[CGData][ThinLTO][NFC] Prep for two-codegen rounds #90934
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@llvm/pr-subscribers-lto @llvm/pr-subscribers-clang-codegen Author: Kyungwoo Lee (kyulee-com) ChangesThis is NFC for #90933.
Depends on #90304. Full diff: https://github.com/llvm/llvm-project/pull/90934.diff 4 Files Affected:
diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index 7fa69420298160..a1909d45b4d944 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -1286,10 +1286,10 @@ static void runThinLTOBackend(
Conf.CGFileType = getCodeGenFileType(Action);
break;
}
- if (Error E =
- thinBackend(Conf, -1, AddStream, *M, *CombinedIndex, ImportList,
- ModuleToDefinedGVSummaries[M->getModuleIdentifier()],
- /* ModuleMap */ nullptr, CGOpts.CmdArgs)) {
+ if (Error E = thinBackend(
+ Conf, -1, AddStream, *M, *CombinedIndex, ImportList,
+ ModuleToDefinedGVSummaries[M->getModuleIdentifier()],
+ /* ModuleMap */ nullptr, Conf.CodeGenOnly, CGOpts.CmdArgs)) {
handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
errs() << "Error running ThinLTO backend: " << EIB.message() << '\n';
});
diff --git a/llvm/include/llvm/LTO/LTOBackend.h b/llvm/include/llvm/LTO/LTOBackend.h
index de89f4bb10dff2..8516398510d4b8 100644
--- a/llvm/include/llvm/LTO/LTOBackend.h
+++ b/llvm/include/llvm/LTO/LTOBackend.h
@@ -56,6 +56,7 @@ Error thinBackend(const Config &C, unsigned Task, AddStreamFn AddStream,
const FunctionImporter::ImportMapTy &ImportList,
const GVSummaryMapTy &DefinedGlobals,
MapVector<StringRef, BitcodeModule> *ModuleMap,
+ bool CodeGenOnly,
const std::vector<uint8_t> &CmdArgs = std::vector<uint8_t>());
Error finalizeOptimizationRemarks(
diff --git a/llvm/lib/LTO/LTO.cpp b/llvm/lib/LTO/LTO.cpp
index a88124dacfaefd..f4c25f80811a85 100644
--- a/llvm/lib/LTO/LTO.cpp
+++ b/llvm/lib/LTO/LTO.cpp
@@ -1473,7 +1473,8 @@ class InProcessThinBackend : public ThinBackendProc {
return MOrErr.takeError();
return thinBackend(Conf, Task, AddStream, **MOrErr, CombinedIndex,
- ImportList, DefinedGlobals, &ModuleMap);
+ ImportList, DefinedGlobals, &ModuleMap,
+ Conf.CodeGenOnly);
};
auto ModuleID = BM.getModuleIdentifier();
@@ -1839,45 +1840,49 @@ Error LTO::runThinLTO(AddStreamFn AddStream, FileCache Cache,
TimeTraceScopeExit.release();
- std::unique_ptr<ThinBackendProc> BackendProc =
- ThinLTO.Backend(Conf, ThinLTO.CombinedIndex, ModuleToDefinedGVSummaries,
- AddStream, Cache);
-
auto &ModuleMap =
ThinLTO.ModulesToCompile ? *ThinLTO.ModulesToCompile : ThinLTO.ModuleMap;
- auto ProcessOneModule = [&](int I) -> Error {
- auto &Mod = *(ModuleMap.begin() + I);
- // Tasks 0 through ParallelCodeGenParallelismLevel-1 are reserved for
- // combined module and parallel code generation partitions.
- return BackendProc->start(RegularLTO.ParallelCodeGenParallelismLevel + I,
- Mod.second, ImportLists[Mod.first],
- ExportLists[Mod.first], ResolvedODR[Mod.first],
- ThinLTO.ModuleMap);
+ auto RunBackends = [&](ThinBackendProc *BackendProcess) -> Error {
+ auto ProcessOneModule = [&](int I) -> Error {
+ auto &Mod = *(ModuleMap.begin() + I);
+ // Tasks 0 through ParallelCodeGenParallelismLevel-1 are reserved for
+ // combined module and parallel code generation partitions.
