[RS4GC] Add a comment
llvm-svn: 265503
diff --git a/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp b/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp
index db1af57..6e6a776 100644
--- a/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp
+++ b/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp
@@ -1366,6 +1366,10 @@
Flags |= uint32_t(StatepointFlags::GCTransition);
TransitionArgs = TransitionBundle->Inputs;
}
+
+ // Instead of lowering calls to @llvm.experimental.deoptimize as normal calls
+ // with a return value, we lower then as never returning calls to
+ // __llvm_deoptimize that are followed by unreachable to get better codegen.
bool IsDeoptimize = false;
StatepointDirectives SD =