LLVM  13.0.0git
Config.h
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1 //===-Config.h - LLVM Link Time Optimizer Configuration ---------*- 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 // This file defines the lto::Config data structure, which allows clients to
10 // configure LTO.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LTO_CONFIG_H
15 #define LLVM_LTO_CONFIG_H
16 
17 #include "llvm/ADT/DenseSet.h"
18 #include "llvm/Config/llvm-config.h"
19 #include "llvm/IR/DiagnosticInfo.h"
20 #include "llvm/IR/GlobalValue.h"
21 #include "llvm/IR/LLVMContext.h"
24 #include "llvm/Support/CodeGen.h"
26 
27 #include <functional>
28 
29 namespace llvm {
30 
31 class Error;
32 class Module;
33 class ModuleSummaryIndex;
34 class raw_pwrite_stream;
35 
36 namespace lto {
37 
38 /// LTO configuration. A linker can configure LTO by setting fields in this data
39 /// structure and passing it to the lto::LTO constructor.
40 struct Config {
41  enum VisScheme {
43  ELF,
44  };
45  // Note: when adding fields here, consider whether they need to be added to
46  // computeCacheKey in LTO.cpp.
47  std::string CPU;
49  std::vector<std::string> MAttrs;
50  std::vector<std::string> PassPlugins;
51  /// For adding passes that run right before codegen.
57  unsigned OptLevel = 2;
58  bool DisableVerify = false;
59 
60  /// Use the new pass manager
61  bool UseNewPM = LLVM_ENABLE_NEW_PASS_MANAGER;
62 
63  /// Flag to indicate that the optimizer should not assume builtins are present
64  /// on the target.
65  bool Freestanding = false;
66 
67  /// Disable entirely the optimizer, including importing for ThinLTO
68  bool CodeGenOnly = false;
69 
70  /// Run PGO context sensitive IR instrumentation.
71  bool RunCSIRInstr = false;
72 
73  /// Asserts whether we can assume whole program visibility during the LTO
74  /// link.
76 
77  /// Always emit a Regular LTO object even when it is empty because no Regular
78  /// LTO modules were linked. This option is useful for some build system which
79  /// want to know a priori all possible output files.
81 
82  /// Allows non-imported definitions to get the potentially more constraining
83  /// visibility from the prevailing definition. FromPrevailing is the default
84  /// because it works for many binary formats. ELF can use the more optimized
85  /// 'ELF' scheme.
87 
88  /// If this field is set, the set of passes run in the middle-end optimizer
89  /// will be the one specified by the string. Only works with the new pass
90  /// manager as the old one doesn't have this ability.
91  std::string OptPipeline;
92 
93  // If this field is set, it has the same effect of specifying an AA pipeline
94  // identified by the string. Only works with the new pass manager, in
95  // conjunction OptPipeline.
96  std::string AAPipeline;
97 
98  /// Setting this field will replace target triples in input files with this
99  /// triple.
100  std::string OverrideTriple;
101 
102  /// Setting this field will replace unspecified target triples in input files
103  /// with this triple.
104  std::string DefaultTriple;
105 
106  /// Context Sensitive PGO profile path.
107  std::string CSIRProfile;
108 
109  /// Sample PGO profile path.
110  std::string SampleProfile;
111 
112  /// Name remapping file for profile data.
113  std::string ProfileRemapping;
114 
115  /// The directory to store .dwo files.
116  std::string DwoDir;
117 
118  /// The name for the split debug info file used for the DW_AT_[GNU_]dwo_name
119  /// attribute in the skeleton CU. This should generally only be used when
120  /// running an individual backend directly via thinBackend(), as otherwise
121  /// all objects would use the same .dwo file. Not used as output path.
122  std::string SplitDwarfFile;
123 
124  /// The path to write a .dwo file to. This should generally only be used when
125  /// running an individual backend directly via thinBackend(), as otherwise
126  /// all .dwo files will be written to the same path. Not used in skeleton CU.
127  std::string SplitDwarfOutput;
128 
129  /// Optimization remarks file path.
130  std::string RemarksFilename;
131 
132  /// Optimization remarks pass filter.
133  std::string RemarksPasses;
134 
135  /// Whether to emit optimization remarks with hotness informations.
136  bool RemarksWithHotness = false;
137 
138  /// The minimum hotness value a diagnostic needs in order to be included in
139  /// optimization diagnostics.
140  ///
141  /// The threshold is an Optional value, which maps to one of the 3 states:
142  /// 1. 0 => threshold disabled. All emarks will be printed.
