[clang] [CIR] Upstream binary assignments and comma (PR #135115)

[Morris Hafner via cfe-commits]

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@@ -807,6 +808,65 @@ class ScalarExprEmitter : public StmtVisitor<ScalarExprEmitter, mlir::Value> {
   VISITCOMP(EQ)
   VISITCOMP(NE)
 #undef VISITCOMP
+
+  mlir::Value VisitBinAssign(const BinaryOperator *e) {
+    const bool ignore = std::exchange(ignoreResultAssign, false);
+
+    mlir::Value rhs;
+    LValue lhs;
+
+    switch (e->getLHS()->getType().getObjCLifetime()) {
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mmha wrote:

Hmm, I don't know about the performance implications (I'd expect them to be insignificant) but I find your suggestion to be less readable. I still need a `case Qualifiers::OCL_None:` with an `llvm_unreachable()` to satisfy clang-tidy and it just adds more branches to the function to follow

https://github.com/llvm/llvm-project/pull/135115