LLVM 17.0.0git
RTDyldMemoryManager.cpp
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1//===-- RTDyldMemoryManager.cpp - Memory manager for MC-JIT -----*- 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// Implementation of the runtime dynamic memory manager base class.
10//
11//===----------------------------------------------------------------------===//
12
13#include "llvm/Config/config.h"
18#include <cstdlib>
19
20#ifdef __linux__
21 // These includes used by RTDyldMemoryManager::getPointerToNamedFunction()
22 // for Glibc trickery. See comments in this function for more information.
23 #ifdef HAVE_SYS_STAT_H
24 #include <sys/stat.h>
25 #endif
26 #include <fcntl.h>
27 #include <unistd.h>
28#endif
29
30namespace llvm {
31
33
34#if defined(HAVE_REGISTER_FRAME) && defined(HAVE_DEREGISTER_FRAME) && \
35 !defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__)
36extern "C" void __register_frame(void *);
37extern "C" void __deregister_frame(void *);
38#else
39// The building compiler does not have __(de)register_frame but
40// it may be found at runtime in a dynamically-loaded library.
41// For example, this happens when building LLVM with Visual C++
42// but using the MingW runtime.
43static void __register_frame(void *p) {
44 static bool Searched = false;
45 static void((*rf)(void *)) = 0;
46
47 if (!Searched) {
48 Searched = true;
49 *(void **)&rf =
51 }
52 if (rf)
53 rf(p);
54}
55
56static void __deregister_frame(void *p) {
57 static bool Searched = false;
58 static void((*df)(void *)) = 0;
59
60 if (!Searched) {
61 Searched = true;
63 "__deregister_frame");
64 }
65 if (df)
66 df(p);
67}
68#endif
69
70/* libgcc and libunwind __register_frame behave differently. We use the presence
71 * of __unw_add_dynamic_fde to detect libunwind. */
72#if defined(HAVE_UNW_ADD_DYNAMIC_FDE) || defined(__APPLE__)
73
74static const char *processFDE(const char *Entry, bool isDeregister) {
75 const char *P = Entry;
76 uint32_t Length = *((const uint32_t *)P);
77 P += 4;
78 uint32_t Offset = *((const uint32_t *)P);
79 if (Offset != 0) {
80 if (isDeregister)
81 __deregister_frame(const_cast<char *>(Entry));
82 else
83 __register_frame(const_cast<char *>(Entry));
84 }
85 return P + Length;
86}
87
88// This implementation handles frame registration for local targets.
89// Memory managers for remote targets should re-implement this function
90// and use the LoadAddr parameter.
92 size_t Size) {
93 // On OS X OS X __register_frame takes a single FDE as an argument.
94 // See http://lists.llvm.org/pipermail/llvm-dev/2013-April/061737.html
95 // and projects/libunwind/src/UnwindLevel1-gcc-ext.c.
96 const char *P = (const char *)Addr;
97 const char *End = P + Size;
98 while (P != End)
99 P = processFDE(P, false);
100}
101
103 size_t Size) {
104 const char *P = (const char *)Addr;
105 const char *End = P + Size;
106 while (P != End)
107 P = processFDE(P, true);
108}
109
110#else
111
113 size_t Size) {
114 // On Linux __register_frame takes a single argument:
115 // a pointer to the start of the .eh_frame section.
116
117 // How can it find the end? Because crtendS.o is linked
118 // in and it has an .eh_frame section with four zero chars.
120}
121
123 size_t Size) {
125}
126
127#endif
128
130 size_t Size) {
132 EHFrames.push_back({Addr, Size});
133}
134
136 for (auto &Frame : EHFrames)
137 deregisterEHFramesInProcess(Frame.Addr, Frame.Size);
138 EHFrames.clear();
139}
140
141static int jit_noop() {
142 return 0;
143}
144
145// ARM math functions are statically linked on Android from libgcc.a, but not
146// available at runtime for dynamic linking. On Linux these are usually placed
147// in libgcc_s.so so can be found by normal dynamic lookup.
