1 use crate::consts::{constant_context, constant_simple};
2 use crate::{differing_macro_contexts, snippet_opt};
3 use rustc_ast::ast::InlineAsmTemplatePiece;
4 use rustc_data_structures::fx::FxHashMap;
5 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
6 use rustc_hir::def::Res;
8 BinOpKind, Block, BlockCheckMode, BodyId, BorrowKind, CaptureBy, Expr, ExprKind, ExprField, PatField, FnRetTy,
9 GenericArg, GenericArgs, Guard, HirId, InlineAsmOperand, Lifetime, LifetimeName, ParamName, Pat, PatKind, Path,
10 PathSegment, QPath, Stmt, StmtKind, Ty, TyKind, TypeBinding,
12 use rustc_lexer::{tokenize, TokenKind};
13 use rustc_lint::LateContext;
14 use rustc_middle::ich::StableHashingContextProvider;
15 use rustc_middle::ty::TypeckResults;
16 use rustc_span::Symbol;
19 /// Type used to check whether two ast are the same. This is different from the
21 /// `==` on ast types as this operator would compare true equality with ID and
24 /// Note that some expressions kinds are not considered but could be added.
25 pub struct SpanlessEq<'a, 'tcx> {
26 /// Context used to evaluate constant expressions.
27 cx: &'a LateContext<'tcx>,
28 maybe_typeck_results: Option<&'tcx TypeckResults<'tcx>>,
29 allow_side_effects: bool,
30 expr_fallback: Option<Box<dyn FnMut(&Expr<'_>, &Expr<'_>) -> bool + 'a>>,
33 impl<'a, 'tcx> SpanlessEq<'a, 'tcx> {
34 pub fn new(cx: &'a LateContext<'tcx>) -> Self {
37 maybe_typeck_results: cx.maybe_typeck_results(),
38 allow_side_effects: true,
43 /// Consider expressions containing potential side effects as not equal.
44 pub fn deny_side_effects(self) -> Self {
46 allow_side_effects: false,
51 pub fn expr_fallback(self, expr_fallback: impl FnMut(&Expr<'_>, &Expr<'_>) -> bool + 'a) -> Self {
53 expr_fallback: Some(Box::new(expr_fallback)),
58 /// Use this method to wrap comparisons that may involve inter-expression context.
59 /// See `self.locals`.
60 fn inter_expr(&mut self) -> HirEqInterExpr<'_, 'a, 'tcx> {
63 locals: FxHashMap::default(),
67 pub fn eq_block(&mut self, left: &Block<'_>, right: &Block<'_>) -> bool {
68 self.inter_expr().eq_block(left, right)
71 pub fn eq_expr(&mut self, left: &Expr<'_>, right: &Expr<'_>) -> bool {
72 self.inter_expr().eq_expr(left, right)
75 pub fn eq_path_segment(&mut self, left: &PathSegment<'_>, right: &PathSegment<'_>) -> bool {
76 self.inter_expr().eq_path_segment(left, right)
79 pub fn eq_path_segments(&mut self, left: &[PathSegment<'_>], right: &[PathSegment<'_>]) -> bool {
80 self.inter_expr().eq_path_segments(left, right)
83 pub fn eq_ty_kind(&mut self, left: &TyKind<'_>, right: &TyKind<'_>) -> bool {
84 self.inter_expr().eq_ty_kind(left, right)
88 struct HirEqInterExpr<'a, 'b, 'tcx> {
89 inner: &'a mut SpanlessEq<'b, 'tcx>,
91 // When binding are declared, the binding ID in the left expression is mapped to the one on the
92 // right. For example, when comparing `{ let x = 1; x + 2 }` and `{ let y = 1; y + 2 }`,
93 // these blocks are considered equal since `x` is mapped to `y`.
94 locals: FxHashMap<HirId, HirId>,
97 impl HirEqInterExpr<'_, '_, '_> {
98 fn eq_stmt(&mut self, left: &Stmt<'_>, right: &Stmt<'_>) -> bool {
99 match (&left.kind, &right.kind) {
100 (&StmtKind::Local(ref l), &StmtKind::Local(ref r)) => {
101 self.eq_pat(&l.pat, &r.pat)
102 && both(&l.ty, &r.ty, |l, r| self.eq_ty(l, r))
103 && both(&l.init, &r.init, |l, r| self.eq_expr(l, r))
105 (&StmtKind::Expr(ref l), &StmtKind::Expr(ref r)) | (&StmtKind::Semi(ref l), &StmtKind::Semi(ref r)) => {
112 /// Checks whether two blocks are the same.
