| /* Header file for range operator class. |
| Copyright (C) 2017-2024 Free Software Foundation, Inc. |
| Contributed by Andrew MacLeod <amacleod@redhat.com> |
| and Aldy Hernandez <aldyh@redhat.com>. |
| |
| This file is part of GCC. |
| |
| GCC is free software; you can redistribute it and/or modify it under |
| the terms of the GNU General Public License as published by the Free |
| Software Foundation; either version 3, or (at your option) any later |
| version. |
| |
| GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
| WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GCC; see the file COPYING3. If not see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #ifndef GCC_RANGE_OP_H |
| #define GCC_RANGE_OP_H |
| |
| // This class is implemented for each kind of operator supported by |
| // the range generator. It serves various purposes. |
| // |
| // 1 - Generates range information for the specific operation between |
| // two ranges. This provides the ability to fold ranges for an |
| // expression. |
| // |
| // 2 - Performs range algebra on the expression such that a range can be |
| // adjusted in terms of one of the operands: |
| // |
| // def = op1 + op2 |
| // |
| // Given a range for def, we can adjust the range so that it is in |
| // terms of either operand. |
| // |
| // op1_range (def_range, op2) will adjust the range in place so it |
| // is in terms of op1. Since op1 = def - op2, it will subtract |
| // op2 from each element of the range. |
| // |
| // 3 - Creates a range for an operand based on whether the result is 0 or |
| // non-zero. This is mostly for logical true false, but can serve other |
| // purposes. |
| // ie 0 = op1 - op2 implies op2 has the same range as op1. |
| // |
| // 4 - All supported range combinations are explicitly specified. |
| // Any desired combinations should be implemented for each operator. |
| // When new range classes are added, new matching prototypes should be |
| // added. |
| |
| class range_operator |
| { |
| friend class range_op_table; |
| public: |
| // Perform an operation between 2 ranges and return it. |
| virtual bool fold_range (irange &r, tree type, |
| const irange &lh, |
| const irange &rh, |
| relation_trio = TRIO_VARYING) const; |
| virtual bool fold_range (frange &r, tree type, |
| const frange &lh, |
| const frange &rh, |
| relation_trio = TRIO_VARYING) const; |
| virtual bool fold_range (irange &r, tree type, |
| const frange &lh, |
| const irange &rh, |
| relation_trio = TRIO_VARYING) const; |
| virtual bool fold_range (irange &r, tree type, |
| const frange &lh, |
| const frange &rh, |
| relation_trio = TRIO_VARYING) const; |
| virtual bool fold_range (frange &r, tree type, |
| const irange &lh, |
| const irange &rh, |
| relation_trio = TRIO_VARYING) const; |
| |
| // Return the range for op[12] in the general case. LHS is the range for |
| // the LHS of the expression, OP[12]is the range for the other |
| // |
| // The operand and the result is returned in R. |
| // |
| // TYPE is the expected type of the range. |
| // |
| // Return TRUE if the operation is performed and a valid range is available. |
| // |
| // i.e. [LHS] = ??? + OP2 |
| // is re-formed as R = [LHS] - OP2. |
| virtual bool op1_range (irange &r, tree type, |
| const irange &lhs, |
| const irange &op2, |
| relation_trio = TRIO_VARYING) const; |
| virtual bool op1_range (frange &r, tree type, |
| const frange &lhs, |
| const frange &op2, |
| relation_trio = TRIO_VARYING) const; |
| virtual bool op1_range (frange &r, tree type, |
| const irange &lhs, |
| const frange &op2, |
| relation_trio = TRIO_VARYING) const; |
