[clang] Revert "Revert "[AMDGPU] const-fold imm operands of (PR #71669)

[Matt Arsenault via cfe-commits]

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@@ -0,0 +1,48 @@
+// REQUIRES: amdgpu-registered-target
+
+// RUN: %clang --offload-arch=gfx906 -S -o - -emit-llvm --cuda-device-only -nogpuinc -nogpulib\
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arsenm wrote:

This should use %clang_cc1, look at some of the other CodeGen* test run lines for examples 

https://github.com/llvm/llvm-project/pull/71669