Simplify base_expr

sanxiyn · oli-obk · web-flow · commit 899aae465eb4 · 2021-01-29T01:44:15.000+09:00
Co-authored-by: Oli Scherer &lt;github35764891676564198441@oli-obk.de&gt;
diff --git a/compiler/rustc_passes/src/dead.rs b/compiler/rustc_passes/src/dead.rs
@@ -37,17 +37,13 @@ fn should_explore(tcx: TyCtxt<'_>, hir_id: hir::HirId) -> bool {
     )
 }
 
-fn base_expr<'a>(expr: &'a hir::Expr<'a>) -> &'a hir::Expr<'a> {
-    let mut current = expr;
+fn base_expr<'a>(mut expr: &'a hir::Expr<'a>) -> &'a hir::Expr<'a>
     loop {
-        match current.kind {
-            hir::ExprKind::Field(base, ..) => {
-                current = base;
-            }
-            _ => break,
+        match expr.kind {
+            hir::ExprKind::Field(base, ..) => expr = base,
+            _ => return expr,
         }
     }
-    current
 }
 
 struct MarkSymbolVisitor<'tcx> {

Original file line number	Diff line number	Diff line change
`@@ -37,17 +37,13 @@ fn should_explore(tcx: TyCtxt<'_>, hir_id: hir::HirId) -> bool {`
`37`	`37`	`)`
`38`	`38`	`}`
`39`	`39`
`40`		`-fn base_expr<'a>(expr: &'a hir::Expr<'a>) -> &'a hir::Expr<'a> {`
`41`		`- let mut current = expr;`
	`40`	`+fn base_expr<'a>(mut expr: &'a hir::Expr<'a>) -> &'a hir::Expr<'a>`
`42`	`41`	`loop {`
`43`		`- match current.kind {`
`44`		`- hir::ExprKind::Field(base, ..) => {`
`45`		`- current = base;`
`46`		`- }`
`47`		`- _ => break,`
	`42`	`+ match expr.kind {`
	`43`	`+ hir::ExprKind::Field(base, ..) => expr = base,`
	`44`	`+ _ => return expr,`
`48`	`45`	`}`
`49`	`46`	`}`
`50`		`- current`
`51`	`47`	`}`
`52`	`48`
`53`	`49`	`struct MarkSymbolVisitor<'tcx> {`