Merge pull request #83439 from xedin/allow-debugging-of-decl-specialization-comparison

[CSRanking] Pass down a flag to enable debug output in `CompareDeclSp…

Author: xedin

include/swift/AST/TypeCheckRequests.h

@@ -2883,7 +2883,7 @@ class SynthesizeDefaultInitRequest
 class CompareDeclSpecializationRequest
     : public SimpleRequest<CompareDeclSpecializationRequest,
                            bool(DeclContext *, ValueDecl *, ValueDecl *, bool,
-                                bool),
+                                bool, bool),
                            RequestFlags::Cached> {
 public:
   using SimpleRequest::SimpleRequest;
@@ -2893,8 +2893,8 @@ class CompareDeclSpecializationRequest
 
   // Evaluation.
   bool evaluate(Evaluator &evaluator, DeclContext *DC, ValueDecl *VD1,
-                ValueDecl *VD2, bool dynamic,
-                bool allowMissingConformances) const;
+                ValueDecl *VD2, bool dynamic, bool allowMissingConformances,
+                bool debugMode) const;
 
 public:
   // Caching.

include/swift/AST/TypeCheckerTypeIDZone.def

@@ -52,7 +52,7 @@ SWIFT_REQUEST(TypeChecker, CheckRedeclarationRequest,
 SWIFT_REQUEST(TypeChecker, ClassAncestryFlagsRequest,
               AncestryFlags(ClassDecl *), Cached, NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, CompareDeclSpecializationRequest,
-              bool (DeclContext *, ValueDecl *, ValueDecl *, bool, bool),
+              bool (DeclContext *, ValueDecl *, ValueDecl *, bool, bool, bool),
               Cached, NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, ConditionalRequirementsRequest,
               ArrayRef<Requirement> (NormalProtocolConformance *),

lib/Sema/CSRanking.cpp

@@ -465,20 +465,25 @@ static bool paramIsIUO(const ValueDecl *decl, int paramNum) {
 static bool isDeclAsSpecializedAs(DeclContext *dc, ValueDecl *decl1,
                                   ValueDecl *decl2,
                                   bool isDynamicOverloadComparison = false,
-                                  bool allowMissingConformances = true) {
+                                  bool allowMissingConformances = true,
+                                  bool debugMode = false) {
   return evaluateOrDefault(decl1->getASTContext().evaluator,
                            CompareDeclSpecializationRequest{
                                dc, decl1, decl2, isDynamicOverloadComparison,
-                               allowMissingConformances},
+                               allowMissingConformances, debugMode},
                            false);
 }
 
 bool CompareDeclSpecializationRequest::evaluate(
     Evaluator &eval, DeclContext *dc, ValueDecl *decl1, ValueDecl *decl2,
-    bool isDynamicOverloadComparison, bool allowMissingConformances) const {
+    bool isDynamicOverloadComparison, bool allowMissingConformances,
+    bool debugMode) const {
   auto &C = decl1->getASTContext();
+  ConstraintSystemOptions options;
+  if (debugMode)
+    options |= ConstraintSystemFlags::DebugConstraints;
   // Construct a constraint system to compare the two declarations.
-  ConstraintSystem cs(dc, ConstraintSystemOptions());
+  ConstraintSystem cs(dc, options);
   if (cs.isDebugMode()) {
     llvm::errs() << "Comparing declarations\n";
     decl1->print(llvm::errs());
@@ -1174,15 +1179,15 @@ SolutionCompareResult ConstraintSystem::compareSolutions(
     // Determine whether one declaration is more specialized than the other.
     bool firstAsSpecializedAs = false;
     bool secondAsSpecializedAs = false;
-    if (isDeclAsSpecializedAs(cs.DC, decl1, decl2,
-                              isDynamicOverloadComparison,
-                              /*allowMissingConformances=*/false)) {
+    if (isDeclAsSpecializedAs(cs.DC, decl1, decl2, isDynamicOverloadComparison,
+                              /*allowMissingConformances=*/false,
+                              cs.isDebugMode())) {
       score1 += weight;
       firstAsSpecializedAs = true;
     }
-    if (isDeclAsSpecializedAs(cs.DC, decl2, decl1,
-                              isDynamicOverloadComparison,
-                              /*allowMissingConformances=*/false)) {
+    if (isDeclAsSpecializedAs(cs.DC, decl2, decl1, isDynamicOverloadComparison,
+                              /*allowMissingConformances=*/false,
+                              cs.isDebugMode())) {
       score2 += weight;
       secondAsSpecializedAs = true;
     }