1 //===----- LinkAllIR.h - Reference All VMCore Code --------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This header file pulls in all the object modules of the VMCore library so 10 // that tools like llc, opt, and lli can ensure they are linked with all symbols 11 // from libVMCore.a It should only be used from a tool's main program. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_LINKALLIR_H 16 #define LLVM_LINKALLIR_H 17 18 #include "llvm/BinaryFormat/Dwarf.h" 19 #include "llvm/IR/InlineAsm.h" 20 #include "llvm/IR/Instructions.h" 21 #include "llvm/IR/LLVMContext.h" 22 #include "llvm/IR/Module.h" 23 #include "llvm/IR/Verifier.h" 24 #include "llvm/Support/DynamicLibrary.h" 25 #include "llvm/Support/MathExtras.h" 26 #include "llvm/Support/Memory.h" 27 #include "llvm/Support/Mutex.h" 28 #include "llvm/Support/Path.h" 29 #include "llvm/Support/Process.h" 30 #include "llvm/Support/Program.h" 31 #include "llvm/Support/Signals.h" 32 #include <cstdlib> 33 34 namespace { 35 struct ForceVMCoreLinking { ForceVMCoreLinkingForceVMCoreLinking36 ForceVMCoreLinking() { 37 // We must reference VMCore in such a way that compilers will not 38 // delete it all as dead code, even with whole program optimization, 39 // yet is effectively a NO-OP. As the compiler isn't smart enough 40 // to know that getenv() never returns -1, this will do the job. 41 if (std::getenv("bar") != (char*) -1) 42 return; 43 llvm::LLVMContext Context; 44 (void)new llvm::Module("", Context); 45 (void)new llvm::UnreachableInst(Context); 46 (void) llvm::createVerifierPass(); 47 } 48 } ForceVMCoreLinking; 49 } 50 51 #endif 52