[llvm] [Coroutines] Refactor CoroShape::buildFrom for future use by ABI objects (PR #108623)

[Chuanqi Xu via llvm-commits]

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@@ -50,15 +50,49 @@ enum class ABI {
 // Holds structural Coroutine Intrinsics for a particular function and other
 // values used during CoroSplit pass.
 struct LLVM_LIBRARY_VISIBILITY Shape {
-  CoroBeginInst *CoroBegin;
+  CoroBeginInst *CoroBegin = nullptr;
   SmallVector<AnyCoroEndInst *, 4> CoroEnds;
   SmallVector<CoroSizeInst *, 2> CoroSizes;
   SmallVector<CoroAlignInst *, 2> CoroAligns;
   SmallVector<AnyCoroSuspendInst *, 4> CoroSuspends;
-  SmallVector<CallInst *, 2> SwiftErrorOps;
   SmallVector<CoroAwaitSuspendInst *, 4> CoroAwaitSuspends;
   SmallVector<CallInst *, 2> SymmetricTransfers;
 
+  // Values invalidated by invalidateCoroutine() and cleanCoroutine()
+  SmallVector<CoroFrameInst *, 8> CoroFrames;
+  SmallVector<CoroSaveInst *, 2> UnusedCoroSaves;
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ChuanqiXu9 wrote:

nit: The name looks slightly odd to me. It looks like they will be cleared in invalidateCoroutine(). This is conflicting with the comment.

And also I like to rename them to `ToBeInvalidatedCoroFrames` and so on. Then in `analyze`, remain the original `CoroFrames` and `UnusedCoroSaves`, let's only assign values to `ToBeInvalidatedCoroFrames` (and so on) when it is invalid actually.

https://github.com/llvm/llvm-project/pull/108623