[Macros] Add support for wasm macros

include/swift/Option/Options.td

@@ -173,12 +173,12 @@ def verify_incremental_dependencies :
   Flag<["-"], "verify-incremental-dependencies">,
   Flags<[FrontendOption, HelpHidden]>,
   HelpText<"Enable the dependency verifier for each frontend job">;
-  
+
 def strict_implicit_module_context :
   Flag<["-"], "strict-implicit-module-context">,
   Flags<[FrontendOption, HelpHidden]>,
   HelpText<"Enable the strict forwarding of compilation context to downstream implicit module dependencies">;
-  
+
 def no_strict_implicit_module_context :
   Flag<["-"], "no-strict-implicit-module-context">,
   Flags<[FrontendOption, HelpHidden]>,
@@ -315,7 +315,7 @@ def tools_directory : Separate<["-"], "tools-directory">,
 
 def D : JoinedOrSeparate<["-"], "D">, Flags<[FrontendOption]>,
   HelpText<"Marks a conditional compilation flag as true">;
-  
+
 def e : Separate<["-"], "e">, Flags<[NewDriverOnlyOption]>,
   HelpText<"Executes a line of code provided on the command line">;
 
@@ -2106,7 +2106,7 @@ def external_plugin_path : Separate<["-"], "external-plugin-path">, Group<plugin
   Flags<[FrontendOption, ArgumentIsPath, SwiftSymbolGraphExtractOption, SwiftAPIDigesterOption]>,
   HelpText<"Add directory to the plugin search path with a plugin server executable">,
   MetaVarName<"<path>#<plugin-server-path>">;
-  
+
 def cas_backend: Flag<["-"], "cas-backend">,
   Flags<[FrontendOption, NoDriverOption]>,
   HelpText<"Enable using CASBackend for object file output">;

lib/Basic/Sandbox.cpp

@@ -24,8 +24,8 @@ static StringRef sandboxProfile(llvm::BumpPtrAllocator &Alloc) {
   // Allow reading file metadata of any files.
   contents += "(allow file-read-metadata)\n";
 
-  // Allow reading dylibs.
-  contents += "(allow file-read* (regex #\"\\.dylib$\"))\n";
+  // Allow reading dylibs and WebAssembly macros.
+  contents += "(allow file-read* (regex #\"\\.(dylib|wasm)$\"))\n";
 
   // This is required to launch any processes (execve(2)).
   contents += "(allow process-exec*)\n";

test/Macros/Inputs/wasi_shim.h

@@ -0,0 +1,55 @@
+// definitions from
+// https://github.com/WebAssembly/wasi-libc/blob/320bbbcced68ce8e564b0dc4c8f80a5a5ad21a9c/libc-bottom-half/headers/public/wasi/api.h
+
+typedef unsigned char uint8_t;
+typedef unsigned short uint16_t;
+typedef unsigned int uint32_t;
+typedef unsigned long long uint64_t;
+
+typedef uint8_t wasi_signal_t;
+typedef uint16_t wasi_errno_t;
+typedef uint32_t wasi_exitcode_t;
+typedef int wasi_fd_t;
+typedef __SIZE_TYPE__ wasi_size_t;
+
+typedef struct wasi_ciovec_t {
+  const uint8_t *buf;
+  wasi_size_t buf_len;
+} wasi_ciovec_t;
+
+wasi_errno_t wasi_fd_write(
+  wasi_fd_t fd,
+  const wasi_ciovec_t *iovs,
+  wasi_size_t iovs_len,
+  wasi_size_t *nwritten
+) __attribute__((
+  __import_module__("wasi_snapshot_preview1"),
+  __import_name__("fd_write"),
+  __warn_unused_result__
+));
+
+_Noreturn void wasi_proc_exit(
+  wasi_exitcode_t code
+) __attribute__((
+  __import_module__("wasi_snapshot_preview1"),
+  __import_name__("proc_exit")
+));
+
+// libc shims
+
+static inline wasi_size_t swift_strlen(const char *buf) {
+  wasi_size_t len = 0;
+  while (buf[len]) len++;
+  return len;
+}
+
+static inline wasi_errno_t swift_write(int fd, const void *buf, wasi_size_t len) {
+  struct wasi_ciovec_t vec = { .buf = (const uint8_t *)buf, .buf_len = len };
+  wasi_size_t nwritten = 0;
+  return wasi_fd_write(fd, &vec, 1, &nwritten);
+}
+
+_Noreturn static inline void swift_abort(const char *message) {
+  swift_write(2, message, swift_strlen(message));
+  wasi_proc_exit(1);
+}

