[OpenMP][MLIR] Hoist static allocas emitted by private init regions to the allocation IP of the construct
#915
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…ns to the allocation IP of the construct Having more than 1 descritpr (allocatable or array) on the same `private` clause triggers a runtime crash on GPUs at the moment. For SPMD kernels, the issue happens because the initialization logic includes: * Allocating a number of temporary structs (these are emitted by flang when `fir` is lowered to `mlir.llvm`). * There is a conditional branch that determines whether we will allocate storage for the descriptor and initialize array bounds from the original descriptor or whether we will initialize the private descriptor to null. Because of these 2 things, temp allocations needed for descriptors beyond the 1st one are preceded by branching which causes the observed the runtime crash. This PR solves this issue by hoisting these static `alloca`s instructions to the suitable allca IP of the parent construct.
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Upstream PR was already merged. Closing this test PR. |
This is not for merging, it tests the changes of the upstream PR: llvm#171597 on our internal CI.
Having more than 1 descritpr (allocatable or array) on the same
privateclause triggers a runtime crash on GPUs at the moment.For SPMD kernels, the issue happens because the initialization logic includes:
firis lowered tomlir.llvm).Because of these 2 things, temp allocations needed for descriptors beyond the 1st one are preceded by branching which causes the observed the runtime crash.
This PR solves this issue by hoisting these static
allocas instructions to the suitable allca IP of the parent construct.