1 files changed, 34 insertions, 0 deletions
diff --git a/llvm/test/Transforms/RewriteStatepointsForGC/unreachable-regression.ll b/llvm/test/Transforms/RewriteStatepointsForGC/unreachable-regression.ll
new file mode 100644
index 00000000000..1f781a4ce19
--- /dev/null
+++ b/llvm/test/Transforms/RewriteStatepointsForGC/unreachable-regression.ll
@@ -0,0 +1,34 @@
+; RUN: opt -S -rewrite-statepoints-for-gc < %s | FileCheck %s
+; RUN: opt -S -passes=rewrite-statepoints-for-gc < %s | FileCheck %s
+;
+; Regression test:
+;   After the rewritable callsite collection if any callsite was found
+;   in a block that was reported unreachable by DominanceTree then
+;   removeUnreachableBlocks() was called. But it is stronger than
+;   DominatorTree::isReachableFromEntry(), i.e. removeUnreachableBlocks
+;   can remove some blocks for which isReachableFromEntry() returns true.
+;   This resulted in stale pointers to the collected but removed
+;   callsites. Such stale pointers caused crash when accessed.
+declare void @f(i8 addrspace(1)* %obj)
+
+define void @test(i8 addrspace(1)* %arg) gc "statepoint-example" {
+; CHECK-LABEL: test(
+; CHECK-NEXT: @f
+ call void @f(i8 addrspace(1)* %arg) #1
+ br i1 true, label %not_zero, label %zero
+
+not_zero:
+ ret void
+
+; This block is reachable but removed by removeUnreachableBlocks()
+zero:
+; CHECK-NOT: @f
+ call void @f(i8 addrspace(1)* %arg) #1
+ ret void
+
+unreach:
+ call void @f(i8 addrspace(1)* %arg) #1
+ ret void
+}
+
+attributes #1 = { norecurse noimplicitfloat }