143  /// 2. positive int => manual threshold by user. Remarks with hotness exceed
144  /// threshold will be printed.
145  /// 3. None => 'auto' threshold by user. The actual value is not
146  /// available at command line, but will be synced with
147  /// hotness threhold from profile summary during
148  /// compilation.
149  ///
150  /// If threshold option is not specified, it is disabled by default.
152 
153  /// The format used for serializing remarks (default: YAML).
154  std::string RemarksFormat;
155 
156  /// Whether to emit the pass manager debuggging informations.
157  bool DebugPassManager = false;
158 
159  /// Statistics output file path.
160  std::string StatsFile;
161 
162  /// Specific thinLTO modules to compile.
163  std::vector<std::string> ThinLTOModulesToCompile;
164 
165  /// Time trace enabled.
166  bool TimeTraceEnabled = false;
167 
168  /// Time trace granularity.
169  unsigned TimeTraceGranularity = 500;
170 
173 
174  /// Add FSAFDO discriminators.
175  bool AddFSDiscriminator = false;
176 
177  /// If this field is set, LTO will write input file paths and symbol
178  /// resolutions here in llvm-lto2 command line flag format. This can be
179  /// used for testing and for running the LTO pipeline outside of the linker
180  /// with llvm-lto2.
181  std::unique_ptr<raw_ostream> ResolutionFile;
182 
183  /// Tunable parameters for passes in the default pipelines.
185 
186  /// The following callbacks deal with tasks, which normally represent the
187  /// entire optimization and code generation pipeline for what will become a
188  /// single native object file. Each task has a unique identifier between 0 and
189  /// getMaxTasks()-1, which is supplied to the callback via the Task parameter.
190  /// A task represents the entire pipeline for ThinLTO and regular
191  /// (non-parallel) LTO, but a parallel code generation task will be split into
192  /// N tasks before code generation, where N is the parallelism level.
193  ///
194  /// LTO may decide to stop processing a task at any time, for example if the
195  /// module is empty or if a module hook (see below) returns false. For this
196  /// reason, the client should not expect to receive exactly getMaxTasks()
197  /// native object files.
198 
199  /// A module hook may be used by a linker to perform actions during the LTO
200  /// pipeline. For example, a linker may use this function to implement
201  /// -save-temps. If this function returns false, any further processing for
202  /// that task is aborted.
203  ///
204  /// Module hooks must be thread safe with respect to the linker's internal
205  /// data structures. A module hook will never be called concurrently from
206  /// multiple threads with the same task ID, or the same module.
207  ///
208  /// Note that in out-of-process backend scenarios, none of the hooks will be
209  /// called for ThinLTO tasks.
210  using ModuleHookFn = std::function<bool(unsigned Task, const Module &)>;
211 
212  /// This module hook is called after linking (regular LTO) or loading
213  /// (ThinLTO) the module, before modifying it.
215 
216  /// This hook is called after promoting any internal functions
217  /// (ThinLTO-specific).
219 
220  /// This hook is called after internalizing the module.
222 
223  /// This hook is called after importing from other modules (ThinLTO-specific).
225 
226  /// This module hook is called after optimization is complete.
228 
229  /// This module hook is called before code generation. It is similar to the
230  /// PostOptModuleHook, but for parallel code generation it is called after
231  /// splitting the module.
233 
234  /// A combined index hook is called after all per-module indexes have been
235  /// combined (ThinLTO-specific). It can be used to implement -save-temps for
236  /// the combined index.
237  ///
238  /// If this function returns false, any further processing for ThinLTO tasks
239  /// is aborted.
240  ///
241  /// It is called regardless of whether the backend is in-process, although it
242  /// is not called from individual backend processes.
243  using CombinedIndexHookFn = std::function<bool(
244  const ModuleSummaryIndex &Index,
245  const DenseSet<GlobalValue::GUID> &GUIDPreservedSymbols)>;
247 
248  /// This is a convenience function that configures this Config object to write
249  /// temporary files named after the given OutputFileName for each of the LTO
250  /// phases to disk. A client can use this function to implement -save-temps.
251  ///
252  /// FIXME: Temporary files derived from ThinLTO backends are currently named
253  /// after the input file name, rather than the output file name, when
254  /// UseInputModulePath is set to true.
255  ///
256  /// Specifically, it (1) sets each of the above module hooks and the combined
257  /// index hook to a function that calls the hook function (if any) that was
258  /// present in the appropriate field when the addSaveTemps function was
259  /// called, and writes the module to a bitcode file with a name prefixed by
260  /// the given output file name, and (2) creates a resolution file whose name
261  /// is prefixed by the given output file name and sets ResolutionFile to its
262  /// file handle.
