overflow
);
1637 *res
= wi::div_ceil (wi::to_wide (val1
),
1638 wi::to_wide (val2
), sign
, &overflow
);
1641 case ROUND_DIV_EXPR
:
1644 *res
= wi::div_round (wi::to_wide (val1
),
1645 wi::to_wide (val2
), sign
, &overflow
);
1653 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (val1
)))
1655 /* If the operation overflowed return -INF or +INF depending
1656 on the operation and the combination of signs of the operands. */
1657 int sgn1
= tree_int_cst_sgn (val1
);
1658 int sgn2
= tree_int_cst_sgn (val2
);
1660 /* Notice that we only need to handle the restricted set of
1661 operations handled by extract_range_from_binary_expr.
1662 Among them, only multiplication, addition and subtraction
1663 can yield overflow without overflown operands because we
1664 are working with integral types only... except in the
1665 case VAL1 = -INF and VAL2 = -1 which overflows to +INF
1666 for division too. */
1668 /* For multiplication, the sign of the overflow is given
1669 by the comparison of the signs of the operands. */
1670 if ((code
== MULT_EXPR
&& sgn1
== sgn2
)
1671 /* For addition, the operands must be of the same sign
1672 to yield an overflow. Its sign is therefore that
1673 of one of the operands, for example the first. */
1674 || (code
== PLUS_EXPR
&& sgn1
>= 0)
1675 /* For subtraction, operands must be of
1676 different signs to yield an overflow. Its sign is
1677 therefore that of the first operand or the opposite of
1678 that of the second operand. A first operand of 0 counts
1679 as positive here, for the corner case 0 - (-INF), which
1680 overflows, but must yield +INF. */
1681 || (code
== MINUS_EXPR
&& sgn1
>= 0)
1682 /* For division, the only case is -INF / -1 = +INF. */
1683 || code
== TRUNC_DIV_EXPR
1684 || code
== FLOOR_DIV_EXPR
1685 || code
== CEIL_DIV_EXPR
1686 || code
== EXACT_DIV_EXPR
1687 || code
== ROUND_DIV_EXPR
)
1688 *res
= wi::max_value (TYPE_PRECISION (TREE_TYPE (val1
)),
1689 TYPE_SIGN (TREE_TYPE (val1
)));
1691 *res
= wi::min_value (TYPE_PRECISION (TREE_TYPE (val1
)),
1692 TYPE_SIGN (TREE_TYPE (val1
)));
1700 /* For range VR compute two wide_int bitmasks. In *MAY_BE_NONZERO
1701 bitmask if some bit is unset, it means for all numbers in the range
1702 the bit is 0, otherwise it might be 0 or 1. In *MUST_BE_NONZERO
1703 bitmask if some bit is set, it means for all numbers in the range
1704 the bit is 1, otherwise it might be 0 or 1. */
1707 zero_nonzero_bits_from_vr (const tree expr_type
,
1709 wide_int
*may_be_nonzero
,
1710 wide_int
*must_be_nonzero
)
1712 *may_be_nonzero
= wi::minus_one (TYPE_PRECISION (expr_type
));
1713 *must_be_nonzero
= wi::zero (TYPE_PRECISION (expr_type
));
1714 if (!range_int_cst_p (vr
))
1717 if (range_int_cst_singleton_p (vr
))
1719 *may_be_nonzero
= wi::to_wide (vr
->min
);
1720 *must_be_nonzero
= *may_be_nonzero
;
1722 else if (tree_int_cst_sgn (vr
->min
) >= 0
1723 || tree_int_cst_sgn (vr
->max
) < 0)
1725 wide_int xor_mask
= wi::to_wide (vr
->min
) ^ wi::to_wide (vr
->max
);
1726 *may_be_nonzero
= wi::to_wide (vr
->min
) | wi::to_wide (vr
->max
);
1727 *must_be_nonzero
= wi::to_wide (vr
->min
) & wi::to_wide (vr
->max
);
1730 wide_int mask
= wi::mask (wi::floor_log2 (xor_mask
), false,
1731 may_be_nonzero
->get_precision ());
1732 *may_be_nonzero
= *may_be_nonzero
| mask
;
1733 *must_be_nonzero
= wi::bit_and_not (*must_be_nonzero
, mask
);
1740 /* Create two value-ranges in *VR0 and *VR1 from the anti-range *AR
1741 so that *VR0 U *VR1 == *AR. Returns true if that is possible,
1742 false otherwise. If *AR can be represented with a single range
1743 *VR1 will be VR_UNDEFINED. */
1746 ranges_from_anti_range (value_range
*ar
,
1747 value_range
*vr0
, value_range
*vr1
)
1749 tree type
= TREE_TYPE (ar
->min
);
1751 vr0
->type
= VR_UNDEFINED
;
1752 vr1
->type
= VR_UNDEFINED
;
1754 if (ar
->type
!= VR_ANTI_RANGE
1755 || TREE_CODE (ar
->min
) != INTEGER_CST
1756 || TREE_CODE (ar
->max
) != INTEGER_CST
1757 || !vrp_val_min (type
)
1758 || !vrp_val_max (type
))
1761 if (!vrp_val_is_min (ar
->min
))
1763 vr0
->type
= VR_RANGE
;
1764 vr0
->min
= vrp_val_min (type
);
1765 vr0
->max
= wide_int_to_tree (type
, wi::to_wide (ar
->min
) - 1);
1767 if (!vrp_val_is_max (ar
->max
))
1769 vr1
->type
= VR_RANGE
;
1770 vr1
->min
= wide_int_to_tree (type
, wi::to_wide (ar
->max
) + 1);
1771 vr1
->max
= vrp_val_max (type
);
1773 if (vr0
->type
== VR_UNDEFINED
)
1776 vr1
->type
= VR_UNDEFINED
;
1779 return vr0
->type
!= VR_UNDEFINED
;
1782 /* Helper to extract a value-range *VR for a multiplicative operation
1786 extract_range_from_multiplicative_op_1 (value_range
*vr
,
1787 enum tree_code code
,
1788 value_range
*vr0
, value_range
*vr1
)
1790 enum value_range_type rtype
;
1791 wide_int val
, min
, max
;
1794 /* Multiplications, divisions and shifts are a bit tricky to handle,
1795 depending on the mix of signs we have in the two ranges, we
1796 need to operate on different values to get the minimum and
1797 maximum values for the new range. One approach is to figure
1798 out all the variations of range combinations and do the
1801 However, this involves several calls to compare_values and it
1802 is pretty convoluted. It's simpler to do the 4 operations
1803 (MIN0 OP MIN1, MIN0 OP MAX1, MAX0 OP MIN1 and MAX0 OP MAX0 OP
1804 MAX1) and then figure the smallest and largest values to form
1806 gcc_assert (code
== MULT_EXPR
1807 || code
== TRUNC_DIV_EXPR
1808 || code
== FLOOR_DIV_EXPR
1809 || code
== CEIL_DIV_EXPR
1810 || code
== EXACT_DIV_EXPR
1811 || code
== ROUND_DIV_EXPR
1812 || code
== RSHIFT_EXPR
1813 || code
== LSHIFT_EXPR
);
1814 gcc_assert (vr0
->type
== VR_RANGE
1815 && vr0
->type
== vr1
->type
);
1818 type
= TREE_TYPE (vr0
->min
);
1819 signop sgn
= TYPE_SIGN (type
);
1821 /* Compute the 4 cross operations and their minimum and maximum value. */
1822 if (!vrp_int_const_binop (code
, vr0
->min
, vr1
->min
, &val
))
1824 set_value_range_to_varying (vr
);
1829 if (vr1
->max
!= vr1
->min
)
1831 if (!vrp_int_const_binop (code
, vr0
->min
, vr1
->max
, &val
))
1833 set_value_range_to_varying (vr
);
1836 if (wi::lt_p (val
, min
, sgn
))
1838 else if (wi::gt_p (val
, max
, sgn
))
1842 if (vr0
->max
!= vr0
->min
)
1844 if (!vrp_int_const_binop (code
, vr0
->max
, vr1
->min
, &val
))
1846 set_value_range_to_varying (vr
);
1849 if (wi::lt_p (val
, min
, sgn
))
1851 else if (wi::gt_p (val
, max
, sgn
))
1855 if (vr0
->min
!= vr0
->max
&& vr1
->min
!= vr1
->max
)
1857 if (!vrp_int_const_binop (code
, vr0
->max
, vr1
->max
, &val
))
1859 set_value_range_to_varying (vr
);
1862 if (wi::lt_p (val
, min
, sgn
))
1864 else if (wi::gt_p (val
, max
, sgn
))
1868 /* If the new range has its limits swapped around (MIN > MAX),
1869 then the operation caused one of them to wrap around, mark
1870 the new range VARYING. */
1871 if (wi::gt_p (min
, max
, sgn
))
1873 set_value_range_to_varying (vr
);
1877 /* We punt for [-INF, +INF].
1878 We learn nothing when we have INF on both sides.
1879 Note that we do accept [-INF, -INF] and [+INF, +INF]. */
1880 if (wi::eq_p (min
, wi::min_value (TYPE_PRECISION (type
), sgn
))
1881 && wi::eq_p (max
, wi::max_value (TYPE_PRECISION (type
), sgn
)))
1883 set_value_range_to_varying (vr
);
1887 set_value_range (vr
, rtype
,
1888 wide_int_to_tree (type
, min
),
1889 wide_int_to_tree (type
, max
), NULL
);
1892 /* Extract range information from a binary operation CODE based on
1893 the ranges of each of its operands *VR0 and *VR1 with resulting
1894 type EXPR_TYPE. The resulting range is stored in *VR. */
1897 extract_range_from_binary_expr_1 (value_range
*vr
,
1898 enum tree_code code
, tree expr_type
,
1899 value_range
*vr0_
, value_range
*vr1_
)
1901 value_range vr0
= *vr0_
, vr1
= *vr1_
;
1902 value_range vrtem0
= VR_INITIALIZER
, vrtem1
= VR_INITIALIZER
;
1903 enum value_range_type type
;
1904 tree min
= NULL_TREE
, max
= NULL_TREE
;
1907 if (!INTEGRAL_TYPE_P (expr_type
)
1908 && !POINTER_TYPE_P (expr_type
))
1910 set_value_range_to_varying (vr
);
1914 /* Not all binary expressions can be applied to ranges in a
1915 meaningful way. Handle only arithmetic operations. */
1916 if (code
!= PLUS_EXPR
1917 && code
!= MINUS_EXPR
1918 && code
!= POINTER_PLUS_EXPR
1919 && code
!= MULT_EXPR
1920 && code
!= TRUNC_DIV_EXPR
1921 && code
!= FLOOR_DIV_EXPR
1922 && code
!= CEIL_DIV_EXPR
1923 && code
!= EXACT_DIV_EXPR
1924 && code
!= ROUND_DIV_EXPR
1925 && code
!= TRUNC_MOD_EXPR
1926 && code
!= RSHIFT_EXPR
1927 && code
!= LSHIFT_EXPR
1930 && code
!= BIT_AND_EXPR
1931 && code
!= BIT_IOR_EXPR
1932 && code
!= BIT_XOR_EXPR
)
1934 set_value_range_to_varying (vr
);
1938 /* If both ranges are UNDEFINED, so is the result. */
1939 if (vr0
.type
== VR_UNDEFINED
&& vr1
.type
== VR_UNDEFINED
)
1941 set_value_range_to_undefined (vr
);
1944 /* If one of the ranges is UNDEFINED drop it to VARYING for the following
1945 code. At some point we may want to special-case operations that
1946 have UNDEFINED result for all or some value-ranges of the not UNDEFINED
1948 else if (vr0
.type
== VR_UNDEFINED
)
1949 set_value_range_to_varying (&vr0
);
1950 else if (vr1
.type
== VR_UNDEFINED
)
1951 set_value_range_to_varying (&vr1
);
1953 /* We get imprecise results from ranges_from_anti_range when
1954 code is EXACT_DIV_EXPR. We could mask out bits in the resulting
1955 range, but then we also need to hack up vrp_meet. It's just
1956 easier to special case when vr0 is ~[0,0] for EXACT_DIV_EXPR. */
1957 if (code
== EXACT_DIV_EXPR
1958 && vr0
.type
== VR_ANTI_RANGE
1959 && vr0
.min
== vr0
.max
1960 && integer_zerop (vr0
.min
))
1962 set_value_range_to_nonnull (vr
, expr_type
);
1966 /* Now canonicalize anti-ranges to ranges when they are not symbolic
1967 and express ~[] op X as ([]' op X) U ([]'' op X). */
1968 if (vr0
.type
== VR_ANTI_RANGE
1969 && ranges_from_anti_range (&vr0
, &vrtem0
, &vrtem1
))
1971 extract_range_from_binary_expr_1 (vr
, code
, expr_type
, &vrtem0
, vr1_
);
1972 if (vrtem1
.type
!= VR_UNDEFINED
)
1974 value_range vrres
= VR_INITIALIZER
;
1975 extract_range_from_binary_expr_1 (&vrres
, code
, expr_type
,
1977 vrp_meet (vr
, &vrres
);
1981 /* Likewise for X op ~[]. */
1982 if (vr1
.type
== VR_ANTI_RANGE
1983 && ranges_from_anti_range (&vr1
, &vrtem0
, &vrtem1
))
1985 extract_range_from_binary_expr_1 (vr
, code
, expr_type
, vr0_
, &vrtem0
);
1986 if (vrtem1
.type
!= VR_UNDEFINED
)
1988 value_range vrres
= VR_INITIALIZER
;
1989 extract_range_from_binary_expr_1 (&vrres
, code
, expr_type
,
1991 vrp_meet (vr
, &vrres
);
1996 /* The type of the resulting value range defaults to VR0.TYPE. */
1999 /* Refuse to operate on VARYING ranges, ranges of different kinds
2000 and symbolic ranges. As an exception, we allow BIT_{AND,IOR}
2001 because we may be able to derive a useful range even if one of
2002 the operands is VR_VARYING or symbolic range. Similarly for
2003 divisions, MIN/MAX and PLUS/MINUS.
2005 TODO, we may be able to derive anti-ranges in some cases. */
2006 if (code
!= BIT_AND_EXPR
2007 && code
!= BIT_IOR_EXPR
2008 && code
!= TRUNC_DIV_EXPR
2009 && code
!= FLOOR_DIV_EXPR
2010 && code
!= CEIL_DIV_EXPR
2011 && code
!= EXACT_DIV_EXPR
2012 && code
!= ROUND_DIV_EXPR
2013 && code
!= TRUNC_MOD_EXPR
2016 && code
!= PLUS_EXPR
2017 && code
!= MINUS_EXPR
2018 && code
!= RSHIFT_EXPR
2019 && (vr0
.type
== VR_VARYING
2020 || vr1
.type
== VR_VARYING
2021 || vr0
.type
!= vr1
.type
2022 || symbolic_range_p (&vr0
)
2023 || symbolic_range_p (&vr1
)))
2025 set_value_range_to_varying (vr
);
2029 /* Now evaluate the expression to determine the new range. */
2030 if (POINTER_TYPE_P (expr_type
))
2032 if (code
== MIN_EXPR
|| code
== MAX_EXPR
)
2034 /* For MIN/MAX expressions with pointers, we only care about
2035 nullness, if both are non null, then the result is nonnull.
2036 If both are null, then the result is null. Otherwise they
2038 if (range_is_nonnull (&vr0
) && range_is_nonnull (&vr1
))
2039 set_value_range_to_nonnull (vr
, expr_type
);
2040 else if (range_is_null (&vr0
) && range_is_null (&vr1
))
2041 set_value_range_to_null (vr
, expr_type
);
2043 set_value_range_to_varying (vr
);
2045 else if (code
== POINTER_PLUS_EXPR
)
2047 /* For pointer types, we are really only interested in asserting
2048 whether the expression evaluates to non-NULL. */
2049 if (range_is_nonnull (&vr0
) || range_is_nonnull (&vr1
))
2050 set_value_range_to_nonnull (vr
, expr_type
);
2051 else if (range_is_null (&vr0
) && range_is_null (&vr1
))
2052 set_value_range_to_null (vr
, expr_type
);
2054 set_value_range_to_varying (vr
);
2056 else if (code
== BIT_AND_EXPR
)
2058 /* For pointer types, we are really only interested in asserting
2059 whether the expression evaluates to non-NULL. */
2060 if (range_is_nonnull (&vr0
) && range_is_nonnull (&vr1
))
2061 set_value_range_to_nonnull (vr
, expr_type
);
2062 else if (range_is_null (&vr0
) || range_is_null (&vr1
))
2063 set_value_range_to_null (vr
, expr_type
);
2065 set_value_range_to_varying (vr
);
2068 set_value_range_to_varying (vr
);
2073 /* For integer ranges, apply the operation to each end of the
2074 range and see what we end up with. */
2075 if (code
== PLUS_EXPR
|| code
== MINUS_EXPR
)
2077 const bool minus_p
= (code
== MINUS_EXPR
);
2078 tree min_op0
= vr0
.min
;
2079 tree min_op1
= minus_p
? vr1
.max
: vr1
.min
;
2080 tree max_op0
= vr0
.max
;
2081 tree max_op1
= minus_p
? vr1
.min
: vr1
.max
;
2082 tree sym_min_op0
= NULL_TREE
;
2083 tree sym_min_op1
= NULL_TREE
;
2084 tree sym_max_op0
= NULL_TREE
;
2085 tree sym_max_op1
= NULL_TREE
;
2086 bool neg_min_op0
, neg_min_op1
, neg_max_op0
, neg_max_op1
;
2088 /* If we have a PLUS or MINUS with two VR_RANGEs, either constant or
2089 single-symbolic ranges, try to compute the precise resulting range,
2090 but only if we know that this resulting range will also be constant
2091 or single-symbolic. */
2092 if (vr0
.type
== VR_RANGE
&& vr1
.type
== VR_RANGE
2093 && (TREE_CODE (min_op0
) == INTEGER_CST
2095 = get_single_symbol (min_op0
, &neg_min_op0
, &min_op0
)))
2096 && (TREE_CODE (min_op1
) == INTEGER_CST
2098 = get_single_symbol (min_op1
, &neg_min_op1
, &min_op1
)))
2099 && (!(sym_min_op0
&& sym_min_op1
)
2100 || (sym_min_op0
== sym_min_op1
2101 && neg_min_op0
== (minus_p
? neg_min_op1
: !neg_min_op1
)))
2102 && (TREE_CODE (max_op0
) == INTEGER_CST
2104 = get_single_symbol (max_op0
, &neg_max_op0
, &max_op0
)))
2105 && (TREE_CODE (max_op1
) == INTEGER_CST
2107 = get_single_symbol (max_op1
, &neg_max_op1
, &max_op1
)))
2108 && (!(sym_max_op0
&& sym_max_op1
)
2109 || (sym_max_op0
== sym_max_op1
2110 && neg_max_op0
== (minus_p
? neg_max_op1
: !neg_max_op1
))))
2112 const signop sgn
= TYPE_SIGN (expr_type
);
2113 const unsigned int prec
= TYPE_PRECISION (expr_type
);
2114 wide_int type_min
, type_max
, wmin
, wmax
;
2118 /* Get the lower and upper bounds of the type. */
2119 if (TYPE_OVERFLOW_WRAPS (expr_type
))
2121 type_min
= wi::min_value (prec
, sgn
);
2122 type_max
= wi::max_value (prec
, sgn
);
2126 type_min
= wi::to_wide (vrp_val_min (expr_type
));
2127 type_max
= wi::to_wide (vrp_val_max (expr_type
));
2130 /* Combine the lower bounds, if any. */
2131 if (min_op0
&& min_op1
)
2135 wmin
= wi::to_wide (min_op0
) - wi::to_wide (min_op1
);
2137 /* Check for overflow. */
2138 if (wi::cmp (0, wi::to_wide (min_op1
), sgn
)
2139 != wi::cmp (wmin
, wi::to_wide (min_op0
), sgn
))
2140 min_ovf
= wi::cmp (wi::to_wide (min_op0
),
2141 wi::to_wide (min_op1
), sgn
);
2145 wmin
= wi::to_wide (min_op0
) + wi::to_wide (min_op1
);
2147 /* Check for overflow. */
2148 if (wi::cmp (wi::to_wide (min_op1
), 0, sgn
)
2149 != wi::cmp (wmin
, wi::to_wide (min_op0
), sgn
))
2150 min_ovf
= wi::cmp (wi::to_wide (min_op0
), wmin
, sgn
);
2154 wmin
= wi::to_wide (min_op0
);
2159 wmin
= -wi::to_wide (min_op1
);
2161 /* Check for overflow. */
2163 && wi::neg_p (wi::to_wide (min_op1
))
2164 && wi::neg_p (wmin
))
2166 else if (sgn
== UNSIGNED
&& wi::to_wide (min_op1
) != 0)
2170 wmin
= wi::to_wide (min_op1
);
2173 wmin
= wi::shwi (0, prec
);
2175 /* Combine the upper bounds, if any. */
2176 if (max_op0
&& max_op1
)
2180 wmax
= wi::to_wide (max_op0
) - wi::to_wide (max_op1
);
2182 /* Check for overflow. */
2183 if (wi::cmp (0, wi::to_wide (max_op1
), sgn
)
2184 != wi::cmp (wmax
, wi::to_wide (max_op0
), sgn
))
2185 max_ovf
= wi::cmp (wi::to_wide (max_op0
),
2186 wi::to_wide (max_op1
), sgn
);
2190 wmax
= wi::to_wide (max_op0
) + wi::to_wide (max_op1
);
2192 if (wi::cmp (wi::to_wide (max_op1
), 0, sgn
)
2193 != wi::cmp (wmax
, wi::to_wide (max_op0
), sgn
))
2194 max_ovf
= wi::cmp (wi::to_wide (max_op0
), wmax
, sgn
);
2198 wmax
= wi::to_wide (max_op0
);
2203 wmax
= -wi::to_wide (max_op1
);
2205 /* Check for overflow. */
2207 && wi::neg_p (wi::to_wide (max_op1
))
2208 && wi::neg_p (wmax
))
2210 else if (sgn
== UNSIGNED
&& wi::to_wide (max_op1
) != 0)
2214 wmax
= wi::to_wide (max_op1
);
2217 wmax
= wi::shwi (0, prec
);
2219 /* Check for type overflow. */
2222 if (wi::cmp (wmin
, type_min
, sgn
) == -1)
2224 else if (wi::cmp (wmin
, type_max
, sgn
) == 1)
2229 if (wi::cmp (wmax
, type_min
, sgn
) == -1)
2231 else if (wi::cmp (wmax
, type_max
, sgn
) == 1)
2235 /* If we have overflow for the constant part and the resulting
2236 range will be symbolic, drop to VR_VARYING. */
2237 if ((min_ovf
&& sym_min_op0
!= sym_min_op1
)
2238 || (max_ovf
&& sym_max_op0
!= sym_max_op1
))
2240 set_value_range_to_varying (vr
);
2244 if (TYPE_OVERFLOW_WRAPS (expr_type
))
2246 /* If overflow wraps, truncate the values and adjust the
2247 range kind and bounds appropriately. */
2248 wide_int tmin
= wide_int::from (wmin
, prec
, sgn
);
2249 wide_int tmax
= wide_int::from (wmax
, prec
, sgn
);
2250 if (min_ovf
== max_ovf
)
2252 /* No overflow or both overflow or underflow. The
2253 range kind stays VR_RANGE. */
2254 min
= wide_int_to_tree (expr_type
, tmin
);
2255 max
= wide_int_to_tree (expr_type
, tmax
);
2257 else if ((min_ovf
== -1 && max_ovf
== 0)
2258 || (max_ovf
== 1 && min_ovf
== 0))
2260 /* Min underflow or max overflow. The range kind
2261 changes to VR_ANTI_RANGE. */
2262 bool covers
= false;
2263 wide_int tem
= tmin
;
2264 type
= VR_ANTI_RANGE
;
2266 if (wi::cmp (tmin
, tmax
, sgn
) < 0)
2269 if (wi::cmp (tmax
, tem
, sgn
) > 0)
2271 /* If the anti-range would cover nothing, drop to varying.
2272 Likewise if the anti-range bounds are outside of the
2274 if (covers
|| wi::cmp (tmin
, tmax
, sgn
) > 0)
2276 set_value_range_to_varying (vr
);
2279 min
= wide_int_to_tree (expr_type
, tmin
);
2280 max
= wide_int_to_tree (expr_type
, tmax
);
2284 /* Other underflow and/or overflow, drop to VR_VARYING. */
2285 set_value_range_to_varying (vr
);
2291 /* If overflow does not wrap, saturate to the types min/max
2294 min
= wide_int_to_tree (expr_type
, type_min
);
2295 else if (min_ovf
== 1)
2296 min
= wide_int_to_tree (expr_type
, type_max
);
2298 min
= wide_int_to_tree (expr_type
, wmin
);
2301 max
= wide_int_to_tree (expr_type
, type_min
);
2302 else if (max_ovf
== 1)
2303 max
= wide_int_to_tree (expr_type
, type_max
);
2305 max
= wide_int_to_tree (expr_type
, wmax
);
2308 /* If the result lower bound is constant, we're done;
2309 otherwise, build the symbolic lower bound. */
2310 if (sym_min_op0
== sym_min_op1
)
2312 else if (sym_min_op0
)
2313 min
= build_symbolic_expr (expr_type
, sym_min_op0
,
2315 else if (sym_min_op1
)
2317 /* We may not negate if that might introduce
2318 undefined overflow. */
2321 || TYPE_OVERFLOW_WRAPS (expr_type
))
2322 min
= build_symbolic_expr (expr_type
, sym_min_op1
,
2323 neg_min_op1
^ minus_p
, min
);
2328 /* Likewise for the upper bound. */
2329 if (sym_max_op0
== sym_max_op1
)
2331 else if (sym_max_op0
)
2332 max
= build_symbolic_expr (expr_type
, sym_max_op0
,
2334 else if (sym_max_op1
)
2336 /* We may not negate if that might introduce
2337 undefined overflow. */
2340 || TYPE_OVERFLOW_WRAPS (expr_type
))
2341 max
= build_symbolic_expr (expr_type
, sym_max_op1
,
2342 neg_max_op1
^ minus_p
, max
);
2349 /* For other cases, for example if we have a PLUS_EXPR with two
2350 VR_ANTI_RANGEs, drop to VR_VARYING. It would take more effort
2351 to compute a precise range for such a case.
2352 ??? General even mixed range kind operations can be expressed
2353 by for example transforming ~[3, 5] + [1, 2] to range-only
2354 operations and a union primitive:
2355 [-INF, 2] + [1, 2] U [5, +INF] + [1, 2]
2356 [-INF+1, 4] U [6, +INF(OVF)]
2357 though usually the union is not exactly representable with
2358 a single range or anti-range as the above is
2359 [-INF+1, +INF(OVF)] intersected with ~[5, 5]
2360 but one could use a scheme similar to equivalences for this. */
2361 set_value_range_to_varying (vr
);
2365 else if (code
== MIN_EXPR
2366 || code
== MAX_EXPR
)
2368 if (vr0
.type
== VR_RANGE
2369 && !symbolic_range_p (&vr0
))
2372 if (vr1
.type
== VR_RANGE
2373 && !symbolic_range_p (&vr1
))
2375 /* For operations that make the resulting range directly
2376 proportional to the original ranges, apply the operation to
2377 the same end of each range. */
2378 min
= int_const_binop (code
, vr0
.min
, vr1
.min
);
2379 max
= int_const_binop (code
, vr0
.max
, vr1
.max
);
2381 else if (code
== MIN_EXPR
)
2383 min
= vrp_val_min (expr_type
);
2386 else if (code
== MAX_EXPR
)
2389 max
= vrp_val_max (expr_type
);
2392 else if (vr1
.type
== VR_RANGE
2393 && !symbolic_range_p (&vr1
))
2396 if (code
== MIN_EXPR
)
2398 min
= vrp_val_min (expr_type
);
2401 else if (code
== MAX_EXPR
)
2404 max
= vrp_val_max (expr_type
);
2409 set_value_range_to_varying (vr
);
2413 else if (code
== MULT_EXPR
)
2415 /* Fancy code so that with unsigned, [-3,-1]*[-3,-1] does not
2416 drop to varying. This test requires 2*prec bits if both
2417 operands are signed and 2*prec + 2 bits if either is not. */
2419 signop sign
= TYPE_SIGN (expr_type
);
2420 unsigned int prec
= TYPE_PRECISION (expr_type
);
2422 if (!range_int_cst_p (&vr0
)
2423 || !range_int_cst_p (&vr1
))
2425 set_value_range_to_varying (vr
);
2429 if (TYPE_OVERFLOW_WRAPS (expr_type
))
2431 typedef FIXED_WIDE_INT (WIDE_INT_MAX_PRECISION
* 2) vrp_int
;
2432 typedef generic_wide_int
2433 <wi::extended_tree
<WIDE_INT_MAX_PRECISION
* 2> > vrp_int_cst
;
2434 vrp_int sizem1
= wi::mask
<vrp_int
> (prec
, false);
2435 vrp_int size
= sizem1
+ 1;
2437 /* Extend the values using the sign of the result to PREC2.
2438 From here on out, everthing is just signed math no matter
2439 what the input types were. */
2440 vrp_int min0
= vrp_int_cst (vr0
.min
);
2441 vrp_int max0
= vrp_int_cst (vr0
.max
);
2442 vrp_int min1
= vrp_int_cst (vr1
.min
);
2443 vrp_int max1
= vrp_int_cst (vr1
.max
);
2444 /* Canonicalize the intervals. */
2445 if (sign
== UNSIGNED
)
2447 if (wi::ltu_p (size
, min0
+ max0
))
2453 if (wi::ltu_p (size
, min1
+ max1
))
2460 vrp_int prod0
= min0
* min1
;
2461 vrp_int prod1
= min0
* max1
;
2462 vrp_int prod2
= max0
* min1
;
2463 vrp_int prod3
= max0
* max1
;
2465 /* Sort the 4 products so that min is in prod0 and max is in
2467 /* min0min1 > max0max1 */
2469 std::swap (prod0
, prod3
);
2471 /* min0max1 > max0min1 */
2473 std::swap (prod1
, prod2
);
2476 std::swap (prod0
, prod1
);
2479 std::swap (prod2
, prod3
);
2481 /* diff = max - min. */
2482 prod2
= prod3
- prod0
;
2483 if (wi::geu_p (prod2
, sizem1
))
2485 /* the range covers all values. */
2486 set_value_range_to_varying (vr
);
2490 /* The following should handle the wrapping and selecting
2491 VR_ANTI_RANGE for us. */
2492 min
= wide_int_to_tree (expr_type
, prod0
);
2493 max
= wide_int_to_tree (expr_type
, prod3
);
2494 set_and_canonicalize_value_range (vr
, VR_RANGE
, min
, max
, NULL
);
2498 /* If we have an unsigned MULT_EXPR with two VR_ANTI_RANGEs,
2499 drop to VR_VARYING. It would take more effort to compute a
2500 precise range for such a case. For example, if we have
2501 op0 == 65536 and op1 == 65536 with their ranges both being
2502 ~[0,0] on a 32-bit machine, we would have op0 * op1 == 0, so
2503 we cannot claim that the product is in ~[0,0]. Note that we
2504 are guaranteed to have vr0.type == vr1.type at this
2506 if (vr0
.type
== VR_ANTI_RANGE
2507 && !TYPE_OVERFLOW_UNDEFINED (expr_type
))
2509 set_value_range_to_varying (vr
);
2513 extract_range_from_multiplicative_op_1 (vr
, code
, &vr0
, &vr1
);
2516 else if (code
== RSHIFT_EXPR
2517 || code
== LSHIFT_EXPR
)
2519 /* If we have a RSHIFT_EXPR with any shift values outside [0..prec-1],
2520 then drop to VR_VARYING. Outside of this range we get undefined
2521 behavior from the shift operation. We cannot even trust
2522 SHIFT_COUNT_TRUNCATED at this stage, because that applies to rtl
2523 shifts, and the operation at the tree level may be widened. */
2524 if (range_int_cst_p (&vr1
)
2525 && compare_tree_int (vr1
.min
, 0) >= 0
2526 && compare_tree_int (vr1
.max
, TYPE_PRECISION (expr_type
)) == -1)
2528 if (code
== RSHIFT_EXPR
)
2530 /* Even if vr0 is VARYING or otherwise not usable, we can derive
2531 useful ranges just from the shift count. E.g.
2532 x >> 63 for signed 64-bit x is always [-1, 0]. */
2533 if (vr0
.type
!= VR_RANGE
|| symbolic_range_p (&vr0
))
2535 vr0
.type
= type
= VR_RANGE
;
2536 vr0
.min
= vrp_val_min (expr_type
);
2537 vr0
.max
= vrp_val_max (expr_type
);
2539 extract_range_from_multiplicative_op_1 (vr
, code
, &vr0
, &vr1
);
2542 /* We can map lshifts by constants to MULT_EXPR handling. */
2543 else if (code
== LSHIFT_EXPR
2544 && range_int_cst_singleton_p (&vr1
))
2546 bool saved_flag_wrapv
;
2547 value_range vr1p
= VR_INITIALIZER
;
2548 vr1p
.type
= VR_RANGE
;
2549 vr1p
.min
= (wide_int_to_tree
2551 wi::set_bit_in_zero (tree_to_shwi (vr1
.min
),
2552 TYPE_PRECISION (expr_type
))));
2553 vr1p
.max
= vr1p
.min
;
2554 /* We have to use a wrapping multiply though as signed overflow
2555 on lshifts is implementation defined in C89. */
2556 saved_flag_wrapv
= flag_wrapv
;
2558 extract_range_from_binary_expr_1 (vr
, MULT_EXPR
, expr_type
,
2560 flag_wrapv
= saved_flag_wrapv
;
2563 else if (code
== LSHIFT_EXPR
2564 && range_int_cst_p (&vr0
))
2566 int prec
= TYPE_PRECISION (expr_type
);
2567 int overflow_pos
= prec
;
2569 wide_int low_bound
, high_bound
;
2570 bool uns
= TYPE_UNSIGNED (expr_type
);
2571 bool in_bounds
= false;
2576 bound_shift
= overflow_pos
- tree_to_shwi (vr1
.max
);
2577 /* If bound_shift == HOST_BITS_PER_WIDE_INT, the llshift can
2578 overflow. However, for that to happen, vr1.max needs to be
2579 zero, which means vr1 is a singleton range of zero, which
2580 means it should be handled by the previous LSHIFT_EXPR
2582 wide_int bound
= wi::set_bit_in_zero (bound_shift
, prec
);
2583 wide_int complement
= ~(bound
- 1);
2588 high_bound
= complement
;
2589 if (wi::ltu_p (wi::to_wide (vr0
.max
), low_bound
))
2591 /* [5, 6] << [1, 2] == [10, 24]. */
2592 /* We're shifting out only zeroes, the value increases
2596 else if (wi::ltu_p (high_bound
, wi::to_wide (vr0
.min
)))
2598 /* [0xffffff00, 0xffffffff] << [1, 2]
2599 == [0xfffffc00, 0xfffffffe]. */
2600 /* We're shifting out only ones, the value decreases
2607 /* [-1, 1] << [1, 2] == [-4, 4]. */
2608 low_bound
= complement
;
2610 if (wi::lts_p (wi::to_wide (vr0
.max
), high_bound
)
2611 && wi::lts_p (low_bound
, wi::to_wide (vr0
.min
)))
2613 /* For non-negative numbers, we're shifting out only
2614 zeroes, the value increases monotonically.
2615 For negative numbers, we're shifting out only ones, the
2616 value decreases monotomically. */
2623 extract_range_from_multiplicative_op_1 (vr
, code
, &vr0
, &vr1
);
2628 set_value_range_to_varying (vr
);
2631 else if (code
== TRUNC_DIV_EXPR
2632 || code
== FLOOR_DIV_EXPR
2633 || code
== CEIL_DIV_EXPR
2634 || code
== EXACT_DIV_EXPR
2635 || code
== ROUND_DIV_EXPR
)
2637 if (vr0
.type
!= VR_RANGE
|| symbolic_range_p (&vr0
))
2639 /* For division, if op1 has VR_RANGE but op0 does not, something
2640 can be deduced just from that range. Say [min, max] / [4, max]
2641 gives [min / 4, max / 4] range. */
2642 if (vr1
.type
== VR_RANGE
2643 && !symbolic_range_p (&vr1
)
2644 && range_includes_zero_p (vr1
.min
, vr1
.max
) == 0)
2646 vr0
.type
= type
= VR_RANGE
;
2647 vr0
.min
= vrp_val_min (expr_type
);
2648 vr0
.max
= vrp_val_max (expr_type
);
2652 set_value_range_to_varying (vr
);
2657 /* For divisions, if flag_non_call_exceptions is true, we must
2658 not eliminate a division by zero. */
2659 if (cfun
->can_throw_non_call_exceptions
2660 && (vr1
.type
!= VR_RANGE
2661 || range_includes_zero_p (vr1
.min
, vr1
.max
) != 0))
2663 set_value_range_to_varying (vr
);
2667 /* For divisions, if op0 is VR_RANGE, we can deduce a range
2668 even if op1 is VR_VARYING, VR_ANTI_RANGE, symbolic or can
2670 if (vr0
.type
== VR_RANGE
2671 && (vr1
.type
!= VR_RANGE
2672 || range_includes_zero_p (vr1
.min
, vr1
.max
) != 0))
2674 tree zero
= build_int_cst (TREE_TYPE (vr0
.min
), 0);
2679 if (TYPE_UNSIGNED (expr_type
)
2680 || value_range_nonnegative_p (&vr1
))
2682 /* For unsigned division or when divisor is known
2683 to be non-negative, the range has to cover
2684 all numbers from 0 to max for positive max
2685 and all numbers from min to 0 for negative min. */
2686 cmp
= compare_values (vr0
.max
, zero
);
2689 /* When vr0.max < 0, vr1.min != 0 and value
2690 ranges for dividend and divisor are available. */
2691 if (vr1
.type
== VR_RANGE
2692 && !symbolic_range_p (&vr0
)
2693 && !symbolic_range_p (&vr1
)
2694 && compare_values (vr1
.min
, zero
) != 0)
2695 max
= int_const_binop (code
, vr0
.max
, vr1
.min
);
2699 else if (cmp
== 0 || cmp
== 1)
2703 cmp
= compare_values (vr0
.min
, zero
);
2706 /* For unsigned division when value ranges for dividend
2707 and divisor are available. */
2708 if (vr1
.type
== VR_RANGE
2709 && !symbolic_range_p (&vr0
)
2710 && !symbolic_range_p (&vr1
)
2711 && compare_values (vr1
.max
, zero
) != 0)
2712 min
= int_const_binop (code
, vr0
.min
, vr1
.max
);
2716 else if (cmp
== 0 || cmp
== -1)
2723 /* Otherwise the range is -max .. max or min .. -min
2724 depending on which bound is bigger in absolute value,
2725 as the division can change the sign. */
2726 abs_extent_range (vr
, vr0
.min
, vr0
.max
);
2729 if (type
== VR_VARYING
)
2731 set_value_range_to_varying (vr
);
2735 else if (!symbolic_range_p (&vr0
) && !symbolic_range_p (&vr1
))
2737 extract_range_from_multiplicative_op_1 (vr
, code
, &vr0
, &vr1
);
2741 else if (code
== TRUNC_MOD_EXPR
)
2743 if (range_is_null (&vr1
))
2745 set_value_range_to_undefined (vr
);
2748 /* ABS (A % B) < ABS (B) and either
2749 0 <= A % B <= A or A <= A % B <= 0. */
2751 signop sgn
= TYPE_SIGN (expr_type
);
2752 unsigned int prec
= TYPE_PRECISION (expr_type
);
2753 wide_int wmin
, wmax
, tmp
;
2754 if (vr1
.type
== VR_RANGE
&& !symbolic_range_p (&vr1
))
2756 wmax
= wi::to_wide (vr1
.max
) - 1;
2759 tmp
= -1 - wi::to_wide (vr1
.min
);
2760 wmax
= wi::smax (wmax
, tmp
);
2765 wmax
= wi::max_value (prec
, sgn
);
2766 /* X % INT_MIN may be INT_MAX. */
2767 if (sgn
== UNSIGNED
)
2771 if (sgn
== UNSIGNED
)
2772 wmin
= wi::zero (prec
);
2776 if (vr0
.type
== VR_RANGE
&& TREE_CODE (vr0
.min
) == INTEGER_CST
)
2778 tmp
= wi::to_wide (vr0
.min
);
2779 if (wi::gts_p (tmp
, 0))
2780 tmp
= wi::zero (prec
);
2781 wmin
= wi::smax (wmin
, tmp
);
2785 if (vr0
.type
== VR_RANGE
&& TREE_CODE (vr0
.max
) == INTEGER_CST
)
2787 tmp
= wi::to_wide (vr0
.max
);
2788 if (sgn
== SIGNED
&& wi::neg_p (tmp
))
2789 tmp
= wi::zero (prec
);
2790 wmax
= wi::min (wmax
, tmp
, sgn
);
2793 min
= wide_int_to_tree (expr_type
, wmin
);
2794 max
= wide_int_to_tree (expr_type
, wmax
);
2796 else if (code
== BIT_AND_EXPR
|| code
== BIT_IOR_EXPR
|| code
== BIT_XOR_EXPR
)
2798 bool int_cst_range0
, int_cst_range1
;
2799 wide_int may_be_nonzero0
, may_be_nonzero1
;
2800 wide_int must_be_nonzero0
, must_be_nonzero1
;
2802 int_cst_range0
= zero_nonzero_bits_from_vr (expr_type
, &vr0
,
2805 int_cst_range1
= zero_nonzero_bits_from_vr (expr_type
, &vr1
,
2809 if (code
== BIT_AND_EXPR
|| code
== BIT_IOR_EXPR
)
2811 value_range
*vr0p
= NULL
, *vr1p
= NULL
;
2812 if (range_int_cst_singleton_p (&vr1
))
2817 else if (range_int_cst_singleton_p (&vr0
))
2822 /* For op & or | attempt to optimize:
2823 [x, y] op z into [x op z, y op z]
2824 if z is a constant which (for op | its bitwise not) has n
2825 consecutive least significant bits cleared followed by m 1
2826 consecutive bits set immediately above it and either
2827 m + n == precision, or (x >> (m + n)) == (y >> (m + n)).
