diff options
| -rw-r--r-- | gcc/expr.cc | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/gcc/expr.cc b/gcc/expr.cc index 56b5187..6027e7f 100644 --- a/gcc/expr.cc +++ b/gcc/expr.cc @@ -13162,16 +13162,31 @@ do_store_flag (sepops ops, rtx target, machine_mode mode) && integer_zerop (arg1) && (TYPE_PRECISION (ops->type) != 1 || TYPE_UNSIGNED (ops->type))) { - gimple *srcstmt = get_def_for_expr (arg0, BIT_AND_EXPR); - if (srcstmt - && integer_pow2p (gimple_assign_rhs2 (srcstmt))) + wide_int nz = tree_nonzero_bits (arg0); + + if (wi::popcount (nz) == 1) { + tree op0; + int bitnum; + gimple *srcstmt = get_def_for_expr (arg0, BIT_AND_EXPR); + /* If the defining statement was (x & POW2), then remove the and + as we are going to add it back. */ + if (srcstmt + && integer_pow2p (gimple_assign_rhs2 (srcstmt))) + { + op0 = gimple_assign_rhs1 (srcstmt); + bitnum = tree_log2 (gimple_assign_rhs2 (srcstmt)); + } + else + { + op0 = arg0; + bitnum = wi::exact_log2 (nz); + } enum tree_code tcode = code == NE ? NE_EXPR : EQ_EXPR; - int bitnum = tree_log2 (gimple_assign_rhs2 (srcstmt)); type = lang_hooks.types.type_for_mode (mode, unsignedp); return expand_single_bit_test (loc, tcode, - gimple_assign_rhs1 (srcstmt), + op0, bitnum, type, target, mode); } } |