RequirementMachine: Improved verifyMinimizedRules()

Author: slavapestov

lib/AST/RequirementMachine/HomotopyReduction.cpp

@@ -543,7 +543,7 @@ void RewriteSystem::minimizeRewriteSystem() {
   // Check invariants after homotopy reduction.
   verifyRewriteLoops();
   verifyRedundantConformances(redundantConformances);
-  verifyMinimizedRules();
+  verifyMinimizedRules(redundantConformances);
 }
 
 /// In a conformance-valid rewrite system, any rule with unresolved symbols on
@@ -656,7 +656,7 @@ void RewriteSystem::verifyRewriteLoops() const {
 /// Assert if homotopy reduction failed to eliminate a redundant conformance,
 /// since this suggests a misunderstanding on my part.
 void RewriteSystem::verifyRedundantConformances(
-    llvm::DenseSet<unsigned> redundantConformances) const {
+    const llvm::DenseSet<unsigned> &redundantConformances) const {
 #ifndef NDEBUG
   for (unsigned ruleID : redundantConformances) {
     const auto &rule = getRule(ruleID);
@@ -680,9 +680,12 @@ void RewriteSystem::verifyRedundantConformances(
 
 // Assert if homotopy reduction failed to eliminate a rewrite rule it was
 // supposed to delete.
-void RewriteSystem::verifyMinimizedRules() const {
+void RewriteSystem::verifyMinimizedRules(
+    const llvm::DenseSet<unsigned> &redundantConformances) const {
 #ifndef NDEBUG
-  for (const auto &rule : Rules) {
+  for (unsigned ruleID : indices(Rules)) {
+    const auto &rule = getRule(ruleID);
+
     // Note that sometimes permanent rules can be simplified, but they can never
     // be redundant.
     if (rule.isPermanent()) {
@@ -706,6 +709,15 @@ void RewriteSystem::verifyMinimizedRules() const {
       dump(llvm::errs());
       abort();
     }
+
+    if (rule.isRedundant() &&
+        rule.isAnyConformanceRule() &&
+        !rule.containsUnresolvedSymbols() &&
+        !redundantConformances.count(ruleID)) {
+      llvm::errs() << "Minimal conformance is redundant: " << rule << "\n\n";
+      dump(llvm::errs());
+      abort();
+    }
   }
 #endif
 }

lib/AST/RequirementMachine/MinimalConformances.cpp

@@ -903,15 +903,8 @@ void MinimalConformances::verifyMinimalConformances() const {
       continue;
     }
 
-    if (rule.isRedundant()) {
-      llvm::errs() << "Generating conformance is redundant: ";
-      llvm::errs() << rule << "\n\n";
-      dumpMinimalConformanceEquations(llvm::errs());
-      abort();
-    }
-
     if (rule.getLHS().containsUnresolvedSymbols()) {
-      llvm::errs() << "Generating conformance contains unresolved symbols: ";
+      llvm::errs() << "Minimal conformance contains unresolved symbols: ";
       llvm::errs() << rule << "\n\n";
       dumpMinimalConformanceEquations(llvm::errs());
       abort();
@@ -922,7 +915,7 @@ void MinimalConformances::verifyMinimalConformances() const {
 
 void MinimalConformances::dumpMinimalConformances(
     llvm::raw_ostream &out) const {
-  out << "Generating conformances:\n";
+  out << "Minimal conformances:\n";
 
   for (const auto &pair : ConformancePaths) {
     if (RedundantConformances.count(pair.first) > 0)

lib/AST/RequirementMachine/RewriteSystem.h

@@ -461,9 +461,10 @@ class RewriteSystem final {
   void verifyRewriteLoops() const;
 
   void verifyRedundantConformances(
-      llvm::DenseSet<unsigned> redundantConformances) const;
+      const llvm::DenseSet<unsigned> &redundantConformances) const;
 
-  void verifyMinimizedRules() const;
+  void verifyMinimizedRules(
+      const llvm::DenseSet<unsigned> &redundantConformances) const;
 
 public:
   void dump(llvm::raw_ostream &out) const;