=?utf-8?q?Kristóf?= Umann <dkszelet...@gmail.com>,
=?utf-8?q?Kristóf?= Umann <dkszelet...@gmail.com>,
=?utf-8?q?Kristóf?= Umann <dkszelet...@gmail.com>,
=?utf-8?q?Kristóf?= Umann <dkszelet...@gmail.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/97...@github.com>
================
@@ -346,6 +350,36 @@ class CompoundVal : public NonLoc {
static bool classof(SVal V) { return V.getKind() == CompoundValKind; }
};
+/// While nonloc::CompoundVal covers a few simple use cases,
+/// nonloc::LazyCompoundVal is a more performant and flexible way to represent
+/// an rvalue of record type, so it shows up much more frequently during
+/// analysis. This value is an r-value that represents a snapshot of any
+/// structure "as a whole" at a given moment during the analysis. Such value is
+/// already quite far from being referred to as "concrete", as many fields
+/// inside it would be unknown or symbolic. nonloc::LazyCompoundVal operates by
+/// storing two things:
+/// * a reference to the TypedValueRegion being snapshotted (yes, it is
always
+/// typed), and also
+/// * a reference to the whole Store object, obtained from the ProgramState in
+/// which the nonloc::LazyCompoundVal was created.
+///
+/// Note that the old ProgramState and its Store is kept alive during the
+/// analysis because these are immutable functional data structures and each
new
+/// Store value is represented as "earlier Store" + "additional binding".
+///
+/// Essentially, nonloc::LazyCompoundVal is a performance optimization for the
+/// analyzer. Because Store is immutable, creating a nonloc::LazyCompoundVal is
+/// a very cheap operation. Note that the Store contains all region bindings in
+/// the program state, not only related to the region. Later, if necessary,
such
+/// value can be unpacked -- eg. when it is assigned to another variable.
+///
+/// If you ever need inspect the contents of the LazyCompoundVal, you can use
----------------
steakhal wrote:
```suggestion
/// If you ever need to inspect the contents of the LazyCompoundVal, you can use
```
https://github.com/llvm/llvm-project/pull/97407
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