113 fn eq_block(&mut self, left: &Block<'_>, right: &Block<'_>) -> bool {
114 match (left.stmts, left.expr, right.stmts, right.expr) {
115 ([], None, [], None) => {
116 // For empty blocks, check to see if the tokens are equal. This will catch the case where a macro
117 // expanded to nothing, or the cfg attribute was used.
118 let (left, right) = match (
119 snippet_opt(self.inner.cx, left.span),
120 snippet_opt(self.inner.cx, right.span),
122 (Some(left), Some(right)) => (left, right),
125 let mut left_pos = 0;
126 let left = tokenize(&left)
128 let end = left_pos + t.len;
129 let s = &left[left_pos..end];
136 TokenKind::LineComment { .. } | TokenKind::BlockComment { .. } | TokenKind::Whitespace
140 let mut right_pos = 0;
141 let right = tokenize(&right)
143 let end = right_pos + t.len;
144 let s = &right[right_pos..end];
151 TokenKind::LineComment { .. } | TokenKind::BlockComment { .. } | TokenKind::Whitespace
158 over(&left.stmts, &right.stmts, |l, r| self.eq_stmt(l, r))
159 && both(&left.expr, &right.expr, |l, r| self.eq_expr(l, r))
164 #[allow(clippy::similar_names)]
165 fn eq_expr(&mut self, left: &Expr<'_>, right: &Expr<'_>) -> bool {
166 if !self.inner.allow_side_effects && differing_macro_contexts(left.span, right.span) {
170 if let Some(typeck_results) = self.inner.maybe_typeck_results {
171 if let (Some(l), Some(r)) = (
172 constant_simple(self.inner.cx, typeck_results, left),
173 constant_simple(self.inner.cx, typeck_results, right),
182 &reduce_exprkind(self.inner.cx, &left.kind),
183 &reduce_exprkind(self.inner.cx, &right.kind),
185 (&ExprKind::AddrOf(lb, l_mut, ref le), &ExprKind::AddrOf(rb, r_mut, ref re)) => {
186 lb == rb && l_mut == r_mut && self.eq_expr(le, re)
188 (&ExprKind::Continue(li), &ExprKind::Continue(ri)) => {
189 both(&li.label, &ri.label, |l, r| l.ident.name == r.ident.name)
191 (&ExprKind::Assign(ref ll, ref lr, _), &ExprKind::Assign(ref rl, ref rr, _)) => {
192 self.inner.allow_side_effects && self.eq_expr(ll, rl) && self.eq_expr(lr, rr)
194 (&ExprKind::AssignOp(ref lo, ref ll, ref lr), &ExprKind::AssignOp(ref ro, ref rl, ref rr)) => {
195 self.inner.allow_side_effects && lo.node == ro.node && self.eq_expr(ll, rl) && self.eq_expr(lr, rr)
197 (&ExprKind::Block(ref l, _), &ExprKind::Block(ref r, _)) => self.eq_block(l, r),
198 (&ExprKind::Binary(l_op, ref ll, ref lr), &ExprKind::Binary(r_op, ref rl, ref rr)) => {
199 l_op.node == r_op.node && self.eq_expr(ll, rl) && self.eq_expr(lr, rr)
200 || swap_binop(l_op.node, ll, lr).map_or(false, |(l_op, ll, lr)| {
201 l_op == r_op.node && self.eq_expr(ll, rl) && self.eq_expr(lr, rr)
204 (&ExprKind::Break(li, ref le), &ExprKind::Break(ri, ref re)) => {
205 both(&li.label, &ri.label, |l, r| l.ident.name == r.ident.name)
206 && both(le, re, |l, r| self.eq_expr(l, r))
208 (&ExprKind::Box(ref l), &ExprKind::Box(ref r)) => self.eq_expr(l, r),
209 (&ExprKind::Call(l_fun, l_args), &ExprKind::Call(r_fun, r_args)) => {
210 self.inner.allow_side_effects && self.eq_expr(l_fun, r_fun) && self.eq_exprs(l_args, r_args)
212 (&ExprKind::Cast(ref lx, ref lt), &ExprKind::Cast(ref rx, ref rt))
213 | (&ExprKind::Type(ref lx, ref lt), &ExprKind::Type(ref rx, ref rt)) => {
214 self.eq_expr(lx, rx) && self.eq_ty(lt, rt)
216 (&ExprKind::Field(ref l_f_exp, ref l_f_ident), &ExprKind::Field(ref r_f_exp, ref r_f_ident)) => {
217 l_f_ident.name == r_f_ident.name && self.eq_expr(l_f_exp, r_f_exp)
219 (&ExprKind::Index(ref la, ref li), &ExprKind::Index(ref ra, ref ri)) => {