+ return BackendProcess->start(
+ RegularLTO.ParallelCodeGenParallelismLevel + I, Mod.second,
+ ImportLists[Mod.first], ExportLists[Mod.first],
+ ResolvedODR[Mod.first], ThinLTO.ModuleMap);
+ };
+
+ if (BackendProcess->getThreadCount() == 1) {
+ // Process the modules in the order they were provided on the
+ // command-line. It is important for this codepath to be used for
+ // WriteIndexesThinBackend, to ensure the emitted LinkedObjectsFile lists
+ // ThinLTO objects in the same order as the inputs, which otherwise would
+ // affect the final link order.
+ for (int I = 0, E = ModuleMap.size(); I != E; ++I)
+ if (Error E = ProcessOneModule(I))
+ return E;
+ } else {
+ // When executing in parallel, process largest bitsize modules first to
+ // improve parallelism, and avoid starving the thread pool near the end.
+ // This saves about 15 sec on a 36-core machine while link `clang.exe`
+ // (out of 100 sec).
+ std::vector<BitcodeModule *> ModulesVec;
+ ModulesVec.reserve(ModuleMap.size());
+ for (auto &Mod : ModuleMap)
+ ModulesVec.push_back(&Mod.second);
+ for (int I : generateModulesOrdering(ModulesVec))
+ if (Error E = ProcessOneModule(I))
+ return E;
+ }
+ return BackendProcess->wait();
};
- if (BackendProc->getThreadCount() == 1) {
- // Process the modules in the order they were provided on the command-line.
- // It is important for this codepath to be used for WriteIndexesThinBackend,
- // to ensure the emitted LinkedObjectsFile lists ThinLTO objects in the same
- // order as the inputs, which otherwise would affect the final link order.
- for (int I = 0, E = ModuleMap.size(); I != E; ++I)
- if (Error E = ProcessOneModule(I))
- return E;
- } else {
- // When executing in parallel, process largest bitsize modules first to
- // improve parallelism, and avoid starving the thread pool near the end.
- // This saves about 15 sec on a 36-core machine while link `clang.exe` (out
- // of 100 sec).
- std::vector<BitcodeModule *> ModulesVec;
- ModulesVec.reserve(ModuleMap.size());
- for (auto &Mod : ModuleMap)
- ModulesVec.push_back(&Mod.second);
- for (int I : generateModulesOrdering(ModulesVec))
- if (Error E = ProcessOneModule(I))
- return E;
- }
- return BackendProc->wait();
+ std::unique_ptr<ThinBackendProc> BackendProc =
+ ThinLTO.Backend(Conf, ThinLTO.CombinedIndex, ModuleToDefinedGVSummaries,
+ AddStream, Cache);
+ return RunBackends(BackendProc.get());
}
Expected<std::unique_ptr<ToolOutputFile>> lto::setupLLVMOptimizationRemarks(
diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp
index 4e58cd369c3ac9..880567989baffb 100644
--- a/llvm/lib/LTO/LTOBackend.cpp
+++ b/llvm/lib/LTO/LTOBackend.cpp
@@ -565,7 +565,7 @@ Error lto::thinBackend(const Config &Conf, unsigned Task, AddStreamFn AddStream,
const FunctionImporter::ImportMapTy &ImportList,
const GVSummaryMapTy &DefinedGlobals,
MapVector<StringRef, BitcodeModule> *ModuleMap,
- const std::vector<uint8_t> &CmdArgs) {
+ bool CodeGenOnly, const std::vector<uint8_t> &CmdArgs) {
Expected<const Target *> TOrErr = initAndLookupTarget(Conf, Mod);
if (!TOrErr)
return TOrErr.takeError();
@@ -586,7 +586,9 @@ Error lto::thinBackend(const Config &Conf, unsigned Task, AddStreamFn AddStream,
Mod.setPartialSampleProfileRatio(CombinedIndex);
LLVM_DEBUG(dbgs() << "Running ThinLTO\n");
- if (Conf.CodeGenOnly) {
+ if (CodeGenOnly) {
+ // If CodeGenOnly is set, we only perform code generation and skip
+ // optimization.