test/Macros/lit.local.cfg

@@ -31,3 +31,11 @@ else:
     )
     config.substitutions.append(('%c-flags', config.c_flags))
     config.substitutions.append(('%exe-linker-flags', config.exe_linker_flags))
+
+config.substitutions.insert(
+    0,
+    (
+        '%swift-build-wasm-c-plugin',
+        f'{config.clang} -target wasm32 -nostdlib -iquote %S'
+    )
+)

test/Macros/macro_plugin_wasm.swift

@@ -0,0 +1,60 @@
+// REQUIRES: swift_swift_parser
+// REQUIRES: CODEGENERATOR=WebAssembly
+
+// RUN: %empty-directory(%t)
+
+// RUN: split-file %s %t
+
+//#-- Prepare the Wasm macro plugin.
+// RUN: %swift-build-wasm-c-plugin %t/MacroDefinition.c -o %t/Plugin.wasm
+
+// RUN: env SWIFT_DUMP_PLUGIN_MESSAGING=1 %target-swift-frontend \
+// RUN:   -typecheck \
+// RUN:   -swift-version 5 \
+// RUN:   -load-resolved-plugin %t/Plugin.wasm#%swift-plugin-server#MacroDefinition \
+// RUN:   -Rmacro-loading \
+// RUN:   -module-name MyApp \
+// RUN:   %t/test.swift \
+// RUN:   > %t/macro-loading.txt 2>&1
+
+// RUN: %FileCheck %s < %t/macro-loading.txt
+
+// CHECK: ->(plugin:[[#PID:]]) {"getCapability":{"capability":{"protocolVersion":[[#PROTOCOL_VERSION:]]}}}
+// CHECK: <-(plugin:[[#PID]]) {"getCapabilityResult":{"capability":{"features":["load-plugin-library"],"protocolVersion":7}}}
+// CHECK: ->(plugin:[[#PID]]) {"loadPluginLibrary":{"libraryPath":"{{.*[\\/]}}Plugin.wasm","moduleName":"MacroDefinition"}}
+// CHECK: <-(plugin:[[#PID]]) {"loadPluginLibraryResult":{"diagnostics":[],"loaded":true}}
+// CHECK: ->(plugin:[[#PID]]) {"expandFreestandingMacro":{"discriminator":"$s{{.+}}","lexicalContext":[{{.*}}],"macro":{"moduleName":"MacroDefinition","name":"constInt","typeName":"ConstMacro"},"macroRole":"expression","syntax":{"kind":"expression","location":{"column":16,"fileID":"MyApp/test.swift","fileName":"{{.+}}test.swift","line":4,"offset":143},"source":"#constInt"}}}
+// CHECK: <-(plugin:[[#PID]]) {"expandMacroResult":{"diagnostics":[],"expandedSource":"1"}}
+
+//--- test.swift
+@freestanding(expression) macro constInt() -> Int = #externalMacro(module: "MacroDefinition", type: "ConstMacro")
+
+func foo() {
+  let _: Int = #constInt
+}
+
+//--- MacroDefinition.c
+#include "Inputs/wasi_shim.h"
+
+static void write_json(const char *json) {
+  wasi_size_t len = swift_strlen(json);
+  uint64_t len64 = (uint64_t)len;
+  swift_write(1, &len64, sizeof(len64));
+  swift_write(1, json, len);
+}
+
+int was_start_called = 0;
+int pump_calls = 0;
+
+__attribute__((export_name("_start")))
+void _start(void) {
+  if (was_start_called) swift_abort("_start called twice!");
+  was_start_called = 1;
+}
+
+__attribute__((export_name("swift_wasm_macro_v1_pump")))
+void pump(void) {
+  if (!was_start_called) swift_abort("_start not called!");
+  if (pump_calls++ != 0) swift_abort("expected pump to be called once");
+  write_json("{\"expandMacroResult\": {\"expandedSource\": \"1\", \"diagnostics\": []}}");
+}

