RequirementMachine: Remove no-longer used DebugFlags::Merge

Author: slavapestov

lib/AST/RequirementMachine/Debug.h

@@ -26,45 +26,42 @@ enum class DebugFlags : unsigned {
   /// Print debug output when adding rules.
   Add = (1<<1),
 
-  /// Print debug output when merging associated types.
-  Merge = (1<<2),
-
   /// Print debug output from the Knuth-Bendix algorithm.
-  Completion = (1<<3),
+  Completion = (1<<2),
 
   /// Print debug output from property map construction.
-  PropertyMap = (1<<4),
+  PropertyMap = (1<<3),
 
   /// Print debug output when unifying concrete types in the property map.
-  ConcreteUnification = (1<<5),
+  ConcreteUnification = (1<<4),
 
   /// Print debug output when concretizing nested types in the property map.
-  ConcretizeNestedTypes = (1<<6),
+  ConcretizeNestedTypes = (1<<5),
 
   /// Print debug output when inferring conditional requirements in the
   /// property map.
-  ConditionalRequirements = (1<<7),
+  ConditionalRequirements = (1<<6),
 
   /// Print debug output from the homotopy reduction algorithm.
-  HomotopyReduction = (1<<8),
+  HomotopyReduction = (1<<7),
 
   /// Print more detailed debug output from the homotopy reduction algorithm.
-  HomotopyReductionDetail = (1<<9),
+  HomotopyReductionDetail = (1<<8),
 
   /// Print debug output from the minimal conformances algorithm.
-  MinimalConformances = (1<<10),
+  MinimalConformances = (1<<9),
 
   /// Print debug output from the protocol dependency graph.
-  ProtocolDependencies = (1<<11),
+  ProtocolDependencies = (1<<10),
 
   /// Print debug output from generic signature minimization.
-  Minimization = (1<<12),
+  Minimization = (1<<11),
 
   /// Print redundant rules and their replacement paths.
-  RedundantRules = (1<<13),
+  RedundantRules = (1<<12),
 
   /// Print more detail about redundant rules.
-  RedundantRulesDetail = (1<<14)
+  RedundantRulesDetail = (1<<13)
 };
 
 using DebugOptions = OptionSet<DebugFlags>;

lib/AST/RequirementMachine/RewriteContext.cpp

@@ -29,7 +29,6 @@ static DebugOptions parseDebugFlags(StringRef debugFlags) {
     auto flag = llvm::StringSwitch<Optional<DebugFlags>>(flagStr)
       .Case("simplify", DebugFlags::Simplify)
       .Case("add", DebugFlags::Add)
-      .Case("merge", DebugFlags::Merge)
       .Case("completion", DebugFlags::Completion)
       .Case("property-map", DebugFlags::PropertyMap)
       .Case("concrete-unification", DebugFlags::ConcreteUnification)