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//===-- OProfileJITEventListener.cpp - Tell OProfile about JITted code ----===//
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// The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//===----------------------------------------------------------------------===//
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// This file defines a JITEventListener object that calls into OProfile to tell
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// it about JITted functions. For now, we only record function names and sizes,
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// but eventually we'll also record line number information.
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// See http://oprofile.sourceforge.net/doc/devel/jit-interface.html for the
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// definition of the interface we're using.
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//===----------------------------------------------------------------------===//
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#define DEBUG_TYPE "oprofile-jit-event-listener"
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#include "llvm/Function.h"
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#include "llvm/Metadata.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/Analysis/DebugInfo.h"
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#include "llvm/CodeGen/MachineFunction.h"
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#include "llvm/ExecutionEngine/JITEventListener.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/ValueHandle.h"
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#include "llvm/Support/raw_ostream.h"
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#include "llvm/System/Errno.h"
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#include "llvm/Config/config.h"
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class OProfileJITEventListener : public JITEventListener {
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OProfileJITEventListener();
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~OProfileJITEventListener();
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virtual void NotifyFunctionEmitted(const Function &F,
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void *FnStart, size_t FnSize,
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const EmittedFunctionDetails &Details);
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virtual void NotifyFreeingMachineCode(void *OldPtr);
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OProfileJITEventListener::OProfileJITEventListener()
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: Agent(op_open_agent()) {
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const std::string err_str = sys::StrError();
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DEBUG(dbgs() << "Failed to connect to OProfile agent: " << err_str << "\n");
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DEBUG(dbgs() << "Connected to OProfile agent.\n");
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OProfileJITEventListener::~OProfileJITEventListener() {
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if (op_close_agent(Agent) == -1) {
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const std::string err_str = sys::StrError();
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DEBUG(dbgs() << "Failed to disconnect from OProfile agent: "
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DEBUG(dbgs() << "Disconnected from OProfile agent.\n");
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// Holds the filename of each Scope, so that we can pass a null-terminated
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// string into oprofile. Use an AssertingVH rather than a ValueMap because we
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// shouldn't be modifying any MDNodes while this map is alive.
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DenseMap<AssertingVH<MDNode>, std::string> Filenames;
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const char *getFilename(MDNode *Scope) {
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std::string &Filename = Filenames[Scope];
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if (Filename.empty()) {
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Filename = DIScope(Scope).getFilename();
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return Filename.c_str();
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static debug_line_info LineStartToOProfileFormat(
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const MachineFunction &MF, FilenameCache &Filenames,
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uintptr_t Address, DebugLoc Loc) {
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debug_line_info Result;
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Result.lineno = Loc.getLine();
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Result.filename = Filenames.getFilename(
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Loc.getScope(MF.getFunction()->getContext()));
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DEBUG(dbgs() << "Mapping " << reinterpret_cast<void*>(Result.vma) << " to "
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<< Result.filename << ":" << Result.lineno << "\n");
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// Adds the just-emitted function to the symbol table.
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void OProfileJITEventListener::NotifyFunctionEmitted(
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const Function &F, void *FnStart, size_t FnSize,
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const EmittedFunctionDetails &Details) {
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assert(F.hasName() && FnStart != 0 && "Bad symbol to add");
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if (op_write_native_code(Agent, F.getName().data(),
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reinterpret_cast<uint64_t>(FnStart),
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FnStart, FnSize) == -1) {
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DEBUG(dbgs() << "Failed to tell OProfile about native function "
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<< F.getName() << " at ["
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<< FnStart << "-" << ((char*)FnStart + FnSize) << "]\n");
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if (!Details.LineStarts.empty()) {
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// Now we convert the line number information from the address/DebugLoc
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// format in Details to the address/filename/lineno format that OProfile
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// expects. Note that OProfile 0.9.4 has a bug that causes it to ignore
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// line numbers for addresses above 4G.
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FilenameCache Filenames;
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std::vector<debug_line_info> LineInfo;
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LineInfo.reserve(1 + Details.LineStarts.size());
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DebugLoc FirstLoc = Details.LineStarts[0].Loc;
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assert(!FirstLoc.isUnknown()
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&& "LineStarts should not contain unknown DebugLocs");
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MDNode *FirstLocScope = FirstLoc.getScope(F.getContext());
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DISubprogram FunctionDI = getDISubprogram(FirstLocScope);
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if (FunctionDI.Verify()) {
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// If we have debug info for the function itself, use that as the line
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// number of the first several instructions. Otherwise, after filling
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// LineInfo, we'll adjust the address of the first line number to point at
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// the start of the function.
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debug_line_info line_info;
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line_info.vma = reinterpret_cast<uintptr_t>(FnStart);
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line_info.lineno = FunctionDI.getLineNumber();
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line_info.filename = Filenames.getFilename(FirstLocScope);
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LineInfo.push_back(line_info);
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for (std::vector<EmittedFunctionDetails::LineStart>::const_iterator
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I = Details.LineStarts.begin(), E = Details.LineStarts.end();
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LineInfo.push_back(LineStartToOProfileFormat(
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*Details.MF, Filenames, I->Address, I->Loc));
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// In case the function didn't have line info of its own, adjust the first
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// line info's address to include the start of the function.
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LineInfo[0].vma = reinterpret_cast<uintptr_t>(FnStart);
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if (op_write_debug_line_info(Agent, FnStart,
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LineInfo.size(), &*LineInfo.begin()) == -1) {
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<< "Failed to tell OProfile about line numbers for native function "
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<< F.getName() << " at ["
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<< FnStart << "-" << ((char*)FnStart + FnSize) << "]\n");
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// Removes the being-deleted function from the symbol table.
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void OProfileJITEventListener::NotifyFreeingMachineCode(void *FnStart) {
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assert(FnStart && "Invalid function pointer");
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if (op_unload_native_code(Agent, reinterpret_cast<uint64_t>(FnStart)) == -1) {
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<< "Failed to tell OProfile about unload of native function at "
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} // anonymous namespace.
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JITEventListener *createOProfileJITEventListener() {
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return new OProfileJITEventListener;
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#else // USE_OPROFILE
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// By defining this to return NULL, we can let clients call it unconditionally,
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// even if they haven't configured with the OProfile libraries.
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JITEventListener *createOProfileJITEventListener() {
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#endif // USE_OPROFILE