263  Error addSaveTemps(std::string OutputFileName,
264  bool UseInputModulePath = false);
265 };
266 
270  : Fn(DiagHandlerFn) {}
271  bool handleDiagnostics(const DiagnosticInfo &DI) override {
272  (*Fn)(DI);
273  return true;
274  }
275 };
276 /// A derived class of LLVMContext that initializes itself according to a given
277 /// Config object. The purpose of this class is to tie ownership of the
278 /// diagnostic handler to the context, as opposed to the Config object (which
279 /// may be ephemeral).
280 // FIXME: This should not be required as diagnostic handler is not callback.
282 
284  setDiscardValueNames(C.ShouldDiscardValueNames);
287  std::make_unique<LTOLLVMDiagnosticHandler>(&DiagHandler), true);
288  }
290 };
291 
292 }
293 }
294 
295 #endif
llvm::LLVMContext::enableDebugTypeODRUniquing
void enableDebugTypeODRUniquing()
Definition: LLVMContext.cpp:322
llvm
Definition: AllocatorList.h:23
PassBuilder.h
llvm::lltok::Error
@ Error
Definition: LLToken.h:21
llvm::CGFT_ObjectFile
@ CGFT_ObjectFile
Definition: CodeGen.h:65
llvm::TargetOptions
Definition: TargetOptions.h:113
llvm::lto::Config::DisableVerify
bool DisableVerify
Definition: Config.h:58
llvm::lto::Config::CGOptLevel
CodeGenOpt::Level CGOptLevel
Definition: Config.h:55
llvm::lto::Config::DiagHandler
DiagnosticHandlerFunction DiagHandler
Definition: Config.h:172
llvm::lto::Config::TimeTraceGranularity
unsigned TimeTraceGranularity
Time trace granularity.
Definition: Config.h:169
llvm::lto::Config::RemarksFormat
std::string RemarksFormat
The format used for serializing remarks (default: YAML).
Definition: Config.h:154
llvm::lto::Config::CodeModel
Optional< CodeModel::Model > CodeModel
Definition: Config.h:54
llvm::lto::Config::RemarksWithHotness
bool RemarksWithHotness
Whether to emit optimization remarks with hotness informations.
Definition: Config.h:136
llvm::PipelineTuningOptions
Tunable parameters for passes in the default pipelines.
Definition: PassBuilder.h:86
llvm::lto::Config::ThinLTOModulesToCompile
std::vector< std::string > ThinLTOModulesToCompile
Specific thinLTO modules to compile.
Definition: Config.h:163
llvm::DiagnosticHandler
This is the base class for diagnostic handling in LLVM.
Definition: DiagnosticHandler.h:24
llvm::lto::Config
LTO configuration.
Definition: Config.h:40
llvm::Optional< Reloc::Model >
llvm::lto::Config::Freestanding
bool Freestanding
Flag to indicate that the optimizer should not assume builtins are present on the target.
Definition: Config.h:65
llvm::lto::LTOLLVMDiagnosticHandler::LTOLLVMDiagnosticHandler
LTOLLVMDiagnosticHandler(DiagnosticHandlerFunction *DiagHandlerFn)
Definition: Config.h:269
llvm::lto::Config::ShouldDiscardValueNames
bool ShouldDiscardValueNames
Definition: Config.h:171
llvm::lto::Config::PostImportModuleHook
ModuleHookFn PostImportModuleHook
This hook is called after importing from other modules (ThinLTO-specific).
Definition: Config.h:224
llvm::lto::Config::CodeGenOnly
bool CodeGenOnly
Disable entirely the optimizer, including importing for ThinLTO.
Definition: Config.h:68
LegacyPassManager.h
llvm::lto::Config::CombinedIndexHook
CombinedIndexHookFn CombinedIndexHook
Definition: Config.h:246
llvm::lto::Config::VisScheme
VisScheme
Definition: Config.h:41
llvm::lto::Config::FromPrevailing
@ FromPrevailing
Definition: Config.h:42
llvm::lto::Config::SplitDwarfFile
std::string SplitDwarfFile
The name for the split debug info file used for the DW_AT_[GNU_]dwo_name attribute in the skeleton CU...
Definition: Config.h:122
llvm::lto::Config::RunCSIRInstr
bool RunCSIRInstr
Run PGO context sensitive IR instrumentation.
Definition: Config.h:71
GlobalValue.h
llvm::lto::Config::PostPromoteModuleHook
ModuleHookFn PostPromoteModuleHook
This hook is called after promoting any internal functions (ThinLTO-specific).