2828 The least significant n bits of all the values in the range are
2829 cleared or set, the m bits above it are preserved and any bits
2830 above these are required to be the same for all values in the
2832 if (vr0p
&& range_int_cst_p (vr0p
))
2834 wide_int w
= wi::to_wide (vr1p
->min
);
2836 if (code
== BIT_IOR_EXPR
)
2838 if (wi::eq_p (w
, 0))
2839 n
= TYPE_PRECISION (expr_type
);
2843 w
= ~(w
| wi::mask (n
, false, w
.get_precision ()));
2844 if (wi::eq_p (w
, 0))
2845 m
= TYPE_PRECISION (expr_type
) - n
;
2847 m
= wi::ctz (w
) - n
;
2849 wide_int mask
= wi::mask (m
+ n
, true, w
.get_precision ());
2850 if ((mask
& wi::to_wide (vr0p
->min
))
2851 == (mask
& wi::to_wide (vr0p
->max
)))
2853 min
= int_const_binop (code
, vr0p
->min
, vr1p
->min
);
2854 max
= int_const_binop (code
, vr0p
->max
, vr1p
->min
);
2861 /* Optimized above already. */;
2862 else if (code
== BIT_AND_EXPR
)
2864 min
= wide_int_to_tree (expr_type
,
2865 must_be_nonzero0
& must_be_nonzero1
);
2866 wide_int wmax
= may_be_nonzero0
& may_be_nonzero1
;
2867 /* If both input ranges contain only negative values we can
2868 truncate the result range maximum to the minimum of the
2869 input range maxima. */
2870 if (int_cst_range0
&& int_cst_range1
2871 && tree_int_cst_sgn (vr0
.max
) < 0
2872 && tree_int_cst_sgn (vr1
.max
) < 0)
2874 wmax
= wi::min (wmax
, wi::to_wide (vr0
.max
),
2875 TYPE_SIGN (expr_type
));
2876 wmax
= wi::min (wmax
, wi::to_wide (vr1
.max
),
2877 TYPE_SIGN (expr_type
));
2879 /* If either input range contains only non-negative values
2880 we can truncate the result range maximum to the respective
2881 maximum of the input range. */
2882 if (int_cst_range0
&& tree_int_cst_sgn (vr0
.min
) >= 0)
2883 wmax
= wi::min (wmax
, wi::to_wide (vr0
.max
),
2884 TYPE_SIGN (expr_type
));
2885 if (int_cst_range1
&& tree_int_cst_sgn (vr1
.min
) >= 0)
2886 wmax
= wi::min (wmax
, wi::to_wide (vr1
.max
),
2887 TYPE_SIGN (expr_type
));
2888 max
= wide_int_to_tree (expr_type
, wmax
);
2889 cmp
= compare_values (min
, max
);
2890 /* PR68217: In case of signed & sign-bit-CST should
2891 result in [-INF, 0] instead of [-INF, INF]. */
2892 if (cmp
== -2 || cmp
== 1)
2895 = wi::set_bit_in_zero (TYPE_PRECISION (expr_type
) - 1,
2896 TYPE_PRECISION (expr_type
));
2897 if (!TYPE_UNSIGNED (expr_type
)
2899 && value_range_constant_singleton (&vr0
)
2900 && !wi::cmps (wi::to_wide (vr0
.min
), sign_bit
))
2902 && value_range_constant_singleton (&vr1
)
2903 && !wi::cmps (wi::to_wide (vr1
.min
), sign_bit
))))
2905 min
= TYPE_MIN_VALUE (expr_type
);
2906 max
= build_int_cst (expr_type
, 0);
2910 else if (code
== BIT_IOR_EXPR
)
2912 max
= wide_int_to_tree (expr_type
,
2913 may_be_nonzero0
| may_be_nonzero1
);
2914 wide_int wmin
= must_be_nonzero0
| must_be_nonzero1
;
2915 /* If the input ranges contain only positive values we can
2916 truncate the minimum of the result range to the maximum
2917 of the input range minima. */
2918 if (int_cst_range0
&& int_cst_range1
2919 && tree_int_cst_sgn (vr0
.min
) >= 0
2920 && tree_int_cst_sgn (vr1
.min
) >= 0)
2922 wmin
= wi::max (wmin
, wi::to_wide (vr0
.min
),
2923 TYPE_SIGN (expr_type
));
2924 wmin
= wi::max (wmin
, wi::to_wide (vr1
.min
),
2925 TYPE_SIGN (expr_type
));
2927 /* If either input range contains only negative values
2928 we can truncate the minimum of the result range to the
2929 respective minimum range. */
2930 if (int_cst_range0
&& tree_int_cst_sgn (vr0
.max
) < 0)
2931 wmin
= wi::max (wmin
, wi::to_wide (vr0
.min
),
2932 TYPE_SIGN (expr_type
));
2933 if (int_cst_range1
&& tree_int_cst_sgn (vr1
.max
) < 0)
2934 wmin
= wi::max (wmin
, wi::to_wide (vr1
.min
),
2935 TYPE_SIGN (expr_type
));
2936 min
= wide_int_to_tree (expr_type
, wmin
);
2938 else if (code
== BIT_XOR_EXPR
)
2940 wide_int result_zero_bits
= ((must_be_nonzero0
& must_be_nonzero1
)
2941 | ~(may_be_nonzero0
| may_be_nonzero1
));
2942 wide_int result_one_bits
2943 = (wi::bit_and_not (must_be_nonzero0
, may_be_nonzero1
)
2944 | wi::bit_and_not (must_be_nonzero1
, may_be_nonzero0
));
2945 max
= wide_int_to_tree (expr_type
, ~result_zero_bits
);
2946 min
= wide_int_to_tree (expr_type
, result_one_bits
);
2947 /* If the range has all positive or all negative values the
2948 result is better than VARYING. */
2949 if (tree_int_cst_sgn (min
) < 0
2950 || tree_int_cst_sgn (max
) >= 0)
2953 max
= min
= NULL_TREE
;
2959 /* If either MIN or MAX overflowed, then set the resulting range to
2961 if (min
== NULL_TREE
2962 || TREE_OVERFLOW_P (min
)
2964 || TREE_OVERFLOW_P (max
))
2966 set_value_range_to_varying (vr
);
2970 /* We punt for [-INF, +INF].
2971 We learn nothing when we have INF on both sides.
2972 Note that we do accept [-INF, -INF] and [+INF, +INF]. */
2973 if (vrp_val_is_min (min
) && vrp_val_is_max (max
))
2975 set_value_range_to_varying (vr
);
2979 cmp
= compare_values (min
, max
);
2980 if (cmp
== -2 || cmp
== 1)
2982 /* If the new range has its limits swapped around (MIN > MAX),
2983 then the operation caused one of them to wrap around, mark
2984 the new range VARYING. */
2985 set_value_range_to_varying (vr
);
2988 set_value_range (vr
, type
, min
, max
, NULL
);
2991 /* Extract range information from a binary expression OP0 CODE OP1 based on
2992 the ranges of each of its operands with resulting type EXPR_TYPE.
2993 The resulting range is stored in *VR. */
2996 vr_values::extract_range_from_binary_expr (value_range
*vr
,
2997 enum tree_code code
,
2998 tree expr_type
, tree op0
, tree op1
)
3000 value_range vr0
= VR_INITIALIZER
;
3001 value_range vr1
= VR_INITIALIZER
;
3003 /* Get value ranges for each operand. For constant operands, create
3004 a new value range with the operand to simplify processing. */
3005 if (TREE_CODE (op0
) == SSA_NAME
)
3006 vr0
= *(get_value_range (op0
));
3007 else if (is_gimple_min_invariant (op0
))
3008 set_value_range_to_value (&vr0
, op0
, NULL
);
3010 set_value_range_to_varying (&vr0
);
3012 if (TREE_CODE (op1
) == SSA_NAME
)
3013 vr1
= *(get_value_range (op1
));
3014 else if (is_gimple_min_invariant (op1
))
3015 set_value_range_to_value (&vr1
, op1
, NULL
);
3017 set_value_range_to_varying (&vr1
);
3019 extract_range_from_binary_expr_1 (vr
, code
, expr_type
, &vr0
, &vr1
);
3021 /* Try harder for PLUS and MINUS if the range of one operand is symbolic
3022 and based on the other operand, for example if it was deduced from a
3023 symbolic comparison. When a bound of the range of the first operand
3024 is invariant, we set the corresponding bound of the new range to INF
3025 in order to avoid recursing on the range of the second operand. */
3026 if (vr
->type
== VR_VARYING
3027 && (code
== PLUS_EXPR
|| code
== MINUS_EXPR
)
3028 && TREE_CODE (op1
) == SSA_NAME
3029 && vr0
.type
== VR_RANGE
3030 && symbolic_range_based_on_p (&vr0
, op1
))
3032 const bool minus_p
= (code
== MINUS_EXPR
);
3033 value_range n_vr1
= VR_INITIALIZER
;
3035 /* Try with VR0 and [-INF, OP1]. */
3036 if (is_gimple_min_invariant (minus_p
? vr0
.max
: vr0
.min
))
3037 set_value_range (&n_vr1
, VR_RANGE
, vrp_val_min (expr_type
), op1
, NULL
);
3039 /* Try with VR0 and [OP1, +INF]. */
3040 else if (is_gimple_min_invariant (minus_p
? vr0
.min
: vr0
.max
))
3041 set_value_range (&n_vr1
, VR_RANGE
, op1
, vrp_val_max (expr_type
), NULL
);
3043 /* Try with VR0 and [OP1, OP1]. */
3045 set_value_range (&n_vr1
, VR_RANGE
, op1
, op1
, NULL
);
3047 extract_range_from_binary_expr_1 (vr
, code
, expr_type
, &vr0
, &n_vr1
);
3050 if (vr
->type
== VR_VARYING
3051 && (code
== PLUS_EXPR
|| code
== MINUS_EXPR
)
3052 && TREE_CODE (op0
) == SSA_NAME
3053 && vr1
.type
== VR_RANGE
3054 && symbolic_range_based_on_p (&vr1
, op0
))
3056 const bool minus_p
= (code
== MINUS_EXPR
);
3057 value_range n_vr0
= VR_INITIALIZER
;
3059 /* Try with [-INF, OP0] and VR1. */
3060 if (is_gimple_min_invariant (minus_p
? vr1
.max
: vr1
.min
))
3061 set_value_range (&n_vr0
, VR_RANGE
, vrp_val_min (expr_type
), op0
, NULL
);
3063 /* Try with [OP0, +INF] and VR1. */
3064 else if (is_gimple_min_invariant (minus_p
? vr1
.min
: vr1
.max
))
3065 set_value_range (&n_vr0
, VR_RANGE
, op0
, vrp_val_max (expr_type
), NULL
);
3067 /* Try with [OP0, OP0] and VR1. */
3069 set_value_range (&n_vr0
, VR_RANGE
, op0
, op0
, NULL
);
3071 extract_range_from_binary_expr_1 (vr
, code
, expr_type
, &n_vr0
, &vr1
);
3074 /* If we didn't derive a range for MINUS_EXPR, and
3075 op1's range is ~[op0,op0] or vice-versa, then we
3076 can derive a non-null range. This happens often for
3077 pointer subtraction. */
3078 if (vr
->type
== VR_VARYING
3079 && code
== MINUS_EXPR
3080 && TREE_CODE (op0
) == SSA_NAME
3081 && ((vr0
.type
== VR_ANTI_RANGE
3083 && vr0
.min
== vr0
.max
)
3084 || (vr1
.type
== VR_ANTI_RANGE
3086 && vr1
.min
== vr1
.max
)))
3087 set_value_range_to_nonnull (vr
, TREE_TYPE (op0
));
3090 /* Extract range information from a unary operation CODE based on
3091 the range of its operand *VR0 with type OP0_TYPE with resulting type TYPE.
3092 The resulting range is stored in *VR. */
3095 extract_range_from_unary_expr (value_range
*vr
,
3096 enum tree_code code
, tree type
,
3097 value_range
*vr0_
, tree op0_type
)
3099 value_range vr0
= *vr0_
, vrtem0
= VR_INITIALIZER
, vrtem1
= VR_INITIALIZER
;
3101 /* VRP only operates on integral and pointer types. */
3102 if (!(INTEGRAL_TYPE_P (op0_type
)
3103 || POINTER_TYPE_P (op0_type
))
3104 || !(INTEGRAL_TYPE_P (type
)
3105 || POINTER_TYPE_P (type
)))
3107 set_value_range_to_varying (vr
);
3111 /* If VR0 is UNDEFINED, so is the result. */
3112 if (vr0
.type
== VR_UNDEFINED
)
3114 set_value_range_to_undefined (vr
);
3118 /* Handle operations that we express in terms of others. */
3119 if (code
== PAREN_EXPR
|| code
== OBJ_TYPE_REF
)
3121 /* PAREN_EXPR and OBJ_TYPE_REF are simple copies. */
3122 copy_value_range (vr
, &vr0
);
3125 else if (code
== NEGATE_EXPR
)
3127 /* -X is simply 0 - X, so re-use existing code that also handles
3128 anti-ranges fine. */
3129 value_range zero
= VR_INITIALIZER
;
3130 set_value_range_to_value (&zero
, build_int_cst (type
, 0), NULL
);
3131 extract_range_from_binary_expr_1 (vr
, MINUS_EXPR
, type
, &zero
, &vr0
);
3134 else if (code
== BIT_NOT_EXPR
)
3136 /* ~X is simply -1 - X, so re-use existing code that also handles
3137 anti-ranges fine. */
3138 value_range minusone
= VR_INITIALIZER
;
3139 set_value_range_to_value (&minusone
, build_int_cst (type
, -1), NULL
);
3140 extract_range_from_binary_expr_1 (vr
, MINUS_EXPR
,
3141 type
, &minusone
, &vr0
);
3145 /* Now canonicalize anti-ranges to ranges when they are not symbolic
3146 and express op ~[] as (op []') U (op []''). */
3147 if (vr0
.type
== VR_ANTI_RANGE
3148 && ranges_from_anti_range (&vr0
, &vrtem0
, &vrtem1
))
3150 extract_range_from_unary_expr (vr
, code
, type
, &vrtem0
, op0_type
);
3151 if (vrtem1
.type
!= VR_UNDEFINED
)
3153 value_range vrres
= VR_INITIALIZER
;
3154 extract_range_from_unary_expr (&vrres
, code
, type
,
3156 vrp_meet (vr
, &vrres
);
3161 if (CONVERT_EXPR_CODE_P (code
))
3163 tree inner_type
= op0_type
;
3164 tree outer_type
= type
;
3166 /* If the expression evaluates to a pointer, we are only interested in
3167 determining if it evaluates to NULL [0, 0] or non-NULL (~[0, 0]). */
3168 if (POINTER_TYPE_P (type
))
3170 if (range_is_nonnull (&vr0
))
3171 set_value_range_to_nonnull (vr
, type
);
3172 else if (range_is_null (&vr0
))
3173 set_value_range_to_null (vr
, type
);
3175 set_value_range_to_varying (vr
);
3179 /* If VR0 is varying and we increase the type precision, assume
3180 a full range for the following transformation. */
3181 if (vr0
.type
== VR_VARYING
3182 && INTEGRAL_TYPE_P (inner_type
)
3183 && TYPE_PRECISION (inner_type
) < TYPE_PRECISION (outer_type
))
3185 vr0
.type
= VR_RANGE
;
3186 vr0
.min
= TYPE_MIN_VALUE (inner_type
);
3187 vr0
.max
= TYPE_MAX_VALUE (inner_type
);
3190 /* If VR0 is a constant range or anti-range and the conversion is
3191 not truncating we can convert the min and max values and
3192 canonicalize the resulting range. Otherwise we can do the
3193 conversion if the size of the range is less than what the
3194 precision of the target type can represent and the range is
3195 not an anti-range. */
3196 if ((vr0
.type
== VR_RANGE
3197 || vr0
.type
== VR_ANTI_RANGE
)
3198 && TREE_CODE (vr0
.min
) == INTEGER_CST
3199 && TREE_CODE (vr0
.max
) == INTEGER_CST
3200 && (TYPE_PRECISION (outer_type
) >= TYPE_PRECISION (inner_type
)
3201 || (vr0
.type
== VR_RANGE
3202 && integer_zerop (int_const_binop (RSHIFT_EXPR
,
3203 int_const_binop (MINUS_EXPR
, vr0
.max
, vr0
.min
),
3204 size_int (TYPE_PRECISION (outer_type
)))))))
3206 tree new_min
, new_max
;
3207 new_min
= force_fit_type (outer_type
, wi::to_widest (vr0
.min
),
3209 new_max
= force_fit_type (outer_type
, wi::to_widest (vr0
.max
),
3211 set_and_canonicalize_value_range (vr
, vr0
.type
,
3212 new_min
, new_max
, NULL
);
3216 set_value_range_to_varying (vr
);
3219 else if (code
== ABS_EXPR
)
3224 /* Pass through vr0 in the easy cases. */
3225 if (TYPE_UNSIGNED (type
)
3226 || value_range_nonnegative_p (&vr0
))
3228 copy_value_range (vr
, &vr0
);
3232 /* For the remaining varying or symbolic ranges we can't do anything
3234 if (vr0
.type
== VR_VARYING
3235 || symbolic_range_p (&vr0
))
3237 set_value_range_to_varying (vr
);
3241 /* -TYPE_MIN_VALUE = TYPE_MIN_VALUE with flag_wrapv so we can't get a
3243 if (!TYPE_OVERFLOW_UNDEFINED (type
)
3244 && ((vr0
.type
== VR_RANGE
3245 && vrp_val_is_min (vr0
.min
))
3246 || (vr0
.type
== VR_ANTI_RANGE
3247 && !vrp_val_is_min (vr0
.min
))))
3249 set_value_range_to_varying (vr
);
3253 /* ABS_EXPR may flip the range around, if the original range
3254 included negative values. */
3255 if (!vrp_val_is_min (vr0
.min
))
3256 min
= fold_unary_to_constant (code
, type
, vr0
.min
);
3258 min
= TYPE_MAX_VALUE (type
);
3260 if (!vrp_val_is_min (vr0
.max
))
3261 max
= fold_unary_to_constant (code
, type
, vr0
.max
);
3263 max
= TYPE_MAX_VALUE (type
);
3265 cmp
= compare_values (min
, max
);
3267 /* If a VR_ANTI_RANGEs contains zero, then we have
3268 ~[-INF, min(MIN, MAX)]. */
3269 if (vr0
.type
== VR_ANTI_RANGE
)
3271 if (range_includes_zero_p (vr0
.min
, vr0
.max
) == 1)
3273 /* Take the lower of the two values. */
3277 /* Create ~[-INF, min (abs(MIN), abs(MAX))]
3278 or ~[-INF + 1, min (abs(MIN), abs(MAX))] when
3279 flag_wrapv is set and the original anti-range doesn't include
3280 TYPE_MIN_VALUE, remember -TYPE_MIN_VALUE = TYPE_MIN_VALUE. */
3281 if (TYPE_OVERFLOW_WRAPS (type
))
3283 tree type_min_value
= TYPE_MIN_VALUE (type
);
3285 min
= (vr0
.min
!= type_min_value
3286 ? int_const_binop (PLUS_EXPR
, type_min_value
,
3287 build_int_cst (TREE_TYPE (type_min_value
), 1))
3291 min
= TYPE_MIN_VALUE (type
);
3295 /* All else has failed, so create the range [0, INF], even for
3296 flag_wrapv since TYPE_MIN_VALUE is in the original
3298 vr0
.type
= VR_RANGE
;
3299 min
= build_int_cst (type
, 0);
3300 max
= TYPE_MAX_VALUE (type
);
3304 /* If the range contains zero then we know that the minimum value in the
3305 range will be zero. */
3306 else if (range_includes_zero_p (vr0
.min
, vr0
.max
) == 1)
3310 min
= build_int_cst (type
, 0);
3314 /* If the range was reversed, swap MIN and MAX. */
3316 std::swap (min
, max
);
3319 cmp
= compare_values (min
, max
);
3320 if (cmp
== -2 || cmp
== 1)
3322 /* If the new range has its limits swapped around (MIN > MAX),
3323 then the operation caused one of them to wrap around, mark
3324 the new range VARYING. */
3325 set_value_range_to_varying (vr
);
3328 set_value_range (vr
, vr0
.type
, min
, max
, NULL
);
3332 /* For unhandled operations fall back to varying. */
3333 set_value_range_to_varying (vr
);
3338 /* Extract range information from a unary expression CODE OP0 based on
3339 the range of its operand with resulting type TYPE.
3340 The resulting range is stored in *VR. */
3343 vr_values::extract_range_from_unary_expr (value_range
*vr
, enum tree_code code
,
3344 tree type
, tree op0
)
3346 value_range vr0
= VR_INITIALIZER
;
3348 /* Get value ranges for the operand. For constant operands, create
3349 a new value range with the operand to simplify processing. */
3350 if (TREE_CODE (op0
) == SSA_NAME
)
3351 vr0
= *(get_value_range (op0
));
3352 else if (is_gimple_min_invariant (op0
))
3353 set_value_range_to_value (&vr0
, op0
, NULL
);
3355 set_value_range_to_varying (&vr0
);
3357 ::extract_range_from_unary_expr (vr
, code
, type
, &vr0
, TREE_TYPE (op0
));
3361 /* Extract range information from a conditional expression STMT based on
3362 the ranges of each of its operands and the expression code. */
3365 vr_values::extract_range_from_cond_expr (value_range
*vr
, gassign
*stmt
)
3368 value_range vr0
= VR_INITIALIZER
;
3369 value_range vr1
= VR_INITIALIZER
;
3371 /* Get value ranges for each operand. For constant operands, create
3372 a new value range with the operand to simplify processing. */
3373 op0
= gimple_assign_rhs2 (stmt
);
3374 if (TREE_CODE (op0
) == SSA_NAME
)
3375 vr0
= *(get_value_range (op0
));
3376 else if (is_gimple_min_invariant (op0
))
3377 set_value_range_to_value (&vr0
, op0
, NULL
);
3379 set_value_range_to_varying (&vr0
);
3381 op1
= gimple_assign_rhs3 (stmt
);
3382 if (TREE_CODE (op1
) == SSA_NAME
)
3383 vr1
= *(get_value_range (op1
));
3384 else if (is_gimple_min_invariant (op1
))
3385 set_value_range_to_value (&vr1
, op1
, NULL
);
3387 set_value_range_to_varying (&vr1
);
3389 /* The resulting value range is the union of the operand ranges */
3390 copy_value_range (vr
, &vr0
);
3391 vrp_meet (vr
, &vr1
);
3395 /* Extract range information from a comparison expression EXPR based
3396 on the range of its operand and the expression code. */
3399 vr_values::extract_range_from_comparison (value_range
*vr
, enum tree_code code
,
3400 tree type
, tree op0
, tree op1
)
3405 val
= vrp_evaluate_conditional_warnv_with_ops (code
, op0
, op1
, false, &sop
,
3409 /* Since this expression was found on the RHS of an assignment,
3410 its type may be different from _Bool. Convert VAL to EXPR's
3412 val
= fold_convert (type
, val
);
3413 if (is_gimple_min_invariant (val
))
3414 set_value_range_to_value (vr
, val
, vr
->equiv
);
3416 set_value_range (vr
, VR_RANGE
, val
, val
, vr
->equiv
);
3419 /* The result of a comparison is always true or false. */
3420 set_value_range_to_truthvalue (vr
, type
);
3423 /* Helper function for simplify_internal_call_using_ranges and
3424 extract_range_basic. Return true if OP0 SUBCODE OP1 for
3425 SUBCODE {PLUS,MINUS,MULT}_EXPR is known to never overflow or
3426 always overflow. Set *OVF to true if it is known to always
3430 vr_values::check_for_binary_op_overflow (enum tree_code subcode
, tree type
,
3431 tree op0
, tree op1
, bool *ovf
)
3433 value_range vr0
= VR_INITIALIZER
;
3434 value_range vr1
= VR_INITIALIZER
;
3435 if (TREE_CODE (op0
) == SSA_NAME
)
3436 vr0
= *get_value_range (op0
);
3437 else if (TREE_CODE (op0
) == INTEGER_CST
)
3438 set_value_range_to_value (&vr0
, op0
, NULL
);
3440 set_value_range_to_varying (&vr0
);
3442 if (TREE_CODE (op1
) == SSA_NAME
)
3443 vr1
= *get_value_range (op1
);
3444 else if (TREE_CODE (op1
) == INTEGER_CST
)
3445 set_value_range_to_value (&vr1
, op1
, NULL
);
3447 set_value_range_to_varying (&vr1
);
3449 if (!range_int_cst_p (&vr0
)
3450 || TREE_OVERFLOW (vr0
.min
)
3451 || TREE_OVERFLOW (vr0
.max
))
3453 vr0
.min
= vrp_val_min (TREE_TYPE (op0
));
3454 vr0
.max
= vrp_val_max (TREE_TYPE (op0
));
3456 if (!range_int_cst_p (&vr1
)
3457 || TREE_OVERFLOW (vr1
.min
)
3458 || TREE_OVERFLOW (vr1
.max
))
3460 vr1
.min
= vrp_val_min (TREE_TYPE (op1
));
3461 vr1
.max
= vrp_val_max (TREE_TYPE (op1
));
3463 *ovf
= arith_overflowed_p (subcode
, type
, vr0
.min
,
3464 subcode
== MINUS_EXPR
? vr1
.max
: vr1
.min
);
3465 if (arith_overflowed_p (subcode
, type
, vr0
.max
,
3466 subcode
== MINUS_EXPR
? vr1
.min
: vr1
.max
) != *ovf
)
3468 if (subcode
== MULT_EXPR
)
3470 if (arith_overflowed_p (subcode
, type
, vr0
.min
, vr1
.max
) != *ovf
3471 || arith_overflowed_p (subcode
, type
, vr0
.max
, vr1
.min
) != *ovf
)
3476 /* So far we found that there is an overflow on the boundaries.
3477 That doesn't prove that there is an overflow even for all values
3478 in between the boundaries. For that compute widest_int range
3479 of the result and see if it doesn't overlap the range of
3481 widest_int wmin
, wmax
;
3484 w
[0] = wi::to_widest (vr0
.min
);
3485 w
[1] = wi::to_widest (vr0
.max
);
3486 w
[2] = wi::to_widest (vr1
.min
);
3487 w
[3] = wi::to_widest (vr1
.max
);
3488 for (i
= 0; i
< 4; i
++)
3494 wt
= wi::add (w
[i
& 1], w
[2 + (i
& 2) / 2]);
3497 wt
= wi::sub (w
[i
& 1], w
[2 + (i
& 2) / 2]);
3500 wt
= wi::mul (w
[i
& 1], w
[2 + (i
& 2) / 2]);
3512 wmin
= wi::smin (wmin
, wt
);
3513 wmax
= wi::smax (wmax
, wt
);
3516 /* The result of op0 CODE op1 is known to be in range
3518 widest_int wtmin
= wi::to_widest (vrp_val_min (type
));
3519 widest_int wtmax
= wi::to_widest (vrp_val_max (type
));
3520 /* If all values in [wmin, wmax] are smaller than
3521 [wtmin, wtmax] or all are larger than [wtmin, wtmax],
3522 the arithmetic operation will always overflow. */
3523 if (wmax
< wtmin
|| wmin
> wtmax
)
3530 /* Try to derive a nonnegative or nonzero range out of STMT relying
3531 primarily on generic routines in fold in conjunction with range data.
3532 Store the result in *VR */
3535 vr_values::extract_range_basic (value_range
*vr
, gimple
*stmt
)
3538 tree type
= gimple_expr_type (stmt
);
3540 if (is_gimple_call (stmt
))
3543 int mini
, maxi
, zerov
= 0, prec
;
3544 enum tree_code subcode
= ERROR_MARK
;
3545 combined_fn cfn
= gimple_call_combined_fn (stmt
);
3546 scalar_int_mode mode
;
3550 case CFN_BUILT_IN_CONSTANT_P
:
3551 /* If the call is __builtin_constant_p and the argument is a
3552 function parameter resolve it to false. This avoids bogus
3553 array bound warnings.
3554 ??? We could do this as early as inlining is finished. */
3555 arg
= gimple_call_arg (stmt
, 0);
3556 if (TREE_CODE (arg
) == SSA_NAME
3557 && SSA_NAME_IS_DEFAULT_DEF (arg
)
3558 && TREE_CODE (SSA_NAME_VAR (arg
)) == PARM_DECL
3559 && cfun
->after_inlining
)
3561 set_value_range_to_null (vr
, type
);
3565 /* Both __builtin_ffs* and __builtin_popcount return
3569 arg
= gimple_call_arg (stmt
, 0);
3570 prec
= TYPE_PRECISION (TREE_TYPE (arg
));
3573 if (TREE_CODE (arg
) == SSA_NAME
)
3575 value_range
*vr0
= get_value_range (arg
);
3576 /* If arg is non-zero, then ffs or popcount
3578 if ((vr0
->type
== VR_RANGE
3579 && range_includes_zero_p (vr0
->min
, vr0
->max
) == 0)
3580 || (vr0
->type
== VR_ANTI_RANGE
3581 && range_includes_zero_p (vr0
->min
, vr0
->max
) == 1))
3583 /* If some high bits are known to be zero,
3584 we can decrease the maximum. */
3585 if (vr0
->type
== VR_RANGE
3586 && TREE_CODE (vr0
->max
) == INTEGER_CST
3587 && !operand_less_p (vr0
->min
,
3588 build_zero_cst (TREE_TYPE (vr0
->min
))))
3589 maxi
= tree_floor_log2 (vr0
->max
) + 1;
3592 /* __builtin_parity* returns [0, 1]. */
3597 /* __builtin_c[lt]z* return [0, prec-1], except for
3598 when the argument is 0, but that is undefined behavior.
3599 On many targets where the CLZ RTL or optab value is defined
3600 for 0 the value is prec, so include that in the range
3603 arg
= gimple_call_arg (stmt
, 0);
3604 prec
= TYPE_PRECISION (TREE_TYPE (arg
));
3607 mode
= SCALAR_INT_TYPE_MODE (TREE_TYPE (arg
));
3608 if (optab_handler (clz_optab
, mode
) != CODE_FOR_nothing
3609 && CLZ_DEFINED_VALUE_AT_ZERO (mode
, zerov
)
3610 /* Handle only the single common value. */
3612 /* Magic value to give up, unless vr0 proves
3615 if (TREE_CODE (arg
) == SSA_NAME
)
3617 value_range
*vr0
= get_value_range (arg
);
3618 /* From clz of VR_RANGE minimum we can compute
3620 if (vr0
->type
== VR_RANGE
3621 && TREE_CODE (vr0
->min
) == INTEGER_CST
)
3623 maxi
= prec
- 1 - tree_floor_log2 (vr0
->min
);
3627 else if (vr0
->type
== VR_ANTI_RANGE
3628 && integer_zerop (vr0
->min
))
3635 /* From clz of VR_RANGE maximum we can compute
3637 if (vr0
->type
== VR_RANGE
3638 && TREE_CODE (vr0
->max
) == INTEGER_CST
)
3640 mini
= prec
- 1 - tree_floor_log2 (vr0
->max
);
3648 /* __builtin_ctz* return [0, prec-1], except for
3649 when the argument is 0, but that is undefined behavior.
3650 If there is a ctz optab for this mode and
3651 CTZ_DEFINED_VALUE_AT_ZERO, include that in the range,
3652 otherwise just assume 0 won't be seen. */
3654 arg
= gimple_call_arg (stmt
, 0);
3655 prec
= TYPE_PRECISION (TREE_TYPE (arg
));
3658 mode
= SCALAR_INT_TYPE_MODE (TREE_TYPE (arg
));
3659 if (optab_handler (ctz_optab
, mode
) != CODE_FOR_nothing
3660 && CTZ_DEFINED_VALUE_AT_ZERO (mode
, zerov
))
3662 /* Handle only the two common values. */
3665 else if (zerov
== prec
)
3668 /* Magic value to give up, unless vr0 proves
3672 if (TREE_CODE (arg
) == SSA_NAME
)
3674 value_range
*vr0
= get_value_range (arg
);
3675 /* If arg is non-zero, then use [0, prec - 1]. */
3676 if ((vr0
->type
== VR_RANGE
3677 && integer_nonzerop (vr0
->min
))
3678 || (vr0
->type
== VR_ANTI_RANGE
3679 && integer_zerop (vr0
->min
)))
3684 /* If some high bits are known to be zero,
3685 we can decrease the result maximum. */
3686 if (vr0
->type
== VR_RANGE
3687 && TREE_CODE (vr0
->max
) == INTEGER_CST
)
3689 maxi
= tree_floor_log2 (vr0
->max
);
3690 /* For vr0 [0, 0] give up. */
3698 /* __builtin_clrsb* returns [0, prec-1]. */
3700 arg
= gimple_call_arg (stmt
, 0);
3701 prec
= TYPE_PRECISION (TREE_TYPE (arg
));
3706 set_value_range (vr
, VR_RANGE
, build_int_cst (type
, mini
),
3707 build_int_cst (type
, maxi
), NULL
);
3709 case CFN_UBSAN_CHECK_ADD
:
3710 subcode
= PLUS_EXPR
;
3712 case CFN_UBSAN_CHECK_SUB
:
3713 subcode
= MINUS_EXPR
;
3715 case CFN_UBSAN_CHECK_MUL
:
3716 subcode
= MULT_EXPR
;
3718 case CFN_GOACC_DIM_SIZE
:
3719 case CFN_GOACC_DIM_POS
:
3720 /* Optimizing these two internal functions helps the loop
3721 optimizer eliminate outer comparisons. Size is [1,N]
3722 and pos is [0,N-1]. */
3724 bool is_pos
= cfn
== CFN_GOACC_DIM_POS
;
3725 int axis
= oacc_get_ifn_dim_arg (stmt
);
3726 int size
= oacc_get_fn_dim_size (current_function_decl
, axis
);
3729 /* If it's dynamic, the backend might know a hardware
3731 size
= targetm
.goacc
.dim_limit (axis
);
3733 tree type
= TREE_TYPE (gimple_call_lhs (stmt
));
3734 set_value_range (vr
, VR_RANGE
,
3735 build_int_cst (type
, is_pos
? 0 : 1),
3736 size
? build_int_cst (type
, size
- is_pos
)
3737 : vrp_val_max (type
), NULL
);
3740 case CFN_BUILT_IN_STRLEN
:
3741 if (tree lhs
= gimple_call_lhs (stmt
))
3742 if (ptrdiff_type_node
3743 && (TYPE_PRECISION (ptrdiff_type_node
)
3744 == TYPE_PRECISION (TREE_TYPE (lhs
))))
3746 tree type
= TREE_TYPE (lhs
);
3747 tree max
= vrp_val_max (ptrdiff_type_node
);
3748 wide_int wmax
= wi::to_wide (max
, TYPE_PRECISION (TREE_TYPE (max
)));
3749 tree range_min
= build_zero_cst (type
);
3750 tree range_max
= wide_int_to_tree (type
, wmax
- 1);
3751 set_value_range (vr
, VR_RANGE
, range_min
, range_max
, NULL
);
3758 if (subcode
!= ERROR_MARK
)
3760 bool saved_flag_wrapv
= flag_wrapv
;
3761 /* Pretend the arithmetics is wrapping. If there is
3762 any overflow, we'll complain, but will actually do
3763 wrapping operation. */
3765 extract_range_from_binary_expr (vr
, subcode
, type
,
3766 gimple_call_arg (stmt
, 0),
3767 gimple_call_arg (stmt
, 1));
3768 flag_wrapv
= saved_flag_wrapv
;
3770 /* If for both arguments vrp_valueize returned non-NULL,
3771 this should have been already folded and if not, it
3772 wasn't folded because of overflow. Avoid removing the
3773 UBSAN_CHECK_* calls in that case. */
3774 if (vr
->type
== VR_RANGE
3775 && (vr
->min
== vr
->max
3776 || operand_equal_p (vr
->min
, vr
->max
, 0)))
3777 set_value_range_to_varying (vr
);
3781 /* Handle extraction of the two results (result of arithmetics and
3782 a flag whether arithmetics overflowed) from {ADD,SUB,MUL}_OVERFLOW
3783 internal function. Similarly from ATOMIC_COMPARE_EXCHANGE. */
3784 else if (is_gimple_assign (stmt
)
3785 && (gimple_assign_rhs_code (stmt
) == REALPART_EXPR
3786 || gimple_assign_rhs_code (stmt
) == IMAGPART_EXPR
)
3787 && INTEGRAL_TYPE_P (type
))
3789 enum tree_code code
= gimple_assign_rhs_code (stmt
);
3790 tree op
= gimple_assign_rhs1 (stmt
);
3791 if (TREE_CODE (op
) == code
&& TREE_CODE (TREE_OPERAND (op
, 0)) == SSA_NAME
)
3793 gimple
*g
= SSA_NAME_DEF_STMT (TREE_OPERAND (op
, 0));
3794 if (is_gimple_call (g
) && gimple_call_internal_p (g
))
3796 enum tree_code subcode
= ERROR_MARK
;
3797 switch (gimple_call_internal_fn (g
))
3799 case IFN_ADD_OVERFLOW
:
3800 subcode
= PLUS_EXPR
;
3802 case IFN_SUB_OVERFLOW
:
3803 subcode
= MINUS_EXPR
;
3805 case IFN_MUL_OVERFLOW
:
3806 subcode
= MULT_EXPR
;
3808 case IFN_ATOMIC_COMPARE_EXCHANGE
:
3809 if (code
== IMAGPART_EXPR
)
3811 /* This is the boolean return value whether compare and
3812 exchange changed anything or not. */
3813 set_value_range (vr
, VR_RANGE
, build_int_cst (type
, 0),
3814 build_int_cst (type
, 1), NULL
);
3821 if (subcode
!= ERROR_MARK
)
3823 tree op0
= gimple_call_arg (g
, 0);
3824 tree op1
= gimple_call_arg (g
, 1);
3825 if (code
== IMAGPART_EXPR
)
3828 if (check_for_binary_op_overflow (subcode
, type
,
3830 set_value_range_to_value (vr
,
3831 build_int_cst (type
, ovf
),
3833 else if (TYPE_PRECISION (type
) == 1
3834 && !TYPE_UNSIGNED (type
))
3835 set_value_range_to_varying (vr
);
3837 set_value_range (vr
, VR_RANGE
, build_int_cst (type
, 0),
3838 build_int_cst (type
, 1), NULL
);
3840 else if (types_compatible_p (type
, TREE_TYPE (op0
))
3841 && types_compatible_p (type
, TREE_TYPE (op1
)))
3843 bool saved_flag_wrapv
= flag_wrapv
;
3844 /* Pretend the arithmetics is wrapping. If there is
3845 any overflow, IMAGPART_EXPR will be set. */
3847 extract_range_from_binary_expr (vr
, subcode
, type
,
3849 flag_wrapv
= saved_flag_wrapv
;
3853 value_range vr0
= VR_INITIALIZER
;
3854 value_range vr1
= VR_INITIALIZER
;
3855 bool saved_flag_wrapv
= flag_wrapv
;
3856 /* Pretend the arithmetics is wrapping. If there is
3857 any overflow, IMAGPART_EXPR will be set. */
3859 extract_range_from_unary_expr (&vr0
, NOP_EXPR
,
3861 extract_range_from_unary_expr (&vr1
, NOP_EXPR
,
3863 extract_range_from_binary_expr_1 (vr
, subcode
, type
,
3865 flag_wrapv
= saved_flag_wrapv
;
3872 if (INTEGRAL_TYPE_P (type
)
3873 && gimple_stmt_nonnegative_warnv_p (stmt
, &sop
))
3874 set_value_range_to_nonnegative (vr
, type
);
3875 else if (vrp_stmt_computes_nonzero (stmt
))
3876 set_value_range_to_nonnull (vr
, type
);
3878 set_value_range_to_varying (vr
);
3882 /* Try to compute a useful range out of assignment STMT and store it
3886 vr_values::extract_range_from_assignment (value_range
*vr
, gassign
*stmt
)
3888 enum tree_code code
= gimple_assign_rhs_code (stmt
);
3890 if (code
== ASSERT_EXPR
)
3891 extract_range_from_assert (vr
, gimple_assign_rhs1 (stmt
));
3892 else if (code
== SSA_NAME
)
3893 extract_range_from_ssa_name (vr
, gimple_assign_rhs1 (stmt
));
3894 else if (TREE_CODE_CLASS (code
) == tcc_binary
)
3895 extract_range_from_binary_expr (vr
, gimple_assign_rhs_code (stmt
),
3896 gimple_expr_type (stmt
),
3897 gimple_assign_rhs1 (stmt
),
3898 gimple_assign_rhs2 (stmt
));
3899 else if (TREE_CODE_CLASS (code
) == tcc_unary
)
3900 extract_range_from_unary_expr (vr
, gimple_assign_rhs_code (stmt
),
3901 gimple_expr_type (stmt
),
3902 gimple_assign_rhs1 (stmt
));
3903 else if (code
== COND_EXPR
)
3904 extract_range_from_cond_expr (vr
, stmt
);
3905 else if (TREE_CODE_CLASS (code
) == tcc_comparison
)
3906 extract_range_from_comparison (vr
, gimple_assign_rhs_code (stmt
),
3907 gimple_expr_type (stmt
),
3908 gimple_assign_rhs1 (stmt
),
3909 gimple_assign_rhs2 (stmt
));
3910 else if (get_gimple_rhs_class (code
) == GIMPLE_SINGLE_RHS
3911 && is_gimple_min_invariant (gimple_assign_rhs1 (stmt
)))
3912 set_value_range_to_value (vr
, gimple_assign_rhs1 (stmt
), NULL
);
3914 set_value_range_to_varying (vr
);
3916 if (vr
->type
== VR_VARYING
)
3917 extract_range_basic (vr
, stmt
);
3920 /* Given a range VR, a LOOP and a variable VAR, determine whether it
3921 would be profitable to adjust VR using scalar evolution information
3922 for VAR. If so, update VR with the new limits. */
3925 vr_values::adjust_range_with_scev (value_range
*vr
, struct loop
*loop
,
3926 gimple
*stmt
, tree var
)
3928 tree init
, step
, chrec
, tmin
, tmax
, min
, max
, type
, tem
;
3929 enum ev_direction dir
;
3931 /* TODO. Don't adjust anti-ranges. An anti-range may provide
3932 better opportunities than a regular range, but I'm not sure. */
3933 if (vr
->type
== VR_ANTI_RANGE
)
3936 chrec
= instantiate_parameters (loop
, analyze_scalar_evolution (loop
, var
));
3938 /* Like in PR19590, scev can return a constant function. */
3939 if (is_gimple_min_invariant (chrec
))
3941 set_value_range_to_value (vr
, chrec
, vr
->equiv
);
3945 if (TREE_CODE (chrec
) != POLYNOMIAL_CHREC
)
3948 init
= initial_condition_in_loop_num (chrec
, loop
->num
);
3949 tem
= op_with_constant_singleton_value_range (init
);
3952 step
= evolution_part_in_loop_num (chrec
, loop
->num
);
3953 tem
= op_with_constant_singleton_value_range (step
);
3957 /* If STEP is symbolic, we can't know whether INIT will be the
3958 minimum or maximum value in the range. Also, unless INIT is
3959 a simple expression, compare_values and possibly other functions
3960 in tree-vrp won't be able to handle it. */
3961 if (step
== NULL_TREE
3962 || !is_gimple_min_invariant (step
)
3963 || !valid_value_p (init
))
3966 dir
= scev_direction (chrec
);
3967 if (/* Do not adjust ranges if we do not know whether the iv increases
3968 or decreases, ... */
3969 dir
== EV_DIR_UNKNOWN
3970 /* ... or if it may wrap. */
3971 || scev_probably_wraps_p (NULL_TREE
, init
, step
, stmt
,
3972 get_chrec_loop (chrec
), true))
3975 type
= TREE_TYPE (var
);
3976 if (POINTER_TYPE_P (type
) || !TYPE_MIN_VALUE (type
))
3977 tmin
= lower_bound_in_type (type
, type
);
3979 tmin
= TYPE_MIN_VALUE (type
);
3980 if (POINTER_TYPE_P (type
) || !TYPE_MAX_VALUE (type
))
3981 tmax
= upper_bound_in_type (type
, type
);
3983 tmax
= TYPE_MAX_VALUE (type
);
3985 /* Try to use estimated number of iterations for the loop to constrain the
3986 final value in the evolution. */
3987 if (TREE_CODE (step
) == INTEGER_CST
3988 && is_gimple_val (init
)
3989 && (TREE_CODE (init
) != SSA_NAME
3990 || get_value_range (init
)->type
== VR_RANGE
))
3994 /* We are only entering here for loop header PHI nodes, so using
3995 the number of latch executions is the correct thing to use. */
3996 if (max_loop_iterations (loop
, &nit
))
3998 value_range maxvr
= VR_INITIALIZER
;
3999 signop sgn
= TYPE_SIGN (TREE_TYPE (step
));
4002 widest_int wtmp
= wi::mul (wi::to_widest (step
), nit
, sgn
,
4004 /* If the multiplication overflowed we can't do a meaningful
4005 adjustment. Likewise if the result doesn't fit in the type
4006 of the induction variable. For a signed type we have to
4007 check whether the result has the expected signedness which
4008 is that of the step as number of iterations is unsigned. */
4010 && wi::fits_to_tree_p (wtmp
, TREE_TYPE (init
))
4012 || wi::gts_p (wtmp
, 0) == wi::gts_p (wi::to_wide (step
), 0)))
4014 tem
= wide_int_to_tree (TREE_TYPE (init
), wtmp
);
4015 extract_range_from_binary_expr (&maxvr
, PLUS_EXPR
,
4016 TREE_TYPE (init
), init
, tem
);
4017 /* Likewise if the addition did. */
4018 if (maxvr
.type
== VR_RANGE
)
4020 value_range initvr
= VR_INITIALIZER
;
4022 if (TREE_CODE (init
) == SSA_NAME
)
4023 initvr
= *(get_value_range (init
));
4024 else if (is_gimple_min_invariant (init
))
4025 set_value_range_to_value (&initvr
, init
, NULL
);
4029 /* Check if init + nit * step overflows. Though we checked
4030 scev {init, step}_loop doesn't wrap, it is not enough
4031 because the loop may exit immediately. Overflow could
4032 happen in the plus expression in this case. */
4033 if ((dir
== EV_DIR_DECREASES
4034 && compare_values (maxvr
.min
, initvr
.min
) != -1)
4035 || (dir
== EV_DIR_GROWS
4036 && compare_values (maxvr
.max
, initvr
.max
) != 1))
4046 if (vr
->type
== VR_VARYING
|| vr
->type
== VR_UNDEFINED
)
4051 /* For VARYING or UNDEFINED ranges, just about anything we get
4052 from scalar evolutions should be better. */
4054 if (dir
== EV_DIR_DECREASES
)
4059 else if (vr
->type
== VR_RANGE
)
4064 if (dir
== EV_DIR_DECREASES
)
4066 /* INIT is the maximum value. If INIT is lower than VR->MAX
4067 but no smaller than VR->MIN, set VR->MAX to INIT. */
4068 if (compare_values (init
, max
) == -1)
4071 /* According to the loop information, the variable does not
4073 if (compare_values (min
, tmin
) == -1)
4079 /* If INIT is bigger than VR->MIN, set VR->MIN to INIT. */
4080 if (compare_values (init
, min
) == 1)
4083 if (compare_values (tmax
, max
) == -1)
4090 /* If we just created an invalid range with the minimum
4091 greater than the maximum, we fail conservatively.
