diff options
Diffstat (limited to 'gcc/tree-vrp.c')
| -rw-r--r-- | gcc/tree-vrp.c | 4972 |
1 files changed, 151 insertions, 4821 deletions
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c index f229c8983bf..b35033a4c2c 100644 --- a/gcc/tree-vrp.c +++ b/gcc/tree-vrp.c @@ -64,12 +64,7 @@ along with GCC; see the file COPYING3. If not see #include "tree-cfgcleanup.h" #include "stringpool.h" #include "attribs.h" - -#define VR_INITIALIZER { VR_UNDEFINED, NULL_TREE, NULL_TREE, NULL } - -/* Allocation pools for tree-vrp allocations. */ -static object_allocator<value_range> vrp_value_range_pool ("Tree VRP value ranges"); -static bitmap_obstack vrp_equiv_obstack; +#include "vr-values.h" /* Set of SSA names found live during the RPO traversal of the function for still active basic-blocks. */ @@ -84,28 +79,6 @@ live_on_edge (edge e, tree name) && bitmap_bit_p (live[e->dest->index], SSA_NAME_VERSION (name))); } -/* Local functions. */ -static int compare_values (tree val1, tree val2); -static int compare_values_warnv (tree val1, tree val2, bool *); -static tree vrp_evaluate_conditional_warnv_with_ops (enum tree_code, - tree, tree, bool, bool *, - bool *); - -struct assert_info -{ - /* Predicate code for the ASSERT_EXPR. Must be COMPARISON_CLASS_P. */ - enum tree_code comp_code; - - /* Name to register the assert for. */ - tree name; - - /* Value being compared against. */ - tree val; - - /* Expression to compare. */ - tree expr; -}; - /* Location information for ASSERT_EXPRs. Each instance of this structure describes an ASSERT_EXPR for an SSA name. Since a single SSA name may have more than one assertion associated with it, these @@ -145,29 +118,13 @@ static bitmap need_assert_for; ASSERT_EXPRs for SSA name N_I should be inserted. */ static assert_locus **asserts_for; -/* Value range array. After propagation, VR_VALUE[I] holds the range - of values that SSA name N_I may take. */ -static unsigned num_vr_values; -static value_range **vr_value; -static bool values_propagated; - -/* For a PHI node which sets SSA name N_I, VR_COUNTS[I] holds the - number of executable edges we saw the last time we visited the - node. */ -static int *vr_phi_edge_counts; - -struct switch_update { - gswitch *stmt; - tree vec; -}; - -static vec<edge> to_remove_edges; -static vec<switch_update> to_update_switch_stmts; +vec<edge> to_remove_edges; +vec<switch_update> to_update_switch_stmts; /* Return the maximum value for TYPE. */ -static inline tree +tree vrp_val_max (const_tree type) { if (!INTEGRAL_TYPE_P (type)) @@ -178,7 +135,7 @@ vrp_val_max (const_tree type) /* Return the minimum value for TYPE. */ -static inline tree +tree vrp_val_min (const_tree type) { if (!INTEGRAL_TYPE_P (type)) @@ -192,7 +149,7 @@ vrp_val_min (const_tree type) C typedefs and Ada subtypes can produce types whose TYPE_MAX_VALUE is not == to the integer constant with the same value in the type. */ -static inline bool +bool vrp_val_is_max (const_tree val) { tree type_max = vrp_val_max (TREE_TYPE (val)); @@ -203,7 +160,7 @@ vrp_val_is_max (const_tree val) /* Return whether VAL is equal to the minimum value of its type. */ -static inline bool +bool vrp_val_is_min (const_tree val) { tree type_min = vrp_val_min (TREE_TYPE (val)); @@ -224,10 +181,9 @@ set_value_range_to_undefined (value_range *vr) bitmap_clear (vr->equiv); } - /* Set value range VR to VR_VARYING. */ -static inline void +void set_value_range_to_varying (value_range *vr) { vr->type = VR_VARYING; @@ -236,10 +192,9 @@ set_value_range_to_varying (value_range *vr) bitmap_clear (vr->equiv); } - /* Set value range VR to {T, MIN, MAX, EQUIV}. */ -static void +void set_value_range (value_range *vr, enum value_range_type t, tree min, tree max, bitmap equiv) { @@ -272,10 +227,13 @@ set_value_range (value_range *vr, enum value_range_type t, tree min, vr->max = max; /* Since updating the equivalence set involves deep copying the - bitmaps, only do it if absolutely necessary. */ + bitmaps, only do it if absolutely necessary. + + All equivalence bitmaps are allocated from the same obstack. So + we can use the obstack associated with EQUIV to allocate vr->equiv. */ if (vr->equiv == NULL && equiv != NULL) - vr->equiv = BITMAP_ALLOC (&vrp_equiv_obstack); + vr->equiv = BITMAP_ALLOC (equiv->obstack); if (equiv != vr->equiv) { @@ -296,7 +254,7 @@ set_value_range (value_range *vr, enum value_range_type t, tree min, This routine exists to ease canonicalization in the case where we extract ranges from var + CST op limit. */ -static void +void set_and_canonicalize_value_range (value_range *vr, enum value_range_type t, tree min, tree max, bitmap equiv) { @@ -404,7 +362,7 @@ set_and_canonicalize_value_range (value_range *vr, enum value_range_type t, /* Copy value range FROM into value range TO. */ -static inline void +void copy_value_range (value_range *to, value_range *from) { set_value_range (to, from->type, from->min, from->max, from->equiv); @@ -414,7 +372,7 @@ copy_value_range (value_range *to, value_range *from) with values we get from statements, and exists to clear the TREE_OVERFLOW flag. */ -static inline void +void set_value_range_to_value (value_range *vr, tree val, bitmap equiv) { gcc_assert (is_gimple_min_invariant (val)); @@ -423,18 +381,9 @@ set_value_range_to_value (value_range *vr, tree val, bitmap equiv) set_value_range (vr, VR_RANGE, val, val, equiv); } -/* Set value range VR to a non-negative range of type TYPE. */ - -static inline void -set_value_range_to_nonnegative (value_range *vr, tree type) -{ - tree zero = build_int_cst (type, 0); - set_value_range (vr, VR_RANGE, zero, vrp_val_max (type), vr->equiv); -} - /* Set value range VR to a non-NULL range of type TYPE. */ -static inline void +void set_value_range_to_nonnull (value_range *vr, tree type) { tree zero = build_int_cst (type, 0); @@ -444,27 +393,13 @@ set_value_range_to_nonnull (value_range *vr, tree type) /* Set value range VR to a NULL range of type TYPE. */ -static inline void +void set_value_range_to_null (value_range *vr, tree type) { set_value_range_to_value (vr, build_int_cst (type, 0), vr->equiv); } -/* Set value range VR to a range of a truthvalue of type TYPE. */ - -static inline void -set_value_range_to_truthvalue (value_range *vr, tree type) -{ - if (TYPE_PRECISION (type) == 1) - set_value_range_to_varying (vr); - else - set_value_range (vr, VR_RANGE, - build_int_cst (type, 0), build_int_cst (type, 1), - vr->equiv); -} - - /* If abs (min) < abs (max), set VR to [-max, max], if abs (min) >= abs (max), set VR to [-min, min]. */ @@ -500,103 +435,9 @@ abs_extent_range (value_range *vr, tree min, tree max) set_and_canonicalize_value_range (vr, VR_RANGE, min, max, NULL); } - -/* Return value range information for VAR. - - If we have no values ranges recorded (ie, VRP is not running), then - return NULL. Otherwise create an empty range if none existed for VAR. */ - -static value_range * -get_value_range (const_tree var) -{ - static const value_range vr_const_varying - = { VR_VARYING, NULL_TREE, NULL_TREE, NULL }; - value_range *vr; - tree sym; - unsigned ver = SSA_NAME_VERSION (var); - - /* If we have no recorded ranges, then return NULL. */ - if (! vr_value) - return NULL; - - /* If we query the range for a new SSA name return an unmodifiable VARYING. - We should get here at most from the substitute-and-fold stage which - will never try to change values. */ - if (ver >= num_vr_values) - return CONST_CAST (value_range *, &vr_const_varying); - - vr = vr_value[ver]; - if (vr) - return vr; - - /* After propagation finished do not allocate new value-ranges. */ - if (values_propagated) - return CONST_CAST (value_range *, &vr_const_varying); - - /* Create a default value range. */ - vr_value[ver] = vr = vrp_value_range_pool.allocate (); - memset (vr, 0, sizeof (*vr)); - - /* Defer allocating the equivalence set. */ - vr->equiv = NULL; - - /* If VAR is a default definition of a parameter, the variable can - take any value in VAR's type. */ - if (SSA_NAME_IS_DEFAULT_DEF (var)) - { - sym = SSA_NAME_VAR (var); - if (TREE_CODE (sym) == PARM_DECL) - { - /* Try to use the "nonnull" attribute to create ~[0, 0] - anti-ranges for pointers. Note that this is only valid with - default definitions of PARM_DECLs. */ - if (POINTER_TYPE_P (TREE_TYPE (sym)) - && (nonnull_arg_p (sym) - || get_ptr_nonnull (var))) - set_value_range_to_nonnull (vr, TREE_TYPE (sym)); - else if (INTEGRAL_TYPE_P (TREE_TYPE (sym))) - { - wide_int min, max; - value_range_type rtype = get_range_info (var, &min, &max); - if (rtype == VR_RANGE || rtype == VR_ANTI_RANGE) - set_value_range (vr, rtype, - wide_int_to_tree (TREE_TYPE (var), min), - wide_int_to_tree (TREE_TYPE (var), max), - NULL); - else - set_value_range_to_varying (vr); - } - else - set_value_range_to_varying (vr); - } - else if (TREE_CODE (sym) == RESULT_DECL - && DECL_BY_REFERENCE (sym)) - set_value_range_to_nonnull (vr, TREE_TYPE (sym)); - } - - return vr; -} - -/* Set value-ranges of all SSA names defined by STMT to varying. */ - -static void -set_defs_to_varying (gimple *stmt) -{ - ssa_op_iter i; - tree def; - FOR_EACH_SSA_TREE_OPERAND (def, stmt, i, SSA_OP_DEF) - { - value_range *vr = get_value_range (def); - /* Avoid writing to vr_const_varying get_value_range may return. */ - if (vr->type != VR_VARYING) - set_value_range_to_varying (vr); - } -} - - /* Return true, if VAL1 and VAL2 are equal values for VRP purposes. */ -static inline bool +bool vrp_operand_equal_p (const_tree val1, const_tree val2) { if (val1 == val2) @@ -608,7 +449,7 @@ vrp_operand_equal_p (const_tree val1, const_tree val2) /* Return true, if the bitmaps B1 and B2 are equal. */ -static inline bool +bool vrp_bitmap_equal_p (const_bitmap b1, const_bitmap b2) { return (b1 == b2 @@ -618,92 +459,9 @@ vrp_bitmap_equal_p (const_bitmap b1, const_bitmap b2) && bitmap_equal_p (b1, b2))); } -/* Update the value range and equivalence set for variable VAR to - NEW_VR. Return true if NEW_VR is different from VAR's previous - value. - - NOTE: This function assumes that NEW_VR is a temporary value range - object created for the sole purpose of updating VAR's range. The - storage used by the equivalence set from NEW_VR will be freed by - this function. Do not call update_value_range when NEW_VR - is the range object associated with another SSA name. */ - -static inline bool -update_value_range (const_tree var, value_range *new_vr) -{ - value_range *old_vr; - bool is_new; - - /* If there is a value-range on the SSA name from earlier analysis - factor that in. */ - if (INTEGRAL_TYPE_P (TREE_TYPE (var))) - { - wide_int min, max; - value_range_type rtype = get_range_info (var, &min, &max); - if (rtype == VR_RANGE || rtype == VR_ANTI_RANGE) - { - tree nr_min, nr_max; - nr_min = wide_int_to_tree (TREE_TYPE (var), min); - nr_max = wide_int_to_tree (TREE_TYPE (var), max); - value_range nr = VR_INITIALIZER; - set_and_canonicalize_value_range (&nr, rtype, nr_min, nr_max, NULL); - vrp_intersect_ranges (new_vr, &nr); - } - } - - /* Update the value range, if necessary. */ - old_vr = get_value_range (var); - is_new = old_vr->type != new_vr->type - || !vrp_operand_equal_p (old_vr->min, new_vr->min) - || !vrp_operand_equal_p (old_vr->max, new_vr->max) - || !vrp_bitmap_equal_p (old_vr->equiv, new_vr->equiv); - - if (is_new) - { - /* Do not allow transitions up the lattice. The following - is slightly more awkward than just new_vr->type < old_vr->type - because VR_RANGE and VR_ANTI_RANGE need to be considered - the same. We may not have is_new when transitioning to - UNDEFINED. If old_vr->type is VARYING, we shouldn't be - called. */ - if (new_vr->type == VR_UNDEFINED) - { - BITMAP_FREE (new_vr->equiv); - set_value_range_to_varying (old_vr); - set_value_range_to_varying (new_vr); - return true; - } - else - set_value_range (old_vr, new_vr->type, new_vr->min, new_vr->max, - new_vr->equiv); - } - - BITMAP_FREE (new_vr->equiv); - - return is_new; -} - - -/* Add VAR and VAR's equivalence set to EQUIV. This is the central - point where equivalence processing can be turned on/off. */ - -static void -add_equivalence (bitmap *equiv, const_tree var) -{ - unsigned ver = SSA_NAME_VERSION (var); - value_range *vr = get_value_range (var); - - if (*equiv == NULL) - *equiv = BITMAP_ALLOC (&vrp_equiv_obstack); - bitmap_set_bit (*equiv, ver); - if (vr && vr->equiv) - bitmap_ior_into (*equiv, vr->equiv); -} - - /* Return true if VR is ~[0, 0]. */ -static inline bool +bool range_is_nonnull (value_range *vr) { return vr->type == VR_ANTI_RANGE @@ -725,7 +483,7 @@ range_is_null (value_range *vr) /* Return true if max and min of VR are INTEGER_CST. It's not necessary a singleton. */ -static inline bool +bool range_int_cst_p (value_range *vr) { return (vr->type == VR_RANGE @@ -735,7 +493,7 @@ range_int_cst_p (value_range *vr) /* Return true if VR is a INTEGER_CST singleton. */ -static inline bool +bool range_int_cst_singleton_p (value_range *vr) { return (range_int_cst_p (vr) @@ -744,7 +502,7 @@ range_int_cst_singleton_p (value_range *vr) /* Return true if value range VR involves at least one symbol. */ -static inline bool +bool symbolic_range_p (value_range *vr) { return (!is_gimple_min_invariant (vr->min) @@ -755,7 +513,7 @@ symbolic_range_p (value_range *vr) otherwise. We only handle additive operations and set NEG to true if the symbol is negated and INV to the invariant part, if any. */ -static tree +tree get_single_symbol (tree t, bool *neg, tree *inv) { bool neg_; @@ -824,161 +582,11 @@ build_symbolic_expr (tree type, tree sym, bool neg, tree inv) return build2 (pointer_p ? POINTER_PLUS_EXPR : PLUS_EXPR, type, t, inv); } -/* Return true if value range VR involves exactly one symbol SYM. */ - -static bool -symbolic_range_based_on_p (value_range *vr, const_tree sym) -{ - bool neg, min_has_symbol, max_has_symbol; - tree inv; - - if (is_gimple_min_invariant (vr->min)) - min_has_symbol = false; - else if (get_single_symbol (vr->min, &neg, &inv) == sym) - min_has_symbol = true; - else - return false; - - if (is_gimple_min_invariant (vr->max)) - max_has_symbol = false; - else if (get_single_symbol (vr->max, &neg, &inv) == sym) - max_has_symbol = true; - else - return false; - - return (min_has_symbol || max_has_symbol); -} - -/* Return true if the result of assignment STMT is know to be non-zero. */ - -static bool -gimple_assign_nonzero_p (gimple *stmt) -{ - enum tree_code code = gimple_assign_rhs_code (stmt); - bool strict_overflow_p; - switch (get_gimple_rhs_class (code)) - { - case GIMPLE_UNARY_RHS: - return tree_unary_nonzero_warnv_p (gimple_assign_rhs_code (stmt), - gimple_expr_type (stmt), - gimple_assign_rhs1 (stmt), - &strict_overflow_p); - case GIMPLE_BINARY_RHS: - return tree_binary_nonzero_warnv_p (gimple_assign_rhs_code (stmt), - gimple_expr_type (stmt), - gimple_assign_rhs1 (stmt), - gimple_assign_rhs2 (stmt), - &strict_overflow_p); - case GIMPLE_TERNARY_RHS: - return false; - case GIMPLE_SINGLE_RHS: - return tree_single_nonzero_warnv_p (gimple_assign_rhs1 (stmt), - &strict_overflow_p); - case GIMPLE_INVALID_RHS: - gcc_unreachable (); - default: - gcc_unreachable (); - } -} - -/* Return true if STMT is known to compute a non-zero value. */ - -static bool -gimple_stmt_nonzero_p (gimple *stmt) -{ - switch (gimple_code (stmt)) - { - case GIMPLE_ASSIGN: - return gimple_assign_nonzero_p (stmt); - case GIMPLE_CALL: - { - tree fndecl = gimple_call_fndecl (stmt); - if (!fndecl) return false; - if (flag_delete_null_pointer_checks && !flag_check_new - && DECL_IS_OPERATOR_NEW (fndecl) - && !TREE_NOTHROW (fndecl)) - return true; - /* References are always non-NULL. */ - if (flag_delete_null_pointer_checks - && TREE_CODE (TREE_TYPE (fndecl)) == REFERENCE_TYPE) - return true; - if (flag_delete_null_pointer_checks && - lookup_attribute ("returns_nonnull", - TYPE_ATTRIBUTES (gimple_call_fntype (stmt)))) - return true; - - gcall *call_stmt = as_a<gcall *> (stmt); - unsigned rf = gimple_call_return_flags (call_stmt); - if (rf & ERF_RETURNS_ARG) - { - unsigned argnum = rf & ERF_RETURN_ARG_MASK; - if (argnum < gimple_call_num_args (call_stmt)) - { - tree arg = gimple_call_arg (call_stmt, argnum); - if (SSA_VAR_P (arg) - && infer_nonnull_range_by_attribute (stmt, arg)) - return true; - } - } - return gimple_alloca_call_p (stmt); - } - default: - gcc_unreachable (); - } -} - -/* Like tree_expr_nonzero_p, but this function uses value ranges - obtained so far. */ - -static bool -vrp_stmt_computes_nonzero (gimple *stmt) -{ - if (gimple_stmt_nonzero_p (stmt)) - return true; - - /* If we have an expression of the form &X->a, then the expression - is nonnull if X is nonnull. */ - if (is_gimple_assign (stmt) - && gimple_assign_rhs_code (stmt) == ADDR_EXPR) - { - tree expr = gimple_assign_rhs1 (stmt); - tree base = get_base_address (TREE_OPERAND (expr, 0)); - - if (base != NULL_TREE - && TREE_CODE (base) == MEM_REF - && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME) - { - value_range *vr = get_value_range (TREE_OPERAND (base, 0)); - if (range_is_nonnull (vr)) - return true; - } - } - - return false; -} - -/* Returns true if EXPR is a valid value (as expected by compare_values) -- - a gimple invariant, or SSA_NAME +- CST. */ - -static bool -valid_value_p (tree expr) -{ - if (TREE_CODE (expr) == SSA_NAME) - return true; - - if (TREE_CODE (expr) == PLUS_EXPR - || TREE_CODE (expr) == MINUS_EXPR) - return (TREE_CODE (TREE_OPERAND (expr, 0)) == SSA_NAME - && TREE_CODE (TREE_OPERAND (expr, 1)) == INTEGER_CST); - - return is_gimple_min_invariant (expr); -} - /* Return 1 if VAL < VAL2 0 if !