/* Match-and-simplify patterns for shared GENERIC and GIMPLE folding. This file is consumed by genmatch which produces gimple-match.c and generic-match.c from it. Copyright (C) 2014 Free Software Foundation, Inc. Contributed by Richard Biener and Prathamesh Kulkarni 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 . */ /* Generic tree predicates we inherit. */ (define_predicates integer_onep integer_zerop integer_all_onesp integer_minus_onep integer_each_onep real_zerop real_onep real_minus_onep CONSTANT_CLASS_P tree_expr_nonnegative_p) /* Operator lists. */ (define_operator_list tcc_comparison lt le eq ne ge gt unordered ordered unlt unle ungt unge uneq ltgt) (define_operator_list inverted_tcc_comparison ge gt ne eq lt le ordered unordered ge gt le lt ltgt uneq) (define_operator_list inverted_tcc_comparison_with_nans unge ungt ne eq unlt unle ordered unordered ge gt le lt ltgt uneq) /* Simplifications of operations with one constant operand and simplifications to constants or single values. */ (for op (plus pointer_plus minus bit_ior bit_xor) (simplify (op @0 integer_zerop) (non_lvalue @0))) /* 0 +p index -> (type)index */ (simplify (pointer_plus integer_zerop @1) (non_lvalue (convert @1))) /* See if ARG1 is zero and X + ARG1 reduces to X. Likewise if the operands are reversed. */ (simplify (plus:c @0 real_zerop@1) (if (fold_real_zero_addition_p (type, @1, 0)) (non_lvalue @0))) /* See if ARG1 is zero and X - ARG1 reduces to X. */ (simplify (minus @0 real_zerop@1) (if (fold_real_zero_addition_p (type, @1, 1)) (non_lvalue @0))) /* Simplify x - x. This is unsafe for certain floats even in non-IEEE formats. In IEEE, it is unsafe because it does wrong for NaNs. Also note that operand_equal_p is always false if an operand is volatile. */ (simplify (minus @0 @0) (if (!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type))) { build_zero_cst (type); })) (simplify (mult @0 integer_zerop@1) @1) /* Maybe fold x * 0 to 0. The expressions aren't the same when x is NaN, since x * 0 is also NaN. Nor are they the same in modes with signed zeros, since multiplying a negative value by 0 gives -0, not +0. */ (simplify (mult @0 real_zerop@1) (if (!HONOR_NANS (TYPE_MODE (type)) && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))) @1)) /* In IEEE floating point, x*1 is not equivalent to x for snans. Likewise for complex arithmetic with signed zeros. */ (simplify (mult @0 real_onep) (if (!HONOR_SNANS (TYPE_MODE (type)) && (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)) || !COMPLEX_FLOAT_TYPE_P (type))) (non_lvalue @0))) /* Transform x * -1.0 into -x. */ (simplify (mult @0 real_minus_onep) (if (!HONOR_SNANS (TYPE_MODE (type)) && (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)) || !COMPLEX_FLOAT_TYPE_P (type))) (negate @0))) /* Make sure to preserve divisions by zero. This is the reason why we don't simplify x / x to 1 or 0 / x to 0. */ (for op (mult trunc_div ceil_div floor_div round_div exact_div) (simplify (op @0 integer_onep) (non_lvalue @0))) /* X / -1 is -X. */ (for div (trunc_div ceil_div floor_div round_div exact_div) (simplify (div @0 INTEGER_CST@1) (if (!TYPE_UNSIGNED (type) && wi::eq_p (@1, -1)) (negate @0)))) /* For unsigned integral types, FLOOR_DIV_EXPR is the same as TRUNC_DIV_EXPR. Rewrite into the latter in this case. */ (simplify (floor_div @0 @1) (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type)) (trunc_div @0 @1))) /* Optimize A / A to 1.0 if we don't care about NaNs or Infinities. Skip the transformation for non-real operands. */ (simplify (rdiv @0 @0) (if (SCALAR_FLOAT_TYPE_P (type) && ! HONOR_NANS (TYPE_MODE (type)) && ! HONOR_INFINITIES (TYPE_MODE (type))) { build_real (type, dconst1); }) /* The complex version of the