220 self.eq_expr(la, ra) && self.eq_expr(li, ri)
222 (&ExprKind::If(ref lc, ref lt, ref le), &ExprKind::If(ref rc, ref rt, ref re)) => {
223 self.eq_expr(lc, rc) && self.eq_expr(&**lt, &**rt) && both(le, re, |l, r| self.eq_expr(l, r))
225 (&ExprKind::Lit(ref l), &ExprKind::Lit(ref r)) => l.node == r.node,
226 (&ExprKind::Loop(ref lb, ref ll, ref lls, _), &ExprKind::Loop(ref rb, ref rl, ref rls, _)) => {
227 lls == rls && self.eq_block(lb, rb) && both(ll, rl, |l, r| l.ident.name == r.ident.name)
229 (&ExprKind::Match(ref le, ref la, ref ls), &ExprKind::Match(ref re, ref ra, ref rs)) => {
231 && self.eq_expr(le, re)
232 && over(la, ra, |l, r| {
233 self.eq_pat(&l.pat, &r.pat)
234 && both(&l.guard, &r.guard, |l, r| self.eq_guard(l, r))
235 && self.eq_expr(&l.body, &r.body)
238 (&ExprKind::MethodCall(l_path, _, l_args, _), &ExprKind::MethodCall(r_path, _, r_args, _)) => {
239 self.inner.allow_side_effects && self.eq_path_segment(l_path, r_path) && self.eq_exprs(l_args, r_args)
241 (&ExprKind::Repeat(ref le, ref ll_id), &ExprKind::Repeat(ref re, ref rl_id)) => {
242 let mut celcx = constant_context(self.inner.cx, self.inner.cx.tcx.typeck_body(ll_id.body));
243 let ll = celcx.expr(&self.inner.cx.tcx.hir().body(ll_id.body).value);
244 let mut celcx = constant_context(self.inner.cx, self.inner.cx.tcx.typeck_body(rl_id.body));
245 let rl = celcx.expr(&self.inner.cx.tcx.hir().body(rl_id.body).value);
247 self.eq_expr(le, re) && ll == rl
249 (&ExprKind::Ret(ref l), &ExprKind::Ret(ref r)) => both(l, r, |l, r| self.eq_expr(l, r)),
250 (&ExprKind::Path(ref l), &ExprKind::Path(ref r)) => self.eq_qpath(l, r),
251 (&ExprKind::Struct(ref l_path, ref lf, ref lo), &ExprKind::Struct(ref r_path, ref rf, ref ro)) => {
252 self.eq_qpath(l_path, r_path)
253 && both(lo, ro, |l, r| self.eq_expr(l, r))
254 && over(lf, rf, |l, r| self.eq_field(l, r))
256 (&ExprKind::Tup(l_tup), &ExprKind::Tup(r_tup)) => self.eq_exprs(l_tup, r_tup),
257 (&ExprKind::Unary(l_op, ref le), &ExprKind::Unary(r_op, ref re)) => l_op == r_op && self.eq_expr(le, re),
258 (&ExprKind::Array(l), &ExprKind::Array(r)) => self.eq_exprs(l, r),
259 (&ExprKind::DropTemps(ref le), &ExprKind::DropTemps(ref re)) => self.eq_expr(le, re),
262 is_eq || self.inner.expr_fallback.as_mut().map_or(false, |f| f(left, right))
265 fn eq_exprs(&mut self, left: &[Expr<'_>], right: &[Expr<'_>]) -> bool {
266 over(left, right, |l, r| self.eq_expr(l, r))
269 fn eq_field(&mut self, left: &ExprField<'_>, right: &ExprField<'_>) -> bool {
270 left.ident.name == right.ident.name && self.eq_expr(&left.expr, &right.expr)
273 fn eq_guard(&mut self, left: &Guard<'_>, right: &Guard<'_>) -> bool {
274 match (left, right) {
275 (Guard::If(l), Guard::If(r)) => self.eq_expr(l, r),
276 (Guard::IfLet(lp, le), Guard::IfLet(rp, re)) => self.eq_pat(lp, rp) && self.eq_expr(le, re),
281 fn eq_generic_arg(&mut self, left: &GenericArg<'_>, right: &GenericArg<'_>) -> bool {
282 match (left, right) {
283 (GenericArg::Lifetime(l_lt), GenericArg::Lifetime(r_lt)) => Self::eq_lifetime(l_lt, r_lt),
284 (GenericArg::Type(l_ty), GenericArg::Type(r_ty)) => self.eq_ty(l_ty, r_ty),
289 fn eq_lifetime(left: &Lifetime, right: &Lifetime) -> bool {
290 left.name == right.name
293 fn eq_fieldpat(&mut self, left: &PatField<'_>, right: &PatField<'_>) -> bool {
294 let (PatField { ident: li, pat: lp, .. }, PatField { ident: ri, pat: rp, .. }) = (&left, &right);
295 li.name == ri.name && self.eq_pat(lp, rp)
298 /// Checks whether two patterns are the same.