| |
| |
| virtual bool op2_range (irange &r, tree type, |
| const irange &lhs, |
| const irange &op1, |
| relation_trio = TRIO_VARYING) const; |
| virtual bool op2_range (frange &r, tree type, |
| const frange &lhs, |
| const frange &op1, |
| relation_trio = TRIO_VARYING) const; |
| virtual bool op2_range (frange &r, tree type, |
| const irange &lhs, |
| const frange &op1, |
| relation_trio = TRIO_VARYING) const; |
| |
| // The following routines are used to represent relations between the |
| // various operations. If the caller knows where the symbolics are, |
| // it can query for relationships between them given known ranges. |
| // the optional relation passed in is the relation between op1 and op2. |
| virtual relation_kind lhs_op1_relation (const irange &lhs, |
| const irange &op1, |
| const irange &op2, |
| relation_kind = VREL_VARYING) const; |
| virtual relation_kind lhs_op1_relation (const frange &lhs, |
| const frange &op1, |
| const frange &op2, |
| relation_kind = VREL_VARYING) const; |
| virtual relation_kind lhs_op1_relation (const irange &lhs, |
| const frange &op1, |
| const frange &op2, |
| relation_kind = VREL_VARYING) const; |
| |
| virtual relation_kind lhs_op2_relation (const irange &lhs, |
| const irange &op1, |
| const irange &op2, |
| relation_kind = VREL_VARYING) const; |
| virtual relation_kind lhs_op2_relation (const frange &lhs, |
| const frange &op1, |
| const frange &op2, |
| relation_kind = VREL_VARYING) const; |
| virtual relation_kind lhs_op2_relation (const irange &lhs, |
| const frange &op1, |
| const frange &op2, |
| relation_kind = VREL_VARYING) const; |
| |
| virtual relation_kind op1_op2_relation (const irange &lhs, |
| const irange &op1, |
| const irange &op2) const; |
| virtual relation_kind op1_op2_relation (const irange &lhs, |
| const frange &op1, |
| const frange &op2) const; |
| virtual relation_kind op1_op2_relation (const frange &lhs, |
| const frange &op1, |
| const frange &op2) const; |
| |
| virtual bool overflow_free_p (const irange &lh, const irange &rh, |
| relation_trio = TRIO_VARYING) const; |
| |
| // Compatability check for operands. |
| virtual bool operand_check_p (tree, tree, tree) const; |
| |
| protected: |
| // Perform an integral operation between 2 sub-ranges and return it. |
| virtual void wi_fold (irange &r, tree type, |
| const wide_int &lh_lb, |
| const wide_int &lh_ub, |
| const wide_int &rh_lb, |
| const wide_int &rh_ub) const; |
| // Effect of relation for generic fold_range clients. |
| virtual bool op1_op2_relation_effect (irange &lhs_range, tree type, |
| const irange &op1_range, |
| const irange &op2_range, |
| relation_kind rel) const; |
| // Called by fold range to split small subranges into parts. |
| void wi_fold_in_parts (irange &r, tree type, |
| const wide_int &lh_lb, |
| const wide_int &lh_ub, |
| const wide_int &rh_lb, |
| const wide_int &rh_ub) const; |
| |
| // Called by fold range to split small subranges into parts when op1 == op2 |
| void wi_fold_in_parts_equiv (irange &r, tree type, |
| const wide_int &lb, |
| const wide_int &ub, |
| unsigned limit) const; |
| // Apply any bitmasks implied by these ranges. |
| virtual void update_bitmask (irange &, const irange &, const irange &) const; |
| |
| // Perform an float operation between 2 ranges and return it. |
| virtual void rv_fold (frange &r, tree type, |
| const REAL_VALUE_TYPE &lh_lb, |
| const REAL_VALUE_TYPE &lh_ub, |
| const REAL_VALUE_TYPE &rh_lb, |
| const REAL_VALUE_TYPE &rh_ub, |
| relation_kind) const; |
| }; |
| |
| class range_op_handler |
| { |
| public: |
| range_op_handler (); |
