The code in fold_single_bit_test, checks if
the inner was a right shift and improve the bitnum
based on that. But since the inner will always be a
SSA_NAME at this point, the code is dead. Move it over
to use the helper function get_def_for_expr instead.
OK? Bootstrapped and tested on x86_64-linux.
gcc/ChangeLog:
* expr.cc (fold_single_bit_test): Use get_def_for_expr
instead of checking the inner's code.
---
gcc/expr.cc | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/gcc/expr.cc b/gcc/expr.cc
index 6221b6991c5..a61772b6808 100644
--- a/gcc/expr.cc
+++ b/gcc/expr.cc
@@ -12920,6 +12920,7 @@ fold_single_bit_test (location_t loc, enum tree_code
code,
int ops_unsigned;
tree signed_type, unsigned_type, intermediate_type;
tree one;
+ gimple *inner_def;
/* First, see if we can fold the single bit test into a sign-bit
test. */
@@ -12939,14 +12940,14 @@ fold_single_bit_test (location_t loc, enum tree_code
code,
/* If INNER is a right shift of a constant and it plus BITNUM does
not overflow, adjust BITNUM and INNER. */
- if (TREE_CODE (inner) == RSHIFT_EXPR
- && TREE_CODE (TREE_OPERAND (inner, 1)) == INTEGER_CST
+ if ((inner_def = get_def_for_expr (inner, RSHIFT_EXPR))
+ && TREE_CODE (gimple_assign_rhs2 (inner_def)) == INTEGER_CST
&& bitnum < TYPE_PRECISION (type)
- && wi::ltu_p (wi::to_wide (TREE_OPERAND (inner, 1)),
+ && wi::ltu_p (wi::to_wide (gimple_assign_rhs2 (inner_def)),
TYPE_PRECISION (type) - bitnum))
{
- bitnum += tree_to_uhwi (TREE_OPERAND (inner, 1));
- inner = TREE_OPERAND (inner, 0);
+ bitnum += tree_to_uhwi (gimple_assign_rhs2 (inner_def));
+ inner = gimple_assign_rhs1 (inner_def);
}
/* If we are going to be able to omit the AND below, we must do our
--
2.17.1
