Minify wasi imports and exports, and not just "env" (#2323)

This makes the minification pass aware of "wasi_unstable" and "wasi" as well.

3 files changed, 17 insertions, 5 deletions

diff --git a/src/passes/MinifyImportsAndExports.cpp b/src/passes/MinifyImportsAndExports.cpp
index d625f7543..0edc85dc7 100644
--- a/src/passes/MinifyImportsAndExports.cpp
+++ b/src/passes/MinifyImportsAndExports.cpp
@@ -143,17 +143,25 @@ private:
     MinifiedNames names;
     size_t soFar = 0;
     std::map<Name, Name> oldToNew;
+    std::map<Name, Name> newToOld;
     auto process = [&](Name& name) {
       // do not minifiy special imports, they must always exist
       if (name == MEMORY_BASE || name == TABLE_BASE || name == STACK_POINTER) {
         return;
       }
-      auto newName = names.getName(soFar++);
-      oldToNew[newName] = name;
-      name = newName;
+      auto iter = oldToNew.find(name);
+      if (iter == oldToNew.end()) {
+        auto newName = names.getName(soFar++);
+        oldToNew[name] = newName;
+        newToOld[newName] = name;
+        name = newName;
+      } else {
+        name = iter->second;
+      }
     };
     auto processImport = [&](Importable* curr) {
-      if (curr->module == ENV) {
+      if (curr->module == ENV || curr->module == WASI ||
+          curr->module == WASI_UNSTABLE) {
         process(curr->base);
       }
     };
@@ -169,7 +177,7 @@ private:
     }
     module->updateMaps();
     // Emit the mapping.
-    for (auto& pair : oldToNew) {
+    for (auto& pair : newToOld) {
       std::cout << pair.second.str << " => " << pair.first.str << '\n';
     }
   }
diff --git a/src/shared-constants.h b/src/shared-constants.h
index 4f64f1cf6..929b173cb 100644
--- a/src/shared-constants.h
+++ b/src/shared-constants.h
@@ -65,6 +65,8 @@ extern Name EXIT;
 extern Name SHARED;
 extern Name EVENT;
 extern Name ATTR;
+extern Name WASI;
+extern Name WASI_UNSTABLE;
 
 } // namespace wasm
 
diff --git a/src/wasm/wasm.cpp b/src/wasm/wasm.cpp
index b13797c89..1a47327c1 100644
--- a/src/wasm/wasm.cpp
+++ b/src/wasm/wasm.cpp
@@ -88,6 +88,8 @@ Name EXIT("exit");
 Name SHARED("shared");
 Name EVENT("event");
 Name ATTR("attr");
+Name WASI("wasi");
+Name WASI_UNSTABLE("wasi_unstable");
 
 // Expressions