add remove-imports pass

1 files changed, 36 insertions, 0 deletions

diff --git a/src/passes/RemoveImports.cpp b/src/passes/RemoveImports.cpp
new file mode 100644
index 000000000..07465f9d6
--- /dev/null
+++ b/src/passes/RemoveImports.cpp
@@ -0,0 +1,36 @@
+//
+// Removeds imports, and replaces them with nops. This is useful
+// for running a module through the reference interpreter, which
+// does not validate imports for a JS environment (by removing
+// imports, we can at least get the reference interpreter to
+// look at all the rest of the code).
+//
+
+#include <wasm.h>
+#include <pass.h>
+
+namespace wasm {
+
+struct RemoveImports : public Pass {
+  MixedArena* allocator;
+
+  void prepare(PassRunner* runner, Module *module) override {
+    allocator = runner->allocator;
+  }
+
+  void visitCallImport(CallImport *curr) override {
+    replaceCurrent(allocator->alloc<Nop>());
+  }
+
+  void visitModule(Module *curr) {
+    auto imports = curr->imports;
+    for (auto import : imports) {
+      curr->removeImport(import->name);
+    }
+  }
+};
+
+static RegisterPass<RemoveImports> registerPass("remove-imports", "removes imports and replaces them with nops");
+
+} // namespace wasm
+