| //===-- cc1_main.cpp - Clang CC1 Compiler Frontend ------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This is the entry point to the clang -cc1 functionality, which implements the |
| // core compiler functionality along with a number of additional tools for |
| // demonstration and testing purposes. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/Basic/Stack.h" |
| #include "clang/Basic/TargetOptions.h" |
| #include "clang/CodeGen/ObjectFilePCHContainerOperations.h" |
| #include "clang/Config/config.h" |
| #include "clang/Driver/DriverDiagnostic.h" |
| #include "clang/Driver/Options.h" |
| #include "clang/Frontend/CompilerInstance.h" |
| #include "clang/Frontend/CompilerInvocation.h" |
| #include "clang/Frontend/FrontendDiagnostic.h" |
| #include "clang/Frontend/TextDiagnosticBuffer.h" |
| #include "clang/Frontend/TextDiagnosticPrinter.h" |
| #include "clang/Frontend/Utils.h" |
| #include "clang/FrontendTool/Utils.h" |
| #include "llvm/ADT/Statistic.h" |
| #include "llvm/Config/llvm-config.h" |
| #include "llvm/LinkAllPasses.h" |
| #include "llvm/MC/TargetRegistry.h" |
| #include "llvm/Option/Arg.h" |
| #include "llvm/Option/ArgList.h" |
| #include "llvm/Option/OptTable.h" |
| #include "llvm/Support/BuryPointer.h" |
| #include "llvm/Support/Compiler.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/ManagedStatic.h" |
| #include "llvm/Support/Path.h" |
| #include "llvm/Support/Process.h" |
| #include "llvm/Support/Signals.h" |
| #include "llvm/Support/TargetSelect.h" |
| #include "llvm/Support/TimeProfiler.h" |
| #include "llvm/Support/Timer.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include "llvm/Target/TargetMachine.h" |
| #include <cstdio> |
| |
| #ifdef CLANG_HAVE_RLIMITS |
| #include <sys/resource.h> |
| #endif |
| |
| using namespace clang; |
| using namespace llvm::opt; |
| |
| //===----------------------------------------------------------------------===// |
| // Main driver |
| //===----------------------------------------------------------------------===// |
| |
| static void LLVMErrorHandler(void *UserData, const char *Message, |
| bool GenCrashDiag) { |
| DiagnosticsEngine &Diags = *static_cast<DiagnosticsEngine*>(UserData); |
| |
| Diags.Report(diag::err_fe_error_backend) << Message; |
| |
| // Run the interrupt handlers to make sure any special cleanups get done, in |
| // particular that we remove files registered with RemoveFileOnSignal. |
| llvm::sys::RunInterruptHandlers(); |
| |
| // We cannot recover from llvm errors. When reporting a fatal error, exit |
| // with status 70 to generate crash diagnostics. For BSD systems this is |
| // defined as an internal software error. Otherwise, exit with status 1. |
| llvm::sys::Process::Exit(GenCrashDiag ? 70 : 1); |
| } |
| |
| #ifdef CLANG_HAVE_RLIMITS |
| #if defined(__linux__) && defined(__PIE__) |
| static size_t getCurrentStackAllocation() { |
| // If we can't compute the current stack usage, allow for 512K of command |
| // line arguments and environment. |
| size_t Usage = 512 * 1024; |
| if (FILE *StatFile = fopen("/proc/self/stat", "r")) { |
| // We assume that the stack extends from its current address to the end of |
| // the environment space. In reality, there is another string literal (the |
| // program name) after the environment, but this is close enough (we only |
| // need to be within 100K or so). |
| unsigned long StackPtr, EnvEnd; |
| // Disable silly GCC -Wformat warning that complains about length |
| // modifiers on ignored format specifiers. We want to retain these |
