stop using ParamEnv::reveal while handling MIR

This commit is contained in:
lcnr 2024-10-31 12:41:50 +01:00
parent 563c473e8d
commit 2cde638ac0
14 changed files with 100 additions and 60 deletions

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@ -589,7 +589,7 @@ fn visit_terminator(&mut self, terminator: &Terminator<'tcx>, location: Location
// Typeck only does a "non-const" check since it operates on HIR and cannot distinguish
// which path expressions are getting called on and which path expressions are only used
// as function pointers. This is required for correctness.
let infcx = tcx.infer_ctxt().build(body.phase.typing_mode());
let infcx = tcx.infer_ctxt().build(body.typing_mode(tcx));
let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
let predicates = tcx.predicates_of(callee).instantiate(tcx, fn_args);

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@ -116,7 +116,7 @@ fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, _: Span) -> Diag<'tcx> {
let obligation =
Obligation::new(tcx, ObligationCause::dummy(), param_env, trait_ref);
let infcx = tcx.infer_ctxt().build(body.phase.typing_mode());
let infcx = tcx.infer_ctxt().build(body.typing_mode(tcx));
let mut selcx = SelectionContext::new(&infcx);
let implsrc = selcx.select(&obligation);

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@ -3,7 +3,7 @@
use rustc_hir::def_id::DefId;
use rustc_infer::infer::TyCtxtInferExt;
use rustc_infer::infer::at::ToTrace;
use rustc_infer::traits::ObligationCause;
use rustc_infer::traits::{ObligationCause, Reveal};
use rustc_middle::mir::interpret::{ErrorHandled, InvalidMetaKind, ReportedErrorInfo};
use rustc_middle::query::TyCtxtAt;
use rustc_middle::ty::layout::{
@ -116,6 +116,7 @@ fn handle_fn_abi_err(
/// This test should be symmetric, as it is primarily about layout compatibility.
pub(super) fn mir_assign_valid_types<'tcx>(
tcx: TyCtxt<'tcx>,
typing_mode: TypingMode<'tcx>,
param_env: ParamEnv<'tcx>,
src: TyAndLayout<'tcx>,
dest: TyAndLayout<'tcx>,
@ -124,7 +125,7 @@ pub(super) fn mir_assign_valid_types<'tcx>(
// all normal lifetimes are erased, higher-ranked types with their
// late-bound lifetimes are still around and can lead to type
// differences.
if util::relate_types(tcx, param_env, Variance::Covariant, src.ty, dest.ty) {
if util::relate_types(tcx, typing_mode, param_env, Variance::Covariant, src.ty, dest.ty) {
// Make sure the layout is equal, too -- just to be safe. Miri really
// needs layout equality. For performance reason we skip this check when
// the types are equal. Equal types *can* have different layouts when
@ -144,6 +145,7 @@ pub(super) fn mir_assign_valid_types<'tcx>(
#[cfg_attr(not(debug_assertions), inline(always))]
pub(super) fn from_known_layout<'tcx>(
tcx: TyCtxtAt<'tcx>,
typing_mode: TypingMode<'tcx>,
param_env: ParamEnv<'tcx>,
known_layout: Option<TyAndLayout<'tcx>>,
compute: impl FnOnce() -> InterpResult<'tcx, TyAndLayout<'tcx>>,
@ -153,7 +155,13 @@ pub(super) fn from_known_layout<'tcx>(
Some(known_layout) => {
if cfg!(debug_assertions) {
let check_layout = compute()?;
if !mir_assign_valid_types(tcx.tcx, param_env, check_layout, known_layout) {
if !mir_assign_valid_types(
tcx.tcx,
typing_mode,
param_env,
check_layout,
known_layout,
) {
span_bug!(
tcx.span,
"expected type differs from actual type.\nexpected: {}\nactual: {}",
@ -203,6 +211,11 @@ pub fn new(
}
}
pub fn typing_mode(&self) -> TypingMode<'tcx> {
debug_assert_eq!(self.param_env.reveal(), Reveal::All);
TypingMode::PostAnalysis
}
/// Returns the span of the currently executed statement/terminator.
/// This is the span typically used for error reporting.
#[inline(always)]
@ -327,7 +340,7 @@ pub(super) fn eq_in_param_env<T>(&self, a: T, b: T) -> bool
return true;
}
// Slow path: spin up an inference context to check if these traits are sufficiently equal.
let infcx = self.tcx.infer_ctxt().build(TypingMode::from_param_env(self.param_env));
let infcx = self.tcx.infer_ctxt().build(self.typing_mode());
let ocx = ObligationCtxt::new(&infcx);
let cause = ObligationCause::dummy_with_span(self.cur_span());
// equate the two trait refs after normalization