codegen(Conf, TM.get(), AddStream, Task, Mod, CombinedIndex);
return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile));
}
|
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@llvm/pr-subscribers-clang Author: Kyungwoo Lee (kyulee-com) ChangesThis is NFC for #90933.
Depends on #90304. Full diff: https://github.com/llvm/llvm-project/pull/90934.diff 4 Files Affected:
diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index 7fa69420298160..a1909d45b4d944 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -1286,10 +1286,10 @@ static void runThinLTOBackend(
Conf.CGFileType = getCodeGenFileType(Action);
break;
}
- if (Error E =
- thinBackend(Conf, -1, AddStream, *M, *CombinedIndex, ImportList,
- ModuleToDefinedGVSummaries[M->getModuleIdentifier()],
- /* ModuleMap */ nullptr, CGOpts.CmdArgs)) {
+ if (Error E = thinBackend(
+ Conf, -1, AddStream, *M, *CombinedIndex, ImportList,
+ ModuleToDefinedGVSummaries[M->getModuleIdentifier()],
+ /* ModuleMap */ nullptr, Conf.CodeGenOnly, CGOpts.CmdArgs)) {
handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
errs() << "Error running ThinLTO backend: " << EIB.message() << '\n';
});
diff --git a/llvm/include/llvm/LTO/LTOBackend.h b/llvm/include/llvm/LTO/LTOBackend.h
index de89f4bb10dff2..8516398510d4b8 100644
--- a/llvm/include/llvm/LTO/LTOBackend.h
+++ b/llvm/include/llvm/LTO/LTOBackend.h
@@ -56,6 +56,7 @@ Error thinBackend(const Config &C, unsigned Task, AddStreamFn AddStream,
const FunctionImporter::ImportMapTy &ImportList,
const GVSummaryMapTy &DefinedGlobals,
MapVector<StringRef, BitcodeModule> *ModuleMap,
+ bool CodeGenOnly,
const std::vector<uint8_t> &CmdArgs = std::vector<uint8_t>());
Error finalizeOptimizationRemarks(
diff --git a/llvm/lib/LTO/LTO.cpp b/llvm/lib/LTO/LTO.cpp
index a88124dacfaefd..f4c25f80811a85 100644
--- a/llvm/lib/LTO/LTO.cpp
+++ b/llvm/lib/LTO/LTO.cpp
@@ -1473,7 +1473,8 @@ class InProcessThinBackend : public ThinBackendProc {
return MOrErr.takeError();
return thinBackend(Conf, Task, AddStream, **MOrErr, CombinedIndex,
- ImportList, DefinedGlobals, &ModuleMap);
+ ImportList, DefinedGlobals, &ModuleMap,
+ Conf.CodeGenOnly);
};
auto ModuleID = BM.getModuleIdentifier();
@@ -1839,45 +1840,49 @@ Error LTO::runThinLTO(AddStreamFn AddStream, FileCache Cache,
TimeTraceScopeExit.release();
- std::unique_ptr<ThinBackendProc> BackendProc =
- ThinLTO.Backend(Conf, ThinLTO.CombinedIndex, ModuleToDefinedGVSummaries,
- AddStream, Cache);
-
auto &ModuleMap =
ThinLTO.ModulesToCompile ? *ThinLTO.ModulesToCompile : ThinLTO.ModuleMap;
- auto ProcessOneModule = [&](int I) -> Error {
- auto &Mod = *(ModuleMap.begin() + I);
- // Tasks 0 through ParallelCodeGenParallelismLevel-1 are reserved for
- // combined module and parallel code generation partitions.
