diff options
| -rw-r--r-- | compiler/rustc_const_eval/src/interpret/operand.rs | 64 | ||||
| -rw-r--r-- | compiler/rustc_const_eval/src/interpret/place.rs | 8 | ||||
| -rw-r--r-- | compiler/rustc_const_eval/src/interpret/projection.rs | 4 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/gvn.rs | 30 | ||||
| -rw-r--r-- | tests/coverage/closure_macro.cov-map | 8 | ||||
| -rw-r--r-- | tests/coverage/closure_macro_async.cov-map | 8 |
6 files changed, 76 insertions, 46 deletions
diff --git a/compiler/rustc_const_eval/src/interpret/operand.rs b/compiler/rustc_const_eval/src/interpret/operand.rs index 291664d556a..3b5af113e99 100644 --- a/compiler/rustc_const_eval/src/interpret/operand.rs +++ b/compiler/rustc_const_eval/src/interpret/operand.rs @@ -113,28 +113,47 @@ impl<Prov: Provenance> Immediate<Prov> { } /// Assert that this immediate is a valid value for the given ABI. - pub fn assert_matches_abi(self, abi: Abi, cx: &impl HasDataLayout) { + pub fn assert_matches_abi(self, abi: Abi, msg: &str, cx: &impl HasDataLayout) { match (self, abi) { (Immediate::Scalar(scalar), Abi::Scalar(s)) => { - assert_eq!(scalar.size(), s.size(cx)); + assert_eq!(scalar.size(), s.size(cx), "{msg}: scalar value has wrong size"); if !matches!(s.primitive(), abi::Pointer(..)) { // This is not a pointer, it should not carry provenance. - assert!(matches!(scalar, Scalar::Int(..))); + assert!( + matches!(scalar, Scalar::Int(..)), + "{msg}: scalar value should be an integer, but has provenance" + ); } } (Immediate::ScalarPair(a_val, b_val), Abi::ScalarPair(a, b)) => { - assert_eq!(a_val.size(), a.size(cx)); + assert_eq!( + a_val.size(), + a.size(cx), + "{msg}: first component of scalar pair has wrong size" + ); if !matches!(a.primitive(), abi::Pointer(..)) { - assert!(matches!(a_val, Scalar::Int(..))); + assert!( + matches!(a_val, Scalar::Int(..)), + "{msg}: first component of scalar pair should be an integer, but has provenance" + ); } - assert_eq!(b_val.size(), b.size(cx)); + assert_eq!( + b_val.size(), + b.size(cx), + "{msg}: second component of scalar pair has wrong size" + ); if !matches!(b.primitive(), abi::Pointer(..)) { - assert!(matches!(b_val, Scalar::Int(..))); + assert!( + matches!(b_val, Scalar::Int(..)), + "{msg}: second component of scalar pair should be an integer, but has provenance" + ); } } - (Immediate::Uninit, _) => {} + (Immediate::Uninit, _) => { + assert!(abi.is_sized(), "{msg}: unsized immediates are not a thing"); + } _ => { - bug!("value {self:?} does not match ABI {abi:?})",) + bug!("{msg}: value {self:?} does not match ABI {abi:?})",) } } } @@ -241,6 +260,7 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> { #[inline(always)] pub fn from_immediate(imm: Immediate<Prov>, layout: TyAndLayout<'tcx>) -> Self { + // Without a `cx` we cannot call `assert_matches_abi`. debug_assert!( match (imm, layout.abi) { (Immediate::Scalar(..), Abi::Scalar(..)) => true, @@ -261,7 +281,6 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> { #[inline] pub fn from_scalar_int(s: ScalarInt, layout: TyAndLayout<'tcx>) -> Self { - assert_eq!(s.size(), layout.size); Self::from_scalar(Scalar::from(s), layout) } @@ -334,7 +353,10 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> { /// given layout. // Not called `offset` to avoid confusion with the trait method. fn offset_(&self, offset: Size, layout: TyAndLayout<'tcx>, cx: &impl HasDataLayout) -> Self { - debug_assert!(layout.is_sized(), "unsized immediates are not a thing"); + // Verify that the input matches its type. + if cfg!(debug_assertions) { + self.assert_matches_abi(self.layout.abi, "invalid input to Immediate::offset", cx); + } // `ImmTy` have already been checked to be in-bounds, so we can just check directly if this // remains in-bounds. This cannot actually be violated since projections are type-checked // and bounds-checked. @@ -368,32 +390,14 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> { // the field covers the entire type _ if layout.size == self.layout.size => { assert_eq!(offset.bytes(), 0); - assert!