[cfe-commits] r97133 - in /cfe/trunk/examples: Makefile clang-interpreter/ clang-interpreter/Makefile clang-interpreter/README.txt clang-interpreter/main.cpp
Daniel Dunbar
daniel at zuster.org
Thu Feb 25 00:49:06 PST 2010
Author: ddunbar
Date: Thu Feb 25 02:49:05 2010
New Revision: 97133
URL: http://llvm.org/viewvc/llvm-project?rev=97133&view=rev
Log:
Add a minimal C interpreter example.
- Demonstrates how to build a standalone tool which loads source code using the
Driver and Frontend libraries, and then uses CodeGen and the JIT to actually
execute the code.
- Still more complicated than it should be, but hey its only 153 lines. :)
--
ddunbar at ozzy:tmp$ cat hello.c
#include <stdio.h>
int main() { printf("hello world\n"); return 0; }
ddunbar at ozzy:tmp$ clang-interpreter hello.c
hello world
--
Added:
cfe/trunk/examples/clang-interpreter/
cfe/trunk/examples/clang-interpreter/Makefile
cfe/trunk/examples/clang-interpreter/README.txt
cfe/trunk/examples/clang-interpreter/main.cpp
Modified:
cfe/trunk/examples/Makefile
Modified: cfe/trunk/examples/Makefile
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/examples/Makefile?rev=97133&r1=97132&r2=97133&view=diff
==============================================================================
--- cfe/trunk/examples/Makefile (original)
+++ cfe/trunk/examples/Makefile Thu Feb 25 02:49:05 2010
@@ -9,6 +9,6 @@
LEVEL = ../../..
-PARALLEL_DIRS := PrintFunctionNames wpa
+PARALLEL_DIRS := clang-interpreter PrintFunctionNames wpa
include $(LEVEL)/Makefile.common
Added: cfe/trunk/examples/clang-interpreter/Makefile
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/examples/clang-interpreter/Makefile?rev=97133&view=auto
==============================================================================
--- cfe/trunk/examples/clang-interpreter/Makefile (added)
+++ cfe/trunk/examples/clang-interpreter/Makefile Thu Feb 25 02:49:05 2010
@@ -0,0 +1,28 @@
+##===- examples/clang-interpreter/Makefile -----------------*- Makefile -*-===##
+#
+# The LLVM Compiler Infrastructure
+#
+# This file is distributed under the University of Illinois Open Source
+# License. See LICENSE.TXT for details.
+#
+##===----------------------------------------------------------------------===##
+
+LEVEL = ../../../..
+
+TOOLNAME = clang-interpreter
+CPPFLAGS += -I$(PROJ_SRC_DIR)/../../include -I$(PROJ_OBJ_DIR)/../../include
+NO_INSTALL = 1
+TOOL_NO_EXPORTS = 1
+
+# Include this here so we can get the configuration of the targets that have
+# been configured for construction. We have to do this early so we can set up
+# LINK_COMPONENTS before including Makefile.rules
+include $(LEVEL)/Makefile.config
+
+LINK_COMPONENTS := jit interpreter nativecodegen bitreader bitwriter ipo \
+ selectiondag
+USEDLIBS = clangFrontend.a clangDriver.a clangCodeGen.a clangSema.a \
+ clangChecker.a clangAnalysis.a clangRewrite.a clangAST.a \
+ clangParse.a clangLex.a clangBasic.a
+
+include $(LLVM_SRC_ROOT)/Makefile.rules
Added: cfe/trunk/examples/clang-interpreter/README.txt
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/examples/clang-interpreter/README.txt?rev=97133&view=auto
==============================================================================
--- cfe/trunk/examples/clang-interpreter/README.txt (added)
+++ cfe/trunk/examples/clang-interpreter/README.txt Thu Feb 25 02:49:05 2010
@@ -0,0 +1,17 @@
+This is an example of Clang based interpreter, for executing standalone C
+programs.
+
+It demonstrates the following features:
+ 1. Parsing standard compiler command line arguments using the Driver library.
+
+ 2. Constructing a Clang compiler instance, using the appropriate arguments
+ derived in step #1.
+
+ 3. Invoking the Clang compiler to lex, parse, syntax check, and then generate
+ LLVM code.
+
+ 4. Use the LLVM JIT functionality to execute the final module.
+
+The implementation has many limitations and is not designed to be a full fledged
+C interpreter. It is designed to demonstrate a simple but functional use of the
+Clang compiler libraries.
Added: cfe/trunk/examples/clang-interpreter/main.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/examples/clang-interpreter/main.cpp?rev=97133&view=auto
==============================================================================
--- cfe/trunk/examples/clang-interpreter/main.cpp (added)
+++ cfe/trunk/examples/clang-interpreter/main.cpp Thu Feb 25 02:49:05 2010
@@ -0,0 +1,152 @@
+//===-- examples/clang-interpreter/main.cpp - Clang C Interpreter Example -===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Driver/Compilation.h"
+#include "clang/Driver/Driver.h"
+#include "clang/Driver/Tool.h"
+#include "clang/Frontend/CodeGenAction.h"
+#include "clang/Frontend/CompilerInvocation.h"
+#include "clang/Frontend/CompilerInstance.h"
+#include "clang/Frontend/DiagnosticOptions.h"
+#include "clang/Frontend/FrontendDiagnostic.h"
+#include "clang/Frontend/TextDiagnosticPrinter.h"
+
+#include "llvm/LLVMContext.h"
+#include "llvm/Module.h"
+#include "llvm/Config/config.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/Config/config.h"
+#include "llvm/ExecutionEngine/ExecutionEngine.h"
+#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/System/Host.h"
+#include "llvm/System/Path.h"
+#include "llvm/Target/TargetSelect.h"
+using namespace clang;
+using namespace clang::driver;
+
+llvm::sys::Path GetExecutablePath(const char *Argv0) {
+ // This just needs to be some symbol in the binary; C++ doesn't
+ // allow taking the address of ::main however.