299 fn eq_pat(&mut self, left: &Pat<'_>, right: &Pat<'_>) -> bool {
300 match (&left.kind, &right.kind) {
301 (&PatKind::Box(ref l), &PatKind::Box(ref r)) => self.eq_pat(l, r),
302 (&PatKind::Struct(ref lp, ref la, ..), &PatKind::Struct(ref rp, ref ra, ..)) => {
303 self.eq_qpath(lp, rp) && over(la, ra, |l, r| self.eq_fieldpat(l, r))
305 (&PatKind::TupleStruct(ref lp, ref la, ls), &PatKind::TupleStruct(ref rp, ref ra, rs)) => {
306 self.eq_qpath(lp, rp) && over(la, ra, |l, r| self.eq_pat(l, r)) && ls == rs
308 (&PatKind::Binding(lb, li, _, ref lp), &PatKind::Binding(rb, ri, _, ref rp)) => {
309 let eq = lb == rb && both(lp, rp, |l, r| self.eq_pat(l, r));
311 self.locals.insert(li, ri);
315 (&PatKind::Path(ref l), &PatKind::Path(ref r)) => self.eq_qpath(l, r),
316 (&PatKind::Lit(ref l), &PatKind::Lit(ref r)) => self.eq_expr(l, r),
317 (&PatKind::Tuple(ref l, ls), &PatKind::Tuple(ref r, rs)) => {
318 ls == rs && over(l, r, |l, r| self.eq_pat(l, r))
320 (&PatKind::Range(ref ls, ref le, li), &PatKind::Range(ref rs, ref re, ri)) => {
321 both(ls, rs, |a, b| self.eq_expr(a, b)) && both(le, re, |a, b| self.eq_expr(a, b)) && (li == ri)
323 (&PatKind::Ref(ref le, ref lm), &PatKind::Ref(ref re, ref rm)) => lm == rm && self.eq_pat(le, re),
324 (&PatKind::Slice(ref ls, ref li, ref le), &PatKind::Slice(ref rs, ref ri, ref re)) => {
325 over(ls, rs, |l, r| self.eq_pat(l, r))
326 && over(le, re, |l, r| self.eq_pat(l, r))
327 && both(li, ri, |l, r| self.eq_pat(l, r))
329 (&PatKind::Wild, &PatKind::Wild) => true,
334 #[allow(clippy::similar_names)]
335 fn eq_qpath(&mut self, left: &QPath<'_>, right: &QPath<'_>) -> bool {
336 match (left, right) {
337 (&QPath::Resolved(ref lty, ref lpath), &QPath::Resolved(ref rty, ref rpath)) => {
338 both(lty, rty, |l, r| self.eq_ty(l, r)) && self.eq_path(lpath, rpath)
340 (&QPath::TypeRelative(ref lty, ref lseg), &QPath::TypeRelative(ref rty, ref rseg)) => {
341 self.eq_ty(lty, rty) && self.eq_path_segment(lseg, rseg)
343 (&QPath::LangItem(llang_item, _), &QPath::LangItem(rlang_item, _)) => llang_item == rlang_item,
348 fn eq_path(&mut self, left: &Path<'_>, right: &Path<'_>) -> bool {
349 match (left.res, right.res) {
350 (Res::Local(l), Res::Local(r)) => l == r || self.locals.get(&l) == Some(&r),
351 (Res::Local(_), _) | (_, Res::Local(_)) => false,
352 _ => over(&left.segments, &right.segments, |l, r| self.eq_path_segment(l, r)),
356 fn eq_path_parameters(&mut self, left: &GenericArgs<'_>, right: &GenericArgs<'_>) -> bool {
357 if !(left.parenthesized || right.parenthesized) {
