commit 3d56a22775f4dfd949a574f929440e9bd2e54f7f
author Dani Ferreira Franco Moura <danimoura@google.com> Tue Nov 29 03:12:55 2022 -0800
committer Copybara-Service <copybara-worker@google.com> Tue Nov 29 03:13:30 2022 -0800
tree e5dbebaf7d5260f7ac2e94399d452d6570577cb1
parent a90de3d6ffe10d291d7d3fe844a20889472204bd

Create pointer nullability lattice.

We hope to make use of the Clang Dataflow Analysis framework to propagate nullability annotations (for example, on assignment of template-instantiated values). For this, we will alter the lattice used in pointer nullability analysis to contain maps from expressions and variable declarations to nullability annotations. This change introduces a custom lattice to the pointer nullability analysis. This lattice is still undistinguishable from a NoopLattice (we will add more functionality on a subsequent change).

PiperOrigin-RevId: 491586319

nullability_verification/pointer_nullability_analysis.h

diff --git a/nullability_verification/pointer_nullability_analysis.h b/nullability_verification/pointer_nullability_analysis.h
index 3ff9ac0..4515091 100644
--- a/nullability_verification/pointer_nullability_analysis.h
+++ b/nullability_verification/pointer_nullability_analysis.h
@@ -5,12 +5,12 @@
 #ifndef CRUBIT_NULLABILITY_VERIFICATION_POINTER_NULLABILITY_ANALYSIS_H_
 #define CRUBIT_NULLABILITY_VERIFICATION_POINTER_NULLABILITY_ANALYSIS_H_
 
+#include "nullability_verification/pointer_nullability_lattice.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/Type.h"
 #include "clang/Analysis/FlowSensitive/CFGMatchSwitch.h"
 #include "clang/Analysis/FlowSensitive/DataflowAnalysis.h"
 #include "clang/Analysis/FlowSensitive/DataflowEnvironment.h"
-#include "clang/Analysis/FlowSensitive/NoopLattice.h"
 #include "clang/Analysis/FlowSensitive/Value.h"
 
 namespace clang {
@@ -21,13 +21,13 @@
 /// about pointers at each program point.
 class PointerNullabilityAnalysis
     : public dataflow::DataflowAnalysis<PointerNullabilityAnalysis,
-                                        dataflow::NoopLattice> {
+                                        PointerNullabilityLattice> {
  public:
   explicit PointerNullabilityAnalysis(ASTContext& context);
 
-  static dataflow::NoopLattice initialElement() { return {}; }
+  static PointerNullabilityLattice initialElement() { return {}; }
 
-  void transfer(const CFGElement* Elt, dataflow::NoopLattice& Lattice,
+  void transfer(const CFGElement* Elt, PointerNullabilityLattice& Lattice,
                 dataflow::Environment& Env);
 
   bool merge(QualType Type, const dataflow::Value& Val1,
@@ -37,7 +37,7 @@
 
  private:
   // Applies transfer functions on statements
-  dataflow::CFGMatchSwitch<dataflow::TransferState<dataflow::NoopLattice>>
+  dataflow::CFGMatchSwitch<dataflow::TransferState<PointerNullabilityLattice>>
       Transferer;
 };
 }  // namespace nullability