Instrumentation.h revision 321369 
1//===- Transforms/Instrumentation.h - Instrumentation passes ----*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines constructor functions for instrumentation passes.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_TRANSFORMS_INSTRUMENTATION_H
15#define LLVM_TRANSFORMS_INSTRUMENTATION_H
16
17#include "llvm/ADT/StringRef.h"
18#include "llvm/IR/BasicBlock.h"
19#include <cassert>
20#include <cstdint>
21#include <limits>
22#include <string>
23#include <vector>
24
25#if defined(__GNUC__) && defined(__linux__) && !defined(ANDROID)
26inline void *getDFSanArgTLSPtrForJIT() {
27  extern __thread __attribute__((tls_model("initial-exec")))
28    void *__dfsan_arg_tls;
29  return (void *)&__dfsan_arg_tls;
30}
31
32inline void *getDFSanRetValTLSPtrForJIT() {
33  extern __thread __attribute__((tls_model("initial-exec")))
34    void *__dfsan_retval_tls;
35  return (void *)&__dfsan_retval_tls;
36}
37#endif
38
39namespace llvm {
40
41class FunctionPass;
42class ModulePass;
43
44/// Instrumentation passes often insert conditional checks into entry blocks.
45/// Call this function before splitting the entry block to move instructions
46/// that must remain in the entry block up before the split point. Static
47/// allocas and llvm.localescape calls, for example, must remain in the entry
48/// block.
49BasicBlock::iterator PrepareToSplitEntryBlock(BasicBlock &BB,
50                                              BasicBlock::iterator IP);
51
52// Insert GCOV profiling instrumentation
53struct GCOVOptions {
54  static GCOVOptions getDefault();
55
56  // Specify whether to emit .gcno files.
57  bool EmitNotes;
58
59  // Specify whether to modify the program to emit .gcda files when run.
60  bool EmitData;
61
62  // A four-byte version string. The meaning of a version string is described in
63  // gcc's gcov-io.h
64  char Version[4];
65
66  // Emit a "cfg checksum" that follows the "line number checksum" of a
67  // function. This affects both .gcno and .gcda files.
68  bool UseCfgChecksum;
69
70  // Add the 'noredzone' attribute to added runtime library calls.
71  bool NoRedZone;
72
73  // Emit the name of the function in the .gcda files. This is redundant, as
74  // the function identifier can be used to find the name from the .gcno file.
75  bool FunctionNamesInData;
76
77  // Emit the exit block immediately after the start block, rather than after
78  // all of the function body's blocks.
79  bool ExitBlockBeforeBody;
80};
81
82ModulePass *createGCOVProfilerPass(const GCOVOptions &Options =
83                                   GCOVOptions::getDefault());
84
85// PGO Instrumention
86ModulePass *createPGOInstrumentationGenLegacyPass();
87ModulePass *
88createPGOInstrumentationUseLegacyPass(StringRef Filename = StringRef(""));
89ModulePass *createPGOIndirectCallPromotionLegacyPass(bool InLTO = false,
90                                                     bool SamplePGO = false);
91FunctionPass *createPGOMemOPSizeOptLegacyPass();
92
93// Helper function to check if it is legal to promote indirect call \p Inst
94// to a direct call of function \p F. Stores the reason in \p Reason.
95bool isLegalToPromote(Instruction *Inst, Function *F, const char **Reason);
96
97// Helper function that transforms Inst (either an indirect-call instruction, or
98// an invoke instruction , to a conditional call to F. This is like:
99//     if (Inst.CalledValue == F)
100//        F(...);
101//     else
102//        Inst(...);
103//     end
104// TotalCount is the profile count value that the instruction executes.
105// Count is the profile count value that F is the target function.
106// These two values are used to update the branch weight.
107// If \p AttachProfToDirectCall is true, a prof metadata is attached to the
108// new direct call to contain \p Count.
109// Returns the promoted direct call instruction.
110Instruction *promoteIndirectCall(Instruction *Inst, Function *F, uint64_t Count,
111                                 uint64_t TotalCount,
112                                 bool AttachProfToDirectCall);
113
114/// Options for the frontend instrumentation based profiling pass.
115struct InstrProfOptions {
116  // Add the 'noredzone' attribute to added runtime library calls.