(VAL < VAL2) -2 if those are incomparable. */ -static inline int +int operand_less_p (tree val, tree val2) { /* LT is folded faster than GE and others. Inline the common case. */ @@ -1020,7 +628,7 @@ operand_less_p (tree val, tree val2) true if the return value is only valid if we assume that signed overflow is undefined. */ -static int +int compare_values_warnv (tree val1, tree val2, bool *strict_overflow_p) { if (val1 == val2) @@ -1174,7 +782,7 @@ compare_values_warnv (tree val1, tree val2, bool *strict_overflow_p) /* Compare values like compare_values_warnv. */ -static int +int compare_values (tree val1, tree val2) { bool sop; @@ -1189,7 +797,7 @@ compare_values (tree val1, tree val2) Benchmark compile/20001226-1.c compilation time after changing this function. */ -static inline int +int value_inside_range (tree val, tree min, tree max) { int cmp1, cmp2; @@ -1232,7 +840,7 @@ value_ranges_intersect_p (value_range *vr0, value_range *vr1) /* Return 1 if [MIN, MAX] includes the value zero, 0 if it does not include the value zero, -2 if we cannot tell. */ -static inline int +int range_includes_zero_p (tree min, tree max) { tree zero = build_int_cst (TREE_TYPE (min), 0); @@ -1259,7 +867,7 @@ value_range_nonnegative_p (value_range *vr) /* If *VR has a value rante that is a single constant value return that, otherwise return NULL_TREE. */ -static tree +tree value_range_constant_singleton (value_range *vr) { if (vr->type == VR_RANGE @@ -1270,355 +878,6 @@ value_range_constant_singleton (value_range *vr) return NULL_TREE; } -/* If OP has a value range with a single constant value return that, - otherwise return NULL_TREE. This returns OP itself if OP is a - constant. */ - -static tree -op_with_constant_singleton_value_range (tree op) -{ - if (is_gimple_min_invariant (op)) - return op; - - if (TREE_CODE (op) != SSA_NAME) - return NULL_TREE; - - return value_range_constant_singleton (get_value_range (op)); -} - -/* Return true if op is in a boolean [0, 1] value-range. */ - -static bool -op_with_boolean_value_range_p (tree op) -{ - value_range *vr; - - if (TYPE_PRECISION (TREE_TYPE (op)) == 1) - return true; - - if (integer_zerop (op) - || integer_onep (op)) - return true; - - if (TREE_CODE (op) != SSA_NAME) - return false; - - vr = get_value_range (op); - return (vr->type == VR_RANGE - && integer_zerop (vr->min) - && integer_onep (vr->max)); -} - -/* Extract value range information for VAR when (OP COND_CODE LIMIT) is - true and store it in *VR_P. */ - -static void -extract_range_for_var_from_comparison_expr (tree var, enum tree_code cond_code, - tree op, tree limit, - value_range *vr_p) -{ - tree min, max, type; - value_range *limit_vr; - type = TREE_TYPE (var); - gcc_assert (limit != var); - - /* For pointer arithmetic, we only keep track of pointer equality - and inequality. */ - if (POINTER_TYPE_P (type) && cond_code != NE_EXPR && cond_code != EQ_EXPR) - { - set_value_range_to_varying (vr_p); - return; - } - - /* If LIMIT is another SSA name and LIMIT has a range of its own, - try to use LIMIT's range to avoid creating symbolic ranges - unnecessarily. */ - limit_vr = (TREE_CODE (limit) == SSA_NAME) ? get_value_range (limit) : NULL; - - /* LIMIT's range is only interesting if it has any useful information. */ - if (! limit_vr - || limit_vr->type == VR_UNDEFINED - || limit_vr->type == VR_VARYING - || (symbolic_range_p (limit_vr) - && ! (limit_vr->type == VR_RANGE - && (limit_vr->min == limit_vr->max - || operand_equal_p (limit_vr->min, limit_vr->max, 0))))) - limit_vr = NULL; - - /* Initially, the new range has the same set of equivalences of - VAR's range. This will be revised before returning the final - value. Since assertions may be chained via mutually exclusive - predicates, we will need to trim the set of equivalences before - we are done. */ - gcc_assert (vr_p->equiv == NULL); - add_equivalence (&vr_p->equiv, var); - - /* Extract a new range based on the asserted comparison for VAR and - LIMIT's value range. Notice that if LIMIT has an anti-range, we - will only use it for equality comparisons (EQ_EXPR). For any - other kind of assertion, we cannot derive a range from LIMIT's - anti-range that can be used to describe the new range. For - instance, ASSERT_EXPR <x_2, x_2 <= b_4>. If b_4 is ~[2, 10], - then b_4 takes on the ranges [-INF, 1] and [11, +INF]. There is - no single range for x_2 that could describe LE_EXPR, so we might - as well build the range [b_4, +INF] for it. - One special case we handle is extracting a range from a - range test encoded as (unsigned)var + CST <= limit. */ - if (TREE_CODE (op) == NOP_EXPR - || TREE_CODE (op) == PLUS_EXPR) - { - if (TREE_CODE (op) == PLUS_EXPR) - { - min = fold_build1 (NEGATE_EXPR, TREE_TYPE (TREE_OPERAND (op, 1)), - TREE_OPERAND (op, 1)); - max = int_const_binop (PLUS_EXPR, limit, min); - op = TREE_OPERAND (op, 0); - } - else - { - min = build_int_cst (TREE_TYPE (var), 0); - max = limit; - } - - /* Make sure to not set TREE_OVERFLOW on the final type - conversion. We are willingly interpreting large positive - unsigned values as negative signed values here. */ - min = force_fit_type (TREE_TYPE (var), wi::to_widest (min), 0, false); - max = force_fit_type (TREE_TYPE (var), wi::to_widest (max), 0, false); - - /* We can transform a max, min range to an anti-range or - vice-versa. Use set_and_canonicalize_value_range which does - this for us. */ - if (cond_code == LE_EXPR) - set_and_canonicalize_value_range (vr_p, VR_RANGE, - min, max, vr_p->equiv); - else if (cond_code == GT_EXPR) - set_and_canonicalize_value_range (vr_p, VR_ANTI_RANGE, - min, max, vr_p->equiv); - else - gcc_unreachable (); - } - else if (cond_code == EQ_EXPR) - { - enum value_range_type range_type; - - if (limit_vr) - { - range_type = limit_vr->type; - min = limit_vr->min; - max = limit_vr->max; - } - else - { - range_type = VR_RANGE; - min = limit; - max = limit; - } - - set_value_range (vr_p, range_type, min, max, vr_p->equiv); - - /* When asserting the equality VAR == LIMIT and LIMIT is another - SSA name, the new range will also inherit the equivalence set - from LIMIT. */ - if (TREE_CODE (limit) == SSA_NAME) - add_equivalence (&vr_p->equiv, limit); - } - else if (cond_code == NE_EXPR) - { - /* As described above, when LIMIT's range is an anti-range and - this assertion is an inequality (NE_EXPR), then we cannot - derive anything from the anti-range. For instance, if - LIMIT's range was ~[0, 0], the assertion 'VAR != LIMIT' does - not imply that VAR's range is [0, 0]. So, in the case of - anti-ranges, we just assert the inequality using LIMIT and - not its anti-range. - - If LIMIT_VR is a range, we can only use it to build a new - anti-range if LIMIT_VR is a single-valued range. For - instance, if LIMIT_VR is [0, 1], the predicate - VAR != [0, 1] does not mean that VAR's range is ~[0, 1]. - Rather, it means that for value 0 VAR should be ~[0, 0] - and for value 1, VAR should be ~[1, 1]. We cannot - represent these ranges. - - The only situation in which we can build a valid - anti-range is when LIMIT_VR is a single-valued range - (i.e., LIMIT_VR->MIN == LIMIT_VR->MAX). In that case, - build the anti-range ~[LIMIT_VR->MIN, LIMIT_VR->MAX]. */ - if (limit_vr - && limit_vr->type == VR_RANGE - && compare_values (limit_vr->min, limit_vr->max) == 0) - { - min = limit_vr->min; - max = limit_vr->max; - } - else - { - /* In any other case, we cannot use LIMIT's range to build a - valid anti-range. */ - min = max = limit; - } - - /* If MIN and MAX cover the whole range for their type, then - just use the original LIMIT. */ - if (INTEGRAL_TYPE_P (type) - && vrp_val_is_min (min) - && vrp_val_is_max (max)) - min = max = limit; - - set_and_canonicalize_value_range (vr_p, VR_ANTI_RANGE, - min, max, vr_p->equiv); - } - else if (cond_code == LE_EXPR || cond_code == LT_EXPR) - { - min = TYPE_MIN_VALUE (type); - - if (limit_vr == NULL || limit_vr->type == VR_ANTI_RANGE) - max = limit; - else - { - /* If LIMIT_VR is of the form [N1, N2], we need to build the - range [MIN, N2] for LE_EXPR and [MIN, N2 - 1] for - LT_EXPR. */ - max = limit_vr->max; - } - - /* If the maximum value forces us to be out of bounds, simply punt. - It would be pointless to try and do anything more since this - all should be optimized away above us. */ - if (cond_code == LT_EXPR - && compare_values (max, min) == 0) - set_value_range_to_varying (vr_p); - else - { - /* For LT_EXPR, we create the range [MIN, MAX - 1]. */ - if (cond_code == LT_EXPR) - { - if (TYPE_PRECISION (TREE_TYPE (max)) == 1 - && !TYPE_UNSIGNED (TREE_TYPE (max))) - max = fold_build2 (PLUS_EXPR, TREE_TYPE (max), max, - build_int_cst (TREE_TYPE (max), -1)); - else - max = fold_build2 (MINUS_EXPR, TREE_TYPE (max), max, - build_int_cst (TREE_TYPE (max), 1)); - /* Signal to compare_values_warnv this expr doesn't overflow. */ - if (EXPR_P (max)) - TREE_NO_WARNING (max) = 1; - } - - set_value_range (vr_p, VR_RANGE, min, max, vr_p->equiv); - } - } - else if (cond_code == GE_EXPR || cond_code == GT_EXPR) - { - max = TYPE_MAX_VALUE (type); - - if (limit_vr == NULL || limit_vr->type == VR_ANTI_RANGE) - min = limit; - else - { - /* If LIMIT_VR is of the form [N1, N2], we need to build the - range [N1, MAX] for GE_EXPR and [N1 + 1, MAX] for - GT_EXPR. */ - min = limit_vr->min; - } - - /* If the minimum value forces us to be out of bounds, simply punt. - It would be pointless to try and do anything more since this - all should be optimized away above us. */ - if (cond_code == GT_EXPR - && compare_values (min, max) == 0) - set_value_range_to_varying (vr_p); - else - { - /* For GT_EXPR, we create the range [MIN + 1, MAX]. */ - if (cond_code == GT_EXPR) - { - if (TYPE_PRECISION (TREE_TYPE (min)) == 1 - && !TYPE_UNSIGNED (TREE_TYPE (min))) - min = fold_build2 (MINUS_EXPR, TREE_TYPE (min), min, - build_int_cst (TREE_TYPE (min), -1)); - else - min = fold_build2 (PLUS_EXPR, TREE_TYPE (min), min, - build_int_cst (TREE_TYPE (min), 1)); - /* Signal to compare_values_warnv this expr doesn't overflow. */ - if (EXPR_P (min)) - TREE_NO_WARNING (min) = 1; - } - - set_value_range (vr_p, VR_RANGE, min, max, vr_p->equiv); - } - } - else - gcc_unreachable (); - - /* Finally intersect the new range with what we already know about var. */ - vrp_intersect_ranges (vr_p, get_value_range (var)); -} - -/* Extract value range information from an ASSERT_EXPR EXPR and store - it in *VR_P. */ - -static void -extract_range_from_assert (value_range *vr_p, tree expr) -{ - tree var = ASSERT_EXPR_VAR (expr); - tree cond = ASSERT_EXPR_COND (expr); - tree limit, op; - enum tree_code cond_code; - gcc_assert (COMPARISON_CLASS_P (cond)); - - /* Find VAR in the ASSERT_EXPR conditional. */ - if (var == TREE_OPERAND (cond, 0) - || TREE_CODE (TREE_OPERAND (cond, 0)) == PLUS_EXPR - || TREE_CODE (TREE_OPERAND (cond, 0)) == NOP_EXPR) - { - /* If the predicate is of the form VAR COMP LIMIT, then we just - take LIMIT from the RHS and use the same comparison code. */ - cond_code = TREE_CODE (cond); - limit = TREE_OPERAND (cond, 1); - op = TREE_OPERAND (cond, 0); - } - else - { - /* If the predicate is of the form LIMIT COMP VAR, then we need - to flip around the comparison code to create the proper range - for VAR. */ - cond_code = swap_tree_comparison (TREE_CODE (cond)); - limit = TREE_OPERAND (cond, 0); - op = TREE_OPERAND (cond, 1); - } - extract_range_for_var_from_comparison_expr (var, cond_code, op, - limit, vr_p); -} - -/* Extract range information from SSA name VAR and store it in VR. If - VAR has an interesting range, use it. Otherwise, create the - range [VAR, VAR] and return it. This is useful in situations where - we may have conditionals testing values of VARYING names. For - instance, - - x_3 = y_5; - if (x_3 > y_5) - ... - - Even if y_5 is deemed VARYING, we can determine that x_3 > y_5 is - always false. */ - -static void -extract_range_from_ssa_name (value_range *vr, tree var) -{ - value_range *var_vr = get_value_range (var); - - if (var_vr->type != VR_VARYING) - copy_value_range (vr, var_vr); - else - set_value_range (vr, VR_RANGE, var, var, NULL); - - add_equivalence (&vr->equiv, var); -} - - /* Wrapper around int_const_binop. Return true if we can compute the result; i.e. if the operation doesn't overflow or if the overflow is undefined. In the latter case (if the operation overflows and @@ -1752,7 +1011,7 @@ vrp_int_const_binop (enum tree_code code, tree val1, tree val2, wide_int *res) bitmask if some bit is set, it means for all numbers in the range the bit is 1, otherwise it might be 0 or 1. */ -static bool +bool zero_nonzero_bits_from_vr (const tree expr_type, value_range *vr, wide_int *may_be_nonzero, @@ -1942,7 +1201,7 @@ extract_range_from_multiplicative_op_1 (value_range *vr, the ranges of each of its operands *VR0 and *VR1 with resulting type EXPR_TYPE. The resulting range is stored in *VR. */ -static void +void extract_range_from_binary_expr_1 (value_range *vr, enum tree_code code, tree expr_type, value_range *vr0_, value_range *vr1_) @@ -3037,105 +2296,6 @@ extract_range_from_binary_expr_1 (value_range *vr, set_value_range (vr, type, min, max, NULL); } -/* Extract range information from a binary expression OP0 CODE OP1 based on - the ranges of each of its operands with resulting type EXPR_TYPE. - The resulting range is stored in *VR. */ - -static void -extract_range_from_binary_expr (value_range *vr, - enum tree_code code, - tree expr_type, tree op0, tree op1) -{ - value_range vr0 = VR_INITIALIZER; - value_range vr1 = VR_INITIALIZER; - - /* Get value ranges for each operand. For constant operands, create - a new value range with the operand to simplify processing. */ - if (TREE_CODE (op0) == SSA_NAME) - vr0 = *(get_value_range (op0)); - else if (is_gimple_min_invariant (op0)) - set_value_range_to_value (&vr0, op0, NULL); - else - set_value_range_to_varying (&vr0); - - if (TREE_CODE (op1) == SSA_NAME) - vr1 = *(get_value_range (op1)); - else if (is_gimple_min_invariant (op1)) - set_value_range_to_value (&vr1, op1, NULL); - else - set_value_range_to_varying (&vr1); - - extract_range_from_binary_expr_1 (vr, code, expr_type, &vr0, &vr1); - - /* Try harder for PLUS and MINUS if the range of one operand is symbolic - and based on the other operand, for example if it was deduced from a - symbolic comparison. When a bound of the range of the first operand - is invariant, we set the corresponding bound of the new range to INF - in order to avoid recursing on the range of the second operand. */ - if (vr->type == VR_VARYING - && (code == PLUS_EXPR || code == MINUS_EXPR) - && TREE_CODE (op1) == SSA_NAME - && vr0.type == VR_RANGE - && symbolic_range_based_on_p (&vr0, op1)) - { - const bool minus_p = (code == MINUS_EXPR); - value_range n_vr1 = VR_INITIALIZER; - - /* Try with VR0 and [-INF, OP1]. */ - if (is_gimple_min_invariant (minus_p ? vr0.max : vr0.min)) - set_value_range (&n_vr1, VR_RANGE, vrp_val_min (expr_type), op1, NULL); - - /* Try with VR0 and [OP1, +INF]. */ - else if (is_gimple_min_invariant (minus_p ? vr0.min : vr0.max)) - set_value_range (&n_vr1, VR_RANGE, op1, vrp_val_max (expr_type), NULL); - - /* Try with VR0 and [OP1, OP1]. */ - else - set_value_range (&n_vr1, VR_RANGE, op1, op1, NULL); - - extract_range_from_binary_expr_1 (vr, code, expr_type, &vr0, &n_vr1); - } - - if (vr->type == VR_VARYING - && (code == PLUS_EXPR || code == MINUS_EXPR) - && TREE_CODE (op0) == SSA_NAME - && vr1.type == VR_RANGE - && symbolic_range_based_on_p (&vr1, op0)) - { - const bool minus_p = (code == MINUS_EXPR); - value_range n_vr0 = VR_INITIALIZER; - - /* Try with [-INF, OP0] and VR1. */ - if (is_gimple_min_invariant (minus_p ? vr1.max : vr1.min)) - set_value_range (&n_vr0, VR_RANGE, vrp_val_min (expr_type), op0, NULL); - - /* Try with [OP0, +INF] and VR1. */ - else if (is_gimple_min_invariant (minus_p ? vr1.min : vr1.max)) - set_value_range (&n_vr0, VR_RANGE, op0, vrp_val_max (expr_type), NULL); - - /* Try with [OP0, OP0] and VR1. */ - else - set_value_range (&n_vr0, VR_RANGE, op0, op0, NULL); - - extract_range_from_binary_expr_1 (vr, code, expr_type, &n_vr0, &vr1); - } - - /* If we didn't derive a range for MINUS_EXPR, and - op1's range is ~[op0,op0] or vice-versa, then we - can derive a non-null range. This happens often for - pointer subtraction. */ - if (vr->type == VR_VARYING - && code == MINUS_EXPR - && TREE_CODE (op0) == SSA_NAME - && ((vr0.type == VR_ANTI_RANGE - && vr0.min == op1 - && vr0.min == vr0.max) - || (vr1.type == VR_ANTI_RANGE - && vr1.min == op0 - && vr1.min == vr1.max))) - set_value_range_to_nonnull (vr, TREE_TYPE (op0)); -} - /* Extract range information from a unary operation CODE based on the range of its operand *VR0 with type OP0_TYPE with resulting type TYPE. The resulting range is stored in *VR. */ @@ -3383,1040 +2543,11 @@ extract_range_from_unary_expr (value_range *vr, return; } - -/* Extract range information from a unary expression CODE OP0 based on - the range of its operand with resulting type TYPE. - The resulting range is stored in *VR. */ - -static void -extract_range_from_unary_expr (value_range *vr, enum tree_code code, - tree type, tree op0) -{ - value_range vr0 = VR_INITIALIZER; - - /* Get value ranges for the operand. For constant operands, create - a new value range with the operand to simplify processing. */ - if (TREE_CODE (op0) == SSA_NAME) - vr0 = *(get_value_range (op0)); - else if (is_gimple_min_invariant (op0)) - set_value_range_to_value (&vr0, op0, NULL); - else - set_value_range_to_varying (&vr0); - - extract_range_from_unary_expr (vr, code, type, &vr0, TREE_TYPE (op0)); -} - - -/* Extract range information from a conditional expression STMT based on - the ranges of each of its operands and the expression code. */ - -static void -extract_range_from_cond_expr (value_range *vr, gassign *stmt) -{ - tree op0, op1; - value_range vr0 = VR_INITIALIZER; - value_range vr1 = VR_INITIALIZER; - - /* Get value ranges for each operand. For constant operands, create - a new value range with the operand to simplify processing. */ - op0 = gimple_assign_rhs2 (stmt); - if (TREE_CODE (op0) == SSA_NAME) - vr0 = *(get_value_range (op0)); - else if (is_gimple_min_invariant (op0)) - set_value_range_to_value (&vr0, op0, NULL); - else - set_value_range_to_varying (&vr0); - - op1 = gimple_assign_rhs3 (stmt); - if (TREE_CODE (op1) == SSA_NAME) - vr1 = *(get_value_range (op1)); - else if (is_gimple_min_invariant (op1)) - set_value_range_to_value (&vr1, op1, NULL); - else - set_value_range_to_varying (&vr1); - - /* The resulting value range is the union of the operand ranges */ - copy_value_range (vr, &vr0); - vrp_meet (vr, &vr1); -} - - -/* Extract range information from a comparison expression EXPR based - on the range of its operand and the expression code. */ - -static void -extract_range_from_comparison (value_range *vr, enum tree_code code, - tree type, tree op0, tree op1) -{ - bool sop; - tree val; - - val = vrp_evaluate_conditional_warnv_with_ops (code, op0, op1, false, &sop, - NULL); - if (val) - { - /* Since this expression was found on the RHS of an assignment, - its type may be different from _Bool. Convert VAL to EXPR's - type. */ - val = fold_convert (type, val); - if (is_gimple_min_invariant (val)) - set_value_range_to_value (vr, val, vr->equiv); - else - set_value_range (vr, VR_RANGE, val, val, vr->equiv); - } - else - /* The result of a comparison is always true or false. */ - set_value_range_to_truthvalue (vr, type); -} - -/* Helper function for simplify_internal_call_using_ranges and - extract_range_basic. Return true if OP0 SUBCODE OP1 for - SUBCODE {PLUS,MINUS,MULT}_EXPR is known to never overflow or - always overflow. Set *OVF to true if it is known to always - overflow. */ - -static bool -check_for_binary_op_overflow (enum tree_code subcode, tree type, - tree op0, tree op1, bool *ovf) -{ - value_range vr0 = VR_INITIALIZER; - value_range vr1 = VR_INITIALIZER; - if (TREE_CODE (op0) == SSA_NAME) - vr0 = *get_value_range (op0); - else if (TREE_CODE (op0) == INTEGER_CST) - set_value_range_to_value (&vr0, op0, NULL); - else - set_value_range_to_varying (&vr0); - - if (TREE_CODE (op1) == SSA_NAME) - vr1 = *get_value_range (op1); - else if (TREE_CODE (op1) == INTEGER_CST) - set_value_range_to_value (&vr1, op1, NULL); - else - set_value_range_to_varying (&vr1); - - if (!range_int_cst_p (&vr0) - || TREE_OVERFLOW (vr0.min) - || TREE_OVERFLOW (vr0.max)) - { - vr0.min = vrp_val_min (TREE_TYPE (op0)); - vr0.max = vrp_val_max (TREE_TYPE (op0)); - } - if (!range_int_cst_p (&vr1) - || TREE_OVERFLOW (vr1.min) - || TREE_OVERFLOW (vr1.max)) - { - vr1.min = vrp_val_min (TREE_TYPE (op1)); - vr1.max = vrp_val_max (TREE_TYPE (op1)); - } - *ovf = arith_overflowed_p (subcode, type, vr0.min, - subcode == MINUS_EXPR ? vr1.max : vr1.min); - if (arith_overflowed_p (subcode, type, vr0.max, - subcode == MINUS_EXPR ? vr1.min : vr1.max) != *ovf) - return false; - if (subcode == MULT_EXPR) - { - if (arith_overflowed_p (subcode, type, vr0.min, vr1.max) != *ovf - || arith_overflowed_p (subcode, type, vr0.max, vr1.min) != *ovf) - return false; - } - if (*ovf) - { - /* So far we found that there is an overflow on the boundaries. - That doesn't prove that there is an overflow even for all values - in between the boundaries. For that compute widest_int range - of the result and see if it doesn't overlap the range of - type. */ - widest_int wmin, wmax; - widest_int w[4]; - int i; - w[0] = wi::to_widest (vr0.min); - w[1] = wi::to_widest (vr0.max); - w[2] = wi::to_widest (vr1.min); - w[3] = wi::to_widest (vr1.max); - for (i = 0; i < 4; i++) - { - widest_int wt; - switch (subcode) - { - case PLUS_EXPR: - wt = wi::add (w[i & 1], w[2 + (i & 2) / 2]); - break; - case MINUS_EXPR: - wt = wi::sub (w[i & 1], w[2 + (i & 2) / 2]); - break; - case MULT_EXPR: - wt = wi::mul (w[i & 1], w[2 + (i & 2) / 2]); - break; - default: - gcc_unreachable (); - } - if (i == 0) - { - wmin = wt; - wmax = wt; - } - else - { - wmin = wi::smin (wmin, wt); - wmax = wi::smax (wmax, wt); - } - } - /* The result of op0 CODE op1 is known to be in range - [wmin, wmax]. */ - widest_int wtmin = wi::to_widest (vrp_val_min (type)); - widest_int wtmax = wi::to_widest (vrp_val_max (type)); - /* If all values in [wmin, wmax] are smaller than - [wtmin, wtmax] or all are larger than [wtmin, wtmax], - the arithmetic operation will always overflow. */ - if (wmax < wtmin || wmin > wtmax) - return true; - return false; - } - return true; -} - -/* Try to derive a nonnegative or nonzero range out of STMT relying - primarily on