Auto merge of rust-lang#77430 - ecstatic-morse:mir-source-in-body, r=lcnr

Store a `MirSource` inside every `Body`

Resolves rust-lang#77427.

r? `@ghost`

Author: bors

compiler/rustc_middle/src/mir/mod.rs

@@ -10,12 +10,11 @@ use crate::ty::codec::{TyDecoder, TyEncoder};
 use crate::ty::fold::{TypeFoldable, TypeFolder, TypeVisitor};
 use crate::ty::print::{FmtPrinter, Printer};
 use crate::ty::subst::{Subst, SubstsRef};
-use crate::ty::{
-    self, AdtDef, CanonicalUserTypeAnnotations, List, Region, Ty, TyCtxt, UserTypeAnnotationIndex,
-};
+use crate::ty::{self, List, Ty, TyCtxt};
+use crate::ty::{AdtDef, InstanceDef, Region, UserTypeAnnotationIndex};
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, Namespace};
-use rustc_hir::def_id::DefId;
+use rustc_hir::def_id::{DefId, CRATE_DEF_INDEX};
 use rustc_hir::{self, GeneratorKind};
 use rustc_target::abi::VariantIdx;
 
@@ -112,6 +111,38 @@ impl MirPhase {
     }
 }
 
+/// Where a specific `mir::Body` comes from.
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(HashStable, TyEncodable, TyDecodable, TypeFoldable)]
+pub struct MirSource<'tcx> {
+    pub instance: InstanceDef<'tcx>,
+
+    /// If `Some`, this is a promoted rvalue within the parent function.
+    pub promoted: Option<Promoted>,
+}
+
+impl<'tcx> MirSource<'tcx> {
+    pub fn item(def_id: DefId) -> Self {
+        MirSource {
+            instance: InstanceDef::Item(ty::WithOptConstParam::unknown(def_id)),
+            promoted: None,
+        }
+    }
+
+    pub fn from_instance(instance: InstanceDef<'tcx>) -> Self {
+        MirSource { instance, promoted: None }
+    }
+
+    pub fn with_opt_param(self) -> ty::WithOptConstParam<DefId> {
+        self.instance.with_opt_param()
+    }
+
+    #[inline]
+    pub fn def_id(&self) -> DefId {
+        self.instance.def_id()
+    }
+}
+
 /// The lowered representation of a single function.
 #[derive(Clone, TyEncodable, TyDecodable, Debug, HashStable, TypeFoldable)]
 pub struct Body<'tcx> {
@@ -126,6 +157,8 @@ pub struct Body<'tcx> {
     /// us to see the difference and forego optimization on the inlined promoted items.
     pub phase: MirPhase,
 
+    pub source: MirSource<'tcx>,
+
     /// A list of source scopes; these are referenced by statements
     /// and used for debuginfo. Indexed by a `SourceScope`.
     pub source_scopes: IndexVec<SourceScope, SourceScopeData>,
@@ -151,7 +184,7 @@ pub struct Body<'tcx> {
     pub local_decls: LocalDecls<'tcx>,
 
     /// User type annotations.
-    pub user_type_annotations: CanonicalUserTypeAnnotations<'tcx>,
+    pub user_type_annotations: ty::CanonicalUserTypeAnnotations<'tcx>,
 
     /// The number of arguments this function takes.
     ///
@@ -209,10 +242,11 @@ pub struct Body<'tcx> {
 
 impl<'tcx> Body<'tcx> {
     pub fn new(
+        source: MirSource<'tcx>,
         basic_blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>,
         source_scopes: IndexVec<SourceScope, SourceScopeData>,
         local_decls: LocalDecls<'tcx>,
-        user_type_annotations: CanonicalUserTypeAnnotations<'tcx>,
+        user_type_annotations: ty::CanonicalUserTypeAnnotations<'tcx>,
         arg_count: usize,
         var_debug_info: Vec<VarDebugInfo<'tcx>>,
         span: Span,
@@ -228,6 +262,7 @@ impl<'tcx> Body<'tcx> {
 
         let mut body = Body {
             phase: MirPhase::Build,
+            source,
             basic_blocks,
             source_scopes,
             yield_ty: None,
@@ -257,6 +292,7 @@ impl<'tcx> Body<'tcx> {
     pub fn new_cfg_only(basic_blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>) -> Self {
         let mut body = Body {
             phase: MirPhase::Build,
+            source: MirSource::item(DefId::local(CRATE_DEF_INDEX)),
             basic_blocks,
             source_scopes: IndexVec::new(),
             yield_ty: None,

compiler/rustc_middle/src/ty/instance.rs

@@ -22,7 +22,8 @@ pub struct Instance<'tcx> {
     pub substs: SubstsRef<'tcx>,
 }
 