148#if defined(__BIONIC__) && defined(__arm__)
149// List of functions which are statically linked on Android and can be generated
150// by LLVM. This is done as a nested macro which is used once to declare the
151// imported functions with ARM_MATH_DECL and once to compare them to the
152// user-requested symbol in getSymbolAddress with ARM_MATH_CHECK. The test
153// assumes that all functions start with __aeabi_ and getSymbolAddress must be
154// modified if that changes.
155#define ARM_MATH_IMPORTS(PP) \
156 PP(__aeabi_d2f) \
157 PP(__aeabi_d2iz) \
158 PP(__aeabi_d2lz) \
159 PP(__aeabi_d2uiz) \
160 PP(__aeabi_d2ulz) \
161 PP(__aeabi_dadd) \
162 PP(__aeabi_dcmpeq) \
163 PP(__aeabi_dcmpge) \
164 PP(__aeabi_dcmpgt) \
165 PP(__aeabi_dcmple) \
166 PP(__aeabi_dcmplt) \
167 PP(__aeabi_dcmpun) \
168 PP(__aeabi_ddiv) \
169 PP(__aeabi_dmul) \
170 PP(__aeabi_dsub) \
171 PP(__aeabi_f2d) \
172 PP(__aeabi_f2iz) \
173 PP(__aeabi_f2lz) \
174 PP(__aeabi_f2uiz) \
175 PP(__aeabi_f2ulz) \
176 PP(__aeabi_fadd) \
177 PP(__aeabi_fcmpeq) \
178 PP(__aeabi_fcmpge) \
179 PP(__aeabi_fcmpgt) \
180 PP(__aeabi_fcmple) \
181 PP(__aeabi_fcmplt) \
182 PP(__aeabi_fcmpun) \
183 PP(__aeabi_fdiv) \
184 PP(__aeabi_fmul) \
185 PP(__aeabi_fsub) \
186 PP(__aeabi_i2d) \
187 PP(__aeabi_i2f) \
188 PP(__aeabi_idiv) \
189 PP(__aeabi_idivmod) \
190 PP(__aeabi_l2d) \
191 PP(__aeabi_l2f) \
192 PP(__aeabi_lasr) \
193 PP(__aeabi_ldivmod) \
194 PP(__aeabi_llsl) \
195 PP(__aeabi_llsr) \
196 PP(__aeabi_lmul) \
197 PP(__aeabi_ui2d) \
198 PP(__aeabi_ui2f) \
199 PP(__aeabi_uidiv) \
200 PP(__aeabi_uidivmod) \
201 PP(__aeabi_ul2d) \
202 PP(__aeabi_ul2f) \
203 PP(__aeabi_uldivmod)
204
205// Declare statically linked math functions on ARM. The function declarations
206// here do not have the correct prototypes for each function in
207// ARM_MATH_IMPORTS, but it doesn't matter because only the symbol addresses are
208// needed. In particular the __aeabi_*divmod functions do not have calling
209// conventions which match any C prototype.
210#define ARM_MATH_DECL(name) extern "C" void name();
211ARM_MATH_IMPORTS(ARM_MATH_DECL)
212#undef ARM_MATH_DECL
213#endif
214
215#if defined(__linux__) && defined(__GLIBC__) && \
216 (defined(__i386__) || defined(__x86_64__))
217extern "C" LLVM_ATTRIBUTE_WEAK void __morestack();
218#endif
219
222 // This implementation assumes that the host program is the target.
223 // Clients generating code for a remote target should implement their own
224 // memory manager.
225#if defined(__linux__) && defined(__GLIBC__)
226 //===--------------------------------------------------------------------===//
227 // Function stubs that are invoked instead of certain library calls
228 //
229 // Force the following functions to be linked in to anything that uses the
230 // JIT. This is a hack designed to work around the all-too-clever Glibc
231 // strategy of making these functions work differently when inlined vs. when
232 // not inlined, and hiding their real definitions in a separate archive file
233 // that the dynamic linker can't see. For more info, search for
234 // 'libc_nonshared.a' on Google, or read http://llvm.org/PR274.