test/Macros/macro_plugin_wasm_badversion.swift

@@ -0,0 +1,33 @@
+// REQUIRES: swift_swift_parser
+// REQUIRES: CODEGENERATOR=WebAssembly
+
+// RUN: %empty-directory(%t)
+
+// RUN: split-file %s %t
+
+//#-- Prepare the Wasm macro plugin.
+// RUN: %swift-build-wasm-c-plugin %t/MacroDefinition.c -o %t/Plugin.wasm
+
+// RUN: %target-swift-frontend \
+// RUN:   -typecheck -verify \
+// RUN:   -swift-version 5 \
+// RUN:   -load-resolved-plugin %t/Plugin.wasm#%swift-plugin-server#MacroDefinition \
+// RUN:   -module-name MyApp \
+// RUN:   %t/test.swift
+
+//--- test.swift
+// expected-warning @+2 {{Wasm plugin has an unknown ABI (could not find 'swift_wasm_macro_v1_pump')}}
+// expected-note @+1 {{declared here}}
+@freestanding(expression) macro constInt() -> Int = #externalMacro(module: "MacroDefinition", type: "ConstMacro")
+
+func foo() {
+  // expected-error @+1 {{Wasm plugin has an unknown ABI (could not find 'swift_wasm_macro_v1_pump')}}
+  let _: Int = #constInt
+}
+
+//--- MacroDefinition.c
+__attribute__((export_name("_start")))
+void _start(void) {}
+
+__attribute__((export_name("swift_wasm_macro_v100_pump")))
+void pump(void) {}

test/Macros/macro_plugin_wasm_guest_error.swift

@@ -0,0 +1,40 @@
+// REQUIRES: swift_swift_parser
+// REQUIRES: CODEGENERATOR=WebAssembly
+
+// RUN: %empty-directory(%t)
+
+// RUN: split-file %s %t
+
+//#-- Prepare the Wasm macro plugin.
+// RUN: %swift-build-wasm-c-plugin %t/MacroDefinition.c -o %t/Plugin.wasm
+
+// RUN: %target-swift-frontend \
+// RUN:   -typecheck -verify \
+// RUN:   -swift-version 5 \
+// RUN:   -load-resolved-plugin %t/Plugin.wasm#%swift-plugin-server#MacroDefinition \
+// RUN:   -module-name MyApp \
+// RUN:   %t/test.swift \
+// RUN:   2>%t/macro-loading.txt
+
+// RUN: %FileCheck %s < %t/macro-loading.txt
+
+// CHECK: guest error!
+
+//--- test.swift
+@freestanding(expression) macro constInt() -> Int = #externalMacro(module: "MacroDefinition", type: "ConstMacro")
+
+func foo() {
+  // expected-error @+1 {{failed to communicate with external macro}}
+  let _: Int = #constInt
+}
+
+//--- MacroDefinition.c
+#include "Inputs/wasi_shim.h"
+
+__attribute__((export_name("_start")))
+void _start(void) {}
+
+__attribute__((export_name("swift_wasm_macro_v1_pump")))
+void pump(void) {
+  swift_abort("guest error!\n");
+}

test/Macros/macro_plugin_wasm_nostart.swift

@@ -0,0 +1,33 @@
+// REQUIRES: swift_swift_parser
+// REQUIRES: CODEGENERATOR=WebAssembly
+
+// RUN: %empty-directory(%t)
+
+// RUN: split-file %s %t
+
+//#-- Prepare the Wasm macro plugin.
+// RUN: %swift-build-wasm-c-plugin %t/MacroDefinition.c -o %t/Plugin.wasm
+
+// RUN: %target-swift-frontend \
+// RUN:   -typecheck -verify \
+// RUN:   -swift-version 5 \
+// RUN:   -load-resolved-plugin %t/Plugin.wasm#%swift-plugin-server#MacroDefinition \
+// RUN:   -module-name MyApp \
+// RUN:   %t/test.swift
+
+//--- test.swift
+// expected-warning @+2 {{Wasm plugin does not have a '_start' entrypoint}}
+// expected-note @+1 {{declared here}}
+@freestanding(expression) macro constInt() -> Int = #externalMacro(module: "MacroDefinition", type: "ConstMacro")
+
+func foo() {
+  // expected-error @+1 {{Wasm plugin does not have a '_start' entrypoint}}
+  let _: Int = #constInt
+}
+
+//--- MacroDefinition.c
+__attribute__((export_name("_tart")))
+void _start(void) {}
+
+__attribute__((export_name("swift_wasm_macro_v1_pump")))
+void pump(void) {}