4092 This should happen only in unreachable
4093 parts of code, or for invalid programs. */
4094 if (compare_values (min
, max
) == 1)
4097 /* Even for valid range info, sometimes overflow flag will leak in.
4098 As GIMPLE IL should have no constants with TREE_OVERFLOW set, we
4100 if (TREE_OVERFLOW_P (min
))
4101 min
= drop_tree_overflow (min
);
4102 if (TREE_OVERFLOW_P (max
))
4103 max
= drop_tree_overflow (max
);
4105 set_value_range (vr
, VR_RANGE
, min
, max
, vr
->equiv
);
4109 /* Given two numeric value ranges VR0, VR1 and a comparison code COMP:
4111 - Return BOOLEAN_TRUE_NODE if VR0 COMP VR1 always returns true for
4112 all the values in the ranges.
4114 - Return BOOLEAN_FALSE_NODE if the comparison always returns false.
4116 - Return NULL_TREE if it is not always possible to determine the
4117 value of the comparison.
4119 Also set *STRICT_OVERFLOW_P to indicate whether comparision evaluation
4120 assumed signed overflow is undefined. */
4124 compare_ranges (enum tree_code comp
, value_range
*vr0
, value_range
*vr1
,
4125 bool *strict_overflow_p
)
4127 /* VARYING or UNDEFINED ranges cannot be compared. */
4128 if (vr0
->type
== VR_VARYING
4129 || vr0
->type
== VR_UNDEFINED
4130 || vr1
->type
== VR_VARYING
4131 || vr1
->type
== VR_UNDEFINED
)
4134 /* Anti-ranges need to be handled separately. */
4135 if (vr0
->type
== VR_ANTI_RANGE
|| vr1
->type
== VR_ANTI_RANGE
)
4137 /* If both are anti-ranges, then we cannot compute any
4139 if (vr0
->type
== VR_ANTI_RANGE
&& vr1
->type
== VR_ANTI_RANGE
)
4142 /* These comparisons are never statically computable. */
4149 /* Equality can be computed only between a range and an
4150 anti-range. ~[VAL1, VAL2] == [VAL1, VAL2] is always false. */
4151 if (vr0
->type
== VR_RANGE
)
4153 /* To simplify processing, make VR0 the anti-range. */
4154 value_range
*tmp
= vr0
;
4159 gcc_assert (comp
== NE_EXPR
|| comp
== EQ_EXPR
);
4161 if (compare_values_warnv (vr0
->min
, vr1
->min
, strict_overflow_p
) == 0
4162 && compare_values_warnv (vr0
->max
, vr1
->max
, strict_overflow_p
) == 0)
4163 return (comp
== NE_EXPR
) ? boolean_true_node
: boolean_false_node
;
4168 /* Simplify processing. If COMP is GT_EXPR or GE_EXPR, switch the
4169 operands around and change the comparison code. */
4170 if (comp
== GT_EXPR
|| comp
== GE_EXPR
)
4172 comp
= (comp
== GT_EXPR
) ? LT_EXPR
: LE_EXPR
;
4173 std::swap (vr0
, vr1
);
4176 if (comp
== EQ_EXPR
)
4178 /* Equality may only be computed if both ranges represent
4179 exactly one value. */
4180 if (compare_values_warnv (vr0
->min
, vr0
->max
, strict_overflow_p
) == 0
4181 && compare_values_warnv (vr1
->min
, vr1
->max
, strict_overflow_p
) == 0)
4183 int cmp_min
= compare_values_warnv (vr0
->min
, vr1
->min
,
4185 int cmp_max
= compare_values_warnv (vr0
->max
, vr1
->max
,
4187 if (cmp_min
== 0 && cmp_max
== 0)
4188 return boolean_true_node
;
4189 else if (cmp_min
!= -2 && cmp_max
!= -2)
4190 return boolean_false_node
;
4192 /* If [V0_MIN, V1_MAX] < [V1_MIN, V1_MAX] then V0 != V1. */
4193 else if (compare_values_warnv (vr0
->min
, vr1
->max
,
4194 strict_overflow_p
) == 1
4195 || compare_values_warnv (vr1
->min
, vr0
->max
,
4196 strict_overflow_p
) == 1)
4197 return boolean_false_node
;
4201 else if (comp
== NE_EXPR
)
4205 /* If VR0 is completely to the left or completely to the right
4206 of VR1, they are always different. Notice that we need to
4207 make sure that both comparisons yield similar results to
4208 avoid comparing values that cannot be compared at
4210 cmp1
= compare_values_warnv (vr0
->max
, vr1
->min
, strict_overflow_p
);
4211 cmp2
= compare_values_warnv (vr0
->min
, vr1
->max
, strict_overflow_p
);
4212 if ((cmp1
== -1 && cmp2
== -1) || (cmp1
== 1 && cmp2
== 1))
4213 return boolean_true_node
;
4215 /* If VR0 and VR1 represent a single value and are identical,
4217 else if (compare_values_warnv (vr0
->min
, vr0
->max
,
4218 strict_overflow_p
) == 0
4219 && compare_values_warnv (vr1
->min
, vr1
->max
,
4220 strict_overflow_p
) == 0
4221 && compare_values_warnv (vr0
->min
, vr1
->min
,
4222 strict_overflow_p
) == 0
4223 && compare_values_warnv (vr0
->max
, vr1
->max
,
4224 strict_overflow_p
) == 0)
4225 return boolean_false_node
;
4227 /* Otherwise, they may or may not be different. */
4231 else if (comp
== LT_EXPR
|| comp
== LE_EXPR
)
4235 /* If VR0 is to the left of VR1, return true. */
4236 tst
= compare_values_warnv (vr0
->max
, vr1
->min
, strict_overflow_p
);
4237 if ((comp
== LT_EXPR
&& tst
== -1)
4238 || (comp
== LE_EXPR
&& (tst
== -1 || tst
== 0)))
4239 return boolean_true_node
;
4241 /* If VR0 is to the right of VR1, return false. */
4242 tst
= compare_values_warnv (vr0
->min
, vr1
->max
, strict_overflow_p
);
4243 if ((comp
== LT_EXPR
&& (tst
== 0 || tst
== 1))
4244 || (comp
== LE_EXPR
&& tst
== 1))
4245 return boolean_false_node
;
4247 /* Otherwise, we don't know. */
4255 /* Given a value range VR, a value VAL and a comparison code COMP, return
4256 BOOLEAN_TRUE_NODE if VR COMP VAL always returns true for all the
4257 values in VR. Return BOOLEAN_FALSE_NODE if the comparison
4258 always returns false. Return NULL_TREE if it is not always
4259 possible to determine the value of the comparison. Also set
4260 *STRICT_OVERFLOW_P to indicate whether comparision evaluation
4261 assumed signed overflow is undefined. */
4264 compare_range_with_value (enum tree_code comp
, value_range
*vr
, tree val
,
4265 bool *strict_overflow_p
)
4267 if (vr
->type
== VR_VARYING
|| vr
->type
== VR_UNDEFINED
)
4270 /* Anti-ranges need to be handled separately. */
4271 if (vr
->type
== VR_ANTI_RANGE
)
4273 /* For anti-ranges, the only predicates that we can compute at
4274 compile time are equality and inequality. */
4281 /* ~[VAL_1, VAL_2] OP VAL is known if VAL_1 <= VAL <= VAL_2. */
4282 if (value_inside_range (val
, vr
->min
, vr
->max
) == 1)
4283 return (comp
== NE_EXPR
) ? boolean_true_node
: boolean_false_node
;
4288 if (comp
== EQ_EXPR
)
4290 /* EQ_EXPR may only be computed if VR represents exactly
4292 if (compare_values_warnv (vr
->min
, vr
->max
, strict_overflow_p
) == 0)
4294 int cmp
= compare_values_warnv (vr
->min
, val
, strict_overflow_p
);
4296 return boolean_true_node
;
4297 else if (cmp
== -1 || cmp
== 1 || cmp
== 2)
4298 return boolean_false_node
;
4300 else if (compare_values_warnv (val
, vr
->min
, strict_overflow_p
) == -1
4301 || compare_values_warnv (vr
->max
, val
, strict_overflow_p
) == -1)
4302 return boolean_false_node
;
4306 else if (comp
== NE_EXPR
)
4308 /* If VAL is not inside VR, then they are always different. */
4309 if (compare_values_warnv (vr
->max
, val
, strict_overflow_p
) == -1
4310 || compare_values_warnv (vr
->min
, val
, strict_overflow_p
) == 1)
4311 return boolean_true_node
;
4313 /* If VR represents exactly one value equal to VAL, then return
4315 if (compare_values_warnv (vr
->min
, vr
->max
, strict_overflow_p
) == 0
4316 && compare_values_warnv (vr
->min
, val
, strict_overflow_p
) == 0)
4317 return boolean_false_node
;
4319 /* Otherwise, they may or may not be different. */
4322 else if (comp
== LT_EXPR
|| comp
== LE_EXPR
)
4326 /* If VR is to the left of VAL, return true. */
4327 tst
= compare_values_warnv (vr
->max
, val
, strict_overflow_p
);
4328 if ((comp
== LT_EXPR
&& tst
== -1)
4329 || (comp
== LE_EXPR
&& (tst
== -1 || tst
== 0)))
4330 return boolean_true_node
;
4332 /* If VR is to the right of VAL, return false. */
4333 tst
= compare_values_warnv (vr
->min
, val
, strict_overflow_p
);
4334 if ((comp
== LT_EXPR
&& (tst
== 0 || tst
== 1))
4335 || (comp
== LE_EXPR
&& tst
== 1))
4336 return boolean_false_node
;
4338 /* Otherwise, we don't know. */
4341 else if (comp
== GT_EXPR
|| comp
== GE_EXPR
)
4345 /* If VR is to the right of VAL, return true. */
4346 tst
= compare_values_warnv (vr
->min
, val
, strict_overflow_p
);
4347 if ((comp
== GT_EXPR
&& tst
== 1)
4348 || (comp
== GE_EXPR
&& (tst
== 0 || tst
== 1)))
4349 return boolean_true_node
;
4351 /* If VR is to the left of VAL, return false. */
4352 tst
= compare_values_warnv (vr
->max
, val
, strict_overflow_p
);
4353 if ((comp
== GT_EXPR
&& (tst
== -1 || tst
== 0))
4354 || (comp
== GE_EXPR
&& tst
== -1))
4355 return boolean_false_node
;
4357 /* Otherwise, we don't know. */
4365 /* Debugging dumps. */
4367 void dump_value_range (FILE *, const value_range
*);
4368 void debug_value_range (value_range
*);
4369 void dump_all_value_ranges (FILE *);
4370 void dump_vr_equiv (FILE *, bitmap
);
4371 void debug_vr_equiv (bitmap
);
4374 /* Dump value range VR to FILE. */
4377 dump_value_range (FILE *file
, const value_range
*vr
)
4380 fprintf (file
, "[]");
4381 else if (vr
->type
== VR_UNDEFINED
)
4382 fprintf (file
, "UNDEFINED");
4383 else if (vr
->type
== VR_RANGE
|| vr
->type
== VR_ANTI_RANGE
)
4385 tree type
= TREE_TYPE (vr
->min
);
4387 fprintf (file
, "%s[", (vr
->type
== VR_ANTI_RANGE
) ? "~" : "");
4389 if (INTEGRAL_TYPE_P (type
)
4390 && !TYPE_UNSIGNED (type
)
4391 && vrp_val_is_min (vr
->min
))
4392 fprintf (file
, "-INF");
4394 print_generic_expr (file
, vr
->min
);
4396 fprintf (file
, ", ");
4398 if (INTEGRAL_TYPE_P (type
)
4399 && vrp_val_is_max (vr
->max
))
4400 fprintf (file
, "+INF");
4402 print_generic_expr (file
, vr
->max
);
4404 fprintf (file
, "]");
4411 fprintf (file
, " EQUIVALENCES: { ");
4413 EXECUTE_IF_SET_IN_BITMAP (vr
->equiv
, 0, i
, bi
)
4415 print_generic_expr (file
, ssa_name (i
));
4416 fprintf (file
, " ");
4420 fprintf (file
, "} (%u elements)", c
);
4423 else if (vr
->type
== VR_VARYING
)
4424 fprintf (file
, "VARYING");
4426 fprintf (file
, "INVALID RANGE");
4430 /* Dump value range VR to stderr. */
4433 debug_value_range (value_range
*vr
)
4435 dump_value_range (stderr
, vr
);
4436 fprintf (stderr
, "\n");
4440 /* Dump value ranges of all SSA_NAMEs to FILE. */
4443 vr_values::dump_all_value_ranges (FILE *file
)
4447 for (i
= 0; i
< num_vr_values
; i
++)
4451 print_generic_expr (file
, ssa_name (i
));
4452 fprintf (file
, ": ");
4453 dump_value_range (file
, vr_value
[i
]);
4454 fprintf (file
, "\n");
4458 fprintf (file
, "\n");
4461 /* Given a COND_EXPR COND of the form 'V OP W', and an SSA name V,
4462 create a new SSA name N and return the assertion assignment
4463 'N = ASSERT_EXPR <V, V OP W>'. */
4466 build_assert_expr_for (tree cond
, tree v
)
4471 gcc_assert (TREE_CODE (v
) == SSA_NAME
4472 && COMPARISON_CLASS_P (cond
));
4474 a
= build2 (ASSERT_EXPR
, TREE_TYPE (v
), v
, cond
);
4475 assertion
= gimple_build_assign (NULL_TREE
, a
);
4477 /* The new ASSERT_EXPR, creates a new SSA name that replaces the
4478 operand of the ASSERT_EXPR. Create it so the new name and the old one
4479 are registered in the replacement table so that we can fix the SSA web
4480 after adding all the ASSERT_EXPRs. */
4481 tree new_def
= create_new_def_for (v
, assertion
, NULL
);
4482 /* Make sure we preserve abnormalness throughout an ASSERT_EXPR chain
4483 given we have to be able to fully propagate those out to re-create
4484 valid SSA when removing the asserts. */
4485 if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (v
))
4486 SSA_NAME_OCCURS_IN_ABNORMAL_PHI (new_def
) = 1;
4492 /* Return false if EXPR is a predicate expression involving floating
4496 fp_predicate (gimple
*stmt
)
4498 GIMPLE_CHECK (stmt
, GIMPLE_COND
);
4500 return FLOAT_TYPE_P (TREE_TYPE (gimple_cond_lhs (stmt
)));
4503 /* If the range of values taken by OP can be inferred after STMT executes,
4504 return the comparison code (COMP_CODE_P) and value (VAL_P) that
4505 describes the inferred range. Return true if a range could be
4509 infer_value_range (gimple
*stmt
, tree op
, tree_code
*comp_code_p
, tree
*val_p
)
4512 *comp_code_p
= ERROR_MARK
;
4514 /* Do not attempt to infer anything in names that flow through
4516 if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (op
))
4519 /* If STMT is the last statement of a basic block with no normal
4520 successors, there is no point inferring anything about any of its
4521 operands. We would not be able to find a proper insertion point
4522 for the assertion, anyway. */
4523 if (stmt_ends_bb_p (stmt
))
4528 FOR_EACH_EDGE (e
, ei
, gimple_bb (stmt
)->succs
)
4529 if (!(e
->flags
& (EDGE_ABNORMAL
|EDGE_EH
)))
4535 if (infer_nonnull_range (stmt
, op
))
4537 *val_p
= build_int_cst (TREE_TYPE (op
), 0);
4538 *comp_code_p
= NE_EXPR
;
4546 void dump_asserts_for (FILE *, tree
);
4547 void debug_asserts_for (tree
);
4548 void dump_all_asserts (FILE *);
4549 void debug_all_asserts (void);
4551 /* Dump all the registered assertions for NAME to FILE. */
4554 dump_asserts_for (FILE *file
, tree name
)
4558 fprintf (file
, "Assertions to be inserted for ");
4559 print_generic_expr (file
, name
);
4560 fprintf (file
, "\n");
4562 loc
= asserts_for
[SSA_NAME_VERSION (name
)];
4565 fprintf (file
, "\t");
4566 print_gimple_stmt (file
, gsi_stmt (loc
->si
), 0);
4567 fprintf (file
, "\n\tBB #%d", loc
->bb
->index
);
4570 fprintf (file
, "\n\tEDGE %d->%d", loc
->e
->src
->index
,
4571 loc
->e
->dest
->index
);
4572 dump_edge_info (file
, loc
->e
, dump_flags
, 0);
4574 fprintf (file
, "\n\tPREDICATE: ");
4575 print_generic_expr (file
, loc
->expr
);
4576 fprintf (file
, " %s ", get_tree_code_name (loc
->comp_code
));
4577 print_generic_expr (file
, loc
->val
);
4578 fprintf (file
, "\n\n");
4582 fprintf (file
, "\n");
4586 /* Dump all the registered assertions for NAME to stderr. */
4589 debug_asserts_for (tree name
)
4591 dump_asserts_for (stderr
, name
);
4595 /* Dump all the registered assertions for all the names to FILE. */
4598 dump_all_asserts (FILE *file
)
4603 fprintf (file
, "\nASSERT_EXPRs to be inserted\n\n");
4604 EXECUTE_IF_SET_IN_BITMAP (need_assert_for
, 0, i
, bi
)
4605 dump_asserts_for (file
, ssa_name (i
));
4606 fprintf (file
, "\n");
4610 /* Dump all the registered assertions for all the names to stderr. */
4613 debug_all_asserts (void)
4615 dump_all_asserts (stderr
);
4618 /* Push the assert info for NAME, EXPR, COMP_CODE and VAL to ASSERTS. */
4621 add_assert_info (vec
<assert_info
> &asserts
,
4622 tree name
, tree expr
, enum tree_code comp_code
, tree val
)
4625 info
.comp_code
= comp_code
;
4629 asserts
.safe_push (info
);
4632 /* If NAME doesn't have an ASSERT_EXPR registered for asserting
4633 'EXPR COMP_CODE VAL' at a location that dominates block BB or
4634 E->DEST, then register this location as a possible insertion point
4635 for ASSERT_EXPR <NAME, EXPR COMP_CODE VAL>.
4637 BB, E and SI provide the exact insertion point for the new
4638 ASSERT_EXPR. If BB is NULL, then the ASSERT_EXPR is to be inserted
4639 on edge E. Otherwise, if E is NULL, the ASSERT_EXPR is inserted on
4640 BB. If SI points to a COND_EXPR or a SWITCH_EXPR statement, then E
4641 must not be NULL. */
4644 register_new_assert_for (tree name
, tree expr
,
4645 enum tree_code comp_code
,
4649 gimple_stmt_iterator si
)
4651 assert_locus
*n
, *loc
, *last_loc
;
4652 basic_block dest_bb
;
4654 gcc_checking_assert (bb
== NULL
|| e
== NULL
);
4657 gcc_checking_assert (gimple_code (gsi_stmt (si
)) != GIMPLE_COND
4658 && gimple_code (gsi_stmt (si
)) != GIMPLE_SWITCH
);
4660 /* Never build an assert comparing against an integer constant with
4661 TREE_OVERFLOW set. This confuses our undefined overflow warning
4663 if (TREE_OVERFLOW_P (val
))
4664 val
= drop_tree_overflow (val
);
4666 /* The new assertion A will be inserted at BB or E. We need to
4667 determine if the new location is dominated by a previously
4668 registered location for A. If we are doing an edge insertion,
4669 assume that A will be inserted at E->DEST. Note that this is not
4672 If E is a critical edge, it will be split. But even if E is
4673 split, the new block will dominate the same set of blocks that
4676 The reverse, however, is not true, blocks dominated by E->DEST
4677 will not be dominated by the new block created to split E. So,
4678 if the insertion location is on a critical edge, we will not use
4679 the new location to move another assertion previously registered
4680 at a block dominated by E->DEST. */
4681 dest_bb
= (bb
) ? bb
: e
->dest
;
4683 /* If NAME already has an ASSERT_EXPR registered for COMP_CODE and
4684 VAL at a block dominating DEST_BB, then we don't need to insert a new
4685 one. Similarly, if the same assertion already exists at a block
4686 dominated by DEST_BB and the new location is not on a critical
4687 edge, then update the existing location for the assertion (i.e.,
4688 move the assertion up in the dominance tree).
4690 Note, this is implemented as a simple linked list because there
4691 should not be more than a handful of assertions registered per
4692 name. If this becomes a performance problem, a table hashed by
4693 COMP_CODE and VAL could be implemented. */
4694 loc
= asserts_for
[SSA_NAME_VERSION (name
)];
4698 if (loc
->comp_code
== comp_code
4700 || operand_equal_p (loc
->val
, val
, 0))
4701 && (loc
->expr
== expr
4702 || operand_equal_p (loc
->expr
, expr
, 0)))
4704 /* If E is not a critical edge and DEST_BB
4705 dominates the existing location for the assertion, move
4706 the assertion up in the dominance tree by updating its
4707 location information. */
4708 if ((e
== NULL
|| !EDGE_CRITICAL_P (e
))
4709 && dominated_by_p (CDI_DOMINATORS
, loc
->bb
, dest_bb
))
4718 /* Update the last node of the list and move to the next one. */
4723 /* If we didn't find an assertion already registered for
4724 NAME COMP_CODE VAL, add a new one at the end of the list of
4725 assertions associated with NAME. */
4726 n
= XNEW (struct assert_locus
);
4730 n
->comp_code
= comp_code
;
4738 asserts_for
[SSA_NAME_VERSION (name
)] = n
;
4740 bitmap_set_bit (need_assert_for
, SSA_NAME_VERSION (name
));
4743 /* (COND_OP0 COND_CODE COND_OP1) is a predicate which uses NAME.
4744 Extract a suitable test code and value and store them into *CODE_P and
4745 *VAL_P so the predicate is normalized to NAME *CODE_P *VAL_P.
4747 If no extraction was possible, return FALSE, otherwise return TRUE.
4749 If INVERT is true, then we invert the result stored into *CODE_P. */
4752 extract_code_and_val_from_cond_with_ops (tree name
, enum tree_code cond_code
,
4753 tree cond_op0
, tree cond_op1
,
4754 bool invert
, enum tree_code
*code_p
,
4757 enum tree_code comp_code
;
4760 /* Otherwise, we have a comparison of the form NAME COMP VAL
4761 or VAL COMP NAME. */
4762 if (name
== cond_op1
)
4764 /* If the predicate is of the form VAL COMP NAME, flip
4765 COMP around because we need to register NAME as the
4766 first operand in the predicate. */
4767 comp_code
= swap_tree_comparison (cond_code
);
4770 else if (name
== cond_op0
)
4772 /* The comparison is of the form NAME COMP VAL, so the
4773 comparison code remains unchanged. */
4774 comp_code
= cond_code
;
4780 /* Invert the comparison code as necessary. */
4782 comp_code
= invert_tree_comparison (comp_code
, 0);
4784 /* VRP only handles integral and pointer types. */
4785 if (! INTEGRAL_TYPE_P (TREE_TYPE (val
))
4786 && ! POINTER_TYPE_P (TREE_TYPE (val
)))
4789 /* Do not register always-false predicates.
4790 FIXME: this works around a limitation in fold() when dealing with
4791 enumerations. Given 'enum { N1, N2 } x;', fold will not
4792 fold 'if (x > N2)' to 'if (0)'. */
4793 if ((comp_code
== GT_EXPR
|| comp_code
== LT_EXPR
)
4794 && INTEGRAL_TYPE_P (TREE_TYPE (val
)))
4796 tree min
= TYPE_MIN_VALUE (TREE_TYPE (val
));
4797 tree max
= TYPE_MAX_VALUE (TREE_TYPE (val
));
4799 if (comp_code
== GT_EXPR
4801 || compare_values (val
, max
) == 0))
4804 if (comp_code
== LT_EXPR
4806 || compare_values (val
, min
) == 0))
4809 *code_p
= comp_code
;
4814 /* Find out smallest RES where RES > VAL && (RES & MASK) == RES, if any
4815 (otherwise return VAL). VAL and MASK must be zero-extended for
4816 precision PREC. If SGNBIT is non-zero, first xor VAL with SGNBIT
4817 (to transform signed values into unsigned) and at the end xor
4821 masked_increment (const wide_int
&val_in
, const wide_int
&mask
,
4822 const wide_int
&sgnbit
, unsigned int prec
)
4824 wide_int bit
= wi::one (prec
), res
;
4827 wide_int val
= val_in
^ sgnbit
;
4828 for (i
= 0; i
< prec
; i
++, bit
+= bit
)
4831 if ((res
& bit
) == 0)
4834 res
= wi::bit_and_not (val
+ bit
, res
);
4836 if (wi::gtu_p (res
, val
))
4837 return res
^ sgnbit
;
4839 return val
^ sgnbit
;
4842 /* Helper for overflow_comparison_p
4844 OP0 CODE OP1 is a comparison. Examine the comparison and potentially
4845 OP1's defining statement to see if it ultimately has the form
4846 OP0 CODE (OP0 PLUS INTEGER_CST)
4848 If so, return TRUE indicating this is an overflow test and store into
4849 *NEW_CST an updated constant that can be used in a narrowed range test.
4851 REVERSED indicates if the comparison was originally:
4855 This affects how we build the updated constant. */
4858 overflow_comparison_p_1 (enum tree_code code
, tree op0
, tree op1
,
4859 bool follow_assert_exprs
, bool reversed
, tree
*new_cst
)
4861 /* See if this is a relational operation between two SSA_NAMES with
4862 unsigned, overflow wrapping values. If so, check it more deeply. */
4863 if ((code
== LT_EXPR
|| code
== LE_EXPR
4864 || code
== GE_EXPR
|| code
== GT_EXPR
)
4865 && TREE_CODE (op0
) == SSA_NAME
4866 && TREE_CODE (op1
) == SSA_NAME
4867 && INTEGRAL_TYPE_P (TREE_TYPE (op0
))
4868 && TYPE_UNSIGNED (TREE_TYPE (op0
))
4869 && TYPE_OVERFLOW_WRAPS (TREE_TYPE (op0
)))
4871 gimple
*op1_def
= SSA_NAME_DEF_STMT (op1
);
4873 /* If requested, follow any ASSERT_EXPRs backwards for OP1. */
4874 if (follow_assert_exprs
)
4876 while (gimple_assign_single_p (op1_def
)
4877 && TREE_CODE (gimple_assign_rhs1 (op1_def
)) == ASSERT_EXPR
)
4879 op1
= TREE_OPERAND (gimple_assign_rhs1 (op1_def
), 0);
4880 if (TREE_CODE (op1
) != SSA_NAME
)
4882 op1_def
= SSA_NAME_DEF_STMT (op1
);
4886 /* Now look at the defining statement of OP1 to see if it adds
4887 or subtracts a nonzero constant from another operand. */
4889 && is_gimple_assign (op1_def
)
4890 && gimple_assign_rhs_code (op1_def
) == PLUS_EXPR
4891 && TREE_CODE (gimple_assign_rhs2 (op1_def
)) == INTEGER_CST
4892 && !integer_zerop (gimple_assign_rhs2 (op1_def
)))
4894 tree target
= gimple_assign_rhs1 (op1_def
);
4896 /* If requested, follow ASSERT_EXPRs backwards for op0 looking
4897 for one where TARGET appears on the RHS. */
4898 if (follow_assert_exprs
)
4900 /* Now see if that "other operand" is op0, following the chain
4901 of ASSERT_EXPRs if necessary. */
4902 gimple
*op0_def
= SSA_NAME_DEF_STMT (op0
);
4903 while (op0
!= target
4904 && gimple_assign_single_p (op0_def
)
4905 && TREE_CODE (gimple_assign_rhs1 (op0_def
)) == ASSERT_EXPR
)
4907 op0
= TREE_OPERAND (gimple_assign_rhs1 (op0_def
), 0);
4908 if (TREE_CODE (op0
) != SSA_NAME
)
4910 op0_def
= SSA_NAME_DEF_STMT (op0
);
4914 /* If we did not find our target SSA_NAME, then this is not
4915 an overflow test. */
4919 tree type
= TREE_TYPE (op0
);
4920 wide_int max
= wi::max_value (TYPE_PRECISION (type
), UNSIGNED
);
4921 tree inc
= gimple_assign_rhs2 (op1_def
);
4923 *new_cst
= wide_int_to_tree (type
, max
+ wi::to_wide (inc
));
4925 *new_cst
= wide_int_to_tree (type
, max
- wi::to_wide (inc
));
4932 /* OP0 CODE OP1 is a comparison. Examine the comparison and potentially
4933 OP1's defining statement to see if it ultimately has the form
4934 OP0 CODE (OP0 PLUS INTEGER_CST)
4936 If so, return TRUE indicating this is an overflow test and store into
4937 *NEW_CST an updated constant that can be used in a narrowed range test.
4939 These statements are left as-is in the IL to facilitate discovery of
4940 {ADD,SUB}_OVERFLOW sequences later in the optimizer pipeline. But
4941 the alternate range representation is often useful within VRP. */
4944 overflow_comparison_p (tree_code code
, tree name
, tree val
,
4945 bool use_equiv_p
, tree
*new_cst
)
4947 if (overflow_comparison_p_1 (code
, name
, val
, use_equiv_p
, false, new_cst
))
4949 return overflow_comparison_p_1 (swap_tree_comparison (code
), val
, name
,
4950 use_equiv_p
, true, new_cst
);
4954 /* Try to register an edge assertion for SSA name NAME on edge E for
4955 the condition COND contributing to the conditional jump pointed to by BSI.
4956 Invert the condition COND if INVERT is true. */
4959 register_edge_assert_for_2 (tree name
, edge e
,
4960 enum tree_code cond_code
,
4961 tree cond_op0
, tree cond_op1
, bool invert
,
4962 vec
<assert_info
> &asserts
)
4965 enum tree_code comp_code
;
4967 if (!extract_code_and_val_from_cond_with_ops (name
, cond_code
,
4970 invert
, &comp_code
, &val
))
4973 /* Queue the assert. */
4975 if (overflow_comparison_p (comp_code
, name
, val
, false, &x
))
4977 enum tree_code new_code
= ((comp_code
== GT_EXPR
|| comp_code
== GE_EXPR
)
4978 ? GT_EXPR
: LE_EXPR
);
4979 add_assert_info (asserts
, name
, name
, new_code
, x
);
4981 add_assert_info (asserts
, name
, name
, comp_code
, val
);
4983 /* In the case of NAME <= CST and NAME being defined as
4984 NAME = (unsigned) NAME2 + CST2 we can assert NAME2 >= -CST2
4985 and NAME2 <= CST - CST2. We can do the same for NAME > CST.
4986 This catches range and anti-range tests. */
4987 if ((comp_code
== LE_EXPR
4988 || comp_code
== GT_EXPR
)
4989 && TREE_CODE (val
) == INTEGER_CST
4990 && TYPE_UNSIGNED (TREE_TYPE (val
)))
4992 gimple
*def_stmt
= SSA_NAME_DEF_STMT (name
);
4993 tree cst2
= NULL_TREE
, name2
= NULL_TREE
, name3
= NULL_TREE
;
4995 /* Extract CST2 from the (optional) addition. */
4996 if (is_gimple_assign (def_stmt
)
4997 && gimple_assign_rhs_code (def_stmt
) == PLUS_EXPR
)
4999 name2
= gimple_assign_rhs1 (def_stmt
);
5000 cst2
= gimple_assign_rhs2 (def_stmt
);
5001 if (TREE_CODE (name2
) == SSA_NAME
5002 && TREE_CODE (cst2
) == INTEGER_CST
)
5003 def_stmt
= SSA_NAME_DEF_STMT (name2
);
5006 /* Extract NAME2 from the (optional) sign-changing cast. */
5007 if (gimple_assign_cast_p (def_stmt
))
5009 if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt
))
5010 && ! TYPE_UNSIGNED (TREE_TYPE (gimple_assign_rhs1 (def_stmt
)))
5011 && (TYPE_PRECISION (gimple_expr_type (def_stmt
))
5012 == TYPE_PRECISION (TREE_TYPE (gimple_assign_rhs1 (def_stmt
)))))
5013 name3
= gimple_assign_rhs1 (def_stmt
);
5016 /* If name3 is used later, create an ASSERT_EXPR for it. */
5017 if (name3
!= NULL_TREE
5018 && TREE_CODE (name3
) == SSA_NAME
5019 && (cst2
== NULL_TREE
5020 || TREE_CODE (cst2
) == INTEGER_CST
)
5021 && INTEGRAL_TYPE_P (TREE_TYPE (name3
)))
5025 /* Build an expression for the range test. */
5026 tmp
= build1 (NOP_EXPR
, TREE_TYPE (name
), name3
);
5027 if (cst2
!= NULL_TREE
)
5028 tmp
= build2 (PLUS_EXPR
, TREE_TYPE (name
), tmp
, cst2
);
5032 fprintf (dump_file
, "Adding assert for ");
5033 print_generic_expr (dump_file
, name3
);
5034 fprintf (dump_file
, " from ");
5035 print_generic_expr (dump_file
, tmp
);
5036 fprintf (dump_file
, "\n");
5039 add_assert_info (asserts
, name3
, tmp
, comp_code
, val
);
5042 /* If name2 is used later, create an ASSERT_EXPR for it. */
5043 if (name2
!= NULL_TREE
5044 && TREE_CODE (name2
) == SSA_NAME
5045 && TREE_CODE (cst2
) == INTEGER_CST
5046 && INTEGRAL_TYPE_P (TREE_TYPE (name2
)))
5050 /* Build an expression for the range test. */
5052 if (TREE_TYPE (name
) != TREE_TYPE (name2
))
5053 tmp
= build1 (NOP_EXPR
, TREE_TYPE (name
), tmp
);
5054 if (cst2
!= NULL_TREE
)
5055 tmp
= build2 (PLUS_EXPR
, TREE_TYPE (name
), tmp
, cst2
);
5059 fprintf (dump_file
, "Adding assert for ");
5060 print_generic_expr (dump_file
, name2
);
5061 fprintf (dump_file
, " from ");
5062 print_generic_expr (dump_file
, tmp
);
5063 fprintf (dump_file
, "\n");
5066 add_assert_info (asserts
, name2
, tmp
, comp_code
, val
);
5070 /* In the case of post-in/decrement tests like if (i++) ... and uses
5071 of the in/decremented value on the edge the extra name we want to
5072 assert for is not on the def chain of the name compared. Instead
5073 it is in the set of use stmts.
