https://github.com/vikramRH created https://github.com/llvm/llvm-project/pull/210249
None >From 21debf8f853cef64680d3e412cee2f88ac2f9290 Mon Sep 17 00:00:00 2001 From: vikhegde <[email protected]> Date: Thu, 16 Jul 2026 16:23:49 +0530 Subject: [PATCH] [LTO] Add support for NewPM CodeGen --- llvm/lib/LTO/LTOBackend.cpp | 68 +++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp index 73697a9d0d446..8676fdcf638b5 100644 --- a/llvm/lib/LTO/LTOBackend.cpp +++ b/llvm/lib/LTO/LTOBackend.cpp @@ -22,8 +22,10 @@ #include "llvm/Bitcode/BitcodeReader.h" #include "llvm/Bitcode/BitcodeWriter.h" #include "llvm/CGData/CodeGenData.h" +#include "llvm/CodeGen/MachineModuleInfo.h" #include "llvm/IR/LLVMRemarkStreamer.h" #include "llvm/IR/LegacyPassManager.h" +#include "llvm/IR/ModuleSummaryIndex.h" #include "llvm/IR/PassManager.h" #include "llvm/IR/Verifier.h" #include "llvm/LTO/LTO.h" @@ -74,6 +76,10 @@ static cl::opt<bool> ThinLTOAssumeMerged( cl::desc("Assume the input has already undergone ThinLTO function " "importing and the other pre-optimization pipeline changes.")); +static cl::opt<bool> EnableNPMForBackend("enable-npm-for-backend", + cl::init(false), + cl::desc("Disable NPM for backend")); + static cl::list<std::string> SaveModulesList("filter-save-modules", cl::value_desc("module names"), cl::desc("Only save bitcode for module whose name without " @@ -434,6 +440,56 @@ bool lto::opt(const Config &Conf, TargetMachine *TM, unsigned Task, Module &Mod, return !Conf.PostOptModuleHook || Conf.PostOptModuleHook(Task, Mod); } +Error runBackendWithNewPM(TargetMachine *TM, Module &Mod, + std::unique_ptr<CachedFileStream> &Stream, + std::unique_ptr<ToolOutputFile> &DwoOut, + const Config &Conf, + const ModuleSummaryIndex &CombinedIndex) { + MachineModuleInfo MMI(TM); + PassInstrumentationCallbacks PIC; + MachineFunctionAnalysisManager MFAM; + LoopAnalysisManager LAM; + FunctionAnalysisManager FAM; + CGSCCAnalysisManager CGAM; + ModuleAnalysisManager MAM; + PassBuilder PB(TM, PipelineTuningOptions(), std::nullopt, &PIC); + + TargetLibraryInfoImpl TLII(Mod.getTargetTriple(), TM->Options.VecLib); + FAM.registerPass([&] { return TargetLibraryAnalysis(TLII); }); + MAM.registerPass([&] { return MachineModuleAnalysis(MMI); }); + MAM.registerPass([&] { + return RuntimeLibraryAnalysis( + Mod.getTargetTriple(), TM->Options.ExceptionModel, + TM->Options.FloatABIType, TM->Options.EABIVersion, + TM->Options.MCOptions.ABIName, TM->Options.VecLib); + }); + + if (!isEmptyModule(Mod)) + MAM.registerPass( + [&] { return ImmutableModuleSummaryIndexAnalysis(&CombinedIndex); }); + + PB.registerModuleAnalyses(MAM); + PB.registerCGSCCAnalyses(CGAM); + PB.registerFunctionAnalyses(FAM); + PB.registerLoopAnalyses(LAM); + PB.registerMachineFunctionAnalyses(MFAM); + PB.crossRegisterProxies(LAM, FAM, CGAM, MAM, &MFAM); + + ModulePassManager MPM; + FunctionPassManager FPM; + + if (Error Err = TM->buildCodeGenPipeline( + MPM, MAM, *Stream->OS, DwoOut ? &DwoOut->os() : nullptr, + Conf.CGFileType, CGPassBuilderOption(), MMI.getContext(), &PIC)) + return Err; + + MPM.run(Mod, MAM); + + if (DwoOut) + DwoOut->keep(); + return Error::success(); +} + static void codegen(const Config &Conf, TargetMachine *TM, AddStreamFn AddStream, unsigned Task, Module &Mod, const ModuleSummaryIndex &CombinedIndex) { @@ -480,6 +536,18 @@ static void codegen(const Config &Conf, TargetMachine *TM, // Stream->commit() is called. The commit function of CacheStream deletes // the raw stream, which is too early as streamers (e.g. MCAsmStreamer) // keep the pointer and may use it until their destruction. See #138194. + if (EnableNPMForBackend) { + if (!runBackendWithNewPM(TM, Mod, Stream, DwoOut, Conf, CombinedIndex)) { + // NPM success + if (Error Err = Stream->commit()) + report_fatal_error(std::move(Err)); + return; + } + + llvm::errs() + << "warning: New pass manager failed, falling back to legacy PM\n"; + } + { legacy::PassManager CodeGenPasses; TargetLibraryInfoImpl TLII(Mod.getTargetTriple(), TM->Options.VecLib); _______________________________________________ llvm-branch-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
