bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-ty/src/mir/eval.rs')
-rw-r--r--crates/hir-ty/src/mir/eval.rs41
1 files changed, 23 insertions, 18 deletions
diff --git a/crates/hir-ty/src/mir/eval.rs b/crates/hir-ty/src/mir/eval.rs
index 9811cd9192..7ff68774bc 100644
--- a/crates/hir-ty/src/mir/eval.rs
+++ b/crates/hir-ty/src/mir/eval.rs
@@ -860,6 +860,16 @@ impl Evaluator<'_> {
let is_signed = matches!(ty.as_builtin(), Some(BuiltinType::Int(_)));
let l128 = i128::from_le_bytes(pad16(lc, is_signed));
let r128 = i128::from_le_bytes(pad16(rc, is_signed));
+ let check_overflow = |r: i128| {
+ // FIXME: this is not very correct, and only catches the basic cases.
+ let r = r.to_le_bytes();
+ for &k in &r[lc.len()..] {
+ if k != 0 && (k != 255 || !is_signed) {
+ return Err(MirEvalError::Panic(format!("Overflow in {op:?}")));
+ }
+ }
+ Ok(Owned(r[0..lc.len()].into()))
+ };
match op {
BinOp::Ge | BinOp::Gt | BinOp::Le | BinOp::Lt | BinOp::Eq | BinOp::Ne => {
let r = op.run_compare(l128, r128) as u8;
@@ -888,28 +898,23 @@ impl Evaluator<'_> {
BinOp::BitXor => l128 ^ r128,
_ => unreachable!(),
};
- let r = r.to_le_bytes();
- for &k in &r[lc.len()..] {
- if k != 0 && (k != 255 || !is_signed) {
- return Err(MirEvalError::Panic(format!("Overflow in {op:?}")));
- }
- }
- Owned(r[0..lc.len()].into())
+ check_overflow(r)?
}
BinOp::Shl | BinOp::Shr => {
- let shift_amount = if r128 < 0 {
- return Err(MirEvalError::Panic(format!("Overflow in {op:?}")));
- } else if r128 > 128 {
+ let r = 'b: {
+ if let Ok(shift_amount) = u32::try_from(r128) {
+ let r = match op {
+ BinOp::Shl => l128.checked_shl(shift_amount),
+ BinOp::Shr => l128.checked_shr(shift_amount),
+ _ => unreachable!(),
+ };
+ if let Some(r) = r {
+ break 'b r;
+ }
+ };
return Err(MirEvalError::Panic(format!("Overflow in {op:?}")));
- } else {
- r128 as u8
- };
- let r = match op {
- BinOp::Shl => l128 << shift_amount,
- BinOp::Shr => l128 >> shift_amount,
- _ => unreachable!(),
};
- Owned(r.to_le_bytes()[0..lc.len()].into())
+ check_overflow(r)?
}
BinOp::Offset => not_supported!("offset binop"),
}