generic routines in fold in conjunction with range data. - Store the result in *VR */ - -static void -extract_range_basic (value_range *vr, gimple *stmt) -{ - bool sop; - tree type = gimple_expr_type (stmt); - - if (is_gimple_call (stmt)) - { - tree arg; - int mini, maxi, zerov = 0, prec; - enum tree_code subcode = ERROR_MARK; - combined_fn cfn = gimple_call_combined_fn (stmt); - scalar_int_mode mode; - - switch (cfn) - { - case CFN_BUILT_IN_CONSTANT_P: - /* If the call is __builtin_constant_p and the argument is a - function parameter resolve it to false. This avoids bogus - array bound warnings. - ??? We could do this as early as inlining is finished. */ - arg = gimple_call_arg (stmt, 0); - if (TREE_CODE (arg) == SSA_NAME - && SSA_NAME_IS_DEFAULT_DEF (arg) - && TREE_CODE (SSA_NAME_VAR (arg)) == PARM_DECL - && cfun->after_inlining) - { - set_value_range_to_null (vr, type); - return; - } - break; - /* Both __builtin_ffs* and __builtin_popcount return - [0, prec]. */ - CASE_CFN_FFS: - CASE_CFN_POPCOUNT: - arg = gimple_call_arg (stmt, 0); - prec = TYPE_PRECISION (TREE_TYPE (arg)); - mini = 0; - maxi = prec; - if (TREE_CODE (arg) == SSA_NAME) - { - value_range *vr0 = get_value_range (arg); - /* If arg is non-zero, then ffs or popcount - are non-zero. */ - if ((vr0->type == VR_RANGE - && range_includes_zero_p (vr0->min, vr0->max) == 0) - || (vr0->type == VR_ANTI_RANGE - && range_includes_zero_p (vr0->min, vr0->max) == 1)) - mini = 1; - /* If some high bits are known to be zero, - we can decrease the maximum. */ - if (vr0->type == VR_RANGE - && TREE_CODE (vr0->max) == INTEGER_CST - && !operand_less_p (vr0->min, - build_zero_cst (TREE_TYPE (vr0->min)))) - maxi = tree_floor_log2 (vr0->max) + 1; - } - goto bitop_builtin; - /* __builtin_parity* returns [0, 1]. */ - CASE_CFN_PARITY: - mini = 0; - maxi = 1; - goto bitop_builtin; - /* __builtin_c[lt]z* return [0, prec-1], except for - when the argument is 0, but that is undefined behavior. - On many targets where the CLZ RTL or optab value is defined - for 0 the value is prec, so include that in the range - by default. */ - CASE_CFN_CLZ: - arg = gimple_call_arg (stmt, 0); - prec = TYPE_PRECISION (TREE_TYPE (arg)); - mini = 0; - maxi = prec; - mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (arg)); - if (optab_handler (clz_optab, mode) != CODE_FOR_nothing - && CLZ_DEFINED_VALUE_AT_ZERO (mode, zerov) - /* Handle only the single common value. */ - && zerov != prec) - /* Magic value to give up, unless vr0 proves - arg is non-zero. */ - mini = -2; - if (TREE_CODE (arg) == SSA_NAME) - { - value_range *vr0 = get_value_range (arg); - /* From clz of VR_RANGE minimum we can compute - result maximum. */ - if (vr0->type == VR_RANGE - && TREE_CODE (vr0->min) == INTEGER_CST) - { - maxi = prec - 1 - tree_floor_log2 (vr0->min); - if (maxi != prec) - mini = 0; - } - else if (vr0->type == VR_ANTI_RANGE - && integer_zerop (vr0->min)) - { - maxi = prec - 1; - mini = 0; - } - if (mini == -2) - break; - /* From clz of VR_RANGE maximum we can compute - result minimum. */ - if (vr0->type == VR_RANGE - && TREE_CODE (vr0->max) == INTEGER_CST) - { - mini = prec - 1 - tree_floor_log2 (vr0->max); - if (mini == prec) - break; - } - } - if (mini == -2) - break; - goto bitop_builtin; - /* __builtin_ctz* return [0, prec-1], except for - when the argument is 0, but that is undefined behavior. - If there is a ctz optab for this mode and - CTZ_DEFINED_VALUE_AT_ZERO, include that in the range, - otherwise just assume 0 won't be seen. */ - CASE_CFN_CTZ: - arg = gimple_call_arg (stmt, 0); - prec = TYPE_PRECISION (TREE_TYPE (arg)); - mini = 0; - maxi = prec - 1; - mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (arg)); - if (optab_handler (ctz_optab, mode) != CODE_FOR_nothing - && CTZ_DEFINED_VALUE_AT_ZERO (mode, zerov)) - { - /* Handle only the two common values. */ - if (zerov == -1) - mini = -1; - else if (zerov == prec) - maxi = prec; - else - /* Magic value to give up, unless vr0 proves - arg is non-zero. */ - mini = -2; - } - if (TREE_CODE (arg) == SSA_NAME) - { - value_range *vr0 = get_value_range (arg); - /* If arg is non-zero, then use [0, prec - 1]. */ - if ((vr0->type == VR_RANGE - && integer_nonzerop (vr0->min)) - || (vr0->type == VR_ANTI_RANGE - && integer_zerop (vr0->min))) - { - mini = 0; - maxi = prec - 1; - } - /* If some high bits are known to be zero, - we can decrease the result maximum. */ - if (vr0->type == VR_RANGE - && TREE_CODE (vr0->max) == INTEGER_CST) - { - maxi = tree_floor_log2 (vr0->max); - /* For vr0 [0, 0] give up. */ - if (maxi == -1) - break; - } - } - if (mini == -2) - break; - goto bitop_builtin; - /* __builtin_clrsb* returns [0, prec-1]. */ - CASE_CFN_CLRSB: - arg = gimple_call_arg (stmt, 0); - prec = TYPE_PRECISION (TREE_TYPE (arg)); - mini = 0; - maxi = prec - 1; - goto bitop_builtin; - bitop_builtin: - set_value_range (vr, VR_RANGE, build_int_cst (type, mini), - build_int_cst (type, maxi), NULL); - return; - case CFN_UBSAN_CHECK_ADD: - subcode = PLUS_EXPR; - break; - case CFN_UBSAN_CHECK_SUB: - subcode = MINUS_EXPR; - break; - case CFN_UBSAN_CHECK_MUL: - subcode = MULT_EXPR; - break; - case CFN_GOACC_DIM_SIZE: - case CFN_GOACC_DIM_POS: - /* Optimizing these two internal functions helps the loop - optimizer eliminate outer comparisons. Size is [1,N] - and pos is [0,N-1]. */ - { - bool is_pos = cfn == CFN_GOACC_DIM_POS; - int axis = oacc_get_ifn_dim_arg (stmt); - int size = oacc_get_fn_dim_size (current_function_decl, axis); - - if (!size) - /* If it's dynamic, the backend might know a hardware - limitation. */ - size = targetm.goacc.dim_limit (axis); - - tree type = TREE_TYPE (gimple_call_lhs (stmt)); - set_value_range (vr, VR_RANGE, - build_int_cst (type, is_pos ? 0 : 1), - size ? build_int_cst (type, size - is_pos) - : vrp_val_max (type), NULL); - } - return; - case CFN_BUILT_IN_STRLEN: - if (tree lhs = gimple_call_lhs (stmt)) - if (ptrdiff_type_node - && (TYPE_PRECISION (ptrdiff_type_node) - == TYPE_PRECISION (TREE_TYPE (lhs)))) - { - tree type = TREE_TYPE (lhs); - tree max = vrp_val_max (ptrdiff_type_node); - wide_int wmax = wi::to_wide (max, TYPE_PRECISION (TREE_TYPE (max))); - tree range_min = build_zero_cst (type); - tree range_max = wide_int_to_tree (type, wmax - 1); - set_value_range (vr, VR_RANGE, range_min, range_max, NULL); - return; - } - break; - default: - break; - } - if (subcode != ERROR_MARK) - { - bool saved_flag_wrapv = flag_wrapv; - /* Pretend the arithmetics is wrapping. If there is - any overflow, we'll complain, but will actually do - wrapping operation. */ - flag_wrapv = 1; - extract_range_from_binary_expr (vr, subcode, type, - gimple_call_arg (stmt, 0), - gimple_call_arg (stmt, 1)); - flag_wrapv = saved_flag_wrapv; - - /* If for both arguments vrp_valueize returned non-NULL, - this should have been already folded and if not, it - wasn't folded because of overflow. Avoid removing the - UBSAN_CHECK_* calls in that case. */ - if (vr->type == VR_RANGE - && (vr->min == vr->max - || operand_equal_p (vr->min, vr->max, 0))) - set_value_range_to_varying (vr); - return; - } - } - /* Handle extraction of the two results (result of arithmetics and - a flag whether arithmetics overflowed) from {ADD,SUB,MUL}_OVERFLOW - internal function. Similarly from ATOMIC_COMPARE_EXCHANGE. */ - else if (is_gimple_assign (stmt) - && (gimple_assign_rhs_code (stmt) == REALPART_EXPR - || gimple_assign_rhs_code (stmt) == IMAGPART_EXPR) - && INTEGRAL_TYPE_P (type)) - { - enum tree_code code = gimple_assign_rhs_code (stmt); - tree op = gimple_assign_rhs1 (stmt); - if (TREE_CODE (op) == code && TREE_CODE (TREE_OPERAND (op, 0)) == SSA_NAME) - { - gimple *g = SSA_NAME_DEF_STMT (TREE_OPERAND (op, 0)); - if (is_gimple_call (g) && gimple_call_internal_p (g)) - { - enum tree_code subcode = ERROR_MARK; - switch (gimple_call_internal_fn (g)) - { - case IFN_ADD_OVERFLOW: - subcode = PLUS_EXPR; - break; - case IFN_SUB_OVERFLOW: - subcode = MINUS_EXPR; - break; - case IFN_MUL_OVERFLOW: - subcode = MULT_EXPR; - break; - case IFN_ATOMIC_COMPARE_EXCHANGE: - if (code == IMAGPART_EXPR) - { - /* This is the boolean return value whether compare and - exchange changed anything or not. */ - set_value_range (vr, VR_RANGE, build_int_cst (type, 0), - build_int_cst (type, 1), NULL); - return; - } - break; - default: - break; - } - if (subcode != ERROR_MARK) - { - tree op0 = gimple_call_arg (g, 0); - tree op1 = gimple_call_arg (g, 1); - if (code == IMAGPART_EXPR) - { - bool ovf = false; - if (check_for_binary_op_overflow (subcode, type, - op0, op1, &ovf)) - set_value_range_to_value (vr, - build_int_cst (type, ovf), - NULL); - else if (TYPE_PRECISION (type) == 1 - && !TYPE_UNSIGNED (type)) - set_value_range_to_varying (vr); - else - set_value_range (vr, VR_RANGE, build_int_cst (type, 0), - build_int_cst (type, 1), NULL); - } - else if (types_compatible_p (type, TREE_TYPE (op0)) - && types_compatible_p (type, TREE_TYPE (op1))) - { - bool saved_flag_wrapv = flag_wrapv; - /* Pretend the arithmetics is wrapping. If there is - any overflow, IMAGPART_EXPR will be set. */ - flag_wrapv = 1; - extract_range_from_binary_expr (vr, subcode, type, - op0, op1); - flag_wrapv = saved_flag_wrapv; - } - else - { - value_range vr0 = VR_INITIALIZER; - value_range vr1 = VR_INITIALIZER; - bool saved_flag_wrapv = flag_wrapv; - /* Pretend the arithmetics is wrapping. If there is - any overflow, IMAGPART_EXPR will be set. */ - flag_wrapv = 1; - extract_range_from_unary_expr (&vr0, NOP_EXPR, - type, op0); - extract_range_from_unary_expr (&vr1, NOP_EXPR, - type, op1); - extract_range_from_binary_expr_1 (vr, subcode, type, - &vr0, &vr1); - flag_wrapv = saved_flag_wrapv; - } - return; - } - } - } - } - if (INTEGRAL_TYPE_P (type) - && gimple_stmt_nonnegative_warnv_p (stmt, &sop)) - set_value_range_to_nonnegative (vr, type); - else if (vrp_stmt_computes_nonzero (stmt)) - set_value_range_to_nonnull (vr, type); - else - set_value_range_to_varying (vr); -} - - -/* Try to compute a useful range out of assignment STMT and store it - in *VR. */ - -static void -extract_range_from_assignment (value_range *vr, gassign *stmt) -{ - enum tree_code code = gimple_assign_rhs_code (stmt); - - if (code == ASSERT_EXPR) - extract_range_from_assert (vr, gimple_assign_rhs1 (stmt)); - else if (code == SSA_NAME) - extract_range_from_ssa_name (vr, gimple_assign_rhs1 (stmt)); - else if (TREE_CODE_CLASS (code) == tcc_binary) - extract_range_from_binary_expr (vr, gimple_assign_rhs_code (stmt), - gimple_expr_type (stmt), - gimple_assign_rhs1 (stmt), - gimple_assign_rhs2 (stmt)); - else if (TREE_CODE_CLASS (code) == tcc_unary) - extract_range_from_unary_expr (vr, gimple_assign_rhs_code (stmt), - gimple_expr_type (stmt), - gimple_assign_rhs1 (stmt)); - else if (code == COND_EXPR) - extract_range_from_cond_expr (vr, stmt); - else if (TREE_CODE_CLASS (code) == tcc_comparison) - extract_range_from_comparison (vr, gimple_assign_rhs_code (stmt), - gimple_expr_type (stmt), - gimple_assign_rhs1 (stmt), - gimple_assign_rhs2 (stmt)); - else if (get_gimple_rhs_class (code) == GIMPLE_SINGLE_RHS - && is_gimple_min_invariant (gimple_assign_rhs1 (stmt))) - set_value_range_to_value (vr, gimple_assign_rhs1 (stmt), NULL); - else - set_value_range_to_varying (vr); - - if (vr->type == VR_VARYING) - extract_range_basic (vr, stmt); -} - -/* Given a range VR, a LOOP and a variable VAR, determine whether it - would be profitable to adjust VR using scalar evolution information - for VAR. If so, update VR with the new limits. */ - -static void -adjust_range_with_scev (value_range *vr, struct loop *loop, - gimple *stmt, tree var) -{ - tree init, step, chrec, tmin, tmax, min, max, type, tem; - enum ev_direction dir; - - /* TODO. Don't adjust anti-ranges. An anti-range may provide - better opportunities than a regular range, but I'm not sure. */ - if (vr->type == VR_ANTI_RANGE) - return; - - chrec = instantiate_parameters (loop, analyze_scalar_evolution (loop, var)); - - /* Like in PR19590, scev can return a constant function. */ - if (is_gimple_min_invariant (chrec)) - { - set_value_range_to_value (vr, chrec, vr->equiv); - return; - } - - if (TREE_CODE (chrec) != POLYNOMIAL_CHREC) - return; - - init = initial_condition_in_loop_num (chrec, loop->num); - tem = op_with_constant_singleton_value_range (init); - if (tem) - init = tem; - step = evolution_part_in_loop_num (chrec, loop->num); - tem = op_with_constant_singleton_value_range (step); - if (tem) - step = tem; - - /* If STEP is symbolic, we can't know whether INIT will be the - minimum or maximum value in the range. Also, unless INIT is - a simple expression, compare_values and possibly other functions - in tree-vrp won't be able to handle it. */ - if (step == NULL_TREE - || !is_gimple_min_invariant (step) - || !valid_value_p (init)) - return; - - dir = scev_direction (chrec); - if (/* Do not adjust ranges if we do not know whether the iv increases - or decreases, ... */ - dir == EV_DIR_UNKNOWN - /* ... or if it may wrap. */ - || scev_probably_wraps_p (NULL_TREE, init, step, stmt, - get_chrec_loop (chrec), true)) - return; - - type = TREE_TYPE (var); - if (POINTER_TYPE_P (type) || !TYPE_MIN_VALUE (type)) - tmin = lower_bound_in_type (type, type); - else - tmin = TYPE_MIN_VALUE (type); - if (POINTER_TYPE_P (type) || !TYPE_MAX_VALUE (type)) - tmax = upper_bound_in_type (type, type); - else - tmax = TYPE_MAX_VALUE (type); - - /* Try to use estimated number of iterations for the loop to constrain the - final value in the evolution. */ - if (TREE_CODE (step) == INTEGER_CST - && is_gimple_val (init) - && (TREE_CODE (init) != SSA_NAME - || get_value_range (init)->type == VR_RANGE)) - { - widest_int nit; - - /* We are only entering here for loop header PHI nodes, so using - the number of latch executions is the correct thing to use. */ - if (max_loop_iterations (loop, &nit)) - { - value_range maxvr = VR_INITIALIZER; - signop sgn = TYPE_SIGN (TREE_TYPE (step)); - bool overflow; - - widest_int wtmp = wi::mul (wi::to_widest (step), nit, sgn, - &overflow); - /* If the multiplication overflowed we can't do a meaningful - adjustment. Likewise if the result doesn't fit in the type - of the induction variable. For a signed type we have to - check whether the result has the expected signedness which - is that of the step as number of iterations is unsigned. */ - if (!overflow - && wi::fits_to_tree_p (wtmp, TREE_TYPE (init)) - && (sgn == UNSIGNED - || wi::gts_p (wtmp, 0) == wi::gts_p (wi::to_wide (step), 0))) - { - tem = wide_int_to_tree (TREE_TYPE (init), wtmp); - extract_range_from_binary_expr (&maxvr, PLUS_EXPR, - TREE_TYPE (init), init, tem); - /* Likewise if the addition did. */ - if (maxvr.type == VR_RANGE) - { - value_range initvr = VR_INITIALIZER; - - if (TREE_CODE (init) == SSA_NAME) - initvr = *(get_value_range (init)); - else if (is_gimple_min_invariant (init)) - set_value_range_to_value (&initvr, init, NULL); - else - return; - - /* Check if init + nit * step overflows. Though we checked - scev {init, step}_loop doesn't wrap, it is not enough - because the loop may exit immediately. Overflow could - happen in the plus expression in this case. */ - if ((dir == EV_DIR_DECREASES - && compare_values (maxvr.min, initvr.min) != -1) - || (dir == EV_DIR_GROWS - && compare_values (maxvr.max, initvr.max) != 1)) - return; - - tmin = maxvr.min; - tmax = maxvr.max; - } - } - } - } - - if (vr->type == VR_VARYING || vr->type == VR_UNDEFINED) - { - min = tmin; - max = tmax; - - /* For VARYING or UNDEFINED ranges, just about anything we get - from scalar evolutions should be better. */ - - if (dir == EV_DIR_DECREASES) - max = init; - else - min = init; - } - else if (vr->type == VR_RANGE) - { - min = vr->min; - max = vr->max; - - if (dir == EV_DIR_DECREASES) - { - /* INIT is the maximum value. If INIT is lower than VR->MAX - but no smaller than VR->MIN, set VR->MAX to INIT. */ - if (compare_values (init, max) == -1) - max = init; - - /* According to the loop information, the variable does not - overflow. */ - if (compare_values (min, tmin) == -1) - min = tmin; - - } - else - { - /* If INIT is bigger than VR->MIN, set VR->MIN to INIT. */ - if (compare_values (init, min) == 1) - min = init; - - if (compare_values (tmax, max) == -1) - max = tmax; - } - } - else - return; - - /* If we just created an invalid range with the minimum - greater than the maximum, we fail conservatively. - This should happen only in unreachable - parts of code, or for invalid programs. */ - if (compare_values (min, max) == 1) - return; - - /* Even for valid range info, sometimes overflow flag will leak in. - As GIMPLE IL should have no constants with TREE_OVERFLOW set, we - drop them. */ - if (TREE_OVERFLOW_P (min)) - min = drop_tree_overflow (min); - if (TREE_OVERFLOW_P (max)) - max = drop_tree_overflow (max); - - set_value_range (vr, VR_RANGE, min, max, vr->equiv); -} - - -/* Given two numeric value ranges VR0, VR1 and a comparison code COMP: - - - Return BOOLEAN_TRUE_NODE if VR0 COMP VR1 always returns true for - all the values in the ranges. - - - Return BOOLEAN_FALSE_NODE if the comparison always returns false. - - - Return NULL_TREE if it is not always possible to determine the - value of the comparison. - - Also set *STRICT_OVERFLOW_P to indicate whether comparision evaluation - assumed signed overflow is undefined. */ - - -static tree -compare_ranges (enum tree_code comp, value_range *vr0, value_range *vr1, - bool *strict_overflow_p) -{ - /* VARYING or UNDEFINED ranges cannot be compared. */ - if (vr0->type == VR_VARYING - || vr0->type == VR_UNDEFINED - || vr1->type == VR_VARYING - || vr1->type == VR_UNDEFINED) - return NULL_TREE; - - /* Anti-ranges need to be handled separately. */ - if (vr0->type == VR_ANTI_RANGE || vr1->type == VR_ANTI_RANGE) - { - /* If both are anti-ranges, then we cannot compute any - comparison. */ - if (vr0->type == VR_ANTI_RANGE && vr1->type == VR_ANTI_RANGE) - return NULL_TREE; - - /* These comparisons are never statically computable. */ - if (comp == GT_EXPR - || comp == GE_EXPR - || comp == LT_EXPR - || comp == LE_EXPR) - return NULL_TREE; - - /* Equality can be computed only between a range and an - anti-range. ~[VAL1, VAL2] == [VAL1, VAL2] is always false. */ - if (vr0->type == VR_RANGE) - { - /* To simplify processing, make VR0 the anti-range. */ - value_range *tmp = vr0; - vr0 = vr1; - vr1 = tmp; - } - - gcc_assert (comp == NE_EXPR || comp == EQ_EXPR); - - if (compare_values_warnv (vr0->min, vr1->min, strict_overflow_p) == 0 - && compare_values_warnv (vr0->max, vr1->max, strict_overflow_p) == 0) - return (comp == NE_EXPR) ? boolean_true_node : boolean_false_node; - - return NULL_TREE; - } - - /* Simplify processing. If COMP is GT_EXPR or GE_EXPR, switch the - operands around and change the comparison code. */ - if (comp == GT_EXPR || comp == GE_EXPR) - { - comp = (comp == GT_EXPR) ? LT_EXPR : LE_EXPR; - std::swap (vr0, vr1); - } - - if (comp == EQ_EXPR) - { - /* Equality may only be computed if both ranges represent - exactly one value. */ - if (compare_values_warnv (vr0->min, vr0->max, strict_overflow_p) == 0 - && compare_values_warnv (vr1->min, vr1->max, strict_overflow_p) == 0) - { - int cmp_min = compare_values_warnv (vr0->min, vr1->min, - strict_overflow_p); - int cmp_max = compare_values_warnv (vr0->max, vr1->max, - strict_overflow_p); - if (cmp_min == 0 && cmp_max == 0) - return boolean_true_node; - else if (cmp_min != -2 && cmp_max != -2) - return boolean_false_node; - } - /* If [V0_MIN, V1_MAX] < [V1_MIN, V1_MAX] then V0 != V1. */ - else if (compare_values_warnv (vr0->min, vr1->max, - strict_overflow_p) == 1 - || compare_values_warnv (vr1->min, vr0->max, - strict_overflow_p) == 1) - return boolean_false_node; - - return NULL_TREE; - } - else if (comp == NE_EXPR) - { - int cmp1, cmp2; - - /* If VR0 is completely to the left or completely to the right - of VR1, they are always different. Notice that we need to - make sure that both comparisons yield similar results to - avoid comparing values that cannot be compared at - compile-time. */ - cmp1 = compare_values_warnv (vr0->max, vr1->min, strict_overflow_p); - cmp2 = compare_values_warnv (vr0->min, vr1->max, strict_overflow_p); - if ((cmp1 == -1 && cmp2 == -1) || (cmp1 == 1 && cmp2 == 1)) - return boolean_true_node; - - /* If VR0 and VR1 represent a single value and are identical, - return false. */ - else if (compare_values_warnv (vr0->min, vr0->max, - strict_overflow_p) == 0 - && compare_values_warnv (vr1->min, vr1->max, - strict_overflow_p) == 0 - && compare_values_warnv (vr0->min, vr1->min, - strict_overflow_p) == 0 - && compare_values_warnv (vr0->max, vr1->max, - strict_overflow_p) == 0) - return boolean_false_node; - - /* Otherwise, they may or may not be different. */ - else - return NULL_TREE; - } - else if (comp == LT_EXPR || comp == LE_EXPR) - { - int tst; - - /* If VR0 is to the left of VR1, return true. */ - tst = compare_values_warnv (vr0->max, vr1->min, strict_overflow_p); - if ((comp == LT_EXPR && tst == -1) - || (comp == LE_EXPR && (tst == -1 || tst == 0))) - return boolean_true_node; - - /* If VR0 is to the right of VR1, return false. */ - tst = compare_values_warnv (vr0->min, vr1->max, strict_overflow_p); - if ((comp == LT_EXPR && (tst == 0 || tst == 1)) - || (comp == LE_EXPR && tst == 1)) - return boolean_false_node; - - /* Otherwise, we don't know. */ - return NULL_TREE; - } - - gcc_unreachable (); -} - - -/* Given a value range VR, a value VAL and a comparison code COMP, return - BOOLEAN_TRUE_NODE if VR COMP VAL always returns true for all the - values in VR. Return BOOLEAN_FALSE_NODE if the comparison - always returns false. Return NULL_TREE if it is not always - possible to determine the value of the comparison. Also set - *STRICT_OVERFLOW_P to indicate whether comparision evaluation - assumed signed overflow is undefined. */ - -static tree -compare_range_with_value (enum tree_code comp, value_range *vr, tree val, - bool *strict_overflow_p) -{ - if (vr->type == VR_VARYING || vr->type == VR_UNDEFINED) - return NULL_TREE; - - /* Anti-ranges need to be handled separately. */ - if (vr->type == VR_ANTI_RANGE) - { - /* For anti-ranges, the only predicates that we can compute at - compile time are equality and inequality. */ - if (comp == GT_EXPR - || comp == GE_EXPR - || comp == LT_EXPR - || comp == LE_EXPR) - return NULL_TREE; - - /* ~[VAL_1, VAL_2] OP VAL is known if VAL_1 <= VAL <= VAL_2. */ - if (value_inside_range (val, vr->min, vr->max) == 1) - return (comp == NE_EXPR) ? boolean_true_node : boolean_false_node; - - return NULL_TREE; - } - - if (comp == EQ_EXPR) - { - /* EQ_EXPR may only be computed if VR represents exactly - one value. */ - if (compare_values_warnv (vr->min, vr->max, strict_overflow_p) == 0) - { - int cmp = compare_values_warnv (vr->min, val, strict_overflow_p); - if (cmp == 0) - return boolean_true_node; - else if (cmp == -1 || cmp == 1 || cmp == 2) - return boolean_false_node; - } - else if (compare_values_warnv (val, vr->min, strict_overflow_p) == -1 - || compare_values_warnv (vr->max, val, strict_overflow_p) == -1) - return boolean_false_node; - - return NULL_TREE; - } - else if (comp == NE_EXPR) - { - /* If VAL is not inside VR, then they are always different. */ - if (compare_values_warnv (vr->max, val, strict_overflow_p) == -1 - || compare_values_warnv (vr->min, val, strict_overflow_p) == 1) - return boolean_true_node; - - /* If VR represents exactly one value equal to VAL, then return - false. */ - if (compare_values_warnv (vr->min, vr->max, strict_overflow_p) == 0 - && compare_values_warnv (vr->min, val, strict_overflow_p) == 0) - return boolean_false_node; - - /* Otherwise, they may or may not be different. */ - return NULL_TREE; - } - else if (comp == LT_EXPR || comp == LE_EXPR) - { - int tst; - - /* If VR is to the left of VAL, return true. */ - tst = compare_values_warnv (vr->max, val, strict_overflow_p); - if ((comp == LT_EXPR && tst == -1) - || (comp == LE_EXPR && (tst == -1 || tst == 0))) - return boolean_true_node; - - /* If VR is to the right of VAL, return false. */ - tst = compare_values_warnv (vr->min, val, strict_overflow_p); - if ((comp == LT_EXPR && (tst == 0 || tst == 1)) - || (comp == LE_EXPR && tst == 1)) - return boolean_false_node; - - /* Otherwise, we don't know. */ - return NULL_TREE; - } - else if (comp == GT_EXPR || comp == GE_EXPR) - { - int tst; - - /* If VR is to the right of VAL, return true. */ - tst = compare_values_warnv (vr->min, val, strict_overflow_p); - if ((comp == GT_EXPR && tst == 1) - || (comp == GE_EXPR && (tst == 0 || tst == 1))) - return boolean_true_node; - - /* If VR is to the left of VAL, return false. */ - tst = compare_values_warnv (vr->max, val, strict_overflow_p); - if ((comp == GT_EXPR && (tst == -1 || tst == 0)) - || (comp == GE_EXPR && tst == -1)) - return boolean_false_node; - - /* Otherwise, we don't know. */ - return NULL_TREE; - } - - gcc_unreachable (); -} - - /* Debugging dumps. */ void dump_value_range (FILE *, const value_range *); void debug_value_range (value_range *); void dump_all_value_ranges (FILE *); -void debug_all_value_ranges (void); void dump_vr_equiv (FILE *, bitmap); void debug_vr_equiv (bitmap); @@ -4487,37 +2618,6 @@ debug_value_range (value_range *vr) } -/* Dump value ranges of all SSA_NAMEs to FILE. */ - -void -dump_all_value_ranges (FILE *file) -{ - size_t i; - - for (i = 0; i < num_vr_values; i++) - { - if (vr_value[i]) - { - print_generic_expr (file, ssa_name (i)); - fprintf (file, ": "); - dump_value_range (file, vr_value[i]); - fprintf (file, "\n"); - } - } - - fprintf (file, "\n"); -} - - -/* Dump all value ranges to stderr. */ - -DEBUG_FUNCTION void -debug_all_value_ranges (void) -{ - dump_all_value_ranges (stderr); -} - - /* Given a COND_EXPR COND of the form 'V OP W', and an SSA name V, create a new SSA name N and return the assertion assignment 'N = ASSERT_EXPR <V, V OP W>'. */ @@ -4565,7 +2665,7 @@ fp_predicate (gimple *stmt) describes the inferred range. Return true if a range could be inferred. */ -static bool +bool infer_value_range (gimple *stmt, tree op, tree_code *comp_code_p, tree *val_p) { *val_p = NULL_TREE; @@ -5000,7 +3100,7 @@ overflow_comparison_p_1 (enum tree_code code, tree op0, tree op1, {ADD,SUB}_OVERFLOW sequences later in the optimizer pipeline. But the alternate range representation is often useful within VRP. */ -static bool +bool overflow_comparison_p (tree_code code, tree name, tree val, bool use_equiv_p, tree *new_cst) { @@ -5737,7 +3837,7 @@ is_masked_range_test (tree name, tree valt, enum tree_code cond_code, the condition COND contributing to the conditional jump pointed to by SI. */ -static void +void register_edge_assert_for (tree name, edge e, enum tree_code cond_code, tree cond_op0, tree cond_op1, vec<assert_info> &asserts) @@ -6649,6 +4749,34 @@ insert_range_assertions (void) BITMAP_FREE (need_assert_for); } +class vrp_prop : public ssa_propagation_engine +{ + public: + enum ssa_prop_result visit_stmt (gimple *, edge *, tree *) FINAL OVERRIDE; + enum ssa_prop_result visit_phi (gphi *) FINAL OVERRIDE; + + void vrp_initialize (void); + void vrp_finalize (bool); + void check_all_array_refs (void); + void check_array_ref (location_t, tree, bool); + void search_for_addr_array (tree, location_t); + + class vr_values vr_values; + /* Temporary delegator to minimize code churn. */ + value_range *get_value_range (const_tree op) + { return vr_values.get_value_range (op); } + void set_defs_to_varying (gimple *stmt) + { return vr_values.set_defs_to_varying (stmt); } + void extract_range_from_stmt (gimple *stmt, edge *taken_edge_p, + tree *output_p, value_range *vr) + { vr_values.extract_range_from_stmt (stmt, taken_edge_p, output_p, vr); } + bool update_value_range (const_tree op, value_range *vr) + { return vr_values.update_value_range (op, vr); } + void extract_range_basic (value_range *vr, gimple *stmt) + { vr_values.extract_range_basic (vr, stmt); } + void extract_range_from_phi_node (gphi *phi, value_range *vr) + { vr_values.extract_range_from_phi_node (phi, vr); } +}; /* Checks one ARRAY_REF in REF, located at LOCUS. Ignores flexible arrays and "struct" hacks. If VRP can determine that the array subscript is a constant, check if it is outside valid @@ -6656,8 +4784,9 @@ insert_range_assertions (void) non-overlapping with valid range. IGNORE_OFF_BY_ONE is true if the ARRAY_REF is inside a ADDR_EXPR. */ -static void -check_array_ref (location_t location, tree ref, bool ignore_off_by_one) +void +vrp_prop::check_array_ref (location_t location, tree ref, + bool ignore_off_by_one) { value_range *vr = NULL; tree low_sub, up_sub; @@ -6749,8 +4878,8 @@ check_array_ref (location_t location, tree ref, bool ignore_off_by_one) /* Searches if the expr T, located at LOCATION computes address of an ARRAY_REF, and call check_array_ref on it. */ -static void -search_for_addr_array (tree t, location_t location) +void +vrp_prop::search_for_addr_array (tree t, location_t location) { /* Check each ARRAY_REFs in the reference chain. */ do @@ -6837,12 +4966,13 @@ check_array_bounds (tree *tp, int *walk_subtree, void *data) *walk_subtree = TRUE; + vrp_prop *vrp_prop = (class vrp_prop *)wi->info; if (TREE_CODE (t) == ARRAY_REF) - check_array_ref (location, t, false /*ignore_off_by_one*/); + vrp_prop->check_array_ref (location, t, false /*ignore_off_by_one*/); else if (TREE_CODE (t) == ADDR_EXPR) { - search_for_addr_array (t, location); + vrp_prop->search_for_addr_array (t, location); *walk_subtree = FALSE; } @@ -6852,8 +4982,8 @@ check_array_bounds (tree *tp, int *walk_subtree, void *data) /* Walk over all statements of all reachable BBs and call check_array_bounds on them. */ -static void -check_all_array_refs (void) +void +vrp_prop::check_all_array_refs () { basic_block bb; gimple_stmt_iterator si; @@ -6880,6 +5010,8 @@ check_all_array_refs (void) memset (&wi, 0, sizeof (wi)); + wi.info = this; + walk_gimple_op (gsi_stmt (si), check_array_bounds, &wi); @@ -7079,10 +5211,9 @@ remove_range_assertions (void) } } - /* Return true if STMT is interesting for VRP. */ -static bool +bool stmt_interesting_for_vrp (gimple *stmt) { if (gimple_code (stmt) == GIMPLE_PHI) @@ -7128,22 +5259,10 @@ stmt_interesting_for_vrp (gimple *stmt) return false; } -/* Initialize VRP lattice. */ - -static void -vrp_initialize_lattice () -{ - values_propagated = false; - num_vr_values = num_ssa_names; - vr_value = XCNEWVEC (value_range *, num_vr_values); - vr_phi_edge_counts = XCNEWVEC (int, num_ssa_names); - bitmap_obstack_initialize (&vrp_equiv_obstack); -} - /* Initialization required by ssa_propagate engine. */ -static void -vrp_initialize () +void +vrp_prop::vrp_initialize () { basic_block bb; @@ -7184,595 +5303,6 @@ vrp_initialize () } } -/* Return the singleton value-range for NAME or NAME. */ - -static inline tree -vrp_valueize (tree name) -{ - if (TREE_CODE (name) == SSA_NAME) - { - value_range *vr = get_value_range (name); - if (vr->type == VR_RANGE - && (TREE_CODE (vr->min) == SSA_NAME - || is_gimple_min_invariant (vr->min)) - && vrp_operand_equal_p (vr->min, vr->max)) - return vr->min; - } - return name; -} - -/* Return the singleton value-range for NAME if that is a constant - but signal to not follow SSA edges. */ - -static inline tree -vrp_valueize_1 (tree name) -{ - if (TREE_CODE (name) == SSA_NAME) - { - /* If the definition may be simulated again we cannot follow - this SSA edge as the SSA propagator does not necessarily - re-visit the use. */ - gimple *def_stmt = SSA_NAME_DEF_STMT (name); - if (!gimple_nop_p (def_stmt) - && prop_simulate_again_p (def_stmt)) - return NULL_TREE; - value_range *vr = get_value_range (name); - if (range_int_cst_singleton_p (vr)) - return vr->min; - } - return name; -} - -/* Visit assignment STMT. If it produces an interesting range, record - the range in VR and set LHS to OUTPUT_P. */ - -static void -vrp_visit_assignment_or_call (gimple *stmt, tree *output_p, value_range *vr) -{ - tree lhs; - enum gimple_code code = gimple_code (stmt); - lhs = gimple_get_lhs (stmt); - *output_p = NULL_TREE; - - /* We only keep track of ranges in integral and pointer types. */ - if (TREE_CODE (lhs) == SSA_NAME - && ((INTEGRAL_TYPE_P (TREE_TYPE (lhs)) - /* It is valid to have NULL MIN/MAX values on a type. See - build_range_type. */ - && TYPE_MIN_VALUE (TREE_TYPE (lhs)) - && TYPE_MAX_VALUE (TREE_TYPE (lhs))) - || POINTER_TYPE_P (TREE_TYPE (lhs)))) - { - *output_p = lhs; - - /* Try folding the statement to a constant first. */ - tree tem = gimple_fold_stmt_to_constant_1 (stmt, vrp_valueize, - vrp_valueize_1); - if (tem) - { - if (TREE_CODE (tem) == SSA_NAME - && (SSA_NAME_IS_DEFAULT_DEF (tem) - || ! prop_simulate_again_p (SSA_NAME_DEF_STMT (tem)))) - { - extract_range_from_ssa_name (vr, tem); - return; - } - else if (is_gimple_min_invariant (tem)) - { - set_value_range_to_value (vr, tem, NULL); - return; - } - } - /* Then dispatch to value-range extracting functions. */ - if (code == GIMPLE_CALL) - extract_range_basic (vr, stmt); - else - extract_range_from_assignment (vr, as_a <gassign *> (stmt)); - } -} - -/* Helper that gets the value range of the SSA_NAME with version I - or a symbolic range containing the SSA_NAME only if the value range - is varying or undefined. */ - -static inline value_range -get_vr_for_comparison (int i) -{ - value_range vr = *get_value_range (ssa_name (i)); - - /* If name N_i does not have a valid range, use N_i as its own - range. This allows us to compare against names that may - have N_i in their ranges. */ - if (vr.type == VR_VARYING || vr.type == VR_UNDEFINED) - { - vr.type = VR_RANGE; - vr.min = ssa_name (i); - vr.max = ssa_name (i); - } - - return vr; -} - -/* Compare all the value ranges for names equivalent to VAR with VAL - using comparison code COMP. Return the same value returned by - compare_range_with_value, including the setting of - *STRICT_OVERFLOW_P. */ - -static tree -compare_name_with_value (enum tree_code comp, tree var, tree val, - bool *strict_overflow_p, bool use_equiv_p) -{ - bitmap_iterator bi; - unsigned i; - bitmap e; - tree retval, t; - int used_strict_overflow; - bool sop; - value_range equiv_vr; - - /* Get the set of equivalences for VAR. */ - e = get_value_range (var)->equiv; - - /* Start at -1. Set it to 0 if we do a comparison without relying - on overflow, or 1 if all comparisons rely on overflow. */ - used_strict_overflow = -1; - - /* Compare vars' value range with val. */ - equiv_vr = get_vr_for_comparison (SSA_NAME_VERSION (var)); - sop = false; - retval = compare_range_with_value (comp, &equiv_vr, val, &sop); - if (retval) - used_strict_overflow = sop ? 1 : 0; - - /* If the equiv set is empty we have done all work we need to do. */ - if (e == NULL) - { - if (retval - && used_strict_overflow > 0) - *strict_overflow_p = true; - return retval; - } - - EXECUTE_IF_SET_IN_BITMAP (e, 0, i, bi) - { - tree name = ssa_name (i); - if (! name) - continue; - - if (! use_equiv_p - && ! SSA_NAME_IS_DEFAULT_DEF (name) - && prop_simulate_again_p (SSA_NAME_DEF_STMT (name))) - continue; - - equiv_vr = get_vr_for_comparison (i); - sop = false; - t = compare_range_with_value (comp, &equiv_vr, val, &sop); - if (t) - { - /* If we get different answers from different members - of the equivalence set this check must be in a dead - code region. Folding it to a trap representation - would be correct here. For now just return don't-know. */ - if (retval != NULL - && t != retval) - { - retval = NULL_TREE; - break; - } - retval = t; - - if (!sop) - used_strict_overflow = 0; - else if (used_strict_overflow < 0) - used_strict_overflow = 1; - } - } - - if (retval - && used_strict_overflow > 0) - *strict_overflow_p = true; - - return retval; -} - - -/* Given a comparison code COMP and names N1 and N2, compare all the - ranges equivalent to N1 against all the ranges equivalent to N2 - to determine the value of N1 COMP N2. Return the same value - returned by compare_ranges. Set *STRICT_OVERFLOW_P to indicate - whether we relied on undefined signed overflow in the comparison. */ - - -static tree -compare_names (enum tree_code comp, tree n1, tree n2, - bool *strict_overflow_p) -{ - tree t, retval; - bitmap e1, e2; - bitmap_iterator bi1, bi2; - unsigned i1, i2; - int used_strict_overflow; - static bitmap_obstack *s_obstack = NULL; - static bitmap s_e1 = NULL, s_e2 = NULL; - - /* Compare the ranges of every name equivalent to N1 against the - ranges of every name equivalent to N2. */ - e1 = get_value_range (n1)->equiv; - e2 = get_value_range (n2)->equiv; - - /* Use the fake bitmaps if e1 or e2 are not available. */ - if (s_obstack == NULL) - { - s_obstack = XNEW (bitmap_obstack); - bitmap_obstack_initialize (s_obstack); - s_e1 = BITMAP_ALLOC (s_obstack); - s_e2 = BITMAP_ALLOC (s_obstack); - } - if (e1 == NULL) - e1 = s_e1; - if (e2 == NULL) - e2 = s_e2; - - /* Add N1 and N2 to their own set of equivalences to avoid - duplicating the body of the loop just to check N1 and N2 - ranges. */ - bitmap_set_bit (e1, SSA_NAME_VERSION (n1)); - bitmap_set_bit (e2, SSA_NAME_VERSION (n2)); - - /* If the equivalence sets have a common intersection, then the two - names can be compared without checking their ranges. */ - if (bitmap_intersect_p (e1, e2)) - { - bitmap_clear_bit (e1, SSA_NAME_VERSION (n1)); - bitmap_clear_bit (e2, SSA_NAME_VERSION (n2)); - - return (comp == EQ_EXPR || comp == GE_EXPR || comp == LE_EXPR) - ? boolean_true_node - : boolean_false_node; - } - - /* Start at -1. Set it to 0 if we do a comparison without relying - on overflow, or 1 if all comparisons rely on overflow. */ - used_strict_overflow = -1; - - /* Otherwise, compare all the equivalent ranges. First, add N1 and - N2 to their own set of equivalences to avoid duplicating the body - of the loop just to check N1 and N2 ranges. */ - EXECUTE_IF_SET_IN_BITMAP (e1, 0, i1, bi1) - { - if (! ssa_name (i1)) - continue; - - value_range vr1 = get_vr_for_comparison (i1); - - t = retval = NULL_TREE; - EXECUTE_IF_SET_IN_BITMAP (e2, 0, i2, bi2) - { - if (! ssa_name (i2)) - continue; - - bool sop = false; - - value_range vr2 = get_vr_for_comparison (i2); - - t = compare_ranges (comp, &vr1, &vr2, &sop); - if (t) - { - /* If we get different answers from different members - of the equivalence set this check must be in a dead - code region. Folding it to a trap representation - would be correct here. For now just return don't-know. */ - if (retval != NULL - && t != retval) - { - bitmap_clear_bit (e1, SSA_NAME_VERSION (n1)); - bitmap_clear_bit (e2, SSA_NAME_VERSION (n2)); - return NULL_TREE; - } - retval = t; - - if (!sop) - used_strict_overflow = 0; - else if (used_strict_overflow < 0) - used_strict_overflow = 1; - } - } - - if (retval) - { - bitmap_clear_bit (e1, SSA_NAME_VERSION (n1)); - bitmap_clear_bit (e2, SSA_NAME_VERSION (n2)); - if (used_strict_overflow > 0) - *strict_overflow_p = true; - return retval; - } - } - - /* None of the equivalent ranges are useful in computing this - comparison. */ - bitmap_clear_bit (e1, SSA_NAME_VERSION (n1)); - bitmap_clear_bit (e2, SSA_NAME_VERSION (n2)); - return NULL_TREE; -} - -/* Helper function for vrp_evaluate_conditional_warnv & other - optimizers. */ - -static tree -vrp_evaluate_conditional_warnv_with_ops_using_ranges (enum tree_code code, - tree op0, tree op1, - bool * strict_overflow_p) -{ - value_range *vr0, *vr1; - - vr0 = (TREE_CODE (op0) == SSA_NAME) ? get_value_range (op0) : NULL; - vr1 = (TREE_CODE (op1) == SSA_NAME) ? get_value_range (op1) : NULL; - - tree res = NULL_TREE; - if (vr0 && vr1) - res = compare_ranges (code, vr0, vr1, strict_overflow_p); - if (!res && vr0) - res = compare_range_with_value (code, vr0, op1, strict_overflow_p); - if (!res && vr1) - res = (compare_range_with_value - (swap_tree_comparison (code), vr1, op0, strict_overflow_p)); - return res; -} - -/* Helper function for vrp_evaluate_conditional_warnv. */ - -static tree -vrp_evaluate_conditional_warnv_with_ops (enum tree_code code, tree op0, - tree op1, bool use_equiv_p, - bool *strict_overflow_p, bool *only_ranges) -{ - tree ret; - if (only_ranges) - *only_ranges = true; - - /* We only deal with integral and pointer types. */ - if (!INTEGRAL_TYPE_P (TREE_TYPE (op0)) - && !POINTER_TYPE_P (TREE_TYPE (op0))) - return NULL_TREE; - - /* If OP0 CODE OP1 is an overflow comparison, if it can be expressed - as a simple equality test, then prefer that over its current form - for evaluation. - - An overflow test which collapses to an equality test can always be - expressed as a comparison of one argument against zero. Overflow - occurs when the chosen argument is zero and does not occur if the - chosen argument is not zero. */ - tree x; - if (overflow_comparison_p (code, op0, op1, use_equiv_p, &x)) - { - wide_int max = wi::max_value (TYPE_PRECISION (TREE_TYPE (op0)), UNSIGNED); - /* B = A - 1; if (A < B) -> B = A - 1; if (A == 0) - B = A - 1; if (A > B) -> B = A - 1; if (A != 0) - B = A + 1; if (B < A) -> B = A + 1; if (B == 0) - B = A + 1; if (B > A) -> B = A + 1; if (B != 0) */ - if (integer_zerop (x)) - { - op1 = x; - code = (code == LT_EXPR || code == LE_EXPR) ? EQ_EXPR : NE_EXPR; - } - /* B = A + 1; if (A > B) -> B = A + 1; if (B == 0) - B = A + 1; if (A < B) -> B = A + 1; if (B != 0) - B = A - 1; if (B > A) -> B = A - 1; if (A == 0) - B = A - 1; if (B < A) -> B = A - 1; if (A != 0) */ - else if (wi::to_wide (x) == max - 1) - { - op0 = op1; - op1 = wide_int_to_tree (TREE_TYPE (op0), 0); - code = (code == GT_EXPR || code == GE_EXPR) ? EQ_EXPR : NE_EXPR; - } - } - - if ((ret = vrp_evaluate_conditional_warnv_with_ops_using_ranges - (code, op0, op1, strict_overflow_p))) - return ret; - if (only_ranges) - *only_ranges = false; - /* Do not use compare_names during propagation, it's quadratic. */ - if (TREE_CODE (op0) == SSA_NAME && TREE_CODE (op1) == SSA_NAME - && use_equiv_p) - return compare_names (code, op0, op1, strict_overflow_p); - else if (TREE_CODE (op0) == SSA_NAME) - return compare_name_with_value (code, op0, op1, - strict_overflow_p, use_equiv_p); - else if (TREE_CODE (op1) == SSA_NAME) - return compare_name_with_value (swap_tree_comparison (code), op1, op0, - strict_overflow_p, use_equiv_p); - return NULL_TREE; -} - -/* Given (CODE OP0 OP1) within STMT, try to simplify it based on value range - information. Return NULL if the conditional can not be evaluated. - The ranges of all the names equivalent with the operands in COND - will be used when trying to compute the value. If the result is - based on undefined signed overflow, issue a warning if - appropriate. */ - -static tree -vrp_evaluate_conditional (tree_code code, tree op0, tree op1, gimple *stmt) -{ - bool sop; - tree ret; - bool only_ranges; - - /* Some passes and foldings leak constants with overflow flag set - into the IL. Avoid doing wrong things with these and bail out. */ - if ((TREE_CODE (op0) == INTEGER_CST - && TREE_OVERFLOW (op0)) - || (TREE_CODE (op1) == INTEGER_CST - && TREE_OVERFLOW (op1))) - return NULL_TREE; - - sop = false; - ret = vrp_evaluate_conditional_warnv_with_ops (code, op0, op1, true, &sop, - &only_ranges); - - if (ret && sop) - { - enum warn_strict_overflow_code wc; - const char* warnmsg; - - if (is_gimple_min_invariant (ret)) - { - wc = WARN_STRICT_OVERFLOW_CONDITIONAL; - warnmsg = G_("assuming signed overflow does not occur when " - "simplifying conditional to constant"); - } - else - { - wc = WARN_STRICT_OVERFLOW_COMPARISON; - warnmsg = G_("assuming signed overflow does not occur when " - "simplifying conditional"); - } - - if (issue_strict_overflow_warning (wc)) - { - location_t location; - - if (!gimple_has_location (stmt)) - location = input_location; - else - location = gimple_location (stmt); - warning_at (location, OPT_Wstrict_overflow, "%s", warnmsg); - } - } - - if (warn_type_limits - && ret && only_ranges - && TREE_CODE_CLASS (code) == tcc_comparison - && TREE_CODE (op0) == SSA_NAME) - { - /* If the comparison is being folded and the operand on the LHS - is being compared against a constant value that is outside of - the natural range of OP0's type, then the predicate will - always fold regardless of the value of OP0. If -Wtype-limits - was specified, emit a warning. */ - tree type = TREE_TYPE (op0); - value_range *vr0 = get_value_range (op0); - - if (vr0->type == VR_RANGE - && INTEGRAL_TYPE_P (type) - && vrp_val_is_min (vr0->min) - && vrp_val_is_max (vr0->max) - && is_gimple_min_invariant (op1)) - { - location_t location; - - if (!gimple_has_location (stmt)) - location = input_location; - else - location = gimple_location (stmt); - - warning_at (location, OPT_Wtype_limits, - integer_zerop (ret) - ? G_("comparison always false " - "due to limited range of data type") - : G_("comparison always true " - "due to limited range of data type")); - } - } - - return ret; -} - - -/* Visit conditional statement STMT. If we can determine which edge - will be taken out of STMT's basic block, record it in - *TAKEN_EDGE_P. Otherwise, set *TAKEN_EDGE_P to NULL. */ - -static void -vrp_visit_cond_stmt (gcond *stmt, edge *taken_edge_p) -{ - tree val; - - *taken_edge_p = NULL; - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - tree use; - ssa_op_iter i; - - fprintf (dump_file, "\nVisiting conditional with predicate: "); - print_gimple_stmt (dump_file, stmt, 0); - fprintf (dump_file, "\nWith known ranges\n"); - - FOR_EACH_SSA_TREE_OPERAND (use, stmt, i, SSA_OP_USE) - { - fprintf (dump_file, "\t"); - print_generic_expr (dump_file, use); - fprintf (dump_file, ": "); - dump_value_range (dump_file, vr_value[SSA_NAME_VERSION (use)]); - } - - fprintf (dump_file, "\n"); - } - - /* Compute the value of the predicate COND by checking the known - ranges of each of its operands. - - Note that we cannot evaluate all the equivalent ranges here - because those ranges may not yet be final and with the current - propagation strategy, we cannot determine when the value ranges - of the names in the equivalence set have changed. - - For instance, given the following code fragment - - i_5 = PHI <8, i_13> - ... - i_14 = ASSERT_EXPR <i_5, i_5 != 0> - if (i_14 == 1) - ... - - Assume that on the first visit to i_14, i_5 has the temporary - range [8, 8] because the second argument to the PHI function is - not yet executable. We derive the range ~[0, 0] for i_14 and the - equivalence set { i_5 }. So, when we visit 'if (i_14 == 1)' for - the first time, since i_14 is equivalent to the range [8, 8], we - determine that the predicate is always false. - - On the next round of propagation, i_13 is determined to be - VARYING, which causes i_5 to drop down to VARYING. So, another - visit to i_14 is scheduled. In this second visit, we compute the - exact same range and equivalence set for i_14, namely ~[0, 0] and - { i_5 }. But we did not have the previous range for i_5 - registered, so vrp_visit_assignment thinks that the range for - i_14 has not changed. Therefore, the predicate 'if (i_14 == 1)' - is not visited again, which stops propagation from visiting - statements in the THEN clause of that if(). - - To properly fix this we would need to keep the previous range - value for the names in the equivalence set. This way we would've - discovered that from one visit to the other i_5 changed from - range [8, 8] to VR_VARYING. - - However, fixing this apparent limitation may not be worth the - additional checking. Testing on several code bases (GCC, DLV, - MICO, TRAMP3D and SPEC2000) showed that doing this results in - 4 more predicates folded in SPEC. */ - - bool sop; - val = vrp_evaluate_conditional_warnv_with_ops (gimple_cond_code (stmt), - gimple_cond_lhs (stmt), - gimple_cond_rhs (stmt), - false, &sop, NULL); - if (val) - *taken_edge_p = find_taken_edge (gimple_bb (stmt), val); - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nPredicate evaluates to: "); - if (val == NULL_TREE) - fprintf (dump_file, "DON'T KNOW\n"); - else - print_generic_stmt (dump_file, val); - } -} - /* Searches the case label vector VEC for the index *IDX of the CASE_LABEL that includes the value VAL. The search is restricted to the range [START_IDX, n - 1] where n is the size of VEC. @@ -7786,7 +5316,7 @@ vrp_visit_cond_stmt (gcond *stmt, edge *taken_edge_p) If VAL is larger than any CASE_LABEL, n is placed on IDX and false is returned. */ -static bool +bool find_case_label_index (gswitch *stmt, size_t start_idx, tree val, size_t *idx) { size_t n = gimple_switch_num_labels (stmt); @@ -7836,7 +5366,7 @@ find_case_label_index (gswitch *stmt, size_t start_idx, tree val, size_t *idx) then MAX_IDX < MIN_IDX. Returns true if the default label is not needed. */ -static bool +bool find_case_label_range (gswitch *stmt, tree min, tree max, size_t *min_idx, size_t *max_idx) { @@ -7887,208 +5417,6 @@ find_case_label_range (gswitch *stmt, tree min, tree max, size_t *min_idx, } } -/* Searches the case label vector VEC for the ranges of CASE_LABELs that are - used in range VR. The indices are placed in MIN_IDX1, MAX_IDX, MIN_IDX2 and - MAX_IDX2. If the ranges of CASE_LABELs are empty then MAX_IDX1 < MIN_IDX1. - Returns true if the default label is not needed. */ - -static bool -find_case_label_ranges (gswitch *stmt, value_range *vr, size_t *min_idx1, - size_t *max_idx1, size_t *min_idx2, - size_t *max_idx2) -{ - size_t i, j, k, l; - unsigned int n = gimple_switch_num_labels (stmt); - bool take_default; - tree case_low, case_high; - tree min = vr->min, max = vr->max; - - gcc_checking_assert (vr->type == VR_RANGE || vr->type == VR_ANTI_RANGE); - - take_default = !find_case_label_range (stmt, min, max, &i, &j); - - /* Set second range to emtpy. */ - *min_idx2 = 1; - *max_idx2 = 0; - - if (vr->type == VR_RANGE) - { - *min_idx1 = i; - *max_idx1 = j; - return !take_default; - } - - /* Set first range to all case labels. */ - *min_idx1 = 1; - *max_idx1 = n - 1; - - if (i > j) - return false; - - /* Make sure all the values of case labels [i , j] are contained in - range [MIN, MAX]. */ - case_low = CASE_LOW (gimple_switch_label (stmt, i)); - case_high = CASE_HIGH (gimple_switch_label (stmt, j)); - if (tree_int_cst_compare (case_low, min) < 0) - i += 1; - if (case_high != NULL_TREE - && tree_int_cst_compare (max, case_high) < 0) - j -= 1; - - if (i > j) - return false; - - /* If the range spans case labels [i, j], the corresponding anti-range spans - the labels [1, i - 1] and [j + 1, n - 1]. */ - k = j + 1; - l = n - 1; - if (k > l) - { - k = 1; - l = 0; - } - - j = i - 1; - i = 1; - if (i > j) - { - i = k; - j = l; - k = 1; - l = 0; - } - - *min_idx1 = i; - *max_idx1 = j; - *min_idx2 = k; - *max_idx2 = l; - return false; -} - -/* Visit switch statement STMT. If we can determine which edge - will be taken out of STMT's basic block, record it in - *TAKEN_EDGE_P. Otherwise, *TAKEN_EDGE_P set to NULL. */ - -static void -vrp_visit_switch_stmt (gswitch *stmt, edge *taken_edge_p) -{ - tree op, val; - value_range *vr; - size_t i = 0, j = 0, k, l; - bool take_default; - - *taken_edge_p = NULL; - op = gimple_switch_index (stmt); - if (TREE_CODE (op) != SSA_NAME) - return; - - vr = get_value_range (op); - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nVisiting switch expression with operand "); - print_generic_expr (dump_file, op); - fprintf (dump_file, " with known range "); - dump_value_range (dump_file, vr); - fprintf (dump_file, "\n"); - } - - if ((vr->type != VR_RANGE - && vr->type != VR_ANTI_RANGE) - || symbolic_range_p (vr)) - return; - - /* Find the single edge that is taken from the switch expression. */ - take_default = !find_case_label_ranges (stmt, vr, &i, &j, &k, &l); - - /* Check if the range spans no CASE_LABEL. If so, we only reach the default - label */ - if (j < i) - { - gcc_assert (take_default); - val = gimple_switch_default_label (stmt); - } - else - { - /* Check if labels with index i to j and maybe the default label - are all reaching the same label. */ - - val = gimple_switch_label (stmt, i); - if (take_default - && CASE_LABEL (gimple_switch_default_label (stmt)) - != CASE_LABEL (val)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, " not a single destination for this " - "range\n"); - return; - } - for (++i; i <= j; ++i) - { - if (CASE_LABEL (gimple_switch_label (stmt, i)) != CASE_LABEL (val)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, " not a single destination for this " - "range\n"); - return; - } - } - for (; k <= l; ++k) - { - if (CASE_LABEL (gimple_switch_label (stmt, k)) != CASE_LABEL (val)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, " not a single destination for this " - "range\n"); - return; - } - } - } - - *taken_edge_p = find_edge (gimple_bb (stmt), - label_to_block (CASE_LABEL (val))); - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, " will take edge to "); - print_generic_stmt (dump_file, CASE_LABEL (val)); - } -} - - -/* Evaluate statement STMT. If the statement produces a useful range, - set VR and corepsponding OUTPUT_P. - - If STMT is a conditional branch and we can determine its truth - value, the taken edge is recorded in *TAKEN_EDGE_P. */ - -static void -extract_range_from_stmt (gimple *stmt, edge *taken_edge_p, - tree *output_p, value_range *vr) -{ - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nVisiting statement:\n"); - print_gimple_stmt (dump_file, stmt, 0, dump_flags); - } - - if (!stmt_interesting_for_vrp (stmt)) - gcc_assert (stmt_ends_bb_p (stmt)); - else if (is_gimple_assign (stmt) || is_gimple_call (stmt)) - vrp_visit_assignment_or_call (stmt, output_p, vr); - else if (gimple_code (stmt) == GIMPLE_COND) - vrp_visit_cond_stmt (as_a <gcond *> (stmt), taken_edge_p); - else if (gimple_code (stmt) == GIMPLE_SWITCH) - vrp_visit_switch_stmt (as_a <gswitch *> (stmt), taken_edge_p); -} - -class vrp_prop : public ssa_propagation_engine -{ - public: - enum ssa_prop_result visit_stmt (gimple *, edge *, tree *) FINAL OVERRIDE; - enum ssa_prop_result visit_phi (gphi *) FINAL OVERRIDE; -}; - /* Evaluate statement STMT. If the statement produces a useful range, return SSA_PROP_INTERESTING and record the SSA name with the interesting range into *OUTPUT_P. @@ -8847,7 +6175,9 @@ vrp_intersect_ranges_1 (value_range *vr0, value_range *vr1) bitmap_ior_into (vr0->equiv, vr1->equiv); else if (vr1->equiv && !vr0->equiv) { - vr0->equiv = BITMAP_ALLOC (&vrp_equiv_obstack); + /* All equivalence bitmaps are allocated from the same obstack. So + we can use the obstack associated with VR to allocate vr0->equiv. */ + vr0->equiv = BITMAP_ALLOC (vr1->equiv->obstack); bitmap_copy (vr0->equiv, vr1->equiv); } } @@ -8972,222 +6302,6 @@ vrp_meet (value_range *vr0, const value_range *vr1) /* Visit all arguments for PHI node PHI that flow through executable edges. If a valid value range can be derived from all the incoming - value ranges, set a new range in VR_RESULT. */ - -static void -extract_range_from_phi_node (gphi *phi, value_range *vr_result) -{ - size_t i; - tree lhs = PHI_RESULT (phi); - value_range *lhs_vr = get_value_range (lhs); - bool first = true; - int edges, old_edges; - struct loop *l; - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\nVisiting PHI node: "); - print_gimple_stmt (dump_file, phi, 0, dump_flags); - } - - bool may_simulate_backedge_again = false; - edges = 0; - for (i = 0; i < gimple_phi_num_args (phi); i++) - { - edge e = gimple_phi_arg_edge (phi, i); - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, - " Argument #%d (%d -> %d %sexecutable)\n", - (int) i, e->src->index, e->dest->index, - (e->flags & EDGE_EXECUTABLE) ? "" : "not "); - } - - if (e->flags & EDGE_EXECUTABLE) - { - tree arg = PHI_ARG_DEF (phi, i); - value_range vr_arg; - - ++edges; - - if (TREE_CODE (arg) == SSA_NAME) - { - /* See if we are eventually going to change one of the args. */ - gimple *def_stmt = SSA_NAME_DEF_STMT (arg); - if (! gimple_nop_p (def_stmt) - && prop_simulate_again_p (def_stmt) - && e->flags & EDGE_DFS_BACK) - may_simulate_backedge_again = true; - - vr_arg = *(get_value_range (arg)); - /* Do not allow equivalences or symbolic ranges to leak in from - backedges. That creates invalid equivalencies. - See PR53465 and PR54767. */ - if (e->flags & EDGE_DFS_BACK) - { - if (vr_arg.type == VR_RANGE - || vr_arg.type == VR_ANTI_RANGE) - { - vr_arg.equiv = NULL; - if (symbolic_range_p (&vr_arg)) - { - vr_arg.type = VR_VARYING; - vr_arg.min = NULL_TREE; - vr_arg.max = NULL_TREE; - } - } - } - else - { - /* If the non-backedge arguments range is VR_VARYING then - we can still try recording a simple equivalence. */ - if (vr_arg.type == VR_VARYING) - { - vr_arg.type = VR_RANGE; - vr_arg.min = arg; - vr_arg.max = arg; - vr_arg.equiv = NULL; - } - } - } - else - { - if (TREE_OVERFLOW_P (arg)) - arg = drop_tree_overflow (arg); - - vr_arg.type = VR_RANGE; - vr_arg.min = arg; - vr_arg.max = arg; - vr_arg.equiv = NULL; - } - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "\t"); - print_generic_expr (dump_file, arg, dump_flags); - fprintf (dump_file, ": "); - dump_value_range (dump_file, &vr_arg); - fprintf (dump_file, "\n"); - } - - if (first) - copy_value_range (vr_result, &vr_arg); - else - vrp_meet (vr_result, &vr_arg); - first = false; - - if (vr_result->type == VR_VARYING) - break; - } - } - - if (vr_result->type == VR_VARYING) - goto varying; - else if (vr_result->type == VR_UNDEFINED) - goto update_range; - - old_edges = vr_phi_edge_counts[SSA_NAME_VERSION (lhs)]; - vr_phi_edge_counts[SSA_NAME_VERSION (lhs)] = edges; - - /* To prevent infinite iterations in the algorithm, derive ranges - when the new value is slightly bigger or smaller than the - previous one. We don't do this if we have seen a new executable - edge; this helps us avoid an infinity for conditionals - which are not in a loop. If the old value-range was VR_UNDEFINED - use the updated range and iterate one more time. If we will not - simulate this PHI again via the backedge allow us to iterate. */ - if (edges > 0 - && gimple_phi_num_args (phi) > 1 - && edges == old_edges - && lhs_vr->type != VR_UNDEFINED - && may_simulate_backedge_again) - { - /* Compare old and new ranges, fall back to varying if the - values are not comparable. */ - int cmp_min = compare_values (lhs_vr->min, vr_result->min); - if (cmp_min == -2) - goto varying; - int cmp_max = compare_values (lhs_vr->max, vr_result->max); - if (cmp_max == -2) - goto varying; - - /* For non VR_RANGE or for pointers fall back to varying if - the range changed. */ - if ((lhs_vr->type != VR_RANGE || vr_result->type != VR_RANGE - || POINTER_TYPE_P (TREE_TYPE (lhs))) - && (cmp_min != 0 || cmp_max != 0)) - goto varying; - - /* If the new minimum is larger than the previous one - retain the old value. If the new minimum value is smaller - than the previous one and not -INF go all the way to -INF + 1. - In the first case, to avoid infinite bouncing between different - minimums, and in the other case to avoid iterating millions of - times to reach -INF. Going to -INF + 1 also lets the following - iteration compute whether there will be any overflow, at the - expense of one additional iteration. */ - if (cmp_min < 0) - vr_result->min = lhs_vr->min; - else if (cmp_min > 0 - && !vrp_val_is_min (vr_result->min)) - vr_result->min - = int_const_binop (PLUS_EXPR, - vrp_val_min (TREE_TYPE (vr_result->min)), - build_int_cst (TREE_TYPE (vr_result->min), 1)); - - /* Similarly for the maximum value. */ - if (cmp_max > 0) - vr_result->max = lhs_vr->max; - else if (cmp_max < 0 - && !vrp_val_is_max (vr_result->max)) - vr_result->max - = int_const_binop (MINUS_EXPR, - vrp_val_max (TREE_TYPE (vr_result->min)), - build_int_cst (TREE_TYPE (vr_result->min), 1)); - - /* If we dropped either bound to +-INF then if this is a loop - PHI node SCEV may known more about its value-range. */ - if (cmp_min > 0 || cmp_min < 0 - || cmp_max < 0 || cmp_max > 0) - goto scev_check; - - goto infinite_check; - } - - goto update_range; - -varying: - set_value_range_to_varying (vr_result); - -scev_check: - /* If this is a loop PHI node SCEV may known more about its value-range. - scev_check can be reached from two paths, one is a fall through from above - "varying" label, the other is direct goto from code block which tries to - avoid infinite simulation. */ - if ((l = loop_containing_stmt (phi)) - && l->header == gimple_bb (phi)) - adjust_range_with_scev (vr_result, l, phi, lhs); - -infinite_check: - /* If we will end up with a (-INF, +INF) range, set it to - VARYING. Same if the previous max value was invalid for - the type and we end up with vr_result.min > vr_result.max. */ - if ((vr_result->type == VR_RANGE || vr_result->type == VR_ANTI_RANGE) - && !