Add WasmPointersSpill pass to force potential pointers onto stack

gen/optimizer.cpp

@@ -26,6 +26,7 @@
 #include "gen/passes/GarbageCollect2Stack.h"
 #include "gen/passes/StripExternals.h"
 #include "gen/passes/SimplifyDRuntimeCalls.h"
+#include "gen/passes/WasmPointersSpill.h"
 #include "gen/passes/Passes.h"
 
 #ifndef IN_JITRT
@@ -333,6 +334,19 @@ static void addGarbageCollect2StackPass(ModulePassManager &mpm,
   }
 }
 
+static void addWasmPointersSpillPass(ModulePassManager &mpm,
+                                         OptimizationLevel level
+#if LLVM_VERSION_MAJOR >= 20
+                                         ,
+                                         ThinOrFullLTOPhase
+#endif
+) {
+  mpm.addPass(createModuleToFunctionPassAdaptor(WasmPointersSpillPass()));
+  if (verifyEach) {
+    mpm.addPass(VerifierPass());
+  }
+}
+
 #ifndef IN_JITRT
 static std::optional<PGOOptions> getPGOOptions() {
   // FIXME: Do we have these anywhere?
@@ -511,6 +525,10 @@ void runOptimizationPasses(llvm::Module *M, llvm::TargetMachine *TM) {
 
   pb.registerOptimizerLastEPCallback(addStripExternalsPass);
 
+  if (TM->getTargetTriple().isWasm()) {
+    pb.registerOptimizerLastEPCallback(addWasmPointersSpillPass);
+  }
+
 #ifndef IN_JITRT
   registerAllPluginsWithPassBuilder(pb);
 #endif

gen/passes/Passes.h

@@ -23,6 +23,8 @@ llvm::FunctionPass *createSimplifyDRuntimeCalls();
 
 llvm::FunctionPass *createGarbageCollect2Stack();
 
+llvm::FunctionPass *createWasmPointersSpillPass();
+
 llvm::ModulePass *createStripExternalsPass();
 
 llvm::ModulePass *createDLLImportRelocationPass();