[DAG] Change isGCValue detection for statepoint lowering

isGCValue should detect whether the deopt value is a GC pointer.
Currently it checks by finding the value in SI.Bases and SI.Ptrs.
However these data structures contain only those values which
have corresponding gc.relocate call. So we can miss GC value if it
does not have gc.relocate call (dead after the call).

Check GC strategy whether pointer is GC one or consider any pointer
to be GC one conservatively.

Reviewers: reames, dantrushin
Reviewed By: reames
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D77130

Author: Serguei Katkov

llvm/lib/CodeGen/SelectionDAG/StatepointLowering.cpp

@@ -482,8 +482,14 @@ lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
   const bool LiveInDeopt =
     SI.StatepointFlags & (uint64_t)StatepointFlags::DeoptLiveIn;
 
-  auto isGCValue =[&](const Value *V) {
-    return is_contained(SI.Ptrs, V) || is_contained(SI.Bases, V);
+  auto isGCValue = [&](const Value *V) {
+    auto *Ty = V->getType();
+    if (!Ty->isPtrOrPtrVectorTy())
+      return false;
+    if (auto *GFI = Builder.GFI)
+      if (auto IsManaged = GFI->getStrategy().isGCManagedPointer(Ty))
+        return *IsManaged;
+    return true; // conservative
   };
 
   // Before we actually start lowering (and allocating spill slots for values),