diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc index 3b397ae2941dc2f714831f2b162eca59f855d64a..7d2352dbcddfc8dd4d725ab7cc49b38842712de0 100644 --- a/gcc/fold-const.cc +++ b/gcc/fold-const.cc @@ -150,6 +150,50 @@ static tree fold_convert_const (enum tree_code, tree, tree); static tree fold_view_convert_expr (tree, tree); static tree fold_negate_expr (location_t, tree); +/* This is a helper function to detect min/max for some operands of COND_EXPR. + The form is "(EXP0 CMP EXP1) ? EXP2 : EXP3". */ +tree_code +minmax_from_comparison (tree_code cmp, tree exp0, tree exp1, tree exp2, tree exp3) +{ + enum tree_code code = ERROR_MARK; + + if (HONOR_NANS (exp0) || HONOR_SIGNED_ZEROS (exp0)) + return ERROR_MARK; + + if (!operand_equal_p (exp0, exp2)) + return ERROR_MARK; + + if (TREE_CODE (exp3) == INTEGER_CST && TREE_CODE (exp1) == INTEGER_CST) + { + if (wi::to_widest (exp1) == (wi::to_widest (exp3) - 1)) + { + /* X <= Y - 1 equals to X < Y. */ + if (cmp == LE_EXPR) + code = LT_EXPR; + /* X > Y - 1 equals to X >= Y. */ + if (cmp == GT_EXPR) + code = GE_EXPR; + } + if (wi::to_widest (exp1) == (wi::to_widest (exp3) + 1)) + { + /* X < Y + 1 equals to X <= Y. */ + if (cmp == LT_EXPR) + code = LE_EXPR; + /* X >= Y + 1 equals to X > Y. */ + if (cmp == GE_EXPR) + code = GT_EXPR; + } + } + if (code != ERROR_MARK + || operand_equal_p (exp1, exp3)) + { + if (cmp == LT_EXPR || cmp == LE_EXPR) + code = MIN_EXPR; + if (cmp == GT_EXPR || cmp == GE_EXPR) + code = MAX_EXPR; + } + return code; +} /* Return EXPR_LOCATION of T if it is not UNKNOWN_LOCATION. Otherwise, return LOC. */ diff --git a/gcc/fold-const.h b/gcc/fold-const.h index 56ecaa87fc6d60e5525ff517e6ba852f9e8477a4..b828badc42f5bc9a5e79ed260eda6e6810cb8d86 100644 --- a/gcc/fold-const.h +++ b/gcc/fold-const.h @@ -246,6 +246,9 @@ extern tree fold_build_pointer_plus_hwi_loc (location_t loc, tree ptr, HOST_WIDE #define fold_build_pointer_plus_hwi(p,o) \ fold_build_pointer_plus_hwi_loc (UNKNOWN_LOCATION, p, o) +extern tree_code minmax_from_comparison (tree_code, tree, tree, + tree, tree); + /* In gimple-fold.cc. */ extern void clear_type_padding_in_mask (tree, unsigned char *); extern bool clear_padding_type_may_have_padding_p (tree); diff --git a/gcc/match.pd b/gcc/match.pd index c4320781f5b85e9e31702067991b596c98deb5f4..fad337a96972f10dce5f4d17b102fa6544f12ef7 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -4677,34 +4677,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) || TYPE_SIGN (c2_type) == TYPE_SIGN (from_type))))) { if (cmp != EQ_EXPR) - { - if (wi::to_widest (@3) == (wi::to_widest (@2) - 1)) - { - /* X <= Y - 1 equals to X < Y. */ - if (cmp == LE_EXPR) - code = LT_EXPR; - /* X > Y - 1 equals to X >= Y. */ - if (cmp == GT_EXPR) - code = GE_EXPR; - } - if (wi::to_widest (@3) == (wi::to_widest (@2) + 1)) - { - /* X < Y + 1 equals to X <= Y. */ - if (cmp == LT_EXPR) - code = LE_EXPR; - /* X >= Y + 1 equals to X > Y. */ - if (cmp == GE_EXPR) - code = GT_EXPR; - } - if (code != ERROR_MARK - || wi::to_widest (@2) == wi::to_widest (@3)) - { - if (cmp == LT_EXPR || cmp == LE_EXPR) - code = MIN_EXPR; - if (cmp == GT_EXPR || cmp == GE_EXPR) - code = MAX_EXPR; - } - } + code = minmax_from_comparison (cmp, @1, @3, @1, @2); /* Can do A == C1 ? A : C2 -> A == C1 ? C1 : C2? */ else if (int_fits_type_p (@3, from_type)) code = EQ_EXPR;