5074 Similar cases happen for conversions that were simplified through
5075 fold_{sign_changed,widened}_comparison. */
5076 if ((comp_code
== NE_EXPR
5077 || comp_code
== EQ_EXPR
)
5078 && TREE_CODE (val
) == INTEGER_CST
)
5080 imm_use_iterator ui
;
5082 FOR_EACH_IMM_USE_STMT (use_stmt
, ui
, name
)
5084 if (!is_gimple_assign (use_stmt
))
5087 /* Cut off to use-stmts that are dominating the predecessor. */
5088 if (!dominated_by_p (CDI_DOMINATORS
, e
->src
, gimple_bb (use_stmt
)))
5091 tree name2
= gimple_assign_lhs (use_stmt
);
5092 if (TREE_CODE (name2
) != SSA_NAME
)
5095 enum tree_code code
= gimple_assign_rhs_code (use_stmt
);
5097 if (code
== PLUS_EXPR
5098 || code
== MINUS_EXPR
)
5100 cst
= gimple_assign_rhs2 (use_stmt
);
5101 if (TREE_CODE (cst
) != INTEGER_CST
)
5103 cst
= int_const_binop (code
, val
, cst
);
5105 else if (CONVERT_EXPR_CODE_P (code
))
5107 /* For truncating conversions we cannot record
5109 if (comp_code
== NE_EXPR
5110 && (TYPE_PRECISION (TREE_TYPE (name2
))
5111 < TYPE_PRECISION (TREE_TYPE (name
))))
5113 cst
= fold_convert (TREE_TYPE (name2
), val
);
5118 if (TREE_OVERFLOW_P (cst
))
5119 cst
= drop_tree_overflow (cst
);
5120 add_assert_info (asserts
, name2
, name2
, comp_code
, cst
);
5124 if (TREE_CODE_CLASS (comp_code
) == tcc_comparison
5125 && TREE_CODE (val
) == INTEGER_CST
)
5127 gimple
*def_stmt
= SSA_NAME_DEF_STMT (name
);
5128 tree name2
= NULL_TREE
, names
[2], cst2
= NULL_TREE
;
5129 tree val2
= NULL_TREE
;
5130 unsigned int prec
= TYPE_PRECISION (TREE_TYPE (val
));
5131 wide_int mask
= wi::zero (prec
);
5132 unsigned int nprec
= prec
;
5133 enum tree_code rhs_code
= ERROR_MARK
;
5135 if (is_gimple_assign (def_stmt
))
5136 rhs_code
= gimple_assign_rhs_code (def_stmt
);
5138 /* In the case of NAME != CST1 where NAME = A +- CST2 we can
5139 assert that A != CST1 -+ CST2. */
5140 if ((comp_code
== EQ_EXPR
|| comp_code
== NE_EXPR
)
5141 && (rhs_code
== PLUS_EXPR
|| rhs_code
== MINUS_EXPR
))
5143 tree op0
= gimple_assign_rhs1 (def_stmt
);
5144 tree op1
= gimple_assign_rhs2 (def_stmt
);
5145 if (TREE_CODE (op0
) == SSA_NAME
5146 && TREE_CODE (op1
) == INTEGER_CST
)
5148 enum tree_code reverse_op
= (rhs_code
== PLUS_EXPR
5149 ? MINUS_EXPR
: PLUS_EXPR
);
5150 op1
= int_const_binop (reverse_op
, val
, op1
);
5151 if (TREE_OVERFLOW (op1
))
5152 op1
= drop_tree_overflow (op1
);
5153 add_assert_info (asserts
, op0
, op0
, comp_code
, op1
);
5157 /* Add asserts for NAME cmp CST and NAME being defined
5158 as NAME = (int) NAME2. */
5159 if (!TYPE_UNSIGNED (TREE_TYPE (val
))
5160 && (comp_code
== LE_EXPR
|| comp_code
== LT_EXPR
5161 || comp_code
== GT_EXPR
|| comp_code
== GE_EXPR
)
5162 && gimple_assign_cast_p (def_stmt
))
5164 name2
= gimple_assign_rhs1 (def_stmt
);
5165 if (CONVERT_EXPR_CODE_P (rhs_code
)
5166 && INTEGRAL_TYPE_P (TREE_TYPE (name2
))
5167 && TYPE_UNSIGNED (TREE_TYPE (name2
))
5168 && prec
== TYPE_PRECISION (TREE_TYPE (name2
))
5169 && (comp_code
== LE_EXPR
|| comp_code
== GT_EXPR
5170 || !tree_int_cst_equal (val
,
5171 TYPE_MIN_VALUE (TREE_TYPE (val
)))))
5174 enum tree_code new_comp_code
= comp_code
;
5176 cst
= fold_convert (TREE_TYPE (name2
),
5177 TYPE_MIN_VALUE (TREE_TYPE (val
)));
5178 /* Build an expression for the range test. */
5179 tmp
= build2 (PLUS_EXPR
, TREE_TYPE (name2
), name2
, cst
);
5180 cst
= fold_build2 (PLUS_EXPR
, TREE_TYPE (name2
), cst
,
5181 fold_convert (TREE_TYPE (name2
), val
));
5182 if (comp_code
== LT_EXPR
|| comp_code
== GE_EXPR
)
5184 new_comp_code
= comp_code
== LT_EXPR
? LE_EXPR
: GT_EXPR
;
5185 cst
= fold_build2 (MINUS_EXPR
, TREE_TYPE (name2
), cst
,
5186 build_int_cst (TREE_TYPE (name2
), 1));
5191 fprintf (dump_file
, "Adding assert for ");
5192 print_generic_expr (dump_file
, name2
);
5193 fprintf (dump_file
, " from ");
5194 print_generic_expr (dump_file
, tmp
);
5195 fprintf (dump_file
, "\n");
5198 add_assert_info (asserts
, name2
, tmp
, new_comp_code
, cst
);
5202 /* Add asserts for NAME cmp CST and NAME being defined as
5203 NAME = NAME2 >> CST2.
5205 Extract CST2 from the right shift. */
5206 if (rhs_code
== RSHIFT_EXPR
)
5208 name2
= gimple_assign_rhs1 (def_stmt
);
5209 cst2
= gimple_assign_rhs2 (def_stmt
);
5210 if (TREE_CODE (name2
) == SSA_NAME
5211 && tree_fits_uhwi_p (cst2
)
5212 && INTEGRAL_TYPE_P (TREE_TYPE (name2
))
5213 && IN_RANGE (tree_to_uhwi (cst2
), 1, prec
- 1)
5214 && type_has_mode_precision_p (TREE_TYPE (val
)))
5216 mask
= wi::mask (tree_to_uhwi (cst2
), false, prec
);
5217 val2
= fold_binary (LSHIFT_EXPR
, TREE_TYPE (val
), val
, cst2
);
5220 if (val2
!= NULL_TREE
5221 && TREE_CODE (val2
) == INTEGER_CST
5222 && simple_cst_equal (fold_build2 (RSHIFT_EXPR
,
5226 enum tree_code new_comp_code
= comp_code
;
5230 if (comp_code
== EQ_EXPR
|| comp_code
== NE_EXPR
)
5232 if (!TYPE_UNSIGNED (TREE_TYPE (val
)))
5234 tree type
= build_nonstandard_integer_type (prec
, 1);
5235 tmp
= build1 (NOP_EXPR
, type
, name2
);
5236 val2
= fold_convert (type
, val2
);
5238 tmp
= fold_build2 (MINUS_EXPR
, TREE_TYPE (tmp
), tmp
, val2
);
5239 new_val
= wide_int_to_tree (TREE_TYPE (tmp
), mask
);
5240 new_comp_code
= comp_code
== EQ_EXPR
? LE_EXPR
: GT_EXPR
;
5242 else if (comp_code
== LT_EXPR
|| comp_code
== GE_EXPR
)
5245 = wi::min_value (prec
, TYPE_SIGN (TREE_TYPE (val
)));
5247 if (minval
== wi::to_wide (new_val
))
5248 new_val
= NULL_TREE
;
5253 = wi::max_value (prec
, TYPE_SIGN (TREE_TYPE (val
)));
5254 mask
|= wi::to_wide (val2
);
5255 if (wi::eq_p (mask
, maxval
))
5256 new_val
= NULL_TREE
;
5258 new_val
= wide_int_to_tree (TREE_TYPE (val2
), mask
);
5265 fprintf (dump_file
, "Adding assert for ");
5266 print_generic_expr (dump_file
, name2
);
5267 fprintf (dump_file
, " from ");
5268 print_generic_expr (dump_file
, tmp
);
5269 fprintf (dump_file
, "\n");
5272 add_assert_info (asserts
, name2
, tmp
, new_comp_code
, new_val
);
5276 /* Add asserts for NAME cmp CST and NAME being defined as
5277 NAME = NAME2 & CST2.
5279 Extract CST2 from the and.
5282 NAME = (unsigned) NAME2;
5283 casts where NAME's type is unsigned and has smaller precision
5284 than NAME2's type as if it was NAME = NAME2 & MASK. */
5285 names
[0] = NULL_TREE
;
5286 names
[1] = NULL_TREE
;
5288 if (rhs_code
== BIT_AND_EXPR
5289 || (CONVERT_EXPR_CODE_P (rhs_code
)
5290 && INTEGRAL_TYPE_P (TREE_TYPE (val
))
5291 && TYPE_UNSIGNED (TREE_TYPE (val
))
5292 && TYPE_PRECISION (TREE_TYPE (gimple_assign_rhs1 (def_stmt
)))
5295 name2
= gimple_assign_rhs1 (def_stmt
);
5296 if (rhs_code
== BIT_AND_EXPR
)
5297 cst2
= gimple_assign_rhs2 (def_stmt
);
5300 cst2
= TYPE_MAX_VALUE (TREE_TYPE (val
));
5301 nprec
= TYPE_PRECISION (TREE_TYPE (name2
));
5303 if (TREE_CODE (name2
) == SSA_NAME
5304 && INTEGRAL_TYPE_P (TREE_TYPE (name2
))
5305 && TREE_CODE (cst2
) == INTEGER_CST
5306 && !integer_zerop (cst2
)
5308 || TYPE_UNSIGNED (TREE_TYPE (val
))))
5310 gimple
*def_stmt2
= SSA_NAME_DEF_STMT (name2
);
5311 if (gimple_assign_cast_p (def_stmt2
))
5313 names
[1] = gimple_assign_rhs1 (def_stmt2
);
5314 if (!CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt2
))
5315 || !INTEGRAL_TYPE_P (TREE_TYPE (names
[1]))
5316 || (TYPE_PRECISION (TREE_TYPE (name2
))
5317 != TYPE_PRECISION (TREE_TYPE (names
[1]))))
5318 names
[1] = NULL_TREE
;
5323 if (names
[0] || names
[1])
5325 wide_int minv
, maxv
, valv
, cst2v
;
5326 wide_int tem
, sgnbit
;
5327 bool valid_p
= false, valn
, cst2n
;
5328 enum tree_code ccode
= comp_code
;
5330 valv
= wide_int::from (wi::to_wide (val
), nprec
, UNSIGNED
);
5331 cst2v
= wide_int::from (wi::to_wide (cst2
), nprec
, UNSIGNED
);
5332 valn
= wi::neg_p (valv
, TYPE_SIGN (TREE_TYPE (val
)));
5333 cst2n
= wi::neg_p (cst2v
, TYPE_SIGN (TREE_TYPE (val
)));
5334 /* If CST2 doesn't have most significant bit set,
5335 but VAL is negative, we have comparison like
5336 if ((x & 0x123) > -4) (always true). Just give up. */
5340 sgnbit
= wi::set_bit_in_zero (nprec
- 1, nprec
);
5342 sgnbit
= wi::zero (nprec
);
5343 minv
= valv
& cst2v
;
5347 /* Minimum unsigned value for equality is VAL & CST2
5348 (should be equal to VAL, otherwise we probably should
5349 have folded the comparison into false) and
5350 maximum unsigned value is VAL | ~CST2. */
5351 maxv
= valv
| ~cst2v
;
5356 tem
= valv
| ~cst2v
;
5357 /* If VAL is 0, handle (X & CST2) != 0 as (X & CST2) > 0U. */
5361 sgnbit
= wi::zero (nprec
);
5364 /* If (VAL | ~CST2) is all ones, handle it as
5365 (X & CST2) < VAL. */
5370 sgnbit
= wi::zero (nprec
);
5373 if (!cst2n
&& wi::neg_p (cst2v
))
5374 sgnbit
= wi::set_bit_in_zero (nprec
- 1, nprec
);
5383 if (tem
== wi::mask (nprec
- 1, false, nprec
))
5389 sgnbit
= wi::zero (nprec
);
5394 /* Minimum unsigned value for >= if (VAL & CST2) == VAL
5395 is VAL and maximum unsigned value is ~0. For signed
5396 comparison, if CST2 doesn't have most significant bit
5397 set, handle it similarly. If CST2 has MSB set,
5398 the minimum is the same, and maximum is ~0U/2. */
5401 /* If (VAL & CST2) != VAL, X & CST2 can't be equal to
5403 minv
= masked_increment (valv
, cst2v
, sgnbit
, nprec
);
5407 maxv
= wi::mask (nprec
- (cst2n
? 1 : 0), false, nprec
);
5413 /* Find out smallest MINV where MINV > VAL
5414 && (MINV & CST2) == MINV, if any. If VAL is signed and
5415 CST2 has MSB set, compute it biased by 1 << (nprec - 1). */
5416 minv
= masked_increment (valv
, cst2v
, sgnbit
, nprec
);
5419 maxv
= wi::mask (nprec
- (cst2n
? 1 : 0), false, nprec
);
5424 /* Minimum unsigned value for <= is 0 and maximum
5425 unsigned value is VAL | ~CST2 if (VAL & CST2) == VAL.
5426 Otherwise, find smallest VAL2 where VAL2 > VAL
5427 && (VAL2 & CST2) == VAL2 and use (VAL2 - 1) | ~CST2
5429 For signed comparison, if CST2 doesn't have most
5430 significant bit set, handle it similarly. If CST2 has
5431 MSB set, the maximum is the same and minimum is INT_MIN. */
5436 maxv
= masked_increment (valv
, cst2v
, sgnbit
, nprec
);
5448 /* Minimum unsigned value for < is 0 and maximum
5449 unsigned value is (VAL-1) | ~CST2 if (VAL & CST2) == VAL.
5450 Otherwise, find smallest VAL2 where VAL2 > VAL
5451 && (VAL2 & CST2) == VAL2 and use (VAL2 - 1) | ~CST2
5453 For signed comparison, if CST2 doesn't have most
5454 significant bit set, handle it similarly. If CST2 has
5455 MSB set, the maximum is the same and minimum is INT_MIN. */
5464 maxv
= masked_increment (valv
, cst2v
, sgnbit
, nprec
);
5478 && (maxv
- minv
) != -1)
5480 tree tmp
, new_val
, type
;
5483 for (i
= 0; i
< 2; i
++)
5486 wide_int maxv2
= maxv
;
5488 type
= TREE_TYPE (names
[i
]);
5489 if (!TYPE_UNSIGNED (type
))
5491 type
= build_nonstandard_integer_type (nprec
, 1);
5492 tmp
= build1 (NOP_EXPR
, type
, names
[i
]);
5496 tmp
= build2 (PLUS_EXPR
, type
, tmp
,
5497 wide_int_to_tree (type
, -minv
));
5498 maxv2
= maxv
- minv
;
5500 new_val
= wide_int_to_tree (type
, maxv2
);
5504 fprintf (dump_file
, "Adding assert for ");
5505 print_generic_expr (dump_file
, names
[i
]);
5506 fprintf (dump_file
, " from ");
5507 print_generic_expr (dump_file
, tmp
);
5508 fprintf (dump_file
, "\n");
5511 add_assert_info (asserts
, names
[i
], tmp
, LE_EXPR
, new_val
);
5518 /* OP is an operand of a truth value expression which is known to have
5519 a particular value. Register any asserts for OP and for any
5520 operands in OP's defining statement.
5522 If CODE is EQ_EXPR, then we want to register OP is zero (false),
5523 if CODE is NE_EXPR, then we want to register OP is nonzero (true). */
5526 register_edge_assert_for_1 (tree op
, enum tree_code code
,
5527 edge e
, vec
<assert_info
> &asserts
)
5531 enum tree_code rhs_code
;
5533 /* We only care about SSA_NAMEs. */
5534 if (TREE_CODE (op
) != SSA_NAME
)
5537 /* We know that OP will have a zero or nonzero value. */
5538 val
= build_int_cst (TREE_TYPE (op
), 0);
5539 add_assert_info (asserts
, op
, op
, code
, val
);
5541 /* Now look at how OP is set. If it's set from a comparison,
5542 a truth operation or some bit operations, then we may be able
5543 to register information about the operands of that assignment. */
5544 op_def
= SSA_NAME_DEF_STMT (op
);
5545 if (gimple_code (op_def
) != GIMPLE_ASSIGN
)
5548 rhs_code
= gimple_assign_rhs_code (op_def
);
5550 if (TREE_CODE_CLASS (rhs_code
) == tcc_comparison
)
5552 bool invert
= (code
== EQ_EXPR
? true : false);
5553 tree op0
= gimple_assign_rhs1 (op_def
);
5554 tree op1
= gimple_assign_rhs2 (op_def
);
5556 if (TREE_CODE (op0
) == SSA_NAME
)
5557 register_edge_assert_for_2 (op0
, e
, rhs_code
, op0
, op1
, invert
, asserts
);
5558 if (TREE_CODE (op1
) == SSA_NAME
)
5559 register_edge_assert_for_2 (op1
, e
, rhs_code
, op0
, op1
, invert
, asserts
);
5561 else if ((code
== NE_EXPR
5562 && gimple_assign_rhs_code (op_def
) == BIT_AND_EXPR
)
5564 && gimple_assign_rhs_code (op_def
) == BIT_IOR_EXPR
))
5566 /* Recurse on each operand. */
5567 tree op0
= gimple_assign_rhs1 (op_def
);
5568 tree op1
= gimple_assign_rhs2 (op_def
);
5569 if (TREE_CODE (op0
) == SSA_NAME
5570 && has_single_use (op0
))
5571 register_edge_assert_for_1 (op0
, code
, e
, asserts
);
5572 if (TREE_CODE (op1
) == SSA_NAME
5573 && has_single_use (op1
))
5574 register_edge_assert_for_1 (op1
, code
, e
, asserts
);
5576 else if (gimple_assign_rhs_code (op_def
) == BIT_NOT_EXPR
5577 && TYPE_PRECISION (TREE_TYPE (gimple_assign_lhs (op_def
))) == 1)
5579 /* Recurse, flipping CODE. */
5580 code
= invert_tree_comparison (code
, false);
5581 register_edge_assert_for_1 (gimple_assign_rhs1 (op_def
), code
, e
, asserts
);
5583 else if (gimple_assign_rhs_code (op_def
) == SSA_NAME
)
5585 /* Recurse through the copy. */
5586 register_edge_assert_for_1 (gimple_assign_rhs1 (op_def
), code
, e
, asserts
);
5588 else if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (op_def
)))
5590 /* Recurse through the type conversion, unless it is a narrowing
5591 conversion or conversion from non-integral type. */
5592 tree rhs
= gimple_assign_rhs1 (op_def
);
5593 if (INTEGRAL_TYPE_P (TREE_TYPE (rhs
))
5594 && (TYPE_PRECISION (TREE_TYPE (rhs
))
5595 <= TYPE_PRECISION (TREE_TYPE (op
))))
5596 register_edge_assert_for_1 (rhs
, code
, e
, asserts
);
5600 /* Check if comparison
5601 NAME COND_OP INTEGER_CST
5603 (X & 11...100..0) COND_OP XX...X00...0
5604 Such comparison can yield assertions like
5607 in case of COND_OP being NE_EXPR or
5610 in case of EQ_EXPR. */
5613 is_masked_range_test (tree name
, tree valt
, enum tree_code cond_code
,
5614 tree
*new_name
, tree
*low
, enum tree_code
*low_code
,
5615 tree
*high
, enum tree_code
*high_code
)
5617 gimple
*def_stmt
= SSA_NAME_DEF_STMT (name
);
5619 if (!is_gimple_assign (def_stmt
)
5620 || gimple_assign_rhs_code (def_stmt
) != BIT_AND_EXPR
)
5623 tree t
= gimple_assign_rhs1 (def_stmt
);
5624 tree maskt
= gimple_assign_rhs2 (def_stmt
);
5625 if (TREE_CODE (t
) != SSA_NAME
|| TREE_CODE (maskt
) != INTEGER_CST
)
5628 wi::tree_to_wide_ref mask
= wi::to_wide (maskt
);
5629 wide_int inv_mask
= ~mask
;
5630 /* Assume VALT is INTEGER_CST. */
5631 wi::tree_to_wide_ref val
= wi::to_wide (valt
);
5633 if ((inv_mask
& (inv_mask
+ 1)) != 0
5634 || (val
& mask
) != val
)
5637 bool is_range
= cond_code
== EQ_EXPR
;
5639 tree type
= TREE_TYPE (t
);
5640 wide_int min
= wi::min_value (type
),
5641 max
= wi::max_value (type
);
5645 *low_code
= val
== min
? ERROR_MARK
: GE_EXPR
;
5646 *high_code
= val
== max
? ERROR_MARK
: LE_EXPR
;
5650 /* We can still generate assertion if one of alternatives
5651 is known to always be false. */
5654 *low_code
= (enum tree_code
) 0;
5655 *high_code
= GT_EXPR
;
5657 else if ((val
| inv_mask
) == max
)
5659 *low_code
= LT_EXPR
;
5660 *high_code
= (enum tree_code
) 0;
5667 *low
= wide_int_to_tree (type
, val
);
5668 *high
= wide_int_to_tree (type
, val
| inv_mask
);
5670 if (wi::neg_p (val
, TYPE_SIGN (type
)))
5671 std::swap (*low
, *high
);
5676 /* Try to register an edge assertion for SSA name NAME on edge E for
5677 the condition COND contributing to the conditional jump pointed to by
5681 register_edge_assert_for (tree name
, edge e
,
5682 enum tree_code cond_code
, tree cond_op0
,
5683 tree cond_op1
, vec
<assert_info
> &asserts
)
5686 enum tree_code comp_code
;
5687 bool is_else_edge
= (e
->flags
& EDGE_FALSE_VALUE
) != 0;
5689 /* Do not attempt to infer anything in names that flow through
5691 if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name
))
5694 if (!extract_code_and_val_from_cond_with_ops (name
, cond_code
,
5700 /* Register ASSERT_EXPRs for name. */
5701 register_edge_assert_for_2 (name
, e
, cond_code
, cond_op0
,
5702 cond_op1
, is_else_edge
, asserts
);
5705 /* If COND is effectively an equality test of an SSA_NAME against
5706 the value zero or one, then we may be able to assert values
5707 for SSA_NAMEs which flow into COND. */
5709 /* In the case of NAME == 1 or NAME != 0, for BIT_AND_EXPR defining
5710 statement of NAME we can assert both operands of the BIT_AND_EXPR
5711 have nonzero value. */
5712 if (((comp_code
== EQ_EXPR
&& integer_onep (val
))
5713 || (comp_code
== NE_EXPR
&& integer_zerop (val
))))
5715 gimple
*def_stmt
= SSA_NAME_DEF_STMT (name
);
5717 if (is_gimple_assign (def_stmt
)
5718 && gimple_assign_rhs_code (def_stmt
) == BIT_AND_EXPR
)
5720 tree op0
= gimple_assign_rhs1 (def_stmt
);
5721 tree op1
= gimple_assign_rhs2 (def_stmt
);
5722 register_edge_assert_for_1 (op0
, NE_EXPR
, e
, asserts
);
5723 register_edge_assert_for_1 (op1
, NE_EXPR
, e
, asserts
);
5727 /* In the case of NAME == 0 or NAME != 1, for BIT_IOR_EXPR defining
5728 statement of NAME we can assert both operands of the BIT_IOR_EXPR
5730 if (((comp_code
== EQ_EXPR
&& integer_zerop (val
))
5731 || (comp_code
== NE_EXPR
&& integer_onep (val
))))
5733 gimple
*def_stmt
= SSA_NAME_DEF_STMT (name
);
5735 /* For BIT_IOR_EXPR only if NAME == 0 both operands have
5736 necessarily zero value, or if type-precision is one. */
5737 if (is_gimple_assign (def_stmt
)
5738 && (gimple_assign_rhs_code (def_stmt
) == BIT_IOR_EXPR
5739 && (TYPE_PRECISION (TREE_TYPE (name
)) == 1
5740 || comp_code
== EQ_EXPR
)))
5742 tree op0
= gimple_assign_rhs1 (def_stmt
);
5743 tree op1
= gimple_assign_rhs2 (def_stmt
);
5744 register_edge_assert_for_1 (op0
, EQ_EXPR
, e
, asserts
);
5745 register_edge_assert_for_1 (op1
, EQ_EXPR
, e
, asserts
);
5749 /* Sometimes we can infer ranges from (NAME & MASK) == VALUE. */
5750 if ((comp_code
== EQ_EXPR
|| comp_code
== NE_EXPR
)
5751 && TREE_CODE (val
) == INTEGER_CST
)
5753 enum tree_code low_code
, high_code
;
5755 if (is_masked_range_test (name
, val
, comp_code
, &name
, &low
,
5756 &low_code
, &high
, &high_code
))
5758 if (low_code
!= ERROR_MARK
)
5759 register_edge_assert_for_2 (name
, e
, low_code
, name
,
5760 low
, /*invert*/false, asserts
);
5761 if (high_code
!= ERROR_MARK
)
5762 register_edge_assert_for_2 (name
, e
, high_code
, name
,
5763 high
, /*invert*/false, asserts
);
5768 /* Finish found ASSERTS for E and register them at GSI. */
5771 finish_register_edge_assert_for (edge e
, gimple_stmt_iterator gsi
,
5772 vec
<assert_info
> &asserts
)
5774 for (unsigned i
= 0; i
< asserts
.length (); ++i
)
5775 /* Only register an ASSERT_EXPR if NAME was found in the sub-graph
5776 reachable from E. */
5777 if (live_on_edge (e
, asserts
[i
].name
))
5778 register_new_assert_for (asserts
[i
].name
, asserts
[i
].expr
,
5779 asserts
[i
].comp_code
, asserts
[i
].val
,
5785 /* Determine whether the outgoing edges of BB should receive an
5786 ASSERT_EXPR for each of the operands of BB's LAST statement.
5787 The last statement of BB must be a COND_EXPR.
5789 If any of the sub-graphs rooted at BB have an interesting use of
5790 the predicate operands, an assert location node is added to the
5791 list of assertions for the corresponding operands. */
5794 find_conditional_asserts (basic_block bb
, gcond
*last
)
5796 gimple_stmt_iterator bsi
;
5802 bsi
= gsi_for_stmt (last
);
5804 /* Look for uses of the operands in each of the sub-graphs
5805 rooted at BB. We need to check each of the outgoing edges
5806 separately, so that we know what kind of ASSERT_EXPR to
5808 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
5813 /* Register the necessary assertions for each operand in the
5814 conditional predicate. */
5815 auto_vec
<assert_info
, 8> asserts
;
5816 FOR_EACH_SSA_TREE_OPERAND (op
, last
, iter
, SSA_OP_USE
)
5817 register_edge_assert_for (op
, e
,
5818 gimple_cond_code (last
),
5819 gimple_cond_lhs (last
),
5820 gimple_cond_rhs (last
), asserts
);
5821 finish_register_edge_assert_for (e
, bsi
, asserts
);
5831 /* Compare two case labels sorting first by the destination bb index
5832 and then by the case value. */
5835 compare_case_labels (const void *p1
, const void *p2
)
5837 const struct case_info
*ci1
= (const struct case_info
*) p1
;
5838 const struct case_info
*ci2
= (const struct case_info
*) p2
;
5839 int idx1
= ci1
->bb
->index
;
5840 int idx2
= ci2
->bb
->index
;
5844 else if (idx1
== idx2
)
5846 /* Make sure the default label is first in a group. */
5847 if (!CASE_LOW (ci1
->expr
))
5849 else if (!CASE_LOW (ci2
->expr
))
5852 return tree_int_cst_compare (CASE_LOW (ci1
->expr
),
5853 CASE_LOW (ci2
->expr
));
5859 /* Determine whether the outgoing edges of BB should receive an
5860 ASSERT_EXPR for each of the operands of BB's LAST statement.
5861 The last statement of BB must be a SWITCH_EXPR.
5863 If any of the sub-graphs rooted at BB have an interesting use of
5864 the predicate operands, an assert location node is added to the
5865 list of assertions for the corresponding operands. */
5868 find_switch_asserts (basic_block bb
, gswitch
*last
)
5870 gimple_stmt_iterator bsi
;
5873 struct case_info
*ci
;
5874 size_t n
= gimple_switch_num_labels (last
);
5875 #if GCC_VERSION >= 4000
5878 /* Work around GCC 3.4 bug (PR 37086). */
5879 volatile unsigned int idx
;
5882 bsi
= gsi_for_stmt (last
);
5883 op
= gimple_switch_index (last
);
5884 if (TREE_CODE (op
) != SSA_NAME
)
5887 /* Build a vector of case labels sorted by destination label. */
5888 ci
= XNEWVEC (struct case_info
, n
);
5889 for (idx
= 0; idx
< n
; ++idx
)
5891 ci
[idx
].expr
= gimple_switch_label (last
, idx
);
5892 ci
[idx
].bb
= label_to_block (CASE_LABEL (ci
[idx
].expr
));
5894 edge default_edge
= find_edge (bb
, ci
[0].bb
);
5895 qsort (ci
, n
, sizeof (struct case_info
), compare_case_labels
);
5897 for (idx
= 0; idx
< n
; ++idx
)
5900 tree cl
= ci
[idx
].expr
;
5901 basic_block cbb
= ci
[idx
].bb
;
5903 min
= CASE_LOW (cl
);
5904 max
= CASE_HIGH (cl
);
5906 /* If there are multiple case labels with the same destination
5907 we need to combine them to a single value range for the edge. */
5908 if (idx
+ 1 < n
&& cbb
== ci
[idx
+ 1].bb
)
5910 /* Skip labels until the last of the group. */
5913 } while (idx
< n
&& cbb
== ci
[idx
].bb
);
5916 /* Pick up the maximum of the case label range. */
5917 if (CASE_HIGH (ci
[idx
].expr
))
5918 max
= CASE_HIGH (ci
[idx
].expr
);
5920 max
= CASE_LOW (ci
[idx
].expr
);
5923 /* Can't extract a useful assertion out of a range that includes the
5925 if (min
== NULL_TREE
)
5928 /* Find the edge to register the assert expr on. */
5929 e
= find_edge (bb
, cbb
);
5931 /* Register the necessary assertions for the operand in the
5933 auto_vec
<assert_info
, 8> asserts
;
5934 register_edge_assert_for (op
, e
,
5935 max
? GE_EXPR
: EQ_EXPR
,
5936 op
, fold_convert (TREE_TYPE (op
), min
),
5939 register_edge_assert_for (op
, e
, LE_EXPR
, op
,
5940 fold_convert (TREE_TYPE (op
), max
),
5942 finish_register_edge_assert_for (e
, bsi
, asserts
);
5947 if (!live_on_edge (default_edge
, op
))
5950 /* Now register along the default label assertions that correspond to the
5951 anti-range of each label. */
5952 int insertion_limit
= PARAM_VALUE (PARAM_MAX_VRP_SWITCH_ASSERTIONS
);
5953 if (insertion_limit
== 0)
5956 /* We can't do this if the default case shares a label with another case. */
5957 tree default_cl
= gimple_switch_default_label (last
);
5958 for (idx
= 1; idx
< n
; idx
++)
5961 tree cl
= gimple_switch_label (last
, idx
);
5962 if (CASE_LABEL (cl
) == CASE_LABEL (default_cl
))
5965 min
= CASE_LOW (cl
);
5966 max
= CASE_HIGH (cl
);
5968 /* Combine contiguous case ranges to reduce the number of assertions
5970 for (idx
= idx
+ 1; idx
< n
; idx
++)
5972 tree next_min
, next_max
;
5973 tree next_cl
= gimple_switch_label (last
, idx
);
5974 if (CASE_LABEL (next_cl
) == CASE_LABEL (default_cl
))
5977 next_min
= CASE_LOW (next_cl
);
5978 next_max
= CASE_HIGH (next_cl
);
5980 wide_int difference
= (wi::to_wide (next_min
)
5981 - wi::to_wide (max
? max
: min
));
5982 if (wi::eq_p (difference
, 1))
5983 max
= next_max
? next_max
: next_min
;
5989 if (max
== NULL_TREE
)
5991 /* Register the assertion OP != MIN. */
5992 auto_vec
<assert_info
, 8> asserts
;
5993 min
= fold_convert (TREE_TYPE (op
), min
);
5994 register_edge_assert_for (op
, default_edge
, NE_EXPR
, op
, min
,
5996 finish_register_edge_assert_for (default_edge
, bsi
, asserts
);
6000 /* Register the assertion (unsigned)OP - MIN > (MAX - MIN),
6001 which will give OP the anti-range ~[MIN,MAX]. */
6002 tree uop
= fold_convert (unsigned_type_for (TREE_TYPE (op
)), op
);
6003 min
= fold_convert (TREE_TYPE (uop
), min
);
6004 max
= fold_convert (TREE_TYPE (uop
), max
);
6006 tree lhs
= fold_build2 (MINUS_EXPR
, TREE_TYPE (uop
), uop
, min
);
6007 tree rhs
= int_const_binop (MINUS_EXPR
, max
, min
);
6008 register_new_assert_for (op
, lhs
, GT_EXPR
, rhs
,
6009 NULL
, default_edge
, bsi
);
6012 if (--insertion_limit
== 0)
6018 /* Traverse all the statements in block BB looking for statements that
6019 may generate useful assertions for the SSA names in their operand.
6020 If a statement produces a useful assertion A for name N_i, then the
6021 list of assertions already generated for N_i is scanned to
6022 determine if A is actually needed.
6024 If N_i already had the assertion A at a location dominating the
6025 current location, then nothing needs to be done. Otherwise, the
6026 new location for A is recorded instead.
6028 1- For every statement S in BB, all the variables used by S are
6029 added to bitmap FOUND_IN_SUBGRAPH.
6031 2- If statement S uses an operand N in a way that exposes a known
6032 value range for N, then if N was not already generated by an
6033 ASSERT_EXPR, create a new assert location for N. For instance,
6034 if N is a pointer and the statement dereferences it, we can
6035 assume that N is not NULL.
6037 3- COND_EXPRs are a special case of #2. We can derive range
6038 information from the predicate but need to insert different
6039 ASSERT_EXPRs for each of the sub-graphs rooted at the
6040 conditional block. If the last statement of BB is a conditional
6041 expression of the form 'X op Y', then
6043 a) Remove X and Y from the set FOUND_IN_SUBGRAPH.
6045 b) If the conditional is the only entry point to the sub-graph
6046 corresponding to the THEN_CLAUSE, recurse into it. On
6047 return, if X and/or Y are marked in FOUND_IN_SUBGRAPH, then
6048 an ASSERT_EXPR is added for the corresponding variable.
6050 c) Repeat step (b) on the ELSE_CLAUSE.
6052 d) Mark X and Y in FOUND_IN_SUBGRAPH.
6061 In this case, an assertion on the THEN clause is useful to
6062 determine that 'a' is always 9 on that edge. However, an assertion
6063 on the ELSE clause would be unnecessary.
6065 4- If BB does not end in a conditional expression, then we recurse
6066 into BB's dominator children.
6068 At the end of the recursive traversal, every SSA name will have a
6069 list of locations where ASSERT_EXPRs should be added. When a new
6070 location for name N is found, it is registered by calling
6071 register_new_assert_for. That function keeps track of all the
6072 registered assertions to prevent adding unnecessary assertions.
6073 For instance, if a pointer P_4 is dereferenced more than once in a
6074 dominator tree, only the location dominating all the dereference of
6075 P_4 will receive an ASSERT_EXPR. */
6078 find_assert_locations_1 (basic_block bb
, sbitmap live
)
6082 last
= last_stmt (bb
);
6084 /* If BB's last statement is a conditional statement involving integer
6085 operands, determine if we need to add ASSERT_EXPRs. */
6087 && gimple_code (last
) == GIMPLE_COND
6088 && !fp_predicate (last
)
6089 && !ZERO_SSA_OPERANDS (last
, SSA_OP_USE
))
6090 find_conditional_asserts (bb
, as_a
<gcond
*> (last
));
6092 /* If BB's last statement is a switch statement involving integer
6093 operands, determine if we need to add ASSERT_EXPRs. */
6095 && gimple_code (last
) == GIMPLE_SWITCH
6096 && !ZERO_SSA_OPERANDS (last
, SSA_OP_USE
))
6097 find_switch_asserts (bb
, as_a
<gswitch
*> (last
));
6099 /* Traverse all the statements in BB marking used names and looking
6100 for statements that may infer assertions for their used operands. */
6101 for (gimple_stmt_iterator si
= gsi_last_bb (bb
); !gsi_end_p (si
);
6108 stmt
= gsi_stmt (si
);
6110 if (is_gimple_debug (stmt
))
6113 /* See if we can derive an assertion for any of STMT's operands. */
6114 FOR_EACH_SSA_TREE_OPERAND (op
, stmt
, i
, SSA_OP_USE
)
6117 enum tree_code comp_code
;
6119 /* If op is not live beyond this stmt, do not bother to insert
6121 if (!bitmap_bit_p (live
, SSA_NAME_VERSION (op
)))
6124 /* If OP is used in such a way that we can infer a value
6125 range for it, and we don't find a previous assertion for
6126 it, create a new assertion location node for OP. */
6127 if (infer_value_range (stmt
, op
, &comp_code
, &value
))
6129 /* If we are able to infer a nonzero value range for OP,
6130 then walk backwards through the use-def chain to see if OP
6131 was set via a typecast.
