1085 lines
37 KiB
Rust
1085 lines
37 KiB
Rust
use crate::build::expr::as_place::PlaceBuilder;
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use crate::build::scope::DropKind;
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use rustc_apfloat::ieee::{Double, Single};
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use rustc_apfloat::Float;
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use rustc_ast::attr;
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use rustc_data_structures::fx::FxHashMap;
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use rustc_data_structures::sorted_map::SortedIndexMultiMap;
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use rustc_errors::ErrorGuaranteed;
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use rustc_hir as hir;
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use rustc_hir::def::DefKind;
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use rustc_hir::def_id::{DefId, LocalDefId};
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use rustc_hir::{CoroutineKind, Node};
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use rustc_index::bit_set::GrowableBitSet;
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use rustc_index::{Idx, IndexSlice, IndexVec};
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use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
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use rustc_middle::hir::place::PlaceBase as HirPlaceBase;
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use rustc_middle::middle::region;
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use rustc_middle::mir::interpret::Scalar;
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use rustc_middle::mir::*;
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use rustc_middle::thir::{
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self, BindingMode, ExprId, LintLevel, LocalVarId, Param, ParamId, PatKind, Thir,
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};
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use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt};
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use rustc_span::symbol::sym;
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use rustc_span::Span;
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use rustc_span::Symbol;
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use rustc_target::abi::FieldIdx;
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use rustc_target::spec::abi::Abi;
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use super::lints;
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pub(crate) fn mir_built(
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tcx: TyCtxt<'_>,
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def: LocalDefId,
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) -> &rustc_data_structures::steal::Steal<Body<'_>> {
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tcx.alloc_steal_mir(mir_build(tcx, def))
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}
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pub(crate) fn closure_saved_names_of_captured_variables<'tcx>(
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tcx: TyCtxt<'tcx>,
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def_id: LocalDefId,
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) -> IndexVec<FieldIdx, Symbol> {
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tcx.closure_captures(def_id)
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.iter()
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.map(|captured_place| {
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let name = captured_place.to_symbol();
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match captured_place.info.capture_kind {
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ty::UpvarCapture::ByValue => name,
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ty::UpvarCapture::ByRef(..) => Symbol::intern(&format!("_ref__{name}")),
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}
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})
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.collect()
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}
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/// Construct the MIR for a given `DefId`.
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fn mir_build<'tcx>(tcx: TyCtxt<'tcx>, def: LocalDefId) -> Body<'tcx> {
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tcx.ensure_with_value().thir_abstract_const(def);
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if let Err(e) = tcx.check_match(def) {
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return construct_error(tcx, def, e);
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}
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let body = match tcx.thir_body(def) {
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Err(error_reported) => construct_error(tcx, def, error_reported),
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Ok((thir, expr)) => {
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let build_mir = |thir: &Thir<'tcx>| match thir.body_type {
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thir::BodyTy::Fn(fn_sig) => construct_fn(tcx, def, thir, expr, fn_sig),
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thir::BodyTy::Const(ty) => construct_const(tcx, def, thir, expr, ty),
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};
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// this must run before MIR dump, because
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// "not all control paths return a value" is reported here.
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//
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// maybe move the check to a MIR pass?
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tcx.ensure().check_liveness(def);
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if tcx.sess.opts.unstable_opts.thir_unsafeck {
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// Don't steal here if THIR unsafeck is being used. Instead
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// steal in unsafeck. This is so that pattern inline constants
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// can be evaluated as part of building the THIR of the parent
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// function without a cycle.
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build_mir(&thir.borrow())
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} else {
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// We ran all queries that depended on THIR at the beginning
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// of `mir_build`, so now we can steal it
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build_mir(&thir.steal())
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}
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}
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};
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lints::check(tcx, &body);
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// The borrow checker will replace all the regions here with its own
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// inference variables. There's no point having non-erased regions here.
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// The exception is `body.user_type_annotations`, which is used unmodified
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// by borrow checking.
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debug_assert!(
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!(body.local_decls.has_free_regions()
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|| body.basic_blocks.has_free_regions()
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|| body.var_debug_info.has_free_regions()
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|| body.yield_ty().has_free_regions()),
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"Unexpected free regions in MIR: {body:?}",
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);
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body
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}
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///////////////////////////////////////////////////////////////////////////
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// BuildMir -- walks a crate, looking for fn items and methods to build MIR from
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#[derive(Debug, PartialEq, Eq)]
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enum BlockFrame {
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/// Evaluation is currently within a statement.
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///
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/// Examples include:
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/// 1. `EXPR;`
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/// 2. `let _ = EXPR;`
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/// 3. `let x = EXPR;`
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Statement {
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/// If true, then statement discards result from evaluating
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/// the expression (such as examples 1 and 2 above).
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ignores_expr_result: bool,
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},
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/// Evaluation is currently within the tail expression of a block.
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///
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/// Example: `{ STMT_1; STMT_2; EXPR }`
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TailExpr {
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/// If true, then the surrounding context of the block ignores
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/// the result of evaluating the block's tail expression.
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///
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/// Example: `let _ = { STMT_1; EXPR };`
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tail_result_is_ignored: bool,
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/// `Span` of the tail expression.
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span: Span,
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},
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/// Generic mark meaning that the block occurred as a subexpression
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/// where the result might be used.
