[clang] Implement `ByteAddressBuffer` Load/Store methods (PR #176058)

[Sarah Spall via cfe-commits]

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@@ -432,6 +432,9 @@ Value *CodeGenFunction::EmitHLSLBuiltinExpr(unsigned BuiltinID,
 
     if (RT->getAttrs().RawBuffer) {
       Value *Offset = Builder.getInt32(0);
+      // Offset is poison for ByteAddressBuffer
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spall wrote:

Can you explain to me what this means? 

https://github.com/llvm/llvm-project/pull/176058