6133 If so, then we can also infer a nonzero value range
6134 for the operand of the NOP_EXPR. */
6135 if (comp_code
== NE_EXPR
&& integer_zerop (value
))
6138 gimple
*def_stmt
= SSA_NAME_DEF_STMT (t
);
6140 while (is_gimple_assign (def_stmt
)
6141 && CONVERT_EXPR_CODE_P
6142 (gimple_assign_rhs_code (def_stmt
))
6144 (gimple_assign_rhs1 (def_stmt
)) == SSA_NAME
6146 (TREE_TYPE (gimple_assign_rhs1 (def_stmt
))))
6148 t
= gimple_assign_rhs1 (def_stmt
);
6149 def_stmt
= SSA_NAME_DEF_STMT (t
);
6151 /* Note we want to register the assert for the
6152 operand of the NOP_EXPR after SI, not after the
6154 if (bitmap_bit_p (live
, SSA_NAME_VERSION (t
)))
6155 register_new_assert_for (t
, t
, comp_code
, value
,
6160 register_new_assert_for (op
, op
, comp_code
, value
, bb
, NULL
, si
);
6165 FOR_EACH_SSA_TREE_OPERAND (op
, stmt
, i
, SSA_OP_USE
)
6166 bitmap_set_bit (live
, SSA_NAME_VERSION (op
));
6167 FOR_EACH_SSA_TREE_OPERAND (op
, stmt
, i
, SSA_OP_DEF
)
6168 bitmap_clear_bit (live
, SSA_NAME_VERSION (op
));
6171 /* Traverse all PHI nodes in BB, updating live. */
6172 for (gphi_iterator si
= gsi_start_phis (bb
); !gsi_end_p (si
);
6175 use_operand_p arg_p
;
6177 gphi
*phi
= si
.phi ();
6178 tree res
= gimple_phi_result (phi
);
6180 if (virtual_operand_p (res
))
6183 FOR_EACH_PHI_ARG (arg_p
, phi
, i
, SSA_OP_USE
)
6185 tree arg
= USE_FROM_PTR (arg_p
);
6186 if (TREE_CODE (arg
) == SSA_NAME
)
6187 bitmap_set_bit (live
, SSA_NAME_VERSION (arg
));
6190 bitmap_clear_bit (live
, SSA_NAME_VERSION (res
));
6194 /* Do an RPO walk over the function computing SSA name liveness
6195 on-the-fly and deciding on assert expressions to insert. */
6198 find_assert_locations (void)
6200 int *rpo
= XNEWVEC (int, last_basic_block_for_fn (cfun
));
6201 int *bb_rpo
= XNEWVEC (int, last_basic_block_for_fn (cfun
));
6202 int *last_rpo
= XCNEWVEC (int, last_basic_block_for_fn (cfun
));
6205 live
= XCNEWVEC (sbitmap
, last_basic_block_for_fn (cfun
));
6206 rpo_cnt
= pre_and_rev_post_order_compute (NULL
, rpo
, false);
6207 for (i
= 0; i
< rpo_cnt
; ++i
)
6210 /* Pre-seed loop latch liveness from loop header PHI nodes. Due to
6211 the order we compute liveness and insert asserts we otherwise
6212 fail to insert asserts into the loop latch. */
6214 FOR_EACH_LOOP (loop
, 0)
6216 i
= loop
->latch
->index
;
6217 unsigned int j
= single_succ_edge (loop
->latch
)->dest_idx
;
6218 for (gphi_iterator gsi
= gsi_start_phis (loop
->header
);
6219 !gsi_end_p (gsi
); gsi_next (&gsi
))
6221 gphi
*phi
= gsi
.phi ();
6222 if (virtual_operand_p (gimple_phi_result (phi
)))
6224 tree arg
= gimple_phi_arg_def (phi
, j
);
6225 if (TREE_CODE (arg
) == SSA_NAME
)
6227 if (live
[i
] == NULL
)
6229 live
[i
] = sbitmap_alloc (num_ssa_names
);
6230 bitmap_clear (live
[i
]);
6232 bitmap_set_bit (live
[i
], SSA_NAME_VERSION (arg
));
6237 for (i
= rpo_cnt
- 1; i
>= 0; --i
)
6239 basic_block bb
= BASIC_BLOCK_FOR_FN (cfun
, rpo
[i
]);
6245 live
[rpo
[i
]] = sbitmap_alloc (num_ssa_names
);
6246 bitmap_clear (live
[rpo
[i
]]);
6249 /* Process BB and update the live information with uses in
6251 find_assert_locations_1 (bb
, live
[rpo
[i
]]);
6253 /* Merge liveness into the predecessor blocks and free it. */
6254 if (!bitmap_empty_p (live
[rpo
[i
]]))
6257 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
6259 int pred
= e
->src
->index
;
6260 if ((e
->flags
& EDGE_DFS_BACK
) || pred
== ENTRY_BLOCK
)
6265 live
[pred
] = sbitmap_alloc (num_ssa_names
);
6266 bitmap_clear (live
[pred
]);
6268 bitmap_ior (live
[pred
], live
[pred
], live
[rpo
[i
]]);
6270 if (bb_rpo
[pred
] < pred_rpo
)
6271 pred_rpo
= bb_rpo
[pred
];
6274 /* Record the RPO number of the last visited block that needs
6275 live information from this block. */
6276 last_rpo
[rpo
[i
]] = pred_rpo
;
6280 sbitmap_free (live
[rpo
[i
]]);
6281 live
[rpo
[i
]] = NULL
;
6284 /* We can free all successors live bitmaps if all their
6285 predecessors have been visited already. */
6286 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
6287 if (last_rpo
[e
->dest
->index
] == i
6288 && live
[e
->dest
->index
])
6290 sbitmap_free (live
[e
->dest
->index
]);
6291 live
[e
->dest
->index
] = NULL
;
6296 XDELETEVEC (bb_rpo
);
6297 XDELETEVEC (last_rpo
);
6298 for (i
= 0; i
< last_basic_block_for_fn (cfun
); ++i
)
6300 sbitmap_free (live
[i
]);
6304 /* Create an ASSERT_EXPR for NAME and insert it in the location
6305 indicated by LOC. Return true if we made any edge insertions. */
6308 process_assert_insertions_for (tree name
, assert_locus
*loc
)
6310 /* Build the comparison expression NAME_i COMP_CODE VAL. */
6313 gimple
*assert_stmt
;
6317 /* If we have X <=> X do not insert an assert expr for that. */
6318 if (loc
->expr
== loc
->val
)
6321 cond
= build2 (loc
->comp_code
, boolean_type_node
, loc
->expr
, loc
->val
);
6322 assert_stmt
= build_assert_expr_for (cond
, name
);
6325 /* We have been asked to insert the assertion on an edge. This
6326 is used only by COND_EXPR and SWITCH_EXPR assertions. */
6327 gcc_checking_assert (gimple_code (gsi_stmt (loc
->si
)) == GIMPLE_COND
6328 || (gimple_code (gsi_stmt (loc
->si
))
6331 gsi_insert_on_edge (loc
->e
, assert_stmt
);
6335 /* If the stmt iterator points at the end then this is an insertion
6336 at the beginning of a block. */
6337 if (gsi_end_p (loc
->si
))
6339 gimple_stmt_iterator si
= gsi_after_labels (loc
->bb
);
6340 gsi_insert_before (&si
, assert_stmt
, GSI_SAME_STMT
);
6344 /* Otherwise, we can insert right after LOC->SI iff the
6345 statement must not be the last statement in the block. */
6346 stmt
= gsi_stmt (loc
->si
);
6347 if (!stmt_ends_bb_p (stmt
))
6349 gsi_insert_after (&loc
->si
, assert_stmt
, GSI_SAME_STMT
);
6353 /* If STMT must be the last statement in BB, we can only insert new
6354 assertions on the non-abnormal edge out of BB. Note that since
6355 STMT is not control flow, there may only be one non-abnormal/eh edge
6357 FOR_EACH_EDGE (e
, ei
, loc
->bb
->succs
)
6358 if (!(e
->flags
& (EDGE_ABNORMAL
|EDGE_EH
)))
6360 gsi_insert_on_edge (e
, assert_stmt
);
6367 /* Qsort helper for sorting assert locations. If stable is true, don't
6368 use iterative_hash_expr because it can be unstable for -fcompare-debug,
6369 on the other side some pointers might be NULL. */
6371 template <bool stable
>
6373 compare_assert_loc (const void *pa
, const void *pb
)
6375 assert_locus
* const a
= *(assert_locus
* const *)pa
;
6376 assert_locus
* const b
= *(assert_locus
* const *)pb
;
6378 /* If stable, some asserts might be optimized away already, sort
6388 if (a
->e
== NULL
&& b
->e
!= NULL
)
6390 else if (a
->e
!= NULL
&& b
->e
== NULL
)
6393 /* After the above checks, we know that (a->e == NULL) == (b->e == NULL),
6394 no need to test both a->e and b->e. */
6396 /* Sort after destination index. */
6399 else if (a
->e
->dest
->index
> b
->e
->dest
->index
)
6401 else if (a
->e
->dest
->index
< b
->e
->dest
->index
)
6404 /* Sort after comp_code. */
6405 if (a
->comp_code
> b
->comp_code
)
6407 else if (a
->comp_code
< b
->comp_code
)
6412 /* E.g. if a->val is ADDR_EXPR of a VAR_DECL, iterative_hash_expr
6413 uses DECL_UID of the VAR_DECL, so sorting might differ between
6414 -g and -g0. When doing the removal of redundant assert exprs
6415 and commonization to successors, this does not matter, but for
6416 the final sort needs to be stable. */
6424 ha
= iterative_hash_expr (a
->expr
, iterative_hash_expr (a
->val
, 0));
6425 hb
= iterative_hash_expr (b
->expr
, iterative_hash_expr (b
->val
, 0));
6428 /* Break the tie using hashing and source/bb index. */
6430 return (a
->e
!= NULL
6431 ? a
->e
->src
->index
- b
->e
->src
->index
6432 : a
->bb
->index
- b
->bb
->index
);
6433 return ha
> hb
? 1 : -1;
6436 /* Process all the insertions registered for every name N_i registered
6437 in NEED_ASSERT_FOR. The list of assertions to be inserted are
6438 found in ASSERTS_FOR[i]. */
6441 process_assert_insertions (void)
6445 bool update_edges_p
= false;
6446 int num_asserts
= 0;
6448 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6449 dump_all_asserts (dump_file
);
6451 EXECUTE_IF_SET_IN_BITMAP (need_assert_for
, 0, i
, bi
)
6453 assert_locus
*loc
= asserts_for
[i
];
6456 auto_vec
<assert_locus
*, 16> asserts
;
6457 for (; loc
; loc
= loc
->next
)
6458 asserts
.safe_push (loc
);
6459 asserts
.qsort (compare_assert_loc
<false>);
6461 /* Push down common asserts to successors and remove redundant ones. */
6463 assert_locus
*common
= NULL
;
6464 unsigned commonj
= 0;
6465 for (unsigned j
= 0; j
< asserts
.length (); ++j
)
6471 || loc
->e
->dest
!= common
->e
->dest
6472 || loc
->comp_code
!= common
->comp_code
6473 || ! operand_equal_p (loc
->val
, common
->val
, 0)
6474 || ! operand_equal_p (loc
->expr
, common
->expr
, 0))
6480 else if (loc
->e
== asserts
[j
-1]->e
)
6482 /* Remove duplicate asserts. */
6483 if (commonj
== j
- 1)
6488 free (asserts
[j
-1]);
6489 asserts
[j
-1] = NULL
;
6494 if (EDGE_COUNT (common
->e
->dest
->preds
) == ecnt
)
6496 /* We have the same assertion on all incoming edges of a BB.
6497 Insert it at the beginning of that block. */
6498 loc
->bb
= loc
->e
->dest
;
6500 loc
->si
= gsi_none ();
6502 /* Clear asserts commoned. */
6503 for (; commonj
!= j
; ++commonj
)
6504 if (asserts
[commonj
])
6506 free (asserts
[commonj
]);
6507 asserts
[commonj
] = NULL
;
6513 /* The asserts vector sorting above might be unstable for
6514 -fcompare-debug, sort again to ensure a stable sort. */
6515 asserts
.qsort (compare_assert_loc
<true>);
6516 for (unsigned j
= 0; j
< asserts
.length (); ++j
)
6521 update_edges_p
|= process_assert_insertions_for (ssa_name (i
), loc
);
6528 gsi_commit_edge_inserts ();
6530 statistics_counter_event (cfun
, "Number of ASSERT_EXPR expressions inserted",
6535 /* Traverse the flowgraph looking for conditional jumps to insert range
6536 expressions. These range expressions are meant to provide information
6537 to optimizations that need to reason in terms of value ranges. They
6538 will not be expanded into RTL. For instance, given:
6547 this pass will transform the code into:
6553 x = ASSERT_EXPR <x, x < y>
6558 y = ASSERT_EXPR <y, x >= y>
6562 The idea is that once copy and constant propagation have run, other
6563 optimizations will be able to determine what ranges of values can 'x'
6564 take in different paths of the code, simply by checking the reaching
6565 definition of 'x'. */
6568 insert_range_assertions (void)
6570 need_assert_for
= BITMAP_ALLOC (NULL
);
6571 asserts_for
= XCNEWVEC (assert_locus
*, num_ssa_names
);
6573 calculate_dominance_info (CDI_DOMINATORS
);
6575 find_assert_locations ();
6576 if (!bitmap_empty_p (need_assert_for
))
6578 process_assert_insertions ();
6579 update_ssa (TODO_update_ssa_no_phi
);
6582 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6584 fprintf (dump_file
, "\nSSA form after inserting ASSERT_EXPRs\n");
6585 dump_function_to_file (current_function_decl
, dump_file
, dump_flags
);
6589 BITMAP_FREE (need_assert_for
);
6592 class vrp_prop
: public ssa_propagation_engine
6595 enum ssa_prop_result
visit_stmt (gimple
*, edge
*, tree
*) FINAL OVERRIDE
;
6596 enum ssa_prop_result
visit_phi (gphi
*) FINAL OVERRIDE
;
6598 void vrp_initialize (void);
6599 void vrp_finalize (bool);
6600 void check_all_array_refs (void);
6601 void check_array_ref (location_t
, tree
, bool);
6602 void search_for_addr_array (tree
, location_t
);
6604 class vr_values vr_values
;
6605 /* Temporary delegator to minimize code churn. */
6606 value_range
*get_value_range (const_tree op
)
6607 { return vr_values
.get_value_range (op
); }
6608 void set_defs_to_varying (gimple
*stmt
)
6609 { return vr_values
.set_defs_to_varying (stmt
); }
6610 void extract_range_from_stmt (gimple
*stmt
, edge
*taken_edge_p
,
6611 tree
*output_p
, value_range
*vr
)
6612 { vr_values
.extract_range_from_stmt (stmt
, taken_edge_p
, output_p
, vr
); }
6613 bool update_value_range (const_tree op
, value_range
*vr
)
6614 { return vr_values
.update_value_range (op
, vr
); }
6615 void extract_range_basic (value_range
*vr
, gimple
*stmt
)
6616 { vr_values
.extract_range_basic (vr
, stmt
); }
6617 void extract_range_from_phi_node (gphi
*phi
, value_range
*vr
)
6618 { vr_values
.extract_range_from_phi_node (phi
, vr
); }
6621 /* Checks one ARRAY_REF in REF, located at LOCUS. Ignores flexible arrays
6622 and "struct" hacks. If VRP can determine that the
6623 array subscript is a constant, check if it is outside valid
6624 range. If the array subscript is a RANGE, warn if it is
6625 non-overlapping with valid range.
6626 IGNORE_OFF_BY_ONE is true if the ARRAY_REF is inside a ADDR_EXPR. */
6629 vrp_prop::check_array_ref (location_t location
, tree ref
,
6630 bool ignore_off_by_one
)
6632 value_range
*vr
= NULL
;
6633 tree low_sub
, up_sub
;
6634 tree low_bound
, up_bound
, up_bound_p1
;
6636 if (TREE_NO_WARNING (ref
))
6639 low_sub
= up_sub
= TREE_OPERAND (ref
, 1);
6640 up_bound
= array_ref_up_bound (ref
);
6642 /* Can not check flexible arrays. */
6644 || TREE_CODE (up_bound
) != INTEGER_CST
)
6647 /* Accesses to trailing arrays via pointers may access storage
6648 beyond the types array bounds. */
6649 if (warn_array_bounds
< 2
6650 && array_at_struct_end_p (ref
))
6653 low_bound
= array_ref_low_bound (ref
);
6654 up_bound_p1
= int_const_binop (PLUS_EXPR
, up_bound
,
6655 build_int_cst (TREE_TYPE (up_bound
), 1));
6658 if (tree_int_cst_equal (low_bound
, up_bound_p1
))
6660 warning_at (location
, OPT_Warray_bounds
,
6661 "array subscript is above array bounds");
6662 TREE_NO_WARNING (ref
) = 1;
6665 if (TREE_CODE (low_sub
) == SSA_NAME
)
6667 vr
= get_value_range (low_sub
);
6668 if (vr
->type
== VR_RANGE
|| vr
->type
== VR_ANTI_RANGE
)
6670 low_sub
= vr
->type
== VR_RANGE
? vr
->max
: vr
->min
;
6671 up_sub
= vr
->type
== VR_RANGE
? vr
->min
: vr
->max
;
6675 if (vr
&& vr
->type
== VR_ANTI_RANGE
)
6677 if (TREE_CODE (up_sub
) == INTEGER_CST
6678 && (ignore_off_by_one
6679 ? tree_int_cst_lt (up_bound
, up_sub
)
6680 : tree_int_cst_le (up_bound
, up_sub
))
6681 && TREE_CODE (low_sub
) == INTEGER_CST
6682 && tree_int_cst_le (low_sub
, low_bound
))
6684 warning_at (location
, OPT_Warray_bounds
,
6685 "array subscript is outside array bounds");
6686 TREE_NO_WARNING (ref
) = 1;
6689 else if (TREE_CODE (up_sub
) == INTEGER_CST
6690 && (ignore_off_by_one
6691 ? !tree_int_cst_le (up_sub
, up_bound_p1
)
6692 : !tree_int_cst_le (up_sub
, up_bound
)))
6694 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6696 fprintf (dump_file
, "Array bound warning for ");
6697 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, ref
);
6698 fprintf (dump_file
, "\n");
6700 warning_at (location
, OPT_Warray_bounds
,
6701 "array subscript is above array bounds");
6702 TREE_NO_WARNING (ref
) = 1;
6704 else if (TREE_CODE (low_sub
) == INTEGER_CST
6705 && tree_int_cst_lt (low_sub
, low_bound
))
6707 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6709 fprintf (dump_file
, "Array bound warning for ");
6710 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, ref
);
6711 fprintf (dump_file
, "\n");
6713 warning_at (location
, OPT_Warray_bounds
,
6714 "array subscript is below array bounds");
6715 TREE_NO_WARNING (ref
) = 1;
6719 /* Searches if the expr T, located at LOCATION computes
6720 address of an ARRAY_REF, and call check_array_ref on it. */
6723 vrp_prop::search_for_addr_array (tree t
, location_t location
)
6725 /* Check each ARRAY_REFs in the reference chain. */
6728 if (TREE_CODE (t
) == ARRAY_REF
)
6729 check_array_ref (location
, t
, true /*ignore_off_by_one*/);
6731 t
= TREE_OPERAND (t
, 0);
6733 while (handled_component_p (t
));
6735 if (TREE_CODE (t
) == MEM_REF
6736 && TREE_CODE (TREE_OPERAND (t
, 0)) == ADDR_EXPR
6737 && !TREE_NO_WARNING (t
))
6739 tree tem
= TREE_OPERAND (TREE_OPERAND (t
, 0), 0);
6740 tree low_bound
, up_bound
, el_sz
;
6742 if (TREE_CODE (TREE_TYPE (tem
)) != ARRAY_TYPE
6743 || TREE_CODE (TREE_TYPE (TREE_TYPE (tem
))) == ARRAY_TYPE
6744 || !TYPE_DOMAIN (TREE_TYPE (tem
)))
6747 low_bound
= TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (tem
)));
6748 up_bound
= TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (tem
)));
6749 el_sz
= TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (tem
)));
6751 || TREE_CODE (low_bound
) != INTEGER_CST
6753 || TREE_CODE (up_bound
) != INTEGER_CST
6755 || TREE_CODE (el_sz
) != INTEGER_CST
)
6758 idx
= mem_ref_offset (t
);
6759 idx
= wi::sdiv_trunc (idx
, wi::to_offset (el_sz
));
6762 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6764 fprintf (dump_file
, "Array bound warning for ");
6765 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, t
);
6766 fprintf (dump_file
, "\n");
6768 warning_at (location
, OPT_Warray_bounds
,
6769 "array subscript is below array bounds");
6770 TREE_NO_WARNING (t
) = 1;
6772 else if (idx
> (wi::to_offset (up_bound
)
6773 - wi::to_offset (low_bound
) + 1))
6775 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
6777 fprintf (dump_file
, "Array bound warning for ");
6778 dump_generic_expr (MSG_NOTE
, TDF_SLIM
, t
);
6779 fprintf (dump_file
, "\n");
6781 warning_at (location
, OPT_Warray_bounds
,
6782 "array subscript is above array bounds");
6783 TREE_NO_WARNING (t
) = 1;
6788 /* walk_tree() callback that checks if *TP is
6789 an ARRAY_REF inside an ADDR_EXPR (in which an array
6790 subscript one outside the valid range is allowed). Call
6791 check_array_ref for each ARRAY_REF found. The location is
6795 check_array_bounds (tree
*tp
, int *walk_subtree
, void *data
)
6798 struct walk_stmt_info
*wi
= (struct walk_stmt_info
*) data
;
6799 location_t location
;
6801 if (EXPR_HAS_LOCATION (t
))
6802 location
= EXPR_LOCATION (t
);
6804 location
= gimple_location (wi
->stmt
);
6806 *walk_subtree
= TRUE
;
6808 vrp_prop
*vrp_prop
= (class vrp_prop
*)wi
->info
;
6809 if (TREE_CODE (t
) == ARRAY_REF
)
6810 vrp_prop
->check_array_ref (location
, t
, false /*ignore_off_by_one*/);
6812 else if (TREE_CODE (t
) == ADDR_EXPR
)
6814 vrp_prop
->search_for_addr_array (t
, location
);
6815 *walk_subtree
= FALSE
;
6821 /* Walk over all statements of all reachable BBs and call check_array_bounds
6825 vrp_prop::check_all_array_refs ()
6828 gimple_stmt_iterator si
;
6830 FOR_EACH_BB_FN (bb
, cfun
)
6834 bool executable
= false;
6836 /* Skip blocks that were found to be unreachable. */
6837 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
6838 executable
|= !!(e
->flags
& EDGE_EXECUTABLE
);
6842 for (si
= gsi_start_bb (bb
); !gsi_end_p (si
); gsi_next (&si
))
6844 gimple
*stmt
= gsi_stmt (si
);
6845 struct walk_stmt_info wi
;
6846 if (!gimple_has_location (stmt
)
6847 || is_gimple_debug (stmt
))
6850 memset (&wi
, 0, sizeof (wi
));
6854 walk_gimple_op (gsi_stmt (si
),
6861 /* Return true if all imm uses of VAR are either in STMT, or
6862 feed (optionally through a chain of single imm uses) GIMPLE_COND
6863 in basic block COND_BB. */
6866 all_imm_uses_in_stmt_or_feed_cond (tree var
, gimple
*stmt
, basic_block cond_bb
)
6868 use_operand_p use_p
, use2_p
;
6869 imm_use_iterator iter
;
6871 FOR_EACH_IMM_USE_FAST (use_p
, iter
, var
)
6872 if (USE_STMT (use_p
) != stmt
)
6874 gimple
*use_stmt
= USE_STMT (use_p
), *use_stmt2
;
6875 if (is_gimple_debug (use_stmt
))
6877 while (is_gimple_assign (use_stmt
)
6878 && TREE_CODE (gimple_assign_lhs (use_stmt
)) == SSA_NAME
6879 && single_imm_use (gimple_assign_lhs (use_stmt
),
6880 &use2_p
, &use_stmt2
))
6881 use_stmt
= use_stmt2
;
6882 if (gimple_code (use_stmt
) != GIMPLE_COND
6883 || gimple_bb (use_stmt
) != cond_bb
)
6896 __builtin_unreachable ();
6898 x_5 = ASSERT_EXPR <x_3, ...>;
6899 If x_3 has no other immediate uses (checked by caller),
6900 var is the x_3 var from ASSERT_EXPR, we can clear low 5 bits
6901 from the non-zero bitmask. */
6904 maybe_set_nonzero_bits (basic_block bb
, tree var
)
6906 edge e
= single_pred_edge (bb
);
6907 basic_block cond_bb
= e
->src
;
6908 gimple
*stmt
= last_stmt (cond_bb
);
6912 || gimple_code (stmt
) != GIMPLE_COND
6913 || gimple_cond_code (stmt
) != ((e
->flags
& EDGE_TRUE_VALUE
)
6914 ? EQ_EXPR
: NE_EXPR
)
6915 || TREE_CODE (gimple_cond_lhs (stmt
)) != SSA_NAME
6916 || !integer_zerop (gimple_cond_rhs (stmt
)))
6919 stmt
= SSA_NAME_DEF_STMT (gimple_cond_lhs (stmt
));
6920 if (!is_gimple_assign (stmt
)
6921 || gimple_assign_rhs_code (stmt
) != BIT_AND_EXPR
6922 || TREE_CODE (gimple_assign_rhs2 (stmt
)) != INTEGER_CST
)
6924 if (gimple_assign_rhs1 (stmt
) != var
)
6928 if (TREE_CODE (gimple_assign_rhs1 (stmt
)) != SSA_NAME
)
6930 stmt2
= SSA_NAME_DEF_STMT (gimple_assign_rhs1 (stmt
));
6931 if (!gimple_assign_cast_p (stmt2
)
6932 || gimple_assign_rhs1 (stmt2
) != var
6933 || !CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt2
))
6934 || (TYPE_PRECISION (TREE_TYPE (gimple_assign_rhs1 (stmt
)))
6935 != TYPE_PRECISION (TREE_TYPE (var
))))
6938 cst
= gimple_assign_rhs2 (stmt
);
6939 set_nonzero_bits (var
, wi::bit_and_not (get_nonzero_bits (var
),
6940 wi::to_wide (cst
)));
6943 /* Convert range assertion expressions into the implied copies and
6944 copy propagate away the copies. Doing the trivial copy propagation
6945 here avoids the need to run the full copy propagation pass after
6948 FIXME, this will eventually lead to copy propagation removing the
6949 names that had useful range information attached to them. For
6950 instance, if we had the assertion N_i = ASSERT_EXPR <N_j, N_j > 3>,
6951 then N_i will have the range [3, +INF].
6953 However, by converting the assertion into the implied copy
6954 operation N_i = N_j, we will then copy-propagate N_j into the uses
6955 of N_i and lose the range information. We may want to hold on to
6956 ASSERT_EXPRs a little while longer as the ranges could be used in
6957 things like jump threading.
6959 The problem with keeping ASSERT_EXPRs around is that passes after
6960 VRP need to handle them appropriately.
6962 Another approach would be to make the range information a first
6963 class property of the SSA_NAME so that it can be queried from
6964 any pass. This is made somewhat more complex by the need for
6965 multiple ranges to be associated with one SSA_NAME. */
6968 remove_range_assertions (void)
6971 gimple_stmt_iterator si
;
6972 /* 1 if looking at ASSERT_EXPRs immediately at the beginning of
6973 a basic block preceeded by GIMPLE_COND branching to it and
6974 __builtin_trap, -1 if not yet checked, 0 otherwise. */
6977 /* Note that the BSI iterator bump happens at the bottom of the
6978 loop and no bump is necessary if we're removing the statement
6979 referenced by the current BSI. */
6980 FOR_EACH_BB_FN (bb
, cfun
)
6981 for (si
= gsi_after_labels (bb
), is_unreachable
= -1; !gsi_end_p (si
);)
6983 gimple
*stmt
= gsi_stmt (si
);
6985 if (is_gimple_assign (stmt
)
6986 && gimple_assign_rhs_code (stmt
) == ASSERT_EXPR
)
6988 tree lhs
= gimple_assign_lhs (stmt
);
6989 tree rhs
= gimple_assign_rhs1 (stmt
);
6992 var
= ASSERT_EXPR_VAR (rhs
);
6994 if (TREE_CODE (var
) == SSA_NAME
6995 && !POINTER_TYPE_P (TREE_TYPE (lhs
))
6996 && SSA_NAME_RANGE_INFO (lhs
))
6998 if (is_unreachable
== -1)
7001 if (single_pred_p (bb
)
7002 && assert_unreachable_fallthru_edge_p
7003 (single_pred_edge (bb
)))
7007 if (x_7 >= 10 && x_7 < 20)
7008 __builtin_unreachable ();
7009 x_8 = ASSERT_EXPR <x_7, ...>;
7010 if the only uses of x_7 are in the ASSERT_EXPR and
7011 in the condition. In that case, we can copy the
7012 range info from x_8 computed in this pass also
7015 && all_imm_uses_in_stmt_or_feed_cond (var
, stmt
,
7018 set_range_info (var
, SSA_NAME_RANGE_TYPE (lhs
),
7019 SSA_NAME_RANGE_INFO (lhs
)->get_min (),
7020 SSA_NAME_RANGE_INFO (lhs
)->get_max ());
7021 maybe_set_nonzero_bits (bb
, var
);
7025 /* Propagate the RHS into every use of the LHS. For SSA names
7026 also propagate abnormals as it merely restores the original
7027 IL in this case (an replace_uses_by would assert). */
7028 if (TREE_CODE (var
) == SSA_NAME
)
7030 imm_use_iterator iter
;
7031 use_operand_p use_p
;
7033 FOR_EACH_IMM_USE_STMT (use_stmt
, iter
, lhs
)
7034 FOR_EACH_IMM_USE_ON_STMT (use_p
, iter
)
7035 SET_USE (use_p
, var
);
7038 replace_uses_by (lhs
, var
);
7040 /* And finally, remove the copy, it is not needed. */
7041 gsi_remove (&si
, true);
7042 release_defs (stmt
);
7046 if (!is_gimple_debug (gsi_stmt (si
)))
7054 /* Return true if STMT is interesting for VRP. */
7057 stmt_interesting_for_vrp (gimple
*stmt
)
7059 if (gimple_code (stmt
) == GIMPLE_PHI
)
7061 tree res
= gimple_phi_result (stmt
);
7062 return (!virtual_operand_p (res
)
7063 && (INTEGRAL_TYPE_P (TREE_TYPE (res
))
7064 || POINTER_TYPE_P (TREE_TYPE (res
))));
7066 else if (is_gimple_assign (stmt
) || is_gimple_call (stmt
))
7068 tree lhs
= gimple_get_lhs (stmt
);
7070 /* In general, assignments with virtual operands are not useful
7071 for deriving ranges, with the obvious exception of calls to
7072 builtin functions. */
7073 if (lhs
&& TREE_CODE (lhs
) == SSA_NAME
7074 && (INTEGRAL_TYPE_P (TREE_TYPE (lhs
))
7075 || POINTER_TYPE_P (TREE_TYPE (lhs
)))
7076 && (is_gimple_call (stmt
)
7077 || !gimple_vuse (stmt
)))
7079 else if (is_gimple_call (stmt
) && gimple_call_internal_p (stmt
))
7080 switch (gimple_call_internal_fn (stmt
))
7082 case IFN_ADD_OVERFLOW
:
7083 case IFN_SUB_OVERFLOW
:
7084 case IFN_MUL_OVERFLOW
:
7085 case IFN_ATOMIC_COMPARE_EXCHANGE
:
7086 /* These internal calls return _Complex integer type,
7087 but are interesting to VRP nevertheless. */
7088 if (lhs
&& TREE_CODE (lhs
) == SSA_NAME
)
7095 else if (gimple_code (stmt
) == GIMPLE_COND
7096 || gimple_code (stmt
) == GIMPLE_SWITCH
)
7102 /* Initialize VRP lattice. */
7104 vr_values::vr_values () : vrp_value_range_pool ("Tree VRP value ranges")
7106 values_propagated
= false;
7107 num_vr_values
= num_ssa_names
;
7108 vr_value
= XCNEWVEC (value_range
*, num_vr_values
);
7109 vr_phi_edge_counts
= XCNEWVEC (int, num_ssa_names
);
7110 bitmap_obstack_initialize (&vrp_equiv_obstack
);
7113 /* Initialization required by ssa_propagate engine. */
7116 vrp_prop::vrp_initialize ()
7120 FOR_EACH_BB_FN (bb
, cfun
)
7122 for (gphi_iterator si
= gsi_start_phis (bb
); !gsi_end_p (si
);
7125 gphi
*phi
= si
.phi ();
7126 if (!stmt_interesting_for_vrp (phi
))
7128 tree lhs
= PHI_RESULT (phi
);
7129 set_value_range_to_varying (get_value_range (lhs
));
7130 prop_set_simulate_again (phi
, false);
7133 prop_set_simulate_again (phi
, true);
7136 for (gimple_stmt_iterator si
= gsi_start_bb (bb
); !gsi_end_p (si
);
7139 gimple
*stmt
= gsi_stmt (si
);
7141 /* If the statement is a control insn, then we do not
7142 want to avoid simulating the statement once. Failure
7143 to do so means that those edges will never get added. */
7144 if (stmt_ends_bb_p (stmt
))
7145 prop_set_simulate_again (stmt
, true);
7146 else if (!stmt_interesting_for_vrp (stmt
))
7148 set_defs_to_varying (stmt
);
7149 prop_set_simulate_again (stmt
, false);
7152 prop_set_simulate_again (stmt
, true);
7158 static class vr_values
*x_vr_values
;
7160 /* Return the singleton value-range for NAME or NAME. */
7163 vrp_valueize (tree name
)
7165 if (TREE_CODE (name
) == SSA_NAME
)
7167 value_range
*vr
= x_vr_values
->get_value_range (name
);
7168 if (vr
->type
== VR_RANGE
7169 && (TREE_CODE (vr
->min
) == SSA_NAME
7170 || is_gimple_min_invariant (vr
->min
))
7171 && vrp_operand_equal_p (vr
->min
, vr
->max
))
7177 /* Return the singleton value-range for NAME if that is a constant
7178 but signal to not follow SSA edges. */
7181 vrp_valueize_1 (tree name
)
7183 if (TREE_CODE (name
) == SSA_NAME
)
7185 /* If the definition may be simulated again we cannot follow
7186 this SSA edge as the SSA propagator does not necessarily
7187 re-visit the use. */
7188 gimple
*def_stmt
= SSA_NAME_DEF_STMT (name
);
7189 if (!gimple_nop_p (def_stmt
)
7190 && prop_simulate_again_p (def_stmt
))
7192 value_range
*vr
= x_vr_values
->get_value_range (name
);
7193 if (range_int_cst_singleton_p (vr
))
7199 /* Visit assignment STMT. If it produces an interesting range, record
7200 the range in VR and set LHS to OUTPUT_P. */
7203 vr_values::vrp_visit_assignment_or_call (gimple
*stmt
, tree
*output_p
,
7207 enum gimple_code code
= gimple_code (stmt
);
7208 lhs
= gimple_get_lhs (stmt
);
7209 *output_p
= NULL_TREE
;
7211 /* We only keep track of ranges in integral and pointer types. */
7212 if (TREE_CODE (lhs
) == SSA_NAME
7213 && ((INTEGRAL_TYPE_P (TREE_TYPE (lhs
))
7214 /* It is valid to have NULL MIN/MAX values on a type. See
7215 build_range_type. */
7216 && TYPE_MIN_VALUE (TREE_TYPE (lhs
))
7217 && TYPE_MAX_VALUE (TREE_TYPE (lhs
)))
7218 || POINTER_TYPE_P (TREE_TYPE (lhs
))))
7222 /* Try folding the statement to a constant first. */
7224 tree tem
= gimple_fold_stmt_to_constant_1 (stmt
, vrp_valueize
,
7229 if (TREE_CODE (tem
) == SSA_NAME
7230 && (SSA_NAME_IS_DEFAULT_DEF (tem
)
7231 || ! prop_simulate_again_p (SSA_NAME_DEF_STMT (tem
))))
7233 extract_range_from_ssa_name (vr
, tem
);
7236 else if (is_gimple_min_invariant (tem
))
7238 set_value_range_to_value (vr
, tem
, NULL
);
7242 /* Then dispatch to value-range extracting functions. */
7243 if (code
== GIMPLE_CALL
)
7244 extract_range_basic (vr
, stmt
);
7246 extract_range_from_assignment (vr
, as_a
<gassign
*> (stmt
));
7250 /* Helper that gets the value range of the SSA_NAME with version I
7251 or a symbolic range containing the SSA_NAME only if the value range
7252 is varying or undefined. */
7255 vr_values::get_vr_for_comparison (int i
)
7257 value_range vr
= *get_value_range (ssa_name (i
));
7259 /* If name N_i does not have a valid range, use N_i as its own
7260 range. This allows us to compare against names that may
7261 have N_i in their ranges. */
7262 if (vr
.type
== VR_VARYING
|| vr
.type
== VR_UNDEFINED
)
7265 vr
.min
= ssa_name (i
);
7266 vr
.max
= ssa_name (i
);
7272 /* Compare all the value ranges for names equivalent to VAR with VAL
7273 using comparison code COMP. Return the same value returned by
7274 compare_range_with_value, including the setting of
7275 *STRICT_OVERFLOW_P. */
7278 vr_values::compare_name_with_value (enum tree_code comp
, tree var
, tree val
,
7279 bool *strict_overflow_p
, bool use_equiv_p
)
7285 int used_strict_overflow
;
7287 value_range equiv_vr
;
7289 /* Get the set of equivalences for VAR. */
7290 e
= get_value_range (var
)->equiv
;
7292 /* Start at -1. Set it to 0 if we do a comparison without relying
7293 on overflow, or 1 if all comparisons rely on overflow. */
7294 used_strict_overflow
= -1;
7296 /* Compare vars' value range with val. */
7297 equiv_vr
= get_vr_for_comparison (SSA_NAME_VERSION (var
));
7299 retval
= compare_range_with_value (comp
, &equiv_vr
, val
, &sop
);
7301 used_strict_overflow
= sop
? 1 : 0;
7303 /* If the equiv set is empty we have done all work we need to do. */
7307 && used_strict_overflow
> 0)
7308 *strict_overflow_p
= true;
7312 EXECUTE_IF_SET_IN_BITMAP (e
, 0, i
, bi
)
7314 tree name
= ssa_name (i
);
7319 && ! SSA_NAME_IS_DEFAULT_DEF (name
)
7320 && prop_simulate_again_p (SSA_NAME_DEF_STMT (name
)))
7323 equiv_vr
= get_vr_for_comparison (i
);
7325 t
= compare_range_with_value (comp
, &equiv_vr
, val
, &sop
);
7328 /* If we get different answers from different members
7329 of the equivalence set this check must be in a dead
7330 code region. Folding it to a trap representation
7331 would be correct here. For now just return don't-know. */
7341 used_strict_overflow
= 0;
7342 else if (used_strict_overflow
< 0)
7343 used_strict_overflow
= 1;
7348 && used_strict_overflow
> 0)
7349 *strict_overflow_p
= true;
7355 /* Given a comparison code COMP and names N1 and N2, compare all the
7356 ranges equivalent to N1 against all the ranges equivalent to N2
7357 to determine the value of N1 COMP N2. Return the same value
7358 returned by compare_ranges. Set *STRICT_OVERFLOW_P to indicate
7359 whether we relied on undefined signed overflow in the comparison. */
7363 vr_values::compare_names (enum tree_code comp
, tree n1
, tree n2
,
7364 bool *strict_overflow_p
)
7368 bitmap_iterator bi1
, bi2
;
7370 int used_strict_overflow
;
7371 static bitmap_obstack
*s_obstack
= NULL
;
7372 static bitmap s_e1
= NULL
, s_e2
= NULL
;
7374 /* Compare the ranges of every name equivalent to N1 against the
7375 ranges of every name equivalent to N2. */
7376 e1
= get_value_range (n1
)->equiv
;
7377 e2
= get_value_range (n2
)->equiv
;
7379 /* Use the fake bitmaps if e1 or e2 are not available. */
7380 if (s_obstack
== NULL
)
7382 s_obstack
= XNEW (bitmap_obstack
);
7383 bitmap_obstack_initialize (s_obstack
);
7384 s_e1
= BITMAP_ALLOC (s_obstack
);
7385 s_e2
= BITMAP_ALLOC (s_obstack
);
7392 /* Add N1 and N2 to their own set of equivalences to avoid
7393 duplicating the body of the loop just to check N1 and N2
7395 bitmap_set_bit (e1
, SSA_NAME_VERSION (n1
));
7396 bitmap_set_bit (e2
, SSA_NAME_VERSION (n2
));
7398 /* If the equivalence sets have a common intersection, then the two
7399 names can be compared without checking their ranges. */
7400 if (bitmap_intersect_p (e1
, e2
))
7402 bitmap_clear_bit (e1
, SSA_NAME_VERSION (n1
));
7403 bitmap_clear_bit (e2
, SSA_NAME_VERSION (n2
));
7405 return (comp
== EQ_EXPR
|| comp
== GE_EXPR
|| comp
== LE_EXPR
)
7407 : boolean_false_node
;
7410 /* Start at -1. Set it to 0 if we do a comparison without relying
7411 on overflow, or 1 if all comparisons rely on overflow. */
7412 used_strict_overflow
= -1;
7414 /* Otherwise, compare all the equivalent ranges. First, add N1 and
7415 N2 to their own set of equivalences to avoid duplicating the body
7416 of the loop just to check N1 and N2 ranges. */
7417 EXECUTE_IF_SET_IN_BITMAP (e1
, 0, i1
, bi1
)
7419 if (! ssa_name (i1
))
7422 value_range vr1
= get_vr_for_comparison (i1
);
7424 t
= retval
= NULL_TREE
;
7425 EXECUTE_IF_SET_IN_BITMAP (e2
, 0, i2
, bi2
)
7427 if (! ssa_name (i2
))
7432 value_range vr2
= get_vr_for_comparison (i2
);
7434 t
= compare_ranges (comp
, &vr1
, &vr2
, &sop
);
7437 /* If we get different answers from different members
7438 of the equivalence set this check must be in a dead
7439 code region. Folding it to a trap representation
7440 would be correct here. For now just return don't-know. */
7444 bitmap_clear_bit (e1
, SSA_NAME_VERSION (n1
));
7445 bitmap_clear_bit (e2
, SSA_NAME_VERSION (n2
));
7451 used_strict_overflow
= 0;
7452 else if (used_strict_overflow
< 0)
7453 used_strict_overflow
= 1;
7459 bitmap_clear_bit (e1
, SSA_NAME_VERSION (n1
));
7460 bitmap_clear_bit (e2
, SSA_NAME_VERSION (n2
));
7461 if (used_strict_overflow
> 0)
7462 *strict_overflow_p
= true;
7467 /* None of the equivalent ranges are useful in computing this
7469 bitmap_clear_bit (e1
, SSA_NAME_VERSION (n1
));
7470 bitmap_clear_bit (e2
, SSA_NAME_VERSION (n2
));
7474 /* Helper function for vrp_evaluate_conditional_warnv & other
7478 vr_values::vrp_evaluate_conditional_warnv_with_ops_using_ranges
7479 (enum tree_code code
, tree op0
, tree op1
, bool * strict_overflow_p
)
7481 value_range
*vr0
, *vr1
;
7483 vr0
= (TREE_CODE (op0
) == SSA_NAME
) ? get_value_range (op0
) : NULL
;
7484 vr1
= (TREE_CODE (op1
) == SSA_NAME
) ? get_value_range (op1
) : NULL
;
7486 tree res
= NULL_TREE
;
7488 res
= compare_ranges (code
, vr0
, vr1
, strict_overflow_p
);
7490 res
= compare_range_with_value (code
, vr0
, op1
, strict_overflow_p
);
7492 res
= (compare_range_with_value
7493 (swap_tree_comparison (code
), vr1
, op0
, strict_overflow_p
));
7497 /* Helper function for vrp_evaluate_conditional_warnv. */
7500 vr_values::vrp_evaluate_conditional_warnv_with_ops (enum tree_code code
,
7503 bool *strict_overflow_p
,
7508 *only_ranges
= true;
7510 /* We only deal with integral and pointer types. */
7511 if (!INTEGRAL_TYPE_P (TREE_TYPE (op0
))
7512 && !POINTER_TYPE_P (TREE_TYPE (op0
)))
7515 /* If OP0 CODE OP1 is an overflow comparison, if it can be expressed
7516 as a simple equality test, then prefer that over its current form
7519 An overflow test which collapses to an equality test can always be
7520 expressed as a comparison of one argument against zero. Overflow
7521 occurs when the chosen argument is zero and does not occur if the
7522 chosen argument is not zero. */
7524 if (overflow_comparison_p (code
, op0
, op1
, use_equiv_p
, &x
))
7526 wide_int max
= wi::max_value (TYPE_PRECISION (TREE_TYPE (op0
)), UNSIGNED
);
7527 /* B = A - 1; if (A < B) -> B = A - 1; if (A == 0)
7528 B = A - 1; if (A > B) -> B = A - 1; if (A != 0)
7529 B = A + 1; if (B < A) -> B = A + 1; if (B == 0)
7530 B = A + 1; if (B > A) -> B = A + 1; if (B != 0) */
7531 if (integer_zerop (x
))
7534 code
= (code
== LT_EXPR
|| code
== LE_EXPR
) ? EQ_EXPR
: NE_EXPR
;
7536 /* B = A + 1; if (A > B) -> B = A + 1; if (B == 0)
7537 B = A + 1; if (A < B) -> B = A + 1; if (B != 0)
7538 B = A - 1; if (B > A) -> B = A - 1; if (A == 0)
7539 B = A - 1; if (B < A) -> B = A - 1; if (A != 0) */
7540 else if (wi::to_wide (x
) == max
- 1)
7543 op1
= wide_int_to_tree (TREE_TYPE (op0
), 0);
7544 code
= (code
== GT_EXPR
|| code
== GE_EXPR
) ? EQ_EXPR
: NE_EXPR
;
7548 if ((ret
= vrp_evaluate_conditional_warnv_with_ops_using_ranges
7549 (code
, op0
, op1
, strict_overflow_p
)))
7552 *only_ranges
= false;
7553 /* Do not use compare_names during propagation, it's quadratic. */
7554 if (TREE_CODE (op0
) == SSA_NAME
&& TREE_CODE (op1
) == SSA_NAME
7556 return compare_names (code
, op0
, op1
, strict_overflow_p
);
7557 else if (TREE_CODE (op0
) == SSA_NAME
)
7558 return compare_name_with_value (code
, op0
, op1
,
7559 strict_overflow_p
, use_equiv_p
);
7560 else if (TREE_CODE (op1
) == SSA_NAME
)
7561 return compare_name_with_value (swap_tree_comparison (code
), op1
, op0
,
7562 strict_overflow_p
, use_equiv_p
);
7566 /* Given (CODE OP0 OP1) within STMT, try to simplify it based on value range
7567 information. Return NULL if the conditional can not be evaluated.