tools/swift-ide-test/swift-ide-test.cpp

@@ -356,7 +356,6 @@ LoadPluginExecutable("load-plugin-executable",
                llvm::cl::desc("load plugin executable"),
                llvm::cl::cat(Category));
 
-
 static llvm::cl::opt<bool>
 EnableSourceImport("enable-source-import", llvm::cl::Hidden,
                    llvm::cl::cat(Category), llvm::cl::init(false));

tools/swift-plugin-server/.editorconfig

@@ -0,0 +1,9 @@
+# editorconfig.org
+
+root = true
+
+[*]
+indent_style = space
+indent_size = 2
+trim_trailing_whitespace = true
+insert_final_newline = true

tools/swift-plugin-server/.gitignore

@@ -0,0 +1 @@
+Package.resolved

tools/swift-plugin-server/.swiftformat

@@ -0,0 +1,3 @@
+--indent 2
+--self insert
+

tools/swift-plugin-server/CMakeLists.txt

@@ -1,11 +1,24 @@
 if (SWIFT_BUILD_SWIFT_SYNTAX)
+  # override the remote SwiftSystem dependency in WasmKit
+  # TODO: create new variables instead of piggybacking off of SWIFT_PATH_TO_SWIFT_SYNTAX_SOURCE
+  file(TO_CMAKE_PATH "${SWIFT_PATH_TO_SWIFT_SYNTAX_SOURCE}" swift_syntax_path)
+  FetchContent_Declare(SwiftSystem SOURCE_DIR "${swift_syntax_path}/../swift-system")
+
+  set(WASMKIT_BUILD_CLI OFF)
+  FetchContent_Declare(WasmKit SOURCE_DIR "${swift_syntax_path}/../wasmkit")
+  FetchContent_MakeAvailable(WasmKit)
+
   add_pure_swift_host_tool(swift-plugin-server
-    Sources/swift-plugin-server/swift-plugin-server.swift
+    Sources/swift-plugin-server/SwiftPluginServer.swift
+    Sources/swift-plugin-server/WasmEngine.swift
+    Sources/swift-plugin-server/WasmKitEngine.swift
+    Sources/swift-plugin-server/WasmMessageHandler.swift
     SWIFT_COMPONENT
       compiler
     SWIFT_DEPENDENCIES
       SwiftCompilerPluginMessageHandling
       SwiftLibraryPluginProvider
+      WasmKitWASI
     PACKAGE_NAME Toolchain
   )
 

tools/swift-plugin-server/Package.swift

@@ -13,13 +13,16 @@ let package = Package(
   ],
   dependencies: [
     .package(path: "../../../swift-syntax"),
+    .package(path: "../../../wasmkit"),
   ],
   targets: [
     .executableTarget(
       name: "swift-plugin-server",
       dependencies: [
         .product(name: "_SwiftCompilerPluginMessageHandling", package: "swift-syntax"),
         .product(name: "_SwiftLibraryPluginProvider", package: "swift-syntax"),
+        .product(name: "WASI", package: "WasmKit"),
+        .product(name: "WasmKitWASI", package: "WasmKit"),
       ]
     ),
     .target(
@@ -29,6 +32,14 @@ let package = Package(
         .product(name: "_SwiftLibraryPluginProvider", package: "swift-syntax"),
       ]
     ),
+    .testTarget(
+      name: "PluginServerTests",
+      dependencies: [
+        .product(name: "WAT", package: "WasmKit"),
+        .product(name: "WasmKit", package: "WasmKit"),
+        "swift-plugin-server",
+      ]
+    ),
   ],
   cxxLanguageStandard: .cxx17
 )