1 //===-- ClangExpressionParser.cpp -------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 // C Includes
11 // C++ Includes
12 // Other libraries and framework includes
13 #include "clang/AST/ASTContext.h"
14 #include "clang/AST/ASTDiagnostic.h"
15 #include "clang/AST/ExternalASTSource.h"
16 #include "clang/Basic/DiagnosticIDs.h"
17 #include "clang/Basic/FileManager.h"
18 #include "clang/Basic/SourceLocation.h"
19 #include "clang/Basic/TargetInfo.h"
20 #include "clang/Basic/Version.h"
21 #include "clang/CodeGen/CodeGenAction.h"
22 #include "clang/CodeGen/ModuleBuilder.h"
23 #include "clang/Edit/Commit.h"
24 #include "clang/Edit/EditedSource.h"
25 #include "clang/Edit/EditsReceiver.h"
26 #include "clang/Frontend/CompilerInstance.h"
27 #include "clang/Frontend/CompilerInvocation.h"
28 #include "clang/Frontend/FrontendActions.h"
29 #include "clang/Frontend/FrontendDiagnostic.h"
30 #include "clang/Frontend/FrontendPluginRegistry.h"
31 #include "clang/Frontend/TextDiagnosticBuffer.h"
32 #include "clang/Frontend/TextDiagnosticPrinter.h"
33 #include "clang/Lex/Preprocessor.h"
34 #include "clang/Parse/ParseAST.h"
35 #include "clang/Rewrite/Core/Rewriter.h"
36 #include "clang/Rewrite/Frontend/FrontendActions.h"
37 #include "clang/Sema/SemaConsumer.h"
38 
39 #include "llvm/ADT/StringRef.h"
40 #include "llvm/ExecutionEngine/ExecutionEngine.h"
41 #include "llvm/Support/Debug.h"
42 #include "llvm/Support/FileSystem.h"
43 #include "llvm/Support/TargetSelect.h"
44 
45 #pragma clang diagnostic push
46 #pragma clang diagnostic ignored "-Wglobal-constructors"
47 #include "llvm/ExecutionEngine/MCJIT.h"
48 #pragma clang diagnostic pop
49 
50 #include "llvm/IR/LLVMContext.h"
51 #include "llvm/IR/Module.h"
52 #include "llvm/Support/DynamicLibrary.h"
53 #include "llvm/Support/ErrorHandling.h"
54 #include "llvm/Support/Host.h"
55 #include "llvm/Support/MemoryBuffer.h"
56 #include "llvm/Support/Signals.h"
57 
58 // Project includes
59 #include "ClangDiagnostic.h"
60 #include "ClangExpressionParser.h"
61 
62 #include "ClangASTSource.h"
63 #include "ClangExpressionDeclMap.h"
64 #include "ClangExpressionHelper.h"
65 #include "ClangModulesDeclVendor.h"
66 #include "ClangPersistentVariables.h"
67 #include "IRForTarget.h"
68 
69 #include "lldb/Core/Debugger.h"
70 #include "lldb/Core/Disassembler.h"
71 #include "lldb/Core/Module.h"
72 #include "lldb/Core/StreamFile.h"
73 #include "lldb/Expression/IRDynamicChecks.h"
74 #include "lldb/Expression/IRExecutionUnit.h"
75 #include "lldb/Expression/IRInterpreter.h"
76 #include "lldb/Host/File.h"
77 #include "lldb/Host/HostInfo.h"
78 #include "lldb/Symbol/ClangASTContext.h"
79 #include "lldb/Symbol/SymbolVendor.h"
80 #include "lldb/Target/ExecutionContext.h"
81 #include "lldb/Target/Language.h"
82 #include "lldb/Target/ObjCLanguageRuntime.h"
83 #include "lldb/Target/Process.h"
84 #include "lldb/Target/Target.h"
85 #include "lldb/Target/ThreadPlanCallFunction.h"
86 #include "lldb/Utility/DataBufferHeap.h"
87 #include "lldb/Utility/LLDBAssert.h"
88 #include "lldb/Utility/Log.h"
89 #include "lldb/Utility/Stream.h"
90 #include "lldb/Utility/StreamString.h"
91 #include "lldb/Utility/StringList.h"
92 
93 using namespace clang;
94 using namespace llvm;
95 using namespace lldb_private;
96 
97 //===----------------------------------------------------------------------===//
98 // Utility Methods for Clang
