[clang] [clang][dataflow] Discard unneeded `ExprToLoc` and `ExprToVal` entries. (PR #72850)

[Yitzhak Mandelbaum via cfe-commits]

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@@ -24,25 +24,35 @@
 namespace clang {
 namespace dataflow {
 
-/// Returns a map from statements to basic blocks that contain them.
-static llvm::DenseMap<const Stmt *, const CFGBlock *>
-buildStmtToBasicBlockMap(const CFG &Cfg) {
-  llvm::DenseMap<const Stmt *, const CFGBlock *> StmtToBlock;
+/// Builds maps:
+/// - From statements to basic blocks that contain them.
+/// - From blocks to the expressions they consume.
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ymand wrote:

Is the term "consume" defined somewhere?

https://github.com/llvm/llvm-project/pull/72850