[clang] [clang-repl] Support wasm execution (PR #86402)
Vassil Vassilev via cfe-commits
cfe-commits at lists.llvm.org
Wed Jun 5 00:55:02 PDT 2024
https://github.com/vgvassilev updated https://github.com/llvm/llvm-project/pull/86402
>From e1e3b1ec07133fb67b4f98c6696e330fdedf2460 Mon Sep 17 00:00:00 2001
From: Anubhab Ghosh <anubhabghosh.me at gmail.com>
Date: Sat, 23 Mar 2024 15:13:57 +0000
Subject: [PATCH] [clang-repl] Support wasm execution.
This commit introduces support for running clang-repl and executing C++ code
interactively inside a Javascript engine using WebAssembly when built with
Emscripten. This is achieved by producing WASM "shared libraries" that can be
loaded by the Emscripten runtime using dlopen()
More discussion is available in https://reviews.llvm.org/D158140
---
clang/lib/Interpreter/CMakeLists.txt | 6 +
clang/lib/Interpreter/IncrementalExecutor.cpp | 2 +
clang/lib/Interpreter/IncrementalExecutor.h | 11 +-
clang/lib/Interpreter/Interpreter.cpp | 13 ++
clang/lib/Interpreter/Wasm.cpp | 114 ++++++++++++++++++
clang/lib/Interpreter/Wasm.h | 37 ++++++
6 files changed, 179 insertions(+), 4 deletions(-)
create mode 100644 clang/lib/Interpreter/Wasm.cpp
create mode 100644 clang/lib/Interpreter/Wasm.h
diff --git a/clang/lib/Interpreter/CMakeLists.txt b/clang/lib/Interpreter/CMakeLists.txt
index 9065f998f73c4..6a069659ebb8d 100644
--- a/clang/lib/Interpreter/CMakeLists.txt
+++ b/clang/lib/Interpreter/CMakeLists.txt
@@ -12,6 +12,10 @@ set(LLVM_LINK_COMPONENTS
TargetParser
)
+if (EMSCRIPTEN AND "lld" IN_LIST LLVM_ENABLE_PROJECTS)
+ set(WASM_SRC Wasm.cpp)
+endif()
+
add_clang_library(clangInterpreter
DeviceOffload.cpp
CodeCompletion.cpp
@@ -20,6 +24,8 @@ add_clang_library(clangInterpreter
Interpreter.cpp
InterpreterUtils.cpp
Value.cpp
+ ${WASM_SRC}
+ PARTIAL_SOURCES_INTENDED
DEPENDS
intrinsics_gen
diff --git a/clang/lib/Interpreter/IncrementalExecutor.cpp b/clang/lib/Interpreter/IncrementalExecutor.cpp
index 6f036107c14a9..1824a5b4570a9 100644
--- a/clang/lib/Interpreter/IncrementalExecutor.cpp
+++ b/clang/lib/Interpreter/IncrementalExecutor.cpp
@@ -36,6 +36,8 @@ LLVM_ATTRIBUTE_USED void linkComponents() {
}
namespace clang {
+IncrementalExecutor::IncrementalExecutor(llvm::orc::ThreadSafeContext &TSC)
+ : TSCtx(TSC) {}
llvm::Expected<std::unique_ptr<llvm::orc::LLJITBuilder>>
IncrementalExecutor::createDefaultJITBuilder(
diff --git a/clang/lib/Interpreter/IncrementalExecutor.h b/clang/lib/Interpreter/IncrementalExecutor.h
index b4347209e14fe..7954cde36588b 100644
--- a/clang/lib/Interpreter/IncrementalExecutor.h
+++ b/clang/lib/Interpreter/IncrementalExecutor.h
@@ -43,16 +43,19 @@ class IncrementalExecutor {
llvm::DenseMap<const PartialTranslationUnit *, llvm::orc::ResourceTrackerSP>
ResourceTrackers;
+protected:
+ IncrementalExecutor(llvm::orc::ThreadSafeContext &TSC);
+
public:
enum SymbolNameKind { IRName, LinkerName };
IncrementalExecutor(llvm::orc::ThreadSafeContext &TSC,
llvm::orc::LLJITBuilder &JITBuilder, llvm::Error &Err);
- ~IncrementalExecutor();
+ virtual ~IncrementalExecutor();
- llvm::Error addModule(PartialTranslationUnit &PTU);