( - match (self.layout.abi, layout.abi) { - (Abi::Scalar(l), Abi::Scalar(r)) => l.size(cx) == r.size(cx), - (Abi::ScalarPair(l1, l2), Abi::ScalarPair(r1, r2)) => - l1.size(cx) == r1.size(cx) && l2.size(cx) == r2.size(cx), - _ => false, - }, - "cannot project into {} immediate with equally-sized field {}\nouter ABI: {:#?}\nfield ABI: {:#?}", - self.layout.ty, - layout.ty, - self.layout.abi, - layout.abi, - ); **self } // extract fields from types with `ScalarPair` ABI (Immediate::ScalarPair(a_val, b_val), Abi::ScalarPair(a, b)) => { - assert_matches!(layout.abi, Abi::Scalar(..)); Immediate::from(if offset.bytes() == 0 { - // It is "okay" to transmute from `usize` to a pointer (GVN relies on that). - // So only compare the size. - assert_eq!(layout.size, a.size(cx)); a_val } else { assert_eq!(offset, a.size(cx).align_to(b.align(cx).abi)); - assert_eq!(layout.size, b.size(cx)); b_val }) } @@ -405,6 +409,8 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> { self.layout ), }; + // Ensure the new layout matches the new value. + inner_val.assert_matches_abi(layout.abi, "invalid field type in Immediate::offset", cx); ImmTy::from_immediate(inner_val, layout) } diff --git a/compiler/rustc_const_eval/src/interpret/place.rs b/compiler/rustc_const_eval/src/interpret/place.rs index 49656e10f2a..81b926a1b65 100644 --- a/compiler/rustc_const_eval/src/interpret/place.rs +++ b/compiler/rustc_const_eval/src/interpret/place.rs @@ -658,7 +658,11 @@ where // Things can ge wrong in quite weird ways when this is violated. // Unfortunately this is too expensive to do in release builds. if cfg!(debug_assertions) { - src.assert_matches_abi(local_layout.abi, self); + src.assert_matches_abi( + local_layout.abi, + "invalid immediate for given destination place", + self, + ); } } Left(mplace) => { @@ -679,7 +683,7 @@ where ) -> InterpResult<'tcx> { // We use the sizes from `value` below. // Ensure that matches the type of the place it is written to. - value.assert_matches_abi(layout.abi, self); + value.assert_matches_abi(layout.abi, "invalid immediate for given destination place", self); // Note that it is really important that the type here is the right one, and matches the // type things are read at. In case `value` is a `ScalarPair`, we don't do any magic here // to handle padding properly, which is only correct if we never look at this data with the diff --git a/compiler/rustc_const_eval/src/interpret/projection.rs b/compiler/rustc_const_eval/src/interpret/projection.rs index cc49d7cebf4..e636090a324 100644 --- a/compiler/rustc_const_eval/src/interpret/projection.rs +++ b/compiler/rustc_const_eval/src/interpret/projection.rs @@ -82,6 +82,10 @@ pub trait Projectable<'tcx, Prov: Provenance>: Sized + std::fmt::Debug { self.offset_with_meta(offset, OffsetMode::Inbounds, MemPlaceMeta::None, layout, ecx) } + /// This does an offset-by-zero, which is effectively a transmute. Note however that + /// not all transmutes are supported by all projectables -- specifically, if this is an + /// `OpTy` or `ImmTy`, the new layout must have almost the same ABI as the old one + /// (only changing the `valid_range` is allowed and turning integers into pointers). fn transmute<M: Machine<'tcx, Provenance = Prov>>( &self, layout: TyAndLayout<'tcx>, diff --git a/compiler/rustc_mir_transform/src/gvn.rs b/compiler/rustc_mir_transform/src/gvn.rs index 0bb46675e9a..daf868559bc 100644 --- a/compiler/rustc_mir_transform/src/gvn.rs +++ b/compiler/rustc_mir_transform/src/gvn.rs @@ -103,7 +103,7 @@ use rustc_middle::ty::layout::{HasParamEnv, LayoutOf}; use rustc_middle::ty::{self, Ty, TyCtxt}; use rustc_span::DUMMY_SP; use rustc_span::def_id::DefId; -use rustc_target::abi::{self, Abi, FIRST_VARIANT, FieldIdx, Size, VariantIdx}; +use rustc_target::abi::{self, Abi, FIRST_VARIANT, FieldIdx, Primitive, Size, VariantIdx}; use smallvec::SmallVec; use tracing::{debug, instrument, trace}; @@ -568,13 +568,29 @@ impl<'body, 'tcx> VnState<'body, 'tcx> { CastKind::Transmute => { let value = self.evaluated[value].as_ref()?; let to = self.ecx.layout_of(to).ok()?; - // `offset` for immediates only supports scalar/scalar-pair ABIs, - // so bail out if the target is not one. + // `offset` for immediates generally only supports projections that match the + // type of the immediate. However, as a HACK, we exploit that it can also do + // limited transmutes: it only works between types with the same layout, and + // cannot transmute pointers to integers. if value.as_mplace_or_imm().is_right() { - match (value.layout.abi, to.abi) { - (Abi::Scalar(..), Abi::Scalar(..)) => {} - (Abi::ScalarPair(..), Abi::ScalarPair(..)) => {} - _ => return None, + let can_transmute = match (value.layout.abi, to.abi) { + (Abi::Scalar(s1), Abi::Scalar(s2)) => { + s1.size(&self.ecx) == s2.size(&self.ecx) + && !matches!