99 //===----------------------------------------------------------------------===//
100 
101 class ClangExpressionParser::LLDBPreprocessorCallbacks : public PPCallbacks {
102   ClangModulesDeclVendor &m_decl_vendor;
103   ClangPersistentVariables &m_persistent_vars;
104   StreamString m_error_stream;
105   bool m_has_errors = false;
106 
107 public:
108   LLDBPreprocessorCallbacks(ClangModulesDeclVendor &decl_vendor,
109                             ClangPersistentVariables &persistent_vars)
110       : m_decl_vendor(decl_vendor), m_persistent_vars(persistent_vars) {}
111 
112   void moduleImport(SourceLocation import_location, clang::ModuleIdPath path,
113                     const clang::Module * /*null*/) override {
114     std::vector<ConstString> string_path;
115 
116     for (const std::pair<IdentifierInfo *, SourceLocation> &component : path) {
117       string_path.push_back(ConstString(component.first->getName()));
118     }
119 
120     StreamString error_stream;
121 
122     ClangModulesDeclVendor::ModuleVector exported_modules;
123 
124     if (!m_decl_vendor.AddModule(string_path, &exported_modules,
125                                  m_error_stream)) {
126       m_has_errors = true;
127     }
128 
129     for (ClangModulesDeclVendor::ModuleID module : exported_modules) {
130       m_persistent_vars.AddHandLoadedClangModule(module);
131     }
132   }
133 
134   bool hasErrors() { return m_has_errors; }
135 
136   llvm::StringRef getErrorString() { return m_error_stream.GetString(); }
137 };
138 
139 class ClangDiagnosticManagerAdapter : public clang::DiagnosticConsumer {
140 public:
141   ClangDiagnosticManagerAdapter()
142       : m_passthrough(new clang::TextDiagnosticBuffer) {}
143 
144   ClangDiagnosticManagerAdapter(
145       const std::shared_ptr<clang::TextDiagnosticBuffer> &passthrough)
146       : m_passthrough(passthrough) {}
147 
148   void ResetManager(DiagnosticManager *manager = nullptr) {
149     m_manager = manager;
150   }
151 
152   void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
153                         const clang::Diagnostic &Info) {
154     if (m_manager) {
155       llvm::SmallVector<char, 32> diag_str;
156       Info.FormatDiagnostic(diag_str);
157       diag_str.push_back('\0');
158       const char *data = diag_str.data();
159 
160       lldb_private::DiagnosticSeverity severity;
161       bool make_new_diagnostic = true;
162 
163       switch (DiagLevel) {
164       case DiagnosticsEngine::Level::Fatal:
165       case DiagnosticsEngine::Level::Error:
166         severity = eDiagnosticSeverityError;
167         break;
168       case DiagnosticsEngine::Level::Warning:
169         severity = eDiagnosticSeverityWarning;
170         break;
171       case DiagnosticsEngine::Level::Remark:
172       case DiagnosticsEngine::Level::Ignored:
173         severity = eDiagnosticSeverityRemark;
174         break;
175       case DiagnosticsEngine::Level::Note:
176         m_manager->AppendMessageToDiagnostic(data);
177         make_new_diagnostic = false;
178       }
179       if (make_new_diagnostic) {
180         ClangDiagnostic *new_diagnostic =
181             new ClangDiagnostic(data, severity, Info.getID());
182         m_manager->AddDiagnostic(new_diagnostic);
183 
184         // Don't store away warning fixits, since the compiler doesn't have
185         // enough context in an expression for the warning to be useful.
