[clang] [Clang][OpenCL][AMDGPU] Allow a kernel to call another kernel (PR #115821)

[Aniket Lal via cfe-commits]

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@@ -71,14 +71,19 @@ class GlobalDecl {
   GlobalDecl(const FunctionDecl *D, unsigned MVIndex = 0)
       : MultiVersionIndex(MVIndex) {
     if (!D->hasAttr<CUDAGlobalAttr>()) {
+      if (D->hasAttr<OpenCLKernelAttr>()) {
+        Value.setPointerAndInt(D, unsigned(KernelReferenceKind::Kernel));
+        return;
+      }
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lalaniket8 wrote:

Added `isReferenceableKernel()` to `FunctionDecl`. Since OpenCL does not support template kernel functions, I have not added it to `FunctionTemplateDecl`.

https://github.com/llvm/llvm-project/pull/115821