[clang] [lld] [llvm] [mlir] [IR] Introduce `T<address space>` to `DataLayout` to represent flat address space if a target supports it (PR #108786)

[Shilei Tian via cfe-commits]

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@@ -66,12 +66,12 @@ NVPTXTargetInfo::NVPTXTargetInfo(const llvm::Triple &Triple,
   HasFloat16 = true;
 
   if (TargetPointerWidth == 32)
-    resetDataLayout("e-p:32:32-i64:64-i128:128-v16:16-v32:32-n16:32:64");
+    resetDataLayout("e-p:32:32-i64:64-i128:128-v16:16-v32:32-n16:32:64-T0");
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shiltian wrote:

@Artem-B can you check if this is correct for NVPTX?

https://github.com/llvm/llvm-project/pull/108786