358 over(&left.args, &right.args, |l, r| self.eq_generic_arg(l, r)) // FIXME(flip1995): may not work
359 && over(&left.bindings, &right.bindings, |l, r| self.eq_type_binding(l, r))
360 } else if left.parenthesized && right.parenthesized {
361 over(left.inputs(), right.inputs(), |l, r| self.eq_ty(l, r))
362 && both(&Some(&left.bindings[0].ty()), &Some(&right.bindings[0].ty()), |l, r| {
370 pub fn eq_path_segments(&mut self, left: &[PathSegment<'_>], right: &[PathSegment<'_>]) -> bool {
371 left.len() == right.len() && left.iter().zip(right).all(|(l, r)| self.eq_path_segment(l, r))
374 pub fn eq_path_segment(&mut self, left: &PathSegment<'_>, right: &PathSegment<'_>) -> bool {
375 // The == of idents doesn't work with different contexts,
376 // we have to be explicit about hygiene
377 left.ident.name == right.ident.name && both(&left.args, &right.args, |l, r| self.eq_path_parameters(l, r))
380 fn eq_ty(&mut self, left: &Ty<'_>, right: &Ty<'_>) -> bool {
381 self.eq_ty_kind(&left.kind, &right.kind)
384 #[allow(clippy::similar_names)]
385 fn eq_ty_kind(&mut self, left: &TyKind<'_>, right: &TyKind<'_>) -> bool {
386 match (left, right) {
387 (&TyKind::Slice(ref l_vec), &TyKind::Slice(ref r_vec)) => self.eq_ty(l_vec, r_vec),
388 (&TyKind::Array(ref lt, ref ll_id), &TyKind::Array(ref rt, ref rl_id)) => {
389 let cx = self.inner.cx;
391 |body| constant_context(cx, cx.tcx.typeck_body(body)).expr(&cx.tcx.hir().body(body).value);
392 self.eq_ty(lt, rt) && eval_const(ll_id.body) == eval_const(rl_id.body)
394 (&TyKind::Ptr(ref l_mut), &TyKind::Ptr(ref r_mut)) => {
395 l_mut.mutbl == r_mut.mutbl && self.eq_ty(&*l_mut.ty, &*r_mut.ty)
397 (&TyKind::Rptr(_, ref l_rmut), &TyKind::Rptr(_, ref r_rmut)) => {
398 l_rmut.mutbl == r_rmut.mutbl && self.eq_ty(&*l_rmut.ty, &*r_rmut.ty)
400 (&TyKind::Path(ref l), &TyKind::Path(ref r)) => self.eq_qpath(l, r),
401 (&TyKind::Tup(ref l), &TyKind::Tup(ref r)) => over(l, r, |l, r| self.eq_ty(l, r)),
402 (&TyKind::Infer, &TyKind::Infer) => true,
407 fn eq_type_binding(&mut self, left: &TypeBinding<'_>, right: &TypeBinding<'_>) -> bool {
408 left.ident.name == right.ident.name && self.eq_ty(&left.ty(), &right.ty())
412 /// Some simple reductions like `{ return }` => `return`
413 fn reduce_exprkind<'hir>(cx: &LateContext<'_>, kind: &'hir ExprKind<'hir>) -> &'hir ExprKind<'hir> {
414 if let ExprKind::Block(block, _) = kind {
415 match (block.stmts, block.expr) {
416 // From an `if let` expression without an `else` block. The arm for the implicit wild pattern is an empty
417 // block with an empty span.