117  bool NoRedZone = false;
118
119  // Do counter register promotion
120  bool DoCounterPromotion = false;
121
122  // Name of the profile file to use as output
123  std::string InstrProfileOutput;
124
125  InstrProfOptions() = default;
126};
127
128/// Insert frontend instrumentation based profiling.
129ModulePass *createInstrProfilingLegacyPass(
130    const InstrProfOptions &Options = InstrProfOptions());
131
132// Insert AddressSanitizer (address sanity checking) instrumentation
133FunctionPass *createAddressSanitizerFunctionPass(bool CompileKernel = false,
134                                                 bool Recover = false,
135                                                 bool UseAfterScope = false);
136ModulePass *createAddressSanitizerModulePass(bool CompileKernel = false,
137                                             bool Recover = false,
138                                             bool UseGlobalsGC = true);
139
140// Insert MemorySanitizer instrumentation (detection of uninitialized reads)
141FunctionPass *createMemorySanitizerPass(int TrackOrigins = 0,
142                                        bool Recover = false);
143
144// Insert ThreadSanitizer (race detection) instrumentation
145FunctionPass *createThreadSanitizerPass();
146
147// Insert DataFlowSanitizer (dynamic data flow analysis) instrumentation
148ModulePass *createDataFlowSanitizerPass(
149    const std::vector<std::string> &ABIListFiles = std::vector<std::string>(),
150    void *(*getArgTLS)() = nullptr, void *(*getRetValTLS)() = nullptr);
151
152// Options for EfficiencySanitizer sub-tools.
153struct EfficiencySanitizerOptions {
154  enum Type {
155    ESAN_None = 0,
156    ESAN_CacheFrag,
157    ESAN_WorkingSet,
158  } ToolType = ESAN_None;
159
160  EfficiencySanitizerOptions() = default;
161};
162
163// Insert EfficiencySanitizer instrumentation.
164ModulePass *createEfficiencySanitizerPass(
165    const EfficiencySanitizerOptions &Options = EfficiencySanitizerOptions());
166
167// Options for sanitizer coverage instrumentation.
168struct SanitizerCoverageOptions {
169  enum Type {
170    SCK_None = 0,
171    SCK_Function,
172    SCK_BB,
173    SCK_Edge
174  } CoverageType = SCK_None;
175  bool IndirectCalls = false;
176  bool TraceBB = false;
177  bool TraceCmp = false;
178  bool TraceDiv = false;
179  bool TraceGep = false;
180  bool Use8bitCounters = false;
181  bool TracePC = false;
182  bool TracePCGuard = false;
183  bool Inline8bitCounters = false;
184  bool NoPrune = false;
185
186  SanitizerCoverageOptions() = default;
187};
188
189// Insert SanitizerCoverage instrumentation.
190ModulePass *createSanitizerCoverageModulePass(
191    const SanitizerCoverageOptions &Options = SanitizerCoverageOptions());
192
193#if defined(__GNUC__) && defined(__linux__) && !defined(ANDROID)
194inline ModulePass *createDataFlowSanitizerPassForJIT(
195    const std::vector<std::string> &ABIListFiles = std::vector<std::string>()) {
196  return createDataFlowSanitizerPass(ABIListFiles, getDFSanArgTLSPtrForJIT,
197                                     getDFSanRetValTLSPtrForJIT);
198}
199#endif
200
201// BoundsChecking - This pass instruments the code to perform run-time bounds
202// checking on loads, stores, and other memory intrinsics.
203FunctionPass *createBoundsCheckingPass();
204
205/// \brief Calculate what to divide by to scale counts.
206///
207/// Given the maximum count, calculate a divisor that will scale all the
208/// weights to strictly less than std::numeric_limits<uint32_t>::max().
209static inline uint64_t calculateCountScale(uint64_t MaxCount) {
210  return MaxCount < std::numeric_limits<uint32_t>::max()
211             ? 1
212             : MaxCount / std::numeric_limits<uint32_t>::max() + 1;
213}
214
215/// \brief Scale an individual branch count.
216///
217/// Scale a 64-bit weight down to 32-bits using \c Scale.
218///
219static inline uint32_t scaleBranchCount(uint64_t Count, uint64_t Scale) {
220  uint64_t Scaled = Count / Scale;
221  assert(Scaled <= std::numeric_limits<uint32_t>::max() && "overflow 32-bits");
222  return Scaled;
223}
224
225} // end namespace llvm
226
227#endif // LLVM_TRANSFORMS_INSTRUMENTATION_H
228