https://github.com/vikramRH updated https://github.com/llvm/llvm-project/pull/210248
>From 3318341ab7dfad79af6286146be3f91c738410a6 Mon Sep 17 00:00:00 2001 From: vikhegde <[email protected]> Date: Thu, 16 Jul 2026 16:12:34 +0530 Subject: [PATCH] [CodeGen] Implement fallback path for backend NPM run --- .../clang/Basic/DiagnosticFrontendKinds.td | 3 + clang/include/clang/Basic/DiagnosticGroups.td | 1 + clang/lib/CodeGen/BackendUtil.cpp | 55 ++++++++++++++----- 3 files changed, 45 insertions(+), 14 deletions(-) diff --git a/clang/include/clang/Basic/DiagnosticFrontendKinds.td b/clang/include/clang/Basic/DiagnosticFrontendKinds.td index a688b298f2bbd..2bda0e02fa0a5 100644 --- a/clang/include/clang/Basic/DiagnosticFrontendKinds.td +++ b/clang/include/clang/Basic/DiagnosticFrontendKinds.td @@ -129,6 +129,9 @@ def err_fe_unable_to_create_subtarget : Error< "unable to create subtarget: '%0'%select{ with features '%2'|}1">; def err_fe_unable_to_interface_with_target : Error< "unable to interface with target machine">; +def warn_fe_failed_new_pass_manager : Warning< + "new pass manager failed, retrying codegen with legacy PM">, + InGroup<NewPassManager>; def err_fe_unable_to_open_output : Error< "unable to open output file '%0': '%1'">; def warn_fe_macro_contains_embedded_newline : Warning< diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td index 79583534b9bbd..35ed6d82652f9 100644 --- a/clang/include/clang/Basic/DiagnosticGroups.td +++ b/clang/include/clang/Basic/DiagnosticGroups.td @@ -1793,6 +1793,7 @@ Results can be filtered by function name by passing // Compatibility flag name from old versions of Clang. def : DiagGroup<"frame-larger-than=", [BackendFrameLargerThan]>; def BackendPlugin : DiagGroup<"backend-plugin">; +def NewPassManager : DiagGroup<"new-pass-manager">; def RemarkBackendPlugin : DiagGroup<"remark-backend-plugin">; def BackendOptimizationRemark : DiagGroup<"pass">; def BackendOptimizationRemarkMissed : DiagGroup<"pass-missed">; diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp index 2b755fa916e55..95a73a793898e 100644 --- a/clang/lib/CodeGen/BackendUtil.cpp +++ b/clang/lib/CodeGen/BackendUtil.cpp @@ -194,10 +194,10 @@ class EmitAssemblyHelper { std::unique_ptr<raw_pwrite_stream> &OS, std::unique_ptr<llvm::ToolOutputFile> &DwoOS, CodeGenFileType CGFT); - void RunCodegenPipelineNewPM(BackendAction Action, - std::unique_ptr<raw_pwrite_stream> &OS, - std::unique_ptr<llvm::ToolOutputFile> &DwoOS, - CodeGenFileType CGFT); + Error RunCodegenPipelineNewPM(BackendAction Action, + std::unique_ptr<raw_pwrite_stream> &OS, + std::unique_ptr<llvm::ToolOutputFile> &DwoOS, + CodeGenFileType CGFT); void TimeCodegenPasses(llvm::function_ref<void()> RunPasses); /// Check whether we should emit a module summary for regular LTO. @@ -1249,10 +1249,14 @@ void EmitAssemblyHelper::RunCodegenPipeline( } if (CodeGenOpts.EnableNewPMCodeGen) { - RunCodegenPipelineNewPM(Action, OS, DwoOS, CGFT); - } else { - RunCodegenPipelineLegacy(Action, OS, DwoOS, CGFT); + if (!RunCodegenPipelineNewPM(Action, OS, DwoOS, CGFT)) + return; + + Diags.Report(diag::warn_fe_failed_new_pass_manager); } + + // NPM path (if enabled) failed to construct pipeline. retry with legacy PM. + RunCodegenPipelineLegacy(Action, OS, DwoOS, CGFT); } void EmitAssemblyHelper::RunCodegenPipelineLegacy( @@ -1292,7 +1296,7 @@ void EmitAssemblyHelper::RunCodegenPipelineLegacy( TimeCodegenPasses([&] { CodeGenPasses.run(*TheModule); }); } -void EmitAssemblyHelper::RunCodegenPipelineNewPM( +Error EmitAssemblyHelper::RunCodegenPipelineNewPM( BackendAction Action, std::unique_ptr<raw_pwrite_stream> &OS, std::unique_ptr<llvm::ToolOutputFile> &DwoOS, CodeGenFileType CGFT) { ModulePassManager MPM; @@ -1309,6 +1313,12 @@ void EmitAssemblyHelper::RunCodegenPipelineNewPM( TargetMachine *TMPointer = TM.get(); PassBuilder PB(TMPointer, PTOptions, std::nullopt, &PIC, CI.getVirtualFileSystemPtr()); + + StandardInstrumentations SI(TheModule->getContext(), + CodeGenOpts.DebugPassManager, + CodeGenOpts.VerifyEach); + SI.registerCallbacks(PIC, &MAM); + PB.registerModuleAnalyses(MAM); PB.registerCGSCCAnalyses(CGAM); PB.registerFunctionAnalyses(FAM); @@ -1316,17 +1326,34 @@ void EmitAssemblyHelper::RunCodegenPipelineNewPM( PB.registerMachineFunctionAnalyses(MFAM); PB.crossRegisterProxies(LAM, FAM, CGAM, MAM, &MFAM); + TargetLibraryInfoImpl TLII(TheModule->getTargetTriple()); + FAM.registerPass([&] { return TargetLibraryAnalysis(TLII); }); MAM.registerPass([&] { return MachineModuleAnalysis(MMI); }); + MAM.registerPass([&] { + const llvm::TargetOptions &Options = TM->Options; + return RuntimeLibraryAnalysis(TargetTriple, Options.ExceptionModel, + Options.FloatABIType, Options.EABIVersion, + Options.MCOptions.ABIName, Options.VecLib); + }); + + if (Error BuildPipelineError = TM->buildCodeGenPipeline( + MPM, MAM, *OS, DwoOS ? &DwoOS->os() : nullptr, CGFT, Opt, + MMI.getContext(), &PIC)) + return BuildPipelineError; - Error BuildPipelineError = - TM->buildCodeGenPipeline(MPM, MAM, *OS, DwoOS ? &DwoOS->os() : nullptr, - CGFT, Opt, MMI.getContext(), &PIC); - if (BuildPipelineError) { - Diags.Report(diag::err_fe_unable_to_interface_with_target); - return; + if (PrintPipelinePasses) { + std::string PipelineStr; + raw_string_ostream OutS(PipelineStr); + MPM.printPipeline(OutS, [&PIC](StringRef ClassName) { + auto PassName = PIC.getPassNameForClassName(ClassName); + return PassName.empty() ? ClassName : PassName; + }); + outs() << PipelineStr << '\n'; + return Error::success(); } TimeCodegenPasses([&] { MPM.run(*TheModule, MAM); }); + return Error::success(); } void EmitAssemblyHelper::TimeCodegenPasses( _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