above A / A optimization. */ (if (COMPLEX_FLOAT_TYPE_P (type) && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (type))) && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (type)))) { build_complex (type, build_real (TREE_TYPE (type), dconst1), build_real (TREE_TYPE (type), dconst0)); })) /* In IEEE floating point, x/1 is not equivalent to x for snans. */ (simplify (rdiv @0 real_onep) (if (!HONOR_SNANS (TYPE_MODE (type))) (non_lvalue @0))) /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */ (simplify (rdiv @0 real_minus_onep) (if (!HONOR_SNANS (TYPE_MODE (type))) (negate @0))) /* If ARG1 is a constant, we can convert this to a multiply by the reciprocal. This does not have the same rounding properties, so only do this if -freciprocal-math. We can actually always safely do it if ARG1 is a power of two, but it's hard to tell if it is or not in a portable manner. */ (for cst (REAL_CST COMPLEX_CST VECTOR_CST) (simplify (rdiv @0 cst@1) (if (optimize) (if (flag_reciprocal_math) (with { tree tem = fold_binary (RDIV_EXPR, type, build_one_cst (type), @1); } (if (tem) (mult @0 { tem; } )))) (if (cst != COMPLEX_CST) (with { tree inverse = exact_inverse (type, @1); } (if (inverse) (mult @0 { inverse; } ))))))) /* Same applies to modulo operations, but fold is inconsistent here and simplifies 0 % x to 0, only preserving literal 0 % 0. */ (for mod (ceil_mod floor_mod round_mod trunc_mod) /* 0 % X is always zero. */ (simplify (mod integer_zerop@0 @1) /* But not for 0 % 0 so that we can get the proper warnings and errors. */ (if (!integer_zerop (@1)) @0)) /* X % 1 is always zero. */ (simplify (mod @0 integer_onep) { build_zero_cst (type); }) /* X % -1 is zero. */ (simplify (mod @0 INTEGER_CST@1) (if (!TYPE_UNSIGNED (type) && wi::eq_p (@1, -1)) { build_zero_cst (type); }))) /* X % -C is the same as X % C. */ (simplify (trunc_mod @0 INTEGER_CST@1) (if (TYPE_SIGN (type) == SIGNED && !TREE_OVERFLOW (@1) && wi::neg_p (@1) && !TYPE_OVERFLOW_TRAPS (type) /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */ && !sign_bit_p (@1, @1)) (trunc_mod @0 (negate @1)))) /* x | ~0 -> ~0 */ (simplify (bit_ior @0 integer_all_onesp@1) @1) /* x & 0 -> 0 */ (simplify (bit_and @0 integer_zerop@1) @1) /* x ^ x -> 0 */ (simplify (bit_xor @0 @0) { build_zero_cst (type); }) /* Canonicalize X ^ ~0 to ~X. */ (simplify (bit_xor @0 integer_all_onesp@1) (bit_not @0)) /* x & ~0 -> x */ (simplify (bit_and @0 integer_all_onesp) (non_lvalue @0)) /* x & x -> x, x | x -> x */ (for bitop (bit_and bit_ior) (simplify (bitop @0 @0) (non_lvalue @0))) (simplify (abs (negate @0)) (abs @0)) (simplify (abs tree_expr_nonnegative_p@0) @0) /* Try to fold (type) X op CST -> (type) (X op ((type-x) CST)) when profitable. For bitwise binary operations apply operand conversions to the binary operation result instead of to the operands. This allows to combine successive conversions and bitwise binary operations. We combine the above two cases by using a conditional convert. */ (for bitop (bit_and bit_ior bit_xor) (simplify (bitop (convert @0) (convert? @1)) (if (((TREE_CODE (@1) == INTEGER_CST && INTEGRAL_TYPE_P (TREE_TYPE (@0)) && int_fits_type_p (@1, TREE_TYPE (@0))) || (GIMPLE && types_compatible_p (TREE_TYPE (@0), TREE_TYPE (@1))) || (GENERIC && TREE_TYPE (@0) == TREE_TYPE (@1))) /* ??? This transform conflicts with fold-const.c doing Convert (T)(x & c) into (T)x & (T)c, if c is an integer constants (if x has signed type, the sign bit cannot be set in c). This folds extension into the BIT_AND_EXPR. Restrict it to GIMPLE to avoid endless recursions. */ && (bitop != BIT_AND_EXPR || GIMPLE) && (/* That's a good idea if the conversion widens the operand, thus after hoisting the conversion the operation will be