llvm/llvm/test/Transforms/Coroutines/coro-split-01.ll

; Tests that a coroutine is split, inlined into the caller and devirtualized.
; RUN: opt < %s -S -passes='default<O2>' | FileCheck %s

define ptr @f() presplitcoroutine {
entry:
  %id = call token @llvm.coro.id(i32 0, ptr null, ptr null, ptr null)
  %need.dyn.alloc = call i1 @llvm.coro.alloc(token %id)
  br i1 %need.dyn.alloc, label %dyn.alloc, label %coro.begin
dyn.alloc:
  %size = call i32 @llvm.coro.size.i32()
  %alloc = call ptr @malloc(i32 %size)
  br label %coro.begin
coro.begin:
  %phi = phi ptr [ null, %entry ], [ %alloc, %dyn.alloc ]
  %hdl = call ptr @llvm.coro.begin(token %id, ptr %phi)
  call void @print(i32 0)
  %0 = call i8 @llvm.coro.suspend(token none, i1 false)
  switch i8 %0, label %suspend [i8 0, label %resume 
                                i8 1, label %cleanup]
resume:
  call void @print(i32 1)
  br label %cleanup

cleanup:
  %mem = call ptr @llvm.coro.free(token %id, ptr %hdl)
  call void @free(ptr %mem)
  br label %suspend
suspend:
  call i1 @llvm.coro.end(ptr %hdl, i1 0, token none)  
  ret ptr %hdl
}
define i32 @main() {
entry:
  %hdl = call ptr @f()
  call void @llvm.coro.resume(ptr %hdl)
  ret i32 0
; CHECK-LABEL: @main(
; CHECK: call void @print(i32 0)
; CHECK: call void @print(i32 1)
; CHECK:      ret i32 0
}

declare ptr @llvm.coro.free(token, ptr)
declare i32 @llvm.coro.size.i32()
declare i8  @llvm.coro.suspend(token, i1)
declare void @llvm.coro.resume(ptr)
declare void @llvm.coro.destroy(ptr)
  
declare token @llvm.coro.id(i32, ptr, ptr, ptr)
declare i1 @llvm.coro.alloc(token)
declare ptr @llvm.coro.begin(token, ptr)
declare i1 @llvm.coro.end(ptr, i1, token) 

declare noalias ptr @malloc(i32)
declare void @print(i32)
declare void @free(ptr)