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Implement checked Shl/Shr at MIR building.

This commit is contained in:
Camille GILLOT 2023-02-13 21:08:15 +00:00
parent 43ee4d15bf
commit dd582bd7db
7 changed files with 109 additions and 107 deletions

View file

@ -59,22 +59,13 @@ impl<'tcx> fmt::Display for Discr<'tcx> {
}
}
fn int_size_and_signed<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> (Size, bool) {
let (int, signed) = match *ty.kind() {
ty::Int(ity) => (Integer::from_int_ty(&tcx, ity), true),
ty::Uint(uty) => (Integer::from_uint_ty(&tcx, uty), false),
_ => bug!("non integer discriminant"),
};
(int.size(), signed)
}
impl<'tcx> Discr<'tcx> {
/// Adds `1` to the value and wraps around if the maximum for the type is reached.
pub fn wrap_incr(self, tcx: TyCtxt<'tcx>) -> Self {
self.checked_add(tcx, 1).0
}
pub fn checked_add(self, tcx: TyCtxt<'tcx>, n: u128) -> (Self, bool) {
let (size, signed) = int_size_and_signed(tcx, self.ty);
let (size, signed) = self.ty.int_size_and_signed(tcx);
let (val, oflo) = if signed {
let min = size.signed_int_min();
let max = size.signed_int_max();
@ -922,12 +913,21 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for OpaqueTypeExpander<'tcx> {
}
impl<'tcx> Ty<'tcx> {
pub fn int_size_and_signed(self, tcx: TyCtxt<'tcx>) -> (Size, bool) {
let (int, signed) = match *self.kind() {
ty::Int(ity) => (Integer::from_int_ty(&tcx, ity), true),
ty::Uint(uty) => (Integer::from_uint_ty(&tcx, uty), false),
_ => bug!("non integer discriminant"),
};
(int.size(), signed)
}
/// Returns the maximum value for the given numeric type (including `char`s)
/// or returns `None` if the type is not numeric.
pub fn numeric_max_val(self, tcx: TyCtxt<'tcx>) -> Option<ty::Const<'tcx>> {
let val = match self.kind() {
ty::Int(_) | ty::Uint(_) => {
let (size, signed) = int_size_and_signed(tcx, self);
let (size, signed) = self.int_size_and_signed(tcx);
let val =
if signed { size.signed_int_max() as u128 } else { size.unsigned_int_max() };
Some(val)
@ -948,7 +948,7 @@ impl<'tcx> Ty<'tcx> {
pub fn numeric_min_val(self, tcx: TyCtxt<'tcx>) -> Option<ty::Const<'tcx>> {
let val = match self.kind() {
ty::Int(_) | ty::Uint(_) => {
let (size, signed) = int_size_and_signed(tcx, self);
let (size, signed) = self.int_size_and_signed(tcx);
let val = if signed { size.truncate(size.signed_int_min() as u128) } else { 0 };
Some(val)
}