7568 The ranges of all the names equivalent with the operands in COND
7569 will be used when trying to compute the value. If the result is
7570 based on undefined signed overflow, issue a warning if
7574 vr_values::vrp_evaluate_conditional (tree_code code
, tree op0
,
7575 tree op1
, gimple
*stmt
)
7581 /* Some passes and foldings leak constants with overflow flag set
7582 into the IL. Avoid doing wrong things with these and bail out. */
7583 if ((TREE_CODE (op0
) == INTEGER_CST
7584 && TREE_OVERFLOW (op0
))
7585 || (TREE_CODE (op1
) == INTEGER_CST
7586 && TREE_OVERFLOW (op1
)))
7590 ret
= vrp_evaluate_conditional_warnv_with_ops (code
, op0
, op1
, true, &sop
,
7595 enum warn_strict_overflow_code wc
;
7596 const char* warnmsg
;
7598 if (is_gimple_min_invariant (ret
))
7600 wc
= WARN_STRICT_OVERFLOW_CONDITIONAL
;
7601 warnmsg
= G_("assuming signed overflow does not occur when "
7602 "simplifying conditional to constant");
7606 wc
= WARN_STRICT_OVERFLOW_COMPARISON
;
7607 warnmsg
= G_("assuming signed overflow does not occur when "
7608 "simplifying conditional");
7611 if (issue_strict_overflow_warning (wc
))
7613 location_t location
;
7615 if (!gimple_has_location (stmt
))
7616 location
= input_location
;
7618 location
= gimple_location (stmt
);
7619 warning_at (location
, OPT_Wstrict_overflow
, "%s", warnmsg
);
7623 if (warn_type_limits
7624 && ret
&& only_ranges
7625 && TREE_CODE_CLASS (code
) == tcc_comparison
7626 && TREE_CODE (op0
) == SSA_NAME
)
7628 /* If the comparison is being folded and the operand on the LHS
7629 is being compared against a constant value that is outside of
7630 the natural range of OP0's type, then the predicate will
7631 always fold regardless of the value of OP0. If -Wtype-limits
7632 was specified, emit a warning. */
7633 tree type
= TREE_TYPE (op0
);
7634 value_range
*vr0
= get_value_range (op0
);
7636 if (vr0
->type
== VR_RANGE
7637 && INTEGRAL_TYPE_P (type
)
7638 && vrp_val_is_min (vr0
->min
)
7639 && vrp_val_is_max (vr0
->max
)
7640 && is_gimple_min_invariant (op1
))
7642 location_t location
;
7644 if (!gimple_has_location (stmt
))
7645 location
= input_location
;
7647 location
= gimple_location (stmt
);
7649 warning_at (location
, OPT_Wtype_limits
,
7651 ? G_("comparison always false "
7652 "due to limited range of data type")
7653 : G_("comparison always true "
7654 "due to limited range of data type"));
7662 /* Visit conditional statement STMT. If we can determine which edge
7663 will be taken out of STMT's basic block, record it in
7664 *TAKEN_EDGE_P. Otherwise, set *TAKEN_EDGE_P to NULL. */
7667 vr_values::vrp_visit_cond_stmt (gcond
*stmt
, edge
*taken_edge_p
)
7671 *taken_edge_p
= NULL
;
7673 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7678 fprintf (dump_file
, "\nVisiting conditional with predicate: ");
7679 print_gimple_stmt (dump_file
, stmt
, 0);
7680 fprintf (dump_file
, "\nWith known ranges\n");
7682 FOR_EACH_SSA_TREE_OPERAND (use
, stmt
, i
, SSA_OP_USE
)
7684 fprintf (dump_file
, "\t");
7685 print_generic_expr (dump_file
, use
);
7686 fprintf (dump_file
, ": ");
7687 dump_value_range (dump_file
, vr_value
[SSA_NAME_VERSION (use
)]);
7690 fprintf (dump_file
, "\n");
7693 /* Compute the value of the predicate COND by checking the known
7694 ranges of each of its operands.
7696 Note that we cannot evaluate all the equivalent ranges here
7697 because those ranges may not yet be final and with the current
7698 propagation strategy, we cannot determine when the value ranges
7699 of the names in the equivalence set have changed.
7701 For instance, given the following code fragment
7705 i_14 = ASSERT_EXPR <i_5, i_5 != 0>
7709 Assume that on the first visit to i_14, i_5 has the temporary
7710 range [8, 8] because the second argument to the PHI function is
7711 not yet executable. We derive the range ~[0, 0] for i_14 and the
7712 equivalence set { i_5 }. So, when we visit 'if (i_14 == 1)' for
7713 the first time, since i_14 is equivalent to the range [8, 8], we
7714 determine that the predicate is always false.
7716 On the next round of propagation, i_13 is determined to be
7717 VARYING, which causes i_5 to drop down to VARYING. So, another
7718 visit to i_14 is scheduled. In this second visit, we compute the
7719 exact same range and equivalence set for i_14, namely ~[0, 0] and
7720 { i_5 }. But we did not have the previous range for i_5
7721 registered, so vrp_visit_assignment thinks that the range for
7722 i_14 has not changed. Therefore, the predicate 'if (i_14 == 1)'
7723 is not visited again, which stops propagation from visiting
7724 statements in the THEN clause of that if().
7726 To properly fix this we would need to keep the previous range
7727 value for the names in the equivalence set. This way we would've
7728 discovered that from one visit to the other i_5 changed from
7729 range [8, 8] to VR_VARYING.
7731 However, fixing this apparent limitation may not be worth the
7732 additional checking. Testing on several code bases (GCC, DLV,
7733 MICO, TRAMP3D and SPEC2000) showed that doing this results in
7734 4 more predicates folded in SPEC. */
7737 val
= vrp_evaluate_conditional_warnv_with_ops (gimple_cond_code (stmt
),
7738 gimple_cond_lhs (stmt
),
7739 gimple_cond_rhs (stmt
),
7742 *taken_edge_p
= find_taken_edge (gimple_bb (stmt
), val
);
7744 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7746 fprintf (dump_file
, "\nPredicate evaluates to: ");
7747 if (val
== NULL_TREE
)
7748 fprintf (dump_file
, "DON'T KNOW\n");
7750 print_generic_stmt (dump_file
, val
);
7754 /* Searches the case label vector VEC for the index *IDX of the CASE_LABEL
7755 that includes the value VAL. The search is restricted to the range
7756 [START_IDX, n - 1] where n is the size of VEC.
7758 If there is a CASE_LABEL for VAL, its index is placed in IDX and true is
7761 If there is no CASE_LABEL for VAL and there is one that is larger than VAL,
7762 it is placed in IDX and false is returned.
7764 If VAL is larger than any CASE_LABEL, n is placed on IDX and false is
7768 find_case_label_index (gswitch
*stmt
, size_t start_idx
, tree val
, size_t *idx
)
7770 size_t n
= gimple_switch_num_labels (stmt
);
7773 /* Find case label for minimum of the value range or the next one.
7774 At each iteration we are searching in [low, high - 1]. */
7776 for (low
= start_idx
, high
= n
; high
!= low
; )
7780 /* Note that i != high, so we never ask for n. */
7781 size_t i
= (high
+ low
) / 2;
7782 t
= gimple_switch_label (stmt
, i
);
7784 /* Cache the result of comparing CASE_LOW and val. */
7785 cmp
= tree_int_cst_compare (CASE_LOW (t
), val
);
7789 /* Ranges cannot be empty. */
7798 if (CASE_HIGH (t
) != NULL
7799 && tree_int_cst_compare (CASE_HIGH (t
), val
) >= 0)
7811 /* Searches the case label vector VEC for the range of CASE_LABELs that is used
7812 for values between MIN and MAX. The first index is placed in MIN_IDX. The
7813 last index is placed in MAX_IDX. If the range of CASE_LABELs is empty
7814 then MAX_IDX < MIN_IDX.
7815 Returns true if the default label is not needed. */
7818 find_case_label_range (gswitch
*stmt
, tree min
, tree max
, size_t *min_idx
,
7822 bool min_take_default
= !find_case_label_index (stmt
, 1, min
, &i
);
7823 bool max_take_default
= !find_case_label_index (stmt
, i
, max
, &j
);
7827 && max_take_default
)
7829 /* Only the default case label reached.
7830 Return an empty range. */
7837 bool take_default
= min_take_default
|| max_take_default
;
7841 if (max_take_default
)
7844 /* If the case label range is continuous, we do not need
7845 the default case label. Verify that. */
7846 high
= CASE_LOW (gimple_switch_label (stmt
, i
));
7847 if (CASE_HIGH (gimple_switch_label (stmt
, i
)))
7848 high
= CASE_HIGH (gimple_switch_label (stmt
, i
));
7849 for (k
= i
+ 1; k
<= j
; ++k
)
7851 low
= CASE_LOW (gimple_switch_label (stmt
, k
));
7852 if (!integer_onep (int_const_binop (MINUS_EXPR
, low
, high
)))
7854 take_default
= true;
7858 if (CASE_HIGH (gimple_switch_label (stmt
, k
)))
7859 high
= CASE_HIGH (gimple_switch_label (stmt
, k
));
7864 return !take_default
;
7868 /* Searches the case label vector VEC for the ranges of CASE_LABELs that are
7869 used in range VR. The indices are placed in MIN_IDX1, MAX_IDX, MIN_IDX2 and
7870 MAX_IDX2. If the ranges of CASE_LABELs are empty then MAX_IDX1 < MIN_IDX1.
7871 Returns true if the default label is not needed. */
7874 find_case_label_ranges (gswitch
*stmt
, value_range
*vr
, size_t *min_idx1
,
7875 size_t *max_idx1
, size_t *min_idx2
,
7879 unsigned int n
= gimple_switch_num_labels (stmt
);
7881 tree case_low
, case_high
;
7882 tree min
= vr
->min
, max
= vr
->max
;
7884 gcc_checking_assert (vr
->type
== VR_RANGE
|| vr
->type
== VR_ANTI_RANGE
);
7886 take_default
= !find_case_label_range (stmt
, min
, max
, &i
, &j
);
7888 /* Set second range to emtpy. */
7892 if (vr
->type
== VR_RANGE
)
7896 return !take_default
;
7899 /* Set first range to all case labels. */
7906 /* Make sure all the values of case labels [i , j] are contained in
7907 range [MIN, MAX]. */
7908 case_low
= CASE_LOW (gimple_switch_label (stmt
, i
));
7909 case_high
= CASE_HIGH (gimple_switch_label (stmt
, j
));
7910 if (tree_int_cst_compare (case_low
, min
) < 0)
7912 if (case_high
!= NULL_TREE
7913 && tree_int_cst_compare (max
, case_high
) < 0)
7919 /* If the range spans case labels [i, j], the corresponding anti-range spans
7920 the labels [1, i - 1] and [j + 1, n - 1]. */
7946 /* Visit switch statement STMT. If we can determine which edge
7947 will be taken out of STMT's basic block, record it in
7948 *TAKEN_EDGE_P. Otherwise, *TAKEN_EDGE_P set to NULL. */
7951 vr_values::vrp_visit_switch_stmt (gswitch
*stmt
, edge
*taken_edge_p
)
7955 size_t i
= 0, j
= 0, k
, l
;
7958 *taken_edge_p
= NULL
;
7959 op
= gimple_switch_index (stmt
);
7960 if (TREE_CODE (op
) != SSA_NAME
)
7963 vr
= get_value_range (op
);
7964 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7966 fprintf (dump_file
, "\nVisiting switch expression with operand ");
7967 print_generic_expr (dump_file
, op
);
7968 fprintf (dump_file
, " with known range ");
7969 dump_value_range (dump_file
, vr
);
7970 fprintf (dump_file
, "\n");
7973 if ((vr
->type
!= VR_RANGE
7974 && vr
->type
!= VR_ANTI_RANGE
)
7975 || symbolic_range_p (vr
))
7978 /* Find the single edge that is taken from the switch expression. */
7979 take_default
= !find_case_label_ranges (stmt
, vr
, &i
, &j
, &k
, &l
);
7981 /* Check if the range spans no CASE_LABEL. If so, we only reach the default
7985 gcc_assert (take_default
);
7986 val
= gimple_switch_default_label (stmt
);
7990 /* Check if labels with index i to j and maybe the default label
7991 are all reaching the same label. */
7993 val
= gimple_switch_label (stmt
, i
);
7995 && CASE_LABEL (gimple_switch_default_label (stmt
))
7996 != CASE_LABEL (val
))
7998 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7999 fprintf (dump_file
, " not a single destination for this "
8003 for (++i
; i
<= j
; ++i
)
8005 if (CASE_LABEL (gimple_switch_label (stmt
, i
)) != CASE_LABEL (val
))
8007 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8008 fprintf (dump_file
, " not a single destination for this "
8015 if (CASE_LABEL (gimple_switch_label (stmt
, k
)) != CASE_LABEL (val
))
8017 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8018 fprintf (dump_file
, " not a single destination for this "
8025 *taken_edge_p
= find_edge (gimple_bb (stmt
),
8026 label_to_block (CASE_LABEL (val
)));
8028 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8030 fprintf (dump_file
, " will take edge to ");
8031 print_generic_stmt (dump_file
, CASE_LABEL (val
));
8036 /* Evaluate statement STMT. If the statement produces a useful range,
8037 set VR and corepsponding OUTPUT_P.
8039 If STMT is a conditional branch and we can determine its truth
8040 value, the taken edge is recorded in *TAKEN_EDGE_P. */
8043 vr_values::extract_range_from_stmt (gimple
*stmt
, edge
*taken_edge_p
,
8044 tree
*output_p
, value_range
*vr
)
8047 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8049 fprintf (dump_file
, "\nVisiting statement:\n");
8050 print_gimple_stmt (dump_file
, stmt
, 0, dump_flags
);
8053 if (!stmt_interesting_for_vrp (stmt
))
8054 gcc_assert (stmt_ends_bb_p (stmt
));
8055 else if (is_gimple_assign (stmt
) || is_gimple_call (stmt
))
8056 vrp_visit_assignment_or_call (stmt
, output_p
, vr
);
8057 else if (gimple_code (stmt
) == GIMPLE_COND
)
8058 vrp_visit_cond_stmt (as_a
<gcond
*> (stmt
), taken_edge_p
);
8059 else if (gimple_code (stmt
) == GIMPLE_SWITCH
)
8060 vrp_visit_switch_stmt (as_a
<gswitch
*> (stmt
), taken_edge_p
);
8063 /* Evaluate statement STMT. If the statement produces a useful range,
8064 return SSA_PROP_INTERESTING and record the SSA name with the
8065 interesting range into *OUTPUT_P.
8067 If STMT is a conditional branch and we can determine its truth
8068 value, the taken edge is recorded in *TAKEN_EDGE_P.
8070 If STMT produces a varying value, return SSA_PROP_VARYING. */
8072 enum ssa_prop_result
8073 vrp_prop::visit_stmt (gimple
*stmt
, edge
*taken_edge_p
, tree
*output_p
)
8075 value_range vr
= VR_INITIALIZER
;
8076 tree lhs
= gimple_get_lhs (stmt
);
8077 extract_range_from_stmt (stmt
, taken_edge_p
, output_p
, &vr
);
8081 if (update_value_range (*output_p
, &vr
))
8083 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8085 fprintf (dump_file
, "Found new range for ");
8086 print_generic_expr (dump_file
, *output_p
);
8087 fprintf (dump_file
, ": ");
8088 dump_value_range (dump_file
, &vr
);
8089 fprintf (dump_file
, "\n");
8092 if (vr
.type
== VR_VARYING
)
8093 return SSA_PROP_VARYING
;
8095 return SSA_PROP_INTERESTING
;
8097 return SSA_PROP_NOT_INTERESTING
;
8100 if (is_gimple_call (stmt
) && gimple_call_internal_p (stmt
))
8101 switch (gimple_call_internal_fn (stmt
))
8103 case IFN_ADD_OVERFLOW
:
8104 case IFN_SUB_OVERFLOW
:
8105 case IFN_MUL_OVERFLOW
:
8106 case IFN_ATOMIC_COMPARE_EXCHANGE
:
8107 /* These internal calls return _Complex integer type,
8108 which VRP does not track, but the immediate uses
8109 thereof might be interesting. */
8110 if (lhs
&& TREE_CODE (lhs
) == SSA_NAME
)
8112 imm_use_iterator iter
;
8113 use_operand_p use_p
;
8114 enum ssa_prop_result res
= SSA_PROP_VARYING
;
8116 set_value_range_to_varying (get_value_range (lhs
));
8118 FOR_EACH_IMM_USE_FAST (use_p
, iter
, lhs
)
8120 gimple
*use_stmt
= USE_STMT (use_p
);
8121 if (!is_gimple_assign (use_stmt
))
8123 enum tree_code rhs_code
= gimple_assign_rhs_code (use_stmt
);
8124 if (rhs_code
!= REALPART_EXPR
&& rhs_code
!= IMAGPART_EXPR
)
8126 tree rhs1
= gimple_assign_rhs1 (use_stmt
);
8127 tree use_lhs
= gimple_assign_lhs (use_stmt
);
8128 if (TREE_CODE (rhs1
) != rhs_code
8129 || TREE_OPERAND (rhs1
, 0) != lhs
8130 || TREE_CODE (use_lhs
) != SSA_NAME
8131 || !stmt_interesting_for_vrp (use_stmt
)
8132 || (!INTEGRAL_TYPE_P (TREE_TYPE (use_lhs
))
8133 || !TYPE_MIN_VALUE (TREE_TYPE (use_lhs
))
8134 || !TYPE_MAX_VALUE (TREE_TYPE (use_lhs
))))
8137 /* If there is a change in the value range for any of the
8138 REALPART_EXPR/IMAGPART_EXPR immediate uses, return
8139 SSA_PROP_INTERESTING. If there are any REALPART_EXPR
8140 or IMAGPART_EXPR immediate uses, but none of them have
8141 a change in their value ranges, return
8142 SSA_PROP_NOT_INTERESTING. If there are no
8143 {REAL,IMAG}PART_EXPR uses at all,
8144 return SSA_PROP_VARYING. */
8145 value_range new_vr
= VR_INITIALIZER
;
8146 extract_range_basic (&new_vr
, use_stmt
);
8147 value_range
*old_vr
= get_value_range (use_lhs
);
8148 if (old_vr
->type
!= new_vr
.type
8149 || !vrp_operand_equal_p (old_vr
->min
, new_vr
.min
)
8150 || !vrp_operand_equal_p (old_vr
->max
, new_vr
.max
)
8151 || !vrp_bitmap_equal_p (old_vr
->equiv
, new_vr
.equiv
))
8152 res
= SSA_PROP_INTERESTING
;
8154 res
= SSA_PROP_NOT_INTERESTING
;
8155 BITMAP_FREE (new_vr
.equiv
);
8156 if (res
== SSA_PROP_INTERESTING
)
8170 /* All other statements produce nothing of interest for VRP, so mark
8171 their outputs varying and prevent further simulation. */
8172 set_defs_to_varying (stmt
);
8174 return (*taken_edge_p
) ? SSA_PROP_INTERESTING
: SSA_PROP_VARYING
;
8177 /* Union the two value-ranges { *VR0TYPE, *VR0MIN, *VR0MAX } and
8178 { VR1TYPE, VR0MIN, VR0MAX } and store the result
8179 in { *VR0TYPE, *VR0MIN, *VR0MAX }. This may not be the smallest
8180 possible such range. The resulting range is not canonicalized. */
8183 union_ranges (enum value_range_type
*vr0type
,
8184 tree
*vr0min
, tree
*vr0max
,
8185 enum value_range_type vr1type
,
8186 tree vr1min
, tree vr1max
)
8188 bool mineq
= vrp_operand_equal_p (*vr0min
, vr1min
);
8189 bool maxeq
= vrp_operand_equal_p (*vr0max
, vr1max
);
8191 /* [] is vr0, () is vr1 in the following classification comments. */
8195 if (*vr0type
== vr1type
)
8196 /* Nothing to do for equal ranges. */
8198 else if ((*vr0type
== VR_RANGE
8199 && vr1type
== VR_ANTI_RANGE
)
8200 || (*vr0type
== VR_ANTI_RANGE
8201 && vr1type
== VR_RANGE
))
8203 /* For anti-range with range union the result is varying. */
8209 else if (operand_less_p (*vr0max
, vr1min
) == 1
8210 || operand_less_p (vr1max
, *vr0min
) == 1)
8212 /* [ ] ( ) or ( ) [ ]
8213 If the ranges have an empty intersection, result of the union
8214 operation is the anti-range or if both are anti-ranges
8216 if (*vr0type
== VR_ANTI_RANGE
8217 && vr1type
== VR_ANTI_RANGE
)
8219 else if (*vr0type
== VR_ANTI_RANGE
8220 && vr1type
== VR_RANGE
)
8222 else if (*vr0type
== VR_RANGE
8223 && vr1type
== VR_ANTI_RANGE
)
8229 else if (*vr0type
== VR_RANGE
8230 && vr1type
== VR_RANGE
)
8232 /* The result is the convex hull of both ranges. */
8233 if (operand_less_p (*vr0max
, vr1min
) == 1)
8235 /* If the result can be an anti-range, create one. */
8236 if (TREE_CODE (*vr0max
) == INTEGER_CST
8237 && TREE_CODE (vr1min
) == INTEGER_CST
8238 && vrp_val_is_min (*vr0min
)
8239 && vrp_val_is_max (vr1max
))
8241 tree min
= int_const_binop (PLUS_EXPR
,
8243 build_int_cst (TREE_TYPE (*vr0max
), 1));
8244 tree max
= int_const_binop (MINUS_EXPR
,
8246 build_int_cst (TREE_TYPE (vr1min
), 1));
8247 if (!operand_less_p (max
, min
))
8249 *vr0type
= VR_ANTI_RANGE
;
8261 /* If the result can be an anti-range, create one. */
8262 if (TREE_CODE (vr1max
) == INTEGER_CST
8263 && TREE_CODE (*vr0min
) == INTEGER_CST
8264 && vrp_val_is_min (vr1min
)
8265 && vrp_val_is_max (*vr0max
))
8267 tree min
= int_const_binop (PLUS_EXPR
,
8269 build_int_cst (TREE_TYPE (vr1max
), 1));
8270 tree max
= int_const_binop (MINUS_EXPR
,
8272 build_int_cst (TREE_TYPE (*vr0min
), 1));
8273 if (!operand_less_p (max
, min
))
8275 *vr0type
= VR_ANTI_RANGE
;
8289 else if ((maxeq
|| operand_less_p (vr1max
, *vr0max
) == 1)
8290 && (mineq
|| operand_less_p (*vr0min
, vr1min
) == 1))
8292 /* [ ( ) ] or [( ) ] or [ ( )] */
8293 if (*vr0type
== VR_RANGE
8294 && vr1type
== VR_RANGE
)
8296 else if (*vr0type
== VR_ANTI_RANGE
8297 && vr1type
== VR_ANTI_RANGE
)
8303 else if (*vr0type
== VR_ANTI_RANGE
8304 && vr1type
== VR_RANGE
)
8306 /* Arbitrarily choose the right or left gap. */
8307 if (!mineq
&& TREE_CODE (vr1min
) == INTEGER_CST
)
8308 *vr0max
= int_const_binop (MINUS_EXPR
, vr1min
,
8309 build_int_cst (TREE_TYPE (vr1min
), 1));
8310 else if (!maxeq
&& TREE_CODE (vr1max
) == INTEGER_CST
)
8311 *vr0min
= int_const_binop (PLUS_EXPR
, vr1max
,
8312 build_int_cst (TREE_TYPE (vr1max
), 1));
8316 else if (*vr0type
== VR_RANGE
8317 && vr1type
== VR_ANTI_RANGE
)
8318 /* The result covers everything. */
8323 else if ((maxeq
|| operand_less_p (*vr0max
, vr1max
) == 1)
8324 && (mineq
|| operand_less_p (vr1min
, *vr0min
) == 1))
8326 /* ( [ ] ) or ([ ] ) or ( [ ]) */
8327 if (*vr0type
== VR_RANGE
8328 && vr1type
== VR_RANGE
)
8334 else if (*vr0type
== VR_ANTI_RANGE
8335 && vr1type
== VR_ANTI_RANGE
)
8337 else if (*vr0type
== VR_RANGE
8338 && vr1type
== VR_ANTI_RANGE
)
8340 *vr0type
= VR_ANTI_RANGE
;
8341 if (!mineq
&& TREE_CODE (*vr0min
) == INTEGER_CST
)
8343 *vr0max
= int_const_binop (MINUS_EXPR
, *vr0min
,
8344 build_int_cst (TREE_TYPE (*vr0min
), 1));
8347 else if (!maxeq
&& TREE_CODE (*vr0max
) == INTEGER_CST
)
8349 *vr0min
= int_const_binop (PLUS_EXPR
, *vr0max
,
8350 build_int_cst (TREE_TYPE (*vr0max
), 1));
8356 else if (*vr0type
== VR_ANTI_RANGE
8357 && vr1type
== VR_RANGE
)
8358 /* The result covers everything. */
8363 else if ((operand_less_p (vr1min
, *vr0max
) == 1
8364 || operand_equal_p (vr1min
, *vr0max
, 0))
8365 && operand_less_p (*vr0min
, vr1min
) == 1
8366 && operand_less_p (*vr0max
, vr1max
) == 1)
8368 /* [ ( ] ) or [ ]( ) */
8369 if (*vr0type
== VR_RANGE
8370 && vr1type
== VR_RANGE
)
8372 else if (*vr0type
== VR_ANTI_RANGE
8373 && vr1type
== VR_ANTI_RANGE
)
8375 else if (*vr0type
== VR_ANTI_RANGE
8376 && vr1type
== VR_RANGE
)
8378 if (TREE_CODE (vr1min
) == INTEGER_CST
)
8379 *vr0max
= int_const_binop (MINUS_EXPR
, vr1min
,
8380 build_int_cst (TREE_TYPE (vr1min
), 1));
8384 else if (*vr0type
== VR_RANGE
8385 && vr1type
== VR_ANTI_RANGE
)
8387 if (TREE_CODE (*vr0max
) == INTEGER_CST
)
8390 *vr0min
= int_const_binop (PLUS_EXPR
, *vr0max
,
8391 build_int_cst (TREE_TYPE (*vr0max
), 1));
8400 else if ((operand_less_p (*vr0min
, vr1max
) == 1
8401 || operand_equal_p (*vr0min
, vr1max
, 0))
8402 && operand_less_p (vr1min
, *vr0min
) == 1
8403 && operand_less_p (vr1max
, *vr0max
) == 1)
8405 /* ( [ ) ] or ( )[ ] */
8406 if (*vr0type
== VR_RANGE
8407 && vr1type
== VR_RANGE
)
8409 else if (*vr0type
== VR_ANTI_RANGE
8410 && vr1type
== VR_ANTI_RANGE
)
8412 else if (*vr0type
== VR_ANTI_RANGE
8413 && vr1type
== VR_RANGE
)
8415 if (TREE_CODE (vr1max
) == INTEGER_CST
)
8416 *vr0min
= int_const_binop (PLUS_EXPR
, vr1max
,
8417 build_int_cst (TREE_TYPE (vr1max
), 1));
8421 else if (*vr0type
== VR_RANGE
8422 && vr1type
== VR_ANTI_RANGE
)
8424 if (TREE_CODE (*vr0min
) == INTEGER_CST
)
8428 *vr0max
= int_const_binop (MINUS_EXPR
, *vr0min
,
8429 build_int_cst (TREE_TYPE (*vr0min
), 1));
8443 *vr0type
= VR_VARYING
;
8444 *vr0min
= NULL_TREE
;
8445 *vr0max
= NULL_TREE
;
8448 /* Intersect the two value-ranges { *VR0TYPE, *VR0MIN, *VR0MAX } and
8449 { VR1TYPE, VR0MIN, VR0MAX } and store the result
8450 in { *VR0TYPE, *VR0MIN, *VR0MAX }. This may not be the smallest
8451 possible such range. The resulting range is not canonicalized. */
8454 intersect_ranges (enum value_range_type
*vr0type
,
8455 tree
*vr0min
, tree
*vr0max
,
8456 enum value_range_type vr1type
,
8457 tree vr1min
, tree vr1max
)
8459 bool mineq
= vrp_operand_equal_p (*vr0min
, vr1min
);
8460 bool maxeq
= vrp_operand_equal_p (*vr0max
, vr1max
);
8462 /* [] is vr0, () is vr1 in the following classification comments. */
8466 if (*vr0type
== vr1type
)
8467 /* Nothing to do for equal ranges. */
8469 else if ((*vr0type
== VR_RANGE
8470 && vr1type
== VR_ANTI_RANGE
)
8471 || (*vr0type
== VR_ANTI_RANGE
8472 && vr1type
== VR_RANGE
))
8474 /* For anti-range with range intersection the result is empty. */
8475 *vr0type
= VR_UNDEFINED
;
8476 *vr0min
= NULL_TREE
;
8477 *vr0max
= NULL_TREE
;
8482 else if (operand_less_p (*vr0max
, vr1min
) == 1
8483 || operand_less_p (vr1max
, *vr0min
) == 1)
8485 /* [ ] ( ) or ( ) [ ]
8486 If the ranges have an empty intersection, the result of the
8487 intersect operation is the range for intersecting an
8488 anti-range with a range or empty when intersecting two ranges. */
8489 if (*vr0type
== VR_RANGE
8490 && vr1type
== VR_ANTI_RANGE
)
8492 else if (*vr0type
== VR_ANTI_RANGE
8493 && vr1type
== VR_RANGE
)
8499 else if (*vr0type
== VR_RANGE
8500 && vr1type
== VR_RANGE
)
8502 *vr0type
= VR_UNDEFINED
;
8503 *vr0min
= NULL_TREE
;
8504 *vr0max
= NULL_TREE
;
8506 else if (*vr0type
== VR_ANTI_RANGE
8507 && vr1type
== VR_ANTI_RANGE
)
8509 /* If the anti-ranges are adjacent to each other merge them. */
8510 if (TREE_CODE (*vr0max
) == INTEGER_CST
8511 && TREE_CODE (vr1min
) == INTEGER_CST
8512 && operand_less_p (*vr0max
, vr1min
) == 1
8513 && integer_onep (int_const_binop (MINUS_EXPR
,
8516 else if (TREE_CODE (vr1max
) == INTEGER_CST
8517 && TREE_CODE (*vr0min
) == INTEGER_CST
8518 && operand_less_p (vr1max
, *vr0min
) == 1
8519 && integer_onep (int_const_binop (MINUS_EXPR
,
8522 /* Else arbitrarily take VR0. */
8525 else if ((maxeq
|| operand_less_p (vr1max
, *vr0max
) == 1)
8526 && (mineq
|| operand_less_p (*vr0min
, vr1min
) == 1))
8528 /* [ ( ) ] or [( ) ] or [ ( )] */
8529 if (*vr0type
== VR_RANGE
8530 && vr1type
== VR_RANGE
)
8532 /* If both are ranges the result is the inner one. */
8537 else if (*vr0type
== VR_RANGE
8538 && vr1type
== VR_ANTI_RANGE
)
8540 /* Choose the right gap if the left one is empty. */
8543 if (TREE_CODE (vr1max
) != INTEGER_CST
)
8545 else if (TYPE_PRECISION (TREE_TYPE (vr1max
)) == 1
8546 && !TYPE_UNSIGNED (TREE_TYPE (vr1max
)))
8548 = int_const_binop (MINUS_EXPR
, vr1max
,
8549 build_int_cst (TREE_TYPE (vr1max
), -1));
8552 = int_const_binop (PLUS_EXPR
, vr1max
,
8553 build_int_cst (TREE_TYPE (vr1max
), 1));
8555 /* Choose the left gap if the right one is empty. */
8558 if (TREE_CODE (vr1min
) != INTEGER_CST
)
8560 else if (TYPE_PRECISION (TREE_TYPE (vr1min
)) == 1
8561 && !TYPE_UNSIGNED (TREE_TYPE (vr1min
)))
8563 = int_const_binop (PLUS_EXPR
, vr1min
,
8564 build_int_cst (TREE_TYPE (vr1min
), -1));
8567 = int_const_binop (MINUS_EXPR
, vr1min
,
8568 build_int_cst (TREE_TYPE (vr1min
), 1));
8570 /* Choose the anti-range if the range is effectively varying. */
8571 else if (vrp_val_is_min (*vr0min
)
8572 && vrp_val_is_max (*vr0max
))
8578 /* Else choose the range. */
8580 else if (*vr0type
== VR_ANTI_RANGE
8581 && vr1type
== VR_ANTI_RANGE
)
8582 /* If both are anti-ranges the result is the outer one. */
8584 else if (*vr0type
== VR_ANTI_RANGE
8585 && vr1type
== VR_RANGE
)
8587 /* The intersection is empty. */
8588 *vr0type
= VR_UNDEFINED
;
8589 *vr0min
= NULL_TREE
;
8590 *vr0max
= NULL_TREE
;
8595 else if ((maxeq
|| operand_less_p (*vr0max
, vr1max
) == 1)
8596 && (mineq
|| operand_less_p (vr1min
, *vr0min
) == 1))
8598 /* ( [ ] ) or ([ ] ) or ( [ ]) */
8599 if (*vr0type
== VR_RANGE
8600 && vr1type
== VR_RANGE
)
8601 /* Choose the inner range. */
8603 else if (*vr0type
== VR_ANTI_RANGE
8604 && vr1type
== VR_RANGE
)
8606 /* Choose the right gap if the left is empty. */
8609 *vr0type
= VR_RANGE
;
8610 if (TREE_CODE (*vr0max
) != INTEGER_CST
)
8612 else if (TYPE_PRECISION (TREE_TYPE (*vr0max
)) == 1
8613 && !TYPE_UNSIGNED (TREE_TYPE (*vr0max
)))
8615 = int_const_binop (MINUS_EXPR
, *vr0max
,
8616 build_int_cst (TREE_TYPE (*vr0max
), -1));
8619 = int_const_binop (PLUS_EXPR
, *vr0max
,
8620 build_int_cst (TREE_TYPE (*vr0max
), 1));
8623 /* Choose the left gap if the right is empty. */
8626 *vr0type
= VR_RANGE
;
8627 if (TREE_CODE (*vr0min
) != INTEGER_CST
)
8629 else if (TYPE_PRECISION (TREE_TYPE (*vr0min
)) == 1
8630 && !TYPE_UNSIGNED (TREE_TYPE (*vr0min
)))
8632 = int_const_binop (PLUS_EXPR
, *vr0min
,
8633 build_int_cst (TREE_TYPE (*vr0min
), -1));
8636 = int_const_binop (MINUS_EXPR
, *vr0min
,
8637 build_int_cst (TREE_TYPE (*vr0min
), 1));
8640 /* Choose the anti-range if the range is effectively varying. */
8641 else if (vrp_val_is_min (vr1min
)
8642 && vrp_val_is_max (vr1max
))
8644 /* Choose the anti-range if it is ~[0,0], that range is special
8645 enough to special case when vr1's range is relatively wide. */
8646 else if (*vr0min
== *vr0max
8647 && integer_zerop (*vr0min
)
8648 && (TYPE_PRECISION (TREE_TYPE (*vr0min
))
8649 == TYPE_PRECISION (ptr_type_node
))
8650 && TREE_CODE (vr1max
) == INTEGER_CST
8651 && TREE_CODE (vr1min
) == INTEGER_CST
8652 && (wi::clz (wi::to_wide (vr1max
) - wi::to_wide (vr1min
))
8653 < TYPE_PRECISION (TREE_TYPE (*vr0min
)) / 2))
8655 /* Else choose the range. */
8663 else if (*vr0type
== VR_ANTI_RANGE
8664 && vr1type
== VR_ANTI_RANGE
)
8666 /* If both are anti-ranges the result is the outer one. */
8671 else if (vr1type
== VR_ANTI_RANGE
8672 && *vr0type
== VR_RANGE
)
8674 /* The intersection is empty. */
8675 *vr0type
= VR_UNDEFINED
;
8676 *vr0min
= NULL_TREE
;
8677 *vr0max
= NULL_TREE
;
8682 else if ((operand_less_p (vr1min
, *vr0max
) == 1
8683 || operand_equal_p (vr1min
, *vr0max
, 0))
8684 && operand_less_p (*vr0min
, vr1min
) == 1)
8686 /* [ ( ] ) or [ ]( ) */
8687 if (*vr0type
== VR_ANTI_RANGE
8688 && vr1type
== VR_ANTI_RANGE
)
8690 else if (*vr0type
== VR_RANGE
8691 && vr1type
== VR_RANGE
)
8693 else if (*vr0type
== VR_RANGE
8694 && vr1type
== VR_ANTI_RANGE
)
8696 if (TREE_CODE (vr1min
) == INTEGER_CST
)
8697 *vr0max
= int_const_binop (MINUS_EXPR
, vr1min
,
8698 build_int_cst (TREE_TYPE (vr1min
), 1));
8702 else if (*vr0type
== VR_ANTI_RANGE
8703 && vr1type
== VR_RANGE
)
8705 *vr0type
= VR_RANGE
;
8706 if (TREE_CODE (*vr0max
) == INTEGER_CST
)
8707 *vr0min
= int_const_binop (PLUS_EXPR
, *vr0max
,
8708 build_int_cst (TREE_TYPE (*vr0max
), 1));
8716 else if ((operand_less_p (*vr0min
, vr1max
) == 1
8717 || operand_equal_p (*vr0min
, vr1max
, 0))
8718 && operand_less_p (vr1min
, *vr0min
) == 1)
8720 /* ( [ ) ] or ( )[ ] */
8721 if (*vr0type
== VR_ANTI_RANGE
8722 && vr1type
== VR_ANTI_RANGE
)
8724 else if (*vr0type
== VR_RANGE
8725 && vr1type
== VR_RANGE
)
8727 else if (*vr0type
== VR_RANGE
8728 && vr1type
== VR_ANTI_RANGE
)
8730 if (TREE_CODE (vr1max
) == INTEGER_CST
)
8731 *vr0min
= int_const_binop (PLUS_EXPR
, vr1max
,
8732 build_int_cst (TREE_TYPE (vr1max
), 1));
8736 else if (*vr0type
== VR_ANTI_RANGE
8737 && vr1type
== VR_RANGE
)
8739 *vr0type
= VR_RANGE
;
8740 if (TREE_CODE (*vr0min
) == INTEGER_CST
)
8741 *vr0max
= int_const_binop (MINUS_EXPR
, *vr0min
,
8742 build_int_cst (TREE_TYPE (*vr0min
), 1));
8751 /* As a fallback simply use { *VRTYPE, *VR0MIN, *VR0MAX } as
8752 result for the intersection. That's always a conservative
8753 correct estimate unless VR1 is a constant singleton range
8754 in which case we choose that. */
8755 if (vr1type
== VR_RANGE
8756 && is_gimple_min_invariant (vr1min
)
8757 && vrp_operand_equal_p (vr1min
, vr1max
))
8768 /* Intersect the two value-ranges *VR0 and *VR1 and store the result
8769 in *VR0. This may not be the smallest possible such range. */
8772 vrp_intersect_ranges_1 (value_range
*vr0
, value_range
*vr1
)
8776 /* If either range is VR_VARYING the other one wins. */
8777 if (vr1
->type
== VR_VARYING
)
8779 if (vr0
->type
== VR_VARYING
)
8781 copy_value_range (vr0
, vr1
);
8785 /* When either range is VR_UNDEFINED the resulting range is
8786 VR_UNDEFINED, too. */
8787 if (vr0
->type
== VR_UNDEFINED
)
8789 if (vr1
->type
== VR_UNDEFINED
)
8791 set_value_range_to_undefined (vr0
);
8795 /* Save the original vr0 so we can return it as conservative intersection
8796 result when our worker turns things to varying. */
8798 intersect_ranges (&vr0
->type
, &vr0
->min
, &vr0
->max
,
8799 vr1
->type
, vr1
->min
, vr1
->max
);
8800 /* Make sure to canonicalize the result though as the inversion of a
8801 VR_RANGE can still be a VR_RANGE. */
8802 set_and_canonicalize_value_range (vr0
, vr0
->type
,
8803 vr0
->min
, vr0
->max
, vr0
->equiv
);
8804 /* If that failed, use the saved original VR0. */
8805 if (vr0
->type
== VR_VARYING
)
8810 /* If the result is VR_UNDEFINED there is no need to mess with
8811 the equivalencies. */
8812 if (vr0
->type
== VR_UNDEFINED
)
8815 /* The resulting set of equivalences for range intersection is the union of
8817 if (vr0
->equiv
&& vr1
->equiv
&& vr0
->equiv
!= vr1
->equiv
)
8818 bitmap_ior_into (vr0
->equiv
, vr1
->equiv
);
8819 else if (vr1
->equiv
&& !vr0
->equiv
)
8821 /* All equivalence bitmaps are allocated from the same obstack. So
8822 we can use the obstack associated with VR to allocate vr0->equiv. */
8823 vr0
->equiv
= BITMAP_ALLOC (vr1
->equiv
->obstack
);
8824 bitmap_copy (vr0
->equiv
, vr1
->equiv
);
8829 vrp_intersect_ranges (value_range
*vr0
, value_range
*vr1
)
8831 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8833 fprintf (dump_file
, "Intersecting\n ");
8834 dump_value_range (dump_file
, vr0
);
8835 fprintf (dump_file
, "\nand\n ");
8836 dump_value_range (dump_file
, vr1
);
8837 fprintf (dump_file
, "\n");
8839 vrp_intersect_ranges_1 (vr0
, vr1
);
8840 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8842 fprintf (dump_file
, "to\n ");
8843 dump_value_range (dump_file
, vr0
);
8844 fprintf (dump_file
, "\n");
8848 /* Meet operation for value ranges. Given two value ranges VR0 and
8849 VR1, store in VR0 a range that contains both VR0 and VR1. This
8850 may not be the smallest possible such range. */
8853 vrp_meet_1 (value_range
*vr0
, const value_range
*vr1
)
8857 if (vr0
->type
== VR_UNDEFINED
)
8859 set_value_range (vr0
, vr1
->type
, vr1
->min
, vr1
->max
, vr1
->equiv
);
8863 if (vr1
->type
== VR_UNDEFINED
)
8865 /* VR0 already has the resulting range. */
8869 if (vr0
->type
== VR_VARYING
)
8871 /* Nothing to do. VR0 already has the resulting range. */
8875 if (vr1
->type
== VR_VARYING
)
8877 set_value_range_to_varying (vr0
);
8882 union_ranges (&vr0
->type
, &vr0
->min
, &vr0
->max
,
8883 vr1
->type
, vr1
->min
, vr1
->max
);
8884 if (vr0
->type
== VR_VARYING
)
8886 /* Failed to find an efficient meet. Before giving up and setting
8887 the result to VARYING, see if we can at least derive a useful
8888 anti-range. FIXME, all this nonsense about distinguishing
8889 anti-ranges from ranges is necessary because of the odd
8890 semantics of range_includes_zero_p and friends. */
8891 if (((saved
.type
== VR_RANGE
8892 && range_includes_zero_p (saved
.min
, saved
.max
) == 0)
8893 || (saved
.type
== VR_ANTI_RANGE
8894 && range_includes_zero_p (saved
.min
, saved
.max
) == 1))
8895 && ((vr1
->type
== VR_RANGE
8896 && range_includes_zero_p (vr1
->min
, vr1
->max
) == 0)
8897 || (vr1
->type
== VR_ANTI_RANGE
8898 && range_includes_zero_p (vr1
->min
, vr1
->max
) == 1)))
8900 set_value_range_to_nonnull (vr0
, TREE_TYPE (saved
.min
));
8902 /* Since this meet operation did not result from the meeting of
8903 two equivalent names, VR0 cannot have any equivalences. */
8905 bitmap_clear (vr0
->equiv
);
8909 set_value_range_to_varying (vr0
);
8912 set_and_canonicalize_value_range (vr0
, vr0
->type
, vr0
->min
, vr0
->max
,
8914 if (vr0
->type
== VR_VARYING
)
8917 /* The resulting set of equivalences is always the intersection of
8919 if (vr0
->equiv
&& vr1
->equiv
&& vr0
->equiv
!= vr1
->equiv
)
8920 bitmap_and_into (vr0
->equiv
, vr1
->equiv
);
8921 else if (vr0
->equiv
&& !vr1
->equiv
)
8922 bitmap_clear (vr0
->equiv
);
8926 vrp_meet (value_range
*vr0
, const value_range
*vr1
)
8928 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8930 fprintf (dump_file
, "Meeting\n ");
8931 dump_value_range (dump_file
, vr0
);
8932 fprintf (dump_file
, "\nand\n ");
8933 dump_value_range (dump_file
, vr1
);
8934 fprintf (dump_file
, "\n");
8936 vrp_meet_1 (vr0
, vr1
);
8937 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8939 fprintf (dump_file
, "to\n ");
8940 dump_value_range (dump_file
, vr0
);
8941 fprintf (dump_file
, "\n");
8946 /* Visit all arguments for PHI node PHI that flow through executable
8947 edges. If a valid value range can be derived from all the incoming
8948 value ranges, set a new range in VR_RESULT. */
8951 vr_values::extract_range_from_phi_node (gphi
*phi
, value_range
*vr_result
)
8954 tree lhs
= PHI_RESULT (phi
);
8955 value_range
*lhs_vr
= get_value_range (lhs
);
8957 int edges
, old_edges
;
8960 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8962 fprintf (dump_file
, "\nVisiting PHI node: ");
8963 print_gimple_stmt (dump_file
, phi
, 0, dump_flags
);
8966 bool may_simulate_backedge_again
= false;
8968 for (i
= 0; i
< gimple_phi_num_args (phi
); i
++)
8970 edge e
= gimple_phi_arg_edge (phi
, i
);
8972 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8975 " Argument #%d (%d -> %d %sexecutable)\n",
8976 (int) i
, e
->src
->index
, e
->dest
->index
,
8977 (e
->flags
& EDGE_EXECUTABLE
) ? "" : "not ");
8980 if (e
->flags
& EDGE_EXECUTABLE
)
8982 tree arg
= PHI_ARG_DEF (phi
, i
);
8987 if (TREE_CODE (arg
) == SSA_NAME
)
8989 /* See if we are eventually going to change one of the args. */
8990 gimple
*def_stmt
= SSA_NAME_DEF_STMT (arg
);
8991 if (! gimple_nop_p (def_stmt
)
8992 && prop_simulate_again_p (def_stmt
)
8993 && e
->flags
& EDGE_DFS_BACK
)
8994 may_simulate_backedge_again
= true;
8996 vr_arg
= *(get_value_range (arg
));
8997 /* Do not allow equivalences or symbolic ranges to leak in from
8998 backedges. That creates invalid equivalencies.