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@ -773,6 +773,7 @@ pub fn eval_place_to_op(
)?;
if !mir_assign_valid_types(
*self.tcx,
self.typing_mode(),
self.param_env,
self.layout_of(normalized_place_ty)?,
op.layout,
@ -832,7 +833,9 @@ pub(crate) fn const_val_to_op(
})
};
let layout =
from_known_layout(self.tcx, self.param_env, layout, || self.layout_of(ty).into())?;
from_known_layout(self.tcx, self.typing_mode(), self.param_env, layout, || {
self.layout_of(ty).into()
})?;
let imm = match val_val {
mir::ConstValue::Indirect { alloc_id, offset } => {
// This is const data, no mutation allowed.

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@ -540,6 +540,7 @@ pub fn eval_place(
)?;
if !mir_assign_valid_types(
*self.tcx,
self.typing_mode(),
self.param_env,
self.layout_of(normalized_place_ty)?,
place.layout,
@ -870,8 +871,13 @@ fn copy_op_no_validate(
) -> InterpResult<'tcx> {
// We do NOT compare the types for equality, because well-typed code can
// actually "transmute" `&mut T` to `&T` in an assignment without a cast.
let layout_compat =
mir_assign_valid_types(*self.tcx, self.param_env, src.layout(), dest.layout());
let layout_compat = mir_assign_valid_types(
*self.tcx,
self.typing_mode(),
self.param_env,
src.layout(),
dest.layout(),
);
if !allow_transmute && !layout_compat {
span_bug!(
self.cur_span(),

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@ -596,12 +596,13 @@ pub(super) fn layout_of_local(
return interp_ok(layout);
}
let layout = from_known_layout(self.tcx, self.param_env, layout, || {
let local_ty = frame.body.local_decls[local].ty;
let local_ty =
self.instantiate_from_frame_and_normalize_erasing_regions(frame, local_ty)?;
self.layout_of(local_ty).into()
})?;
let layout =
from_known_layout(self.tcx, self.typing_mode(), self.param_env, layout, || {
let local_ty = frame.body.local_decls[local].ty;
let local_ty =
self.instantiate_from_frame_and_normalize_erasing_regions(frame, local_ty)?;
self.layout_of(local_ty).into()
})?;
// Layouts of locals are requested a lot, so we cache them.
state.layout.set(Some(layout));

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@ -8,24 +8,15 @@
use rustc_middle::ty::{ParamEnv, Ty, TyCtxt, TypingMode, Variance};
use rustc_trait_selection::traits::ObligationCtxt;
/// Returns whether the two types are equal up to subtyping.
///
/// This is used in case we don't know the expected subtyping direction
/// and still want to check whether anything is broken.
pub fn is_equal_up_to_subtyping<'tcx>(
/// Returns whether `src` is a subtype of `dest`, i.e. `src <: dest`.
pub fn sub_types<'tcx>(
tcx: TyCtxt<'tcx>,
typing_mode: TypingMode<'tcx>,
param_env: ParamEnv<'tcx>,
src: Ty<'tcx>,
dest: Ty<'tcx>,
) -> bool {
// Fast path.
if src == dest {
return true;
}
// Check for subtyping in either direction.
relate_types(tcx, param_env, Variance::Covariant, src, dest)
|| relate_types(tcx, param_env, Variance::Covariant, dest, src)
relate_types(tcx, typing_mode, param_env, Variance::Covariant, src, dest)
}
/// Returns whether `src` is a subtype of `dest`, i.e. `src <: dest`.
@ -35,6 +26,7 @@ pub fn is_equal_up_to_subtyping<'tcx>(
/// because we want to check for type equality.
pub fn relate_types<'tcx>(
tcx: TyCtxt<'tcx>,
typing_mode: TypingMode<'tcx>,
param_env: ParamEnv<'tcx>,
variance: Variance,
src: Ty<'tcx>,
@ -45,8 +37,7 @@ pub fn relate_types<'tcx>(
}
let mut builder = tcx.infer_ctxt().ignoring_regions();
// FIXME(#132279): This should eventually use the already defined hidden types.
let infcx = builder.build(TypingMode::from_param_env(param_env));
let infcx = builder.build(typing_mode);
let ocx = ObligationCtxt::new(&infcx);
let cause = ObligationCause::dummy();
let src = ocx.normalize(&cause, param_env, src);

