LLVM 19.0.0git
OProfileJITEventListener.cpp
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1//===-- OProfileJITEventListener.cpp - Tell OProfile about JITted code ----===//
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 file defines a JITEventListener object that uses OProfileWrapper to tell
10// oprofile about JITted functions, including source line information.
11//
12//===----------------------------------------------------------------------===//
13
16#include "llvm/Config/config.h"
21#include "llvm/IR/DebugInfo.h"
22#include "llvm/IR/Function.h"
25#include "llvm/Support/Debug.h"
26#include "llvm/Support/Errno.h"
28#include <dirent.h>
29#include <fcntl.h>
30
31using namespace llvm;
32using namespace llvm::object;
33
34#define DEBUG_TYPE "oprofile-jit-event-listener"
35
36namespace {
37
38class OProfileJITEventListener : public JITEventListener {
39 std::unique_ptr<OProfileWrapper> Wrapper;
40
41 void initialize();
42 std::map<ObjectKey, OwningBinary<ObjectFile>> DebugObjects;
43
44public:
45 OProfileJITEventListener(std::unique_ptr<OProfileWrapper> LibraryWrapper)
46 : Wrapper(std::move(LibraryWrapper)) {
47 initialize();
48 }
49
50 ~OProfileJITEventListener();
51
52 void notifyObjectLoaded(ObjectKey Key, const ObjectFile &Obj,
53 const RuntimeDyld::LoadedObjectInfo &L) override;
54
55 void notifyFreeingObject(ObjectKey Key) override;
56};
57
58void OProfileJITEventListener::initialize() {
59 if (!Wrapper->op_open_agent()) {
60 const std::string err_str = sys::StrError();
61 LLVM_DEBUG(dbgs() << "Failed to connect to OProfile agent: " << err_str
62 << "\n");
63 } else {
64 LLVM_DEBUG(dbgs() << "Connected to OProfile agent.\n");
65 }
66}
67
68OProfileJITEventListener::~OProfileJITEventListener() {
69 if (Wrapper->isAgentAvailable()) {
70 if (Wrapper->op_close_agent() == -1) {
71 const std::string err_str = sys::StrError();
72 LLVM_DEBUG(dbgs() << "Failed to disconnect from OProfile agent: "
73 << err_str << "\n");
74 } else {
75 LLVM_DEBUG(dbgs() << "Disconnected from OProfile agent.\n");
76 }
77 }
78}
79
80void OProfileJITEventListener::notifyObjectLoaded(
81 ObjectKey Key, const ObjectFile &Obj,
83 if (!Wrapper->isAgentAvailable()) {
84 return;
85 }
86
87 OwningBinary<ObjectFile> DebugObjOwner = L.getObjectForDebug(Obj);
88 const ObjectFile &DebugObj = *DebugObjOwner.getBinary();
89 std::unique_ptr<DIContext> Context = DWARFContext::create(DebugObj);
90
91 // Use symbol info to iterate functions in the object.
92 for (const std::pair<SymbolRef, uint64_t> &P : computeSymbolSizes(DebugObj)) {
93 SymbolRef Sym = P.first;
94 if (!Sym.getType() || *Sym.getType() != SymbolRef::ST_Function)
95 continue;
96
97 Expected<StringRef> NameOrErr = Sym.getName();
98 if (!NameOrErr)
99 continue;
100 StringRef Name = *NameOrErr;
101 Expected<uint64_t> AddrOrErr = Sym.getAddress();
102 if (!AddrOrErr)
103 continue;
104 uint64_t Addr = *AddrOrErr;
105 uint64_t Size = P.second;
106
107 if (Wrapper->op_write_native_code(Name.data(), Addr, (void *)Addr, Size) ==
108 -1) {
109 LLVM_DEBUG(dbgs() << "Failed to tell OProfile about native function "
110 << Name << " at [" << (void *)Addr << "-"
111 << ((char *)Addr + Size) << "]\n");
112 continue;
113 }
114
115 DILineInfoTable Lines = Context->getLineInfoForAddressRange(Addr, Size);
116 size_t i = 0;
117 size_t num_entries = Lines.size();
118 struct debug_line_info *debug_line;
119 debug_line = (struct debug_line_info *)calloc(
120 num_entries, sizeof(struct debug_line_info));
121
122 for (auto& It : Lines) {
123 debug_line[i].vma = (unsigned long)It.first;
124 debug_line[i].lineno = It.second.Line;
125 debug_line[i].filename =
126 const_cast<char *>(Lines.front().second.FileName.c_str());
127 ++i;
128 }
129
130 if (Wrapper->op_write_debug_line_info((void *)Addr, num_entries,
131 debug_line) == -1) {
132 LLVM_DEBUG(dbgs() << "Failed to tell OProfiler about debug object at ["
133 << (void *)Addr << "-" << ((char *)Addr + Size)
134 << "]\n");
135 continue;
136 }
137 }
138
139 DebugObjects[Key] = std::move(DebugObjOwner);
140}
141
142void OProfileJITEventListener::notifyFreeingObject(ObjectKey Key) {
143 if (Wrapper->isAgentAvailable()) {
144
145 // If there was no agent registered when the original object was loaded then
146 // we won't have created a debug object for it, so bail out.
