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diff --git a/lib/ExecutionEngine/JIT/JITDebugRegisterer.cpp b/lib/ExecutionEngine/JIT/JITDebugRegisterer.cpp
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-//===-- JITDebugRegisterer.cpp - Register debug symbols for JIT -----------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file defines a JITDebugRegisterer object that is used by the JIT to
-// register debug info with debuggers like GDB.
-//
-//===----------------------------------------------------------------------===//
-
-#include "JITDebugRegisterer.h"
-#include "../../CodeGen/ELF.h"
-#include "../../CodeGen/ELFWriter.h"
-#include "llvm/LLVMContext.h"
-#include "llvm/Function.h"
-#include "llvm/Module.h"
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetOptions.h"
-#include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/OwningPtr.h"
-#include "llvm/Support/Compiler.h"
-#include "llvm/Support/MutexGuard.h"
-#include "llvm/Support/raw_ostream.h"
-#include "llvm/Support/Mutex.h"
-#include <string>
-
-namespace llvm {
-
-// This must be kept in sync with gdb/gdb/jit.h .
-extern "C" {
-
- // Debuggers puts a breakpoint in this function.
- LLVM_ATTRIBUTE_NOINLINE void __jit_debug_register_code() { }
-
- // We put information about the JITed function in this global, which the
- // debugger reads. Make sure to specify the version statically, because the
- // debugger checks the version before we can set it during runtime.
- struct jit_descriptor __jit_debug_descriptor = { 1, 0, 0, 0 };
-
-}
-
-namespace {
-
- /// JITDebugLock - Used to serialize all code registration events, since they
- /// modify global variables.
- sys::Mutex JITDebugLock;
-
-}
-
-JITDebugRegisterer::JITDebugRegisterer(TargetMachine &tm) : TM(tm), FnMap() { }
-
-JITDebugRegisterer::~JITDebugRegisterer() {
- // Free all ELF memory.
- for (RegisteredFunctionsMap::iterator I = FnMap.begin(), E = FnMap.end();
- I != E; ++I) {
- // Call the private method that doesn't update the map so our iterator
- // doesn't break.
- UnregisterFunctionInternal(I);
- }
- FnMap.clear();
-}
-
-std::string JITDebugRegisterer::MakeELF(const Function *F, DebugInfo &I) {
- // Stack allocate an empty module with an empty LLVMContext for the ELFWriter
- // API. We don't use the real module because then the ELFWriter would write
- // out unnecessary GlobalValues during finalization.
- LLVMContext Context;
- Module M("", Context);
-
- // Make a buffer for the ELF in memory.
- std::string Buffer;
- raw_string_ostream O(Buffer);
- ELFWriter EW(O, TM);
- EW.doInitialization(M);
-
- // Copy the binary into the .text section. This isn't necessary, but it's
- // useful to be able to disassemble the ELF by hand.
- ELFSection &Text = EW.getTextSection(const_cast<Function *>(F));
- Text.Addr = (uint64_t)I.FnStart;
- // TODO: We could eliminate this copy if we somehow used a pointer/size pair
- // instead of a vector.
- Text.getData().assign(I.FnStart, I.FnEnd);
-
- // Copy the exception handling call frame information into the .eh_frame
- // section. This allows GDB to get a good stack trace, particularly on
- // linux x86_64. Mark this as a PROGBITS section that needs to be loaded
- // into memory at runtime.
- ELFSection &EH = EW.getSection(".eh_frame", ELF::SHT_PROGBITS,
- ELF::SHF_ALLOC);
- // Pointers in the DWARF EH info are all relative to the EH frame start,
- // which is stored here.
- EH.Addr = (uint64_t)I.EhStart;
- // TODO: We could eliminate this copy if we somehow used a pointer/size pair
- // instead of a vector.
- EH.getData().assign(I.EhStart, I.EhEnd);
-
- // Add this single function to the symbol table, so the debugger prints the
- // name instead of '???'. We give the symbol default global visibility.
