[clang] [OpenACC] Implement 'firstprivate' clause copy lowering (PR #154150)

[Andy Kaylor via cfe-commits]

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@@ -392,12 +392,27 @@ class OpenACCClauseCIREmitter final
       CIRGenFunction::AutoVarEmission tempDeclEmission,
       mlir::acc::FirstprivateRecipeOp recipe, const VarDecl *varRecipe,
       const VarDecl *temporary) {
-    builder.createBlock(&recipe.getCopyRegion(), recipe.getCopyRegion().end(),
-                        {mainOp.getType(), mainOp.getType()}, {loc, loc});
+    mlir::Block *block = builder.createBlock(
+        &recipe.getCopyRegion(), recipe.getCopyRegion().end(),
+        {mainOp.getType(), mainOp.getType()}, {loc, loc});
     builder.setInsertionPointToEnd(&recipe.getCopyRegion().back());
 
-    // TODO: OpenACC: Implement this copy to actually do something.
+    mlir::BlockArgument fromArg = block->getArgument(0);
+    mlir::BlockArgument toArg = block->getArgument(1);
+
+    mlir::Type elementTy =
+        mlir::cast<cir::PointerType>(mainOp.getType()).getPointee();
+
+    // Set the address of the emission to be the argument, so that we initialize
+    // that instead of the variable in the other block.
+    tempDeclEmission.setAllocatedAddress(
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andykaylor wrote:

Where is the memory for this actually allocated? Does that happen during lowering to some other dialect?

https://github.com/llvm/llvm-project/pull/154150