2 files changed, 72 insertions, 3 deletions
diff --git a/llvm/lib/Transforms/Coroutines/CoroFrame.cpp b/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
index 85e9003ec3c..d192fa699f3 100644
--- a/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
+++ b/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
@@ -673,8 +673,8 @@ static bool materializable(Instruction &V) {
 // Check for structural coroutine intrinsics that should not be spilled into
 // the coroutine frame.
 static bool isCoroutineStructureIntrinsic(Instruction &I) {
-  return isa<CoroIdInst>(&I) || isa<CoroBeginInst>(&I) ||
-         isa<CoroSaveInst>(&I) || isa<CoroSuspendInst>(&I);
+  return isa<CoroIdInst>(&I) || isa<CoroSaveInst>(&I) ||
+         isa<CoroSuspendInst>(&I);
 }
 
 // For every use of the value that is across suspend point, recreate that value
@@ -839,7 +839,7 @@ void coro::buildCoroutineFrame(Function &F, Shape &Shape) {
   for (Instruction &I : instructions(F)) {
     // Values returned from coroutine structure intrinsics should not be part
     // of the Coroutine Frame.
-    if (isCoroutineStructureIntrinsic(I))
+    if (isCoroutineStructureIntrinsic(I) || &I == Shape.CoroBegin)
       continue;
     // The Coroutine Promise always included into coroutine frame, no need to
     // check for suspend crossing.
diff --git a/llvm/test/Transforms/Coroutines/coro-spill-corobegin.ll b/llvm/test/Transforms/Coroutines/coro-spill-corobegin.ll
new file mode 100644
index 00000000000..e57e2f28ed3
--- /dev/null
+++ b/llvm/test/Transforms/Coroutines/coro-spill-corobegin.ll
@@ -0,0 +1,69 @@
+; Check that we can spills coro.begin from an inlined inner coroutine.
+; RUN: opt < %s -coro-split -S | FileCheck %s
+
+%g.Frame = type { void (%g.Frame*)*, void (%g.Frame*)*, i32, i1, i32 }
+
+@g.resumers = private constant [3 x void (%g.Frame*)*] [void (%g.Frame*)* @g.dummy, void (%g.Frame*)* @g.dummy, void (%g.Frame*)* @g.dummy]
+
+declare void @g.dummy(%g.Frame*)
+
+define i8* @f() "coroutine.presplit"="1" {
+entry:
+  %id = call token @llvm.coro.id(i32 0, i8* null, i8* null, i8* null)
+  %size = call i32 @llvm.coro.size.i32()
+  %alloc = call i8* @malloc(i32 %size)
+  %hdl = call i8* @llvm.coro.begin(token %id, i8* %alloc)
+
+  %innerid = call token @llvm.coro.id(i32 0, i8* null, i8* null, i8* bitcast ([3 x void (%g.Frame*)*]* @g.resumers to i8*))
+  %innerhdl = call noalias nonnull i8* @llvm.coro.begin(token %innerid, i8* null)
+  %gframe = bitcast i8* %innerhdl to %g.Frame*
+
+  %tok = call i8 @llvm.coro.suspend(token none, i1 false)
+  switch i8 %tok, label %suspend [i8 0, label %resume
+                                i8 1, label %cleanup]
+resume:
+  %gvar.addr = getelementptr inbounds %g.Frame, %g.Frame* %gframe, i32 0, i32 4
+  %gvar = load i32, i32* %gvar.addr
+  call void @print.i32(i32 %gvar)
+  br label %cleanup
+
+cleanup:
+  %mem = call i8* @llvm.coro.free(token %id, i8* %hdl)
+  call void @free(i8* %mem)
+  br label %suspend
+suspend:
+  call i1 @llvm.coro.end(i8* %hdl, i1 0)
+  ret i8* %hdl
+}
+
+; See if the i8* for coro.begin was added to f.Frame
+; CHECK-LABEL: %f.Frame = type { void (%f.Frame*)*, void (%f.Frame*)*, i1, i1, i8* }
+
+; See if the g's coro.begin was spilled into the frame
+; CHECK-LABEL: @f(
+; CHECK: %innerid = call token @llvm.coro.id(i32 0, i8* null, i8* null, i8* bitcast ([3 x void (%g.Frame*)*]* @g.resumers to i8*))
+; CHECK: %innerhdl = call noalias nonnull i8* @llvm.coro.begin(token %innerid, i8* null)
+; CHECK: %[[spilladdr:.+]] = getelementptr inbounds %f.Frame, %f.Frame* %FramePtr, i32 0, i32 4
+; CHECK: store i8* %innerhdl, i8** %[[spilladdr]]
+
+; See if the coro.begin was loaded from the frame
+; CHECK-LABEL: @f.resume(
+; CHECK: %[[innerhdlAddr:.+]] = getelementptr inbounds %f.Frame, %f.Frame* %{{.+}}, i32 0, i32 4
+; CHECK: %[[innerhdl:.+]] = load i8*, i8** %[[innerhdlAddr]]
+; CHECK: %[[gframe:.+]] = bitcast i8* %[[innerhdl]] to %g.Frame*
+; CHECK: %[[gvarAddr:.+]] = getelementptr inbounds %g.Frame, %g.Frame* %[[gframe]], i32 0, i32 4
+; CHECK: %[[gvar:.+]] = load i32, i32* %[[gvarAddr]]
+; CHECK: call void @print.i32(i32 %[[gvar]])
+
+declare i8* @llvm.coro.free(token, i8*)
+declare i32 @llvm.coro.size.i32()
+declare i8  @llvm.coro.suspend(token, i1)
+
+declare token @llvm.coro.id(i32, i8*, i8*, i8*)
+declare i1 @llvm.coro.alloc(token)
+declare i8* @llvm.coro.begin(token, i8*)
+declare i1 @llvm.coro.end(i8*, i1)
+
+declare noalias i8* @malloc(i32)
+declare void @print.i32(i32)
+declare void @free(i8*)