- return BackendProc->start(RegularLTO.ParallelCodeGenParallelismLevel + I,
- Mod.second, ImportLists[Mod.first],
- ExportLists[Mod.first], ResolvedODR[Mod.first],
- ThinLTO.ModuleMap);
+ auto RunBackends = [&](ThinBackendProc *BackendProcess) -> Error {
+ auto ProcessOneModule = [&](int I) -> Error {
+ auto &Mod = *(ModuleMap.begin() + I);
+ // Tasks 0 through ParallelCodeGenParallelismLevel-1 are reserved for
+ // combined module and parallel code generation partitions.
+ return BackendProcess->start(
+ RegularLTO.ParallelCodeGenParallelismLevel + I, Mod.second,
+ ImportLists[Mod.first], ExportLists[Mod.first],
+ ResolvedODR[Mod.first], ThinLTO.ModuleMap);
+ };
+
+ if (BackendProcess->getThreadCount() == 1) {
+ // Process the modules in the order they were provided on the
+ // command-line. It is important for this codepath to be used for
+ // WriteIndexesThinBackend, to ensure the emitted LinkedObjectsFile lists
+ // ThinLTO objects in the same order as the inputs, which otherwise would
+ // affect the final link order.
+ for (int I = 0, E = ModuleMap.size(); I != E; ++I)
+ if (Error E = ProcessOneModule(I))
+ return E;
+ } else {
+ // When executing in parallel, process largest bitsize modules first to
+ // improve parallelism, and avoid starving the thread pool near the end.
+ // This saves about 15 sec on a 36-core machine while link `clang.exe`
+ // (out of 100 sec).
+ std::vector<BitcodeModule *> ModulesVec;
+ ModulesVec.reserve(ModuleMap.size());
+ for (auto &Mod : ModuleMap)
+ ModulesVec.push_back(&Mod.second);
+ for (int I : generateModulesOrdering(ModulesVec))
+ if (Error E = ProcessOneModule(I))
+ return E;
+ }
+ return BackendProcess->wait();
};
- if (BackendProc->getThreadCount() == 1) {
- // Process the modules in the order they were provided on the command-line.
- // It is important for this codepath to be used for WriteIndexesThinBackend,
- // to ensure the emitted LinkedObjectsFile lists ThinLTO objects in the same
- // order as the inputs, which otherwise would affect the final link order.
- for (int I = 0, E = ModuleMap.size(); I != E; ++I)
- if (Error E = ProcessOneModule(I))
- return E;
- } else {
- // When executing in parallel, process largest bitsize modules first to
- // improve parallelism, and avoid starving the thread pool near the end.
- // This saves about 15 sec on a 36-core machine while link `clang.exe` (out
- // of 100 sec).
- std::vector<BitcodeModule *> ModulesVec;
- ModulesVec.reserve(ModuleMap.size());
- for (auto &Mod : ModuleMap)
- ModulesVec.push_back(&Mod.second);
- for (int I : generateModulesOrdering(ModulesVec))
- if (Error E = ProcessOneModule(I))
- return E;
- }
- return BackendProc->wait();
+ std::unique_ptr<ThinBackendProc> BackendProc =
+ ThinLTO.Backend(Conf, ThinLTO.CombinedIndex, ModuleToDefinedGVSummaries,
+ AddStream, Cache);
+ return RunBackends(BackendProc.get());
}
Expected<std::unique_ptr<ToolOutputFile>> lto::setupLLVMOptimizationRemarks(
diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp
index 4e58cd369c3ac9..880567989baffb 100644
--- a/llvm/lib/LTO/LTOBackend.cpp
+++ b/llvm/lib/LTO/LTOBackend.cpp
@@ -565,7 +565,7 @@ Error lto::thinBackend(const Config &Conf, unsigned Task, AddStreamFn AddStream,
const FunctionImporter::ImportMapTy &ImportList,
const GVSummaryMapTy &DefinedGlobals,
MapVector<StringRef, BitcodeModule> *ModuleMap,
- const std::vector<uint8_t> &CmdArgs) {
+ bool CodeGenOnly, const std::vector<uint8_t> &CmdArgs) {
Expected<const Target *> TOrErr = initAndLookupTarget(Conf, Mod);
if (!TOrErr)
return TOrErr.takeError();
@@ -586,7 +586,9 @@ Error lto::thinBackend(const Config &Conf, unsigned Task, AddStreamFn AddStream,
Mod.setPartialSampleProfileRatio(CombinedIndex);
LLVM_DEBUG(dbgs() << "Running ThinLTO\n");
- if (Conf.CodeGenOnly) {
+ if (CodeGenOnly) {
+ // If CodeGenOnly is set, we only perform code generation and skip
+ // optimization.