- ELFSym *FnSym = ELFSym::getGV(F,
- ELF::STB_GLOBAL,
- ELF::STT_FUNC,
- ELF::STV_DEFAULT);
- FnSym->SectionIdx = Text.SectionIdx;
- FnSym->Size = I.FnEnd - I.FnStart;
- FnSym->Value = 0; // Offset from start of section.
- EW.SymbolList.push_back(FnSym);
-
- EW.doFinalization(M);
- O.flush();
-
- // When trying to debug why GDB isn't getting the debug info right, it's
- // awfully helpful to write the object file to disk so that it can be
- // inspected with readelf and objdump.
- if (TM.Options.JITEmitDebugInfoToDisk) {
- std::string Filename;
- raw_string_ostream O2(Filename);
- O2 << "/tmp/llvm_function_" << I.FnStart << "_" << F->getName() << ".o";
- O2.flush();
- std::string Errors;
- raw_fd_ostream O3(Filename.c_str(), Errors);
- O3 << Buffer;
- O3.close();
- }
-
- return Buffer;
-}
-
-void JITDebugRegisterer::RegisterFunction(const Function *F, DebugInfo &I) {
- // TODO: Support non-ELF platforms.
- if (!TM.getELFWriterInfo())
- return;
-
- std::string Buffer = MakeELF(F, I);
-
- jit_code_entry *JITCodeEntry = new jit_code_entry();
- JITCodeEntry->symfile_addr = Buffer.c_str();
- JITCodeEntry->symfile_size = Buffer.size();
-
- // Add a mapping from F to the entry and buffer, so we can delete this
- // info later.
- FnMap[F] = std::make_pair(Buffer, JITCodeEntry);
-
- // Acquire the lock and do the registration.
- {
- MutexGuard locked(JITDebugLock);
- __jit_debug_descriptor.action_flag = JIT_REGISTER_FN;
-
- // Insert this entry at the head of the list.
- JITCodeEntry->prev_entry = NULL;
- jit_code_entry *NextEntry = __jit_debug_descriptor.first_entry;
- JITCodeEntry->next_entry = NextEntry;
- if (NextEntry != NULL) {
- NextEntry->prev_entry = JITCodeEntry;
- }
- __jit_debug_descriptor.first_entry = JITCodeEntry;
- __jit_debug_descriptor.relevant_entry = JITCodeEntry;
- __jit_debug_register_code();
- }
-}
-
-void JITDebugRegisterer::UnregisterFunctionInternal(
- RegisteredFunctionsMap::iterator I) {
- jit_code_entry *&JITCodeEntry = I->second.second;
-
- // Acquire the lock and do the unregistration.
- {
- MutexGuard locked(JITDebugLock);
- __jit_debug_descriptor.action_flag = JIT_UNREGISTER_FN;
-
- // Remove the jit_code_entry from the linked list.
- jit_code_entry *PrevEntry = JITCodeEntry->prev_entry;
- jit_code_entry *NextEntry = JITCodeEntry->next_entry;
- if (NextEntry) {
- NextEntry->prev_entry = PrevEntry;
- }
- if (PrevEntry) {
- PrevEntry->next_entry = NextEntry;
- } else {
- assert(__jit_debug_descriptor.first_entry == JITCodeEntry);
- __jit_debug_descriptor.first_entry = NextEntry;
- }
-
- // Tell GDB which entry we removed, and unregister the code.
- __jit_debug_descriptor.relevant_entry = JITCodeEntry;
- __jit_debug_register_code();
- }
-
- delete JITCodeEntry;
- JITCodeEntry = NULL;
-
- // Free the ELF file in memory.
- std::string &Buffer = I->second.first;
- Buffer.clear();
-}
-
-void JITDebugRegisterer::UnregisterFunction(const Function *F) {
- // TODO: Support non-ELF platforms.
- if (!TM.getELFWriterInfo())
- return;
-
- RegisteredFunctionsMap::iterator I = FnMap.find(F);
- if (I == FnMap.end()) return;
- UnregisterFunctionInternal(I);
- FnMap.erase(I);
-}
-
-} // end namespace llvm