(s1.primitive(), Primitive::Pointer(..)) + } + (Abi::ScalarPair(a1, b1), Abi::ScalarPair(a2, b2)) => { + a1.size(&self.ecx) == a2.size(&self.ecx) && + b1.size(&self.ecx) == b2.size(&self.ecx) && + // The alignment of the second component determines its offset, so that also needs to match. + b1.align(&self.ecx) == b2.align(&self.ecx) && + // None of the inputs may be a pointer. + !matches!(a1.primitive(), Primitive::Pointer(..)) + && !matches!(b1.primitive(), Primitive::Pointer(..)) + } + _ => false, + }; + if !can_transmute { + return None; } } value.offset(Size::ZERO, to, &self.ecx).discard_err()? diff --git a/tests/coverage/closure_macro.cov-map b/tests/coverage/closure_macro.cov-map index eb5f94d1080..fb4a137d4c8 100644 --- a/tests/coverage/closure_macro.cov-map +++ b/tests/coverage/closure_macro.cov-map @@ -23,19 +23,19 @@ Number of file 0 mappings: 6 - Code(Counter(0)) at (prev + 3, 1) to (start + 0, 2) Function name: closure_macro::main::{closure#0} -Raw bytes (35): 0x[01, 01, 03, 01, 05, 05, 0b, 09, 00, 05, 01, 10, 1c, 03, 21, 05, 04, 11, 01, 27, 02, 03, 11, 00, 16, 00, 00, 17, 00, 1e, 07, 02, 09, 00, 0a] +Raw bytes (35): 0x[01, 01, 03, 01, 05, 05, 0b, 09, 0d, 05, 01, 10, 1c, 03, 21, 05, 04, 11, 01, 27, 02, 03, 11, 00, 16, 0d, 00, 17, 00, 1e, 07, 02, 09, 00, 0a] Number of files: 1 - file 0 => global file 1 Number of expressions: 3 - expression 0 operands: lhs = Counter(0), rhs = Counter(1) - expression 1 operands: lhs = Counter(1), rhs = Expression(2, Add) -- expression 2 operands: lhs = Counter(2), rhs = Zero +- expression 2 operands: lhs = Counter(2), rhs = Counter(3) Number of file 0 mappings: 5 - Code(Counter(0)) at (prev + 16, 28) to (start + 3, 33) - Code(Counter(1)) at (prev + 4, 17) to (start + 1, 39) - Code(Expression(0, Sub)) at (prev + 3, 17) to (start + 0, 22) = (c0 - c1) -- Code(Zero) at (prev + 0, 23) to (start + 0, 30) +- Code(Counter(3)) at (prev + 0, 23) to (start + 0, 30) - Code(Expression(1, Add)) at (prev + 2, 9) to (start + 0, 10) - = (c1 + (c2 + Zero)) + = (c1 + (c2 + c3)) diff --git a/tests/coverage/closure_macro_async.cov-map b/tests/coverage/closure_macro_async.cov-map index 4d0597f58bf..091e87909f9 100644 --- a/tests/coverage/closure_macro_async.cov-map +++ b/tests/coverage/closure_macro_async.cov-map @@ -31,19 +31,19 @@ Number of file 0 mappings: 6 - Code(Counter(0)) at (prev + 3, 1) to (start + 0, 2) Function name: closure_macro_async::test::{closure#0}::{closure#0} -Raw bytes (35): 0x[01, 01, 03, 01, 05, 05, 0b, 09, 00, 05, 01, 15, 1c, 03, 21, 05, 04, 11, 01, 27, 02, 03, 11, 00, 16, 00, 00, 17, 00, 1e, 07, 02, 09, 00, 0a] +Raw bytes (35): 0x[01, 01, 03, 01, 05, 05, 0b, 09, 0d, 05, 01, 15, 1c, 03, 21, 05, 04, 11, 01, 27, 02, 03, 11, 00, 16, 0d, 00, 17, 00, 1e, 07, 02, 09, 00, 0a] Number of files: 1 - file 0 => global file 1 Number of expressions: 3 - expression 0 operands: lhs = Counter(0), rhs = Counter(1) - expression 1 operands: lhs = Counter(1), rhs = Expression(2, Add) -- expression 2 operands: lhs = Counter(2), rhs = Zero +- expression 2 operands: lhs = Counter(2), rhs = Counter(3) Number of file 0 mappings: 5 - Code(Counter(0)) at (prev + 21, 28) to (start + 3, 33) - Code(Counter(1)) at (prev + 4, 17) to (start + 1, 39) - Code(Expression(0, Sub)) at (prev + 3, 17) to (start + 0, 22) = (c0 - c1) -- Code(Zero) at (prev + 0, 23) to (start + 0, 30) +- Code(Counter(3)) at (prev + 0, 23) to (start + 0, 30) - Code(Expression(1, Add)) at (prev + 2, 9) to (start + 0, 10) - = (c1 + (c2 + Zero)) + = (c1 + (c2 + c3)) |