[WebAssembly] Handle EH terminate pads for cleanup

Terminate pads, cleanup pads with `__clang_call_terminate` call, have
`catch` instruction in them because `__clang_call_terminate` takes an
exception pointer. But these terminate pads should be reached also in
case of foreign exception. So this pass attaches an additional
`catch_all` BB after every terminate pad BB, with a call to
`std::terminate`.

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D94050

1 files changed, 5 insertions, 0 deletions

diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
index 135055a..0b07850 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
@@ -82,6 +82,7 @@ extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeWebAssemblyTarget() {
   initializeWebAssemblyExceptionInfoPass(PR);
   initializeWebAssemblyCFGSortPass(PR);
   initializeWebAssemblyCFGStackifyPass(PR);
+  initializeWebAssemblyHandleEHTerminatePadsPass(PR);
   initializeWebAssemblyExplicitLocalsPass(PR);
   initializeWebAssemblyLowerBrUnlessPass(PR);
   initializeWebAssemblyRegNumberingPass(PR);
@@ -485,6 +486,10 @@ void WebAssemblyPassConfig::addPreEmitPass() {
   // Insert BLOCK and LOOP markers.
   addPass(createWebAssemblyCFGStackify());
 
+  // Handle terminate pads for cleanups
+  if (TM->Options.ExceptionModel == ExceptionHandling::Wasm)
+    addPass(createWebAssemblyHandleEHTerminatePads());
+
   // Insert explicit local.get and local.set operators.
   if (!WasmDisableExplicitLocals)
     addPass(createWebAssemblyExplicitLocals());