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///
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/// Examples: `foo(EXPR)`, `match EXPR { ... }`
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SubExpr,
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}
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impl BlockFrame {
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fn is_tail_expr(&self) -> bool {
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match *self {
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BlockFrame::TailExpr { .. } => true,
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BlockFrame::Statement { .. } | BlockFrame::SubExpr => false,
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}
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}
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fn is_statement(&self) -> bool {
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match *self {
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BlockFrame::Statement { .. } => true,
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BlockFrame::TailExpr { .. } | BlockFrame::SubExpr => false,
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}
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}
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}
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#[derive(Debug)]
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struct BlockContext(Vec<BlockFrame>);
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struct Builder<'a, 'tcx> {
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tcx: TyCtxt<'tcx>,
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infcx: InferCtxt<'tcx>,
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region_scope_tree: &'tcx region::ScopeTree,
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param_env: ty::ParamEnv<'tcx>,
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thir: &'a Thir<'tcx>,
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cfg: CFG<'tcx>,
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def_id: LocalDefId,
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hir_id: hir::HirId,
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parent_module: DefId,
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check_overflow: bool,
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fn_span: Span,
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arg_count: usize,
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coroutine_kind: Option<CoroutineKind>,
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/// The current set of scopes, updated as we traverse;
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/// see the `scope` module for more details.
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scopes: scope::Scopes<'tcx>,
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/// The block-context: each time we build the code within an thir::Block,
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/// we push a frame here tracking whether we are building a statement or
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/// if we are pushing the tail expression of the block. This is used to
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/// embed information in generated temps about whether they were created
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/// for a block tail expression or not.
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///
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/// It would be great if we could fold this into `self.scopes`
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/// somehow, but right now I think that is very tightly tied to
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/// the code generation in ways that we cannot (or should not)
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/// start just throwing new entries onto that vector in order to
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/// distinguish the context of EXPR1 from the context of EXPR2 in
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/// `{ STMTS; EXPR1 } + EXPR2`.
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block_context: BlockContext,
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/// The current unsafe block in scope
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in_scope_unsafe: Safety,
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/// The vector of all scopes that we have created thus far;
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/// we track this for debuginfo later.
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source_scopes: IndexVec<SourceScope, SourceScopeData<'tcx>>,
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source_scope: SourceScope,
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/// The guard-context: each time we build the guard expression for
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/// a match arm, we push onto this stack, and then pop when we
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/// finish building it.
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guard_context: Vec<GuardFrame>,
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/// Temporaries with fixed indexes. Used so that if-let guards on arms
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/// with an or-pattern are only created once.
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fixed_temps: FxHashMap<ExprId, Local>,
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/// Scope of temporaries that should be deduplicated using [Self::fixed_temps].
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fixed_temps_scope: Option<region::Scope>,
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/// Maps `HirId`s of variable bindings to the `Local`s created for them.
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/// (A match binding can have two locals; the 2nd is for the arm's guard.)
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var_indices: FxHashMap<LocalVarId, LocalsForNode>,
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local_decls: IndexVec<Local, LocalDecl<'tcx>>,
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canonical_user_type_annotations: ty::CanonicalUserTypeAnnotations<'tcx>,
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upvars: CaptureMap<'tcx>,
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unit_temp: Option<Place<'tcx>>,
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var_debug_info: Vec<VarDebugInfo<'tcx>>,
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// A cache for `maybe_lint_level_roots_bounded`. That function is called
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// repeatedly, and each time it effectively traces a path through a tree
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// structure from a node towards the root, doing an attribute check on each
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// node along the way. This cache records which nodes trace all the way to
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// the root (most of them do) and saves us from retracing many sub-paths
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// many times, and rechecking many nodes.
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lint_level_roots_cache: GrowableBitSet<hir::ItemLocalId>,
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}
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type CaptureMap<'tcx> = SortedIndexMultiMap<usize, hir::HirId, Capture<'tcx>>;
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#[derive(Debug)]
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struct Capture<'tcx> {
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captured_place: &'tcx ty::CapturedPlace<'tcx>,
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use_place: Place<'tcx>,
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mutability: Mutability,
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}
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impl<'a, 'tcx> Builder<'a, 'tcx> {
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fn is_bound_var_in_guard(&self, id: LocalVarId) -> bool {
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self.guard_context.iter().any(|frame| frame.locals.iter().any(|local| local.id == id))
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}
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fn var_local_id(&self, id: LocalVarId, for_guard: ForGuard) -> Local {
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self.var_indices[&id].local_id(for_guard)
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}
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}
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impl BlockContext {
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fn new() -> Self {
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BlockContext(vec![])
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}
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fn push(&mut self, bf: BlockFrame) {
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self.0.push(bf);
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}
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fn pop(&mut self) -> Option<BlockFrame> {
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self.0.pop()
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}
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/// Traverses the frames on the `BlockContext`, searching for either
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/// the first block-tail expression frame with no intervening
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/// statement frame.
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///
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/// Notably, this skips over `SubExpr` frames; this method is
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/// meant to be used in the context of understanding the
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/// relationship of a temp (created within some complicated
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/// expression) with its containing expression, and whether the
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/// value of that *containing expression* (not the temp!) is
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/// ignored.
