[WASM] Add ILStrip task to wasm app build process

docs/workflow/building/mono/README.md

@@ -66,7 +66,7 @@ For `build.sh`
 
 `/p:DisableCrossgen=true` - Skips building the installer if you don't need it (builds faster)
 
-`-p:KeepNativeSymbols=true` - Keep the symbols in the binary instead of stripping them out to a separate file. This helps with debugging Mono with lldb.
+`/p:KeepNativeSymbols=true` - Keep the symbols in the binary instead of stripping them out to a separate file. This helps with debugging Mono with lldb.
 
 The build has a number of options that you can learn about using build -?.
 

src/libraries/tests.proj

@@ -371,6 +371,13 @@
     <ProjectExclusions Include="$(MSBuildThisFileDirectory)System.Net.WebSockets.Client\tests\System.Net.WebSockets.Client.Tests.csproj" />
   </ItemGroup>
 
+  <!-- Test WASM with WASMStripIL enabled -->
+  <ItemGroup Condition="'$(TargetOS)' == 'browser' and '$(RunAOTCompilation)' == 'true'">
+    <SmokeTestProject Include="$(RepoRoot)\src\tests\FunctionalTests\WebAssembly\Browser\StartupHook\WebAssembly.Browser.StartupHook.Test.csproj"
+                      AdditionalProperties="%(AdditionalProperties);WASMStripIL=true;TestProjectName=WebAssembly_Browser_StartupHook_Test_ILStripped"
+                      BuildInParallel="false" />
+  </ItemGroup>
+
   <!-- Aggressive Trimming related failures -->
   <ItemGroup Condition="('$(TargetOS)' != 'browser' and '$(RunAOTCompilation)' == 'true' and '$(MonoForceInterpreter)' != 'true') or ('$(TargetOS)' == 'browser' and '$(BuildAOTTestsOnHelix)' == 'true' and '$(RunDisabledWasmTests)' != 'true')">
   </ItemGroup>

src/mono/mono/mini/aot-compiler.c

@@ -9832,7 +9832,7 @@ compile_method (MonoAotCompile *acfg, MonoMethod *method)
 	mono_atomic_inc_i32 (&acfg->stats.ccount);
 
 	if (acfg->aot_opts.compiled_methods_outfile && acfg->compiled_methods_outfile != NULL) {
-		if (!mono_method_is_generic_impl (method) && method->token != 0) {
+		if (!mono_method_is_generic_impl (method) && method->token != 0 && !cfg->deopt && !cfg->interp_entry_only && mini_get_interp_callbacks ()->jit_call_can_be_supported (method, mono_method_signature_internal (method))) {
 			fprintf (acfg->compiled_methods_outfile, "%x\n", method->token);
 		}
 	}

src/mono/mono/mini/ee.h

@@ -65,6 +65,7 @@ typedef gpointer MonoInterpFrameHandle;
 	MONO_EE_CALLBACK (void, entry_llvmonly, (gpointer res, gpointer *args, gpointer imethod)) \
 	MONO_EE_CALLBACK (gpointer, get_interp_method, (MonoMethod *method)) \
 	MONO_EE_CALLBACK (MonoJitInfo*, compile_interp_method, (MonoMethod *method, MonoError *error)) \
+	MONO_EE_CALLBACK (gboolean, jit_call_can_be_supported, (MonoMethod *method, MonoMethodSignature *sig)) \
 
 typedef struct _MonoEECallbacks {
 

src/mono/mono/mini/interp-stubs.c

@@ -252,6 +252,12 @@ stub_compile_interp_method (MonoMethod *method, MonoError *error)
 	return NULL;
 }
 
+static gboolean
+stub_jit_call_can_be_supported (MonoMethod *method, MonoMethodSignature *sig)
+{
+	return TRUE;
+}
+
 #undef MONO_EE_CALLBACK
 #define MONO_EE_CALLBACK(ret, name, sig) stub_ ## name,
 

src/mono/mono/mini/interp/interp-internals.h

@@ -320,6 +320,9 @@ mono_mint_type (MonoType *type);
 int
 mono_interp_type_size (MonoType *type, int mt, int *align_p);
 
+gboolean
+interp_jit_call_can_be_supported (MonoMethod *method, MonoMethodSignature *sig);
+
 #if HOST_BROWSER
 
 gboolean

src/mono/mono/mini/interp/interp.c

@@ -4055,7 +4055,39 @@ mono_interp_exec_method (InterpFrame *frame, ThreadContext *context, FrameClause
 			}
 			ip += 5;
 