codegen(Conf, TM.get(), AddStream, Task, Mod, CombinedIndex);
return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile));
}
|
| @@ -56,6 +56,7 @@ Error thinBackend(const Config &C, unsigned Task, AddStreamFn AddStream, | |||
| const FunctionImporter::ImportMapTy &ImportList, | |||
| const GVSummaryMapTy &DefinedGlobals, | |||
| MapVector<StringRef, BitcodeModule> *ModuleMap, | |||
| bool CodeGenOnly, | |||
There was a problem hiding this comment.
nit: add a brief comment for CodeGenOnly parameter before method thinBackend.
teresajohnson
approved these changes
Oct 3, 2024
| @@ -586,7 +586,9 @@ Error lto::thinBackend(const Config &Conf, unsigned Task, AddStreamFn AddStream, | |||
| Mod.setPartialSampleProfileRatio(CombinedIndex); | |||
|
|
|||
| LLVM_DEBUG(dbgs() << "Running ThinLTO\n"); | |||
| if (Conf.CodeGenOnly) { | |||
| if (CodeGenOnly) { | |||
There was a problem hiding this comment.
Can you add a comment that this value may be different than the one in the provided Config.
kyulee-com
added a commit
that referenced
this pull request
Oct 9, 2024
This feature is enabled by `-codegen-data-thinlto-two-rounds`, which effectively runs the `-codegen-data-generate` and `-codegen-data-use` in two rounds to enable global outlining with ThinLTO. 1. The first round: Run both optimization + codegen with a scratch output. Before running codegen, we serialize the optimized bitcode modules to a temporary path. 2. From the scratch object files, we merge them into the codegen data. 3. The second round: Read the optimized bitcode modules and start the codegen only this time. Using the codegen data, the machine outliner effectively performs the global outlining. Depends on #90934, #110461 and #110463. This is a patch for https://discourse.llvm.org/t/rfc-enhanced-machine-outliner-part-2-thinlto-nolto/78753.
DanielCChen
pushed a commit
to DanielCChen/llvm-project
that referenced
this pull request
Oct 16, 2024
This feature is enabled by `-codegen-data-thinlto-two-rounds`, which effectively runs the `-codegen-data-generate` and `-codegen-data-use` in two rounds to enable global outlining with ThinLTO. 1. The first round: Run both optimization + codegen with a scratch output. Before running codegen, we serialize the optimized bitcode modules to a temporary path. 2. From the scratch object files, we merge them into the codegen data. 3. The second round: Read the optimized bitcode modules and start the codegen only this time. Using the codegen data, the machine outliner effectively performs the global outlining. Depends on llvm#90934, llvm#110461 and llvm#110463. This is a patch for https://discourse.llvm.org/t/rfc-enhanced-machine-outliner-part-2-thinlto-nolto/78753.
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This is NFC for #90933.
RunBackends, to group the backend operations into a single function.CodeGenOnlyargument to thinBackend, instead of depending on a configuration value.Depends on #90304.
This is a patch for https://discourse.llvm.org/t/rfc-enhanced-machine-outliner-part-2-thinlto-nolto/78753.