diff options
author | Richard Guenther <rguenther@suse.de> | 2011-07-11 14:27:04 +0000 |
---|---|---|
committer | Richard Biener <rguenth@gcc.gnu.org> | 2011-07-11 14:27:04 +0000 |
commit | dcc95c20883bb4f104314650e76176d30ad8396e (patch) | |
tree | bafcbf8cbeddfaf7f813f266159b82dd6a444b62 /gcc/tree-vrp.c | |
parent | f07e929dd8f68f5328cb6f4ec46e6d8897447a7a (diff) | |
download | gcc-dcc95c20883bb4f104314650e76176d30ad8396e.zip gcc-dcc95c20883bb4f104314650e76176d30ad8396e.tar.gz gcc-dcc95c20883bb4f104314650e76176d30ad8396e.tar.bz2 |
tree-vrp.c (simplify_conversion_using_ranges): Manually translate the source value-range through the conversion chain.
2011-07-11 Richard Guenther <rguenther@suse.de>
* tree-vrp.c (simplify_conversion_using_ranges): Manually
translate the source value-range through the conversion chain.
From-SVN: r176154
Diffstat (limited to 'gcc/tree-vrp.c')
-rw-r--r-- | gcc/tree-vrp.c | 61 |
1 files changed, 43 insertions, 18 deletions
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c index 68998b37..c975a5d 100644 --- a/gcc/tree-vrp.c +++ b/gcc/tree-vrp.c @@ -7347,30 +7347,55 @@ simplify_switch_using_ranges (gimple stmt) static bool simplify_conversion_using_ranges (gimple stmt) { - tree rhs1 = gimple_assign_rhs1 (stmt); - gimple def_stmt = SSA_NAME_DEF_STMT (rhs1); - value_range_t *final, *inner; - - /* Obtain final and inner value-ranges for a conversion - sequence (final-type)(intermediate-type)inner-type. */ - final = get_value_range (gimple_assign_lhs (stmt)); - if (final->type != VR_RANGE) - return false; + tree innerop, middleop, finaltype; + gimple def_stmt; + value_range_t *innervr; + double_int innermin, innermax, middlemin, middlemax; + + finaltype = TREE_TYPE (gimple_assign_lhs (stmt)); + 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; - rhs1 = gimple_assign_rhs1 (def_stmt); - if (TREE_CODE (rhs1) != SSA_NAME) + innerop = gimple_assign_rhs1 (def_stmt); + if (TREE_CODE (innerop) != SSA_NAME) return false; - inner = get_value_range (rhs1); - if (inner->type != VR_RANGE) + + /* Get the value-range of the inner operand. */ + innervr = get_value_range (innerop); + if (innervr->type != VR_RANGE + || TREE_CODE (innervr->min) != INTEGER_CST + || TREE_CODE (innervr->max) != INTEGER_CST) return false; - /* If the value-range is preserved by the conversion sequence strip - the intermediate conversion. */ - if (!tree_int_cst_equal (final->min, inner->min) - || !tree_int_cst_equal (final->max, inner->max)) + + /* Simulate the conversion chain to check if the result is equal if + the middle conversion is removed. */ + innermin = tree_to_double_int (innervr->min); + innermax = tree_to_double_int (innervr->max); + middlemin = double_int_ext (innermin, TYPE_PRECISION (TREE_TYPE (middleop)), + TYPE_UNSIGNED (TREE_TYPE (middleop))); + middlemax = double_int_ext (innermax, TYPE_PRECISION (TREE_TYPE (middleop)), + TYPE_UNSIGNED (TREE_TYPE (middleop))); + /* If the middle values do not represent a proper range fail. */ + if (double_int_cmp (middlemin, middlemax, + TYPE_UNSIGNED (TREE_TYPE (middleop))) > 0) return false; - gimple_assign_set_rhs1 (stmt, rhs1); + if (!double_int_equal_p (double_int_ext (middlemin, + TYPE_PRECISION (finaltype), + TYPE_UNSIGNED (finaltype)), + double_int_ext (innermin, + TYPE_PRECISION (finaltype), + TYPE_UNSIGNED (finaltype))) + || !double_int_equal_p (double_int_ext (middlemax, + TYPE_PRECISION (finaltype), + TYPE_UNSIGNED (finaltype)), + double_int_ext (innermax, + TYPE_PRECISION (finaltype), + TYPE_UNSIGNED (finaltype)))) + return false; + + gimple_assign_set_rhs1 (stmt, innerop); update_stmt (stmt); return true; } |