[clang] [NVPTX][AMDGPU][CodeGen] Fix `local_space nullptr` handling for NVPTX and local/private `nullptr` value for AMDGPU. (PR #78759)

[Matt Arsenault via cfe-commits]

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@@ -418,8 +418,10 @@ class LLVM_LIBRARY_VISIBILITY AMDGPUTargetInfo final : public TargetInfo {
   // value ~0.
   uint64_t getNullPointerValue(LangAS AS) const override {
     // FIXME: Also should handle region.
-    return (AS == LangAS::opencl_local || AS == LangAS::opencl_private)
-      ? ~0 : 0;
+    return (AS == LangAS::opencl_local || AS == LangAS::opencl_private ||
+            AS == LangAS::sycl_local || AS == LangAS::sycl_private)
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arsenm wrote:

Is there a point to having separate LangAS enums for these? 

https://github.com/llvm/llvm-project/pull/78759