418 ([], None) if block.span.is_empty() => &ExprKind::Tup(&[]),
420 ([], None) => match snippet_opt(cx, block.span) {
421 // Don't reduce if there are any tokens contained in the braces
428 TokenKind::LineComment { .. } | TokenKind::BlockComment { .. } | TokenKind::Whitespace
431 .ne([TokenKind::OpenBrace, TokenKind::CloseBrace].iter().cloned()) =>
435 _ => &ExprKind::Tup(&[]),
437 ([], Some(expr)) => match expr.kind {
438 // `{ return .. }` => `return ..`
439 ExprKind::Ret(..) => &expr.kind,
442 ([stmt], None) => match stmt.kind {
443 StmtKind::Expr(expr) | StmtKind::Semi(expr) => match expr.kind {
444 // `{ return ..; }` => `return ..`
445 ExprKind::Ret(..) => &expr.kind,
461 ) -> Option<(BinOpKind, &'a Expr<'a>, &'a Expr<'a>)> {
463 BinOpKind::Add | BinOpKind::Eq | BinOpKind::Ne | BinOpKind::BitAnd | BinOpKind::BitXor | BinOpKind::BitOr => {
464 Some((binop, rhs, lhs))
466 BinOpKind::Lt => Some((BinOpKind::Gt, rhs, lhs)),
467 BinOpKind::Le => Some((BinOpKind::Ge, rhs, lhs)),
468 BinOpKind::Ge => Some((BinOpKind::Le, rhs, lhs)),
469 BinOpKind::Gt => Some((BinOpKind::Lt, rhs, lhs)),
470 BinOpKind::Mul // Not always commutative, e.g. with matrices. See issue #5698
477 | BinOpKind::Or => None,
481 /// Checks if the two `Option`s are both `None` or some equal values as per
483 pub fn both<X>(l: &Option<X>, r: &Option<X>, mut eq_fn: impl FnMut(&X, &X) -> bool) -> bool {
485 .map_or_else(|| r.is_none(), |x| r.as_ref().map_or(false, |y| eq_fn(x, y)))
488 /// Checks if two slices are equal as per `eq_fn`.
489 pub fn over<X>(left: &[X], right: &[X], mut eq_fn: impl FnMut(&X, &X) -> bool) -> bool {
490 left.len() == right.len() && left.iter().zip(right).all(|(x, y)| eq_fn(x, y))
493 /// Checks if two expressions evaluate to the same value, and don't contain any side effects.
494 pub fn eq_expr_value(cx: &LateContext<'_>, left: &Expr<'_>, right: &Expr<'_>) -> bool {
495 SpanlessEq::new(cx).deny_side_effects().eq_expr(left, right)
498 /// Type used to hash an ast element. This is different from the `Hash` trait
499 /// on ast types as this
500 /// trait would consider IDs and spans.
502 /// All expressions kind are hashed, but some might have a weaker hash.
503 pub struct SpanlessHash<'a, 'tcx> {
504 /// Context used to evaluate constant expressions.
505 cx: &'a LateContext<'tcx>,
506 maybe_typeck_results: Option<&'tcx TypeckResults<'tcx>>,
510 impl<'a, 'tcx> SpanlessHash<'a, 'tcx> {
511 pub fn new(cx: &'a LateContext<'tcx>) -> Self {
514 maybe_typeck_results: cx.maybe_typeck_results(),
515 s: StableHasher::new(),
519 pub fn finish(self) -> u64 {
523 pub fn hash_block(&mut self, b: &Block<'_>) {
528 if let Some(ref e) = b.expr {
533 BlockCheckMode::DefaultBlock => 0,
534 BlockCheckMode::UnsafeBlock(_) => 1,
535 BlockCheckMode::PushUnsafeBlock(_) => 2,
536 BlockCheckMode::PopUnsafeBlock(_) => 3,
541 #[allow(clippy::many_single_char_names, clippy::too_many_lines)]
542 pub fn hash_expr(&mut self, e: &Expr<'_>) {
543 let simple_const = self
544 .maybe_typeck_results
545 .and_then(|typeck_results| constant_simple(self.cx, typeck_results, e));
547 // const hashing may result in the same hash as some unrelated node, so add a sort of
548 // discriminant depending on which path we're choosing next
549 simple_const.is_some().hash(&mut self.s);
551 if let Some(e) = simple_const {
552 return e.hash(&mut self.s);
555 std::mem::discriminant(&e.kind).hash(&mut self.s);
558 ExprKind::AddrOf(kind, m, ref e) => {
560 BorrowKind::Ref => 0,
561 BorrowKind::Raw => 1,
567 ExprKind::Continue(i) => {
