[clang] [llvm] [RFC][Coroutines] Implement HALO for coroutines that flow off final suspend (PR #185336)

[Weibo He via cfe-commits]

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@@ -1100,10 +1100,9 @@ void coro::SwitchCloner::create() {
   // Clone the function
   coro::BaseCloner::create();
 
-  // Eliminate coro.free from the clones, replacing it with 'null' in cleanup,
-  // to suppress deallocation code.
-  coro::replaceCoroFree(cast<CoroIdInst>(VMap[Shape.CoroBegin->getId()]),
-                        /*Elide=*/FKind == coro::CloneKind::SwitchCleanup);
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NewSigma wrote:

Here we lower `coro.free` only if `coro.alloc` exists. The rest is deferred to CoroCleanup as well.

https://github.com/llvm/llvm-project/pull/185336