-			goto call;
+			InterpMethodCodeType code_type = cmethod->code_type;
+
+			g_assert (code_type == IMETHOD_CODE_UNKNOWN ||
+			          code_type == IMETHOD_CODE_INTERP ||
+			          code_type == IMETHOD_CODE_COMPILED);
+
+			if (G_UNLIKELY (code_type == IMETHOD_CODE_UNKNOWN)) {
+				// FIXME push/pop LMF
+				MonoMethodSignature *sig = mono_method_signature_internal (cmethod->method);
+				if (mono_interp_jit_call_supported (cmethod->method, sig))
+					code_type = IMETHOD_CODE_COMPILED;
+				else
+					code_type = IMETHOD_CODE_INTERP;
+				cmethod->code_type = code_type;
+			}
+
+			if (code_type == IMETHOD_CODE_INTERP) {
+
+				goto call;
+
+			} else if (code_type == IMETHOD_CODE_COMPILED) {
+				frame->state.ip = ip;
+				error_init_reuse (error);
+				do_jit_call (context, (stackval*)(locals + return_offset), (stackval*)(locals + call_args_offset), frame, cmethod, error);
+				if (!is_ok (error)) {
+					MonoException *call_ex = interp_error_convert_to_exception (frame, error, ip);
+					THROW_EX (call_ex, ip);
+				}
+
+				CHECK_RESUME_STATE (context);
+			}
+
+			MINT_IN_BREAK;
 		}
 		MINT_IN_CASE(MINT_CALLI) {
 			gboolean need_unbox;
@@ -8569,6 +8601,31 @@ interp_sufficient_stack (gsize size)
 	return (context->stack_pointer + size) < (context->stack_start + INTERP_STACK_SIZE);
 }
 
+gboolean
+interp_jit_call_can_be_supported (MonoMethod *method, MonoMethodSignature *sig)
+{
+	if (sig->param_count > 10)
+		return FALSE;
+	if (sig->pinvoke)
+		return FALSE;
+	if (method->flags & METHOD_ATTRIBUTE_PINVOKE_IMPL)
+		return FALSE;
+	if (method->iflags & METHOD_IMPL_ATTRIBUTE_INTERNAL_CALL)
+		return FALSE;
+	if (!mono_llvm_only && method->is_inflated)
+		return FALSE;
+	if (method->string_ctor)
+		return FALSE;
+	if (method->wrapper_type != MONO_WRAPPER_NONE)
+		return FALSE;
+
+	if (method->flags & METHOD_ATTRIBUTE_REQSECOBJ)
+		/* Used to mark methods containing StackCrawlMark locals */
+		return FALSE;
+
+	return TRUE;
+}
+
 static void
 interp_cleanup (void)
 {

src/mono/mono/mini/interp/transform.c

@@ -1213,23 +1213,7 @@ mono_interp_jit_call_supported (MonoMethod *method, MonoMethodSignature *sig)
 {
 	GSList *l;
 
-	if (sig->param_count > 10)
-		return FALSE;
-	if (sig->pinvoke)
-		return FALSE;
-	if (method->flags & METHOD_ATTRIBUTE_PINVOKE_IMPL)
-		return FALSE;
-	if (method->iflags & METHOD_IMPL_ATTRIBUTE_INTERNAL_CALL)
-		return FALSE;
-	if (!mono_llvm_only && method->is_inflated)
-		return FALSE;
-	if (method->string_ctor)
-		return FALSE;
-	if (method->wrapper_type != MONO_WRAPPER_NONE)
-		return FALSE;
-
-	if (method->flags & METHOD_ATTRIBUTE_REQSECOBJ)
-		/* Used to mark methods containing StackCrawlMark locals */
+	if (!interp_jit_call_can_be_supported (method, sig))
 		return FALSE;
 
 	if (mono_aot_only && m_class_get_image (method->klass)->aot_module && !(method->iflags & METHOD_IMPL_ATTRIBUTE_SYNCHRONIZED)) {
@@ -2982,6 +2966,10 @@ interp_inline_method (TransformData *td, MonoMethod *target_method, MonoMethodHe
 	int nargs = csignature->param_count + !!csignature->hasthis;
 	InterpInst *prev_last_ins;
 
+	if (header->code_size == 0)
+		/* IL stripped */
+		return FALSE;
+
 	if (csignature->is_inflated)
 		generic_context = mono_method_get_context (target_method);
 	else {

src/mono/wasm/build/WasmApp.InTree.targets

@@ -1,6 +1,7 @@
 <Project>
   <!-- This depends on the root Directory.Build.targets imported this file -->
   <UsingTask TaskName="MonoAOTCompiler" AssemblyFile="$(MonoAOTCompilerTasksAssemblyPath)" />
+  <UsingTask TaskName="ILStrip" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" />
   <UsingTask TaskName="RuntimeConfigParserTask" AssemblyFile="$(MonoTargetsTasksAssemblyPath)" />
 
