1 //===-- RTDyldMemoryManager.cpp - Memory manager for MC-JIT -----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Implementation of the runtime dynamic memory manager base class.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/ExecutionEngine/RTDyldMemoryManager.h"
15 #include "llvm/Support/DynamicLibrary.h"
16 #include "llvm/Support/ErrorHandling.h"
20 RTDyldMemoryManager::~RTDyldMemoryManager() {}
22 // Determine whether we can register EH tables.
23 #if (defined(__GNUC__) && !defined(__ARM_EABI__) && \
24 !defined(__USING_SJLJ_EXCEPTIONS__))
25 #define HAVE_EHTABLE_SUPPORT 1
27 #define HAVE_EHTABLE_SUPPORT 0
30 #if HAVE_EHTABLE_SUPPORT
31 extern "C" void __register_frame(void*);
33 static const char *processFDE(const char *Entry) {
34 const char *P = Entry;
35 uint32_t Length = *((uint32_t*)P);
37 uint32_t Offset = *((uint32_t*)P);
39 __register_frame((void*)Entry);
44 void RTDyldMemoryManager::registerEHFrames(StringRef SectionData) {
45 #if HAVE_EHTABLE_SUPPORT
46 const char *P = SectionData.data();
47 const char *End = SectionData.data() + SectionData.size();
54 static int jit_noop() {
58 void *RTDyldMemoryManager::getPointerToNamedFunction(const std::string &Name,
59 bool AbortOnFailure) {
60 #if defined(__linux__)
61 //===--------------------------------------------------------------------===//
62 // Function stubs that are invoked instead of certain library calls
64 // Force the following functions to be linked in to anything that uses the
65 // JIT. This is a hack designed to work around the all-too-clever Glibc
66 // strategy of making these functions work differently when inlined vs. when
67 // not inlined, and hiding their real definitions in a separate archive file
68 // that the dynamic linker can't see. For more info, search for
69 // 'libc_nonshared.a' on Google, or read http://llvm.org/PR274.
70 if (Name == "stat") return (void*)(intptr_t)&stat;
71 if (Name == "fstat") return (void*)(intptr_t)&fstat;
72 if (Name == "lstat") return (void*)(intptr_t)&lstat;
73 if (Name == "stat64") return (void*)(intptr_t)&stat64;
74 if (Name == "fstat64") return (void*)(intptr_t)&fstat64;
75 if (Name == "lstat64") return (void*)(intptr_t)&lstat64;
76 if (Name == "atexit") return (void*)(intptr_t)&atexit;
77 if (Name == "mknod") return (void*)(intptr_t)&mknod;
80 // We should not invoke parent's ctors/dtors from generated main()!
81 // On Mingw and Cygwin, the symbol __main is resolved to
82 // callee's(eg. tools/lli) one, to invoke wrong duplicated ctors
83 // (and register wrong callee's dtors with atexit(3)).
84 // We expect ExecutionEngine::runStaticConstructorsDestructors()
85 // is called before ExecutionEngine::runFunctionAsMain() is called.
86 if (Name == "__main") return (void*)(intptr_t)&jit_noop;
88 const char *NameStr = Name.c_str();
89 void *Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr);
92 // If it wasn't found and if it starts with an underscore ('_') character,
93 // try again without the underscore.
94 if (NameStr[0] == '_') {
95 Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr+1);
100 report_fatal_error("Program used external function '" + Name +
101 "' which could not be resolved!");