- llvm::Error removeModule(PartialTranslationUnit &PTU);
- llvm::Error runCtors() const;
+ virtual llvm::Error addModule(PartialTranslationUnit &PTU);
+ virtual llvm::Error removeModule(PartialTranslationUnit &PTU);
+ virtual llvm::Error runCtors() const;
llvm::Error cleanUp();
llvm::Expected<llvm::orc::ExecutorAddr>
getSymbolAddress(llvm::StringRef Name, SymbolNameKind NameKind) const;
diff --git a/clang/lib/Interpreter/Interpreter.cpp b/clang/lib/Interpreter/Interpreter.cpp
index 683f87e8c8c79..509f3e594568e 100644
--- a/clang/lib/Interpreter/Interpreter.cpp
+++ b/clang/lib/Interpreter/Interpreter.cpp
@@ -15,6 +15,9 @@
#include "IncrementalExecutor.h"
#include "IncrementalParser.h"
#include "InterpreterUtils.h"
+#ifdef __EMSCRIPTEN__
+#include "Wasm.h"
+#endif // __EMSCRIPTEN__
#include "clang/AST/ASTContext.h"
#include "clang/AST/Mangle.h"
@@ -183,6 +186,12 @@ IncrementalCompilerBuilder::CreateCpp() {
std::vector<const char *> Argv;
Argv.reserve(5 + 1 + UserArgs.size());
Argv.push_back("-xc++");
+#ifdef __EMSCRIPTEN__
+ Argv.push_back("-target");
+ Argv.push_back("wasm32-unknown-emscripten");
+ Argv.push_back("-pie");
+ Argv.push_back("-shared");
+#endif
Argv.insert(Argv.end(), UserArgs.begin(), UserArgs.end());
std::string TT = TargetTriple ? *TargetTriple : llvm::sys::getProcessTriple();
@@ -423,8 +432,12 @@ llvm::Error Interpreter::CreateExecutor() {
}
llvm::Error Err = llvm::Error::success();
+#ifdef __EMSCRIPTEN__
+ auto Executor = std::make_unique<WasmIncrementalExecutor>(*TSCtx);
+#else
auto Executor =
std::make_unique<IncrementalExecutor>(*TSCtx, *JITBuilder, Err);
+#endif
if (!Err)
IncrExecutor = std::move(Executor);
diff --git a/clang/lib/Interpreter/Wasm.cpp b/clang/lib/Interpreter/Wasm.cpp
new file mode 100644
index 0000000000000..1001410aa0f27
--- /dev/null
+++ b/clang/lib/Interpreter/Wasm.cpp
@@ -0,0 +1,114 @@
+//===----------------- Wasm.cpp - Wasm Interpreter --------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements interpreter support for code execution in WebAssembly.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Wasm.h"
+#include "IncrementalExecutor.h"
+
+#include <llvm/IR/LegacyPassManager.h>
+#include <llvm/IR/Module.h>
+#include <llvm/MC/TargetRegistry.h>
+#include <llvm/Target/TargetMachine.h>
+
+#include <clang/Interpreter/Interpreter.h>
+
+#include <string>
+
+namespace lld {
+namespace wasm {
+bool link(llvm::ArrayRef<const char *> args, llvm::raw_ostream &stdoutOS,
+ llvm::raw_ostream &stderrOS, bool exitEarly, bool disableOutput);
+} // namespace wasm
+} // namespace lld
+
+#include <dlfcn.h>
+
+namespace clang {
+
+WasmIncrementalExecutor::WasmIncrementalExecutor(
+ llvm::orc::ThreadSafeContext &TSC)
+ : IncrementalExecutor(TSC) {}
+
+llvm::Error WasmIncrementalExecutor::addModule(PartialTranslationUnit &PTU) {
+ std::string ErrorString;
+
+ const llvm::Target *Target = llvm::TargetRegistry::lookupTarget(
+ PTU.TheModule->getTargetTriple(), ErrorString);
+ if (!Target) {
+ return llvm::make_error<llvm::StringError>("Failed to create Wasm Target: ",
+ llvm::inconvertibleErrorCode());
+ }
+
+ llvm::TargetOptions TO = llvm::TargetOptions();
