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Auto merge of #109517 - matthiaskrgr:rollup-m3orqzd, r=matthiaskrgr

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Rollup of 7 pull requests

Successful merges:

 - #108541 (Suppress `opaque_hidden_inferred_bound` for nested RPITs)
 - #109137 (resolve: Querify most cstore access methods (subset 2))
 - #109380 (add `known-bug` test for unsoundness issue)
 - #109462 (Make alias-eq have a relation direction (and rename it to alias-relate))
 - #109475 (Simpler checked shifts in MIR building)
 - #109504 (Stabilize `arc_into_inner` and `rc_into_inner`.)
 - #109506 (make param bound vars visibly bound vars with -Zverbose)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
This commit is contained in:
bors 2023-03-23 12:35:05 +00:00
commit 99c49d95cd
54 changed files with 729 additions and 245 deletions
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56
compiler/rustc_mir_build/src/build/expr/as_rvalue.rs
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@ -566,41 +566,51 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
Rvalue::Use(Operand::Move(val))
}
BinOp::Shl | BinOp::Shr if self.check_overflow && ty.is_integral() => {
// Consider that the shift overflows if `rhs < 0` or `rhs >= bits`.
// This can be encoded as a single operation as `(rhs & -bits) != 0`.
let (size, _) = ty.int_size_and_signed(self.tcx);
let bits = size.bits();
debug_assert!(bits.is_power_of_two());
let mask = !((bits - 1) as u128);
// For an unsigned RHS, the shift is in-range for `rhs < bits`.
// For a signed RHS, `IntToInt` cast to the equivalent unsigned
// type and do that same comparison. Because the type is the
// same size, there's no negative shift amount that ends up
// overlapping with valid ones, thus it catches negatives too.
let (lhs_size, _) = ty.int_size_and_signed(self.tcx);
let rhs_ty = rhs.ty(&self.local_decls, self.tcx);
let (rhs_size, _) = rhs_ty.int_size_and_signed(self.tcx);
let mask = Operand::const_from_scalar(
let (unsigned_rhs, unsigned_ty) = match rhs_ty.kind() {
ty::Uint(_) => (rhs.to_copy(), rhs_ty),
ty::Int(int_width) => {
let uint_ty = self.tcx.mk_mach_uint(int_width.to_unsigned());
let rhs_temp = self.temp(uint_ty, span);
self.cfg.push_assign(
block,
source_info,
rhs_temp,
Rvalue::Cast(CastKind::IntToInt, rhs.to_copy(), uint_ty),
);
(Operand::Move(rhs_temp), uint_ty)
}
_ => unreachable!("only integers are shiftable"),
};
// This can't overflow because the largest shiftable types are 128-bit,
// which fits in `u8`, the smallest possible `unsigned_ty`.
// (And `from_uint` will `bug!` if that's ever no longer true.)
let lhs_bits = Operand::const_from_scalar(
self.tcx,
rhs_ty,
Scalar::from_uint(rhs_size.truncate(mask), rhs_size),
unsigned_ty,
Scalar::from_uint(lhs_size.bits(), rhs_size),
span,
);
let outer_bits = self.temp(rhs_ty, span);
let inbounds = self.temp(bool_ty, span);
self.cfg.push_assign(
block,
source_info,
outer_bits,
Rvalue::BinaryOp(BinOp::BitAnd, Box::new((rhs.to_copy(), mask))),
);
let overflows = self.temp(bool_ty, span);
let zero = self.zero_literal(span, rhs_ty);
self.cfg.push_assign(
block,
source_info,
overflows,
Rvalue::BinaryOp(BinOp::Ne, Box::new((Operand::Move(outer_bits), zero))),
inbounds,
Rvalue::BinaryOp(BinOp::Lt, Box::new((unsigned_rhs, lhs_bits))),
);
let overflow_err = AssertKind::Overflow(op, lhs.to_copy(), rhs.to_copy());
block = self.assert(block, Operand::Move(overflows), false, overflow_err, span);
block = self.assert(block, Operand::Move(inbounds), true, overflow_err, span);
Rvalue::BinaryOp(op, Box::new((lhs, rhs)))
}
BinOp::Div | BinOp::Rem if ty.is_integral() => {