[analyzer] [NFC] remove duplicated function

Two copies of getSymLERange in RangeConstraintManager are virtually
identical, which is clearly bad.
This patch uses lambdas to call one from another (assuming that we would
like to avoid getting ranges from the state when necessary).

Differential Revision: https://reviews.llvm.org/D39709

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@319697 91177308-0d34-0410-b5e6-96231b3b80d8

lib/StaticAnalyzer/Core/RangeConstraintManager.cpp

@@ -354,7 +354,8 @@ private:
   RangeSet getSymLERange(ProgramStateRef St, SymbolRef Sym,
                          const llvm::APSInt &Int,
                          const llvm::APSInt &Adjustment);
-  RangeSet getSymLERange(const RangeSet &RS, const llvm::APSInt &Int,
+  RangeSet getSymLERange(llvm::function_ref<RangeSet()> RS,
+                         const llvm::APSInt &Int,
                          const llvm::APSInt &Adjustment);
   RangeSet getSymGERange(ProgramStateRef St, SymbolRef Sym,
                          const llvm::APSInt &Int,
@@ -685,9 +686,10 @@ RangeConstraintManager::assumeSymGE(ProgramStateRef St, SymbolRef Sym,
   return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
 }
 
-RangeSet RangeConstraintManager::getSymLERange(const RangeSet &RS,
-                                               const llvm::APSInt &Int,
-                                               const llvm::APSInt &Adjustment) {
+RangeSet RangeConstraintManager::getSymLERange(
+      llvm::function_ref<RangeSet()> RS,
+      const llvm::APSInt &Int,
+      const llvm::APSInt &Adjustment) {
   // Before we do any real work, see if the value can even show up.
   APSIntType AdjustmentType(Adjustment);
   switch (AdjustmentType.testInRange(Int, true)) {
@@ -696,48 +698,27 @@ RangeSet RangeConstraintManager::getSymLERange(const RangeSet &RS,
   case APSIntType::RTR_Within:
     break;
   case APSIntType::RTR_Above:
-    return RS;
+    return RS();
   }
 
   // Special case for Int == Max. This is always feasible.
   llvm::APSInt ComparisonVal = AdjustmentType.convert(Int);
   llvm::APSInt Max = AdjustmentType.getMaxValue();
   if (ComparisonVal == Max)
-    return RS;
+    return RS();
 
   llvm::APSInt Min = AdjustmentType.getMinValue();
   llvm::APSInt Lower = Min - Adjustment;
   llvm::APSInt Upper = ComparisonVal - Adjustment;
 
-  return RS.Intersect(getBasicVals(), F, Lower, Upper);
+  return RS().Intersect(getBasicVals(), F, Lower, Upper);
 }
 
 RangeSet RangeConstraintManager::getSymLERange(ProgramStateRef St,
                                                SymbolRef Sym,
                                                const llvm::APSInt &Int,
                                                const llvm::APSInt &Adjustment) {
-  // Before we do any real work, see if the value can even show up.
-  APSIntType AdjustmentType(Adjustment);
-  switch (AdjustmentType.testInRange(Int, true)) {
-  case APSIntType::RTR_Below:
-    return F.getEmptySet();
-  case APSIntType::RTR_Within:
-    break;
-  case APSIntType::RTR_Above:
-    return getRange(St, Sym);
-  }
-
-  // Special case for Int == Max. This is always feasible.
-  llvm::APSInt ComparisonVal = AdjustmentType.convert(Int);
-  llvm::APSInt Max = AdjustmentType.getMaxValue();
-  if (ComparisonVal == Max)
-    return getRange(St, Sym);
-
-  llvm::APSInt Min = AdjustmentType.getMinValue();
-  llvm::APSInt Lower = Min - Adjustment;
-  llvm::APSInt Upper = ComparisonVal - Adjustment;
-
-  return getRange(St, Sym).Intersect(getBasicVals(), F, Lower, Upper);
+  return getSymLERange([&] { return getRange(St, Sym); }, Int, Adjustment);
 }
 
 ProgramStateRef
@@ -754,8 +735,8 @@ ProgramStateRef RangeConstraintManager::assumeSymWithinInclusiveRange(
   RangeSet New = getSymGERange(State, Sym, From, Adjustment);
   if (New.isEmpty())
     return nullptr;
-  New = getSymLERange(New, To, Adjustment);
-  return New.isEmpty() ? nullptr : State->set<ConstraintRange>(Sym, New);
+  RangeSet Out = getSymLERange([&] { return New; }, To, Adjustment);
+  return Out.isEmpty() ? nullptr : State->set<ConstraintRange>(Sym, Out);
 }
 
 ProgramStateRef RangeConstraintManager::assumeSymOutsideInclusiveRange(