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@ -8,7 +8,7 @@
pub use self::alignment::{is_disaligned, is_within_packed};
pub use self::check_validity_requirement::check_validity_requirement;
pub use self::compare_types::{is_equal_up_to_subtyping, relate_types};
pub use self::compare_types::{relate_types, sub_types};
pub use self::type_name::type_name;
/// Classify whether an operator is "left-homogeneous", i.e., the LHS has the

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@ -39,7 +39,7 @@
use crate::ty::print::{FmtPrinter, Printer, pretty_print_const, with_no_trimmed_paths};
use crate::ty::visit::TypeVisitableExt;
use crate::ty::{
self, AdtDef, GenericArg, GenericArgsRef, Instance, InstanceKind, List, Ty, TyCtxt,
self, AdtDef, GenericArg, GenericArgsRef, Instance, InstanceKind, List, Ty, TyCtxt, TypingMode,
UserTypeAnnotationIndex,
};
@ -452,6 +452,15 @@ pub fn basic_blocks_mut(&mut self) -> &mut IndexVec<BasicBlock, BasicBlockData<'
self.basic_blocks.as_mut()
}
pub fn typing_mode(&self, _tcx: TyCtxt<'tcx>) -> TypingMode<'tcx> {
match self.phase {
// FIXME(#132279): the MIR is quite clearly inside of a body, so we
// should instead reveal opaques defined by that body here.
MirPhase::Built | MirPhase::Analysis(_) => TypingMode::non_body_analysis(),
MirPhase::Runtime(_) => TypingMode::PostAnalysis,
}
}
#[inline]
pub fn local_kind(&self, local: Local) -> LocalKind {
let index = local.as_usize();

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@ -20,9 +20,7 @@
use super::{BasicBlock, Const, Local, UserTypeProjection};
use crate::mir::coverage::CoverageKind;
use crate::ty::adjustment::PointerCoercion;
use crate::ty::{
self, GenericArgsRef, List, Region, Ty, TyCtxt, TypingMode, UserTypeAnnotationIndex,
};
use crate::ty::{self, GenericArgsRef, List, Region, Ty, TyCtxt, UserTypeAnnotationIndex};
/// Represents the "flavors" of MIR.
///
@ -103,20 +101,10 @@ pub fn name(&self) -> &'static str {
}
}
pub fn typing_mode<'tcx>(&self) -> TypingMode<'tcx> {
match self {
// FIXME(#132279): the MIR is quite clearly inside of a body, so we
// should instead reveal opaques defined by that body here.
MirPhase::Built | MirPhase::Analysis(_) => TypingMode::non_body_analysis(),
MirPhase::Runtime(_) => TypingMode::PostAnalysis,
}
}
pub fn param_env<'tcx>(&self, tcx: TyCtxt<'tcx>, body_def_id: DefId) -> ty::ParamEnv<'tcx> {
match self.typing_mode() {
TypingMode::Coherence => unreachable!(),
TypingMode::Analysis { defining_opaque_types: _ } => tcx.param_env(body_def_id),
TypingMode::PostAnalysis => tcx.param_env_reveal_all_normalized(body_def_id),
match self {
MirPhase::Built | MirPhase::Analysis(_) => tcx.param_env(body_def_id),
MirPhase::Runtime(_) => tcx.param_env_reveal_all_normalized(body_def_id),
}
}
}

