From 5e08a76525b8f5e9aeb8b27d0466614abec070a9 Mon Sep 17 00:00:00 2001 From: Wang Nan Date: Sat, 26 Nov 2016 07:03:38 +0000 Subject: perf clang: Support compile IR to BPF object and add testcase getBPFObjectFromModule() is introduced to compile LLVM IR(Module) to BPF object. Add new testcase for it. Test result: $ ./buildperf/perf test -v clang 51: builtin clang support : 51.1: builtin clang compile C source to IR : --- start --- test child forked, pid 21822 test child finished with 0 ---- end ---- builtin clang support subtest 0: Ok 51.2: builtin clang compile C source to ELF object : --- start --- test child forked, pid 21823 test child finished with 0 ---- end ---- builtin clang support subtest 1: Ok Signed-off-by: Wang Nan Cc: Alexei Starovoitov Cc: He Kuang Cc: Jiri Olsa Cc: Joe Stringer Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/20161126070354.141764-15-wangnan0@huawei.com [ Remove redundant "Test" from entry descriptions ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/tests/clang.c | 6 ++++- tools/perf/util/c++/clang-c.h | 1 + tools/perf/util/c++/clang-test.cpp | 31 +++++++++++++++++++++----- tools/perf/util/c++/clang.cpp | 45 ++++++++++++++++++++++++++++++++++++++ tools/perf/util/c++/clang.h | 3 +++ 5 files changed, 79 insertions(+), 7 deletions(-) diff --git a/tools/perf/tests/clang.c b/tools/perf/tests/clang.c index 636d6d0e9037..f853e242a86c 100644 --- a/tools/perf/tests/clang.c +++ b/tools/perf/tests/clang.c @@ -12,6 +12,10 @@ static struct { .func = test__clang_to_IR, .desc = "builtin clang compile C source to IR", }, + { + .func = test__clang_to_obj, + .desc = "builtin clang compile C source to ELF object", + }, #endif }; @@ -33,7 +37,7 @@ int test__clang(int i __maybe_unused) return TEST_SKIP; } #else -int test__clang(int i __maybe_unused) +int test__clang(int i) { if (i < 0 || i >= (int)ARRAY_SIZE(clang_testcase_table)) return TEST_FAIL; diff --git a/tools/perf/util/c++/clang-c.h b/tools/perf/util/c++/clang-c.h index dcde4b564f3b..22b3936d1f09 100644 --- a/tools/perf/util/c++/clang-c.h +++ b/tools/perf/util/c++/clang-c.h @@ -9,6 +9,7 @@ extern void perf_clang__init(void); extern void perf_clang__cleanup(void); extern int test__clang_to_IR(void); +extern int test__clang_to_obj(void); #ifdef __cplusplus } diff --git a/tools/perf/util/c++/clang-test.cpp b/tools/perf/util/c++/clang-test.cpp index d84e760d2aab..9b11e8c82798 100644 --- a/tools/perf/util/c++/clang-test.cpp +++ b/tools/perf/util/c++/clang-test.cpp @@ -13,15 +13,13 @@ public: ~perf_clang_scope() {perf_clang__cleanup();} }; -extern "C" { - -int test__clang_to_IR(void) +static std::unique_ptr +__test__clang_to_IR(void) { - perf_clang_scope _scope; unsigned int kernel_version; if (fetch_kernel_version(&kernel_version, NULL, 0)) - return -1; + return std::unique_ptr(nullptr); std::string cflag_kver("-DLINUX_VERSION_CODE=" + std::to_string(kernel_version)); @@ -30,14 +28,35 @@ int test__clang_to_IR(void) perf::getModuleFromSource({cflag_kver.c_str()}, "perf-test.c", test_llvm__bpf_base_prog); + return M; +} + +extern "C" { +int test__clang_to_IR(void) +{ + perf_clang_scope _scope; + auto M = __test__clang_to_IR(); if (!M) return -1; - for (llvm::Function& F : *M) if (F.getName() == "bpf_func__SyS_epoll_wait") return 0; return -1; } +int test__clang_to_obj(void) +{ + perf_clang_scope _scope; + + auto M = __test__clang_to_IR(); + if (!M) + return -1; + + auto Buffer = perf::getBPFObjectFromModule(&*M); + if (!Buffer) + return -1; + return 0; +} + } diff --git a/tools/perf/util/c++/clang.cpp b/tools/perf/util/c++/clang.cpp index 715ca0a3dee0..2a1a75df204f 100644 --- a/tools/perf/util/c++/clang.cpp +++ b/tools/perf/util/c++/clang.cpp @@ -13,10 +13,15 @@ #include "clang/Frontend/CompilerInstance.h" #include "clang/Frontend/TextDiagnosticPrinter.h" #include "clang/Tooling/Tooling.h" +#include "llvm/IR/LegacyPassManager.h" #include "llvm/IR/Module.h" #include "llvm/Option/Option.h" #include "llvm/Support/FileSystem.h" #include "llvm/Support/ManagedStatic.h" +#include "llvm/Support/TargetRegistry.h" +#include "llvm/Support/TargetSelect.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetOptions.h" #include #include "clang.h" @@ -105,12 +110,52 @@ getModuleFromSource(llvm::opt::ArgStringList CFlags, StringRef Path) return getModuleFromSource(std::move(CFlags), Path, VFS); } +std::unique_ptr> +getBPFObjectFromModule(llvm::Module *Module) +{ + using namespace llvm; + + std::string TargetTriple("bpf-pc-linux"); + std::string Error; + const Target* Target = TargetRegistry::lookupTarget(TargetTriple, Error); + if (!Target) { + llvm::errs() << Error; + return std::unique_ptr>(nullptr); + } + + llvm::TargetOptions Opt; + TargetMachine *TargetMachine = + Target->createTargetMachine(TargetTriple, + "generic", "", + Opt, Reloc::Static); + + Module->setDataLayout(TargetMachine->createDataLayout()); + Module->setTargetTriple(TargetTriple); + + std::unique_ptr> Buffer(new SmallVector()); + raw_svector_ostream ostream(*Buffer); + + legacy::PassManager PM; + if (TargetMachine->addPassesToEmitFile(PM, ostream, + TargetMachine::CGFT_ObjectFile)) { + llvm::errs() << "TargetMachine can't emit a file of this type\n"; + return std::unique_ptr>(nullptr);; + } + PM.run(*Module); + + return std::move(Buffer); +} + } extern "C" { void perf_clang__init(void) { perf::LLVMCtx.reset(new llvm::LLVMContext()); + LLVMInitializeBPFTargetInfo(); + LLVMInitializeBPFTarget(); + LLVMInitializeBPFTargetMC(); + LLVMInitializeBPFAsmPrinter(); } void perf_clang__cleanup(void) diff --git a/tools/perf/util/c++/clang.h b/tools/perf/util/c++/clang.h index b4fc2a96b79d..dd8b0427550d 100644 --- a/tools/perf/util/c++/clang.h +++ b/tools/perf/util/c++/clang.h @@ -19,5 +19,8 @@ std::unique_ptr getModuleFromSource(opt::ArgStringList CFlags, StringRef Path); +std::unique_ptr> +getBPFObjectFromModule(llvm::Module *Module); + } #endif -- cgit v1.2.3