[clang] [OpenACC][CIR] Implement 'init' lowering for private clause vars (PR #151781)

[Erich Keane via cfe-commits]

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@@ -837,23 +837,43 @@ class OpenACCClauseWithVarList : public OpenACCClauseWithExprs {
 
 class OpenACCPrivateClause final
     : public OpenACCClauseWithVarList,
-      private llvm::TrailingObjects<OpenACCPrivateClause, Expr *> {
+      private llvm::TrailingObjects<OpenACCPrivateClause, Expr *, VarDecl *> {
   friend TrailingObjects;
 
   OpenACCPrivateClause(SourceLocation BeginLoc, SourceLocation LParenLoc,
-                       ArrayRef<Expr *> VarList, SourceLocation EndLoc)
+                       ArrayRef<Expr *> VarList,
+                       ArrayRef<VarDecl *> InitRecipes, SourceLocation EndLoc)
       : OpenACCClauseWithVarList(OpenACCClauseKind::Private, BeginLoc,
                                  LParenLoc, EndLoc) {
-    setExprs(getTrailingObjects(VarList.size()), VarList);
+    assert(VarList.size() == InitRecipes.size());
+    setExprs(getTrailingObjects<Expr *>(VarList.size()), VarList);
+    llvm::uninitialized_copy(InitRecipes, getTrailingObjects<VarDecl *>());
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erichkeane wrote:

`std::initialized_copy` doesn't take the range, so I'd have to write out `InitRecipes.begin(), InitRecipes.end()`.  The LLVM versions are 'whole range' versions that simplify the code.

https://github.com/llvm/llvm-project/pull/151781