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| Value count = | ||
| LLVM::LoadOp::create(rewriter, op.getLoc(), type_i32, host_count_ptr) | ||
| .getResult(); | ||
| Value datatype = | ||
| LLVM::LoadOp::create(rewriter, op.getLoc(), type_nccl_datatype, | ||
| host_datatype_ptr) | ||
| .getResult(); | ||
| Value redop = LLVM::LoadOp::create(rewriter, op.getLoc(), type_nccl_redop, | ||
| host_redop_ptr) | ||
| .getResult(); | ||
| Value comm = | ||
| LLVM::LoadOp::create(rewriter, op.getLoc(), type_ptr, host_comm_ptr) | ||
| .getResult(); |
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This seems pretty unfortunate: allocate a buffer on the device, only to immediately copy it back to the host in the jit wrapper? But maybe this is the best we can do given xla constraints?
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we should be able to avoid this memcpys by using attributes, but i don't know yet how to do it with jit_call. i think it's fine for now and can be improved once we learn how to pass attributes with jit_call.
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You need this for proper jit lowering
the device pointer TODO: the same change needs to be made for ncclSend/Recv/etc
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i've skipped the implementation of some ops that we may not need right now (
ncclCommSplit,ncclCommDestroy, ...).waiting for #3100 to be merged first (or fuse both PRs into one)
to do