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fn currently_in_block_tail(&self) -> Option<BlockTailInfo> {
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for bf in self.0.iter().rev() {
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match bf {
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BlockFrame::SubExpr => continue,
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BlockFrame::Statement { .. } => break,
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&BlockFrame::TailExpr { tail_result_is_ignored, span } => {
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return Some(BlockTailInfo { tail_result_is_ignored, span });
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}
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}
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}
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None
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}
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/// Looks at the topmost frame on the BlockContext and reports
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/// whether its one that would discard a block tail result.
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///
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/// Unlike `currently_within_ignored_tail_expression`, this does
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/// *not* skip over `SubExpr` frames: here, we want to know
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/// whether the block result itself is discarded.
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fn currently_ignores_tail_results(&self) -> bool {
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match self.0.last() {
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// no context: conservatively assume result is read
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None => false,
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// sub-expression: block result feeds into some computation
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Some(BlockFrame::SubExpr) => false,
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// otherwise: use accumulated is_ignored state.
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Some(
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BlockFrame::TailExpr { tail_result_is_ignored: ignored, .. }
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| BlockFrame::Statement { ignores_expr_result: ignored },
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) => *ignored,
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}
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}
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}
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#[derive(Debug)]
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enum LocalsForNode {
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/// In the usual case, a `HirId` for an identifier maps to at most
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/// one `Local` declaration.
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One(Local),
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/// The exceptional case is identifiers in a match arm's pattern
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/// that are referenced in a guard of that match arm. For these,
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/// we have `2` Locals.
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///
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/// * `for_arm_body` is the Local used in the arm body (which is
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/// just like the `One` case above),
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///
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/// * `ref_for_guard` is the Local used in the arm's guard (which
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/// is a reference to a temp that is an alias of
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/// `for_arm_body`).
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ForGuard { ref_for_guard: Local, for_arm_body: Local },
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}
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#[derive(Debug)]
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struct GuardFrameLocal {
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id: LocalVarId,
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}
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impl GuardFrameLocal {
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fn new(id: LocalVarId, _binding_mode: BindingMode) -> Self {
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GuardFrameLocal { id }
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}
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}
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#[derive(Debug)]
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struct GuardFrame {
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/// These are the id's of names that are bound by patterns of the
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/// arm of *this* guard.
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///
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/// (Frames higher up the stack will have the id's bound in arms
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/// further out, such as in a case like:
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///
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/// match E1 {
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/// P1(id1) if (... (match E2 { P2(id2) if ... => B2 })) => B1,
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/// }
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///
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/// here, when building for FIXME.
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locals: Vec<GuardFrameLocal>,
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}
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/// `ForGuard` indicates whether we are talking about:
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/// 1. The variable for use outside of guard expressions, or
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/// 2. The temp that holds reference to (1.), which is actually what the
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/// guard expressions see.
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#[derive(Copy, Clone, Debug, PartialEq, Eq)]
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enum ForGuard {
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RefWithinGuard,
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OutsideGuard,
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}
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impl LocalsForNode {
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fn local_id(&self, for_guard: ForGuard) -> Local {
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match (self, for_guard) {
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(&LocalsForNode::One(local_id), ForGuard::OutsideGuard)
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| (
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&LocalsForNode::ForGuard { ref_for_guard: local_id, .. },
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ForGuard::RefWithinGuard,
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)
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| (&LocalsForNode::ForGuard { for_arm_body: local_id, .. }, ForGuard::OutsideGuard) => {
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local_id
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}
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(&LocalsForNode::One(_), ForGuard::RefWithinGuard) => {
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bug!("anything with one local should never be within a guard.")
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}
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}
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}
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}
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struct CFG<'tcx> {
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basic_blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>,
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}
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|
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rustc_index::newtype_index! {
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struct ScopeId {}
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}
|
|
|
|
#[derive(Debug)]
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enum NeedsTemporary {
|
|
/// Use this variant when whatever you are converting with `as_operand`
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/// is the last thing you are converting. This means that if we introduced
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/// an intermediate temporary, we'd only read it immediately after, so we can
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/// also avoid it.
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No,
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/// For all cases where you aren't sure or that are too expensive to compute
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/// for now. It is always safe to fall back to this.
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Maybe,
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}
|
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|
|
///////////////////////////////////////////////////////////////////////////
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|
/// The `BlockAnd` "monad" packages up the new basic block along with a
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/// produced value (sometimes just unit, of course). The `unpack!`
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|
/// macro (and methods below) makes working with `BlockAnd` much more
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/// convenient.
|
|
|
|
#[must_use = "if you don't use one of these results, you're leaving a dangling edge"]
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struct BlockAnd<T>(BasicBlock, T);
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|
|
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trait BlockAndExtension {
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|
fn and<T>(self, v: T) -> BlockAnd<T>;
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fn unit(self) -> BlockAnd<()>;
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|
}
|
|
|
|
impl BlockAndExtension for BasicBlock {
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fn and<T>(self, v: T) -> BlockAnd<T> {
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BlockAnd(self, v)
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|
}
|
|
|
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fn unit(self) -> BlockAnd<()> {
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BlockAnd(self, ())
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}
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}
|
|
|
|
/// Update a block pointer and return the value.
|
|
/// Use it like `let x = unpack!(block = self.foo(block, foo))`.
