===================================================================
@@ -7422,7 +7422,7 @@ gnat_to_gnu (Node_Id gnat_node)
enum tree_code code = gnu_codes[kind];
bool ignore_lhs_overflow = false;
location_t saved_location = input_location;
- tree gnu_type;
+ tree gnu_type, gnu_max_shift = NULL_TREE;
/* Fix operations set up for boolean types in GNU_CODES above. */
if (Is_Modular_Integer_Type (Underlying_Type (Etype (gnat_node))))
@@ -7445,6 +7445,17 @@ gnat_to_gnu (Node_Id gnat_node)
gnu_rhs = gnat_to_gnu (Right_Opnd (gnat_node));
gnu_type = gnu_result_type = get_unpadded_type (Etype (gnat_node));
+ /* If this is a shift, take the count as unsigned since that is what
+ most machines do and will generate simpler adjustments below. */
+ if (IN (kind, N_Op_Shift))
+ {
+ tree gnu_count_type
+ = gnat_unsigned_type_for (get_base_type (TREE_TYPE (gnu_rhs)));
+ gnu_rhs = convert (gnu_count_type, gnu_rhs);
+ gnu_max_shift
+ = convert (TREE_TYPE (gnu_rhs), TYPE_SIZE (gnu_type));
+ }
+
/* Pending generic support for efficient vector logical operations in
GCC, convert vectors to their representative array type view and
fallthrough. */
@@ -7468,25 +7479,20 @@ gnat_to_gnu (Node_Id gnat_node)
/* If this is a shift whose count is not guaranteed to be correct,
we need to adjust the shift count. */
- if (IN (kind, N_Op_Shift) && !Shift_Count_OK (gnat_node))
- {
- tree gnu_count_type = get_base_type (TREE_TYPE (gnu_rhs));
- tree gnu_max_shift
- = convert (gnu_count_type, TYPE_SIZE (gnu_type));
-
- if (kind == N_Op_Rotate_Left || kind == N_Op_Rotate_Right)
- gnu_rhs = build_binary_op (TRUNC_MOD_EXPR, gnu_count_type,
- gnu_rhs, gnu_max_shift);
- else if (kind == N_Op_Shift_Right_Arithmetic)
- gnu_rhs
- = build_binary_op
- (MIN_EXPR, gnu_count_type,
- build_binary_op (MINUS_EXPR,
- gnu_count_type,
- gnu_max_shift,
- build_int_cst (gnu_count_type, 1)),
- gnu_rhs);
- }
+ if ((kind == N_Op_Rotate_Left || kind == N_Op_Rotate_Right)
+ && !Shift_Count_OK (gnat_node))
+ gnu_rhs = build_binary_op (TRUNC_MOD_EXPR, TREE_TYPE (gnu_rhs),
+ gnu_rhs, gnu_max_shift);
+ else if (kind == N_Op_Shift_Right_Arithmetic
+ && !Shift_Count_OK (gnat_node))
+ gnu_rhs
+ = build_binary_op (MIN_EXPR, TREE_TYPE (gnu_rhs),
+ build_binary_op (MINUS_EXPR,
+ TREE_TYPE (gnu_rhs),
+ gnu_max_shift,
+ build_int_cst
+ (TREE_TYPE (gnu_rhs), 1)),
+ gnu_rhs);
/* For right shifts, the type says what kind of shift to do,
so we may need to choose a different type. In this case,
@@ -7533,18 +7539,15 @@ gnat_to_gnu (Node_Id gnat_node)
/* If this is a logical shift with the shift count not verified,
we must return zero if it is too large. We cannot compensate
- above in this case. */
+ beforehand in this case. */
if ((kind == N_Op_Shift_Left || kind == N_Op_Shift_Right)
&& !Shift_Count_OK (gnat_node))
gnu_result
- = build_cond_expr
- (gnu_type,
- build_binary_op (GE_EXPR, boolean_type_node,
- gnu_rhs,
- convert (TREE_TYPE (gnu_rhs),
- TYPE_SIZE (gnu_type))),
- build_int_cst (gnu_type, 0),
- gnu_result);
+ = build_cond_expr (gnu_type,
+ build_binary_op (GE_EXPR, boolean_type_node,
+ gnu_rhs, gnu_max_shift),
+ build_int_cst (gnu_type, 0),
+ gnu_result);
}
break;