llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Jacob Lambert (lamb-j) <details> <summary>Changes</summary> Now that we have a commandline option dictating a second link step, (-relink-builtin-bitcode-postop), we can condition the module creation when linking in bitcode modules. This aims to improve performance by avoiding unnecessary linking --- Full diff: https://github.com/llvm/llvm-project/pull/72478.diff 2 Files Affected: - (modified) clang/lib/CodeGen/BackendUtil.cpp (+1-1) - (modified) clang/lib/CodeGen/CodeGenAction.cpp (+39-17) ``````````diff diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp index a7a47d17723cb73..f01a6514f6effb0 100644 --- a/clang/lib/CodeGen/BackendUtil.cpp +++ b/clang/lib/CodeGen/BackendUtil.cpp @@ -103,7 +103,7 @@ static cl::opt<bool> ClSanitizeOnOptimizerEarlyEP( cl::desc("Insert sanitizers on OptimizerEarlyEP."), cl::init(false)); // Re-link builtin bitcodes after optimization -static cl::opt<bool> ClRelinkBuiltinBitcodePostop( +cl::opt<bool> ClRelinkBuiltinBitcodePostop( "relink-builtin-bitcode-postop", cl::Optional, cl::desc("Re-link builtin bitcodes after optimization."), cl::init(false)); } diff --git a/clang/lib/CodeGen/CodeGenAction.cpp b/clang/lib/CodeGen/CodeGenAction.cpp index a31a271ed77d1ca..e3ceb3adbcc93a8 100644 --- a/clang/lib/CodeGen/CodeGenAction.cpp +++ b/clang/lib/CodeGen/CodeGenAction.cpp @@ -57,6 +57,10 @@ using namespace llvm; #define DEBUG_TYPE "codegenaction" +namespace llvm { +extern cl::opt<bool> ClRelinkBuiltinBitcodePostop; +} + namespace clang { class BackendConsumer; class ClangDiagnosticHandler final : public DiagnosticHandler { @@ -251,32 +255,50 @@ bool BackendConsumer::LinkInModules(llvm::Module *M, bool ShouldLinkFiles) { } CurLinkModule = LM.Module.get(); - - // TODO: If CloneModule() is updated to support cloning of unmaterialized - // modules, we can remove this bool Err; - if (Error E = CurLinkModule->materializeAll()) - return false; // Create a Clone to move to the linker, which preserves the original // linking modules, allowing them to be linked again in the future - // TODO: Add a ShouldCleanup option to make Cloning optional. When - // set, we can pass the original modules to the linker for cleanup - std::unique_ptr<llvm::Module> Clone = llvm::CloneModule(*LM.Module); + if (ClRelinkBuiltinBitcodePostop) { + // TODO: If CloneModule() is updated to support cloning of unmaterialized + // modules, we can remove this + if (Error E = CurLinkModule->materializeAll()) + return false; - if (LM.Internalize) { - Err = Linker::linkModules( + std::unique_ptr<llvm::Module> Clone = llvm::CloneModule(*LM.Module); + + if (LM.Internalize) { + Err = Linker::linkModules( *M, std::move(Clone), LM.LinkFlags, [](llvm::Module &M, const llvm::StringSet<> &GVS) { - internalizeModule(M, [&GVS](const llvm::GlobalValue &GV) { - return !GV.hasName() || (GVS.count(GV.getName()) == 0); - }); + internalizeModule(M, [&GVS](const llvm::GlobalValue &GV) { + return !GV.hasName() || + (GVS.count(GV.getName()) == 0); + }); }); - } else - Err = Linker::linkModules(*M, std::move(Clone), LM.LinkFlags); + } else + Err = Linker::linkModules(*M, std::move(Clone), LM.LinkFlags); - if (Err) - return true; + if (Err) + return true; + } + // Otherwise we can link (and clean up) the original modules + else { + if (LM.Internalize) { + Err = Linker::linkModules( + *M, std::move(LM.Module), LM.LinkFlags, + [](llvm::Module &M, const llvm::StringSet<> &GVS) { + internalizeModule(M, [&GVS](const llvm::GlobalValue &GV) { + return !GV.hasName() || + (GVS.count(GV.getName()) == 0); + }); + }); + } else + Err = Linker::linkModules(*M, std::move(LM.Module), LM.LinkFlags); + + if (Err) + return true; + } } return false; // success `````````` </details> https://github.com/llvm/llvm-project/pull/72478 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