-#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, TyEncodable, TyDecodable, HashStable)]
+#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
+#[derive(TyEncodable, TyDecodable, HashStable, TypeFoldable)]
 pub enum InstanceDef<'tcx> {
     /// A user-defined callable item.
     ///

compiler/rustc_mir/src/borrow_check/mod.rs

@@ -17,7 +17,7 @@ use rustc_middle::mir::{AggregateKind, BasicBlock, BorrowCheckResult, BorrowKind
 use rustc_middle::mir::{Field, ProjectionElem, Promoted, Rvalue, Statement, StatementKind};
 use rustc_middle::mir::{InlineAsmOperand, Terminator, TerminatorKind};
 use rustc_middle::ty::query::Providers;
-use rustc_middle::ty::{self, InstanceDef, ParamEnv, RegionVid, TyCtxt};
+use rustc_middle::ty::{self, ParamEnv, RegionVid, TyCtxt};
 use rustc_session::lint::builtin::{MUTABLE_BORROW_RESERVATION_CONFLICT, UNUSED_MUT};
 use rustc_span::{Span, Symbol, DUMMY_SP};
 
@@ -36,7 +36,6 @@ use crate::dataflow::indexes::{BorrowIndex, InitIndex, MoveOutIndex, MovePathInd
 use crate::dataflow::move_paths::{InitLocation, LookupResult, MoveData, MoveError};
 use crate::dataflow::MoveDataParamEnv;
 use crate::dataflow::{Analysis, BorrowckFlowState as Flows, BorrowckResults};
-use crate::transform::MirSource;
 
 use self::diagnostics::{AccessKind, RegionName};
 use self::location::LocationTable;
@@ -236,13 +235,7 @@ fn do_mir_borrowck<'a, 'tcx>(
 
     // Dump MIR results into a file, if that is enabled. This let us
     // write unit-tests, as well as helping with debugging.
-    nll::dump_mir_results(
-        infcx,
-        MirSource { instance: InstanceDef::Item(def.to_global()), promoted: None },
-        &body,
-        &regioncx,
-        &opt_closure_req,
-    );
+    nll::dump_mir_results(infcx, &body, &regioncx, &opt_closure_req);
 
     // We also have a `#[rustc_regions]` annotation that causes us to dump
     // information.

compiler/rustc_mir/src/borrow_check/nll.rs

@@ -9,7 +9,7 @@ use rustc_middle::mir::{
     BasicBlock, Body, ClosureOutlivesSubject, ClosureRegionRequirements, LocalKind, Location,
     Promoted,
 };
-use rustc_middle::ty::{self, InstanceDef, RegionKind, RegionVid};
+use rustc_middle::ty::{self, RegionKind, RegionVid};
 use rustc_span::symbol::sym;
 use std::env;
 use std::fmt::Debug;
@@ -24,7 +24,6 @@ use polonius_engine::{Algorithm, Output};
 use crate::dataflow::impls::MaybeInitializedPlaces;
 use crate::dataflow::move_paths::{InitKind, InitLocation, MoveData};
 use crate::dataflow::ResultsCursor;
-use crate::transform::MirSource;
 use crate::util as mir_util;
 use crate::util::pretty;
 
@@ -72,8 +71,7 @@ pub(in crate::borrow_check) fn replace_regions_in_mir<'cx, 'tcx>(
     // Replace all remaining regions with fresh inference variables.
     renumber::renumber_mir(infcx, body, promoted);
 
-    let source = MirSource { instance: InstanceDef::Item(def.to_global()), promoted: None };
-    mir_util::dump_mir(infcx.tcx, None, "renumber", &0, source, body, |_, _| Ok(()));
+    mir_util::dump_mir(infcx.tcx, None, "renumber", &0, body, |_, _| Ok(()));
 
     universal_regions
 }
@@ -315,16 +313,15 @@ pub(in crate::borrow_check) fn compute_regions<'cx, 'tcx>(
 
 pub(super) fn dump_mir_results<'a, 'tcx>(
     infcx: &InferCtxt<'a, 'tcx>,
-    source: MirSource<'tcx>,
     body: &Body<'tcx>,
     regioncx: &RegionInferenceContext<'tcx>,
     closure_region_requirements: &Option<ClosureRegionRequirements<'_>>,
 ) {
-    if !mir_util::dump_enabled(infcx.tcx, "nll", source.def_id()) {
+    if !mir_util::dump_enabled(infcx.tcx, "nll", body.source.def_id()) {
         return;
     }
 
