type_ir: add faster exit for types_may_unify

davidtwco · davidtwco · commit febb16a40fe2 · 2025-05-13T16:47:10.000Z
diff --git a/compiler/rustc_type_ir/src/fast_reject.rs b/compiler/rustc_type_ir/src/fast_reject.rs
@@ -232,6 +232,9 @@ impl<I: Interner, const INSTANTIATE_LHS_WITH_INFER: bool, const INSTANTIATE_RHS_
     }
 
     pub fn types_may_unify(self, lhs: I::Ty, rhs: I::Ty) -> bool {
+        if lhs == rhs {
+            return true;
+        }
         self.types_may_unify_inner(lhs, rhs, Self::STARTING_DEPTH)
     }
 

Original file line number	Diff line number	Diff line change
`@@ -232,6 +232,9 @@ impl<I: Interner, const INSTANTIATE_LHS_WITH_INFER: bool, const INSTANTIATE_RHS_`
`232`	`232`	`}`
`233`	`233`
`234`	`234`	`pub fn types_may_unify(self, lhs: I::Ty, rhs: I::Ty) -> bool {`
	`235`	`+ if lhs == rhs {`
	`236`	`+ return true;`
	`237`	`+ }`
`235`	`238`	`self.types_may_unify_inner(lhs, rhs, Self::STARTING_DEPTH)`
`236`	`239`	`}`
`237`	`240`