[clang] [Clang][CodeGen] Do not emit lifetime intrinsics for coro promise alloca (PR #140548)

[Chuanqi Xu via cfe-commits]

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@@ -1599,9 +1599,14 @@ CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
       bool IsMSCatchParam =
           D.isExceptionVariable() && getTarget().getCXXABI().isMicrosoft();
 
+      // No lifetime intrinsics on coroutine promise alloca, or middle end
+      // passes will assume promise dead after lifetime.end, leading to
+      // mis-optimization
+      bool IsCoroPromise = D.getName() == "__promise";
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ChuanqiXu9 wrote:

We should avoid comparing string as much as possible. And also it is not good to insert coroutines logic to `CGDecl.cpp`. We'd either doing this in CGCoroutine or CoroEarly.

https://github.com/llvm/llvm-project/pull/140548