-// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
use std::num::wrapping::OverflowingOps;
use std::cmp::Ordering;
use std::collections::hash_map::Entry::Vacant;
-use std::{i8, i16, i32, i64};
+use std::{i8, i16, i32, i64, u8, u16, u32, u64};
use std::rc::Rc;
fn lookup_const<'a>(tcx: &'a ty::ctxt, e: &Expr) -> Option<&'a Expr> {
Ok(const_uint((!a).wrapping_add(1)))
}
+fn const_uint_not(a: u64, opt_ety: Option<UintTy>) -> const_val {
+ let mask = match opt_ety {
+ Some(UintTy::U8) => u8::MAX as u64,
+ Some(UintTy::U16) => u16::MAX as u64,
+ Some(UintTy::U32) => u32::MAX as u64,
+ None | Some(UintTy::U64) => u64::MAX,
+ };
+ const_uint(!a & mask)
+}
+
macro_rules! overflow_checking_body {
($a:ident, $b:ident, $ety:ident, $overflowing_op:ident,
lhs: $to_8_lhs:ident $to_16_lhs:ident $to_32_lhs:ident,
ast::ExprUnary(ast::UnNot, ref inner) => {
match try!(eval_const_expr_partial(tcx, &**inner, ety)) {
const_int(i) => const_int(!i),
- const_uint(i) => const_uint(!i),
+ const_uint(i) => const_uint_not(i, expr_uint_type),
const_bool(b) => const_bool(!b),
const_str(_) => signal!(e, NotOnString),
const_float(_) => signal!(e, NotOnFloat),
--- /dev/null
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+const U8_MAX_HALF: u8 = !0u8 / 2;
+const U16_MAX_HALF: u16 = !0u16 / 2;
+const U32_MAX_HALF: u32 = !0u32 / 2;
+const U64_MAX_HALF: u64 = !0u64 / 2;
+
+fn main() {
+ assert_eq!(U8_MAX_HALF, 0x7f);
+ assert_eq!(U16_MAX_HALF, 0x7fff);
+ assert_eq!(U32_MAX_HALF, 0x7fff_ffff);
+ assert_eq!(U64_MAX_HALF, 0x7fff_ffff_ffff_ffff);
+}