Remove shouldDiscardFailures() from ConstraintLocator,

remove shouldRecordFailures() from ConstraintSystem.  NFC.

Author: lattner

lib/Sema/CSDiag.cpp

@@ -4997,13 +4997,14 @@ bool ConstraintSystem::salvage(SmallVectorImpl<Solution> &viable, Expr *expr) {
   // Attempt to solve again, capturing all states that come from our attempts to
   // select overloads or bind type variables.
   //
-  // FIXME: can this be removed??
+  // FIXME: can this be removed?  We need to arrange for recordFixes to be
+  // eliminated.
   viable.clear();
 
   {
     // Set up solver state.
     SolverState state(*this);
-    state.recordFailures = true;
+    state.recordFixes = true;
     this->solverState = &state;
 
     // Solve the system.

lib/Sema/ConstraintLocator.h

@@ -449,17 +449,6 @@ class ConstraintLocator : public llvm::FoldingSetNode {
     Profile(id, anchor, getPath());
   }
 
-  /// \brief Determine whether or not constraint failures associated with this
-  /// locator should be discarded.
-  bool shouldDiscardFailures() {
-    return discardFailures;
-  }
-  
-  /// \brief Toggle option to discard constraint failures.
-  void setDiscardFailures(bool shouldDiscard = true) {
-    discardFailures = shouldDiscard;
-  }
-
   /// \brief Produce a debugging dump of this locator.
   LLVM_ATTRIBUTE_DEPRECATED(
       void dump(SourceManager *SM) LLVM_ATTRIBUTE_USED,
@@ -474,8 +463,7 @@ class ConstraintLocator : public llvm::FoldingSetNode {
   /// \brief Initialize a constraint locator with an anchor and a path.
   ConstraintLocator(Expr *anchor, ArrayRef<PathElement> path,
                     unsigned flags)
-    : anchor(anchor), numPathElements(path.size()), summaryFlags(flags),
-      discardFailures(false)
+    : anchor(anchor), numPathElements(path.size()), summaryFlags(flags)
   {
     // FIXME: Alignment.
     std::copy(path.begin(), path.end(),
@@ -510,11 +498,6 @@ class ConstraintLocator : public llvm::FoldingSetNode {
   /// \brief A set of flags summarizing interesting properties of the path.
   unsigned summaryFlags : 7;
 
-  /// \brief Determines whether or not we should record constraint application
-  /// failures associated with this locator. This information cannot be
-  /// inferred from the path itself, so it is not stored as a summary flag.
-  unsigned discardFailures: 1;
-
   friend class ConstraintSystem;
 };
 

lib/Sema/ConstraintSystem.h

@@ -998,7 +998,7 @@ class ConstraintSystem {
     unsigned depth = 0;
 
     /// \brief Whether to record failures or not.
-    bool recordFailures = false;
+    bool recordFixes = false;
 
     /// The list of constraints that have been retired along the
     /// current path.
@@ -1265,23 +1265,13 @@ class ConstraintSystem {
   getConstraintLocator(const ConstraintLocatorBuilder &builder);
 
 public:
-  /// \brief Whether we should be recording failures.
-  bool shouldRecordFailures() {
-    // FIXME: It still makes sense to record failures when there are fixes
-    // present, but they should be less desirable.
-    if (!Fixes.empty())
-      return false;
-
-    return !solverState || solverState->recordFailures ||
-           TC.Context.LangOpts.DebugConstraintSolver;
-  }
 
   /// \brief Whether we should attempt to fix problems.
   bool shouldAttemptFixes() {
     if (!(Options & ConstraintSystemFlags::AllowFixes))
       return false;
 
-    return !solverState || solverState->recordFailures;
+    return !solverState || solverState->recordFixes;
   }
 
   /// \brief Log and record the application of the fix. Return true iff any