[clang] [CIR] Upstream lowering of conditional operators to TernaryOp (PR #138156)

[Andy Kaylor via cfe-commits]

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@@ -948,6 +950,165 @@ void CIRGenFunction::emitIgnoredExpr(const Expr *e) {
   emitLValue(e);
 }
 
+// Handle the case where the condition is a constant evaluatable simple integer,
+// which means we don't have to separately handle the true/false blocks.
+static std::optional<LValue> handleConditionalOperatorLValueSimpleCase(
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andykaylor wrote:

This is another of those cases where we're doing optimization in the front end. This has come up several times. I personally don't like the idea, but I guess the classic codegen does things like this.

https://github.com/llvm/llvm-project/pull/138156