| // for documentation purposes even though they have no effect. |
| #if defined(__GNUC__) && !defined(__clang__) |
| #pragma GCC diagnostic push |
| #pragma GCC diagnostic ignored "-Wformat" |
| #endif |
| if (fscanf(StatFile, |
| "%*d %*s %*c %*d %*d %*d %*d %*d %*u %*lu %*lu %*lu %*lu %*lu " |
| "%*lu %*ld %*ld %*ld %*ld %*ld %*ld %*llu %*lu %*ld %*lu %*lu " |
| "%*lu %*lu %lu %*lu %*lu %*lu %*lu %*lu %*llu %*lu %*lu %*d %*d " |
| "%*u %*u %*llu %*lu %*ld %*lu %*lu %*lu %*lu %*lu %*lu %lu %*d", |
| &StackPtr, &EnvEnd) == 2) { |
| #if defined(__GNUC__) && !defined(__clang__) |
| #pragma GCC diagnostic pop |
| #endif |
| Usage = StackPtr < EnvEnd ? EnvEnd - StackPtr : StackPtr - EnvEnd; |
| } |
| fclose(StatFile); |
| } |
| return Usage; |
| } |
| |
| #include <alloca.h> |
| |
| LLVM_ATTRIBUTE_NOINLINE |
| static void ensureStackAddressSpace() { |
| // Linux kernels prior to 4.1 will sometimes locate the heap of a PIE binary |
| // relatively close to the stack (they are only guaranteed to be 128MiB |
| // apart). This results in crashes if we happen to heap-allocate more than |
| // 128MiB before we reach our stack high-water mark. |
| // |
| // To avoid these crashes, ensure that we have sufficient virtual memory |
| // pages allocated before we start running. |
| size_t Curr = getCurrentStackAllocation(); |
| const int kTargetStack = DesiredStackSize - 256 * 1024; |
| if (Curr < kTargetStack) { |
| volatile char *volatile Alloc = |
| static_cast<volatile char *>(alloca(kTargetStack - Curr)); |
| Alloc[0] = 0; |
| Alloc[kTargetStack - Curr - 1] = 0; |
| } |
| } |
| #else |
| static void ensureStackAddressSpace() {} |
| #endif |
| |
| /// Attempt to ensure that we have at least 8MiB of usable stack space. |
| static void ensureSufficientStack() { |
| struct rlimit rlim; |
| if (getrlimit(RLIMIT_STACK, &rlim) != 0) |
| return; |
| |
| // Increase the soft stack limit to our desired level, if necessary and |
| // possible. |
| if (rlim.rlim_cur != RLIM_INFINITY && |
| rlim.rlim_cur < rlim_t(DesiredStackSize)) { |
| // Try to allocate sufficient stack. |
| if (rlim.rlim_max == RLIM_INFINITY || |
| rlim.rlim_max >= rlim_t(DesiredStackSize)) |
| rlim.rlim_cur = DesiredStackSize; |
| else if (rlim.rlim_cur == rlim.rlim_max) |
| return; |
| else |
| rlim.rlim_cur = rlim.rlim_max; |
| |
| if (setrlimit(RLIMIT_STACK, &rlim) != 0 || |
| rlim.rlim_cur != DesiredStackSize) |
| return; |
| } |
| |
| // We should now have a stack of size at least DesiredStackSize. Ensure |
| // that we can actually use that much, if necessary. |
| ensureStackAddressSpace(); |
| } |
| #else |
| static void ensureSufficientStack() {} |
| #endif |
| |
| /// Print supported cpus of the given target. |
| static int PrintSupportedCPUs(std::string TargetStr) { |
| std::string Error; |
| const llvm::Target *TheTarget = |
| llvm::TargetRegistry::lookupTarget(TargetStr, Error); |
| if (!TheTarget) { |
| llvm::errs() << Error; |
| return 1; |
| } |
| |
| // the target machine will handle the mcpu printing |
| llvm::TargetOptions Options; |
| std::unique_ptr<llvm::TargetMachine> TheTargetMachine( |
| TheTarget->createTargetMachine(TargetStr, "", "+cpuhelp", Options, None)); |
| return 0; |
| } |
| |
| int cc1_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) { |
| ensureSufficientStack(); |
| |
| std::unique_ptr<CompilerInstance> Clang(new CompilerInstance()); |
| IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs()); |
| |
| // Register the support for object-file-wrapped Clang modules. |
| auto PCHOps = Clang->getPCHContainerOperations(); |
