https://github.com/AlexVlx commented:
> > > We added sema check @ > > > https://github.com/llvm/llvm-project/blob/8378a6fa4f5c83298fb0b5e240bb7f254f7b1137/clang/lib/Sema/SemaCUDA.cpp#L83 > > > to generate error message on HIP based on Sam's request as HIP currently > > > doesnt' support device-side kernel calls. I don't follow how we could > > > have `CUDAKernelCallExpr` in the device compilation. Could you elaborate > > > in details? > > > > The sema check doesn't work as is for `hipstdpar`, because it's gated on > > the current target being either a `__global__` function or a `__device__` > > function. What happens is that we do the parsing on a normal function, the > > <<<>>> expression is semantically valid, and then we try to > > `EmitCUDAKernelCallExpr`, because at CodeGen that is gated on whether the > > entire compilation is host or device, not on whether or not the caller is > > `__global__` or `__device__`. So either the latter check should actually > > establish the caller's context, or we should bypass this altogether when > > compiling for hipstdpar. This is the simplest NFC workaround to unbreak > > things. > > Why not add `getLangOpts().HIPStdPar` check in sema to skip generating > device-side kernel call? So that we have a central place to make that > decision? Because, as far as I can ascertain, the `Sema` check is insufficient / the separate assert in `EmitCUDAKernelCallExpr` is disjoint. Here's what would happen: 1. In Sema what we see is that `IsDeviceKernelCall` is false - this is fine, but we still would emit a `CudaKernelCallExpr` for the `<<<>>>` callsite, which was the case anyways before this change; 2. Later on, when we get to `CodeGen`, we see the `CudaKernelCallExpr`, and try to handle it, except now the assumption is that if we're compiling for device and we see that, it must be a device side launch, and go look up a non-existent symbol, and run into the bug. https://github.com/llvm/llvm-project/pull/171043 _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
