jeremy-code · Nov 14, 2026 · jeremy-code · Nov 14, 2026
diff --git a/src/passes/RemoveImports.cpp b/src/passes/RemoveImports.cpp
@@ -21,20 +21,54 @@
 // imports, we can at least get the reference interpreter to
 // look at all the rest of the code).
 //
+// By default, all imports are removed. Imports can be specified as a
+// comma-separated list with format module.base (with or without wildcards) or
+// as a response file.
 
 #include "ir/element-utils.h"
 #include "ir/module-utils.h"
 #include "pass.h"
+#include "support/file.h"
+#include "support/string.h"
 #include "wasm.h"
 
 namespace wasm {
 
 struct RemoveImports : public WalkerPass<PostWalker<RemoveImports>> {
+  std::set<Name> toRemove;
+
+  void run(Module* module) override {
+    toRemove.clear();
+
+    // If no arguments are provided, all function imports are removed.
+    std::string param = getArgumentOrDefault(name, "");
+    param = String::trim(read_possible_response_file(param));
+    bool removeAllImports = param.empty();
+
+    String::Split patterns(param, String::Split::NewLineOr(","));
+    patterns = handleBracketingOperators(patterns);
+
+    ModuleUtils::iterImportedFunctions(*module, [&](Function* func) {
+      if (removeAllImports) {
+        toRemove.insert(func->name);
+        return;
+      }
+      auto full = func->module.toString() + '.' + func->base.toString();
 static std::string getFullImportName(Name module, Name base) { 
   return module.toString() + '.' + base.toString(); 
 } 
 static std::string getFullImportName(Name module, Name base) { 
   return module.toString() + '.' + base.toString(); 
 } 
+      for (auto& pattern : patterns) {
+        if (String::wildcardMatch(pattern, full)) {
+          toRemove.insert(func->name);
+          break;
+        }
+      }
+    });
+    WalkerPass<PostWalker<RemoveImports>>::run(module);
+  }
+
   void visitCall(Call* curr) {
-    auto* func = getModule()->getFunction(curr->target);
-    if (!func->imported()) {
+    if (!toRemove.count(curr->target)) {
       return;
     }
+    auto* func = getModule()->getFunction(curr->target);
     Type type = func->getResults();
     if (type == Type::none) {
       replaceCurrent(getModule()->allocator.alloc<Nop>());
@@ -45,14 +79,11 @@ struct RemoveImports : public WalkerPass<PostWalker<RemoveImports>> {
   }
 
   void visitModule(Module* curr) {
-    std::vector<Name> names;
-    ModuleUtils::iterImportedFunctions(
-      *curr, [&](Function* func) { names.push_back(func->name); });
     // Do not remove names referenced in a table
     std::set<Name> indirectNames;
     ElementUtils::iterAllElementFunctionNames(
       curr, [&](Name name) { indirectNames.insert(name); });
-    for (auto& name : names) {
+    for (auto& name : toRemove) {
       if (indirectNames.find(name) == indirectNames.end()) {
         curr->removeFunction(name);
       }

diff --git a/src/passes/pass.cpp b/src/passes/pass.cpp
@@ -445,7 +445,7 @@ void PassRegistry::registerPasses() {
                "removes exports using a wildcard",
                createRemoveExportsPass);
   registerPass("remove-imports",
-               "removes imports and replaces them with nops",
+               "removes imports using a wildcard and replaces them with nops",
                createRemoveImportsPass);
   registerPass("remove-memory-init",
                "removes memory initialization",

diff --git a/test/lit/help/wasm-metadce.test b/test/lit/help/wasm-metadce.test
@@ -414,8 +414,8 @@
 ;; CHECK-EMPTY:
 ;; CHECK-NEXT:   --remove-exports                              removes exports using a wildcard
 ;; CHECK-EMPTY:
-;; CHECK-NEXT:   --remove-imports                              removes imports and replaces 
-;; CHECK-NEXT:                                                 them with nops
+;; CHECK-NEXT:   --remove-imports                              removes imports using a wildcard
+;; CHECK-NEXT:                                                 and replaces them with nops
 ;; CHECK-EMPTY:
 ;; CHECK-NEXT:   --remove-memory                               removes memory init (legacy 
 ;; CHECK-NEXT:                                                 name)