+ llvm::TargetMachine *TargetMachine = Target->createTargetMachine(
+ PTU.TheModule->getTargetTriple(), "", "", TO, llvm::Reloc::Model::PIC_);
+ PTU.TheModule->setDataLayout(TargetMachine->createDataLayout());
+ std::string OutputFileName = PTU.TheModule->getName().str() + ".wasm";
+
+ std::error_code Error;
+ llvm::raw_fd_ostream OutputFile(llvm::StringRef(OutputFileName), Error);
+
+ llvm::legacy::PassManager PM;
+ if (TargetMachine->addPassesToEmitFile(PM, OutputFile, nullptr,
+ llvm::CodeGenFileType::ObjectFile)) {
+ return llvm::make_error<llvm::StringError>(
+ "Wasm backend cannot produce object.", llvm::inconvertibleErrorCode());
+ }
+
+ if (!PM.run(*PTU.TheModule)) {
+
+ return llvm::make_error<llvm::StringError>("Failed to emit Wasm object.",
+ llvm::inconvertibleErrorCode());
+ }
+
+ OutputFile.close();
+
+ std::vector<const char *> LinkerArgs = {"wasm-ld",
+ "-pie",
+ "--import-memory",
+ "--no-entry",
+ "--export-all",
+ "--experimental-pic",
+ "--no-export-dynamic",
+ "--stack-first",
+ OutputFileName.c_str(),
+ "-o",
+ OutputFileName.c_str()};
+ int Result =
+ lld::wasm::link(LinkerArgs, llvm::outs(), llvm::errs(), false, false);
+ if (!Result)
+ return llvm::make_error<llvm::StringError>(
+ "Failed to link incremental module", llvm::inconvertibleErrorCode());
+
+ void *LoadedLibModule =
+ dlopen(OutputFileName.c_str(), RTLD_NOW | RTLD_GLOBAL);
+ if (LoadedLibModule == nullptr) {
+ llvm::errs() << dlerror() << '\n';
+ return llvm::make_error<llvm::StringError>(
+ "Failed to load incremental module", llvm::inconvertibleErrorCode());
+ }
+
+ return llvm::Error::success();
+}
+
+llvm::Error WasmIncrementalExecutor::removeModule(PartialTranslationUnit &PTU) {
+ return llvm::make_error<llvm::StringError>("Not implemented yet",
+ llvm::inconvertibleErrorCode());
+}
+
+llvm::Error WasmIncrementalExecutor::runCtors() const {
+ // This seems to be automatically done when using dlopen()
+ return llvm::Error::success();
+}
+
+WasmIncrementalExecutor::~WasmIncrementalExecutor() = default;
+
+} // namespace clang
diff --git a/clang/lib/Interpreter/Wasm.h b/clang/lib/Interpreter/Wasm.h
new file mode 100644
index 0000000000000..b1fd88024f14d
--- /dev/null
+++ b/clang/lib/Interpreter/Wasm.h
@@ -0,0 +1,37 @@
+//===------------------ Wasm.h - Wasm Interpreter ---------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements interpreter support for code execution in WebAssembly.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_INTERPRETER_WASM_H
+#define LLVM_CLANG_LIB_INTERPRETER_WASM_H
+
+#ifndef __EMSCRIPTEN__
+#error "This requires emscripten."
+#endif // __EMSCRIPTEN__
+
+#include "IncrementalExecutor.h"
+
+namespace clang {
+
+class WasmIncrementalExecutor : public IncrementalExecutor {
+public:
+ WasmIncrementalExecutor(llvm::orc::ThreadSafeContext &TSC);
+
+ llvm::Error addModule(PartialTranslationUnit &PTU) override;
+ llvm::Error removeModule(PartialTranslationUnit &PTU) override;
+ llvm::Error runCtors() const override;
+
+ ~WasmIncrementalExecutor() override;
+};
+
+} // namespace clang
+
+#endif // LLVM_CLANG_LIB_INTERPRETER_WASM_H
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