186         // FIXME: Should we try to filter out FixIts that apply to our generated
187         // code, and not the user's expression?
188         if (severity == eDiagnosticSeverityError) {
189           size_t num_fixit_hints = Info.getNumFixItHints();
190           for (size_t i = 0; i < num_fixit_hints; i++) {
191             const clang::FixItHint &fixit = Info.getFixItHint(i);
192             if (!fixit.isNull())
193               new_diagnostic->AddFixitHint(fixit);
194           }
195         }
196       }
197     }
198 
199     m_passthrough->HandleDiagnostic(DiagLevel, Info);
200   }
201 
202   void FlushDiagnostics(DiagnosticsEngine &Diags) {
203     m_passthrough->FlushDiagnostics(Diags);
204   }
205 
206   DiagnosticConsumer *clone(DiagnosticsEngine &Diags) const {
207     return new ClangDiagnosticManagerAdapter(m_passthrough);
208   }
209 
210   clang::TextDiagnosticBuffer *GetPassthrough() { return m_passthrough.get(); }
211 
212 private:
213   DiagnosticManager *m_manager = nullptr;
214   std::shared_ptr<clang::TextDiagnosticBuffer> m_passthrough;
215 };
216 
217 //===----------------------------------------------------------------------===//
218 // Implementation of ClangExpressionParser
219 //===----------------------------------------------------------------------===//
220 
221 ClangExpressionParser::ClangExpressionParser(ExecutionContextScope *exe_scope,
222                                              Expression &expr,
223                                              bool generate_debug_info)
224     : ExpressionParser(exe_scope, expr, generate_debug_info), m_compiler(),
225       m_code_generator(), m_pp_callbacks(nullptr) {
226   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
227 
228   // We can't compile expressions without a target.  So if the exe_scope is
229   // null or doesn't have a target, then we just need to get out of here.  I'll
230   // lldb_assert and not make any of the compiler objects since
231   // I can't return errors directly from the constructor.  Further calls will
232   // check if the compiler was made and
233   // bag out if it wasn't.
234 
235   if (!exe_scope) {
236     lldb_assert(exe_scope, "Can't make an expression parser with a null scope.",
237                 __FUNCTION__, __FILE__, __LINE__);
238     return;
239   }
240 
241   lldb::TargetSP target_sp;
242   target_sp = exe_scope->CalculateTarget();
243   if (!target_sp) {
244     lldb_assert(target_sp.get(),
245                 "Can't make an expression parser with a null target.",
246                 __FUNCTION__, __FILE__, __LINE__);
247     return;
248   }
249 
250   // 1. Create a new compiler instance.
251   m_compiler.reset(new CompilerInstance());
252   lldb::LanguageType frame_lang =
253       expr.Language(); // defaults to lldb::eLanguageTypeUnknown
254   bool overridden_target_opts = false;
255   lldb_private::LanguageRuntime *lang_rt = nullptr;
256 
257   std::string abi;
258   ArchSpec target_arch;
259   target_arch = target_sp->GetArchitecture();
260 
261   const auto target_machine = target_arch.GetMachine();
262 
263   // If the expression is being evaluated in the context of an existing stack
264   // frame, we introspect to see if the language runtime is available.
265 
266   lldb::StackFrameSP frame_sp = exe_scope->CalculateStackFrame();
267   lldb::ProcessSP process_sp = exe_scope->CalculateProcess();
268 
269   // Make sure the user hasn't provided a preferred execution language with
270   // `expression --language X -- ...`
271   if (frame_sp && frame_lang == lldb::eLanguageTypeUnknown)
272     frame_lang = frame_sp->GetLanguage();
273 
274   if (process_sp && frame_lang != lldb::eLanguageTypeUnknown) {
275     lang_rt = process_sp->GetLanguageRuntime(frame_lang);
276     if (log)
277       log->Printf("Frame has language of type %s",
278                   Language::GetNameForLanguageType(frame_lang));
279   }
280 
281   // 2. Configure the compiler with a set of default options that are
282   // appropriate for most situations.
