[PATCH] D123773: [clang][analyzer][ctu] Make CTU a two phase analysis

[Gabor Marton via Phabricator via cfe-commits]

martong added inline comments.


================
Comment at: clang/include/clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h:116
 
+  const bool Foreign = false; // From CTU.
+
----------------
martong wrote:
> xazax.hun wrote:
> > I feel that we use different terms for the imported declarations. Sometimes we call them `new`, sometimes `imported`, sometimes `foreign`. In case all of these means the same thing, it would be nice to standardize on a single way of naming. If there is a subtle difference between them, let's document that in a comment. It would be nice if we did not need the comment after the declaration but it would be obvious from the variable name.
> Yes, I agree that this should deserver some more explanation. Maybe right above this declaration?
> 
> So, `new` means that a declaration is **created** newly by the ASTImporter.
> `imported` means it has been imported, but not necessarily `new`. Think about this case, we import `foo`'s definition.
> ```
> // to.cpp
> void bar() {} // from a.h
> // from.cpp
> void bar() {} // from a.h
> void foo() {
>   bar();
> }
> ```
> Then `foo` will be `new` and `imported`, `bar` will be `imported` and not `new`.  
> `foreign` basically means `imported` and `new`.
I've just added an explanatory comment for this field.


================
Comment at: clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp:432
+
+bool ExprEngine::ctuBifurcate(const CallEvent &Call, const Decl *D,
+                              NodeBuilder &Bldr, ExplodedNode *Pred,
----------------
martong wrote:
> xazax.hun wrote:
> > What is the meaning if the return value? It looks like the function always returns true.
> Nothing. It is being used by `inlineCall` but there are no callers of `inlineCall` that would use it because `inlineCall` does return true on all paths as well. Good point, this is again a rotten legacy. I am going update this soon.
I've changed the return value from bool to void, both in `ctuBifurcate` and in `inlineCall`.


================
Comment at: clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp:516
+  // function in the main TU.
+  if (Engine.getCTUWorkList())
+    // Mark the decl as visited.
----------------
martong wrote:
> xazax.hun wrote:
> > So `getCTUWorkList` will return `nullptr` in the second phase? Reading this code first I had the impression we will skip doing marking them visited in the first phase. I think having a helper like `IsSecondCTUPhase` or something would make this a bit less confusing.
> Fair enough. I am going to update.
I've added `isCTUInFirtstPhase()`.


================
Comment at: clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp:1130
       // We are not bifurcating and we do have a Decl, so just inline.
-      if (inlineCall(*Call, D, Bldr, Pred, State))
+      if (ctuBifurcate(*Call, D, Bldr, Pred, State))
         return;
----------------
martong wrote:
> xazax.hun wrote:
> > I think this is getting really confusing here. The comment saying we are not bifurcating and we call `ctuBifurcate`. While I do understand these are two different kinds of bifurcation but I think we should rethink how to name some of these functions. 
> Yeah, good point, the comment is meaningless and confusing from this point, I'll just delete it.
I removed the comment.


Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D123773/new/

https://reviews.llvm.org/D123773