-    mir_util::dump_mir(infcx.tcx, None, "nll", &0, source, body, |pass_where, out| {
+    mir_util::dump_mir(infcx.tcx, None, "nll", &0, body, |pass_where, out| {
         match pass_where {
             // Before the CFG, dump out the values for each region variable.
             PassWhere::BeforeCFG => {
@@ -352,14 +349,14 @@ pub(super) fn dump_mir_results<'a, 'tcx>(
     // Also dump the inference graph constraints as a graphviz file.
     let _: io::Result<()> = try {
         let mut file =
-            pretty::create_dump_file(infcx.tcx, "regioncx.all.dot", None, "nll", &0, source)?;
+            pretty::create_dump_file(infcx.tcx, "regioncx.all.dot", None, "nll", &0, body.source)?;
         regioncx.dump_graphviz_raw_constraints(&mut file)?;
     };
 
     // Also dump the inference graph constraints as a graphviz file.
     let _: io::Result<()> = try {
         let mut file =
-            pretty::create_dump_file(infcx.tcx, "regioncx.scc.dot", None, "nll", &0, source)?;
+            pretty::create_dump_file(infcx.tcx, "regioncx.scc.dot", None, "nll", &0, body.source)?;
         regioncx.dump_graphviz_scc_constraints(&mut file)?;
     };
 }

compiler/rustc_mir/src/shim.rs

@@ -78,8 +78,6 @@ fn make_shim<'tcx>(tcx: TyCtxt<'tcx>, instance: ty::InstanceDef<'tcx>) -> Body<'
     run_passes(
         tcx,
         &mut result,
-        instance,
-        None,
         MirPhase::Const,
         &[&[
             &add_moves_for_packed_drops::AddMovesForPackedDrops,
@@ -163,7 +161,9 @@ fn build_drop_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, ty: Option<Ty<'tcx>>)
     block(&mut blocks, TerminatorKind::Goto { target: return_block });
     block(&mut blocks, TerminatorKind::Return);
 
-    let mut body = new_body(blocks, local_decls_for_sig(&sig, span), sig.inputs().len(), span);
+    let source = MirSource::from_instance(ty::InstanceDef::DropGlue(def_id, ty));
+    let mut body =
+        new_body(source, blocks, local_decls_for_sig(&sig, span), sig.inputs().len(), span);
 
     if let Some(..) = ty {
         // The first argument (index 0), but add 1 for the return value.
@@ -202,12 +202,14 @@ fn build_drop_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, ty: Option<Ty<'tcx>>)
 }
 
 fn new_body<'tcx>(
+    source: MirSource<'tcx>,
     basic_blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>,
     local_decls: IndexVec<Local, LocalDecl<'tcx>>,
     arg_count: usize,
     span: Span,
 ) -> Body<'tcx> {
     Body::new(
+        source,
         basic_blocks,
         IndexVec::from_elem_n(
             SourceScopeData { span, parent_scope: None, local_data: ClearCrossCrate::Clear },
@@ -344,7 +346,11 @@ impl CloneShimBuilder<'tcx> {
     }
 
     fn into_mir(self) -> Body<'tcx> {
-        new_body(self.blocks, self.local_decls, self.sig.inputs().len(), self.span)
+        let source = MirSource::from_instance(ty::InstanceDef::CloneShim(
+            self.def_id,
+            self.sig.inputs_and_output[0],
+        ));
+        new_body(source, self.blocks, self.local_decls, self.sig.inputs().len(), self.span)
     }
 
     fn source_info(&self) -> SourceInfo {
@@ -834,7 +840,8 @@ fn build_call_shim<'tcx>(
         block(&mut blocks, vec![], TerminatorKind::Resume, true);
     }
 
-    let mut body = new_body(blocks, local_decls, sig.inputs().len(), span);
+    let mut body =
+        new_body(MirSource::from_instance(instance), blocks, local_decls, sig.inputs().len(), span);
 
     if let Abi::RustCall = sig.abi {
         body.spread_arg = Some(Local::new(sig.inputs().len()));
@@ -897,18 +904,16 @@ pub fn build_adt_ctor(tcx: TyCtxt<'_>, ctor_id: DefId) -> Body<'_> {
         is_cleanup: false,
     };
 
-    let body =
-        new_body(IndexVec::from_elem_n(start_block, 1), local_decls, sig.inputs().len(), span);
-
-    crate::util::dump_mir(
-        tcx,
-        None,
-        "mir_map",
-        &0,
-        crate::transform::MirSource::item(ctor_id),
-        &body,
-        |_, _| Ok(()),
+    let source = MirSource::item(ctor_id);
+    let body = new_body(
+        source,
+        IndexVec::from_elem_n(start_block, 1),
+        local_decls,
+        sig.inputs().len(),
+        span,
     );
 