((vrp_val_is_max (vr_result->max) && vrp_val_is_min (vr_result->min)) - || compare_values (vr_result->min, vr_result->max) > 0)) - ; - else - set_value_range_to_varying (vr_result); - - /* If the new range is different than the previous value, keep - iterating. */ -update_range: - return; -} - -/* Visit all arguments for PHI node PHI that flow through executable - edges. If a valid value range can be derived from all the incoming value ranges, set a new range for the LHS of PHI. */ enum ssa_prop_result @@ -9217,1259 +6331,31 @@ vrp_prop::visit_phi (gphi *phi) return SSA_PROP_NOT_INTERESTING; } -/* Simplify boolean operations if the source is known - to be already a boolean. */ -static bool -simplify_truth_ops_using_ranges (gimple_stmt_iterator *gsi, gimple *stmt) -{ - enum tree_code rhs_code = gimple_assign_rhs_code (stmt); - tree lhs, op0, op1; - bool need_conversion; - - /* We handle only !=/== case here. */ - gcc_assert (rhs_code == EQ_EXPR || rhs_code == NE_EXPR); - - op0 = gimple_assign_rhs1 (stmt); - if (!op_with_boolean_value_range_p (op0)) - return false; - - op1 = gimple_assign_rhs2 (stmt); - if (!op_with_boolean_value_range_p (op1)) - return false; - - /* Reduce number of cases to handle to NE_EXPR. As there is no - BIT_XNOR_EXPR we cannot replace A == B with a single statement. */ - if (rhs_code == EQ_EXPR) - { - if (TREE_CODE (op1) == INTEGER_CST) - op1 = int_const_binop (BIT_XOR_EXPR, op1, - build_int_cst (TREE_TYPE (op1), 1)); - else - return false; - } - - lhs = gimple_assign_lhs (stmt); - need_conversion - = !useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (op0)); - - /* Make sure to not sign-extend a 1-bit 1 when converting the result. */ - if (need_conversion - && !TYPE_UNSIGNED (TREE_TYPE (op0)) - && TYPE_PRECISION (TREE_TYPE (op0)) == 1 - && TYPE_PRECISION (TREE_TYPE (lhs)) > 1) - return false; - - /* For A != 0 we can substitute A itself. */ - if (integer_zerop (op1)) - gimple_assign_set_rhs_with_ops (gsi, - need_conversion - ? NOP_EXPR : TREE_CODE (op0), op0); - /* For A != B we substitute A ^ B. Either with conversion. */ - else if (need_conversion) - { - tree tem = make_ssa_name (TREE_TYPE (op0)); - gassign *newop - = gimple_build_assign (tem, BIT_XOR_EXPR, op0, op1); - gsi_insert_before (gsi, newop, GSI_SAME_STMT); - if (INTEGRAL_TYPE_P (TREE_TYPE (tem)) - && TYPE_PRECISION (TREE_TYPE (tem)) > 1) - set_range_info (tem, VR_RANGE, - wi::zero (TYPE_PRECISION (TREE_TYPE (tem))), - wi::one (TYPE_PRECISION (TREE_TYPE (tem)))); - gimple_assign_set_rhs_with_ops (gsi, NOP_EXPR, tem); - } - /* Or without. */ - else - gimple_assign_set_rhs_with_ops (gsi, BIT_XOR_EXPR, op0, op1); - update_stmt (gsi_stmt (*gsi)); - fold_stmt (gsi, follow_single_use_edges); - - return true; -} - -/* Simplify a division or modulo operator to a right shift or bitwise and - if the first operand is unsigned or is greater than zero and the second - operand is an exact power of two. For TRUNC_MOD_EXPR op0 % op1 with - constant op1 (op1min = op1) or with op1 in [op1min, op1max] range, - optimize it into just op0 if op0's range is known to be a subset of - [-op1min + 1, op1min - 1] for signed and [0, op1min - 1] for unsigned - modulo. */ - -static bool -simplify_div_or_mod_using_ranges (gimple_stmt_iterator *gsi, gimple *stmt) -{ - enum tree_code rhs_code = gimple_assign_rhs_code (stmt); - tree val = NULL; - tree op0 = gimple_assign_rhs1 (stmt); - tree op1 = gimple_assign_rhs2 (stmt); - tree op0min = NULL_TREE, op0max = NULL_TREE; - tree op1min = op1; - value_range *vr = NULL; - - if (TREE_CODE (op0) == INTEGER_CST) - { - op0min = op0; - op0max = op0; - } - else - { - vr = get_value_range (op0); - if (range_int_cst_p (vr)) - { - op0min = vr->min; - op0max = vr->max; - } - } - - if (rhs_code == TRUNC_MOD_EXPR - && TREE_CODE (op1) == SSA_NAME) - { - value_range *vr1 = get_value_range (op1); - if (range_int_cst_p (vr1)) - op1min = vr1->min; - } - if (rhs_code == TRUNC_MOD_EXPR - && TREE_CODE (op1min) == INTEGER_CST - && tree_int_cst_sgn (op1min) == 1 - && op0max - && tree_int_cst_lt (op0max, op1min)) - { - if (TYPE_UNSIGNED (TREE_TYPE (op0)) - || tree_int_cst_sgn (op0min) >= 0 - || tree_int_cst_lt (fold_unary (NEGATE_EXPR, TREE_TYPE (op1min), op1min), - op0min)) - { - /* If op0 already has the range op0 % op1 has, - then TRUNC_MOD_EXPR won't change anything. */ - gimple_assign_set_rhs_from_tree (gsi, op0); - return true; - } - } - - if (TREE_CODE (op0) != SSA_NAME) - return false; - - if (!integer_pow2p (op1)) - { - /* X % -Y can be only optimized into X % Y either if - X is not INT_MIN, or Y is not -1. Fold it now, as after - remove_range_assertions the range info might be not available - anymore. */ - if (rhs_code == TRUNC_MOD_EXPR - && fold_stmt (gsi, follow_single_use_edges)) - return true; - return false; - } - - if (TYPE_UNSIGNED (TREE_TYPE (op0))) - val = integer_one_node; - else - { - bool sop = false; - - val = compare_range_with_value (GE_EXPR, vr, integer_zero_node, &sop); - - if (val - && sop - && integer_onep (val) - && issue_strict_overflow_warning (WARN_STRICT_OVERFLOW_MISC)) - { - location_t location; - - if (!gimple_has_location (stmt)) - location = input_location; - else - location = gimple_location (stmt); - warning_at (location, OPT_Wstrict_overflow, - "assuming signed overflow does not occur when " - "simplifying %</%> or %<%%%> to %<>>%> or %<&%>"); - } - } - - if (val && integer_onep (val)) - { - tree t; - - if (rhs_code == TRUNC_DIV_EXPR) - { - t = build_int_cst (integer_type_node, tree_log2 (op1)); - gimple_assign_set_rhs_code (stmt, RSHIFT_EXPR); - gimple_assign_set_rhs1 (stmt, op0); - gimple_assign_set_rhs2 (stmt, t); - } - else - { - t = build_int_cst (TREE_TYPE (op1), 1); - t = int_const_binop (MINUS_EXPR, op1, t); - t = fold_convert (TREE_TYPE (op0), t); - - gimple_assign_set_rhs_code (stmt, BIT_AND_EXPR); - gimple_assign_set_rhs1 (stmt, op0); - gimple_assign_set_rhs2 (stmt, t); - } - - update_stmt (stmt); - fold_stmt (gsi, follow_single_use_edges); - return true; - } - - return false; -} - -/* Simplify a min or max if the ranges of the two operands are - disjoint. Return true if we do simplify. */ - -static bool -simplify_min_or_max_using_ranges (gimple_stmt_iterator *gsi, gimple *stmt) -{ - tree op0 = gimple_assign_rhs1 (stmt); - tree op1 = gimple_assign_rhs2 (stmt); - bool sop = false; - tree val; - - val = (vrp_evaluate_conditional_warnv_with_ops_using_ranges - (LE_EXPR, op0, op1, &sop)); - if (!val) - { - sop = false; - val = (vrp_evaluate_conditional_warnv_with_ops_using_ranges - (LT_EXPR, op0, op1, &sop)); - } - - if (val) - { - if (sop && issue_strict_overflow_warning (WARN_STRICT_OVERFLOW_MISC)) - { - location_t location; - - if (!gimple_has_location (stmt)) - location = input_location; - else - location = gimple_location (stmt); - warning_at (location, OPT_Wstrict_overflow, - "assuming signed overflow does not occur when " - "simplifying %<min/max (X,Y)%> to %<X%> or %<Y%>"); - } - - /* VAL == TRUE -> OP0 < or <= op1 - VAL == FALSE -> OP0 > or >= op1. */ - tree res = ((gimple_assign_rhs_code (stmt) == MAX_EXPR) - == integer_zerop (val)) ? op0 : op1; - gimple_assign_set_rhs_from_tree (gsi, res); - return true; - } - - return false; -} - -/* If the operand to an ABS_EXPR is >= 0, then eliminate the - ABS_EXPR. If the operand is <= 0, then simplify the - ABS_EXPR into a NEGATE_EXPR. */ - -static bool -simplify_abs_using_ranges (gimple_stmt_iterator *gsi, gimple *stmt) -{ - tree op = gimple_assign_rhs1 (stmt); - value_range *vr = get_value_range (op); - - if (vr) - { - tree val = NULL; - bool sop = false; - - val = compare_range_with_value (LE_EXPR, vr, integer_zero_node, &sop); - if (!val) - { - /* The range is neither <= 0 nor > 0. Now see if it is - either < 0 or >= 0. */ - sop = false; - val = compare_range_with_value (LT_EXPR, vr, integer_zero_node, - &sop); - } - - if (val) - { - if (sop && issue_strict_overflow_warning (WARN_STRICT_OVERFLOW_MISC)) - { - location_t location; - - if (!gimple_has_location (stmt)) - location = input_location; - else - location = gimple_location (stmt); - warning_at (location, OPT_Wstrict_overflow, - "assuming signed overflow does not occur when " - "simplifying %<abs (X)%> to %<X%> or %<-X%>"); - } - - gimple_assign_set_rhs1 (stmt, op); - if (integer_zerop (val)) - gimple_assign_set_rhs_code (stmt, SSA_NAME); - else - gimple_assign_set_rhs_code (stmt, NEGATE_EXPR); - update_stmt (stmt); - fold_stmt (gsi, follow_single_use_edges); - return true; - } - } - - return false; -} - -/* Optimize away redundant BIT_AND_EXPR and BIT_IOR_EXPR. - If all the bits that are being cleared by & are already - known to be zero from VR, or all the bits that are being - set by | are already known to be one from VR, the bit - operation is redundant. */ - -static bool -simplify_bit_ops_using_ranges (gimple_stmt_iterator *gsi, gimple *stmt) -{ - tree op0 = gimple_assign_rhs1 (stmt); - tree op1 = gimple_assign_rhs2 (stmt); - tree op = NULL_TREE; - value_range vr0 = VR_INITIALIZER; - value_range vr1 = VR_INITIALIZER; - wide_int may_be_nonzero0, may_be_nonzero1; - wide_int must_be_nonzero0, must_be_nonzero1; - wide_int mask; - - if (TREE_CODE (op0) == SSA_NAME) - vr0 = *(get_value_range (op0)); - else if (is_gimple_min_invariant (op0)) - set_value_range_to_value (&vr0, op0, NULL); - else - return false; - - if (TREE_CODE (op1) == SSA_NAME) - vr1 = *(get_value_range (op1)); - else if (is_gimple_min_invariant (op1)) - set_value_range_to_value (&vr1, op1, NULL); - else - return false; - - if (!zero_nonzero_bits_from_vr (TREE_TYPE (op0), &vr0, &may_be_nonzero0, - &must_be_nonzero0)) - return false; - if (!zero_nonzero_bits_from_vr (TREE_TYPE (op1), &vr1, &may_be_nonzero1, - &must_be_nonzero1)) - return false; - - switch (gimple_assign_rhs_code (stmt)) - { - case BIT_AND_EXPR: - mask = wi::bit_and_not (may_be_nonzero0, must_be_nonzero1); - if (mask == 0) - { - op = op0; - break; - } - mask = wi::bit_and_not (may_be_nonzero1, must_be_nonzero0); - if (mask == 0) - { - op = op1; - break; - } - break; - case BIT_IOR_EXPR: - mask = wi::bit_and_not (may_be_nonzero0, must_be_nonzero1); - if (mask == 0) - { - op = op1; - break; - } - mask = wi::bit_and_not (may_be_nonzero1, must_be_nonzero0); - if (mask == 0) - { - op = op0; - break; - } - break; - default: - gcc_unreachable (); - } - - if (op == NULL_TREE) - return false; - - gimple_assign_set_rhs_with_ops (gsi, TREE_CODE (op), op); - update_stmt (gsi_stmt (*gsi)); - return true; -} - -/* We are comparing trees OP0 and OP1 using COND_CODE. OP0 has - a known value range VR. - - If there is one and only one value which will satisfy the - conditional, then return that value. Else return NULL. - - If signed overflow must be undefined for the value to satisfy - the conditional, then set *STRICT_OVERFLOW_P to true. */ - -static tree -test_for_singularity (enum tree_code cond_code, tree op0, - tree op1, value_range *vr) -{ - tree min = NULL; - tree max = NULL; - - /* Extract minimum/maximum values which satisfy the conditional as it was - written. */ - if (cond_code == LE_EXPR || cond_code == LT_EXPR) - { - min = TYPE_MIN_VALUE (TREE_TYPE (op0)); - - max = op1; - if (cond_code == LT_EXPR) - { - tree one = build_int_cst (TREE_TYPE (op0), 1); - max = fold_build2 (MINUS_EXPR, TREE_TYPE (op0), max, one); - /* Signal to compare_values_warnv this expr doesn't overflow. */ - if (EXPR_P (max)) - TREE_NO_WARNING (max) = 1; - } - } - else if (cond_code == GE_EXPR || cond_code == GT_EXPR) - { - max = TYPE_MAX_VALUE (TREE_TYPE (op0)); - - min = op1; - if (cond_code == GT_EXPR) - { - tree one = build_int_cst (TREE_TYPE (op0), 1); - min = fold_build2 (PLUS_EXPR, TREE_TYPE (op0), min, one); - /* Signal to compare_values_warnv this expr doesn't overflow. */ - if (EXPR_P (min)) - TREE_NO_WARNING (min) = 1; - } - } - - /* Now refine the minimum and maximum values using any - value range information we have for op0. */ - if (min && max) - { - if (compare_values (vr->min, min) == 1) - min = vr->min; - if (compare_values (vr->max, max) == -1) - max = vr->max; - - /* If the new min/max values have converged to a single value, - then there is only one value which can satisfy the condition, - return that value. */ - if (operand_equal_p (min, max, 0) && is_gimple_min_invariant (min)) - return min; - } - return NULL; -} - -/* Return whether the value range *VR fits in an integer type specified - by PRECISION and UNSIGNED_P. */ - -static bool -range_fits_type_p (value_range *vr, unsigned dest_precision, signop dest_sgn) -{ - tree src_type; - unsigned src_precision; - widest_int tem; - signop src_sgn; - - /* We can only handle integral and pointer types. */ - src_type = TREE_TYPE (vr->min); - if (!INTEGRAL_TYPE_P (src_type) - && !POINTER_TYPE_P (src_type)) - return false; - - /* An extension is fine unless VR is SIGNED and dest_sgn is UNSIGNED, - and so is an identity transform. */ - src_precision = TYPE_PRECISION (TREE_TYPE (vr->min)); - src_sgn = TYPE_SIGN (src_type); - if ((src_precision < dest_precision - && !(dest_sgn == UNSIGNED && src_sgn == SIGNED)) - || (src_precision == dest_precision && src_sgn == dest_sgn)) - return true; - - /* Now we can only handle ranges with constant bounds. */ - if (vr->type != VR_RANGE - || TREE_CODE (vr->min) != INTEGER_CST - || TREE_CODE (vr->max) != INTEGER_CST) - return false; - - /* For sign changes, the MSB of the wide_int has to be clear. - An unsigned value with its MSB set cannot be represented by - a signed wide_int, while a negative value cannot be represented - by an unsigned wide_int. */ - if (src_sgn != dest_sgn - && (wi::lts_p (wi::to_wide (vr->min), 0) - || wi::lts_p (wi::to_wide (vr->max), 0))) - return false; - - /* Then we can perform the conversion on both ends and compare - the result for equality. */ - tem = wi::ext (wi::to_widest (vr->min), dest_precision, dest_sgn); - if (tem != wi::to_widest (vr->min)) - return false; - tem = wi::ext (wi::to_widest (vr->max), dest_precision, dest_sgn); - if (tem != wi::to_widest (vr->max)) - return false; - - return true; -} - -/* Simplify a conditional using a relational operator to an equality - test if the range information indicates only one value can satisfy - the original conditional. */ - -static bool -simplify_cond_using_ranges_1 (gcond *stmt) -{ - tree op0 = gimple_cond_lhs (stmt); - tree op1 = gimple_cond_rhs (stmt); - enum tree_code cond_code = gimple_cond_code (stmt); - - if (cond_code != NE_EXPR - && cond_code != EQ_EXPR - && TREE_CODE (op0) == SSA_NAME - && INTEGRAL_TYPE_P (TREE_TYPE (op0)) - && is_gimple_min_invariant (op1)) - { - value_range *vr = get_value_range (op0); - - /* If we have range information for OP0, then we might be - able to simplify this conditional. */ - if (vr->type == VR_RANGE) - { - tree new_tree = test_for_singularity (cond_code, op0, op1, vr); - if (new_tree) - { - if (dump_file) - { - fprintf (dump_file, "Simplified relational "); - print_gimple_stmt (dump_file, stmt, 0); - fprintf (dump_file, " into "); - } - - gimple_cond_set_code (stmt, EQ_EXPR); - gimple_cond_set_lhs (stmt, op0); - gimple_cond_set_rhs (stmt, new_tree); - - update_stmt (stmt); - - if (dump_file) - { - print_gimple_stmt (dump_file, stmt, 0); - fprintf (dump_file, "\n"); - } - - return true; - } - - /* Try again after inverting the condition. We only deal - with integral types here, so no need to worry about - issues with inverting FP comparisons. */ - new_tree = test_for_singularity - (invert_tree_comparison (cond_code, false), - op0, op1, vr); - if (new_tree) - { - if (dump_file) - { - fprintf (dump_file, "Simplified relational "); - print_gimple_stmt (dump_file, stmt, 0); - fprintf (dump_file, " into "); - } - - gimple_cond_set_code (stmt, NE_EXPR); - gimple_cond_set_lhs (stmt, op0); - gimple_cond_set_rhs (stmt, new_tree); - - update_stmt (stmt); - - if (dump_file) - { - print_gimple_stmt (dump_file, stmt, 0); - fprintf (dump_file, "\n"); - } - - return true; - } - } - } - return false; -} - -/* STMT is a conditional at the end of a basic block. - - If the conditional is of the form SSA_NAME op constant and the SSA_NAME - was set via a type conversion, try to replace the SSA_NAME with the RHS - of the type conversion. Doing so makes the conversion dead which helps - subsequent passes. */ - -static void -simplify_cond_using_ranges_2 (gcond *stmt) -{ - tree op0 = gimple_cond_lhs (stmt); - tree op1 = gimple_cond_rhs (stmt); - - /* If we have a comparison of an SSA_NAME (OP0) against a constant, - see if OP0 was set by a type conversion where the source of - the conversion is another SSA_NAME with a range that fits - into the range of OP0's type. - - If so, the conversion is redundant as the earlier SSA_NAME can be - used for the comparison directly if we just massage the constant in the - comparison. */ - if (TREE_CODE (op0) == SSA_NAME - && TREE_CODE (op1) == INTEGER_CST) - { - gimple *def_stmt = SSA_NAME_DEF_STMT (op0); - tree innerop; - - if (!is_gimple_assign (def_stmt) - || !CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt))) - return; - - innerop = gimple_assign_rhs1 (def_stmt); - - if (TREE_CODE (innerop) == SSA_NAME - && !POINTER_TYPE_P (TREE_TYPE (innerop)) - && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (innerop) - && desired_pro_or_demotion_p (TREE_TYPE (innerop), TREE_TYPE (op0))) - { - value_range *vr = get_value_range (innerop); - - if (range_int_cst_p (vr) - && range_fits_type_p (vr, - TYPE_PRECISION (TREE_TYPE (op0)), - TYPE_SIGN (TREE_TYPE (op0))) - && int_fits_type_p (op1, TREE_TYPE (innerop))) - { - tree newconst = fold_convert (TREE_TYPE (innerop), op1); - gimple_cond_set_lhs (stmt, innerop); - gimple_cond_set_rhs (stmt, newconst); - update_stmt (stmt); - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "Folded into: "); - print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); - fprintf (dump_file, "\n"); - } - } - } - } -} - -/* Simplify a switch statement using the value range of the switch - argument. */ - -static bool -simplify_switch_using_ranges (gswitch *stmt) -{ - tree op = gimple_switch_index (stmt); - value_range *vr = NULL; - bool take_default; - edge e; - edge_iterator ei; - size_t i = 0, j = 0, n, n2; - tree vec2; - switch_update su; - size_t k = 1, l = 0; - - if (TREE_CODE (op) == SSA_NAME) - { - vr = get_value_range (op); - - /* We can only handle integer ranges. */ - if ((vr->type != VR_RANGE - && vr->type != VR_ANTI_RANGE) - || symbolic_range_p (vr)) - return false; - - /* Find case label for min/max of the value range. */ - take_default = !find_case_label_ranges (stmt, vr, &i, &j, &k, &l); - } - else if (TREE_CODE (op) == INTEGER_CST) - { - take_default = !find_case_label_index (stmt, 1, op, &i); - if (take_default) - { - i = 1; - j = 0; - } - else - { - j = i; - } - } - else - return false; - - n = gimple_switch_num_labels (stmt); - - /* We can truncate the case label ranges that partially overlap with OP's - value range. */ - size_t min_idx = 1, max_idx = 0; - if (vr != NULL) - find_case_label_range (stmt, vr->min, vr->max, &min_idx, &max_idx); - if (min_idx <= max_idx) - { - tree min_label = gimple_switch_label (stmt, min_idx); - tree max_label = gimple_switch_label (stmt, max_idx); - - /* Avoid changing the type of the case labels when truncating. */ - tree case_label_type = TREE_TYPE (CASE_LOW (min_label)); - tree vr_min = fold_convert (case_label_type, vr->min); - tree vr_max = fold_convert (case_label_type, vr->max); - - if (vr->type == VR_RANGE) - { - /* If OP's value range is [2,8] and the low label range is - 0 ... 3, truncate the label's range to 2 .. 