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|
macro_rules! unpack {
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|
($x:ident = $c:expr) => {{
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let BlockAnd(b, v) = $c;
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$x = b;
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v
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}};
|
|
|
|
($c:expr) => {{
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let BlockAnd(b, ()) = $c;
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b
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}};
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}
|
|
|
|
///////////////////////////////////////////////////////////////////////////
|
|
/// the main entry point for building MIR for a function
|
|
|
|
fn construct_fn<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
fn_def: LocalDefId,
|
|
thir: &Thir<'tcx>,
|
|
expr: ExprId,
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|
fn_sig: ty::FnSig<'tcx>,
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|
) -> Body<'tcx> {
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|
let span = tcx.def_span(fn_def);
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|
let fn_id = tcx.local_def_id_to_hir_id(fn_def);
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|
let coroutine_kind = tcx.coroutine_kind(fn_def);
|
|
|
|
// The representation of thir for `-Zunpretty=thir-tree` relies on
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|
// the entry expression being the last element of `thir.exprs`.
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|
assert_eq!(expr.as_usize(), thir.exprs.len() - 1);
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|
|
// Figure out what primary body this item has.
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|
let body_id = tcx.hir().body_owned_by(fn_def);
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|
let span_with_body = tcx.hir().span_with_body(fn_id);
|
|
let return_ty_span = tcx
|
|
.hir()
|
|
.fn_decl_by_hir_id(fn_id)
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|
.unwrap_or_else(|| span_bug!(span, "can't build MIR for {:?}", fn_def))
|
|
.output
|
|
.span();
|
|
|
|
let safety = match fn_sig.unsafety {
|
|
hir::Unsafety::Normal => Safety::Safe,
|
|
hir::Unsafety::Unsafe => Safety::FnUnsafe,
|
|
};
|
|
|
|
let mut abi = fn_sig.abi;
|
|
if let DefKind::Closure = tcx.def_kind(fn_def) {
|
|
// HACK(eddyb) Avoid having RustCall on closures,
|
|
// as it adds unnecessary (and wrong) auto-tupling.
|
|
abi = Abi::Rust;
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|
}
|
|
|
|
let arguments = &thir.params;
|
|
|
|
let (resume_ty, yield_ty, return_ty) = if coroutine_kind.is_some() {
|
|
let coroutine_ty = arguments[thir::UPVAR_ENV_PARAM].ty;
|
|
let coroutine_sig = match coroutine_ty.kind() {
|
|
ty::Coroutine(_, gen_args, ..) => gen_args.as_coroutine().sig(),
|
|
_ => {
|
|
span_bug!(span, "coroutine w/o coroutine type: {:?}", coroutine_ty)
|
|
}
|
|
};
|
|
(Some(coroutine_sig.resume_ty), Some(coroutine_sig.yield_ty), coroutine_sig.return_ty)
|
|
} else {
|
|
(None, None, fn_sig.output())
|
|
};
|
|
|
|
if let Some(custom_mir_attr) =
|
|
tcx.hir().attrs(fn_id).iter().find(|attr| attr.name_or_empty() == sym::custom_mir)
|
|
{
|
|
return custom::build_custom_mir(
|
|
tcx,
|
|
fn_def.to_def_id(),
|
|
fn_id,
|
|
thir,
|
|
expr,
|
|
arguments,
|
|
return_ty,
|
|
return_ty_span,
|
|
span_with_body,
|
|
custom_mir_attr,
|
|
);
|
|
}
|
|
|
|
let infcx = tcx.infer_ctxt().build();
|
|
let mut builder = Builder::new(
|
|
thir,
|
|
infcx,
|
|
fn_def,
|
|
fn_id,
|
|
span_with_body,
|
|
arguments.len(),
|
|
safety,
|
|
return_ty,
|
|
return_ty_span,
|
|
coroutine_kind,
|
|
);
|
|
|
|
let call_site_scope =
|
|
region::Scope { id: body_id.hir_id.local_id, data: region::ScopeData::CallSite };
|
|
let arg_scope =
|
|
region::Scope { id: body_id.hir_id.local_id, data: region::ScopeData::Arguments };
|
|
let source_info = builder.source_info(span);
|
|
let call_site_s = (call_site_scope, source_info);
|
|
unpack!(builder.in_scope(call_site_s, LintLevel::Inherited, |builder| {
|
|
let arg_scope_s = (arg_scope, source_info);
|
|
// Attribute epilogue to function's closing brace
|
|
let fn_end = span_with_body.shrink_to_hi();
|
|
let return_block =
|
|
unpack!(builder.in_breakable_scope(None, Place::return_place(), fn_end, |builder| {
|
|
Some(builder.in_scope(arg_scope_s, LintLevel::Inherited, |builder| {
|
|
builder.args_and_body(START_BLOCK, arguments, arg_scope, expr)
|
|
}))
|
|
}));
|
|
let source_info = builder.source_info(fn_end);
|
|
builder.cfg.terminate(return_block, source_info, TerminatorKind::Return);
|
|
builder.build_drop_trees();
|
|
return_block.unit()
|
|
}));
|
|
|
|
let mut body = builder.finish();
|
|
|
|
body.spread_arg = if abi == Abi::RustCall {
|
|
// RustCall pseudo-ABI untuples the last argument.