Definition: Config.h:218
llvm::lto::Config::SampleProfile
std::string SampleProfile
Sample PGO profile path.
Definition: Config.h:110
C
(vector float) vec_cmpeq(*A, *B) C
Definition: README_ALTIVEC.txt:86
llvm::lto::Config::Options
TargetOptions Options
Definition: Config.h:48
llvm::lto::LTOLLVMDiagnosticHandler::Fn
DiagnosticHandlerFunction * Fn
Definition: Config.h:268
llvm::lto::Config::PreCodeGenPassesHook
std::function< void(legacy::PassManager &)> PreCodeGenPassesHook
For adding passes that run right before codegen.
Definition: Config.h:52
llvm::lto::Config::VisibilityScheme
VisScheme VisibilityScheme
Allows non-imported definitions to get the potentially more constraining visibility from the prevaili...
Definition: Config.h:86
llvm::lto::Config::ELF
@ ELF
Definition: Config.h:43
DenseSet.h
llvm::DiagnosticHandlerFunction
std::function< void(const DiagnosticInfo &)> DiagnosticHandlerFunction
Definition: DiagnosticInfo.h:127
llvm::lto::Config::ResolutionFile
std::unique_ptr< raw_ostream > ResolutionFile
If this field is set, LTO will write input file paths and symbol resolutions here in llvm-lto2 comman...
Definition: Config.h:181
llvm::lto::LTOLLVMDiagnosticHandler
Definition: Config.h:267
llvm::lto::LTOLLVMContext::LTOLLVMContext
LTOLLVMContext(const Config &C)
Definition: Config.h:283
llvm::DiagnosticInfo
This is the base abstract class for diagnostic reporting in the backend.
Definition: DiagnosticInfo.h:101
llvm::lto::Config::ModuleHookFn
std::function< bool(unsigned Task, const Module &)> ModuleHookFn
The following callbacks deal with tasks, which normally represent the entire optimization and code ge...
Definition: Config.h:210
llvm::lto::Config::DebugPassManager
bool DebugPassManager
Whether to emit the pass manager debuggging informations.
Definition: Config.h:157
llvm::LLVMContext::setDiagnosticHandler
void setDiagnosticHandler(std::unique_ptr< DiagnosticHandler > &&DH, bool RespectFilters=false)
setDiagnosticHandler - This method sets unique_ptr to object of DiagnosticHandler to provide custom d...
Definition: LLVMContext.cpp:122
llvm::None
const NoneType None
Definition: None.h:23
llvm::lto::Config::StatsFile
std::string StatsFile
Statistics output file path.
Definition: Config.h:160
llvm::lto::Config::PostInternalizeModuleHook
ModuleHookFn PostInternalizeModuleHook
This hook is called after internalizing the module.
Definition: Config.h:221
llvm::lto::Config::OverrideTriple
std::string OverrideTriple
Setting this field will replace target triples in input files with this triple.
Definition: Config.h:100
llvm::lto::Config::PreCodeGenModuleHook
ModuleHookFn PreCodeGenModuleHook
This module hook is called before code generation.
Definition: Config.h:232
llvm::lto::Config::OptLevel
unsigned OptLevel
Definition: Config.h:57
llvm::DenseSet< GlobalValue::GUID >
llvm::lto::Config::RemarksFilename
std::string RemarksFilename
Optimization remarks file path.
Definition: Config.h:130
llvm::lto::Config::DefaultTriple
std::string DefaultTriple
Setting this field will replace unspecified target triples in input files with this triple.
Definition: Config.h:104
llvm::lto::LTOLLVMDiagnosticHandler::handleDiagnostics
bool handleDiagnostics(const DiagnosticInfo &DI) override
Override handleDiagnostics to provide custom implementation.
Definition: Config.h:271
llvm::CodeGenOpt::Default
@ Default
Definition: CodeGen.h:55
Index
uint32_t Index
Definition: ELFObjHandler.cpp:84
llvm::lto::Config::DwoDir
std::string DwoDir
The directory to store .dwo files.
Definition: Config.h:116
llvm::lto::Config::AddFSDiscriminator
bool AddFSDiscriminator
Add FSAFDO discriminators.
Definition: Config.h:175
llvm::LLVMContext
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:68
llvm::lto::LTOLLVMContext
A derived class of LLVMContext that initializes itself according to a given Config object.
Definition: Config.h:281
llvm::lto::Config::addSaveTemps
Error addSaveTemps(std::string OutputFileName, bool UseInputModulePath=false)
This is a convenience function that configures this Config object to write temporary files named afte...
