[llvm] MCExpr-ify SIProgramInfo (PR #88257)

[Matt Arsenault via llvm-commits]

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@@ -90,6 +90,7 @@ struct SIProgramInfo {
 
     SIProgramInfo() = default;
 
+    // The constructor sets the values for each member as shown in the struct. However, setting the MCExpr members to their zero value equivalent happens in reset together with (duplicated) value re-set for the non-MCExpr members.
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arsenm wrote:

This needs to line wrap 

https://github.com/llvm/llvm-project/pull/88257