narrower. */ TYPE_PRECISION (TREE_TYPE (@0)) < TYPE_PRECISION (type) /* It's also a good idea if the conversion is to a non-integer mode. */ || GET_MODE_CLASS (TYPE_MODE (type)) != MODE_INT /* Or if the precision of TO is not the same as the precision of its mode. */ || TYPE_PRECISION (type) != GET_MODE_PRECISION (TYPE_MODE (type)))) (convert (bitop @0 (convert @1)))))) /* Simplify (A & B) OP0 (C & B) to (A OP0 C) & B. */ (for bitop (bit_and bit_ior bit_xor) (simplify (bitop (bit_and:c @0 @1) (bit_and @2 @1)) (bit_and (bitop @0 @2) @1))) /* (x | CST1) & CST2 -> (x & CST2) | (CST1 & CST2) */ (simplify (bit_and (bit_ior @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2) (bit_ior (bit_and @0 @2) (bit_and @1 @2))) /* Combine successive equal operations with constants. */ (for bitop (bit_and bit_ior bit_xor) (simplify (bitop (bitop @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2) (bitop @0 (bitop @1 @2)))) /* Try simple folding for X op !X, and X op X with the help of the truth_valued_p and logical_inverted_value predicates. */ (match truth_valued_p @0 (if (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1))) (for op (tcc_comparison truth_and truth_andif truth_or truth_orif truth_xor) (match truth_valued_p (op @0 @1))) (match truth_valued_p (truth_not @0)) (match (logical_inverted_value @0) (bit_not truth_valued_p@0)) (match (logical_inverted_value @0) (eq @0 integer_zerop) (if (INTEGRAL_TYPE_P (TREE_TYPE (@0))))) (match (logical_inverted_value @0) (ne truth_valued_p@0 integer_onep) (if (INTEGRAL_TYPE_P (TREE_TYPE (@0))))) (match (logical_inverted_value @0) (bit_xor truth_valued_p@0 integer_onep) (if (INTEGRAL_TYPE_P (TREE_TYPE (@0))))) /* X & !X -> 0. */ (simplify (bit_and:c @0 (logical_inverted_value @0)) { build_zero_cst (type); }) /* X | !X and X ^ !X -> 1, , if X is truth-valued. */ (for op (bit_ior bit_xor) (simplify (op:c truth_valued_p@0 (logical_inverted_value @0)) { constant_boolean_node (true, type); })) (for bitop (bit_and bit_ior) rbitop (bit_ior bit_and) /* (x | y) & x -> x */ /* (x & y) | x -> x */ (simplify (bitop:c (rbitop:c @0 @1) @0) @0) /* (~x | y) & x -> x & y */ /* (~x & y) | x -> x | y */ (simplify (bitop:c (rbitop:c (bit_not @0) @1) @0) (bitop @0 @1))) /* If arg1 and arg2 are booleans (or any single bit type) then try to simplify: (~X & Y) -> X < Y (X & ~Y) -> Y < X (~X | Y) -> X <= Y (X | ~Y) -> Y <= X But only do this if our result feeds into a comparison as this transformation is not always a win, particularly on targets with and-not instructions. -> simplify_bitwise_binary_boolean */ (simplify (ne (bit_and:c (bit_not @0) @1) integer_zerop) (if (INTEGRAL_TYPE_P (TREE_TYPE (@1)) && TYPE_PRECISION (TREE_TYPE (@1)) == 1) (lt @0 @1))) (simplify (ne (bit_ior:c (bit_not @0) @1) integer_zerop) (if (INTEGRAL_TYPE_P (TREE_TYPE (@1)) && TYPE_PRECISION (TREE_TYPE (@1)) == 1) (le @0 @1))) /* ~~x -> x */ (simplify (bit_not (bit_not @0)) @0) /* Associate (p +p off1) +p off2 as (p +p (off1 + off2)). */ (simplify (pointer_plus (pointer_plus @0 @1) @3) (pointer_plus @0 (plus @1 @3))) /* Pattern match tem1 = (long) ptr1; tem2 = (long) ptr2; tem3 = tem2 - tem1; tem4 = (unsigned long) tem3; tem5 = ptr1 + tem4; and produce tem5 = ptr2; */ (simplify (pointer_plus @0 (convert?