Definition: LTOBackend.cpp:83
llvm::lto::Config::SplitDwarfOutput
std::string SplitDwarfOutput
The path to write a .dwo file to.
Definition: Config.h:127
function
print Print MemDeps of function
Definition: MemDepPrinter.cpp:83
llvm::lto::Config::MAttrs
std::vector< std::string > MAttrs
Definition: Config.h:49
llvm::Module
A Module instance is used to store all the information related to an LLVM module.
Definition: Module.h:67
llvm::lto::Config::ProfileRemapping
std::string ProfileRemapping
Name remapping file for profile data.
Definition: Config.h:113
TargetOptions.h
llvm::lto::Config::RelocModel
Optional< Reloc::Model > RelocModel
Definition: Config.h:53
llvm::lto::Config::PostOptModuleHook
ModuleHookFn PostOptModuleHook
This module hook is called after optimization is complete.
Definition: Config.h:227
llvm::lto::Config::RemarksHotnessThreshold
llvm::Optional< uint64_t > RemarksHotnessThreshold
The minimum hotness value a diagnostic needs in order to be included in optimization diagnostics.
Definition: Config.h:151
llvm::lto::Config::HasWholeProgramVisibility
bool HasWholeProgramVisibility
Asserts whether we can assume whole program visibility during the LTO link.
Definition: Config.h:75
llvm::Reloc::PIC_
@ PIC_
Definition: CodeGen.h:22
llvm::CodeGenFileType
CodeGenFileType
These enums are meant to be passed into addPassesToEmitFile to indicate what type of file to emit,...
Definition: CodeGen.h:63
llvm::lto::Config::TimeTraceEnabled
bool TimeTraceEnabled
Time trace enabled.
Definition: Config.h:166
Module
Machine Check Debug Module
Definition: MachineCheckDebugify.cpp:122
llvm::lto::Config::AlwaysEmitRegularLTOObj
bool AlwaysEmitRegularLTOObj
Always emit a Regular LTO object even when it is empty because no Regular LTO modules were linked.
Definition: Config.h:80
llvm::lto::Config::OptPipeline
std::string OptPipeline
If this field is set, the set of passes run in the middle-end optimizer will be the one specified by ...
Definition: Config.h:91
llvm::CodeGenOpt::Level
Level
Definition: CodeGen.h:52
llvm::Error
Lightweight error class with error context and mandatory checking.
Definition: Error.h:157
llvm::legacy::PassManager
PassManager manages ModulePassManagers.
Definition: LegacyPassManager.h:52
llvm::lto::LTOLLVMContext::DiagHandler
DiagnosticHandlerFunction DiagHandler
Definition: Config.h:289
DiagnosticInfo.h
llvm::lto::Config::AAPipeline
std::string AAPipeline
Definition: Config.h:96
llvm::LLVMContext::setDiscardValueNames
void setDiscardValueNames(bool Discard)
Set the Context runtime configuration to discard all value name (but GlobalValue).
Definition: LLVMContext.cpp:331
llvm::lto::Config::PreOptModuleHook
ModuleHookFn PreOptModuleHook
This module hook is called after linking (regular LTO) or loading (ThinLTO) the module,...
Definition: Config.h:214
llvm::lto::Config::PTO
PipelineTuningOptions PTO
Tunable parameters for passes in the default pipelines.
Definition: Config.h:184
llvm::lto::Config::CSIRProfile
std::string CSIRProfile
Context Sensitive PGO profile path.
Definition: Config.h:107
llvm::lto::Config::CombinedIndexHookFn
std::function< bool(const ModuleSummaryIndex &Index, const DenseSet< GlobalValue::GUID > &GUIDPreservedSymbols)> CombinedIndexHookFn
A combined index hook is called after all per-module indexes have been combined (ThinLTO-specific).
Definition: Config.h:245
CodeGen.h
llvm::lto::Config::CGFileType
CodeGenFileType CGFileType
Definition: Config.h:56
llvm::lto::Config::UseNewPM
bool UseNewPM
Use the new pass manager.
Definition: Config.h:61
llvm::ModuleSummaryIndex
Class to hold module path string table and global value map, and encapsulate methods for operating on...
Definition: ModuleSummaryIndex.h:1026
llvm::lto::Config::PassPlugins
std::vector< std::string > PassPlugins
Definition: Config.h:50
llvm::lto::Config::CPU
std::string CPU
Definition: Config.h:47
LLVMContext.h
llvm::lto::Config::RemarksPasses
std::string RemarksPasses
Optimization remarks pass filter.
Definition: Config.h:133