283   if (target_arch.IsValid()) {
284     std::string triple = target_arch.GetTriple().str();
285     m_compiler->getTargetOpts().Triple = triple;
286     if (log)
287       log->Printf("Using %s as the target triple",
288                   m_compiler->getTargetOpts().Triple.c_str());
289   } else {
290     // If we get here we don't have a valid target and just have to guess.
291     // Sometimes this will be ok to just use the host target triple (when we
292     // evaluate say "2+3", but other expressions like breakpoint conditions and
293     // other things that _are_ target specific really shouldn't just be using
294     // the host triple. In such a case the language runtime should expose an
295     // overridden options set (3), below.
296     m_compiler->getTargetOpts().Triple = llvm::sys::getDefaultTargetTriple();
297     if (log)
298       log->Printf("Using default target triple of %s",
299                   m_compiler->getTargetOpts().Triple.c_str());
300   }
301   // Now add some special fixes for known architectures: Any arm32 iOS
302   // environment, but not on arm64
303   if (m_compiler->getTargetOpts().Triple.find("arm64") == std::string::npos &&
304       m_compiler->getTargetOpts().Triple.find("arm") != std::string::npos &&
305       m_compiler->getTargetOpts().Triple.find("ios") != std::string::npos) {
306     m_compiler->getTargetOpts().ABI = "apcs-gnu";
307   }
308   // Supported subsets of x86
309   if (target_machine == llvm::Triple::x86 ||
310       target_machine == llvm::Triple::x86_64) {
311     m_compiler->getTargetOpts().Features.push_back("+sse");
312     m_compiler->getTargetOpts().Features.push_back("+sse2");
313   }
314 
315   // Set the target CPU to generate code for. This will be empty for any CPU
316   // that doesn't really need to make a special
317   // CPU string.
318   m_compiler->getTargetOpts().CPU = target_arch.GetClangTargetCPU();
319 
320   // Set the target ABI
321   abi = GetClangTargetABI(target_arch);
322   if (!abi.empty())
323     m_compiler->getTargetOpts().ABI = abi;
324 
325   // 3. Now allow the runtime to provide custom configuration options for the
326   // target. In this case, a specialized language runtime is available and we
327   // can query it for extra options. For 99% of use cases, this will not be
328   // needed and should be provided when basic platform detection is not enough.
329   if (lang_rt)
330     overridden_target_opts =
331         lang_rt->GetOverrideExprOptions(m_compiler->getTargetOpts());
332 
333   if (overridden_target_opts)
334     if (log && log->GetVerbose()) {
335       LLDB_LOGV(
336           log, "Using overridden target options for the expression evaluation");
337 
338       auto opts = m_compiler->getTargetOpts();
339       LLDB_LOGV(log, "Triple: '{0}'", opts.Triple);
340       LLDB_LOGV(log, "CPU: '{0}'", opts.CPU);
341       LLDB_LOGV(log, "FPMath: '{0}'", opts.FPMath);
342       LLDB_LOGV(log, "ABI: '{0}'", opts.ABI);
343       LLDB_LOGV(log, "LinkerVersion: '{0}'", opts.LinkerVersion);
344       StringList::LogDump(log, opts.FeaturesAsWritten, "FeaturesAsWritten");
345       StringList::LogDump(log, opts.Features, "Features");
346     }
347 
348   // 4. Create and install the target on the compiler.
349   m_compiler->createDiagnostics();
350   auto target_info = TargetInfo::CreateTargetInfo(
351       m_compiler->getDiagnostics(), m_compiler->getInvocation().TargetOpts);
352   if (log) {
353     log->Printf("Using SIMD alignment: %d", target_info->getSimdDefaultAlign());
354     log->Printf("Target datalayout string: '%s'",
355                 target_info->getDataLayout().getStringRepresentation().c_str());
356     log->Printf("Target ABI: '%s'", target_info->getABI().str().c_str());
357     log->Printf("Target vector alignment: %d",
358                 target_info->getMaxVectorAlign());
359   }
360   m_compiler->setTarget(target_info);
361 
362   assert(m_compiler->hasTarget());
363 
364   // 5. Set language options.