@2 (minus@3 (convert @1) (convert @0)))) /* Conditionally look through a sign-changing conversion. */ (if (TYPE_PRECISION (TREE_TYPE (@2)) == TYPE_PRECISION (TREE_TYPE (@3)) && ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@1))) || (GENERIC && type == TREE_TYPE (@1)))) @1)) /* Pattern match tem = (sizetype) ptr; tem = tem & algn; tem = -tem; ... = ptr p+ tem; and produce the simpler and easier to analyze with respect to alignment ... = ptr & ~algn; */ (simplify (pointer_plus @0 (negate (bit_and (convert @0) INTEGER_CST@1))) (with { tree algn = wide_int_to_tree (TREE_TYPE (@0), wi::bit_not (@1)); } (bit_and @0 { algn; }))) /* We can't reassociate at all for saturating types. */ (if (!TYPE_SATURATING (type)) /* Contract negates. */ /* A + (-B) -> A - B */ (simplify (plus:c (convert1? @0) (convert2? (negate @1))) /* Apply STRIP_NOPS on @0 and the negate. */ (if (tree_nop_conversion_p (type, TREE_TYPE (@0)) && tree_nop_conversion_p (type, TREE_TYPE (@1)) && !TYPE_OVERFLOW_SANITIZED (type)) (minus (convert @0) (convert @1)))) /* A - (-B) -> A + B */ (simplify (minus (convert1? @0) (convert2? (negate @1))) (if (tree_nop_conversion_p (type, TREE_TYPE (@0)) && tree_nop_conversion_p (type, TREE_TYPE (@1)) && !TYPE_OVERFLOW_SANITIZED (type)) (plus (convert @0) (convert @1)))) /* -(-A) -> A */ (simplify (negate (convert? (negate @1))) (if (tree_nop_conversion_p (type, TREE_TYPE (@1)) && !TYPE_OVERFLOW_SANITIZED (type)) (convert @1))) /* We can't reassociate floating-point or fixed-point plus or minus because of saturation to +-Inf. */ (if (!FLOAT_TYPE_P (type) && !FIXED_POINT_TYPE_P (type)) /* Match patterns that allow contracting a plus-minus pair irrespective of overflow issues. */ /* (A +- B) - A -> +- B */ /* (A +- B) -+ B -> A */ /* A - (A +- B) -> -+ B */ /* A +- (B -+ A) -> +- B */ (simplify (minus (plus:c @0 @1) @0) @1) (simplify (minus (minus @0 @1) @0) (negate @1)) (simplify (plus:c (minus @0 @1) @1) @0) (simplify (minus @0 (plus:c @0 @1)) (negate @1)) (simplify (minus @0 (minus @0 @1)) @1) /* (A +- CST) +- CST -> A + CST */ (for outer_op (plus minus) (for inner_op (plus minus) (simplify (outer_op (inner_op @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2) /* If the constant operation overflows we cannot do the transform as we would introduce undefined overflow, for example with (a - 1) + INT_MIN. */ (with { tree cst = fold_binary (outer_op == inner_op ? PLUS_EXPR : MINUS_EXPR, type, @1, @2); } (if (cst && !TREE_OVERFLOW (cst)) (inner_op @0 { cst; } )))))) /* (CST - A) +- CST -> CST - A */ (for outer_op (plus minus) (simplify (outer_op (minus CONSTANT_CLASS_P@1 @0) CONSTANT_CLASS_P@2) (with { tree cst = fold_binary (outer_op, type, @1, @2); } (if (cst && !TREE_OVERFLOW (cst)) (minus { cst; } @0))))) /* ~A + A -> -1 */ (simplify (plus:c (bit_not @0) @0) (if (!TYPE_OVERFLOW_TRAPS (type)) { build_all_ones_cst (type); })) /* ~A + 1 -> -A */ (simplify (plus (bit_not @0) integer_each_onep) (negate @0)) /* (T)(P + A) - (T)P -> (T) A */ (for add (plus pointer_plus) (simplify (minus (convert (add @0 @1)) (convert @0)) (if (TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (@1)) /* For integer types, if A has a smaller type than T the result depends on the possible overflow in P + A. E.g. T=size_t, A=(unsigned)429497295, P>0. However, if an overflow in P + A would cause undefined behavior, we can assume that there is no overflow. */ || (INTEGRAL_TYPE_P (TREE_TYPE (@0)) && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))) /* For pointer types, if the conversion of A to the final type requires a sign- or zero-extension, then we have to punt - it is not defined which one is correct. */ || (POINTER_TYPE_P (TREE_TYPE (@0)) && TREE_CODE (@1) == INTEGER_CST && tree_int_cst_sign_bit (@1) == 0)) (convert @1)))))) /* Simplifications of MIN_EXPR and MAX_EXPR. */ (for minmax (min max) (simplify (minmax @0 @0) @0)) (simplify (min @0 @1) (if (INTEGRAL_TYPE_P (type) && TYPE_MIN_VALUE (type) && operand_equal_p (@1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST)) @1)) (simplify (max @0 @1) (if (INTEGRAL_TYPE_P (type) && TYPE_MAX_VALUE (type) && operand_equal_p (@1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST)) @1)) /* Simplifications