[llvm] Reapply [AMDGPU] Avoid resource propagation for recursion through multiple functions (PR #112251)

[Fangrui Song via llvm-commits]

MaskRay wrote:

The `isSymbolUsedInExpression` use within `parseAssignmentExpression` is a hack and should not be used externally. 
```
  if (Sym) {
    // Diagnose assignment to a label.
    //
    // FIXME: Diagnostics. Note the location of the definition as a label.
    // FIXME: Diagnose assignment to protected identifier (e.g., register name).
    if (Value->isSymbolUsedInExpression(Sym))
      return Parser.Error(EqualLoc, "Recursive use of '" + Name + "'");
    else if (Sym->isUndefined(/*SetUsed*/ false) && !Sym->isUsed() &&
             !Sym->isVariable())
      ; // Allow redefinitions of undefined symbols only used in directives.
    else if (Sym->isVariable() && !Sym->isUsed() && allow_redef)
      ; // Allow redefinitions of variables that haven't yet been used.
    else if (!Sym->isUndefined() && (!Sym->isVariable() || !allow_redef))
      return Parser.Error(EqualLoc, "redefinition of '" + Name + "'");
    else if (!Sym->isVariable())
      return Parser.Error(EqualLoc, "invalid assignment to '" + Name + "'");
    else if (!isa<MCConstantExpr>(Sym->getVariableValue()))
      return Parser.Error(EqualLoc,
                          "invalid reassignment of non-absolute variable '" +
                              Name + "'");
  } else if (Name == ".") {
```

If I ever have time to clean it, I think the traversal should be moved to AMDGPU.

https://github.com/llvm/llvm-project/pull/112251