[clang] [llvm] [mlir] [Coroutines] Add llvm.coro.is_in_ramp and drop return value of llvm.coro.end (PR #153404)

[Weibo He via cfe-commits]

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@@ -2117,6 +2118,30 @@ Example:
       %hdl.result = ... ; get address of returned coroutine handle
       ret ptr %hdl.result
 
+'llvm.coro.where' Intrinsic
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+::
+
+  declare i1 @llvm.coro.where()
+
+Overview:
+"""""""""
+
+The '``llvm.coro.where``' intrinsic returns a bool value that marks coroutine resume
+part and start part.
+
+Arguments:
+""""""""""
+
+None
+
+Semantics:
+""""""""""
+
+The `CoroSpit` pass replaces `coro.where` with ``True`` in the resume functions,
+whereas in start function it is replaced with ``False``, thus allowing the frontend
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NewSigma wrote:

Done

https://github.com/llvm/llvm-project/pull/153404