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@ -244,8 +244,13 @@ fn try_inlining(
// Normally, this shouldn't be required, but trait normalization failure can create a
// validation ICE.
let output_type = callee_body.return_ty();
if !util::relate_types(self.tcx, self.param_env, ty::Covariant, output_type, destination_ty)
{
if !util::sub_types(
self.tcx,
caller_body.typing_mode(self.tcx),
self.param_env,
output_type,
destination_ty,
) {
trace!(?output_type, ?destination_ty);
return Err("failed to normalize return type");
}
@ -275,8 +280,13 @@ fn try_inlining(
self_arg_ty.into_iter().chain(arg_tuple_tys).zip(callee_body.args_iter())
{
let input_type = callee_body.local_decls[input].ty;
if !util::relate_types(self.tcx, self.param_env, ty::Covariant, input_type, arg_ty)
{
if !util::sub_types(
self.tcx,
caller_body.typing_mode(self.tcx),
self.param_env,
input_type,
arg_ty,
) {
trace!(?arg_ty, ?input_type);
return Err("failed to normalize tuple argument type");
}
@ -285,8 +295,13 @@ fn try_inlining(
for (arg, input) in args.iter().zip(callee_body.args_iter()) {
let input_type = callee_body.local_decls[input].ty;
let arg_ty = arg.node.ty(&caller_body.local_decls, self.tcx);
if !util::relate_types(self.tcx, self.param_env, ty::Covariant, input_type, arg_ty)
{
if !util::sub_types(
self.tcx,
caller_body.typing_mode(self.tcx),
self.param_env,
input_type,
arg_ty,
) {
trace!(?arg_ty, ?input_type);
return Err("failed to normalize argument type");
}

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@ -20,7 +20,7 @@
use rustc_trait_selection::traits::ObligationCtxt;
use rustc_type_ir::Upcast;
use crate::util::{is_within_packed, relate_types};
use crate::util::{self, is_within_packed};
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
enum EdgeKind {
@ -583,7 +583,14 @@ fn mir_assign_valid_types(&self, src: Ty<'tcx>, dest: Ty<'tcx>) -> bool {
Variance::Covariant
};
crate::util::relate_types(self.tcx, self.param_env, variance, src, dest)
crate::util::relate_types(
self.tcx,
self.body.typing_mode(self.tcx),
self.param_env,
variance,
src,
dest,
)
}
/// Check that the given predicate definitely holds in the param-env of this MIR body.
@ -602,7 +609,7 @@ fn predicate_must_hold_modulo_regions(
return true;
}
let infcx = self.tcx.infer_ctxt().build(self.body.phase.typing_mode());
let infcx = self.tcx.infer_ctxt().build(self.body.typing_mode(self.tcx));
let ocx = ObligationCtxt::new(&infcx);
ocx.register_obligation(Obligation::new(
self.tcx,
@ -794,10 +801,10 @@ fn visit_projection_elem(
}
}
ProjectionElem::Subtype(ty) => {
if !relate_types(
if !util::sub_types(
self.tcx,
self.body.typing_mode(self.tcx),
self.param_env,
Variance::Covariant,
ty,
place_ref.ty(&self.body.local_decls, self.tcx).ty,
) {

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@ -12,6 +12,13 @@
/// The current typing mode of an inference context. We unfortunately have some
/// slightly different typing rules depending on the current context. See the
/// doc comment for each variant for how and why they are used.
///
/// In most cases you can get the correct typing mode automically via:
/// - `mir::Body::typing_mode`
/// - `rustc_lint::LateContext::typing_mode`
///
/// If neither of these functions are available, feel free to reach out to
/// t-types for help.
#[derive_where(Clone, Copy, Hash, PartialEq, Eq, Debug; I: Interner)]
#[cfg_attr(feature = "nightly", derive(TyEncodable, TyDecodable, HashStable_NoContext))]
pub enum TypingMode<I: Interner> {

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@ -420,7 +420,7 @@ fn is_ty_const_destruct_unused<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, body: &Bod
TraitRef::new(tcx, tcx.require_lang_item(LangItem::Destruct, Some(body.span)), [ty]),
);
let infcx = tcx.infer_ctxt().build(body.phase.typing_mode());
let infcx = tcx.infer_ctxt().build(body.typing_mode(tcx));
let mut selcx = SelectionContext::new(&infcx);
let Some(impl_src) = selcx.select(&obligation).ok().flatten() else {
return false;