[PATCH] D81627: [HIP] Do not call opt/llc for -fno-gpu-rdc

[Artem Belevich via Phabricator via cfe-commits]

tra added a comment.

Looks OK in general. I'm happy to see reduced opt/llc use.

You may want to get someone more familiar with the AMD GPU compilation process to double-check that the compilation pipeline still does the right thing.



================
Comment at: clang/lib/Driver/Driver.cpp:2725-2726
         for (unsigned I = 0, E = GpuArchList.size(); I != E; ++I) {
           // Create a link action to link device IR with device library
           // and generate ISA.
+          CudaDeviceActions[I] = C.getDriver().ConstructPhaseAction(
----------------
The comment about "create link action" should probably be moved down below to where the link action is constructed now.



================
Comment at: clang/lib/Driver/Driver.cpp:2727-2732
+          CudaDeviceActions[I] = C.getDriver().ConstructPhaseAction(
+              C, Args, phases::Backend, CudaDeviceActions[I],
+              AssociatedOffloadKind);
+          CudaDeviceActions[I] = C.getDriver().ConstructPhaseAction(
+              C, Args, phases::Assemble, CudaDeviceActions[I],
+              AssociatedOffloadKind);
----------------
Looks like we're chaining backend/assembly actions here. but it's not easy to spot that we use `CudaDeviceActions[I]`  as an intermediate value. At the first glance it looked like a copy/paste error writing to `CudaDeviceActions[I]` multiple times.

It would be easier to see what's going on if the code was structured like this:
```
BackendAction = Construct(... CudaDeviceActions[I]);
AssembleAction  = Construct(... BackendAction);
AL.push_back(AssembleAction)
CudaDeviceActions[I] = C.MakeAction<LinkJobAction>(AL);
```



CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D81627/new/

https://reviews.llvm.org/D81627