[clang] [llvm] [NVPTX] Update data layout string to include null pointer value spec (PR #195178)

[Artem Belevich via cfe-commits]

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@@ -144,11 +144,11 @@
 
 // RUN: %clang_cc1 -triple nvptx-unknown -o - -emit-llvm %s | \
 // RUN: FileCheck %s -check-prefix=NVPTX
-// NVPTX: target datalayout = "e-p:32:32-p6:32:32-p7:32:32-i64:64-i128:128-i256:256-v16:16-v32:32-n16:32:64"
+// NVPTX: target datalayout = "e-p:32:32-po3:32:32-po5:32:32-p6:32:32-po7:32:32-i64:64-i128:128-i256:256-v16:16-v32:32-n16:32:64"
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Artem-B wrote:

@gonzalobg @AlexMaclean Any thoughts on what kind of nullptr makes sense for particular AS on NVIDIA GPUs?

https://github.com/llvm/llvm-project/pull/195178