235 if (Name == "stat") return (uint64_t)&stat;
236 if (Name == "fstat") return (uint64_t)&fstat;
237 if (Name == "lstat") return (uint64_t)&lstat;
238 if (Name == "stat64") return (uint64_t)&stat64;
239 if (Name == "fstat64") return (uint64_t)&fstat64;
240 if (Name == "lstat64") return (uint64_t)&lstat64;
241 if (Name == "atexit") return (uint64_t)&atexit;
242 if (Name == "mknod") return (uint64_t)&mknod;
243
244#if defined(__i386__) || defined(__x86_64__)
245 // __morestack lives in libgcc, a static library.
246 if (&__morestack && Name == "__morestack")
247 return (uint64_t)&__morestack;
248#endif
249#endif // __linux__ && __GLIBC__
250
251 // See ARM_MATH_IMPORTS definition for explanation
252#if defined(__BIONIC__) && defined(__arm__)
253 if (Name.compare(0, 8, "__aeabi_") == 0) {
254 // Check if the user has requested any of the functions listed in
255 // ARM_MATH_IMPORTS, and if so redirect to the statically linked symbol.
256#define ARM_MATH_CHECK(fn) if (Name == #fn) return (uint64_t)&fn;
257 ARM_MATH_IMPORTS(ARM_MATH_CHECK)
258#undef ARM_MATH_CHECK
259 }
260#endif
261
262 // We should not invoke parent's ctors/dtors from generated main()!
263 // On Mingw and Cygwin, the symbol __main is resolved to
264 // callee's(eg. tools/lli) one, to invoke wrong duplicated ctors
265 // (and register wrong callee's dtors with atexit(3)).
266 // We expect ExecutionEngine::runStaticConstructorsDestructors()
267 // is called before ExecutionEngine::runFunctionAsMain() is called.
268 if (Name == "__main") return (uint64_t)&jit_noop;
269
270 const char *NameStr = Name.c_str();
271
272 // DynamicLibrary::SearchForAddresOfSymbol expects an unmangled 'C' symbol
273 // name so ff we're on Darwin, strip the leading '_' off.
274#ifdef __APPLE__
275 if (NameStr[0] == '_')
276 ++NameStr;
277#endif
278
280}
281
283 bool AbortOnFailure) {
285
286 if (!Addr && AbortOnFailure)
287 report_fatal_error(Twine("Program used external function '") + Name +
288 "' which could not be resolved!");
289
290 return (void*)Addr;
291}
292
293void RTDyldMemoryManager::anchor() {}
294void MCJITMemoryManager::anchor() {}
295} // namespace llvm
#define LLVM_ATTRIBUTE_WEAK
Definition: Compiler.h:180
uint64_t Addr
std::string Name
uint64_t Size
#define P(N)
static void deregisterEHFramesInProcess(uint8_t *Addr, size_t Size)
Deregister EH frames in the current proces.
void registerEHFrames(uint8_t *Addr, uint64_t LoadAddr, size_t Size) override
Register the EH frames with the runtime so that c++ exceptions work.
virtual void * getPointerToNamedFunction(const std::string &Name, bool AbortOnFailure=true)
This method returns the address of the specified function.
virtual uint64_t getSymbolAddress(const std::string &Name)
Legacy symbol lookup - DEPRECATED! Please override findSymbol instead.
static uint64_t getSymbolAddressInProcess(const std::string &Name)
This method returns the address of the specified function or variable in the current process.
static void registerEHFramesInProcess(uint8_t *Addr, size_t Size)
Register EH frames in the current process.
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
static void * SearchForAddressOfSymbol(const char *symbolName)
This function will search through all previously loaded dynamic libraries for the symbol symbolName.
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
@ Offset
Definition: DWP.cpp:406
@ Length
Definition: DWP.cpp:406
static int jit_noop()
void report_fatal_error(Error Err, bool gen_crash_diag=true)
Report a serious error, calling any installed error handler.
Definition: Error.cpp:145
void __register_frame(void *)
void __deregister_frame(void *)