[PATCH] D38134: [OpenCL] Emit enqueued block as kernel

[Yaxun Liu via Phabricator via cfe-commits]

yaxunl marked 10 inline comments as done.
yaxunl added a comment.

In https://reviews.llvm.org/D38134#880133, @Anastasia wrote:

> I think we should add a test case when the same block is both called and enqueued.


Will do.



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Comment at: test/CodeGenOpenCL/amdgpu-enqueue-kernel.cl:3
+
+// CHECK: %[[S1:struct.__amdgpu_block_arg_t.*]] = type { [3 x i64], [1 x i8] }
+// CHECK: %[[S2:struct.__amdgpu_block_arg_t.*]] = type { [5 x i64], [1 x i8] }
----------------
Anastasia wrote:
> yaxunl wrote:
> > Anastasia wrote:
> > > This struct is not identical to block literal struct?
> > The LLVM type of the first argument of block invoke function is created directly with sorting and rearrangement. There is no AST type corresponding to it. However, the function codegen requires AST type of this argument. I feel it is unnecessary to create the corresponding AST type. For simplicity, just create an AST type with the same size and alignment as the LLVM type. In the function code, it will be bitcasted to the correct LLVM struct type and get the captured variables.
> So `void ptr` won't be possible here? Since it is cast to a right struct inside the block anyway. Once again a block is a special type object with known semantic to compiler and runtime in contract to kernels that can be written with any arbitrary type of arguments.
> 
> I just don't like the idea of duplicating the block invoke function in case it's being both called and enqueued. Also the login in blocks code generation becomes difficult to understand. So I am wondering if we could perhaps create a separate kernel function (as a wrapper) for enqueue_kernel which would call a block instead. What do you think about it? I think the kernel prototype would be fairly generic as it would just have a block call inside and pass the arguments into it... We won't need to modify block generation then at all. 
Will emit a wrapper kernel which calls the block invoke function and keep the block invoke function unchanged.


https://reviews.llvm.org/D38134