[WebAssembly] Add TODO comment to revisit red zone size

llvm-svn: 261664

diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.h b/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.h
index cb3b011..0422e1f 100644 (file)
--- a/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.h
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.h
@@ -23,6 +23,9 @@ class MachineFrameInfo;
 
 class WebAssemblyFrameLowering final : public TargetFrameLowering {
  public:
+  /// Size of the red zone for the user stack (leaf functions can use this much
+  /// space below the stack pointer without writing it back to memory).
+  // TODO: (ABI) Revisit and decide how large it should be.
   static const size_t RedZoneSize = 128;
 
   WebAssemblyFrameLowering()