+    crate::util::dump_mir(tcx, None, "mir_map", &0, &body, |_, _| Ok(()));
+
     body
 }

compiler/rustc_mir/src/transform/add_call_guards.rs

@@ -1,4 +1,4 @@
-use crate::transform::{MirPass, MirSource};
+use crate::transform::MirPass;
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
@@ -31,7 +31,7 @@ pub use self::AddCallGuards::*;
  */
 
 impl<'tcx> MirPass<'tcx> for AddCallGuards {
-    fn run_pass(&self, _tcx: TyCtxt<'tcx>, _src: MirSource<'tcx>, body: &mut Body<'tcx>) {
+    fn run_pass(&self, _tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         self.add_call_guards(body);
     }
 }

compiler/rustc_mir/src/transform/add_moves_for_packed_drops.rs

@@ -2,7 +2,7 @@ use rustc_hir::def_id::DefId;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 
-use crate::transform::{MirPass, MirSource};
+use crate::transform::MirPass;
 use crate::util;
 use crate::util::patch::MirPatch;
 
@@ -40,9 +40,9 @@ use crate::util::patch::MirPatch;
 pub struct AddMovesForPackedDrops;
 
 impl<'tcx> MirPass<'tcx> for AddMovesForPackedDrops {
-    fn run_pass(&self, tcx: TyCtxt<'tcx>, src: MirSource<'tcx>, body: &mut Body<'tcx>) {
-        debug!("add_moves_for_packed_drops({:?} @ {:?})", src, body.span);
-        add_moves_for_packed_drops(tcx, body, src.def_id());
+    fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
+        debug!("add_moves_for_packed_drops({:?} @ {:?})", body.source, body.span);
+        add_moves_for_packed_drops(tcx, body, body.source.def_id());
     }
 }
 

compiler/rustc_mir/src/transform/add_retag.rs

@@ -4,7 +4,7 @@
 //! of MIR building, and only after this pass we think of the program has having the
 //! normal MIR semantics.
 
-use crate::transform::{MirPass, MirSource};
+use crate::transform::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 
@@ -58,13 +58,13 @@ fn may_be_reference(ty: Ty<'tcx>) -> bool {
 }
 
 impl<'tcx> MirPass<'tcx> for AddRetag {
-    fn run_pass(&self, tcx: TyCtxt<'tcx>, src: MirSource<'tcx>, body: &mut Body<'tcx>) {
+    fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         if !tcx.sess.opts.debugging_opts.mir_emit_retag {
             return;
         }
 
         // We need an `AllCallEdges` pass before we can do any work.
-        super::add_call_guards::AllCallEdges.run_pass(tcx, src, body);
+        super::add_call_guards::AllCallEdges.run_pass(tcx, body);
 
         let (span, arg_count) = (body.span, body.arg_count);
         let (basic_blocks, local_decls) = body.basic_blocks_and_local_decls_mut();

compiler/rustc_mir/src/transform/check_const_item_mutation.rs

@@ -6,12 +6,12 @@ use rustc_middle::ty::TyCtxt;
 use rustc_session::lint::builtin::CONST_ITEM_MUTATION;
 use rustc_span::def_id::DefId;
 
-use crate::transform::{MirPass, MirSource};
+use crate::transform::MirPass;
 
 pub struct CheckConstItemMutation;
 
 impl<'tcx> MirPass<'tcx> for CheckConstItemMutation {
-    fn run_pass(&self, tcx: TyCtxt<'tcx>, _src: MirSource<'tcx>, body: &mut Body<'tcx>) {
+    fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         let mut checker = ConstMutationChecker { body, tcx, target_local: None };
         checker.visit_body(&body);
     }

compiler/rustc_mir/src/transform/check_packed_ref.rs

@@ -3,14 +3,14 @@ use rustc_middle::mir::*;
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_session::lint::builtin::UNALIGNED_REFERENCES;
 
-use crate::transform::{MirPass, MirSource};
+use crate::transform::MirPass;
 use crate::util;
 
 pub struct CheckPackedRef;
 
 impl<'tcx> MirPass<'tcx> for CheckPackedRef {
-    fn run_pass(&self, tcx: TyCtxt<'tcx>, src: MirSource<'tcx>, body: &mut Body<'tcx>) {
-        let param_env = tcx.param_env(src.instance.def_id());
+    fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
+        let param_env = tcx.param_env(body.source.def_id());
         let source_info = SourceInfo::outermost(body.span);
         let mut checker = PackedRefChecker { body, tcx, param_env, source_info };
         checker.visit_body(&body);