Auto merge of #142802 - compiler-errors:dedup-analyses, r=lcnr

Collapse Analysis|Borrowck|PostBorrowckAnalysis when there are no opaques

r? lcnr

Author: bors

compiler/rustc_type_ir/src/infer_ctxt.rs

@@ -117,12 +117,20 @@ impl<I: Interner> TypingMode<I> {
     }
 
     pub fn borrowck(cx: I, body_def_id: I::LocalDefId) -> TypingMode<I> {
-        TypingMode::Borrowck { defining_opaque_types: cx.opaque_types_defined_by(body_def_id) }
+        let defining_opaque_types = cx.opaque_types_defined_by(body_def_id);
+        if defining_opaque_types.is_empty() {
+            TypingMode::non_body_analysis()
+        } else {
+            TypingMode::Borrowck { defining_opaque_types }
+        }
     }
 
     pub fn post_borrowck_analysis(cx: I, body_def_id: I::LocalDefId) -> TypingMode<I> {
-        TypingMode::PostBorrowckAnalysis {
-            defined_opaque_types: cx.opaque_types_defined_by(body_def_id),
+        let defined_opaque_types = cx.opaque_types_defined_by(body_def_id);
+        if defined_opaque_types.is_empty() {
+            TypingMode::non_body_analysis()
+        } else {
+            TypingMode::PostBorrowckAnalysis { defined_opaque_types }
         }
     }
 }