365   lldb::LanguageType language = expr.Language();
366 
367   switch (language) {
368   case lldb::eLanguageTypeC:
369   case lldb::eLanguageTypeC89:
370   case lldb::eLanguageTypeC99:
371   case lldb::eLanguageTypeC11:
372     // FIXME: the following language option is a temporary workaround,
373     // to "ask for C, get C++."
374     // For now, the expression parser must use C++ anytime the language is a C
375     // family language, because the expression parser uses features of C++ to
376     // capture values.
377     m_compiler->getLangOpts().CPlusPlus = true;
378     break;
379   case lldb::eLanguageTypeObjC:
380     m_compiler->getLangOpts().ObjC1 = true;
381     m_compiler->getLangOpts().ObjC2 = true;
382     // FIXME: the following language option is a temporary workaround,
383     // to "ask for ObjC, get ObjC++" (see comment above).
384     m_compiler->getLangOpts().CPlusPlus = true;
385 
386     // Clang now sets as default C++14 as the default standard (with
387     // GNU extensions), so we do the same here to avoid mismatches that
388     // cause compiler error when evaluating expressions (e.g. nullptr not found
389     // as it's a C++11 feature). Currently lldb evaluates C++14 as C++11 (see
390     // two lines below) so we decide to be consistent with that, but this could
391     // be re-evaluated in the future.
392     m_compiler->getLangOpts().CPlusPlus11 = true;
393     break;
394   case lldb::eLanguageTypeC_plus_plus:
395   case lldb::eLanguageTypeC_plus_plus_11:
396   case lldb::eLanguageTypeC_plus_plus_14:
397     m_compiler->getLangOpts().CPlusPlus11 = true;
398     m_compiler->getHeaderSearchOpts().UseLibcxx = true;
399     LLVM_FALLTHROUGH;
400   case lldb::eLanguageTypeC_plus_plus_03:
401     m_compiler->getLangOpts().CPlusPlus = true;
402     // FIXME: the following language option is a temporary workaround,
403     // to "ask for C++, get ObjC++".  Apple hopes to remove this requirement on
404     // non-Apple platforms, but for now it is needed.
405     m_compiler->getLangOpts().ObjC1 = true;
406     break;
407   case lldb::eLanguageTypeObjC_plus_plus:
408   case lldb::eLanguageTypeUnknown:
409   default:
410     m_compiler->getLangOpts().ObjC1 = true;
411     m_compiler->getLangOpts().ObjC2 = true;
412     m_compiler->getLangOpts().CPlusPlus = true;
413     m_compiler->getLangOpts().CPlusPlus11 = true;
414     m_compiler->getHeaderSearchOpts().UseLibcxx = true;
415     break;
416   }
417 
418   m_compiler->getLangOpts().Bool = true;
419   m_compiler->getLangOpts().WChar = true;
420   m_compiler->getLangOpts().Blocks = true;
421   m_compiler->getLangOpts().DebuggerSupport =
422       true; // Features specifically for debugger clients
423   if (expr.DesiredResultType() == Expression::eResultTypeId)
424     m_compiler->getLangOpts().DebuggerCastResultToId = true;
425 
426   m_compiler->getLangOpts().CharIsSigned =
427       ArchSpec(m_compiler->getTargetOpts().Triple.c_str())
428           .CharIsSignedByDefault();
429 
430   // Spell checking is a nice feature, but it ends up completing a lot of types
431   // that we didn't strictly speaking need to complete. As a result, we spend a
432   // long time parsing and importing debug information.
