[llvm] [AMDGPU] Improve detection of non-null addrspacecast operands (PR #82311)

[Matt Arsenault via llvm-commits]

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@@ -51,6 +51,12 @@ static cl::opt<bool> Widen16BitOps(
   cl::ReallyHidden,
   cl::init(true));
 
+static cl::opt<bool> LowerAddrSpaceCast(
+    "amdgpu-codegenprepare-addrspacecast",
+    cl::desc("Detect non-null addrspacecast source and lower them early to "
+             "avoid the null pointer check"),
+    cl::ReallyHidden, cl::init(true));
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arsenm wrote:

Don't really need an option 

https://github.com/llvm/llvm-project/pull/82311