of shift and rotates. */ (for rotate (lrotate rrotate) (simplify (rotate integer_all_onesp@0 @1) @0)) /* Optimize -1 >> x for arithmetic right shifts. */ (simplify (rshift integer_all_onesp@0 @1) (if (!TYPE_UNSIGNED (type) && tree_expr_nonnegative_p (@1)) @0)) (for shiftrotate (lrotate rrotate lshift rshift) (simplify (shiftrotate @0 integer_zerop) (non_lvalue @0)) (simplify (shiftrotate integer_zerop@0 @1) @0) /* Prefer vector1 << scalar to vector1 << vector2 if vector2 is uniform. */ (for vec (VECTOR_CST CONSTRUCTOR) (simplify (shiftrotate @0 vec@1) (with { tree tem = uniform_vector_p (@1); } (if (tem) (shiftrotate @0 { tem; })))))) /* Rewrite an LROTATE_EXPR by a constant into an RROTATE_EXPR by a new constant. */ (simplify (lrotate @0 INTEGER_CST@1) (rrotate @0 { fold_binary (MINUS_EXPR, TREE_TYPE (@1), build_int_cst (TREE_TYPE (@1), element_precision (type)), @1); })) /* Simplifications of conversions. */ /* Basic strip-useless-type-conversions / strip_nops. */ (for cvt (convert view_convert float fix_trunc) (simplify (cvt @0) (if ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@0))) || (GENERIC && type == TREE_TYPE (@0))) @0))) /* Contract view-conversions. */ (simplify (view_convert (view_convert @0)) (view_convert @0)) /* For integral conversions with the same precision or pointer conversions use a NOP_EXPR instead. */ (simplify (view_convert @0) (if ((INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type)) && (INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0))) && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (@0))) (convert @0))) /* Strip inner integral conversions that do not change precision or size. */ (simplify (view_convert (convert@0 @1)) (if ((INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0))) && (INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1))) && (TYPE_PRECISION (TREE_TYPE (@0)) == TYPE_PRECISION (TREE_TYPE (@1))) && (TYPE_SIZE (TREE_TYPE (@0)) == TYPE_SIZE (TREE_TYPE (@1)))) (view_convert @1))) /* Re-association barriers around constants and other re-association barriers can be removed. */ (simplify (paren CONSTANT_CLASS_P@0) @0) (simplify (paren (paren@1 @0)) @1) /* Handle cases of two conversions in a row. */ (for ocvt (convert float fix_trunc) (for icvt (convert float) (simplify (ocvt (icvt@1 @0)) (with { tree inside_type = TREE_TYPE (@0); tree inter_type = TREE_TYPE (@1); int inside_int = INTEGRAL_TYPE_P (inside_type); int inside_ptr = POINTER_TYPE_P (inside_type); int inside_float = FLOAT_TYPE_P (inside_type); int inside_vec = TREE_CODE (inside_type) == VECTOR_TYPE; unsigned int inside_prec = TYPE_PRECISION (inside_type); int inside_unsignedp = TYPE_UNSIGNED (inside_type); int inter_int = INTEGRAL_TYPE_P (inter_type); int inter_ptr = POINTER_TYPE_P (inter_type); int inter_float = FLOAT_TYPE_P (inter_type); int inter_vec = TREE_CODE (inter_type) == VECTOR_TYPE; unsigned int inter_prec = TYPE_PRECISION (inter_type); int inter_unsignedp = TYPE_UNSIGNED (inter_type); int final_int = INTEGRAL_TYPE_P (type); int final_ptr = POINTER_TYPE_P (type); int final_float = FLOAT_TYPE_P (type); int final_vec = TREE_CODE (type) == VECTOR_TYPE; unsigned int final_prec = TYPE_PRECISION (type); int final_unsignedp = TYPE_UNSIGNED (type); } /* In addition to the cases of two conversions in a row handled below, if we are converting something to its own type via an object of identical or wider precision, neither conversion is needed. */ (if (((GIMPLE && useless_type_conversion_p (type, inside_type)) || (GENERIC && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (inside_type))) && (((inter_int || inter_ptr) && final_int) || (inter_float && final_float)) && inter_prec >= final_prec) (ocvt @0)) /* Likewise, if the intermediate and initial types are either both float or both integer, we don't need the middle conversion if the former is wider than the latter and doesn't change the signedness (for integers). Avoid this if the final type is a pointer since then we sometimes need the middle conversion. Likewise if the final type has a precision not equal to the size of its mode. */ (if (((inter_int && inside_int) || (inter_float && inside_float) || (inter_vec && inside_vec)) && inter_prec >= inside_prec && (inter_float || inter_vec || inter_unsignedp == inside_unsignedp) && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type)) && TYPE_MODE (type) == TYPE_MODE (inter_type)) && ! final_ptr && (! final_vec || inter_prec == inside_prec)) (ocvt @0)) /* If we have a sign-extension of a zero-extended value, we can replace that by a single zero-extension. Likewise if the final conversion does not change precision we can drop the intermediate conversion. */ (if (inside_int && inter_int && final_int && ((inside_prec < inter_prec && inter_prec < final_prec && inside_unsignedp && !inter_unsignedp) || final_prec == inter_prec)) (ocvt @0)) /* Two conversions in a row are not needed unless: - some conversion is floating-point (overstrict for now), or - some conversion is a vector (overstrict for now), or - the intermediate type is narrower than both initial and final, or - the intermediate type and innermost type differ in signedness, and the outermost type is wider than the intermediate, or - the initial type is a pointer type and the precisions of the intermediate and final types differ, or - the final type is a pointer type and the precisions of the initial and intermediate types differ. */ (if (! inside_float && ! inter_float && ! final_float && ! inside_vec && ! inter_vec && ! final_vec && (inter_prec >= inside_prec || inter_prec >= final_prec) && ! (inside_int && inter_int && inter_unsignedp != inside_unsignedp && inter_prec < final_prec) && ((inter_unsignedp && inter_prec > inside_prec) == (final_unsignedp && final_prec > inter_prec)) && ! (inside_ptr && inter_prec != final_prec) && ! (final_ptr && inside_prec != inter_prec) && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type)) && TYPE_MODE (type) == TYPE_MODE (inter_type))) (ocvt @0)) /* A truncation to an unsigned type (a zero-extension) should be canonicalized as bitwise and of a mask. */ (if (final_int && inter_int && inside_int && final_prec == inside_prec && final_prec > inter_prec && inter_unsignedp) (convert (bit_and @0 { wide_int_to_tree (inside_type, wi::mask (inter_prec, false, TYPE_PRECISION (inside_type))); }))) /* If we are converting an integer to a floating-point that can represent it exactly and back to an integer, we can skip the floating-point conversion. */ (if (inside_int && inter_float && final_int && (unsigned) significand_size (TYPE_MODE (inter_type)) >= inside_prec - !inside_unsignedp) (convert @0)))))) /* If we have a narrowing conversion to an integral type that is fed by a BIT_AND_EXPR, we might be able to remove the BIT_AND_EXPR if it merely masks off bits outside the final type (and nothing else). */ (simplify (convert (bit_and @0 INTEGER_CST@1)) (if (INTEGRAL_TYPE_P (type) && INTEGRAL_TYPE_P (TREE_TYPE (@0)) && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (@0)) && operand_equal_p (@1, build_low_bits_mask (TREE_TYPE (@1), TYPE_PRECISION (type)), 0)) (convert @0))) /* (X /[ex] A) * A -> X. */ (simplify (mult (convert? (exact_div @0 @1)) @1) /* Look through a sign-changing conversion. */ (if (TYPE_PRECISION (TREE_TYPE (@0)) == TYPE_PRECISION (type)) (convert @0))) /* Canonicalization of binary operations. */ /* Convert X + -C into X - C. */ (simplify (plus @0 