568 if let Some(i) = i.label {
569 self.hash_name(i.ident.name);
572 ExprKind::Assign(ref l, ref r, _) => {
576 ExprKind::AssignOp(ref o, ref l, ref r) => {
578 .hash_stable(&mut self.cx.tcx.get_stable_hashing_context(), &mut self.s);
582 ExprKind::Block(ref b, _) => {
585 ExprKind::Binary(op, ref l, ref r) => {
587 .hash_stable(&mut self.cx.tcx.get_stable_hashing_context(), &mut self.s);
591 ExprKind::Break(i, ref j) => {
592 if let Some(i) = i.label {
593 self.hash_name(i.ident.name);
595 if let Some(ref j) = *j {
599 ExprKind::Box(ref e) | ExprKind::DropTemps(ref e) | ExprKind::Yield(ref e, _) => {
602 ExprKind::Call(ref fun, args) => {
604 self.hash_exprs(args);
606 ExprKind::Cast(ref e, ref ty) | ExprKind::Type(ref e, ref ty) => {
610 ExprKind::Closure(cap, _, eid, _, _) => {
612 CaptureBy::Value => 0,
616 // closures inherit TypeckResults
617 self.hash_expr(&self.cx.tcx.hir().body(eid).value);
619 ExprKind::Field(ref e, ref f) => {
621 self.hash_name(f.name);
623 ExprKind::Index(ref a, ref i) => {
627 ExprKind::InlineAsm(ref asm) => {
628 for piece in asm.template {
630 InlineAsmTemplatePiece::String(s) => s.hash(&mut self.s),
631 InlineAsmTemplatePiece::Placeholder {
636 operand_idx.hash(&mut self.s);
637 modifier.hash(&mut self.s);
641 asm.options.hash(&mut self.s);
642 for (op, _op_sp) in asm.operands {
644 InlineAsmOperand::In { reg, expr } => {
645 reg.hash(&mut self.s);
646 self.hash_expr(expr);
648 InlineAsmOperand::Out { reg, late, expr } => {
649 reg.hash(&mut self.s);
650 late.hash(&mut self.s);
651 if let Some(expr) = expr {
652 self.hash_expr(expr);
655 InlineAsmOperand::InOut { reg, late, expr } => {
656 reg.hash(&mut self.s);
657 late.hash(&mut self.s);
658 self.hash_expr(expr);
660 InlineAsmOperand::SplitInOut {
666 reg.hash(&mut self.s);
667 late.hash(&mut self.s);
668 self.hash_expr(in_expr);
669 if let Some(out_expr) = out_expr {
670 self.hash_expr(out_expr);
673 InlineAsmOperand::Const { expr } | InlineAsmOperand::Sym { expr } => self.hash_expr(expr),
677 ExprKind::LlvmInlineAsm(..) | ExprKind::Err => {},
678 ExprKind::Lit(ref l) => {
679 l.node.hash(&mut self.s);
681 ExprKind::Loop(ref b, ref i, ..) => {
683 if let Some(i) = *i {
684 self.hash_name(i.ident.name);
687 ExprKind::If(ref cond, ref then, ref else_opt) => {
688 let c: fn(_, _, _) -> _ = ExprKind::If;
690 self.hash_expr(cond);
691 self.hash_expr(&**then);
692 if let Some(ref e) = *else_opt {
696 ExprKind::Match(ref e, arms, ref s) => {
701 if let Some(ref e) = arm.guard {
704 self.hash_expr(&arm.body);
709 ExprKind::MethodCall(ref path, ref _tys, args, ref _fn_span) => {
710 self.hash_name(path.ident.name);
711 self.hash_exprs(args);
713 ExprKind::ConstBlock(ref l_id) => {
714 self.hash_body(l_id.body);
716 ExprKind::Repeat(ref e, ref l_id) => {
718 self.hash_body(l_id.body);
720 ExprKind::Ret(ref e) => {
721 if let Some(ref e) = *e {
725 ExprKind::Path(ref qpath) => {
726 self.hash_qpath(qpath);
728 ExprKind::Struct(ref path, fields, ref expr) => {
729 self.hash_qpath(path);
732 self.hash_name(f.ident.name);
733 self.hash_expr(&f.expr);
736 if let Some(ref e) = *expr {
740 ExprKind::Tup(tup) => {
741 self.hash_exprs(tup);
743 ExprKind::Array(v) => {
746 ExprKind::Unary(lop, ref le) => {
747 lop.hash_stable(&mut self.cx.tcx.get_stable_hashing_context(), &mut self.s);
753 pub fn hash_exprs(&mut self, e: &[Expr<'_>]) {
759 pub fn hash_name(&mut self, n: Symbol) {
760 n.as_str().hash(&mut self.s);
763 pub fn hash_qpath(&mut self, p: &QPath<'_>) {
765 QPath::Resolved(_, ref path) => {
