[coroutines] CoroBegin from inner coroutines should be considered for spills

Summary:
If a coroutine outer calls another coroutine inner and the inner coroutine body is inlined into the outer, coro.begin from the inner coroutine should be considered for spilling if accessed across suspends.

Prior to this change, coroutine frame building code was not considering any coro.begins for spilling.
With this change, we only ignore coro.begin for the current coroutine, but, any coro.begins that were inlined into the current coroutine are eligible for spills.

Fixes PR34267

Reviewers: GorNishanov

Subscribers: qcolombet, llvm-commits, EricWF

Differential Revision: https://reviews.llvm.org/D37062

llvm-svn: 311556

1 files changed, 3 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.