|
|
Some(Local::new(arguments.len()))
|
|
} else {
|
|
None
|
|
};
|
|
|
|
if coroutine_kind.is_some() {
|
|
body.coroutine.as_mut().unwrap().yield_ty = yield_ty;
|
|
body.coroutine.as_mut().unwrap().resume_ty = resume_ty;
|
|
}
|
|
|
|
body
|
|
}
|
|
|
|
fn construct_const<'a, 'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
def: LocalDefId,
|
|
thir: &'a Thir<'tcx>,
|
|
expr: ExprId,
|
|
const_ty: Ty<'tcx>,
|
|
) -> Body<'tcx> {
|
|
let hir_id = tcx.local_def_id_to_hir_id(def);
|
|
|
|
// Figure out what primary body this item has.
|
|
let (span, const_ty_span) = match tcx.hir_node(hir_id) {
|
|
Node::Item(hir::Item {
|
|
kind: hir::ItemKind::Static(ty, _, _) | hir::ItemKind::Const(ty, _, _),
|
|
span,
|
|
..
|
|
})
|
|
| Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Const(ty, _), span, .. })
|
|
| Node::TraitItem(hir::TraitItem {
|
|
kind: hir::TraitItemKind::Const(ty, Some(_)),
|
|
span,
|
|
..
|
|
}) => (*span, ty.span),
|
|
Node::AnonConst(_) | Node::ConstBlock(_) => {
|
|
let span = tcx.def_span(def);
|
|
(span, span)
|
|
}
|
|
_ => span_bug!(tcx.def_span(def), "can't build MIR for {:?}", def),
|
|
};
|
|
|
|
let infcx = tcx.infer_ctxt().build();
|
|
let mut builder = Builder::new(
|
|
thir,
|
|
infcx,
|
|
def,
|
|
hir_id,
|
|
span,
|
|
0,
|
|
Safety::Safe,
|
|
const_ty,
|
|
const_ty_span,
|
|
None,
|
|
);
|
|
|
|
let mut block = START_BLOCK;
|
|
unpack!(block = builder.expr_into_dest(Place::return_place(), block, expr));
|
|
|
|
let source_info = builder.source_info(span);
|
|
builder.cfg.terminate(block, source_info, TerminatorKind::Return);
|
|
|
|
builder.build_drop_trees();
|
|
|
|
builder.finish()
|
|
}
|
|
|
|
/// Construct MIR for an item that has had errors in type checking.
|
|
///
|
|
/// This is required because we may still want to run MIR passes on an item
|
|
/// with type errors, but normal MIR construction can't handle that in general.
|
|
fn construct_error(tcx: TyCtxt<'_>, def_id: LocalDefId, guar: ErrorGuaranteed) -> Body<'_> {
|
|
let span = tcx.def_span(def_id);
|
|
let hir_id = tcx.local_def_id_to_hir_id(def_id);
|
|
let coroutine_kind = tcx.coroutine_kind(def_id);
|
|
|
|
let (inputs, output, resume_ty, yield_ty) = match tcx.def_kind(def_id) {
|
|
DefKind::Const
|
|
| DefKind::AssocConst
|
|
| DefKind::AnonConst
|
|
| DefKind::InlineConst
|
|
| DefKind::Static(_) => (vec![], tcx.type_of(def_id).instantiate_identity(), None, None),
|
|
DefKind::Ctor(..) | DefKind::Fn | DefKind::AssocFn => {
|
|
let sig = tcx.liberate_late_bound_regions(
|
|
def_id.to_def_id(),
|
|
tcx.fn_sig(def_id).instantiate_identity(),
|
|
);
|
|
(sig.inputs().to_vec(), sig.output(), None, None)
|
|
}
|
|
DefKind::Closure if coroutine_kind.is_some() => {
|
|
let coroutine_ty = tcx.type_of(def_id).instantiate_identity();
|
|
let ty::Coroutine(_, args) = coroutine_ty.kind() else {
|
|
bug!("expected type of coroutine-like closure to be a coroutine")
|
|
};
|
|
let args = args.as_coroutine();
|
|
let resume_ty = args.resume_ty();
|
|
let yield_ty = args.yield_ty();
|
|
let return_ty = args.return_ty();
|
|
(vec![coroutine_ty, args.resume_ty()], return_ty, Some(resume_ty), Some(yield_ty))
|
|
}
|
|
DefKind::Closure => {
|
|
let closure_ty = tcx.type_of(def_id).instantiate_identity();
|
|
let ty::Closure(_, args) = closure_ty.kind() else {
|
|
bug!("expected type of closure to be a closure")
|
|
};
|
|
let args = args.as_closure();
|
|
let sig = tcx.liberate_late_bound_regions(def_id.to_def_id(), args.sig());
|
|
let self_ty = match args.kind() {
|
|
ty::ClosureKind::Fn => Ty::new_imm_ref(tcx, tcx.lifetimes.re_erased, closure_ty),
|
|
ty::ClosureKind::FnMut => Ty::new_mut_ref(tcx, tcx.lifetimes.re_erased, closure_ty),
|
|
ty::ClosureKind::FnOnce => closure_ty,
|
|
};
|
|
([self_ty].into_iter().chain(sig.inputs().to_vec()).collect(), sig.output(), None, None)
|
|
}
|
|
dk => bug!("{:?} is not a body: {:?}", def_id, dk),
|
|
};
|
|
|
|
let source_info = SourceInfo { span, scope: OUTERMOST_SOURCE_SCOPE };
|
|
let local_decls = IndexVec::from_iter(
|
|
[output].iter().chain(&inputs).map(|ty| LocalDecl::with_source_info(*ty, source_info)),
|
|
);
|
|
let mut cfg = CFG { basic_blocks: IndexVec::new() };
|
|
let mut source_scopes = IndexVec::new();
|
|
|
|
cfg.start_new_block();
|
|
source_scopes.push(SourceScopeData {
|
|
span,