| PCHOps->registerWriter(std::make_unique<ObjectFilePCHContainerWriter>()); |
| PCHOps->registerReader(std::make_unique<ObjectFilePCHContainerReader>()); |
| |
| // Initialize targets first, so that --version shows registered targets. |
| llvm::InitializeAllTargets(); |
| llvm::InitializeAllTargetMCs(); |
| llvm::InitializeAllAsmPrinters(); |
| llvm::InitializeAllAsmParsers(); |
| |
| // Buffer diagnostics from argument parsing so that we can output them using a |
| // well formed diagnostic object. |
| IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions(); |
| TextDiagnosticBuffer *DiagsBuffer = new TextDiagnosticBuffer; |
| DiagnosticsEngine Diags(DiagID, &*DiagOpts, DiagsBuffer); |
| |
| // Setup round-trip remarks for the DiagnosticsEngine used in CreateFromArgs. |
| if (find(Argv, StringRef("-Rround-trip-cc1-args")) != Argv.end()) |
| Diags.setSeverity(diag::remark_cc1_round_trip_generated, |
| diag::Severity::Remark, {}); |
| |
| bool Success = CompilerInvocation::CreateFromArgs(Clang->getInvocation(), |
| Argv, Diags, Argv0); |
| |
| if (Clang->getFrontendOpts().TimeTrace) { |
| llvm::timeTraceProfilerInitialize( |
| Clang->getFrontendOpts().TimeTraceGranularity, Argv0); |
| } |
| // --print-supported-cpus takes priority over the actual compilation. |
| if (Clang->getFrontendOpts().PrintSupportedCPUs) |
| return PrintSupportedCPUs(Clang->getTargetOpts().Triple); |
| |
| // Infer the builtin include path if unspecified. |
| if (Clang->getHeaderSearchOpts().UseBuiltinIncludes && |
| Clang->getHeaderSearchOpts().ResourceDir.empty()) |
| Clang->getHeaderSearchOpts().ResourceDir = |
| CompilerInvocation::GetResourcesPath(Argv0, MainAddr); |
| |
| // Create the actual diagnostics engine. |
| Clang->createDiagnostics(); |
| if (!Clang->hasDiagnostics()) |
| return 1; |
| |
| // Set an error handler, so that any LLVM backend diagnostics go through our |
| // error handler. |
| llvm::install_fatal_error_handler(LLVMErrorHandler, |
| static_cast<void*>(&Clang->getDiagnostics())); |
| |
| DiagsBuffer->FlushDiagnostics(Clang->getDiagnostics()); |
| if (!Success) |
| return 1; |
| |
| // Execute the frontend actions. |
| { |
| llvm::TimeTraceScope TimeScope("ExecuteCompiler"); |
| Success = ExecuteCompilerInvocation(Clang.get()); |
| } |
| |
| // If any timers were active but haven't been destroyed yet, print their |
| // results now. This happens in -disable-free mode. |
| llvm::TimerGroup::printAll(llvm::errs()); |
| llvm::TimerGroup::clearAll(); |
| |
| if (llvm::timeTraceProfilerEnabled()) { |
| SmallString<128> Path(Clang->getFrontendOpts().OutputFile); |
| llvm::sys::path::replace_extension(Path, "json"); |
| if (auto profilerOutput = Clang->createOutputFile( |
| Path.str(), /*Binary=*/false, /*RemoveFileOnSignal=*/false, |
| /*useTemporary=*/false)) { |
| llvm::timeTraceProfilerWrite(*profilerOutput); |
| // FIXME(ibiryukov): make profilerOutput flush in destructor instead. |
| profilerOutput->flush(); |
| llvm::timeTraceProfilerCleanup(); |
| Clang->clearOutputFiles(false); |
| } |
| } |
| |
| // Our error handler depends on the Diagnostics object, which we're |
| // potentially about to delete. Uninstall the handler now so that any |
| // later errors use the default handling behavior instead. |
| llvm::remove_fatal_error_handler(); |
| |
| // When running with -disable-free, don't do any destruction or shutdown. |
| if (Clang->getFrontendOpts().DisableFree) { |
| llvm::BuryPointer(std::move(Clang)); |
| return !Success; |
| } |
| |
| return !Success; |
| } |