[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:

I would prefer to see it happen in CIRSimplify. Especially in the case of a ternary operator, I wouldn't expect it to be common for there to be a lot of dead code.

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