   <!-- TODO: this breaks runtime tests on Helix due to the file not being there for some reason. Once this is fixed we can remove the UpdateRuntimePack target here -->

src/mono/wasm/build/WasmApp.Native.targets

@@ -674,12 +674,25 @@
       CacheFilePath="$(_AOTCompilerCacheFile)"
       LLVMDebug="dwarfdebug"
       LLVMPath="$(EmscriptenUpstreamBinPath)"
+      CollectCompiledMethods="$(WASMStripIL)"
+      CompiledMethodsOutputDirectory="$(_WasmIntermediateOutputPath)tokens"
       IntermediateOutputPath="$(_WasmIntermediateOutputPath)"
       AotProfilePath="@(AotProfilePath)">
 
       <Output TaskParameter="CompiledAssemblies" ItemName="_WasmAssembliesInternal" />
       <Output TaskParameter="FileWrites" ItemName="FileWrites" />
     </MonoAOTCompiler>
+    <ILStrip
+        Condition=" '$(WASMStripIL)' == 'true' "
+        TrimIndividualMethods="true"
+        Assemblies="@(_WasmAssembliesInternal)">
+      <Output TaskParameter="TrimmedAssemblies" ItemName="_ILStripTrimmedAssemblies" />
+    </ILStrip>
+    <Move
+        Condition=" '$(WASMStripIL)' == 'true' "
+        SourceFiles="@(_ILStripTrimmedAssemblies->'%(TrimmedAssemblyFileName)')"
+        DestinationFiles="@(_ILStripTrimmedAssemblies)"
+    />
 
     <ItemGroup>
       <_BitcodeFile Include="%(_WasmAssembliesInternal.LlvmBitcodeFile)" />

src/mono/wasm/build/WasmApp.targets

@@ -85,6 +85,7 @@
                                               - AppBundle directly contains user files
                                               - AppBundle/_framework contains generated files (dlls, runtime scripts, icu)
                                               - AppBundle/_content contains web files from nuget packages (css, js, etc)
+      - $(WASMStripIL)                      - Set to true to enable trimming away AOT compiled methods body (IL code)
 
       Public items:
       - @(WasmExtraFilesToDeploy) - Files to copy to $(WasmAppDir).
@@ -144,6 +145,9 @@
     <!-- by default, package assemblies as webcil -->
     <WasmEnableWebcil Condition="'$(WasmEnableWebcil)' == ''">true</WasmEnableWebcil>
 
+    <!-- by default, method body IL code trimming is disabled -->
+    <WASMStripIL Condition="'$(WASMStripIL)' == ''">false</WASMStripIL>
+
     <WasmRuntimeAssetsLocation Condition="'$(WasmRuntimeAssetsLocation)' == ''">_framework</WasmRuntimeAssetsLocation>
   </PropertyGroup>
 

src/tasks/MonoTargetsTasks/ILStrip/ILStrip.cs

@@ -116,6 +116,7 @@ private bool StripAssembly(ITaskItem assemblyItem)
 
     private bool TrimMethods(ITaskItem assemblyItem)
     {
+        string assemblyFilePathArg = assemblyItem.ItemSpec;
         string methodTokenFile = assemblyItem.GetMetadata("MethodTokenFile");
         if (string.IsNullOrEmpty(methodTokenFile))
         {
@@ -165,7 +166,7 @@ private bool TrimMethods(ITaskItem assemblyItem)
 
         if (isTrimmed)
         {
-            AddItemToTrimmedList(assemblyFilePath, trimmedAssemblyFilePath);
+            AddItemToTrimmedList(assemblyFilePathArg, trimmedAssemblyFilePath);
         }
 
         return true;
@@ -252,6 +253,8 @@ private void CreateTrimmedAssembly(PEReader peReader, string trimmedAssemblyFile
                     int methodSize = ComputeMethodSize(peReader, rva);
                     int actualLoc = ComputeMethodHash(peReader, rva);
                     int headerSize = ComputeMethodHeaderSize(memStream, actualLoc);
+                    if (headerSize == 1) //Set code size to zero for TinyFormat
+                        SetCodeSizeToZeroForTiny(ref memStream, actualLoc);
                     ZeroOutMethodBody(ref memStream, methodSize, actualLoc, headerSize);
                 }
                 else if (count < 0)
@@ -282,6 +285,13 @@ private static int ComputeMethodHeaderSize(MemoryStream memStream, int actualLoc
         return (headerFlag == 2 ? 1 : 4);
     }
 
+    private static void SetCodeSizeToZeroForTiny(ref MemoryStream memStream, int actualLoc)
+    {
+        memStream.Position = actualLoc;
+        byte[] header = {0b10};
+        memStream.Write(header, 0, 1);
+    }
+
     private static void ZeroOutMethodBody(ref MemoryStream memStream, int methodSize, int actualLoc, int headerSize)
     {
         memStream.Position = actualLoc + headerSize;