[clang][dataflow] Add `create<T>()` methods to `Environment` and `DataflowAnalysisContext`.

These methods provide a less verbose way of allocating `StorageLocation`s and
`Value`s than the existing `takeOwnership(make_unique(...))` pattern.

In addition, because allocation of `StorageLocation`s and `Value`s now happens
within the `DataflowAnalysisContext`, the `create<T>()` open up the possibility
of using `BumpPtrAllocator` to allocate these objects if it turns out this
helps performance.

Reviewed By: ymandel, xazax.hun, gribozavr2

Differential Revision: https://reviews.llvm.org/D147302

1 files changed, 5 insertions, 6 deletions

diff --git a/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp b/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp
index fbb8d8a..faeabdc 100644
--- a/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp
+++ b/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp
@@ -359,7 +359,7 @@ void Environment::pushCallInternal(const FunctionDecl *FuncDecl,
 
     QualType ParamType = Param->getType();
     if (ParamType->isReferenceType()) {
-      auto &Val = takeOwnership(std::make_unique<ReferenceValue>(*ArgLoc));
+      auto &Val = create<ReferenceValue>(*ArgLoc);
       setValue(Loc, Val);
     } else if (auto *ArgVal = getValue(*ArgLoc)) {
       setValue(Loc, *ArgVal);
@@ -685,7 +685,7 @@ Value *Environment::createValueUnlessSelfReferential(
     // with integers, and so distinguishing them serves no purpose, but could
     // prevent convergence.
     CreatedValuesCount++;
-    return &takeOwnership(std::make_unique<IntegerValue>());
+    return &create<IntegerValue>();
   }
 
   if (Type->isReferenceType()) {
@@ -702,7 +702,7 @@ Value *Environment::createValueUnlessSelfReferential(
         setValue(PointeeLoc, *PointeeVal);
     }
 
-    return &takeOwnership(std::make_unique<ReferenceValue>(PointeeLoc));
+    return &create<ReferenceValue>(PointeeLoc);
   }
 
   if (Type->isPointerType()) {
@@ -719,7 +719,7 @@ Value *Environment::createValueUnlessSelfReferential(
         setValue(PointeeLoc, *PointeeVal);
     }
 
-    return &takeOwnership(std::make_unique<PointerValue>(PointeeLoc));
+    return &create<PointerValue>(PointeeLoc);
   }
 
   if (Type->isStructureOrClassType() || Type->isUnionType()) {
@@ -739,8 +739,7 @@ Value *Environment::createValueUnlessSelfReferential(
       Visited.erase(FieldType.getCanonicalType());
     }
 
-    return &takeOwnership(
-        std::make_unique<StructValue>(std::move(FieldValues)));
+    return &create<StructValue>(std::move(FieldValues));
   }
 
   return nullptr;