[clang] [llvm] [DataLayout] Introduce sentinel pointer value (PR #131557)

[Shilei Tian via llvm-commits]

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@@ -32,9 +32,9 @@ static const char *const DataLayoutStringR600 =
     "-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64-S32-A5-G1";
 
 static const char *const DataLayoutStringAMDGCN =
-    "e-p:64:64-p1:64:64-p2:32:32-p3:32:32-p4:64:64-p5:32:32-p6:32:32"
-    "-p7:160:256:256:32-p8:128:128-p9:192:256:256:32-i64:64-v16:16-v24:32-v32:"
-    "32-v48:64-v96:128"
+    "e-p:64:64-p1:64:64-p2:32:32-p3:32:32:32:32:f-p4:64:64-p5:32:32:32:32:f"
+    "-p6:32:32-p7:160:256:256:32-p8:128:128-p9:192:256:256:32-i64:64-v16:16"
+    "-v24:32-v32:32-v48:64-v96:128"
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shiltian wrote:

Right, that's why I didn't try to add that information to the fat pointer at the moment, and it is all-zero anyway.

https://github.com/llvm/llvm-project/pull/131557