+ void *MainAddr = (void*) (intptr_t) GetExecutablePath;
+ return llvm::sys::Path::GetMainExecutable(Argv0, MainAddr);
+}
+
+int Execute(llvm::Module *Mod, char * const *envp) {
+ llvm::InitializeNativeTarget();
+
+ std::string Error;
+ llvm::OwningPtr<llvm::ExecutionEngine> EE(
+ llvm::ExecutionEngine::createJIT(Mod, &Error));
+ if (!EE) {
+ llvm::errs() << "unable to make execution engine: " << Error << "\n";
+ return 255;
+ }
+
+ llvm::Function *EntryFn = Mod->getFunction("main");
+ if (!EntryFn) {
+ llvm::errs() << "'main' function not found in module.\n";
+ return 255;
+ }
+
+ // FIXME: Support passing arguments.
+ std::vector<std::string> Args;
+ Args.push_back(Mod->getModuleIdentifier());
+
+ return EE->runFunctionAsMain(EntryFn, Args, envp);
+}
+
+int main(int argc, const char **argv, char * const *envp) {
+ void *MainAddr = (void*) (intptr_t) GetExecutablePath;
+ llvm::sys::Path Path = GetExecutablePath(argv[0]);
+ TextDiagnosticPrinter DiagClient(llvm::errs(), DiagnosticOptions());
+
+ Diagnostic Diags(&DiagClient);
+ Driver TheDriver(Path.getBasename(), Path.getDirname(),
+ llvm::sys::getHostTriple(),
+ "a.out", /*IsProduction=*/false, Diags);
+ TheDriver.setTitle("clang interpreter");
+
+ // FIXME: This is a hack to try to force the driver to do something we can
+ // recognize. We need to extend the driver library to support this use model
+ // (basically, exactly one input, and the operation mode is hard wired).
+ llvm::SmallVector<const char *, 16> Args(argv, argv + argc);
+ Args.push_back("-fsyntax-only");
+ llvm::OwningPtr<Compilation> C(TheDriver.BuildCompilation(Args.size(),
+ Args.data()));
+ if (!C)
+ return 0;
+
+ // FIXME: This is copied from ASTUnit.cpp; simplify and eliminate.
+
+ // We expect to get back exactly one command job, if we didn't something
+ // failed. Extract that job from the compilation.
+ const driver::JobList &Jobs = C->getJobs();
+ if (Jobs.size() != 1 || !isa<driver::Command>(Jobs.begin())) {
+ llvm::SmallString<256> Msg;
+ llvm::raw_svector_ostream OS(Msg);
+ C->PrintJob(OS, C->getJobs(), "; ", true);
+ Diags.Report(diag::err_fe_expected_compiler_job) << OS.str();
+ return 1;
+ }
+
+ const driver::Command *Cmd = cast<driver::Command>(*Jobs.begin());
+ if (llvm::StringRef(Cmd->getCreator().getName()) != "clang") {
+ Diags.Report(diag::err_fe_expected_clang_command);
+ return 1;
+ }
+
+ // Initialize a compiler invocation object from the clang (-cc1) arguments.
+ const driver::ArgStringList &CCArgs = Cmd->getArguments();
+ llvm::OwningPtr<CompilerInvocation> CI(new CompilerInvocation);
+ CompilerInvocation::CreateFromArgs(*CI, (const char**) CCArgs.data(),
+ (const char**) CCArgs.data()+CCArgs.size(),
+ Diags);
+
+ // Show the invocation, with -v.
+ if (CI->getHeaderSearchOpts().Verbose) {
+ llvm::errs() << "clang invocation:\n";
+ C->PrintJob(llvm::errs(), C->getJobs(), "\n", true);
+ llvm::errs() << "\n";
+ }
+
+ // FIXME: This is copied from cc1_main.cpp; simplify and eliminate.
+
+ // Create a compiler instance to handle the actual work.
+ CompilerInstance Clang;
+ Clang.setLLVMContext(new llvm::LLVMContext);
+ Clang.setInvocation(CI.take());
+
+ // Create the compilers actual diagnostics engine.
+ Clang.createDiagnostics(int(CCArgs.size()), (char**) CCArgs.data());
+ if (!Clang.hasDiagnostics())
+ return 1;
+
+ // Infer the builtin include path if unspecified.
+ if (Clang.getHeaderSearchOpts().UseBuiltinIncludes &&
+ Clang.getHeaderSearchOpts().ResourceDir.empty())
+ Clang.getHeaderSearchOpts().ResourceDir =
+ CompilerInvocation::GetResourcesPath(argv[0], MainAddr);
+
+ // Create and execute the frontend to generate an LLVM bitcode module.
+ llvm::OwningPtr<CodeGenAction> Act(new EmitLLVMOnlyAction());
+ if (!Clang.ExecuteAction(*Act))
+ return 1;
+
+ int Res = 255;
+ if (llvm::Module *Module = Act->takeModule())
+ Res = Execute(Module, envp);
+
+ // Shutdown.
+
+ llvm::llvm_shutdown();
+
+ return Res;
+}
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