[Legacy Driver][wasm] Pass --table-base to reserve low function addresses

lib/Driver/WebAssemblyToolChains.cpp

@@ -188,12 +188,16 @@ toolchains::WebAssembly::constructInvocation(const DynamicLinkJobAction &job,
 
   // WebAssembly doesn't reserve low addresses But without "extra inhabitants"
   // of the pointer representation, runtime performance and memory footprint are
-  // worse. So assume that compiler driver uses wasm-ld and --global-base=1024
-  // to reserve low 1KB.
+  // worse. So assume that compiler driver uses wasm-ld and --global-base=4096
+  // to reserve low 4KB.
   Arguments.push_back("-Xlinker");
   Arguments.push_back(context.Args.MakeArgString(
       Twine("--global-base=") +
       std::to_string(SWIFT_ABI_WASM32_LEAST_VALID_POINTER)));
+  Arguments.push_back("-Xlinker");
+  Arguments.push_back(context.Args.MakeArgString(
+      Twine("--table-base=") +
+      std::to_string(SWIFT_ABI_WASM32_LEAST_VALID_POINTER)));
 
   // These custom arguments should be right before the object file at the end.
   context.Args.AddAllArgs(Arguments, options::OPT_linker_option_Group);

stdlib/public/SwiftShims/swift/shims/System.h

@@ -220,8 +220,8 @@
 
 // WebAssembly doesn't reserve low addresses. But without "extra inhabitants" of
 // the pointer representation, runtime performance and memory footprint are
-// worse. So assume that compiler driver uses wasm-ld and --global-base=1024 to
-// reserve low 1KB.
+// worse. So assume that compiler driver uses wasm-ld and --global-base=4096 to
+// reserve low 4KB.
 #define SWIFT_ABI_WASM32_LEAST_VALID_POINTER 4096
 
 #endif // SWIFT_STDLIB_SHIMS_ABI_SYSTEM_H

test/Interpreter/enum.swift

@@ -745,3 +745,45 @@ func reproduction<T: Init>(_ x: Int, _ y: Int, _ t: T) {
 
 // CHECK: there is no byte
 reproduction(2, 3, TrailingByte())
+
+do {
+  // regression test for https://github.com/swiftlang/swift-driver/pull/1987
+  @inline(never) func blackhole<T>(_ t: T) { }
+
+  final class Context {
+    func doSomething() {}
+    deinit {
+      print("Context deinit")
+    }
+  }
+
+  enum MyOptional<Value> {
+    case some(Value)
+    case none
+  }
+
+  final class _GenericStorage<Value> {
+    let value: MyOptional<Value>
+
+    init(value: Value) {
+      self.value = .some(value)
+    }
+
+    func unwrapAndCopy() {
+      if case .some(let value) = value {
+        blackhole(value)
+      }
+    }
+  }
+
+  let test = _GenericStorage(
+    value: Context().doSomething,
+  )
+  // CHECK: test.unwrapAndCopy
+  print("test.unwrapAndCopy")
+  test.unwrapAndCopy()
+  // CHECK: test.unwrapAndCopy
+  print("test.unwrapAndCopy")
+  test.unwrapAndCopy()
+  // CHECK: Context deinit
+}

utils/swift_build_support/swift_build_support/products/wasmstdlib.py

@@ -191,7 +191,11 @@ def _build_stdlib(self, host_target, target_triple, llvm_cmake_dir):
         # Test configuration
         self.cmake_options.define('SWIFT_INCLUDE_TESTS:BOOL', 'TRUE')
         self.cmake_options.define('SWIFT_ENABLE_SOURCEKIT_TESTS:BOOL', 'FALSE')
-        lit_test_paths = ['IRGen', 'stdlib', 'Concurrency/Runtime', 'embedded']
+        lit_test_paths = [
+            'IRGen', 'stdlib', 'Concurrency/Runtime', 'embedded',
+            # TODO(katei): Enable all interpreter tests
+            'Interpreter/enum.swift',
+        ]
         lit_test_paths = [os.path.join(
             self.build_dir, 'test-wasi-wasm32', path) for path in lit_test_paths]
         self.cmake_options.define('SWIFT_LIT_TEST_PATHS:STRING',