8999 See PR53465 and PR54767. */
9000 if (e
->flags
& EDGE_DFS_BACK
)
9002 if (vr_arg
.type
== VR_RANGE
9003 || vr_arg
.type
== VR_ANTI_RANGE
)
9005 vr_arg
.equiv
= NULL
;
9006 if (symbolic_range_p (&vr_arg
))
9008 vr_arg
.type
= VR_VARYING
;
9009 vr_arg
.min
= NULL_TREE
;
9010 vr_arg
.max
= NULL_TREE
;
9016 /* If the non-backedge arguments range is VR_VARYING then
9017 we can still try recording a simple equivalence. */
9018 if (vr_arg
.type
== VR_VARYING
)
9020 vr_arg
.type
= VR_RANGE
;
9023 vr_arg
.equiv
= NULL
;
9029 if (TREE_OVERFLOW_P (arg
))
9030 arg
= drop_tree_overflow (arg
);
9032 vr_arg
.type
= VR_RANGE
;
9035 vr_arg
.equiv
= NULL
;
9038 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
9040 fprintf (dump_file
, "\t");
9041 print_generic_expr (dump_file
, arg
, dump_flags
);
9042 fprintf (dump_file
, ": ");
9043 dump_value_range (dump_file
, &vr_arg
);
9044 fprintf (dump_file
, "\n");
9048 copy_value_range (vr_result
, &vr_arg
);
9050 vrp_meet (vr_result
, &vr_arg
);
9053 if (vr_result
->type
== VR_VARYING
)
9058 if (vr_result
->type
== VR_VARYING
)
9060 else if (vr_result
->type
== VR_UNDEFINED
)
9063 old_edges
= vr_phi_edge_counts
[SSA_NAME_VERSION (lhs
)];
9064 vr_phi_edge_counts
[SSA_NAME_VERSION (lhs
)] = edges
;
9066 /* To prevent infinite iterations in the algorithm, derive ranges
9067 when the new value is slightly bigger or smaller than the
9068 previous one. We don't do this if we have seen a new executable
9069 edge; this helps us avoid an infinity for conditionals
9070 which are not in a loop. If the old value-range was VR_UNDEFINED
9071 use the updated range and iterate one more time. If we will not
9072 simulate this PHI again via the backedge allow us to iterate. */
9074 && gimple_phi_num_args (phi
) > 1
9075 && edges
== old_edges
9076 && lhs_vr
->type
!= VR_UNDEFINED
9077 && may_simulate_backedge_again
)
9079 /* Compare old and new ranges, fall back to varying if the
9080 values are not comparable. */
9081 int cmp_min
= compare_values (lhs_vr
->min
, vr_result
->min
);
9084 int cmp_max
= compare_values (lhs_vr
->max
, vr_result
->max
);
9088 /* For non VR_RANGE or for pointers fall back to varying if
9089 the range changed. */
9090 if ((lhs_vr
->type
!= VR_RANGE
|| vr_result
->type
!= VR_RANGE
9091 || POINTER_TYPE_P (TREE_TYPE (lhs
)))
9092 && (cmp_min
!= 0 || cmp_max
!= 0))
9095 /* If the new minimum is larger than the previous one
9096 retain the old value. If the new minimum value is smaller
9097 than the previous one and not -INF go all the way to -INF + 1.
9098 In the first case, to avoid infinite bouncing between different
9099 minimums, and in the other case to avoid iterating millions of
9100 times to reach -INF. Going to -INF + 1 also lets the following
9101 iteration compute whether there will be any overflow, at the
9102 expense of one additional iteration. */
9104 vr_result
->min
= lhs_vr
->min
;
9105 else if (cmp_min
> 0
9106 && !vrp_val_is_min (vr_result
->min
))
9108 = int_const_binop (PLUS_EXPR
,
9109 vrp_val_min (TREE_TYPE (vr_result
->min
)),
9110 build_int_cst (TREE_TYPE (vr_result
->min
), 1));
9112 /* Similarly for the maximum value. */
9114 vr_result
->max
= lhs_vr
->max
;
9115 else if (cmp_max
< 0
9116 && !vrp_val_is_max (vr_result
->max
))
9118 = int_const_binop (MINUS_EXPR
,
9119 vrp_val_max (TREE_TYPE (vr_result
->min
)),
9120 build_int_cst (TREE_TYPE (vr_result
->min
), 1));
9122 /* If we dropped either bound to +-INF then if this is a loop
9123 PHI node SCEV may known more about its value-range. */
9124 if (cmp_min
> 0 || cmp_min
< 0
9125 || cmp_max
< 0 || cmp_max
> 0)
9128 goto infinite_check
;
9134 set_value_range_to_varying (vr_result
);
9137 /* If this is a loop PHI node SCEV may known more about its value-range.
9138 scev_check can be reached from two paths, one is a fall through from above
9139 "varying" label, the other is direct goto from code block which tries to
9140 avoid infinite simulation. */
9141 if ((l
= loop_containing_stmt (phi
))
9142 && l
->header
== gimple_bb (phi
))
9143 adjust_range_with_scev (vr_result
, l
, phi
, lhs
);
9146 /* If we will end up with a (-INF, +INF) range, set it to
9147 VARYING. Same if the previous max value was invalid for
9148 the type and we end up with vr_result.min > vr_result.max. */
9149 if ((vr_result
->type
== VR_RANGE
|| vr_result
->type
== VR_ANTI_RANGE
)
9150 && !((vrp_val_is_max (vr_result
->max
) && vrp_val_is_min (vr_result
->min
))
9151 || compare_values (vr_result
->min
, vr_result
->max
) > 0))
9154 set_value_range_to_varying (vr_result
);
9156 /* If the new range is different than the previous value, keep
9162 /* Visit all arguments for PHI node PHI that flow through executable
9163 edges. If a valid value range can be derived from all the incoming
9164 value ranges, set a new range for the LHS of PHI. */
9166 enum ssa_prop_result
9167 vrp_prop::visit_phi (gphi
*phi
)
9169 tree lhs
= PHI_RESULT (phi
);
9170 value_range vr_result
= VR_INITIALIZER
;
9171 extract_range_from_phi_node (phi
, &vr_result
);
9172 if (update_value_range (lhs
, &vr_result
))
9174 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
9176 fprintf (dump_file
, "Found new range for ");
9177 print_generic_expr (dump_file
, lhs
);
9178 fprintf (dump_file
, ": ");
9179 dump_value_range (dump_file
, &vr_result
);
9180 fprintf (dump_file
, "\n");
9183 if (vr_result
.type
== VR_VARYING
)
9184 return SSA_PROP_VARYING
;
9186 return SSA_PROP_INTERESTING
;
9189 /* Nothing changed, don't add outgoing edges. */
9190 return SSA_PROP_NOT_INTERESTING
;
9193 /* Simplify boolean operations if the source is known
9194 to be already a boolean. */
9196 vr_values::simplify_truth_ops_using_ranges (gimple_stmt_iterator
*gsi
,
9199 enum tree_code rhs_code
= gimple_assign_rhs_code (stmt
);
9201 bool need_conversion
;
9203 /* We handle only !=/== case here. */
9204 gcc_assert (rhs_code
== EQ_EXPR
|| rhs_code
== NE_EXPR
);
9206 op0
= gimple_assign_rhs1 (stmt
);
9207 if (!op_with_boolean_value_range_p (op0
))
9210 op1
= gimple_assign_rhs2 (stmt
);
9211 if (!op_with_boolean_value_range_p (op1
))
9214 /* Reduce number of cases to handle to NE_EXPR. As there is no
9215 BIT_XNOR_EXPR we cannot replace A == B with a single statement. */
9216 if (rhs_code
== EQ_EXPR
)
9218 if (TREE_CODE (op1
) == INTEGER_CST
)
9219 op1
= int_const_binop (BIT_XOR_EXPR
, op1
,
9220 build_int_cst (TREE_TYPE (op1
), 1));
9225 lhs
= gimple_assign_lhs (stmt
);
9227 = !useless_type_conversion_p (TREE_TYPE (lhs
), TREE_TYPE (op0
));
9229 /* Make sure to not sign-extend a 1-bit 1 when converting the result. */
9231 && !TYPE_UNSIGNED (TREE_TYPE (op0
))
9232 && TYPE_PRECISION (TREE_TYPE (op0
)) == 1
9233 && TYPE_PRECISION (TREE_TYPE (lhs
)) > 1)
9236 /* For A != 0 we can substitute A itself. */
9237 if (integer_zerop (op1
))
9238 gimple_assign_set_rhs_with_ops (gsi
,
9240 ? NOP_EXPR
: TREE_CODE (op0
), op0
);
9241 /* For A != B we substitute A ^ B. Either with conversion. */
9242 else if (need_conversion
)
9244 tree tem
= make_ssa_name (TREE_TYPE (op0
));
9246 = gimple_build_assign (tem
, BIT_XOR_EXPR
, op0
, op1
);
9247 gsi_insert_before (gsi
, newop
, GSI_SAME_STMT
);
9248 if (INTEGRAL_TYPE_P (TREE_TYPE (tem
))
9249 && TYPE_PRECISION (TREE_TYPE (tem
)) > 1)
9250 set_range_info (tem
, VR_RANGE
,
9251 wi::zero (TYPE_PRECISION (TREE_TYPE (tem
))),
9252 wi::one (TYPE_PRECISION (TREE_TYPE (tem
))));
9253 gimple_assign_set_rhs_with_ops (gsi
, NOP_EXPR
, tem
);
9257 gimple_assign_set_rhs_with_ops (gsi
, BIT_XOR_EXPR
, op0
, op1
);
9258 update_stmt (gsi_stmt (*gsi
));
9259 fold_stmt (gsi
, follow_single_use_edges
);
9264 /* Simplify a division or modulo operator to a right shift or bitwise and
9265 if the first operand is unsigned or is greater than zero and the second
9266 operand is an exact power of two. For TRUNC_MOD_EXPR op0 % op1 with
9267 constant op1 (op1min = op1) or with op1 in [op1min, op1max] range,
9268 optimize it into just op0 if op0's range is known to be a subset of
9269 [-op1min + 1, op1min - 1] for signed and [0, op1min - 1] for unsigned
9273 vr_values::simplify_div_or_mod_using_ranges (gimple_stmt_iterator
*gsi
,
9276 enum tree_code rhs_code
= gimple_assign_rhs_code (stmt
);
9278 tree op0
= gimple_assign_rhs1 (stmt
);
9279 tree op1
= gimple_assign_rhs2 (stmt
);
9280 tree op0min
= NULL_TREE
, op0max
= NULL_TREE
;
9282 value_range
*vr
= NULL
;
9284 if (TREE_CODE (op0
) == INTEGER_CST
)
9291 vr
= get_value_range (op0
);
9292 if (range_int_cst_p (vr
))
9299 if (rhs_code
== TRUNC_MOD_EXPR
9300 && TREE_CODE (op1
) == SSA_NAME
)
9302 value_range
*vr1
= get_value_range (op1
);
9303 if (range_int_cst_p (vr1
))
9306 if (rhs_code
== TRUNC_MOD_EXPR
9307 && TREE_CODE (op1min
) == INTEGER_CST
9308 && tree_int_cst_sgn (op1min
) == 1
9310 && tree_int_cst_lt (op0max
, op1min
))
9312 if (TYPE_UNSIGNED (TREE_TYPE (op0
))
9313 || tree_int_cst_sgn (op0min
) >= 0
9314 || tree_int_cst_lt (fold_unary (NEGATE_EXPR
, TREE_TYPE (op1min
), op1min
),
9317 /* If op0 already has the range op0 % op1 has,
9318 then TRUNC_MOD_EXPR won't change anything. */
9319 gimple_assign_set_rhs_from_tree (gsi
, op0
);
9324 if (TREE_CODE (op0
) != SSA_NAME
)
9327 if (!integer_pow2p (op1
))
9329 /* X % -Y can be only optimized into X % Y either if
9330 X is not INT_MIN, or Y is not -1. Fold it now, as after
9331 remove_range_assertions the range info might be not available
9333 if (rhs_code
== TRUNC_MOD_EXPR
9334 && fold_stmt (gsi
, follow_single_use_edges
))
9339 if (TYPE_UNSIGNED (TREE_TYPE (op0
)))
9340 val
= integer_one_node
;
9345 val
= compare_range_with_value (GE_EXPR
, vr
, integer_zero_node
, &sop
);
9349 && integer_onep (val
)
9350 && issue_strict_overflow_warning (WARN_STRICT_OVERFLOW_MISC
))
9352 location_t location
;
9354 if (!gimple_has_location (stmt
))
9355 location
= input_location
;
9357 location
= gimple_location (stmt
);
9358 warning_at (location
, OPT_Wstrict_overflow
,
9359 "assuming signed overflow does not occur when "
9360 "simplifying %</%> or %<%%%> to %<>>%> or %<&%>");
9364 if (val
&& integer_onep (val
))
9368 if (rhs_code
== TRUNC_DIV_EXPR
)
9370 t
= build_int_cst (integer_type_node
, tree_log2 (op1
));
9371 gimple_assign_set_rhs_code (stmt
, RSHIFT_EXPR
);
9372 gimple_assign_set_rhs1 (stmt
, op0
);
9373 gimple_assign_set_rhs2 (stmt
, t
);
9377 t
= build_int_cst (TREE_TYPE (op1
), 1);
9378 t
= int_const_binop (MINUS_EXPR
, op1
, t
);
9379 t
= fold_convert (TREE_TYPE (op0
), t
);
9381 gimple_assign_set_rhs_code (stmt
, BIT_AND_EXPR
);
9382 gimple_assign_set_rhs1 (stmt
, op0
);
9383 gimple_assign_set_rhs2 (stmt
, t
);
9387 fold_stmt (gsi
, follow_single_use_edges
);
9394 /* Simplify a min or max if the ranges of the two operands are
9395 disjoint. Return true if we do simplify. */
9398 vr_values::simplify_min_or_max_using_ranges (gimple_stmt_iterator
*gsi
,
9401 tree op0
= gimple_assign_rhs1 (stmt
);
9402 tree op1
= gimple_assign_rhs2 (stmt
);
9406 val
= (vrp_evaluate_conditional_warnv_with_ops_using_ranges
9407 (LE_EXPR
, op0
, op1
, &sop
));
9411 val
= (vrp_evaluate_conditional_warnv_with_ops_using_ranges
9412 (LT_EXPR
, op0
, op1
, &sop
));
9417 if (sop
&& issue_strict_overflow_warning (WARN_STRICT_OVERFLOW_MISC
))
9419 location_t location
;
9421 if (!gimple_has_location (stmt
))
9422 location
= input_location
;
9424 location
= gimple_location (stmt
);
9425 warning_at (location
, OPT_Wstrict_overflow
,
9426 "assuming signed overflow does not occur when "
9427 "simplifying %<min/max (X,Y)%> to %<X%> or %<Y%>");
9430 /* VAL == TRUE -> OP0 < or <= op1
9431 VAL == FALSE -> OP0 > or >= op1. */
9432 tree res
= ((gimple_assign_rhs_code (stmt
) == MAX_EXPR
)
9433 == integer_zerop (val
)) ? op0
: op1
;
9434 gimple_assign_set_rhs_from_tree (gsi
, res
);
9441 /* If the operand to an ABS_EXPR is >= 0, then eliminate the
9442 ABS_EXPR. If the operand is <= 0, then simplify the
9443 ABS_EXPR into a NEGATE_EXPR. */
9446 vr_values::simplify_abs_using_ranges (gimple_stmt_iterator
*gsi
, gimple
*stmt
)
9448 tree op
= gimple_assign_rhs1 (stmt
);
9449 value_range
*vr
= get_value_range (op
);
9456 val
= compare_range_with_value (LE_EXPR
, vr
, integer_zero_node
, &sop
);
9459 /* The range is neither <= 0 nor > 0. Now see if it is
9460 either < 0 or >= 0. */
9462 val
= compare_range_with_value (LT_EXPR
, vr
, integer_zero_node
,
9468 if (sop
&& issue_strict_overflow_warning (WARN_STRICT_OVERFLOW_MISC
))
9470 location_t location
;
9472 if (!gimple_has_location (stmt
))
9473 location
= input_location
;
9475 location
= gimple_location (stmt
);
9476 warning_at (location
, OPT_Wstrict_overflow
,
9477 "assuming signed overflow does not occur when "
9478 "simplifying %<abs (X)%> to %<X%> or %<-X%>");
9481 gimple_assign_set_rhs1 (stmt
, op
);
9482 if (integer_zerop (val
))
9483 gimple_assign_set_rhs_code (stmt
, SSA_NAME
);
9485 gimple_assign_set_rhs_code (stmt
, NEGATE_EXPR
);
9487 fold_stmt (gsi
, follow_single_use_edges
);
9495 /* Optimize away redundant BIT_AND_EXPR and BIT_IOR_EXPR.
9496 If all the bits that are being cleared by & are already
9497 known to be zero from VR, or all the bits that are being
9498 set by | are already known to be one from VR, the bit
9499 operation is redundant. */
9502 vr_values::simplify_bit_ops_using_ranges (gimple_stmt_iterator
*gsi
,
9505 tree op0
= gimple_assign_rhs1 (stmt
);
9506 tree op1
= gimple_assign_rhs2 (stmt
);
9507 tree op
= NULL_TREE
;
9508 value_range vr0
= VR_INITIALIZER
;
9509 value_range vr1
= VR_INITIALIZER
;
9510 wide_int may_be_nonzero0
, may_be_nonzero1
;
9511 wide_int must_be_nonzero0
, must_be_nonzero1
;
9514 if (TREE_CODE (op0
) == SSA_NAME
)
9515 vr0
= *(get_value_range (op0
));
9516 else if (is_gimple_min_invariant (op0
))
9517 set_value_range_to_value (&vr0
, op0
, NULL
);
9521 if (TREE_CODE (op1
) == SSA_NAME
)
9522 vr1
= *(get_value_range (op1
));
9523 else if (is_gimple_min_invariant (op1
))
9524 set_value_range_to_value (&vr1
, op1
, NULL
);
9528 if (!zero_nonzero_bits_from_vr (TREE_TYPE (op0
), &vr0
, &may_be_nonzero0
,
9531 if (!zero_nonzero_bits_from_vr (TREE_TYPE (op1
), &vr1
, &may_be_nonzero1
,
9535 switch (gimple_assign_rhs_code (stmt
))
9538 mask
= wi::bit_and_not (may_be_nonzero0
, must_be_nonzero1
);
9544 mask
= wi::bit_and_not (may_be_nonzero1
, must_be_nonzero0
);
9552 mask
= wi::bit_and_not (may_be_nonzero0
, must_be_nonzero1
);
9558 mask
= wi::bit_and_not (may_be_nonzero1
, must_be_nonzero0
);
9569 if (op
== NULL_TREE
)
9572 gimple_assign_set_rhs_with_ops (gsi
, TREE_CODE (op
), op
);
9573 update_stmt (gsi_stmt (*gsi
));
9577 /* We are comparing trees OP0 and OP1 using COND_CODE. OP0 has
9578 a known value range VR.
9580 If there is one and only one value which will satisfy the
9581 conditional, then return that value. Else return NULL.
9583 If signed overflow must be undefined for the value to satisfy
9584 the conditional, then set *STRICT_OVERFLOW_P to true. */
9587 test_for_singularity (enum tree_code cond_code
, tree op0
,
9588 tree op1
, value_range
*vr
)
9593 /* Extract minimum/maximum values which satisfy the conditional as it was
9595 if (cond_code
== LE_EXPR
|| cond_code
== LT_EXPR
)
9597 min
= TYPE_MIN_VALUE (TREE_TYPE (op0
));
9600 if (cond_code
== LT_EXPR
)
9602 tree one
= build_int_cst (TREE_TYPE (op0
), 1);
9603 max
= fold_build2 (MINUS_EXPR
, TREE_TYPE (op0
), max
, one
);
9604 /* Signal to compare_values_warnv this expr doesn't overflow. */
9606 TREE_NO_WARNING (max
) = 1;
9609 else if (cond_code
== GE_EXPR
|| cond_code
== GT_EXPR
)
9611 max
= TYPE_MAX_VALUE (TREE_TYPE (op0
));
9614 if (cond_code
== GT_EXPR
)
9616 tree one
= build_int_cst (TREE_TYPE (op0
), 1);
9617 min
= fold_build2 (PLUS_EXPR
, TREE_TYPE (op0
), min
, one
);
9618 /* Signal to compare_values_warnv this expr doesn't overflow. */
9620 TREE_NO_WARNING (min
) = 1;
9624 /* Now refine the minimum and maximum values using any
9625 value range information we have for op0. */
9628 if (compare_values (vr
->min
, min
) == 1)
9630 if (compare_values (vr
->max
, max
) == -1)
9633 /* If the new min/max values have converged to a single value,
9634 then there is only one value which can satisfy the condition,
9635 return that value. */
9636 if (operand_equal_p (min
, max
, 0) && is_gimple_min_invariant (min
))
9642 /* Return whether the value range *VR fits in an integer type specified
9643 by PRECISION and UNSIGNED_P. */
9646 range_fits_type_p (value_range
*vr
, unsigned dest_precision
, signop dest_sgn
)
9649 unsigned src_precision
;
9653 /* We can only handle integral and pointer types. */
9654 src_type
= TREE_TYPE (vr
->min
);
9655 if (!INTEGRAL_TYPE_P (src_type
)
9656 && !POINTER_TYPE_P (src_type
))
9659 /* An extension is fine unless VR is SIGNED and dest_sgn is UNSIGNED,
9660 and so is an identity transform. */
9661 src_precision
= TYPE_PRECISION (TREE_TYPE (vr
->min
));
9662 src_sgn
= TYPE_SIGN (src_type
);
9663 if ((src_precision
< dest_precision
9664 && !(dest_sgn
== UNSIGNED
&& src_sgn
== SIGNED
))
9665 || (src_precision
== dest_precision
&& src_sgn
== dest_sgn
))
9668 /* Now we can only handle ranges with constant bounds. */
9669 if (vr
->type
!= VR_RANGE
9670 || TREE_CODE (vr
->min
) != INTEGER_CST
9671 || TREE_CODE (vr
->max
) != INTEGER_CST
)
9674 /* For sign changes, the MSB of the wide_int has to be clear.
9675 An unsigned value with its MSB set cannot be represented by
9676 a signed wide_int, while a negative value cannot be represented
9677 by an unsigned wide_int. */
9678 if (src_sgn
!= dest_sgn
9679 && (wi::lts_p (wi::to_wide (vr
->min
), 0)
9680 || wi::lts_p (wi::to_wide (vr
->max
), 0)))
9683 /* Then we can perform the conversion on both ends and compare
9684 the result for equality. */
9685 tem
= wi::ext (wi::to_widest (vr
->min
), dest_precision
, dest_sgn
);
9686 if (tem
!= wi::to_widest (vr
->min
))
9688 tem
= wi::ext (wi::to_widest (vr
->max
), dest_precision
, dest_sgn
);
9689 if (tem
!= wi::to_widest (vr
->max
))
9695 /* Simplify a conditional using a relational operator to an equality
9696 test if the range information indicates only one value can satisfy
9697 the original conditional. */
9700 vr_values::simplify_cond_using_ranges_1 (gcond
*stmt
)
9702 tree op0
= gimple_cond_lhs (stmt
);
9703 tree op1
= gimple_cond_rhs (stmt
);
9704 enum tree_code cond_code
= gimple_cond_code (stmt
);
9706 if (cond_code
!= NE_EXPR
9707 && cond_code
!= EQ_EXPR
9708 && TREE_CODE (op0
) == SSA_NAME
9709 && INTEGRAL_TYPE_P (TREE_TYPE (op0
))
9710 && is_gimple_min_invariant (op1
))
9712 value_range
*vr
= get_value_range (op0
);
9714 /* If we have range information for OP0, then we might be
9715 able to simplify this conditional. */
9716 if (vr
->type
== VR_RANGE
)
9718 tree new_tree
= test_for_singularity (cond_code
, op0
, op1
, vr
);
9723 fprintf (dump_file
, "Simplified relational ");
9724 print_gimple_stmt (dump_file
, stmt
, 0);
9725 fprintf (dump_file
, " into ");
9728 gimple_cond_set_code (stmt
, EQ_EXPR
);
9729 gimple_cond_set_lhs (stmt
, op0
);
9730 gimple_cond_set_rhs (stmt
, new_tree
);
9736 print_gimple_stmt (dump_file
, stmt
, 0);
9737 fprintf (dump_file
, "\n");
9743 /* Try again after inverting the condition. We only deal
9744 with integral types here, so no need to worry about
9745 issues with inverting FP comparisons. */
9746 new_tree
= test_for_singularity
9747 (invert_tree_comparison (cond_code
, false),
9753 fprintf (dump_file
, "Simplified relational ");
9754 print_gimple_stmt (dump_file
, stmt
, 0);
9755 fprintf (dump_file
, " into ");
9758 gimple_cond_set_code (stmt
, NE_EXPR
);
9759 gimple_cond_set_lhs (stmt
, op0
);
9760 gimple_cond_set_rhs (stmt
, new_tree
);
9766 print_gimple_stmt (dump_file
, stmt
, 0);
9767 fprintf (dump_file
, "\n");
9777 /* STMT is a conditional at the end of a basic block.
9779 If the conditional is of the form SSA_NAME op constant and the SSA_NAME
9780 was set via a type conversion, try to replace the SSA_NAME with the RHS
9781 of the type conversion. Doing so makes the conversion dead which helps
9782 subsequent passes. */
9785 vr_values::simplify_cond_using_ranges_2 (gcond
*stmt
)
9787 tree op0
= gimple_cond_lhs (stmt
);
9788 tree op1
= gimple_cond_rhs (stmt
);
9790 /* If we have a comparison of an SSA_NAME (OP0) against a constant,
9791 see if OP0 was set by a type conversion where the source of
9792 the conversion is another SSA_NAME with a range that fits
9793 into the range of OP0's type.