147 if (DebugObjects.find(Key) == DebugObjects.end())
148 return;
149
150 const ObjectFile &DebugObj = *DebugObjects[Key].getBinary();
151
152 // Use symbol info to iterate functions in the object.
153 for (symbol_iterator I = DebugObj.symbol_begin(),
154 E = DebugObj.symbol_end();
155 I != E; ++I) {
156 if (I->getType() && *I->getType() == SymbolRef::ST_Function) {
157 Expected<uint64_t> AddrOrErr = I->getAddress();
158 if (!AddrOrErr)
159 continue;
160 uint64_t Addr = *AddrOrErr;
161
162 if (Wrapper->op_unload_native_code(Addr) == -1) {
164 dbgs()
165 << "Failed to tell OProfile about unload of native function at "
166 << (void *)Addr << "\n");
167 continue;
168 }
169 }
170 }
171 }
172
173 DebugObjects.erase(Key);
174}
175
176} // anonymous namespace.
177
178namespace llvm {
180 return new OProfileJITEventListener(std::make_unique<OProfileWrapper>());
181}
182
183} // namespace llvm
184
186{
188}
amdgpu aa AMDGPU Address space based Alias Analysis Wrapper
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
#define LLVM_DEBUG(X)
Definition: Debug.h:101
uint64_t Addr
std::string Name
uint64_t Size
Symbol * Sym
Definition: ELF_riscv.cpp:479
#define I(x, y, z)
Definition: MD5.cpp:58
LLVMContext & Context
#define P(N)
static void initialize(TargetLibraryInfoImpl &TLI, const Triple &T, ArrayRef< StringLiteral > StandardNames)
Initialize the set of available library functions based on the specified target triple.
static std::unique_ptr< DWARFContext > create(const object::ObjectFile &Obj, ProcessDebugRelocations RelocAction=ProcessDebugRelocations::Process, const LoadedObjectInfo *L=nullptr, std::string DWPName="", std::function< void(Error)> RecoverableErrorHandler=WithColor::defaultErrorHandler, std::function< void(Error)> WarningHandler=WithColor::defaultWarningHandler, bool ThreadSafe=false)
Tagged union holding either a T or a Error.
Definition: Error.h:474
JITEventListener - Abstract interface for use by the JIT to notify clients about significant events d...
virtual void notifyFreeingObject(ObjectKey K)
notifyFreeingObject - Called just before the memory associated with a previously emitted object is re...
virtual void notifyObjectLoaded(ObjectKey K, const object::ObjectFile &Obj, const RuntimeDyld::LoadedObjectInfo &L)
notifyObjectLoaded - Called after an object has had its sections allocated and addresses assigned to ...
static JITEventListener * createOProfileJITEventListener()
Information about the loaded object.
Definition: RuntimeDyld.h:69
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.
Definition: SmallVector.h:1209
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
This class is the base class for all object file types.
Definition: ObjectFile.h:229
This is a value type class that represents a single symbol in the list of symbols in the object file.
Definition: ObjectFile.h:168
virtual basic_symbol_iterator symbol_begin() const =0
virtual basic_symbol_iterator symbol_end() const =0
LLVMJITEventListenerRef LLVMCreateOProfileJITEventListener(void)
struct LLVMOpaqueJITEventListener * LLVMJITEventListenerRef
Definition: Types.h:165
std::vector< std::pair< SymbolRef, uint64_t > > computeSymbolSizes(const ObjectFile &O)
Definition: SymbolSize.cpp:50
std::string StrError()
Returns a string representation of the errno value, using whatever thread-safe variant of strerror() ...
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:163
LLVMAttributeRef wrap(Attribute Attr)
Definition: Attributes.h:282