[clang] [libclc] [libclc] Enable 64-bit atomics for nvptx64 (PR #213691)

[Zheming Jin via cfe-commits]

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@@ -159,6 +159,13 @@ class LLVM_LIBRARY_VISIBILITY NVPTXTargetInfo : public TargetInfo {
     Opts["cl_khr_global_int32_extended_atomics"] = true;
     Opts["cl_khr_local_int32_base_atomics"] = true;
     Opts["cl_khr_local_int32_extended_atomics"] = true;
+    // 64-bit atomics are supported natively on 64-bit targets, where
+    // MaxAtomicInlineWidth is the target pointer width. libclc needs these
+    // extensions enabled to define the 64-bit atomic builtins.
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zjin-lcf wrote:

Agreed, dropped the whole comment.

https://github.com/llvm/llvm-project/pull/213691