[llvm] [SandboxIR] sandboxir::Use operands (part 1) and uses (part 2) (PR #98251)

[via llvm-commits]

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@@ -71,6 +71,98 @@ namespace sandboxir {
 class Function;
 class Context;
 class Instruction;
+class User;
+class Value;
+
+/// Represents a Def-use/Use-def edge in SandboxIR.
+/// NOTE: Unlike llvm::Use, this is not an integral part of the use-def chains.
+/// It is also not uniqued and is currently passed by value, so you can have
+/// more than one sandboxir::Use objects for the same use-def edge.
+class Use {
+  llvm::Use *LLVMUse;
+  User *User;
+  Context *Ctx;
+
+  /// Don't allow the user to create a sandboxir::Use directly.
+  Use(llvm::Use *LLVMUse, class User *User, Context &Ctx)
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vporpo wrote:

It's because of `User *User;` member variable, triggering this error:
```
error: must use 'class' tag to refer to type 'User' in this scope
note: class 'User' is hidden by a non-type declaration of 'User' here
```
So I either have to rename the `User` member variable or use `class User *User` or `sandboxir::User *User` in the arguments.



https://github.com/llvm/llvm-project/pull/98251