|
|
parent_scope: None,
|
|
inlined: None,
|
|
inlined_parent_scope: None,
|
|
local_data: ClearCrossCrate::Set(SourceScopeLocalData {
|
|
lint_root: hir_id,
|
|
safety: Safety::Safe,
|
|
}),
|
|
});
|
|
|
|
cfg.terminate(START_BLOCK, source_info, TerminatorKind::Unreachable);
|
|
|
|
let mut body = Body::new(
|
|
MirSource::item(def_id.to_def_id()),
|
|
cfg.basic_blocks,
|
|
source_scopes,
|
|
local_decls,
|
|
IndexVec::new(),
|
|
inputs.len(),
|
|
vec![],
|
|
span,
|
|
coroutine_kind,
|
|
Some(guar),
|
|
);
|
|
|
|
body.coroutine.as_mut().map(|gen| {
|
|
gen.yield_ty = yield_ty;
|
|
gen.resume_ty = resume_ty;
|
|
});
|
|
|
|
body
|
|
}
|
|
|
|
impl<'a, 'tcx> Builder<'a, 'tcx> {
|
|
fn new(
|
|
thir: &'a Thir<'tcx>,
|
|
infcx: InferCtxt<'tcx>,
|
|
def: LocalDefId,
|
|
hir_id: hir::HirId,
|
|
span: Span,
|
|
arg_count: usize,
|
|
safety: Safety,
|
|
return_ty: Ty<'tcx>,
|
|
return_span: Span,
|
|
coroutine_kind: Option<CoroutineKind>,
|
|
) -> Builder<'a, 'tcx> {
|
|
let tcx = infcx.tcx;
|
|
let attrs = tcx.hir().attrs(hir_id);
|
|
// Some functions always have overflow checks enabled,
|
|
// however, they may not get codegen'd, depending on
|
|
// the settings for the crate they are codegened in.
|
|
let mut check_overflow = attr::contains_name(attrs, sym::rustc_inherit_overflow_checks);
|
|
// Respect -C overflow-checks.
|
|
check_overflow |= tcx.sess.overflow_checks();
|
|
// Constants always need overflow checks.
|
|
check_overflow |= matches!(
|
|
tcx.hir().body_owner_kind(def),
|
|
hir::BodyOwnerKind::Const { .. } | hir::BodyOwnerKind::Static(_)
|
|
);
|
|
|
|
let lint_level = LintLevel::Explicit(hir_id);
|
|
let param_env = tcx.param_env(def);
|
|
let mut builder = Builder {
|
|
thir,
|
|
tcx,
|
|
infcx,
|
|
region_scope_tree: tcx.region_scope_tree(def),
|
|
param_env,
|
|
def_id: def,
|
|
hir_id,
|
|
parent_module: tcx.parent_module(hir_id).to_def_id(),
|
|
check_overflow,
|
|
cfg: CFG { basic_blocks: IndexVec::new() },
|
|
fn_span: span,
|
|
arg_count,
|
|
coroutine_kind,
|
|
scopes: scope::Scopes::new(),
|
|
block_context: BlockContext::new(),
|
|
source_scopes: IndexVec::new(),
|
|
source_scope: OUTERMOST_SOURCE_SCOPE,
|
|
guard_context: vec![],
|
|
fixed_temps: Default::default(),
|
|
fixed_temps_scope: None,
|
|
in_scope_unsafe: safety,
|
|
local_decls: IndexVec::from_elem_n(LocalDecl::new(return_ty, return_span), 1),
|
|
canonical_user_type_annotations: IndexVec::new(),
|
|
upvars: CaptureMap::new(),
|
|
var_indices: Default::default(),
|
|
unit_temp: None,
|
|
var_debug_info: vec![],
|
|
lint_level_roots_cache: GrowableBitSet::new_empty(),
|
|
};
|
|
|
|
assert_eq!(builder.cfg.start_new_block(), START_BLOCK);
|
|
assert_eq!(
|
|
builder.new_source_scope(span, lint_level, Some(safety)),
|
|
OUTERMOST_SOURCE_SCOPE
|
|
);
|
|
builder.source_scopes[OUTERMOST_SOURCE_SCOPE].parent_scope = None;
|
|
|
|
builder
|
|
}
|
|
|
|
fn finish(self) -> Body<'tcx> {
|
|
for (index, block) in self.cfg.basic_blocks.iter().enumerate() {
|
|
if block.terminator.is_none() {
|
|
span_bug!(self.fn_span, "no terminator on block {:?}", index);
|
|
}
|
|
}
|
|
|
|
Body::new(
|
|
MirSource::item(self.def_id.to_def_id()),
|
|
self.cfg.basic_blocks,
|
|
self.source_scopes,
|
|
self.local_decls,
|
|
self.canonical_user_type_annotations,
|
|
self.arg_count,
|
|
self.var_debug_info,
|
|
self.fn_span,
|
|
self.coroutine_kind,
|
|
None,
|
|
)
|
|
}
|
|
|
|
fn insert_upvar_arg(&mut self) {
|
|
let Some(closure_arg) = self.local_decls.get(ty::CAPTURE_STRUCT_LOCAL) else { return };
|
|
|
|
let mut closure_ty = closure_arg.ty;
|
|
let mut closure_env_projs = vec![];
|
|
if let ty::Ref(_, ty, _) = closure_ty.kind() {
|
|
closure_env_projs.push(ProjectionElem::Deref);
|
|
closure_ty = *ty;
|
|
}
|
|
|
|
let upvar_args = match closure_ty.kind() {
|
|
ty::Closure(_, args) => ty::UpvarArgs::Closure(args),
|
|
ty::Coroutine(_, args) => ty::UpvarArgs::Coroutine(args),
|
|
_ => return,
|
|
};
|
|
|
|
// In analyze_closure() in upvar.rs we gathered a list of upvars used by an
|
|
// indexed closure and we stored in a map called closure_min_captures in TypeckResults
|
|
// with the closure's DefId. Here, we run through that vec of UpvarIds for
|
|
// the given closure and use the necessary information to create upvar
|
|
// debuginfo and to fill `self.upvars`.