REAL_CST@1) (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1))) (with { tree tem = fold_unary (NEGATE_EXPR, type, @1); } (if (!TREE_OVERFLOW (tem) || !flag_trapping_math) (minus @0 { tem; }))))) /* Convert x+x into x*2.0. */ (simplify (plus @0 @0) (if (SCALAR_FLOAT_TYPE_P (type)) (mult @0 { build_real (type, dconst2); }))) (simplify (minus integer_zerop @1) (negate @1)) /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether ARG0 is zero and X + ARG0 reduces to X, since that would mean (-ARG1 + ARG0) reduces to -ARG1. */ (simplify (minus real_zerop@0 @1) (if (fold_real_zero_addition_p (type, @0, 0)) (negate @1))) /* Transform x * -1 into -x. */ (simplify (mult @0 integer_minus_onep) (negate @0)) /* COMPLEX_EXPR and REALPART/IMAGPART_EXPR cancellations. */ (simplify (complex (realpart @0) (imagpart @0)) @0) (simplify (realpart (complex @0 @1)) @0) (simplify (imagpart (complex @0 @1)) @1) /* BSWAP simplifications, transforms checked by gcc.dg/builtin-bswap-8.c. */ (for bswap (BUILT_IN_BSWAP16 BUILT_IN_BSWAP32 BUILT_IN_BSWAP64) (simplify (bswap (bswap @0)) @0) (simplify (bswap (bit_not (bswap @0))) (bit_not @0)) (for bitop (bit_xor bit_ior bit_and) (simplify (bswap (bitop:c (bswap @0) @1)) (bitop @0 (bswap @1))))) /* Combine COND_EXPRs and VEC_COND_EXPRs. */ /* Simplify constant conditions. Only optimize constant conditions when the selected branch has the same type as the COND_EXPR. This avoids optimizing away "c ? x : throw", where the throw has a void type. Note that we cannot throw away the fold-const.c variant nor this one as we depend on doing this transform before possibly A ? B : B -> B triggers and the fold-const.c one can optimize 0 ? A : B to B even if A has side-effects. Something genmatch cannot handle. */ (simplify (cond INTEGER_CST@0 @1 @2) (if (integer_zerop (@0) && (!VOID_TYPE_P (TREE_TYPE (@2)) || VOID_TYPE_P (type))) @2) (if (!integer_zerop (@0) && (!VOID_TYPE_P (TREE_TYPE (@1)) || VOID_TYPE_P (type))) @1)) (simplify (vec_cond VECTOR_CST@0 @1 @2) (if (integer_all_onesp (@0)) @1) (if (integer_zerop (@0)) @2)) (for cnd (cond vec_cond) /* A ? B : (A ? X : C) -> A ? B : C. */ (simplify (cnd @0 (cnd @0 @1 @2) @3) (cnd @0 @1 @3)) (simplify (cnd @0 @1 (cnd @0 @2 @3)) (cnd @0 @1 @3)) /* A ? B : B -> B. */ (simplify (cnd @0 @1 @1) @1)) /* !A ? B : C -> A ? C : B. */ (simplify (cond (logical_inverted_value truth_valued_p@0) @1 @2) (cond @0 @2 @1)) /* Simplifications of comparisons. */ /* We can simplify a logical negation of a comparison to the inverted comparison. As we cannot compute an expression operator using invert_tree_comparison we have to simulate that with expression code iteration. */ (for cmp (tcc_comparison) icmp (inverted_tcc_comparison) ncmp (inverted_tcc_comparison_with_nans) /* Ideally we'd like to combine the following two patterns and handle some more cases by using (logical_inverted_value (cmp @0 @1)) here but for that genmatch would need to "inline" that. For now implement what forward_propagate_comparison did. */ (simplify (bit_not (cmp @0 @1)) (if (VECTOR_TYPE_P (type) || (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1)) /* Comparison inversion may be impossible for trapping math, invert_tree_comparison will tell us. But we can't use a computed operator in the replacement tree thus we have to play the trick below. */ (with { enum tree_code ic = invert_tree_comparison (cmp, HONOR_NANS (TYPE_MODE (TREE_TYPE (@0)))); } (if (ic == icmp) (icmp @0 @1)) (if (ic == ncmp) (ncmp @0 @1))))) (simplify (bit_xor (cmp @0 @1) integer_onep) (if (INTEGRAL_TYPE_P (type)) (with { enum tree_code ic = invert_tree_comparison (cmp, HONOR_NANS (TYPE_MODE (TREE_TYPE (@0)))); } (if (ic == icmp) (icmp @0 @1)) (if (ic == ncmp) (ncmp @0 @1))))))