766 self.hash_path(path);
768 QPath::TypeRelative(_, ref path) => {
769 self.hash_name(path.ident.name);
771 QPath::LangItem(lang_item, ..) => {
772 lang_item.hash_stable(&mut self.cx.tcx.get_stable_hashing_context(), &mut self.s);
775 // self.maybe_typeck_results.unwrap().qpath_res(p, id).hash(&mut self.s);
778 pub fn hash_path(&mut self, path: &Path<'_>) {
780 // constant hash since equality is dependant on inter-expression context
781 Res::Local(_) => 1_usize.hash(&mut self.s),
783 for seg in path.segments {
784 self.hash_name(seg.ident.name);
790 pub fn hash_stmt(&mut self, b: &Stmt<'_>) {
791 std::mem::discriminant(&b.kind).hash(&mut self.s);
794 StmtKind::Local(local) => {
795 if let Some(ref init) = local.init {
796 self.hash_expr(init);
799 StmtKind::Item(..) => {},
800 StmtKind::Expr(expr) | StmtKind::Semi(expr) => {
801 self.hash_expr(expr);
806 pub fn hash_guard(&mut self, g: &Guard<'_>) {
808 Guard::If(ref expr) | Guard::IfLet(_, ref expr) => {
809 self.hash_expr(expr);
814 pub fn hash_lifetime(&mut self, lifetime: &Lifetime) {
815 std::mem::discriminant(&lifetime.name).hash(&mut self.s);
816 if let LifetimeName::Param(ref name) = lifetime.name {
817 std::mem::discriminant(name).hash(&mut self.s);
819 ParamName::Plain(ref ident) => {
820 ident.name.hash(&mut self.s);
822 ParamName::Fresh(ref size) => {
823 size.hash(&mut self.s);
825 ParamName::Error => {},
830 pub fn hash_ty(&mut self, ty: &Ty<'_>) {
831 self.hash_tykind(&ty.kind);
834 pub fn hash_tykind(&mut self, ty: &TyKind<'_>) {
835 std::mem::discriminant(ty).hash(&mut self.s);
837 TyKind::Slice(ty) => {
840 TyKind::Array(ty, anon_const) => {
842 self.hash_body(anon_const.body);
844 TyKind::Ptr(mut_ty) => {
845 self.hash_ty(&mut_ty.ty);
846 mut_ty.mutbl.hash(&mut self.s);
848 TyKind::Rptr(lifetime, mut_ty) => {
849 self.hash_lifetime(lifetime);
850 self.hash_ty(&mut_ty.ty);
851 mut_ty.mutbl.hash(&mut self.s);
853 TyKind::BareFn(bfn) => {
854 bfn.unsafety.hash(&mut self.s);
855 bfn.abi.hash(&mut self.s);
856 for arg in bfn.decl.inputs {
859 match bfn.decl.output {
860 FnRetTy::DefaultReturn(_) => {
861 ().hash(&mut self.s);
863 FnRetTy::Return(ref ty) => {
867 bfn.decl.c_variadic.hash(&mut self.s);
869 TyKind::Tup(ty_list) => {
874 TyKind::Path(qpath) => match qpath {
875 QPath::Resolved(ref maybe_ty, ref path) => {
876 if let Some(ref ty) = maybe_ty {
879 for segment in path.segments {
880 segment.ident.name.hash(&mut self.s);
881 self.hash_generic_args(segment.args().args);
884 QPath::TypeRelative(ref ty, ref segment) => {
886 segment.ident.name.hash(&mut self.s);
888 QPath::LangItem(lang_item, ..) => {
889 lang_item.hash(&mut self.s);
892 TyKind::OpaqueDef(_, arg_list) => {
893 self.hash_generic_args(arg_list);
895 TyKind::TraitObject(_, lifetime, _) => {
896 self.hash_lifetime(lifetime);
898 TyKind::Typeof(anon_const) => {
899 self.hash_body(anon_const.body);
901 TyKind::Err | TyKind::Infer | TyKind::Never => {},
905 pub fn hash_body(&mut self, body_id: BodyId) {
906 // swap out TypeckResults when hashing a body
907 let old_maybe_typeck_results = self.maybe_typeck_results.replace(self.cx.tcx.typeck_body(body_id));
908 self.hash_expr(&self.cx.tcx.hir().body(body_id).value);
909 self.maybe_typeck_results = old_maybe_typeck_results;
912 fn hash_generic_args(&mut self, arg_list: &[GenericArg<'_>]) {
913 for arg in arg_list {
915 GenericArg::Lifetime(ref l) => self.hash_lifetime(l),
916 GenericArg::Type(ref ty) => self.hash_ty(&ty),
917 GenericArg::Const(ref ca) => self.hash_body(ca.value.body),