|
|
let capture_tys = upvar_args.upvar_tys();
|
|
|
|
let tcx = self.tcx;
|
|
self.upvars = tcx
|
|
.closure_captures(self.def_id)
|
|
.iter()
|
|
.zip(capture_tys)
|
|
.enumerate()
|
|
.map(|(i, (captured_place, ty))| {
|
|
let name = captured_place.to_symbol();
|
|
|
|
let capture = captured_place.info.capture_kind;
|
|
let var_id = match captured_place.place.base {
|
|
HirPlaceBase::Upvar(upvar_id) => upvar_id.var_path.hir_id,
|
|
_ => bug!("Expected an upvar"),
|
|
};
|
|
|
|
let mutability = captured_place.mutability;
|
|
|
|
let mut projs = closure_env_projs.clone();
|
|
projs.push(ProjectionElem::Field(FieldIdx::new(i), ty));
|
|
match capture {
|
|
ty::UpvarCapture::ByValue => {}
|
|
ty::UpvarCapture::ByRef(..) => {
|
|
projs.push(ProjectionElem::Deref);
|
|
}
|
|
};
|
|
|
|
let use_place = Place {
|
|
local: ty::CAPTURE_STRUCT_LOCAL,
|
|
projection: tcx.mk_place_elems(&projs),
|
|
};
|
|
self.var_debug_info.push(VarDebugInfo {
|
|
name,
|
|
source_info: SourceInfo::outermost(captured_place.var_ident.span),
|
|
value: VarDebugInfoContents::Place(use_place),
|
|
composite: None,
|
|
argument_index: None,
|
|
});
|
|
|
|
let capture = Capture { captured_place, use_place, mutability };
|
|
(var_id, capture)
|
|
})
|
|
.collect();
|
|
}
|
|
|
|
fn args_and_body(
|
|
&mut self,
|
|
mut block: BasicBlock,
|
|
arguments: &IndexSlice<ParamId, Param<'tcx>>,
|
|
argument_scope: region::Scope,
|
|
expr_id: ExprId,
|
|
) -> BlockAnd<()> {
|
|
let expr_span = self.thir[expr_id].span;
|
|
// Allocate locals for the function arguments
|
|
for (argument_index, param) in arguments.iter().enumerate() {
|
|
let source_info =
|
|
SourceInfo::outermost(param.pat.as_ref().map_or(self.fn_span, |pat| pat.span));
|
|
let arg_local =
|
|
self.local_decls.push(LocalDecl::with_source_info(param.ty, source_info));
|
|
|
|
// If this is a simple binding pattern, give debuginfo a nice name.
|
|
if let Some(ref pat) = param.pat
|
|
&& let Some(name) = pat.simple_ident()
|
|
{
|
|
self.var_debug_info.push(VarDebugInfo {
|
|
name,
|
|
source_info,
|
|
value: VarDebugInfoContents::Place(arg_local.into()),
|
|
composite: None,
|
|
argument_index: Some(argument_index as u16 + 1),
|
|
});
|
|
}
|
|
}
|
|
|
|
self.insert_upvar_arg();
|
|
|
|
let mut scope = None;
|
|
// Bind the argument patterns
|
|
for (index, param) in arguments.iter().enumerate() {
|
|
// Function arguments always get the first Local indices after the return place
|
|
let local = Local::new(index + 1);
|
|
let place = Place::from(local);
|
|
|
|
// Make sure we drop (parts of) the argument even when not matched on.
|
|
self.schedule_drop(
|
|
param.pat.as_ref().map_or(expr_span, |pat| pat.span),
|
|
argument_scope,
|
|
local,
|
|
DropKind::Value,
|
|
);
|
|
|
|
let Some(ref pat) = param.pat else {
|
|
continue;
|
|
};
|
|
let original_source_scope = self.source_scope;
|
|
let span = pat.span;
|
|
if let Some(arg_hir_id) = param.hir_id {
|
|
self.set_correct_source_scope_for_arg(arg_hir_id, original_source_scope, span);
|
|
}
|
|
match pat.kind {
|
|
// Don't introduce extra copies for simple bindings
|
|
PatKind::Binding {
|
|
mutability,
|
|
var,
|
|
mode: BindingMode::ByValue,
|
|
subpattern: None,
|
|
..