diff --git a/test/lit/help/wasm-opt.test b/test/lit/help/wasm-opt.test
@@ -459,8 +459,8 @@
 ;; CHECK-EMPTY:
 ;; CHECK-NEXT:   --remove-exports                              removes exports using a wildcard
 ;; CHECK-EMPTY:
-;; CHECK-NEXT:   --remove-imports                              removes imports and replaces 
-;; CHECK-NEXT:                                                 them with nops
+;; CHECK-NEXT:   --remove-imports                              removes imports using a wildcard
+;; CHECK-NEXT:                                                 and replaces them with nops
 ;; CHECK-EMPTY:
 ;; CHECK-NEXT:   --remove-memory                               removes memory init (legacy 
 ;; CHECK-NEXT:                                                 name)

diff --git a/test/lit/help/wasm2js.test b/test/lit/help/wasm2js.test
@@ -378,8 +378,8 @@
 ;; CHECK-EMPTY:
 ;; CHECK-NEXT:   --remove-exports                              removes exports using a wildcard
 ;; CHECK-EMPTY:
-;; CHECK-NEXT:   --remove-imports                              removes imports and replaces 
-;; CHECK-NEXT:                                                 them with nops
+;; CHECK-NEXT:   --remove-imports                              removes imports using a wildcard 
+;; CHECK-NEXT:                                                 and replaces them with nops
 ;; CHECK-EMPTY:
 ;; CHECK-NEXT:   --remove-memory                               removes memory init (legacy 
 ;; CHECK-NEXT:                                                 name)

diff --git a/test/lit/passes/remove-imports-file.txt b/test/lit/passes/remove-imports-file.txt
@@ -0,0 +1,3 @@
+env.foo
+other.*
+*.log.*
diff --git a/test/lit/passes/remove-imports-file.wast b/test/lit/passes/remove-imports-file.wast
@@ -0,0 +1,32 @@
+;; NOTE: Assertions have been generated by update_lit_checks.py --all-items and should not be edited.
+
+;; RUN: foreach %s %t wasm-opt --remove-imports=@%S/remove-imports-file.txt -all -S -o - | filecheck %s
+
+;; Test a response file as the input to this pass. env.foo, other.baz,
+;; env.log.warn will be removed.
+(module
+  (import "env" "foo" (func $foo))
+  ;; CHECK:      (type $0 (func))
+
+  ;; CHECK:      (import "env" "keep" (func $keep (type $0)))
+  (import "env" "keep" (func $keep))
+  (import "other" "baz" (func $baz (result i32)))
+  (import "env" "log.warn" (func $log.warn))
+
+  ;; CHECK:      (func $test (type $0)
+  ;; CHECK-NEXT:  (nop)
+  ;; CHECK-NEXT:  (call $keep)
+  ;; CHECK-NEXT:  (drop
+  ;; CHECK-NEXT:   (i32.const 0)
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT:  (nop)
+  ;; CHECK-NEXT: )
+  (func $test
+    (call $foo)
+    (call $keep)
+    (drop
+      (call $baz)
+    )
+    (call $log.warn)
+  )
+)
diff --git a/test/lit/passes/remove-imports-list.wast b/test/lit/passes/remove-imports-list.wast
@@ -0,0 +1,31 @@
+;; NOTE: Assertions have been generated by update_lit_checks.py --all-items and should not be edited.
+
+;; RUN: foreach %s %t wasm-opt "--remove-imports=env.foo,other.*,*.log.*" -all -S -o - | filecheck %s
+
+;; The imports will be removed except env.keep.
+(module
+  (import "env" "foo" (func $foo))
+  ;; CHECK:      (type $0 (func))
+
+  ;; CHECK:      (import "env" "keep" (func $keep (type $0)))
+  (import "env" "keep" (func $keep))
+  (import "other" "baz" (func $baz (result i32)))
+  (import "env" "log.warn" (func $log.warn))
+
+  ;; CHECK:      (func $test (type $0)
+  ;; CHECK-NEXT:  (nop)
+  ;; CHECK-NEXT:  (call $keep)
+  ;; CHECK-NEXT:  (drop
+  ;; CHECK-NEXT:   (i32.const 0)
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT:  (nop)
+  ;; CHECK-NEXT: )
+  (func $test
+    (call $foo)
+    (call $keep)
+    (drop
+      (call $baz)
+    )
+    (call $log.warn)
+  )
+)
-Original file line number
+Diff line change
@@ -0,0 +1,3 @@
+    env.foo
+    other.*
+    *.log.*