9795 If so, the conversion is redundant as the earlier SSA_NAME can be
9796 used for the comparison directly if we just massage the constant in the
9798 if (TREE_CODE (op0
) == SSA_NAME
9799 && TREE_CODE (op1
) == INTEGER_CST
)
9801 gimple
*def_stmt
= SSA_NAME_DEF_STMT (op0
);
9804 if (!is_gimple_assign (def_stmt
)
9805 || !CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt
)))
9808 innerop
= gimple_assign_rhs1 (def_stmt
);
9810 if (TREE_CODE (innerop
) == SSA_NAME
9811 && !POINTER_TYPE_P (TREE_TYPE (innerop
))
9812 && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (innerop
)
9813 && desired_pro_or_demotion_p (TREE_TYPE (innerop
), TREE_TYPE (op0
)))
9815 value_range
*vr
= get_value_range (innerop
);
9817 if (range_int_cst_p (vr
)
9818 && range_fits_type_p (vr
,
9819 TYPE_PRECISION (TREE_TYPE (op0
)),
9820 TYPE_SIGN (TREE_TYPE (op0
)))
9821 && int_fits_type_p (op1
, TREE_TYPE (innerop
)))
9823 tree newconst
= fold_convert (TREE_TYPE (innerop
), op1
);
9824 gimple_cond_set_lhs (stmt
, innerop
);
9825 gimple_cond_set_rhs (stmt
, newconst
);
9827 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
9829 fprintf (dump_file
, "Folded into: ");
9830 print_gimple_stmt (dump_file
, stmt
, 0, TDF_SLIM
);
9831 fprintf (dump_file
, "\n");
9838 /* Simplify a switch statement using the value range of the switch
9842 vr_values::simplify_switch_using_ranges (gswitch
*stmt
)
9844 tree op
= gimple_switch_index (stmt
);
9845 value_range
*vr
= NULL
;
9849 size_t i
= 0, j
= 0, n
, n2
;
9852 size_t k
= 1, l
= 0;
9854 if (TREE_CODE (op
) == SSA_NAME
)
9856 vr
= get_value_range (op
);
9858 /* We can only handle integer ranges. */
9859 if ((vr
->type
!= VR_RANGE
9860 && vr
->type
!= VR_ANTI_RANGE
)
9861 || symbolic_range_p (vr
))
9864 /* Find case label for min/max of the value range. */
9865 take_default
= !find_case_label_ranges (stmt
, vr
, &i
, &j
, &k
, &l
);
9867 else if (TREE_CODE (op
) == INTEGER_CST
)
9869 take_default
= !find_case_label_index (stmt
, 1, op
, &i
);
9883 n
= gimple_switch_num_labels (stmt
);
9885 /* We can truncate the case label ranges that partially overlap with OP's
9887 size_t min_idx
= 1, max_idx
= 0;
9889 find_case_label_range (stmt
, vr
->min
, vr
->max
, &min_idx
, &max_idx
);
9890 if (min_idx
<= max_idx
)
9892 tree min_label
= gimple_switch_label (stmt
, min_idx
);
9893 tree max_label
= gimple_switch_label (stmt
, max_idx
);
9895 /* Avoid changing the type of the case labels when truncating. */
9896 tree case_label_type
= TREE_TYPE (CASE_LOW (min_label
));
9897 tree vr_min
= fold_convert (case_label_type
, vr
->min
);
9898 tree vr_max
= fold_convert (case_label_type
, vr
->max
);
9900 if (vr
->type
== VR_RANGE
)
9902 /* If OP's value range is [2,8] and the low label range is
9903 0 ... 3, truncate the label's range to 2 .. 3. */
9904 if (tree_int_cst_compare (CASE_LOW (min_label
), vr_min
) < 0
9905 && CASE_HIGH (min_label
) != NULL_TREE
9906 && tree_int_cst_compare (CASE_HIGH (min_label
), vr_min
) >= 0)
9907 CASE_LOW (min_label
) = vr_min
;
9909 /* If OP's value range is [2,8] and the high label range is
9910 7 ... 10, truncate the label's range to 7 .. 8. */
9911 if (tree_int_cst_compare (CASE_LOW (max_label
), vr_max
) <= 0
9912 && CASE_HIGH (max_label
) != NULL_TREE
9913 && tree_int_cst_compare (CASE_HIGH (max_label
), vr_max
) > 0)
9914 CASE_HIGH (max_label
) = vr_max
;
9916 else if (vr
->type
== VR_ANTI_RANGE
)
9918 tree one_cst
= build_one_cst (case_label_type
);
9920 if (min_label
== max_label
)
9922 /* If OP's value range is ~[7,8] and the label's range is
9923 7 ... 10, truncate the label's range to 9 ... 10. */
9924 if (tree_int_cst_compare (CASE_LOW (min_label
), vr_min
) == 0
9925 && CASE_HIGH (min_label
) != NULL_TREE
9926 && tree_int_cst_compare (CASE_HIGH (min_label
), vr_max
) > 0)
9927 CASE_LOW (min_label
)
9928 = int_const_binop (PLUS_EXPR
, vr_max
, one_cst
);
9930 /* If OP's value range is ~[7,8] and the label's range is
9931 5 ... 8, truncate the label's range to 5 ... 6. */
9932 if (tree_int_cst_compare (CASE_LOW (min_label
), vr_min
) < 0
9933 && CASE_HIGH (min_label
) != NULL_TREE
9934 && tree_int_cst_compare (CASE_HIGH (min_label
), vr_max
) == 0)
9935 CASE_HIGH (min_label
)
9936 = int_const_binop (MINUS_EXPR
, vr_min
, one_cst
);
9940 /* If OP's value range is ~[2,8] and the low label range is
9941 0 ... 3, truncate the label's range to 0 ... 1. */
9942 if (tree_int_cst_compare (CASE_LOW (min_label
), vr_min
) < 0
9943 && CASE_HIGH (min_label
) != NULL_TREE
9944 && tree_int_cst_compare (CASE_HIGH (min_label
), vr_min
) >= 0)
9945 CASE_HIGH (min_label
)
9946 = int_const_binop (MINUS_EXPR
, vr_min
, one_cst
);
9948 /* If OP's value range is ~[2,8] and the high label range is
9949 7 ... 10, truncate the label's range to 9 ... 10. */
9950 if (tree_int_cst_compare (CASE_LOW (max_label
), vr_max
) <= 0
9951 && CASE_HIGH (max_label
) != NULL_TREE
9952 && tree_int_cst_compare (CASE_HIGH (max_label
), vr_max
) > 0)
9953 CASE_LOW (max_label
)
9954 = int_const_binop (PLUS_EXPR
, vr_max
, one_cst
);
9958 /* Canonicalize singleton case ranges. */
9959 if (tree_int_cst_equal (CASE_LOW (min_label
), CASE_HIGH (min_label
)))
9960 CASE_HIGH (min_label
) = NULL_TREE
;
9961 if (tree_int_cst_equal (CASE_LOW (max_label
), CASE_HIGH (max_label
)))
9962 CASE_HIGH (max_label
) = NULL_TREE
;
9965 /* We can also eliminate case labels that lie completely outside OP's value
9968 /* Bail out if this is just all edges taken. */
9974 /* Build a new vector of taken case labels. */
9975 vec2
= make_tree_vec (j
- i
+ 1 + l
- k
+ 1 + (int)take_default
);
9978 /* Add the default edge, if necessary. */
9980 TREE_VEC_ELT (vec2
, n2
++) = gimple_switch_default_label (stmt
);
9982 for (; i
<= j
; ++i
, ++n2
)
9983 TREE_VEC_ELT (vec2
, n2
) = gimple_switch_label (stmt
, i
);
9985 for (; k
<= l
; ++k
, ++n2
)
9986 TREE_VEC_ELT (vec2
, n2
) = gimple_switch_label (stmt
, k
);
9988 /* Mark needed edges. */
9989 for (i
= 0; i
< n2
; ++i
)
9991 e
= find_edge (gimple_bb (stmt
),
9992 label_to_block (CASE_LABEL (TREE_VEC_ELT (vec2
, i
))));
9993 e
->aux
= (void *)-1;
9996 /* Queue not needed edges for later removal. */
9997 FOR_EACH_EDGE (e
, ei
, gimple_bb (stmt
)->succs
)
9999 if (e
->aux
== (void *)-1)
10005 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
10007 fprintf (dump_file
, "removing unreachable case label\n");
10009 to_remove_edges
.safe_push (e
);
10010 e
->flags
&= ~EDGE_EXECUTABLE
;
10013 /* And queue an update for the stmt. */
10016 to_update_switch_stmts
.safe_push (su
);
10020 /* Simplify an integral conversion from an SSA name in STMT. */
10023 simplify_conversion_using_ranges (gimple_stmt_iterator
*gsi
, gimple
*stmt
)
10025 tree innerop
, middleop
, finaltype
;
10027 signop inner_sgn
, middle_sgn
, final_sgn
;
10028 unsigned inner_prec
, middle_prec
, final_prec
;
10029 widest_int innermin
, innermed
, innermax
, middlemin
, middlemed
, middlemax
;
10031 finaltype
= TREE_TYPE (gimple_assign_lhs (stmt
));
10032 if (!INTEGRAL_TYPE_P (finaltype
))
10034 middleop
= gimple_assign_rhs1 (stmt
);
10035 def_stmt
= SSA_NAME_DEF_STMT (middleop
);
10036 if (!is_gimple_assign (def_stmt
)
10037 || !CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt
)))
10039 innerop
= gimple_assign_rhs1 (def_stmt
);
10040 if (TREE_CODE (innerop
) != SSA_NAME
10041 || SSA_NAME_OCCURS_IN_ABNORMAL_PHI (innerop
))
10044 /* Get the value-range of the inner operand. Use get_range_info in
10045 case innerop was created during substitute-and-fold. */
10046 wide_int imin
, imax
;
10047 if (!INTEGRAL_TYPE_P (TREE_TYPE (innerop
))
10048 || get_range_info (innerop
, &imin
, &imax
) != VR_RANGE
)
10050 innermin
= widest_int::from (imin
, TYPE_SIGN (TREE_TYPE (innerop
)));
10051 innermax
= widest_int::from (imax
, TYPE_SIGN (TREE_TYPE (innerop
)));
10053 /* Simulate the conversion chain to check if the result is equal if
10054 the middle conversion is removed. */
10055 inner_prec
= TYPE_PRECISION (TREE_TYPE (innerop
));
10056 middle_prec
= TYPE_PRECISION (TREE_TYPE (middleop
));
10057 final_prec
= TYPE_PRECISION (finaltype
);
10059 /* If the first conversion is not injective, the second must not
10061 if (wi::gtu_p (innermax
- innermin
,
10062 wi::mask
<widest_int
> (middle_prec
, false))
10063 && middle_prec
< final_prec
)
10065 /* We also want a medium value so that we can track the effect that
10066 narrowing conversions with sign change have. */
10067 inner_sgn
= TYPE_SIGN (TREE_TYPE (innerop
));
10068 if (inner_sgn
== UNSIGNED
)
10069 innermed
= wi::shifted_mask
<widest_int
> (1, inner_prec
- 1, false);
10072 if (wi::cmp (innermin
, innermed
, inner_sgn
) >= 0
10073 || wi::cmp (innermed
, innermax
, inner_sgn
) >= 0)
10074 innermed
= innermin
;
10076 middle_sgn
= TYPE_SIGN (TREE_TYPE (middleop
));
10077 middlemin
= wi::ext (innermin
, middle_prec
, middle_sgn
);
10078 middlemed
= wi::ext (innermed
, middle_prec
, middle_sgn
);
10079 middlemax
= wi::ext (innermax
, middle_prec
, middle_sgn
);
10081 /* Require that the final conversion applied to both the original
10082 and the intermediate range produces the same result. */
10083 final_sgn
= TYPE_SIGN (finaltype
);
10084 if (wi::ext (middlemin
, final_prec
, final_sgn
)
10085 != wi::ext (innermin
, final_prec
, final_sgn
)
10086 || wi::ext (middlemed
, final_prec
, final_sgn
)
10087 != wi::ext (innermed
, final_prec
, final_sgn
)
10088 || wi::ext (middlemax
, final_prec
, final_sgn
)
10089 != wi::ext (innermax
, final_prec
, final_sgn
))
10092 gimple_assign_set_rhs1 (stmt
, innerop
);
10093 fold_stmt (gsi
, follow_single_use_edges
);
10097 /* Simplify a conversion from integral SSA name to float in STMT. */
10100 vr_values::simplify_float_conversion_using_ranges (gimple_stmt_iterator
*gsi
,
10103 tree rhs1
= gimple_assign_rhs1 (stmt
);
10104 value_range
*vr
= get_value_range (rhs1
);
10105 scalar_float_mode fltmode
10106 = SCALAR_FLOAT_TYPE_MODE (TREE_TYPE (gimple_assign_lhs (stmt
)));
10107 scalar_int_mode mode
;
10111 /* We can only handle constant ranges. */
10112 if (vr
->type
!= VR_RANGE
10113 || TREE_CODE (vr
->min
) != INTEGER_CST
10114 || TREE_CODE (vr
->max
) != INTEGER_CST
)
10117 /* First check if we can use a signed type in place of an unsigned. */
10118 scalar_int_mode rhs_mode
= SCALAR_INT_TYPE_MODE (TREE_TYPE (rhs1
));
10119 if (TYPE_UNSIGNED (TREE_TYPE (rhs1
))
10120 && can_float_p (fltmode
, rhs_mode
, 0) != CODE_FOR_nothing
10121 && range_fits_type_p (vr
, TYPE_PRECISION (TREE_TYPE (rhs1
)), SIGNED
))
10123 /* If we can do the conversion in the current input mode do nothing. */
10124 else if (can_float_p (fltmode
, rhs_mode
,
10125 TYPE_UNSIGNED (TREE_TYPE (rhs1
))) != CODE_FOR_nothing
)
10127 /* Otherwise search for a mode we can use, starting from the narrowest
10128 integer mode available. */
10131 mode
= NARROWEST_INT_MODE
;
10134 /* If we cannot do a signed conversion to float from mode
10135 or if the value-range does not fit in the signed type
10136 try with a wider mode. */
10137 if (can_float_p (fltmode
, mode
, 0) != CODE_FOR_nothing
10138 && range_fits_type_p (vr
, GET_MODE_PRECISION (mode
), SIGNED
))
10141 /* But do not widen the input. Instead leave that to the
10142 optabs expansion code. */
10143 if (!GET_MODE_WIDER_MODE (mode
).exists (&mode
)
10144 || GET_MODE_PRECISION (mode
) > TYPE_PRECISION (TREE_TYPE (rhs1
)))
10149 /* It works, insert a truncation or sign-change before the
10150 float conversion. */
10151 tem
= make_ssa_name (build_nonstandard_integer_type
10152 (GET_MODE_PRECISION (mode
), 0));
10153 conv
= gimple_build_assign (tem
, NOP_EXPR
, rhs1
);
10154 gsi_insert_before (gsi
, conv
, GSI_SAME_STMT
);
10155 gimple_assign_set_rhs1 (stmt
, tem
);
10156 fold_stmt (gsi
, follow_single_use_edges
);
10161 /* Simplify an internal fn call using ranges if possible. */
10164 vr_values::simplify_internal_call_using_ranges (gimple_stmt_iterator
*gsi
,
10167 enum tree_code subcode
;
10168 bool is_ubsan
= false;
10170 switch (gimple_call_internal_fn (stmt
))
10172 case IFN_UBSAN_CHECK_ADD
:
10173 subcode
= PLUS_EXPR
;
10176 case IFN_UBSAN_CHECK_SUB
:
10177 subcode
= MINUS_EXPR
;
10180 case IFN_UBSAN_CHECK_MUL
:
10181 subcode
= MULT_EXPR
;
10184 case IFN_ADD_OVERFLOW
:
10185 subcode
= PLUS_EXPR
;
10187 case IFN_SUB_OVERFLOW
:
10188 subcode
= MINUS_EXPR
;
10190 case IFN_MUL_OVERFLOW
:
10191 subcode
= MULT_EXPR
;
10197 tree op0
= gimple_call_arg (stmt
, 0);
10198 tree op1
= gimple_call_arg (stmt
, 1);
10202 type
= TREE_TYPE (op0
);
10203 if (VECTOR_TYPE_P (type
))
10206 else if (gimple_call_lhs (stmt
) == NULL_TREE
)
10209 type
= TREE_TYPE (TREE_TYPE (gimple_call_lhs (stmt
)));
10210 if (!check_for_binary_op_overflow (subcode
, type
, op0
, op1
, &ovf
)
10211 || (is_ubsan
&& ovf
))
10215 location_t loc
= gimple_location (stmt
);
10217 g
= gimple_build_assign (gimple_call_lhs (stmt
), subcode
, op0
, op1
);
10220 int prec
= TYPE_PRECISION (type
);
10223 || !useless_type_conversion_p (type
, TREE_TYPE (op0
))
10224 || !useless_type_conversion_p (type
, TREE_TYPE (op1
)))
10225 utype
= build_nonstandard_integer_type (prec
, 1);
10226 if (TREE_CODE (op0
) == INTEGER_CST
)
10227 op0
= fold_convert (utype
, op0
);
10228 else if (!useless_type_conversion_p (utype
, TREE_TYPE (op0
)))
10230 g
= gimple_build_assign (make_ssa_name (utype
), NOP_EXPR
, op0
);
10231 gimple_set_location (g
, loc
);
10232 gsi_insert_before (gsi
, g
, GSI_SAME_STMT
);
10233 op0
= gimple_assign_lhs (g
);
10235 if (TREE_CODE (op1
) == INTEGER_CST
)
10236 op1
= fold_convert (utype
, op1
);
10237 else if (!useless_type_conversion_p (utype
, TREE_TYPE (op1
)))
10239 g
= gimple_build_assign (make_ssa_name (utype
), NOP_EXPR
, op1
);
10240 gimple_set_location (g
, loc
);
10241 gsi_insert_before (gsi
, g
, GSI_SAME_STMT
);
10242 op1
= gimple_assign_lhs (g
);
10244 g
= gimple_build_assign (make_ssa_name (utype
), subcode
, op0
, op1
);
10245 gimple_set_location (g
, loc
);
10246 gsi_insert_before (gsi
, g
, GSI_SAME_STMT
);
10249 g
= gimple_build_assign (make_ssa_name (type
), NOP_EXPR
,
10250 gimple_assign_lhs (g
));
10251 gimple_set_location (g
, loc
);
10252 gsi_insert_before (gsi
, g
, GSI_SAME_STMT
);
10254 g
= gimple_build_assign (gimple_call_lhs (stmt
), COMPLEX_EXPR
,
10255 gimple_assign_lhs (g
),
10256 build_int_cst (type
, ovf
));
10258 gimple_set_location (g
, loc
);
10259 gsi_replace (gsi
, g
, false);
10263 /* Return true if VAR is a two-valued variable. Set a and b with the
10264 two-values when it is true. Return false otherwise. */
10267 vr_values::two_valued_val_range_p (tree var
, tree
*a
, tree
*b
)
10269 value_range
*vr
= get_value_range (var
);
10270 if ((vr
->type
!= VR_RANGE
10271 && vr
->type
!= VR_ANTI_RANGE
)
10272 || TREE_CODE (vr
->min
) != INTEGER_CST
10273 || TREE_CODE (vr
->max
) != INTEGER_CST
)
10276 if (vr
->type
== VR_RANGE
10277 && wi::to_wide (vr
->max
) - wi::to_wide (vr
->min
) == 1)
10284 /* ~[TYPE_MIN + 1, TYPE_MAX - 1] */
10285 if (vr
->type
== VR_ANTI_RANGE
10286 && (wi::to_wide (vr
->min
)
10287 - wi::to_wide (vrp_val_min (TREE_TYPE (var
)))) == 1
10288 && (wi::to_wide (vrp_val_max (TREE_TYPE (var
)))
10289 - wi::to_wide (vr
->max
)) == 1)
10291 *a
= vrp_val_min (TREE_TYPE (var
));
10292 *b
= vrp_val_max (TREE_TYPE (var
));
10299 /* Simplify STMT using ranges if possible. */
10302 vr_values::simplify_stmt_using_ranges (gimple_stmt_iterator
*gsi
)
10304 gimple
*stmt
= gsi_stmt (*gsi
);
10305 if (is_gimple_assign (stmt
))
10307 enum tree_code rhs_code
= gimple_assign_rhs_code (stmt
);
10308 tree rhs1
= gimple_assign_rhs1 (stmt
);
10309 tree rhs2
= gimple_assign_rhs2 (stmt
);
10310 tree lhs
= gimple_assign_lhs (stmt
);
10311 tree val1
= NULL_TREE
, val2
= NULL_TREE
;
10312 use_operand_p use_p
;
10316 LHS = CST BINOP VAR
10317 Where VAR is two-valued and LHS is used in GIMPLE_COND only
10319 LHS = VAR == VAL1 ? (CST BINOP VAL1) : (CST BINOP VAL2)
10322 LHS = VAR BINOP CST
10323 Where VAR is two-valued and LHS is used in GIMPLE_COND only
10325 LHS = VAR == VAL1 ? (VAL1 BINOP CST) : (VAL2 BINOP CST) */
10327 if (TREE_CODE_CLASS (rhs_code
) == tcc_binary
10328 && INTEGRAL_TYPE_P (TREE_TYPE (lhs
))
10329 && ((TREE_CODE (rhs1
) == INTEGER_CST
10330 && TREE_CODE (rhs2
) == SSA_NAME
)
10331 || (TREE_CODE (rhs2
) == INTEGER_CST
10332 && TREE_CODE (rhs1
) == SSA_NAME
))
10333 && single_imm_use (lhs
, &use_p
, &use_stmt
)
10334 && gimple_code (use_stmt
) == GIMPLE_COND
)
10337 tree new_rhs1
= NULL_TREE
;
10338 tree new_rhs2
= NULL_TREE
;
10339 tree cmp_var
= NULL_TREE
;
10341 if (TREE_CODE (rhs2
) == SSA_NAME
10342 && two_valued_val_range_p (rhs2
, &val1
, &val2
))
10344 /* Optimize RHS1 OP [VAL1, VAL2]. */
10345 new_rhs1
= int_const_binop (rhs_code
, rhs1
, val1
);
10346 new_rhs2
= int_const_binop (rhs_code
, rhs1
, val2
);
10349 else if (TREE_CODE (rhs1
) == SSA_NAME
10350 && two_valued_val_range_p (rhs1
, &val1
, &val2
))
10352 /* Optimize [VAL1, VAL2] OP RHS2. */
10353 new_rhs1
= int_const_binop (rhs_code
, val1
, rhs2
);
10354 new_rhs2
= int_const_binop (rhs_code
, val2
, rhs2
);
10358 /* If we could not find two-vals or the optimzation is invalid as
10359 in divide by zero, new_rhs1 / new_rhs will be NULL_TREE. */
10360 if (new_rhs1
&& new_rhs2
)
10362 tree cond
= build2 (EQ_EXPR
, boolean_type_node
, cmp_var
, val1
);
10363 gimple_assign_set_rhs_with_ops (gsi
,
10367 update_stmt (gsi_stmt (*gsi
));
10368 fold_stmt (gsi
, follow_single_use_edges
);
10377 /* Transform EQ_EXPR, NE_EXPR into BIT_XOR_EXPR or identity
10378 if the RHS is zero or one, and the LHS are known to be boolean
10380 if (INTEGRAL_TYPE_P (TREE_TYPE (rhs1
)))
10381 return simplify_truth_ops_using_ranges (gsi
, stmt
);
10384 /* Transform TRUNC_DIV_EXPR and TRUNC_MOD_EXPR into RSHIFT_EXPR
10385 and BIT_AND_EXPR respectively if the first operand is greater
10386 than zero and the second operand is an exact power of two.
10387 Also optimize TRUNC_MOD_EXPR away if the second operand is
10388 constant and the first operand already has the right value
10390 case TRUNC_DIV_EXPR
:
10391 case TRUNC_MOD_EXPR
:
10392 if ((TREE_CODE (rhs1
) == SSA_NAME
10393 || TREE_CODE (rhs1
) == INTEGER_CST
)
10394 && INTEGRAL_TYPE_P (TREE_TYPE (rhs1
)))
10395 return simplify_div_or_mod_using_ranges (gsi
, stmt
);
10398 /* Transform ABS (X) into X or -X as appropriate. */
10400 if (TREE_CODE (rhs1
) == SSA_NAME
10401 && INTEGRAL_TYPE_P (TREE_TYPE (rhs1
)))
10402 return simplify_abs_using_ranges (gsi
, stmt
);
10407 /* Optimize away BIT_AND_EXPR and BIT_IOR_EXPR
10408 if all the bits being cleared are already cleared or
10409 all the bits being set are already set. */
10410 if (INTEGRAL_TYPE_P (TREE_TYPE (rhs1
)))
10411 return simplify_bit_ops_using_ranges (gsi
, stmt
);
10415 if (TREE_CODE (rhs1
) == SSA_NAME
10416 && INTEGRAL_TYPE_P (TREE_TYPE (rhs1
)))
10417 return simplify_conversion_using_ranges (gsi
, stmt
);
10421 if (TREE_CODE (rhs1
) == SSA_NAME
10422 && INTEGRAL_TYPE_P (TREE_TYPE (rhs1
)))
10423 return simplify_float_conversion_using_ranges (gsi
, stmt
);
10428 return simplify_min_or_max_using_ranges (gsi
, stmt
);
10434 else if (gimple_code (stmt
) == GIMPLE_COND
)
10435 return simplify_cond_using_ranges_1 (as_a
<gcond
*> (stmt
));
10436 else if (gimple_code (stmt
) == GIMPLE_SWITCH
)
10437 return simplify_switch_using_ranges (as_a
<gswitch
*> (stmt
));
10438 else if (is_gimple_call (stmt
)
10439 && gimple_call_internal_p (stmt
))
10440 return simplify_internal_call_using_ranges (gsi
, stmt
);
10445 class vrp_folder
: public substitute_and_fold_engine
10448 tree
get_value (tree
) FINAL OVERRIDE
;
10449 bool fold_stmt (gimple_stmt_iterator
*) FINAL OVERRIDE
;
10450 bool fold_predicate_in (gimple_stmt_iterator
*);
10452 class vr_values
*vr_values
;
10455 tree
vrp_evaluate_conditional (tree_code code
, tree op0
,
10456 tree op1
, gimple
*stmt
)
10457 { return vr_values
->vrp_evaluate_conditional (code
, op0
, op1
, stmt
); }
10458 bool simplify_stmt_using_ranges (gimple_stmt_iterator
*gsi
)
10459 { return vr_values
->simplify_stmt_using_ranges (gsi
); }
10460 tree
op_with_constant_singleton_value_range (tree op
)
10461 { return vr_values
->op_with_constant_singleton_value_range (op
); }
10464 /* If the statement pointed by SI has a predicate whose value can be
10465 computed using the value range information computed by VRP, compute
10466 its value and return true. Otherwise, return false. */
10469 vrp_folder::fold_predicate_in (gimple_stmt_iterator
*si
)
10471 bool assignment_p
= false;
10473 gimple
*stmt
= gsi_stmt (*si
);
10475 if (is_gimple_assign (stmt
)
10476 && TREE_CODE_CLASS (gimple_assign_rhs_code (stmt
)) == tcc_comparison
)
10478 assignment_p
= true;
10479 val
= vrp_evaluate_conditional (gimple_assign_rhs_code (stmt
),
10480 gimple_assign_rhs1 (stmt
),
10481 gimple_assign_rhs2 (stmt
),
10484 else if (gcond
*cond_stmt
= dyn_cast
<gcond
*> (stmt
))
10485 val
= vrp_evaluate_conditional (gimple_cond_code (cond_stmt
),
10486 gimple_cond_lhs (cond_stmt
),
10487 gimple_cond_rhs (cond_stmt
),
10495 val
= fold_convert (gimple_expr_type (stmt
), val
);
10499 fprintf (dump_file
, "Folding predicate ");
10500 print_gimple_expr (dump_file
, stmt
, 0);
10501 fprintf (dump_file
, " to ");
10502 print_generic_expr (dump_file
, val
);
10503 fprintf (dump_file
, "\n");
10506 if (is_gimple_assign (stmt
))
10507 gimple_assign_set_rhs_from_tree (si
, val
);
10510 gcc_assert (gimple_code (stmt
) == GIMPLE_COND
);
10511 gcond
*cond_stmt
= as_a
<gcond
*> (stmt
);
10512 if (integer_zerop (val
))
10513 gimple_cond_make_false (cond_stmt
);
10514 else if (integer_onep (val
))
10515 gimple_cond_make_true (cond_stmt
);
10517 gcc_unreachable ();
10526 /* Callback for substitute_and_fold folding the stmt at *SI. */
10529 vrp_folder::fold_stmt (gimple_stmt_iterator
*si
)
10531 if (fold_predicate_in (si
))
10534 return simplify_stmt_using_ranges (si
);
10537 /* If OP has a value range with a single constant value return that,
10538 otherwise return NULL_TREE. This returns OP itself if OP is a
10541 Implemented as a pure wrapper right now, but this will change. */
10544 vrp_folder::get_value (tree op
)
10546 return op_with_constant_singleton_value_range (op
);
10549 /* Return the LHS of any ASSERT_EXPR where OP appears as the first
10550 argument to the ASSERT_EXPR and in which the ASSERT_EXPR dominates
10551 BB. If no such ASSERT_EXPR is found, return OP. */
10554 lhs_of_dominating_assert (tree op
, basic_block bb
, gimple
*stmt
)
10556 imm_use_iterator imm_iter
;
10558 use_operand_p use_p
;
10560 if (TREE_CODE (op
) == SSA_NAME
)
10562 FOR_EACH_IMM_USE_FAST (use_p
, imm_iter
, op
)
10564 use_stmt
= USE_STMT (use_p
);
10565 if (use_stmt
!= stmt
10566 && gimple_assign_single_p (use_stmt
)
10567 && TREE_CODE (gimple_assign_rhs1 (use_stmt
)) == ASSERT_EXPR
10568 && TREE_OPERAND (gimple_assign_rhs1 (use_stmt
), 0) == op
10569 && dominated_by_p (CDI_DOMINATORS
, bb
, gimple_bb (use_stmt
)))
10570 return gimple_assign_lhs (use_stmt
);
10576 /* A trivial wrapper so that we can present the generic jump threading
10577 code with a simple API for simplifying statements. STMT is the
10578 statement we want to simplify, WITHIN_STMT provides the location
10579 for any overflow warnings. */
10582 simplify_stmt_for_jump_threading (gimple
*stmt
, gimple
*within_stmt
,
10583 class avail_exprs_stack
*avail_exprs_stack ATTRIBUTE_UNUSED
,
10586 /* First see if the conditional is in the hash table. */
10587 tree cached_lhs
= avail_exprs_stack
->lookup_avail_expr (stmt
, false, true);
10588 if (cached_lhs
&& is_gimple_min_invariant (cached_lhs
))
10591 vr_values
*vr_values
= x_vr_values
;
10592 if (gcond
*cond_stmt
= dyn_cast
<gcond
*> (stmt
))
10594 tree op0
= gimple_cond_lhs (cond_stmt
);
10595 op0
= lhs_of_dominating_assert (op0
, bb
, stmt
);
10597 tree op1
= gimple_cond_rhs (cond_stmt
);
10598 op1
= lhs_of_dominating_assert (op1
, bb
, stmt
);
10600 return vr_values
->vrp_evaluate_conditional (gimple_cond_code (cond_stmt
),
10601 op0
, op1
, within_stmt
);
10604 /* We simplify a switch statement by trying to determine which case label
10605 will be taken. If we are successful then we return the corresponding
10606 CASE_LABEL_EXPR. */
10607 if (gswitch
*switch_stmt
= dyn_cast
<gswitch
*> (stmt
))
10609 tree op
= gimple_switch_index (switch_stmt
);
10610 if (TREE_CODE (op
) != SSA_NAME
)
10613 op
= lhs_of_dominating_assert (op
, bb
, stmt
);
10615 value_range
*vr
= vr_values
->get_value_range (op
);
10616 if ((vr
->type
!= VR_RANGE
&& vr
->type
!= VR_ANTI_RANGE
)
10617 || symbolic_range_p (vr
))
10620 if (vr
->type
== VR_RANGE
)
10623 /* Get the range of labels that contain a part of the operand's
10625 find_case_label_range (switch_stmt
, vr
->min
, vr
->max
, &i
, &j
);
10627 /* Is there only one such label? */
10630 tree label
= gimple_switch_label (switch_stmt
, i
);
10632 /* The i'th label will be taken only if the value range of the
10633 operand is entirely within the bounds of this label. */
10634 if (CASE_HIGH (label
) != NULL_TREE
10635 ? (tree_int_cst_compare (CASE_LOW (label
), vr
->min
) <= 0
10636 && tree_int_cst_compare (CASE_HIGH (label
), vr
->max
) >= 0)
10637 : (tree_int_cst_equal (CASE_LOW (label
), vr
->min
)
10638 && tree_int_cst_equal (vr
->min
, vr
->max
)))
10642 /* If there are no such labels then the default label will be
10645 return gimple_switch_label (switch_stmt
, 0);
10648 if (vr
->type
== VR_ANTI_RANGE
)
10650 unsigned n
= gimple_switch_num_labels (switch_stmt
);
10651 tree min_label
= gimple_switch_label (switch_stmt
, 1);
10652 tree max_label
= gimple_switch_label (switch_stmt
, n
- 1);
10654 /* The default label will be taken only if the anti-range of the
10655 operand is entirely outside the bounds of all the (non-default)
10657 if (tree_int_cst_compare (vr
->min
, CASE_LOW (min_label
)) <= 0
10658 && (CASE_HIGH (max_label
) != NULL_TREE
10659 ? tree_int_cst_compare (vr
->max
, CASE_HIGH (max_label
)) >= 0
10660 : tree_int_cst_compare (vr
->max
, CASE_LOW (max_label
)) >= 0))
10661 return gimple_switch_label (switch_stmt
, 0);
10667 if (gassign
*assign_stmt
= dyn_cast
<gassign
*> (stmt
))
10669 value_range new_vr
= VR_INITIALIZER
;
10670 tree lhs
= gimple_assign_lhs (assign_stmt
);
10672 if (TREE_CODE (lhs
) == SSA_NAME
10673 && (INTEGRAL_TYPE_P (TREE_TYPE (lhs
))
10674 || POINTER_TYPE_P (TREE_TYPE (lhs
))))
10676 vr_values
->extract_range_from_assignment (&new_vr
, assign_stmt
);
10677 if (range_int_cst_singleton_p (&new_vr
))
10685 class vrp_dom_walker
: public dom_walker
10688 vrp_dom_walker (cdi_direction direction
,
10689 class const_and_copies
*const_and_copies
,
10690 class avail_exprs_stack
*avail_exprs_stack
)
10691 : dom_walker (direction
, true),
10692 m_const_and_copies (const_and_copies
),
10693 m_avail_exprs_stack (avail_exprs_stack
),
10694 m_dummy_cond (NULL
) {}
10696 virtual edge
before_dom_children (basic_block
);
10697 virtual void after_dom_children (basic_block
);
10699 class vr_values
*vr_values
;
10702 class const_and_copies
*m_const_and_copies
;
10703 class avail_exprs_stack
*m_avail_exprs_stack
;
10705 gcond
*m_dummy_cond
;
10709 /* Called before processing dominator children of BB. We want to look
10710 at ASSERT_EXPRs and record information from them in the appropriate
10713 We could look at other statements here. It's not seen as likely
10714 to significantly increase the jump threads we discover. */
10717 vrp_dom_walker::before_dom_children (basic_block bb
)
10719 gimple_stmt_iterator gsi
;
10721 m_avail_exprs_stack
->push_marker ();
10722 m_const_and_copies
->push_marker ();
10723 for (gsi
= gsi_start_nondebug_bb (bb
); !gsi_end_p (gsi
); gsi_next (&gsi
))
10725 gimple
*stmt
= gsi_stmt (gsi
);
10726 if (gimple_assign_single_p (stmt
)
10727 && TREE_CODE (gimple_assign_rhs1 (stmt
)) == ASSERT_EXPR
)
10729 tree rhs1
= gimple_assign_rhs1 (stmt
);
10730 tree cond
= TREE_OPERAND (rhs1
, 1);
10731 tree inverted
= invert_truthvalue (cond
);
10732 vec
<cond_equivalence
> p
;
10734 record_conditions (&p
, cond
, inverted
);
10735 for (unsigned int i
= 0; i
< p
.length (); i
++)
10736 m_avail_exprs_stack
->record_cond (&p
[i
]);
10738 tree lhs
= gimple_assign_lhs (stmt
);
10739 m_const_and_copies
->record_const_or_copy (lhs
,
10740 TREE_OPERAND (rhs1
, 0));
10749 /* Called after processing dominator children of BB. This is where we
10750 actually call into the threader. */
10752 vrp_dom_walker::after_dom_children (basic_block bb
)
10755 m_dummy_cond
= gimple_build_cond (NE_EXPR
,
10756 integer_zero_node
, integer_zero_node
,
10759 x_vr_values
= vr_values
;
10760 thread_outgoing_edges (bb
, m_dummy_cond
, m_const_and_copies
,
10761 m_avail_exprs_stack
,
10762 simplify_stmt_for_jump_threading
);
10763 x_vr_values
= NULL
;
10765 m_avail_exprs_stack
->pop_to_marker ();
10766 m_const_and_copies
->pop_to_marker ();
10769 /* Blocks which have more than one predecessor and more than
10770 one successor present jump threading opportunities, i.e.,
10771 when the block is reached from a specific predecessor, we
10772 may be able to determine which of the outgoing edges will
10773 be traversed. When this optimization applies, we are able
10774 to avoid conditionals at runtime and we may expose secondary
10775 optimization opportunities.
10777 This routine is effectively a driver for the generic jump
10778 threading code. It basically just presents the generic code
10779 with edges that may be suitable for jump threading.
10781 Unlike DOM, we do not iterate VRP if jump threading was successful.
10782 While iterating may expose new opportunities for VRP, it is expected
10783 those opportunities would be very limited and the compile time cost
10784 to expose those opportunities would be significant.
10786 As jump threading opportunities are discovered, they are registered
10787 for later realization. */
10790 identify_jump_threads (class vr_values
*vr_values
)
10795 /* Ugh. When substituting values earlier in this pass we can
10796 wipe the dominance information. So rebuild the dominator
10797 information as we need it within the jump threading code. */
10798 calculate_dominance_info (CDI_DOMINATORS
);
10800 /* We do not allow VRP information to be used for jump threading
10801 across a back edge in the CFG. Otherwise it becomes too
10802 difficult to avoid eliminating loop exit tests. Of course
10803 EDGE_DFS_BACK is not accurate at this time so we have to
10805 mark_dfs_back_edges ();
10807 /* Do not thread across edges we are about to remove. Just marking
10808 them as EDGE_IGNORE will do. */
10809 FOR_EACH_VEC_ELT (to_remove_edges
, i
, e
)
10810 e
->flags
|= EDGE_IGNORE
;
10812 /* Allocate our unwinder stack to unwind any temporary equivalences
10813 that might be recorded. */
10814 const_and_copies
*equiv_stack
= new const_and_copies ();
10816 hash_table
<expr_elt_hasher
> *avail_exprs
10817 = new hash_table
<expr_elt_hasher
> (1024);
10818 avail_exprs_stack
*avail_exprs_stack
10819 = new class avail_exprs_stack (avail_exprs
);
10821 vrp_dom_walker
walker (CDI_DOMINATORS
, equiv_stack
, avail_exprs_stack
);
10822 walker
.vr_values
= vr_values
;
10823 walker
.walk (cfun
->cfg
->x_entry_block_ptr
);
10825 /* Clear EDGE_IGNORE. */
10826 FOR_EACH_VEC_ELT (to_remove_edges
, i
, e
)
10827 e
->flags
&= ~EDGE_IGNORE
;
10829 /* We do not actually update the CFG or SSA graphs at this point as
10830 ASSERT_EXPRs are still in the IL and cfg cleanup code does not yet
10831 handle ASSERT_EXPRs gracefully. */
10832 delete equiv_stack
;
10833 delete avail_exprs
;
10834 delete avail_exprs_stack
;
10837 /* Free VRP lattice. */
10839 vr_values::~vr_values ()
10841 /* Free allocated memory. */
10843 free (vr_phi_edge_counts
);
10844 bitmap_obstack_release (&vrp_equiv_obstack
);
10845 vrp_value_range_pool
.release ();
10847 /* So that we can distinguish between VRP data being available
10848 and not available. */
10850 vr_phi_edge_counts
= NULL
;
10853 /* Traverse all the blocks folding conditionals with known ranges. */
10856 vrp_prop::vrp_finalize (bool warn_array_bounds_p
)
10860 vr_values
.values_propagated
= true;
10864 fprintf (dump_file
, "\nValue ranges after VRP:\n\n");
10865 vr_values
.dump_all_value_ranges (dump_file
);
10866 fprintf (dump_file
, "\n");
10869 /* Set value range to non pointer SSA_NAMEs. */
10870 for (i
= 0; i
< num_ssa_names
; i
++)
10872 tree name
= ssa_name (i
);
10876 value_range
*vr
= get_value_range (name
);
10878 || (vr
->type
== VR_VARYING
)
10879 || (vr
->type
== VR_UNDEFINED
)
10880 || (TREE_CODE (vr
->min
) != INTEGER_CST
)
10881 || (TREE_CODE (vr
->max
) != INTEGER_CST
))
10884 if (POINTER_TYPE_P (TREE_TYPE (name
))
10885 && ((vr
->type
== VR_RANGE
10886 && range_includes_zero_p (vr
->min
, vr
->max
) == 0)
10887 || (vr
->type
== VR_ANTI_RANGE
10888 && range_includes_zero_p (vr
->min
, vr
->max
) == 1)))
10889 set_ptr_nonnull (name
);
10890 else if (!POINTER_TYPE_P (TREE_TYPE (name
)))
10891 set_range_info (name
, vr
->type
,
10892 wi::to_wide (vr
->min
),
10893 wi::to_wide (vr
->max
));
10896 class vrp_folder vrp_folder
;
10897 vrp_folder
.vr_values
= &vr_values
;
10898 vrp_folder
.substitute_and_fold ();
10900 if (warn_array_bounds
&& warn_array_bounds_p
)
10901 check_all_array_refs ();
10905 vr_values::set_vr_value (tree var
, value_range
*vr
)
10907 if (SSA_NAME_VERSION (var
) >= num_vr_values
)
10909 vr_value
[SSA_NAME_VERSION (var
)] = vr
;
10912 /* Main entry point to VRP (Value Range Propagation). This pass is
10913 loosely based on J. R. C. Patterson, ``Accurate Static Branch
10914 Prediction by Value Range Propagation,'' in SIGPLAN Conference on
10915 Programming Language Design and Implementation, pp. 67-78, 1995.
10916 Also available at http://citeseer.ist.psu.edu/patterson95accurate.html
10918 This is essentially an SSA-CCP pass modified to deal with ranges
10919 instead of constants.
10921 While propagating ranges, we may find that two or more SSA name
10922 have equivalent, though distinct ranges. For instance,
10925 2 p_4 = ASSERT_EXPR <p_3, p_3 != 0>
10927 4 p_5 = ASSERT_EXPR <p_4, p_4 == q_2>;
10931 In the code above, pointer p_5 has range [q_2, q_2], but from the
10932 code we can also determine that p_5 cannot be NULL and, if q_2 had
10933 a non-varying range, p_5's range should also be compatible with it.
10935 These equivalences are created by two expressions: ASSERT_EXPR and
10936 copy operations. Since p_5 is an assertion on p_4, and p_4 was the
10937 result of another assertion, then we can use the fact that p_5 and
10938 p_4 are equivalent when evaluating p_5's range.
10940 Together with value ranges, we also propagate these equivalences
10941 between names so that we can take advantage of information from
10942 multiple ranges when doing final replacement. Note that this
10943 equivalency relation is transitive but not symmetric.
10945 In the example above, p_5 is equivalent to p_4, q_2 and p_3, but we
10946 cannot assert that q_2 is equivalent to p_5 because q_2 may be used
10947 in contexts where that assertion does not hold (e.g., in line 6).
10949 TODO, the main difference between this pass and Patterson's is that
10950 we do not propagate edge probabilities. We only compute whether
10951 edges can be taken or not. That is, instead of having a spectrum
10952 of jump probabilities between 0 and 1, we only deal with 0, 1 and
10953 DON'T KNOW. In the future, it may be worthwhile to propagate
10954 probabilities to aid branch prediction. */
10956 static unsigned int
10957 execute_vrp (bool warn_array_bounds_p
)
10963 loop_optimizer_init (LOOPS_NORMAL
| LOOPS_HAVE_RECORDED_EXITS
);
10964 rewrite_into_loop_closed_ssa (NULL
, TODO_update_ssa
);
10965 scev_initialize ();
10967 /* ??? This ends up using stale EDGE_DFS_BACK for liveness computation.
10968 Inserting assertions may split edges which will invalidate
10970 insert_range_assertions ();
10972 to_remove_edges
.create (10);
10973 to_update_switch_stmts
.create (5);
10974 threadedge_initialize_values ();
10976 /* For visiting PHI nodes we need EDGE_DFS_BACK computed. */
10977 mark_dfs_back_edges ();
10979 class vrp_prop vrp_prop
;
10980 vrp_prop
.vrp_initialize ();
10981 vrp_prop
.ssa_propagate ();
10982 vrp_prop
.vrp_finalize (warn_array_bounds_p
);
10984 /* We must identify jump threading opportunities before we release
10985 the datastructures built by VRP. */
10986 identify_jump_threads (&vrp_prop
.vr_values
);
10988 /* A comparison of an SSA_NAME against a constant where the SSA_NAME
10989 was set by a type conversion can often be rewritten to use the
10990 RHS of the type conversion.
10992 However, doing so inhibits jump threading through the comparison.
10993 So that transformation is not performed until after jump threading
10996 FOR_EACH_BB_FN (bb
, cfun
)
10998 gimple
*last
= last_stmt (bb
);
10999 if (last
&& gimple_code (last
) == GIMPLE_COND
)
11000 vrp_prop
.vr_values
.simplify_cond_using_ranges_2 (as_a
<gcond
*> (last
));
11003 free_numbers_of_iterations_estimates (cfun
);
11005 /* ASSERT_EXPRs must be removed before finalizing jump threads
11006 as finalizing jump threads calls the CFG cleanup code which
11007 does not properly handle ASSERT_EXPRs. */
11008 remove_range_assertions ();
11010 /* If we exposed any new variables, go ahead and put them into
11011 SSA form now, before we handle jump threading. This simplifies
11012 interactions between rewriting of _DECL nodes into SSA form
11013 and rewriting SSA_NAME nodes into SSA form after block
11014 duplication and CFG manipulation. */
11015 update_ssa (TODO_update_ssa
);
11017 /* We identified all the jump threading opportunities earlier, but could
11018 not transform the CFG at that time. This routine transforms the
11019 CFG and arranges for the dominator tree to be rebuilt if necessary.
11021 Note the SSA graph update will occur during the normal TODO
11022 processing by the pass manager. */
11023 thread_through_all_blocks (false);
11025 /* Remove dead edges from SWITCH_EXPR optimization. This leaves the
11026 CFG in a broken state and requires a cfg_cleanup run. */
11027 FOR_EACH_VEC_ELT (to_remove_edges
, i
, e
)
11029 /* Update SWITCH_EXPR case label vector. */
11030 FOR_EACH_VEC_ELT (to_update_switch_stmts
, i
, su
)
11033 size_t n
= TREE_VEC_LENGTH (su
->vec
);
11035 gimple_switch_set_num_labels (su
->stmt
, n
);
11036 for (j
= 0; j
< n
; j
++)
11037 gimple_switch_set_label (su
->stmt
, j
, TREE_VEC_ELT (su
->vec
, j
));
11038 /* As we may have replaced the default label with a regular one
11039 make sure to make it a real default label again. This ensures
11040 optimal expansion. */
11041 label
= gimple_switch_label (su
->stmt
, 0);
11042 CASE_LOW (label
) = NULL_TREE
;
11043 CASE_HIGH (label
) = NULL_TREE
;
11046 if (to_remove_edges
.length () > 0)
11048 free_dominance_info (CDI_DOMINATORS
);
11049 loops_state_set (LOOPS_NEED_FIXUP
);
11052 to_remove_edges
.release ();
11053 to_update_switch_stmts
.release ();
11054 threadedge_finalize_values ();
11057 loop_optimizer_finalize ();
11063 const pass_data pass_data_vrp
=
11065 GIMPLE_PASS
, /* type */
11067 OPTGROUP_NONE
, /* optinfo_flags */
11068 TV_TREE_VRP
, /* tv_id */
11069 PROP_ssa
, /* properties_required */
11070 0, /* properties_provided */
11071 0, /* properties_destroyed */
11072 0, /* todo_flags_start */
11073 ( TODO_cleanup_cfg
| TODO_update_ssa
), /* todo_flags_finish */
11076 class pass_vrp
: public gimple_opt_pass
11079 pass_vrp (gcc::context
*ctxt
)
11080 : gimple_opt_pass (pass_data_vrp
, ctxt
), warn_array_bounds_p (false)
11083 /* opt_pass methods: */
11084 opt_pass
* clone () { return new pass_vrp (m_ctxt
); }
11085 void set_pass_param (unsigned int n
, bool param
)
11087 gcc_assert (n
== 0);
11088 warn_array_bounds_p
= param
;
11090 virtual bool gate (function
*) { return flag_tree_vrp
!= 0; }
11091 virtual unsigned int execute (function
*)
11092 { return execute_vrp (warn_array_bounds_p
); }
11095 bool warn_array_bounds_p
;
11096 }; // class pass_vrp
11098 } // anon namespace
11101 make_pass_vrp (gcc::context
*ctxt
)
11103 return new pass_vrp (ctxt
);