3. */ - if (tree_int_cst_compare (CASE_LOW (min_label), vr_min) < 0 - && CASE_HIGH (min_label) != NULL_TREE - && tree_int_cst_compare (CASE_HIGH (min_label), vr_min) >= 0) - CASE_LOW (min_label) = vr_min; - - /* If OP's value range is [2,8] and the high label range is - 7 ... 10, truncate the label's range to 7 .. 8. */ - if (tree_int_cst_compare (CASE_LOW (max_label), vr_max) <= 0 - && CASE_HIGH (max_label) != NULL_TREE - && tree_int_cst_compare (CASE_HIGH (max_label), vr_max) > 0) - CASE_HIGH (max_label) = vr_max; - } - else if (vr->type == VR_ANTI_RANGE) - { - tree one_cst = build_one_cst (case_label_type); - - if (min_label == max_label) - { - /* If OP's value range is ~[7,8] and the label's range is - 7 ... 10, truncate the label's range to 9 ... 10. */ - if (tree_int_cst_compare (CASE_LOW (min_label), vr_min) == 0 - && CASE_HIGH (min_label) != NULL_TREE - && tree_int_cst_compare (CASE_HIGH (min_label), vr_max) > 0) - CASE_LOW (min_label) - = int_const_binop (PLUS_EXPR, vr_max, one_cst); - - /* If OP's value range is ~[7,8] and the label's range is - 5 ... 8, truncate the label's range to 5 ... 6. */ - if (tree_int_cst_compare (CASE_LOW (min_label), vr_min) < 0 - && CASE_HIGH (min_label) != NULL_TREE - && tree_int_cst_compare (CASE_HIGH (min_label), vr_max) == 0) - CASE_HIGH (min_label) - = int_const_binop (MINUS_EXPR, vr_min, one_cst); - } - else - { - /* If OP's value range is ~[2,8] and the low label range is - 0 ... 3, truncate the label's range to 0 ... 1. */ - if (tree_int_cst_compare (CASE_LOW (min_label), vr_min) < 0 - && CASE_HIGH (min_label) != NULL_TREE - && tree_int_cst_compare (CASE_HIGH (min_label), vr_min) >= 0) - CASE_HIGH (min_label) - = int_const_binop (MINUS_EXPR, vr_min, one_cst); - - /* If OP's value range is ~[2,8] and the high label range is - 7 ... 10, truncate the label's range to 9 ... 10. */ - if (tree_int_cst_compare (CASE_LOW (max_label), vr_max) <= 0 - && CASE_HIGH (max_label) != NULL_TREE - && tree_int_cst_compare (CASE_HIGH (max_label), vr_max) > 0) - CASE_LOW (max_label) - = int_const_binop (PLUS_EXPR, vr_max, one_cst); - } - } - - /* Canonicalize singleton case ranges. */ - if (tree_int_cst_equal (CASE_LOW (min_label), CASE_HIGH (min_label))) - CASE_HIGH (min_label) = NULL_TREE; - if (tree_int_cst_equal (CASE_LOW (max_label), CASE_HIGH (max_label))) - CASE_HIGH (max_label) = NULL_TREE; - } - - /* We can also eliminate case labels that lie completely outside OP's value - range. */ - - /* Bail out if this is just all edges taken. */ - if (i == 1 - && j == n - 1 - && take_default) - return false; - - /* Build a new vector of taken case labels. */ - vec2 = make_tree_vec (j - i + 1 + l - k + 1 + (int)take_default); - n2 = 0; - - /* Add the default edge, if necessary. */ - if (take_default) - TREE_VEC_ELT (vec2, n2++) = gimple_switch_default_label (stmt); - - for (; i <= j; ++i, ++n2) - TREE_VEC_ELT (vec2, n2) = gimple_switch_label (stmt, i); - - for (; k <= l; ++k, ++n2) - TREE_VEC_ELT (vec2, n2) = gimple_switch_label (stmt, k); - - /* Mark needed edges. */ - for (i = 0; i < n2; ++i) - { - e = find_edge (gimple_bb (stmt), - label_to_block (CASE_LABEL (TREE_VEC_ELT (vec2, i)))); - e->aux = (void *)-1; - } - - /* Queue not needed edges for later removal. */ - FOR_EACH_EDGE (e, ei, gimple_bb (stmt)->succs) - { - if (e->aux == (void *)-1) - { - e->aux = NULL; - continue; - } - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "removing unreachable case label\n"); - } - to_remove_edges.safe_push (e); - e->flags &= ~EDGE_EXECUTABLE; - } - - /* And queue an update for the stmt. */ - su.stmt = stmt; - su.vec = vec2; - to_update_switch_stmts.safe_push (su); - return false; -} - -/* Simplify an integral conversion from an SSA name in STMT. */ - -static bool -simplify_conversion_using_ranges (gimple_stmt_iterator *gsi, gimple *stmt) -{ - tree innerop, middleop, finaltype; - gimple *def_stmt; - signop inner_sgn, middle_sgn, final_sgn; - unsigned inner_prec, middle_prec, final_prec; - widest_int innermin, innermed, innermax, middlemin, middlemed, middlemax; - - finaltype = TREE_TYPE (gimple_assign_lhs (stmt)); - if (!INTEGRAL_TYPE_P (finaltype)) - return false; - middleop = gimple_assign_rhs1 (stmt); - def_stmt = SSA_NAME_DEF_STMT (middleop); - if (!is_gimple_assign (def_stmt) - || !CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def_stmt))) - return false; - innerop = gimple_assign_rhs1 (def_stmt); - if (TREE_CODE (innerop) != SSA_NAME - || SSA_NAME_OCCURS_IN_ABNORMAL_PHI (innerop)) - return false; - - /* Get the value-range of the inner operand. Use get_range_info in - case innerop was created during substitute-and-fold. */ - wide_int imin, imax; - if (!INTEGRAL_TYPE_P (TREE_TYPE (innerop)) - || get_range_info (innerop, &imin, &imax) != VR_RANGE) - return false; - innermin = widest_int::from (imin, TYPE_SIGN (TREE_TYPE (innerop))); - innermax = widest_int::from (imax, TYPE_SIGN (TREE_TYPE (innerop))); - - /* Simulate the conversion chain to check if the result is equal if - the middle conversion is removed. */ - inner_prec = TYPE_PRECISION (TREE_TYPE (innerop)); - middle_prec = TYPE_PRECISION (TREE_TYPE (middleop)); - final_prec = TYPE_PRECISION (finaltype); - - /* If the first conversion is not injective, the second must not - be widening. */ - if (wi::gtu_p (innermax - innermin, - wi::mask <widest_int> (middle_prec, false)) - && middle_prec < final_prec) - return false; - /* We also want a medium value so that we can track the effect that - narrowing conversions with sign change have. */ - inner_sgn = TYPE_SIGN (TREE_TYPE (innerop)); - if (inner_sgn == UNSIGNED) - innermed = wi::shifted_mask <widest_int> (1, inner_prec - 1, false); - else - innermed = 0; - if (wi::cmp (innermin, innermed, inner_sgn) >= 0 - || wi::cmp (innermed, innermax, inner_sgn) >= 0) - innermed = innermin; - - middle_sgn = TYPE_SIGN (TREE_TYPE (middleop)); - middlemin = wi::ext (innermin, middle_prec, middle_sgn); - middlemed = wi::ext (innermed, middle_prec, middle_sgn); - middlemax = wi::ext (innermax, middle_prec, middle_sgn); - - /* Require that the final conversion applied to both the original - and the intermediate range produces the same result. */ - final_sgn = TYPE_SIGN (finaltype); - if (wi::ext (middlemin, final_prec, final_sgn) - != wi::ext (innermin, final_prec, final_sgn) - || wi::ext (middlemed, final_prec, final_sgn) - != wi::ext (innermed, final_prec, final_sgn) - || wi::ext (middlemax, final_prec, final_sgn) - != wi::ext (innermax, final_prec, final_sgn)) - return false; - - gimple_assign_set_rhs1 (stmt, innerop); - fold_stmt (gsi, follow_single_use_edges); - return true; -} - -/* Simplify a conversion from integral SSA name to float in STMT. */ - -static bool -simplify_float_conversion_using_ranges (gimple_stmt_iterator *gsi, - gimple *stmt) -{ - tree rhs1 = gimple_assign_rhs1 (stmt); - value_range *vr = get_value_range (rhs1); - scalar_float_mode fltmode - = SCALAR_FLOAT_TYPE_MODE (TREE_TYPE (gimple_assign_lhs (stmt))); - scalar_int_mode mode; - tree tem; - gassign *conv; - - /* We can only handle constant ranges. */ - if (vr->type != VR_RANGE - || TREE_CODE (vr->min) != INTEGER_CST - || TREE_CODE (vr->max) != INTEGER_CST) - return false; - - /* First check if we can use a signed type in place of an unsigned. */ - scalar_int_mode rhs_mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (rhs1)); - if (TYPE_UNSIGNED (TREE_TYPE (rhs1)) - && can_float_p (fltmode, rhs_mode, 0) != CODE_FOR_nothing - && range_fits_type_p (vr, TYPE_PRECISION (TREE_TYPE (rhs1)), SIGNED)) - mode = rhs_mode; - /* If we can do the conversion in the current input mode do nothing. */ - else if (can_float_p (fltmode, rhs_mode, - TYPE_UNSIGNED (TREE_TYPE (rhs1))) != CODE_FOR_nothing) - return false; - /* Otherwise search for a mode we can use, starting from the narrowest - integer mode available. */ - else - { - mode = NARROWEST_INT_MODE; - for (;;) - { - /* If we cannot do a signed conversion to float from mode - or if the value-range does not fit in the signed type - try with a wider mode. */ - if (can_float_p (fltmode, mode, 0) != CODE_FOR_nothing - && range_fits_type_p (vr, GET_MODE_PRECISION (mode), SIGNED)) - break; - - /* But do not widen the input. Instead leave that to the - optabs expansion code. */ - if (!GET_MODE_WIDER_MODE (mode).exists (&mode) - || GET_MODE_PRECISION (mode) > TYPE_PRECISION (TREE_TYPE (rhs1))) - return false; - } - } - - /* It works, insert a truncation or sign-change before the - float conversion. */ - tem = make_ssa_name (build_nonstandard_integer_type - (GET_MODE_PRECISION (mode), 0)); - conv = gimple_build_assign (tem, NOP_EXPR, rhs1); - gsi_insert_before (gsi, conv, GSI_SAME_STMT); - gimple_assign_set_rhs1 (stmt, tem); - fold_stmt (gsi, follow_single_use_edges); - - return true; -} - -/* Simplify an internal fn call using ranges if possible. */ - -static bool -simplify_internal_call_using_ranges (gimple_stmt_iterator *gsi, gimple *stmt) -{ - enum tree_code subcode; - bool is_ubsan = false; - bool ovf = false; - switch (gimple_call_internal_fn (stmt)) - { - case IFN_UBSAN_CHECK_ADD: - subcode = PLUS_EXPR; - is_ubsan = true; - break; - case IFN_UBSAN_CHECK_SUB: - subcode = MINUS_EXPR; - is_ubsan = true; - break; - case IFN_UBSAN_CHECK_MUL: - subcode = MULT_EXPR; - is_ubsan = true; - break; - case IFN_ADD_OVERFLOW: - subcode = PLUS_EXPR; - break; - case IFN_SUB_OVERFLOW: - subcode = MINUS_EXPR; - break; - case IFN_MUL_OVERFLOW: - subcode = MULT_EXPR; - break; - default: - return false; - } - - tree op0 = gimple_call_arg (stmt, 0); - tree op1 = gimple_call_arg (stmt, 1); - tree type; - if (is_ubsan) - { - type = TREE_TYPE (op0); - if (VECTOR_TYPE_P (type)) - return false; - } - else if (gimple_call_lhs (stmt) == NULL_TREE) - return false; - else - type = TREE_TYPE (TREE_TYPE (gimple_call_lhs (stmt))); - if (!check_for_binary_op_overflow (subcode, type, op0, op1, &ovf) - || (is_ubsan && ovf)) - return false; - - gimple *g; - location_t loc = gimple_location (stmt); - if (is_ubsan) - g = gimple_build_assign (gimple_call_lhs (stmt), subcode, op0, op1); - else - { - int prec = TYPE_PRECISION (type); - tree utype = type; - if (ovf - || !useless_type_conversion_p (type, TREE_TYPE (op0)) - || !useless_type_conversion_p (type, TREE_TYPE (op1))) - utype = build_nonstandard_integer_type (prec, 1); - if (TREE_CODE (op0) == INTEGER_CST) - op0 = fold_convert (utype, op0); - else if (!useless_type_conversion_p (utype, TREE_TYPE (op0))) - { - g = gimple_build_assign (make_ssa_name (utype), NOP_EXPR, op0); - gimple_set_location (g, loc); - gsi_insert_before (gsi, g, GSI_SAME_STMT); - op0 = gimple_assign_lhs (g); - } - if (TREE_CODE (op1) == INTEGER_CST) - op1 = fold_convert (utype, op1); - else if (!useless_type_conversion_p (utype, TREE_TYPE (op1))) - { - g = gimple_build_assign (make_ssa_name (utype), NOP_EXPR, op1); - gimple_set_location (g, loc); - gsi_insert_before (gsi, g, GSI_SAME_STMT); - op1 = gimple_assign_lhs (g); - } - g = gimple_build_assign (make_ssa_name (utype), subcode, op0, op1); - gimple_set_location (g, loc); - gsi_insert_before (gsi, g, GSI_SAME_STMT); - if (utype != type) - { - g = gimple_build_assign (make_ssa_name (type), NOP_EXPR, - gimple_assign_lhs (g)); - gimple_set_location (g, loc); - gsi_insert_before (gsi, g, GSI_SAME_STMT); - } - g = gimple_build_assign (gimple_call_lhs (stmt), COMPLEX_EXPR, - gimple_assign_lhs (g), - build_int_cst (type, ovf)); - } - gimple_set_location (g, loc); - gsi_replace (gsi, g, false); - return true; -} - -/* Return true if VAR is a two-valued variable. Set a and b with the - two-values when it is true. Return false otherwise. */ - -static bool -two_valued_val_range_p (tree var, tree *a, tree *b) -{ - value_range *vr = get_value_range (var); - if ((vr->type != VR_RANGE - && vr->type != VR_ANTI_RANGE) - || TREE_CODE (vr->min) != INTEGER_CST - || TREE_CODE (vr->max) != INTEGER_CST) - return false; - - if (vr->type == VR_RANGE - && wi::to_wide (vr->max) - wi::to_wide (vr->min) == 1) - { - *a = vr->min; - *b = vr->max; - return true; - } - - /* ~[TYPE_MIN + 1, TYPE_MAX - 1] */ - if (vr->type == VR_ANTI_RANGE - && (wi::to_wide (vr->min) - - wi::to_wide (vrp_val_min (TREE_TYPE (var)))) == 1 - && (wi::to_wide (vrp_val_max (TREE_TYPE (var))) - - wi::to_wide (vr->max)) == 1) - { - *a = vrp_val_min (TREE_TYPE (var)); - *b = vrp_val_max (TREE_TYPE (var)); - return true; - } - - return false; -} - -/* Simplify STMT using ranges if possible. */ - -static bool -simplify_stmt_using_ranges (gimple_stmt_iterator *gsi) +class vrp_folder : public substitute_and_fold_engine { - gimple *stmt = gsi_stmt (*gsi); - if (is_gimple_assign (stmt)) - { - enum tree_code rhs_code = gimple_assign_rhs_code (stmt); - tree rhs1 = gimple_assign_rhs1 (stmt); - tree rhs2 = gimple_assign_rhs2 (stmt); - tree lhs = gimple_assign_lhs (stmt); - tree val1 = NULL_TREE, val2 = NULL_TREE; - use_operand_p use_p; - gimple *use_stmt; - - /* Convert: - LHS = CST BINOP VAR - Where VAR is two-valued and LHS is used in GIMPLE_COND only - To: - LHS = VAR == VAL1 ? (CST BINOP VAL1) : (CST BINOP VAL2) - - Also handles: - LHS = VAR BINOP CST - Where VAR is two-valued and LHS is used in GIMPLE_COND only - To: - LHS = VAR == VAL1 ? (VAL1 BINOP CST) : (VAL2 BINOP CST) */ - - if (TREE_CODE_CLASS (rhs_code) == tcc_binary - && INTEGRAL_TYPE_P (TREE_TYPE (lhs)) - && ((TREE_CODE (rhs1) == INTEGER_CST - && TREE_CODE (rhs2) == SSA_NAME) - || (TREE_CODE (rhs2) == INTEGER_CST - && TREE_CODE (rhs1) == SSA_NAME)) - && single_imm_use (lhs, &use_p, &use_stmt) - && gimple_code (use_stmt) == GIMPLE_COND) - - { - tree new_rhs1 = NULL_TREE; - tree new_rhs2 = NULL_TREE; - tree cmp_var = NULL_TREE; - - if (TREE_CODE (rhs2) == SSA_NAME - && two_valued_val_range_p (rhs2, &val1, &val2)) - { - /* Optimize RHS1 OP [VAL1, VAL2]. */ - new_rhs1 = int_const_binop (rhs_code, rhs1, val1); - new_rhs2 = int_const_binop (rhs_code, rhs1, val2); - cmp_var = rhs2; - } - else if (TREE_CODE (rhs1) == SSA_NAME - && two_valued_val_range_p (rhs1, &val1, &val2)) - { - /* Optimize [VAL1, VAL2] OP RHS2. */ - new_rhs1 = int_const_binop (rhs_code, val1, rhs2); - new_rhs2 = int_const_binop (rhs_code, val2, rhs2); - cmp_var = rhs1; - } - - /* If we could not find two-vals or the optimzation is invalid as - in divide by zero, new_rhs1 / new_rhs will be NULL_TREE. */ - if (new_rhs1 && new_rhs2) - { - tree cond = build2 (EQ_EXPR, boolean_type_node, cmp_var, val1); - gimple_assign_set_rhs_with_ops (gsi, - COND_EXPR, cond, - new_rhs1, - new_rhs2); - update_stmt (gsi_stmt (*gsi)); - fold_stmt (gsi, follow_single_use_edges); - return true; - } - } - - switch (rhs_code) - { - case EQ_EXPR: - case NE_EXPR: - /* Transform EQ_EXPR, NE_EXPR into BIT_XOR_EXPR or identity - if the RHS is zero or one, and the LHS are known to be boolean - values. */ - if (INTEGRAL_TYPE_P (TREE_TYPE (rhs1))) - return simplify_truth_ops_using_ranges (gsi, stmt); - break; - - /* Transform TRUNC_DIV_EXPR and TRUNC_MOD_EXPR into RSHIFT_EXPR - and BIT_AND_EXPR respectively if the first operand is greater - than zero and the second operand is an exact power of two. - Also optimize TRUNC_MOD_EXPR away if the second operand is - constant and the first operand already has the right value - range. */ - case TRUNC_DIV_EXPR: - case TRUNC_MOD_EXPR: - if ((TREE_CODE (rhs1) == SSA_NAME - || TREE_CODE (rhs1) == INTEGER_CST) - && INTEGRAL_TYPE_P (TREE_TYPE (rhs1))) - return simplify_div_or_mod_using_ranges (gsi, stmt); - break; - - /* Transform ABS (X) into X or -X as appropriate. */ - case ABS_EXPR: - if (TREE_CODE (rhs1) == SSA_NAME - && INTEGRAL_TYPE_P (TREE_TYPE (rhs1))) - return simplify_abs_using_ranges (gsi, stmt); - break; - - case BIT_AND_EXPR: - case BIT_IOR_EXPR: - /* Optimize away BIT_AND_EXPR and BIT_IOR_EXPR - if all the bits being cleared are already cleared or - all the bits being set are already set. */ - if (INTEGRAL_TYPE_P (TREE_TYPE (rhs1))) - return simplify_bit_ops_using_ranges (gsi, stmt); - break; - - CASE_CONVERT: - if (TREE_CODE (rhs1) == SSA_NAME - && INTEGRAL_TYPE_P (TREE_TYPE (rhs1))) - return simplify_conversion_using_ranges (gsi, stmt); - break; - - case FLOAT_EXPR: - if (TREE_CODE (rhs1) == SSA_NAME - && INTEGRAL_TYPE_P (TREE_TYPE (rhs1))) - return simplify_float_conversion_using_ranges (gsi, stmt); - break; - - case MIN_EXPR: - case MAX_EXPR: - return simplify_min_or_max_using_ranges (gsi, stmt); - - default: - break; - } - } - else if (gimple_code (stmt) == GIMPLE_COND) - return simplify_cond_using_ranges_1 (as_a <gcond *> (stmt)); - else if (gimple_code (stmt) == GIMPLE_SWITCH) - return simplify_switch_using_ranges (as_a <gswitch *> (stmt)); - else if (is_gimple_call (stmt) - && gimple_call_internal_p (stmt)) - return simplify_internal_call_using_ranges (gsi, stmt); - - return false; -} + public: + tree get_value (tree) FINAL OVERRIDE; + bool fold_stmt (gimple_stmt_iterator *) FINAL OVERRIDE; + bool fold_predicate_in (gimple_stmt_iterator *); + + class vr_values *vr_values; + + /* Delegators. */ + tree vrp_evaluate_conditional (tree_code code, tree op0, + tree op1, gimple *stmt) + { return vr_values->vrp_evaluate_conditional (code, op0, op1, stmt); } + bool simplify_stmt_using_ranges (gimple_stmt_iterator *gsi) + { return vr_values->simplify_stmt_using_ranges (gsi); } + tree op_with_constant_singleton_value_range (tree op) + { return vr_values->op_with_constant_singleton_value_range (op); } +}; /* If the statement pointed by SI has a predicate whose value can be computed using the value range information computed by VRP, compute its value and return true. Otherwise, return false. */ -static bool -fold_predicate_in (gimple_stmt_iterator *si) +bool +vrp_folder::fold_predicate_in (gimple_stmt_iterator *si) { bool assignment_p = false; tree val; @@ -10526,13 +6412,6 @@ fold_predicate_in (gimple_stmt_iterator *si) return false; } -class vrp_folder : public substitute_and_fold_engine -{ - public: - tree get_value (tree) FINAL OVERRIDE; - bool fold_stmt (gimple_stmt_iterator *) FINAL OVERRIDE; -}; - /* Callback for substitute_and_fold folding the stmt at *SI. */ bool @@ -10583,6 +6462,9 @@ lhs_of_dominating_assert (tree op, basic_block bb, gimple *stmt) return op; } +/* A hack. */ +static class vr_values *x_vr_values; + /* A trivial wrapper so that we can present the generic jump threading code with a simple API for simplifying statements. STMT is the statement we want to simplify, WITHIN_STMT provides the location @@ -10598,6 +6480,7 @@ simplify_stmt_for_jump_threading (gimple *stmt, gimple *within_stmt, if (cached_lhs && is_gimple_min_invariant (cached_lhs)) return cached_lhs; + vr_values *vr_values = x_vr_values; if (gcond *cond_stmt = dyn_cast <gcond *> (stmt)) { tree op0 = gimple_cond_lhs (cond_stmt); @@ -10606,8 +6489,8 @@ simplify_stmt_for_jump_threading (gimple *stmt, gimple *within_stmt, tree op1 = gimple_cond_rhs (cond_stmt); op1 = lhs_of_dominating_assert (op1, bb, stmt); - return vrp_evaluate_conditional (gimple_cond_code (cond_stmt), - op0, op1, within_stmt); + return vr_values->vrp_evaluate_conditional (gimple_cond_code (cond_stmt), + op0, op1, within_stmt); } /* We simplify a switch statement by trying to determine which case label @@ -10621,7 +6504,7 @@ simplify_stmt_for_jump_threading (gimple *stmt, gimple *within_stmt, op = lhs_of_dominating_assert (op, bb, stmt); - value_range *vr = get_value_range (op); + value_range *vr = vr_values->get_value_range (op); if ((vr->type != VR_RANGE && vr->type != VR_ANTI_RANGE) || symbolic_range_p (vr)) return NULL_TREE; @@ -10682,7 +6565,7 @@ simplify_stmt_for_jump_threading (gimple *stmt, gimple *within_stmt, && (INTEGRAL_TYPE_P (TREE_TYPE (lhs)) || POINTER_TYPE_P (TREE_TYPE (lhs)))) { - extract_range_from_assignment (&new_vr, assign_stmt); + vr_values->extract_range_from_assignment (&new_vr, assign_stmt); if (range_int_cst_singleton_p (&new_vr)) return new_vr.min; } @@ -10705,11 +6588,14 @@ public: virtual edge before_dom_children (basic_block); virtual void after_dom_children (basic_block); + class vr_values *vr_values; + private: class const_and_copies *m_const_and_copies; class avail_exprs_stack *m_avail_exprs_stack; gcond *m_dummy_cond; + }; /* Called before processing dominator children of BB. We want to look @@ -10762,9 +6648,11 @@ vrp_dom_walker::after_dom_children (basic_block bb) integer_zero_node, integer_zero_node, NULL, NULL); + x_vr_values = vr_values; thread_outgoing_edges (bb, m_dummy_cond, m_const_and_copies, m_avail_exprs_stack, simplify_stmt_for_jump_threading); + x_vr_values = NULL; m_avail_exprs_stack->pop_to_marker (); m_const_and_copies->pop_to_marker (); @@ -10791,7 +6679,7 @@ vrp_dom_walker::after_dom_children (basic_block bb) for later realization. */ static void -identify_jump_threads (void) +identify_jump_threads (class vr_values *vr_values) { int i; edge e; @@ -10823,6 +6711,7 @@ identify_jump_threads (void) = new class avail_exprs_stack (avail_exprs); vrp_dom_walker walker (CDI_DOMINATORS, equiv_stack, avail_exprs_stack); + walker.vr_values = vr_values; walker.walk (cfun->cfg->x_entry_block_ptr); /* Clear EDGE_IGNORE. */ @@ -10837,572 +6726,57 @@ identify_jump_threads (void) delete avail_exprs_stack; } -/* Free VRP lattice. */ - -static void -vrp_free_lattice () -{ - /* Free allocated memory. */ - free (vr_value); - free (vr_phi_edge_counts); - bitmap_obstack_release (&vrp_equiv_obstack); - vrp_value_range_pool.release (); - - /* So that we can distinguish between VRP data being available - and not available. */ - vr_value = NULL; - vr_phi_edge_counts = NULL; -} - /* Traverse all the blocks folding conditionals with known ranges. */ -static void -vrp_finalize (bool warn_array_bounds_p) +void +vrp_prop::vrp_finalize (bool warn_array_bounds_p) { size_t i; - values_propagated = true; + vr_values.values_propagated = true; if (dump_file) { fprintf (dump_file, "\nValue ranges after VRP:\n\n"); - dump_all_value_ranges (dump_file); + vr_values.dump_all_value_ranges (dump_file); fprintf (dump_file, "\n"); } /* Set value range to non pointer SSA_NAMEs. */ - for (i = 0; i < num_vr_values; i++) - if (vr_value[i]) - { - tree name = ssa_name (i); + for (i = 0; i < num_ssa_names; i++) + { + tree name = ssa_name (i); + if (!name) + continue; - if (!name - || (vr_value[i]->type == VR_VARYING) - || (vr_value[i]->type == VR_UNDEFINED) - || (TREE_CODE (vr_value[i]->min) != INTEGER_CST) - || (TREE_CODE (vr_value[i]->max) != INTEGER_CST)) - continue; + value_range *vr = get_value_range (name); + if (!name + || (vr->type == VR_VARYING) + || (vr->type == VR_UNDEFINED) + || (TREE_CODE (vr->min) != INTEGER_CST) + || (TREE_CODE (vr->max) != INTEGER_CST)) + continue; - if (POINTER_TYPE_P (TREE_TYPE (name)) - && ((vr_value[i]->type == VR_RANGE - && range_includes_zero_p (vr_value[i]->min, - vr_value[i]->max) == 0) - || (vr_value[i]->type == VR_ANTI_RANGE - && range_includes_zero_p (vr_value[i]->min, - vr_value[i]->max) == 1))) - set_ptr_nonnull (name); - else if (!POINTER_TYPE_P (TREE_TYPE (name))) - set_range_info (name, vr_value[i]->type, - wi::to_wide (vr_value[i]->min), - wi::to_wide (vr_value[i]->max)); - } + if (POINTER_TYPE_P (TREE_TYPE (name)) + && ((vr->type == VR_RANGE + && range_includes_zero_p (vr->min, vr->max) == 0) + || (vr->type == VR_ANTI_RANGE + && range_includes_zero_p (vr->min, vr->max) == 1))) + set_ptr_nonnull (name); + else if (!POINTER_TYPE_P (TREE_TYPE (name))) + set_range_info (name, vr->type, + wi::to_wide (vr->min), + wi::to_wide (vr->max)); + } class vrp_folder vrp_folder; + vrp_folder.vr_values = &vr_values; vrp_folder.substitute_and_fold (); if (warn_array_bounds && warn_array_bounds_p) check_all_array_refs (); } -/* evrp_dom_walker visits the basic blocks in the dominance order and set - the Value Ranges (VR) for SSA_NAMEs in the scope. Use this VR to - discover more VRs. */ - -class evrp_dom_walker : public dom_walker -{ -public: - evrp_dom_walker () - : dom_walker (CDI_DOMINATORS), stack (10) - { - need_eh_cleanup = BITMAP_ALLOC (NULL); - } - ~evrp_dom_walker () - { - BITMAP_FREE (need_eh_cleanup); - } - virtual edge before_dom_children (basic_block); - virtual void after_dom_children (basic_block); - void push_value_range (tree var, value_range *vr); - value_range *pop_value_range (tree var); - value_range *try_find_new_range (tree, tree op, tree_code code, tree limit); - - /* Cond_stack holds the old VR. */ - auto_vec<std::pair <tree, value_range*> > stack; - bitmap need_eh_cleanup; - auto_vec<gimple *> stmts_to_fixup; - auto_vec<gimple *> stmts_to_remove; -}; - -/* Find new range for NAME such that (OP CODE LIMIT) is true. */ - -value_range * -evrp_dom_walker::try_find_new_range (tree name, - tree op, tree_code code, tree limit) -{ - value_range vr = VR_INITIALIZER; - value_range *old_vr = get_value_range (name); - - /* Discover VR when condition is true. */ - extract_range_for_var_from_comparison_expr (name, code, op, - limit, &vr); - /* If we found any usable VR, set the VR to ssa_name and create a - PUSH old value in the stack with the old VR. */ - if (vr.type == VR_RANGE || vr.type == VR_ANTI_RANGE) - { - if (old_vr->type == vr.type - && vrp_operand_equal_p (old_vr->min, vr.min) - && vrp_operand_equal_p (old_vr->max, vr.max)) - return NULL; - value_range *new_vr = vrp_value_range_pool.allocate (); - *new_vr = vr; - return new_vr; - } - return NULL; -} - -/* See if there is any new scope is entered with new VR and set that VR to - ssa_name before visiting the statements in the scope. */ - -edge -evrp_dom_walker::before_dom_children (basic_block bb) -{ - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, "Visiting BB%d\n", bb->index); - - stack.safe_push (std::make_pair (NULL_TREE, (value_range *)NULL)); - - edge pred_e = single_pred_edge_ignoring_loop_edges (bb, false); - if (pred_e) - { - gimple *stmt = last_stmt (pred_e->src); - tree op0 = NULL_TREE; - - if (stmt - && gimple_code (stmt) == GIMPLE_COND - && (op0 = gimple_cond_lhs (stmt)) - && TREE_CODE (op0) == SSA_NAME - && (INTEGRAL_TYPE_P (TREE_TYPE (gimple_cond_lhs (stmt))) - || POINTER_TYPE_P (TREE_TYPE (gimple_cond_lhs (stmt))))) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "Visiting controlling predicate "); - print_gimple_stmt (dump_file, stmt, 0); - } - /* Entering a new scope. Try to see if we can find a VR - here. */ - tree op1 = gimple_cond_rhs (stmt); - if (TREE_OVERFLOW_P (op1)) - op1 = drop_tree_overflow (op1); - tree_code code = gimple_cond_code (stmt); - - auto_vec<assert_info, 8> asserts; - register_edge_assert_for (op0, pred_e, code, op0, op1, asserts); - if (TREE_CODE (op1) == SSA_NAME) - register_edge_assert_for (op1, pred_e, code, op0, op1, asserts); - - auto_vec<std::pair<tree, value_range *>, 8> vrs; - for (unsigned i = 0; i < asserts.length (); ++i) - { - value_range *vr = try_find_new_range (asserts[i].name, - asserts[i].expr, - asserts[i].comp_code, - asserts[i].val); - if (vr) - vrs.safe_push (std::make_pair (asserts[i].name, vr)); - } - /* Push updated ranges only after finding all of them to avoid - ordering issues that can lead to worse ranges. */ - for (unsigned i = 0; i < vrs.length (); ++i) - push_value_range (vrs[i].first, vrs[i].second); - } - } - - /* Visit PHI stmts and discover any new VRs possible. */ - bool has_unvisited_preds = false; - edge_iterator ei; - edge e; - FOR_EACH_EDGE (e, ei, bb->preds) - if (e->flags & EDGE_EXECUTABLE - && !(e->src->flags & BB_VISITED)) - { - has_unvisited_preds = true; - break; - } - - for (gphi_iterator gpi = gsi_start_phis (bb); - !gsi_end_p (gpi); gsi_next (&gpi)) - { - gphi *phi = gpi.phi (); - tree lhs = PHI_RESULT (phi); - if (virtual_operand_p (lhs)) - continue; - value_range vr_result = VR_INITIALIZER; - bool interesting = stmt_interesting_for_vrp (phi); - if (interesting && dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "Visiting PHI node "); - print_gimple_stmt (dump_file, phi, 0); - } - if (!has_unvisited_preds - && interesting) - extract_range_from_phi_node (phi, &vr_result); - else - { - set_value_range_to_varying (&vr_result); - /* When we have an unvisited executable predecessor we can't - use PHI arg ranges which may be still UNDEFINED but have - to use VARYING for them. But we can still resort to - SCEV for loop header PHIs. */ - struct loop *l; - if (interesting - && (l = loop_containing_stmt (phi)) - && l->header == gimple_bb (phi)) - adjust_range_with_scev (&vr_result, l, phi, lhs); - } - update_value_range (lhs, &vr_result); - - /* Mark PHIs whose lhs we fully propagate for removal. */ - tree val = op_with_constant_singleton_value_range (lhs); - if (val && may_propagate_copy (lhs, val)) - { - stmts_to_remove.safe_push (phi); - continue; - } - - /* Set the SSA with the value range. */ - if (INTEGRAL_TYPE_P (TREE_TYPE (lhs))) - { - if ((vr_result.type == VR_RANGE - || vr_result.type == VR_ANTI_RANGE) - && (TREE_CODE (vr_result.min) == INTEGER_CST) - && (TREE_CODE (vr_result.max) == INTEGER_CST)) - set_range_info (lhs, vr_result.type, - wi::to_wide (vr_result.min), - wi::to_wide (vr_result.max)); - } - else if (POINTER_TYPE_P (TREE_TYPE (lhs)) - && ((vr_result.type == VR_RANGE - && range_includes_zero_p (vr_result.min, - vr_result.max) == 0) - || (vr_result.type == VR_ANTI_RANGE - && range_includes_zero_p (vr_result.min, - vr_result.max) == 1))) - set_ptr_nonnull (lhs); - } - - edge taken_edge = NULL; - - /* Visit all other stmts and discover any new VRs possible. */ - for (gimple_stmt_iterator gsi = gsi_start_bb (bb); - !gsi_end_p (gsi); gsi_next (&gsi)) - { - gimple *stmt = gsi_stmt (gsi); - tree output = NULL_TREE; - gimple *old_stmt = stmt; - bool was_noreturn = (is_gimple_call (stmt) - && gimple_call_noreturn_p (stmt)); - - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "Visiting stmt "); - print_gimple_stmt (dump_file, stmt, 0); - } - - if (gcond *cond = dyn_cast <gcond *> (stmt)) - { - vrp_visit_cond_stmt (cond, &taken_edge); - if (taken_edge) - { - if (taken_edge->flags & EDGE_TRUE_VALUE) - gimple_cond_make_true (cond); - else if (taken_edge->flags & EDGE_FALSE_VALUE) - gimple_cond_make_false (cond); - else - gcc_unreachable (); - update_stmt (stmt); - } - } - else if (stmt_interesting_for_vrp (stmt)) - { - edge taken_edge; - value_range vr = VR_INITIALIZER; - extract_range_from_stmt (stmt, &taken_edge, &output, &vr); - if (output - && (vr.type == VR_RANGE || vr.type == VR_ANTI_RANGE)) - { - update_value_range (output, &vr); - vr = *get_value_range (output); - - /* Mark stmts whose output we fully propagate for removal. */ - tree val; - if ((val = op_with_constant_singleton_value_range (output)) - && may_propagate_copy (output, val) - && !stmt_could_throw_p (stmt) - && !gimple_has_side_effects (stmt)) - { - stmts_to_remove.safe_push (stmt); - continue; - } - - /* Set the SSA with the value range. */ - if (INTEGRAL_TYPE_P (TREE_TYPE (output))) - { - if ((vr.type == VR_RANGE - || vr.type == VR_ANTI_RANGE) - && (TREE_CODE (vr.min) == INTEGER_CST) - && (TREE_CODE (vr.max) == INTEGER_CST)) - set_range_info (output, vr.type, - wi::to_wide (vr.min), - wi::to_wide (vr.max)); - } - else if (POINTER_TYPE_P (TREE_TYPE (output)) - && ((vr.type == VR_RANGE - && range_includes_zero_p (vr.min, - vr.max) == 0) - || (vr.type == VR_ANTI_RANGE - && range_includes_zero_p (vr.min, - vr.max) == 1))) - set_ptr_nonnull (output); - } - else - set_defs_to_varying (stmt); - } - else - set_defs_to_varying (stmt); - - /* See if we can derive a range for any of STMT's operands. */ - tree op; - ssa_op_iter i; - FOR_EACH_SSA_TREE_OPERAND (op, stmt, i, SSA_OP_USE) - { - tree value; - enum tree_code comp_code; - - /* If OP is used in such a way that we can infer a value - range for it, and we don't find a previous assertion for - it, create a new assertion location node for OP. */ - if (infer_value_range (stmt, op, &comp_code, &value)) - { - /* If we are able to infer a nonzero value range for OP, - then walk backwards through the use-def chain to see if OP - was set via a typecast. - If so, then we can also infer a nonzero value range - for the operand of the NOP_EXPR. */ - if (comp_code == NE_EXPR && integer_zerop (value)) - { - tree t = op; - gimple *def_stmt = SSA_NAME_DEF_STMT (t); - while (is_gimple_assign (def_stmt) - && CONVERT_EXPR_CODE_P - (gimple_assign_rhs_code (def_stmt)) - && TREE_CODE - (gimple_assign_rhs1 (def_stmt)) == SSA_NAME - && POINTER_TYPE_P - (TREE_TYPE (gimple_assign_rhs1 (def_stmt)))) - { - t = gimple_assign_rhs1 (def_stmt); - def_stmt = SSA_NAME_DEF_STMT (t); - - /* Add VR when (T COMP_CODE value) condition is - true. */ - value_range *op_range - = try_find_new_range (t, t, comp_code, value); - if (op_range) - push_value_range (t, op_range); - } - } - /* Add VR when (OP COMP_CODE value) condition is true. */ - value_range *op_range = try_find_new_range (op, op, - comp_code, value); - if (op_range) - push_value_range (op, op_range); - } - } - - /* Try folding stmts with the VR discovered. */ - class vrp_folder vrp_folder; - bool did_replace = vrp_folder.replace_uses_in (stmt); - if (fold_stmt (&gsi, follow_single_use_edges) - || did_replace) - { - stmt = gsi_stmt (gsi); - update_stmt (stmt); - did_replace = true; - } - - if (did_replace) - { - /* If we cleaned up EH information from the statement, - remove EH edges. */ - if (maybe_clean_or_replace_eh_stmt (old_stmt, stmt)) - bitmap_set_bit (need_eh_cleanup, bb->index); - - /* If we turned a not noreturn call into a noreturn one - schedule it for fixup. */ - if (!was_noreturn - && is_gimple_call (stmt) - && gimple_call_noreturn_p (stmt)) - stmts_to_fixup.safe_push (stmt); - - if (gimple_assign_single_p (stmt)) - { - tree rhs = gimple_assign_rhs1 (stmt); - if (TREE_CODE (rhs) == ADDR_EXPR) - recompute_tree_invariant_for_addr_expr (rhs); - } - } - } - - /* Visit BB successor PHI nodes and replace PHI args. */ - FOR_EACH_EDGE (e, ei, bb->succs) - { - for (gphi_iterator gpi = gsi_start_phis (e->dest); - !gsi_end_p (gpi); gsi_next (&gpi)) - { - gphi *phi = gpi.phi (); - use_operand_p use_p = PHI_ARG_DEF_PTR_FROM_EDGE (phi, e); - tree arg = USE_FROM_PTR (use_p); - if (TREE_CODE (arg) != SSA_NAME - || virtual_operand_p (arg)) - continue; - tree val = op_with_constant_singleton_value_range (arg); - if (val && may_propagate_copy (arg, val)) - propagate_value (use_p, val); - } - } - - bb->flags |= BB_VISITED; - - return taken_edge; -} - -/* Restore/pop VRs valid only for BB when we leave BB. */ - -void -evrp_dom_walker::after_dom_children (basic_block bb ATTRIBUTE_UNUSED) -{ - gcc_checking_assert (!stack.is_empty ()); - while (stack.last ().first != NULL_TREE) - pop_value_range (stack.last ().first); - stack.pop (); -} - -/* Push the Value Range of VAR to the stack and update it with new VR. */ - -void -evrp_dom_walker::push_value_range (tree var, value_range *vr) -{ - if (SSA_NAME_VERSION (var) >= num_vr_values) - return; - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "pushing new range for "); - print_generic_expr (dump_file, var); - fprintf (dump_file, ": "); - dump_value_range (dump_file, vr); - fprintf (dump_file, "\n"); - } - stack.safe_push (std::make_pair (var, get_value_range (var))); - vr_value[SSA_NAME_VERSION (var)] = vr; -} - -/* Pop the Value Range from the vrp_stack and update VAR with it. */ - -value_range * -evrp_dom_walker::pop_value_range (tree var) -{ - value_range *vr = stack.last ().second; - gcc_checking_assert (var == stack.last ().first); - if (dump_file && (dump_flags & TDF_DETAILS)) - { - fprintf (dump_file, "popping range for "); - print_generic_expr (dump_file, var); - fprintf (dump_file, ", restoring "); - dump_value_range (dump_file, vr); - fprintf (dump_file, "\n"); - } - vr_value[SSA_NAME_VERSION (var)] = vr; - stack.pop (); - return vr; -} - - -/* Main entry point for the early vrp pass which is a simplified non-iterative - version of vrp where basic blocks are visited in dominance order. Value - ranges discovered in early vrp will also be used by ipa-vrp. */ - -static unsigned int -execute_early_vrp () -{ - edge e; - edge_iterator ei; - basic_block bb; - - loop_optimizer_init (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS); - rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); - scev_initialize (); - calculate_dominance_info (CDI_DOMINATORS); - FOR_EACH_BB_FN (bb, cfun) - { - bb->flags &= ~BB_VISITED; - FOR_EACH_EDGE (e, ei, bb->preds) - e->flags |= EDGE_EXECUTABLE; - } - vrp_initialize_lattice (); - - /* Walk stmts in dominance order and propagate VRP. */ - evrp_dom_walker walker; - walker.walk (ENTRY_BLOCK_PTR_FOR_FN (cfun)); - - if (dump_file) - { - fprintf (dump_file, "\nValue ranges after Early VRP:\n\n"); - dump_all_value_ranges (dump_file); - fprintf (dump_file, "\n"); - } - - /* Remove stmts in reverse order to make debug stmt creation possible. */ - while (! walker.stmts_to_remove.is_empty ()) - { - gimple *stmt = walker.stmts_to_remove.pop (); - if (dump_file && dump_flags & TDF_DETAILS) - { - fprintf (dump_file, "Removing dead stmt "); - print_gimple_stmt (dump_file, stmt, 0); - fprintf (dump_file, "\n"); - } - gimple_stmt_iterator gsi = gsi_for_stmt (stmt); - if (gimple_code (stmt) == GIMPLE_PHI) - remove_phi_node (&gsi, true); - else - { - unlink_stmt_vdef (stmt); - gsi_remove (&gsi, true); - release_defs (stmt); - } - } - - if (!bitmap_empty_p (walker.need_eh_cleanup)) - gimple_purge_all_dead_eh_edges (walker.need_eh_cleanup); - - /* Fixup stmts that became noreturn calls. This may require splitting - blocks and thus isn't possible during the dominator walk. Do this - in reverse order so we don't inadvertedly remove a stmt we want to - fixup by visiting a dominating now noreturn call first. */ - while (!walker.stmts_to_fixup.is_empty ()) - { - gimple *stmt = walker.stmts_to_fixup.pop (); - fixup_noreturn_call (stmt); - } - - vrp_free_lattice (); - scev_finalize (); - loop_optimizer_finalize (); - return 0; -} - - /* Main entry point to VRP (Value Range Propagation). This pass is loosely based on J. R. C. Patterson, ``Accurate Static Branch Prediction by Value Range Propagation,'' in SIGPLAN Conference on @@ -11470,15 +6844,14 @@ execute_vrp (bool warn_array_bounds_p) /* For visiting PHI nodes we need EDGE_DFS_BACK computed. */ mark_dfs_back_edges (); - vrp_initialize_lattice (); - vrp_initialize (); class vrp_prop vrp_prop; + vrp_prop.vrp_initialize (); vrp_prop.ssa_propagate (); - vrp_finalize (warn_array_bounds_p); + vrp_prop.vrp_finalize (warn_array_bounds_p); /* We must identify jump threading opportunities before we release the datastructures built by VRP. */ - identify_jump_threads (); + identify_jump_threads (&vrp_prop.vr_values); /* A comparison of an SSA_NAME against a constant where the SSA_NAME was set by a type conversion can often be rewritten to use the @@ -11492,11 +6865,9 @@ execute_vrp (bool warn_array_bounds_p) { gimple *last = last_stmt (bb); if (last && gimple_code (last) == GIMPLE_COND) - simplify_cond_using_ranges_2 (as_a <gcond *> (last)); + vrp_prop.vr_values.simplify_cond_using_ranges_2 (as_a <gcond *> (last)); } - vrp_free_lattice (); - free_numbers_of_iterations_estimates (cfun); /* ASSERT_EXPRs must be removed before finalizing jump threads @@ -11599,44 +6970,3 @@ make_pass_vrp (gcc::context *ctxt) { return new pass_vrp (ctxt); } - -namespace { - -const pass_data pass_data_early_vrp = -{ - GIMPLE_PASS, /* type */ - "evrp", /* name */ - OPTGROUP_NONE, /* optinfo_flags */ - TV_TREE_EARLY_VRP, /* tv_id */ - PROP_ssa, /* properties_required */ - 0, /* properties_provided */ - 0, /* properties_destroyed */ - 0, /* todo_flags_start */ - ( TODO_cleanup_cfg | TODO_update_ssa | TODO_verify_all ), -}; - -class pass_early_vrp : public gimple_opt_pass -{ -public: - pass_early_vrp (gcc::context *ctxt) - : gimple_opt_pass (pass_data_early_vrp, ctxt) - {} - - /* opt_pass methods: */ - opt_pass * clone () { return new pass_early_vrp (m_ctxt); } - virtual bool gate (function *) - { - return flag_tree_vrp != 0; - } - virtual unsigned int execute (function *) - { return execute_early_vrp (); } - -}; // class pass_vrp -} // anon namespace - -gimple_opt_pass * -make_pass_early_vrp (gcc::context *ctxt) -{ - return new pass_early_vrp (ctxt); -} - |