8fe11a26ae
This patch adds support for lowering OpenMP clauses and expressions attached to constructs nested inside of a target region that need to be evaluated in the host device. This is done through the use of the `OpenMP_HostEvalClause` `omp.target` set of operands and entry block arguments. When lowering clauses for a target construct, a more involved `processHostEvalClauses()` function is called, which looks at the current and potentially other nested constructs in order to find and lower clauses that need to be processed outside of the `omp.target` operation under construction. This populates an instance of a global structure with the resulting MLIR values. The resulting list of host-evaluated values is used to initialize the `host_eval` operands when constructing the `omp.target` operation, and then replaced with the corresponding block arguments after creating that operation's region. Afterwards, while lowering nested operations, those that might potentially be evaluated on the host (i.e. `num_teams`, `thread_limit`, `num_threads` and `collapse`) check first whether there is an active global host-evaluated information structure and whether it holds values referring to these clauses. If that is the case, the stored values (`omp.target` entry block arguments at that stage) are used instead of lowering these clauses again.
1.9 KiB
1.9 KiB