|
|
} => {
|
|
self.local_decls[local].mutability = mutability;
|
|
self.local_decls[local].source_info.scope = self.source_scope;
|
|
**self.local_decls[local].local_info.as_mut().assert_crate_local() =
|
|
if let Some(kind) = param.self_kind {
|
|
LocalInfo::User(BindingForm::ImplicitSelf(kind))
|
|
} else {
|
|
let binding_mode = ty::BindingMode::BindByValue(mutability);
|
|
LocalInfo::User(BindingForm::Var(VarBindingForm {
|
|
binding_mode,
|
|
opt_ty_info: param.ty_span,
|
|
opt_match_place: Some((None, span)),
|
|
pat_span: span,
|
|
}))
|
|
};
|
|
self.var_indices.insert(var, LocalsForNode::One(local));
|
|
}
|
|
_ => {
|
|
scope = self.declare_bindings(
|
|
scope,
|
|
expr_span,
|
|
&pat,
|
|
None,
|
|
Some((Some(&place), span)),
|
|
);
|
|
let place_builder = PlaceBuilder::from(local);
|
|
unpack!(block = self.place_into_pattern(block, pat, place_builder, false));
|
|
}
|
|
}
|
|
self.source_scope = original_source_scope;
|
|
}
|
|
|
|
// Enter the argument pattern bindings source scope, if it exists.
|
|
if let Some(source_scope) = scope {
|
|
self.source_scope = source_scope;
|
|
}
|
|
|
|
self.expr_into_dest(Place::return_place(), block, expr_id)
|
|
}
|
|
|
|
fn set_correct_source_scope_for_arg(
|
|
&mut self,
|
|
arg_hir_id: hir::HirId,
|
|
original_source_scope: SourceScope,
|
|
pattern_span: Span,
|
|
) {
|
|
let parent_id = self.source_scopes[original_source_scope]
|
|
.local_data
|
|
.as_ref()
|
|
.assert_crate_local()
|
|
.lint_root;
|
|
self.maybe_new_source_scope(pattern_span, None, arg_hir_id, parent_id);
|
|
}
|
|
|
|
fn get_unit_temp(&mut self) -> Place<'tcx> {
|
|
match self.unit_temp {
|
|
Some(tmp) => tmp,
|
|
None => {
|
|
let ty = Ty::new_unit(self.tcx);
|
|
let fn_span = self.fn_span;
|
|
let tmp = self.temp(ty, fn_span);
|
|
self.unit_temp = Some(tmp);
|
|
tmp
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn parse_float_into_constval<'tcx>(
|
|
num: Symbol,
|
|
float_ty: ty::FloatTy,
|
|
neg: bool,
|
|
) -> Option<ConstValue<'tcx>> {
|
|
parse_float_into_scalar(num, float_ty, neg).map(ConstValue::Scalar)
|
|
}
|
|
|
|
pub(crate) fn parse_float_into_scalar(
|
|
num: Symbol,
|
|
float_ty: ty::FloatTy,
|
|
neg: bool,
|
|
) -> Option<Scalar> {
|
|
let num = num.as_str();
|
|
match float_ty {
|
|
ty::FloatTy::F32 => {
|
|
let Ok(rust_f) = num.parse::<f32>() else { return None };
|
|
let mut f = num
|
|
.parse::<Single>()
|
|
.unwrap_or_else(|e| panic!("apfloat::ieee::Single failed to parse `{num}`: {e:?}"));
|
|
|
|
assert!(
|
|
u128::from(rust_f.to_bits()) == f.to_bits(),
|
|
"apfloat::ieee::Single gave different result for `{}`: \
|
|
{}({:#x}) vs Rust's {}({:#x})",
|
|
rust_f,
|
|
f,
|
|
f.to_bits(),
|
|
Single::from_bits(rust_f.to_bits().into()),
|
|
rust_f.to_bits()
|
|
);
|
|
|
|
if neg {
|
|
f = -f;
|
|
}
|
|
|
|
Some(Scalar::from_f32(f))
|
|
}
|
|
ty::FloatTy::F64 => {
|
|
let Ok(rust_f) = num.parse::<f64>() else { return None };
|
|
let mut f = num
|
|
.parse::<Double>()
|
|
.unwrap_or_else(|e| panic!("apfloat::ieee::Double failed to parse `{num}`: {e:?}"));
|
|
|
|
assert!(
|
|
u128::from(rust_f.to_bits()) == f.to_bits(),
|
|
"apfloat::ieee::Double gave different result for `{}`: \
|
|
{}({:#x}) vs Rust's {}({:#x})",
|
|
rust_f,
|
|
f,
|
|
f.to_bits(),
|
|
Double::from_bits(rust_f.to_bits().into()),
|
|
rust_f.to_bits()
|
|
);
|
|
|
|
if neg {
|
|
f = -f;
|
|
}
|
|
|
|
Some(Scalar::from_f64(f))
|
|
}
|
|
}
|
|
}
|
|
|
|
///////////////////////////////////////////////////////////////////////////
|
|
// Builder methods are broken up into modules, depending on what kind
|
|
// of thing is being lowered. Note that they use the `unpack` macro
|
|
// above extensively.
|
|
|
|
mod block;
|
|
mod cfg;
|
|
mod custom;
|
|
mod expr;
|
|
mod matches;
|
|
mod misc;
|
|
mod scope;
|
|
|
|
pub(crate) use expr::category::Category as ExprCategory;
|