dnrops
/
rust
mirror of https://github.com/rust-lang/rust.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Move paren expr and loop HIR lowering

This commit is contained in:
Gary Guo 2022-12-02 17:44:05 +00:00
parent 0c0fb226bb
commit 6275b045d7
1 changed files with 37 additions and 28 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

65
compiler/rustc_ast_lowering/src/expr.rs
View File

@ -31,6 +31,41 @@ impl<'hir> LoweringContext<'_, 'hir> {
pub(super) fn lower_expr_mut(&mut self, e: &Expr) -> hir::Expr<'hir> {
ensure_sufficient_stack(|| {
match &e.kind {
// Paranthesis expression does not have a HirId and is handled specially.
ExprKind::Paren(ex) => {
let mut ex = self.lower_expr_mut(ex);
// Include parens in span, but only if it is a super-span.
if e.span.contains(ex.span) {
ex.span = self.lower_span(e.span);
}
// Merge attributes into the inner expression.
if !e.attrs.is_empty() {
let old_attrs =
self.attrs.get(&ex.hir_id.local_id).map(|la| *la).unwrap_or(&[]);
self.attrs.insert(
ex.hir_id.local_id,
&*self.arena.alloc_from_iter(
e.attrs
.iter()
.map(|a| self.lower_attr(a))
.chain(old_attrs.iter().cloned()),
),
);
}
return ex;
}
// Desugar `ExprForLoop`
// from: `[opt_ident]: for <pat> in <head> <body>`
//
// This also needs special handling because the HirId of the returned `hir::Expr` will not
// correspond to the `e.id`, so `lower_expr_for` handles attribute lowering itself.
ExprKind::ForLoop(pat, head, body, opt_label) => {
return self.lower_expr_for(e, pat, head, body, *opt_label);
}
_ => (),
}
let hir_id = self.lower_node_id(e.id);
self.lower_attrs(hir_id, &e.attrs);
@ -51,7 +86,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
if e.attrs.get(0).map_or(false, |a| a.has_name(sym::rustc_box)) {
if let [inner] = &args[..] && e.attrs.len() == 1 {
let kind = hir::ExprKind::Box(self.lower_expr(&inner));
let hir_id = self.lower_node_id(e.id);
return hir::Expr { hir_id, kind, span: self.lower_span(e.span) };
} else {
self.tcx.sess.emit_err(RustcBoxAttributeError { span: e.span });
@ -283,34 +317,9 @@ impl<'hir> LoweringContext<'_, 'hir> {
ExprKind::Yield(opt_expr) => self.lower_expr_yield(e.span, opt_expr.as_deref()),
ExprKind::Err => hir::ExprKind::Err,
ExprKind::Try(sub_expr) => self.lower_expr_try(e.span, sub_expr),
ExprKind::Paren(ex) => {
let mut ex = self.lower_expr_mut(ex);
// Include parens in span, but only if it is a super-span.
if e.span.contains(ex.span) {
ex.span = self.lower_span(e.span);
}
// Merge attributes into the inner expression.
if !e.attrs.is_empty() {
let old_attrs =
self.attrs.get(&ex.hir_id.local_id).map(|la| *la).unwrap_or(&[]);
self.attrs.insert(
ex.hir_id.local_id,
&*self.arena.alloc_from_iter(
e.attrs
.iter()
.map(|a| self.lower_attr(a))
.chain(old_attrs.iter().cloned()),
),
);
}
return ex;
}
// Desugar `ExprForLoop`
// from: `[opt_ident]: for <pat> in <head> <body>`
ExprKind::ForLoop(pat, head, body, opt_label) => {
return self.lower_expr_for(e, pat, head, body, *opt_label);
}
ExprKind::Paren(_) | ExprKind::ForLoop(..) => unreachable!("already handled"),
ExprKind::MacCall(_) => panic!("{:?} shouldn't exist here", e.span),
};