[clang] Reland "[HIP] Use original file path for CUID" (#108771) (PR #111885)

[Artem Belevich via cfe-commits]

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@@ -1,13 +1,15 @@
 // Check CUID generated by hash.
 // The same CUID is generated for the same file with the same options.
 
+// RUN: cd %S
+
 // RUN: %clang -### -x hip --target=x86_64-unknown-linux-gnu --no-offload-new-driver \
 // RUN:   --offload-arch=gfx906 -c -nogpuinc -nogpulib -fuse-cuid=hash \
-// RUN:   %S/Inputs/hip_multiple_inputs/a.cu >%t.out 2>&1
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Artem-B wrote:

This does not change the fact that "Inputs/hip_multiple_inputs/a.cu" simply may not be there when the test runs.

E.g. we're executing the tests remotely and the source tree lives in a completely different location compared to the tests. Without "%S" pointing lit there clang will not be able to find the file.

https://github.com/llvm/llvm-project/pull/111885