[clang] [Driver][NVPTX] Add a warning that device debug info does not work with optimizations (PR #65327)

[Artem Belevich via cfe-commits]

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@@ -28,6 +28,17 @@
 // RUN:   --offload-arch=sm_35 --cuda-path=%S/Inputs/CUDA/usr/local/cuda \
 // RUN: | FileCheck -check-prefixes=CHECK,ARCH64,SM35,RDC %s
 
+// Compiling -O{1,2,3,4,fast,s,z} with -g does not pass -g debug info to ptxas.
+// NOTE: This is because ptxas does not support optimized debugging.
+// RUN: %clang -### --target=x86_64-linux-gnu -O3 -g -c %s 2>&1 \
+// RUN:   --offload-arch=sm_35 --cuda-path=%S/Inputs/CUDA/usr/local/cuda \
+// RUN: | FileCheck -check-prefixes=CHECK,ARCH64,SM35,OPT3-DBG %s
+
+// Compiling -O0 with -g passes -g debug info to ptxas.
+// RUN: %clang -### --target=x86_64-linux-gnu -O0 -g -c %s 2>&1 \
+// RUN:   --offload-arch=sm_35 --cuda-path=%S/Inputs/CUDA/usr/local/cuda \
+// RUN: | FileCheck -check-prefixes=CHECK,ARCH64,SM35,OPT0-DBG %s
+
 // With debugging enabled, ptxas should be run with with no ptxas optimizations.
 // RUN: %clang -### --target=x86_64-linux-gnu --cuda-noopt-device-debug -O2 -g -c %s 2>&1 \
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Artem-B wrote:

We should have a test for the warning, so we're sure we're not spamming users with something they can't do much about.

https://github.com/llvm/llvm-project/pull/65327