llvm-project/llvm/examples/OrcV2Examples/LLJITWithInitializers/LLJITWithInitializers.cpp

98 lines
2.9 KiB
C++

//===----- LLJITDumpObjects.cpp - How to dump JIT'd objects with LLJIT ----===//
//
// 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
//
//===----------------------------------------------------------------------===//
///
/// \file
///
/// This example demonstrates how to use LLJIT to:
/// - Add absolute symbol definitions.
/// - Run static constructors for a JITDylib.
/// - Run static destructors for a JITDylib.
///
/// This example does not call any functions (e.g. main or equivalent) between
/// running the static constructors and running the static destructors.
///
//===----------------------------------------------------------------------===//
#include "llvm/ADT/StringMap.h"
#include "llvm/ExecutionEngine/Orc/LLJIT.h"
#include "llvm/Support/InitLLVM.h"
#include "llvm/Support/TargetSelect.h"
#include "llvm/Support/raw_ostream.h"
#include "../ExampleModules.h"
using namespace llvm;
using namespace llvm::orc;
ExitOnError ExitOnErr;
const llvm::StringRef ModuleWithInitializer =
R"(
@InitializersRunFlag = external global i32
@DeinitializersRunFlag = external global i32
declare i32 @__cxa_atexit(void (i8*)*, i8*, i8*)
@__dso_handle = external hidden global i8
@llvm.global_ctors =
appending global [1 x { i32, void ()*, i8* }]
[{ i32, void ()*, i8* } { i32 65535, void ()* @init_func, i8* null }]
define internal void @init_func() {
entry:
store i32 1, i32* @InitializersRunFlag
%0 = call i32 @__cxa_atexit(void (i8*)* @deinit_func, i8* null,
i8* @__dso_handle)
ret void
}
define internal void @deinit_func(i8* %0) {
store i32 1, i32* @DeinitializersRunFlag
ret void
}
)";
int main(int argc, char *argv[]) {
// Initialize LLVM.
InitLLVM X(argc, argv);
InitializeNativeTarget();
InitializeNativeTargetAsmPrinter();
cl::ParseCommandLineOptions(argc, argv, "LLJITWithInitializers");
ExitOnErr.setBanner(std::string(argv[0]) + ": ");
auto J = ExitOnErr(LLJITBuilder().create());
auto M = ExitOnErr(parseExampleModule(ModuleWithInitializer, "M"));
// Load the module.
ExitOnErr(J->addIRModule(std::move(M)));
int32_t InitializersRunFlag = 0;
int32_t DeinitializersRunFlag = 0;
ExitOnErr(J->getMainJITDylib().define(absoluteSymbols(
{{J->mangleAndIntern("InitializersRunFlag"),
JITEvaluatedSymbol::fromPointer(&InitializersRunFlag)},
{J->mangleAndIntern("DeinitializersRunFlag"),
JITEvaluatedSymbol::fromPointer(&DeinitializersRunFlag)}})));
// Run static initializers.
ExitOnErr(J->initialize(J->getMainJITDylib()));
// Run deinitializers.
ExitOnErr(J->deinitialize(J->getMainJITDylib()));
outs() << "InitializerRanFlag = " << InitializersRunFlag << "\n"
<< "DeinitializersRunFlag = " << DeinitializersRunFlag << "\n";
return 0;
}