| range_op_handler (unsigned); |
| operator bool () const; |
| range_operator *range_op () const; |
| |
| bool fold_range (vrange &r, tree type, |
| const vrange &lh, |
| const vrange &rh, |
| relation_trio = TRIO_VARYING) const; |
| bool op1_range (vrange &r, tree type, |
| const vrange &lhs, |
| const vrange &op2, |
| relation_trio = TRIO_VARYING) const; |
| bool op2_range (vrange &r, tree type, |
| const vrange &lhs, |
| const vrange &op1, |
| relation_trio = TRIO_VARYING) const; |
| relation_kind lhs_op1_relation (const vrange &lhs, |
| const vrange &op1, |
| const vrange &op2, |
| relation_kind = VREL_VARYING) const; |
| relation_kind lhs_op2_relation (const vrange &lhs, |
| const vrange &op1, |
| const vrange &op2, |
| relation_kind = VREL_VARYING) const; |
| relation_kind op1_op2_relation (const vrange &lhs, |
| const vrange &op1, |
| const vrange &op2) const; |
| bool overflow_free_p (const vrange &lh, const vrange &rh, |
| relation_trio = TRIO_VARYING) const; |
| bool operand_check_p (tree, tree, tree) const; |
| protected: |
| unsigned dispatch_kind (const vrange &lhs, const vrange &op1, |
| const vrange& op2) const; |
| range_operator *m_operator; |
| }; |
| |
| // Cast the range in R to TYPE if R supports TYPE. |
| |
| inline bool |
| range_cast (vrange &r, tree type) |
| { |
| gcc_checking_assert (r.supports_type_p (type)); |
| Value_Range tmp (r); |
| Value_Range varying (type); |
| varying.set_varying (type); |
| // Call op_convert, if it fails, the result is varying. |
| if (!range_op_handler (CONVERT_EXPR).fold_range (r, type, tmp, varying)) |
| { |
| r.set_varying (type); |
| return false; |
| } |
| return true; |
| } |
| |
| // Range cast which is capable of switching range kinds. |
| // ie for float to int. |
| |
| inline bool |
| range_cast (Value_Range &r, tree type) |
| { |
| Value_Range tmp (r); |
| Value_Range varying (type); |
| varying.set_varying (type); |
| |
| // Ensure we are in the correct mode for the call to fold. |
| r.set_type (type); |
| |
| // Call op_convert, if it fails, the result is varying. |
| if (!range_op_handler (CONVERT_EXPR).fold_range (r, type, tmp, varying)) |
| { |
| r.set_varying (type); |
| return false; |
| } |
| return true; |
| } |
| |
| |
| extern void wi_set_zero_nonzero_bits (tree type, |
| const wide_int &, const wide_int &, |
| wide_int &maybe_nonzero, |
| wide_int &mustbe_nonzero); |
| |
| // These are extra operators that do not fit in the normal scheme of things. |
| // Add them to the end of the tree-code vector, and provide a name for |
| // each allowing for easy access when required. |
| |
| #define OP_WIDEN_MULT_SIGNED ((unsigned) MAX_TREE_CODES) |
| #define OP_WIDEN_MULT_UNSIGNED ((unsigned) MAX_TREE_CODES + 1) |
| #define OP_WIDEN_PLUS_SIGNED ((unsigned) MAX_TREE_CODES + 2) |
| #define OP_WIDEN_PLUS_UNSIGNED ((unsigned) MAX_TREE_CODES + 3) |
| #define RANGE_OP_TABLE_SIZE ((unsigned) MAX_TREE_CODES + 4) |
| |
| // This implements the range operator tables as local objects. |
| |
| class range_op_table |
| { |
| public: |
| range_op_table (); |
| inline range_operator *operator[] (unsigned code) |
| { |
| gcc_checking_assert (code < RANGE_OP_TABLE_SIZE); |
| return m_range_tree[code]; |
| } |
| protected: |
| inline void set (unsigned code, range_operator &op) |
| { |
| gcc_checking_assert (code < RANGE_OP_TABLE_SIZE); |
| gcc_checking_assert (m_range_tree[code] == NULL); |
| m_range_tree[code] = &op; |
| } |
| range_operator *m_range_tree[RANGE_OP_TABLE_SIZE]; |
| void initialize_integral_ops (); |
| void initialize_pointer_ops (); |
| void initialize_float_ops (); |
| }; |
| #endif // GCC_RANGE_OP_H |
