[clang] [CIR] Upstream CastOp and scalar conversions (PR #130690)

[Erich Keane via cfe-commits]

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@@ -36,6 +36,18 @@ class ScalarExprEmitter : public StmtVisitor<ScalarExprEmitter, mlir::Value> {
                     bool ira = false)
       : cgf(cgf), builder(builder), ignoreResultAssign(ira) {}
 
+  //===--------------------------------------------------------------------===//
+  //                               Utilities
+  //===--------------------------------------------------------------------===//
+
+  bool TestAndClearIgnoreResultAssign() {
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erichkeane wrote:

Oh boy this name is a bit of a word-soup :D  This is actually more of an `exchange` in c++ parlance.

https://github.com/llvm/llvm-project/pull/130690