https://github.com/tianleliu created https://github.com/llvm/llvm-project/pull/175696
Only if module's name contains a string in -filter-print-modules, will its temps BC files be dumped. If -filter-print-modules= not set, all modules' BC files will be dumped. This feature is more useful for ThinLto when huge numbers of modules are built separately. Using -filter-print-modules= can reduce build time and size of generated files, even avoid crash if some other unrelated files have issues during BC files dumping. >From 212ae9590c14555c6a9329e8eec45216924063e8 Mon Sep 17 00:00:00 2001 From: tianleli <[email protected]> Date: Tue, 13 Jan 2026 09:28:03 +0800 Subject: [PATCH] [LTOBackend] Add -filter-print-modules= for save-temps to only dump specific modules' temps BC files. Only if module's name contains a string in -filter-print-modules, will its temps BC files be dumped. If -filter-print-modules= not set, all modules' BC files will be dumped. This feature is more useful for ThinLto when huge numbers of modules are built separately. Using -filter-print-modules= can reduce build time and size of generated files, even avoid crash if some other unrelated files have issues during BC files dumping. --- clang/test/CodeGen/thinlto-savetemps-mod.ll | 47 +++++++++++++++++++++ llvm/lib/LTO/LTOBackend.cpp | 22 ++++++++++ 2 files changed, 69 insertions(+) create mode 100644 clang/test/CodeGen/thinlto-savetemps-mod.ll diff --git a/clang/test/CodeGen/thinlto-savetemps-mod.ll b/clang/test/CodeGen/thinlto-savetemps-mod.ll new file mode 100644 index 0000000000000..cb5a4c2374822 --- /dev/null +++ b/clang/test/CodeGen/thinlto-savetemps-mod.ll @@ -0,0 +1,47 @@ +# RUN: rm -rf %t.dir +# RUN: split-file %s %t.dir && cd %t.dir +# RUN: %clang -c -flto=thin -O2 mymul.cpp -o mymul.o +# RUN: %clang -c -flto=thin -O2 myfoo.cpp -o myfoo.o +# RUN: %clang -shared -O2 -flto=thin mymul.o myfoo.o -o libmy.so -Wl,-plugin-opt=save-temps -Wl,-plugin-opt=-filter-print-modules=mymul +# RUN: ls -tr | FileCheck %s --check-prefix=MUL +# RUN: rm *.bc +# RUN: %clang -shared -O2 -flto=thin mymul.o myfoo.o -o libmy.so -Wl,-plugin-opt=save-temps -Wl,-plugin-opt=-filter-print-modules=mymul -Wl,-plugin-opt=-filter-print-modules=myfoo +# RUN: ls -tr | FileCheck %s --check-prefix=MUL_FOO +# RUN: rm *.bc +# RUN: %clang -shared -O2 -flto=thin mymul.o myfoo.o -o libmy.so -Wl,-plugin-opt=save-temps +# RUN: ls -tr | FileCheck %s --check-prefix=ALL + +# MUL-NOT: myfoo.o.{{[0-5]+}}{{.*}}.bc +# MUL-DAG: mymul.o.0.preopt.bc +# MUL-DAG: mymul.o.1.promote.bc +# MUL-DAG: mymul.o.2.internalize.bc +# MUL-DAG: mymul.o.3.import.bc +# MUL-DAG: mymul.o.4.opt.bc +# MUL-DAG: mymul.o.5.precodegen.bc +# MUL-NOT: myfoo.o.{{[0-5]+}}{{.*}}.bc + +# MUL_FOO-DAG: mymul.o.{{[0-5]+}}{{.*}}.bc +# MUL_FOO-DAG: myfoo.o.{{[0-5]+}}{{.*}}.bc + +# ALL-DAG: mymul.o.{{[0-5]+}}{{.*}}.bc +# ALL-DAG: myfoo.o.{{[0-5]+}}{{.*}}.bc + +#--- myfoo.h +__attribute__((visibility("default"))) long foo(long n); + +#--- myfoo.cpp +#include "myfoo.h" +#include "mymul.h" +__attribute__((visibility("default"))) long foo(long n) { + return mul(n,n+1); +} + +#--- mymul.h +long mul(int a, int b); + +#--- mymul.cpp +#include "mymul.h" +long mul(int a, int b) { + return a*a; +} + diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp index e998ac961e24a..a05e9f0d9038f 100644 --- a/llvm/lib/LTO/LTOBackend.cpp +++ b/llvm/lib/LTO/LTOBackend.cpp @@ -74,6 +74,12 @@ 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::list<std::string> + PrintModulesList("filter-print-modules", cl::value_desc("module names"), + cl::desc("Only print IR for module whose name " + "includes this for -save-temps options"), + cl::CommaSeparated, cl::Hidden); + namespace llvm { extern cl::opt<bool> NoPGOWarnMismatch; } @@ -103,6 +109,22 @@ Error Config::addSaveTemps(std::string OutputFileName, bool UseInputModulePath, // Keep track of the hook provided by the linker, which also needs to run. ModuleHookFn LinkerHook = Hook; Hook = [=](unsigned Task, const Module &M) { + // Check if specific modules (its name contains substring in + // PrintModulesList) here to dump save-temps only. + llvm::StringMap<bool> PrintModNamesMap; + for (const auto &name : PrintModulesList) { + PrintModNamesMap[name] = true; + } + bool ModNameMatch = false; + for (auto &entry : PrintModNamesMap) { + if (M.getName().contains(entry.first())) { + ModNameMatch = true; + LLVM_DEBUG(dbgs() << "Match " << M.getName() << "\n"); + break; + } + } + if (!PrintModNamesMap.empty() && !ModNameMatch) + return false; // If the linker's hook returned false, we need to pass that result // through. if (LinkerHook && !LinkerHook(Task, M)) _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