433   m_compiler->getLangOpts().SpellChecking = false;
434 
435   if (process_sp && m_compiler->getLangOpts().ObjC1) {
436     if (process_sp->GetObjCLanguageRuntime()) {
437       if (process_sp->GetObjCLanguageRuntime()->GetRuntimeVersion() ==
438           ObjCLanguageRuntime::ObjCRuntimeVersions::eAppleObjC_V2)
439         m_compiler->getLangOpts().ObjCRuntime.set(ObjCRuntime::MacOSX,
440                                                   VersionTuple(10, 7));
441       else
442         m_compiler->getLangOpts().ObjCRuntime.set(ObjCRuntime::FragileMacOSX,
443                                                   VersionTuple(10, 7));
444 
445       if (process_sp->GetObjCLanguageRuntime()->HasNewLiteralsAndIndexing())
446         m_compiler->getLangOpts().DebuggerObjCLiteral = true;
447     }
448   }
449 
450   m_compiler->getLangOpts().ThreadsafeStatics = false;
451   m_compiler->getLangOpts().AccessControl =
452       false; // Debuggers get universal access
453   m_compiler->getLangOpts().DollarIdents =
454       true; // $ indicates a persistent variable name
455 
456   // Set CodeGen options
457   m_compiler->getCodeGenOpts().EmitDeclMetadata = true;
458   m_compiler->getCodeGenOpts().InstrumentFunctions = false;
459   m_compiler->getCodeGenOpts().DisableFPElim = true;
460   m_compiler->getCodeGenOpts().OmitLeafFramePointer = false;
461   if (generate_debug_info)
462     m_compiler->getCodeGenOpts().setDebugInfo(codegenoptions::FullDebugInfo);
463   else
464     m_compiler->getCodeGenOpts().setDebugInfo(codegenoptions::NoDebugInfo);
465 
466   // Disable some warnings.
467   m_compiler->getDiagnostics().setSeverityForGroup(
468       clang::diag::Flavor::WarningOrError, "unused-value",
469       clang::diag::Severity::Ignored, SourceLocation());
470   m_compiler->getDiagnostics().setSeverityForGroup(
471       clang::diag::Flavor::WarningOrError, "odr",
472       clang::diag::Severity::Ignored, SourceLocation());
473 
474   // Inform the target of the language options
475   //
476   // FIXME: We shouldn't need to do this, the target should be immutable once
477   // created. This complexity should be lifted elsewhere.
478   m_compiler->getTarget().adjust(m_compiler->getLangOpts());
479 
480   // 6. Set up the diagnostic buffer for reporting errors
481 
482   m_compiler->getDiagnostics().setClient(new ClangDiagnosticManagerAdapter);
483 
484   // 7. Set up the source management objects inside the compiler
485 
486   clang::FileSystemOptions file_system_options;
487   m_file_manager.reset(new clang::FileManager(file_system_options));
488 
489   if (!m_compiler->hasSourceManager())
490     m_compiler->createSourceManager(*m_file_manager.get());
491 
492   m_compiler->createFileManager();
493   m_compiler->createPreprocessor(TU_Complete);
494 
495   if (ClangModulesDeclVendor *decl_vendor =
496           target_sp->GetClangModulesDeclVendor()) {
497     ClangPersistentVariables *clang_persistent_vars =
498         llvm::cast<ClangPersistentVariables>(
499             target_sp->GetPersistentExpressionStateForLanguage(
500                 lldb::eLanguageTypeC));
501     std::unique_ptr<PPCallbacks> pp_callbacks(
502         new LLDBPreprocessorCallbacks(*decl_vendor, *clang_persistent_vars));
503     m_pp_callbacks =
504         static_cast<LLDBPreprocessorCallbacks *>(pp_callbacks.get());
505     m_compiler->getPreprocessor().addPPCallbacks(std::move(pp_callbacks));
506   }
507 
508   // 8. Most of this we get from the CompilerInstance, but we also want to give
509   // the context an ExternalASTSource.
510   m_selector_table.reset(new SelectorTable());
511   m_builtin_context.reset(new Builtin::Context());
512 
513   std::unique_ptr<clang::ASTContext> ast_context(
514       new ASTContext(m_compiler->getLangOpts(), m_compiler->getSourceManager(),
515                      m_compiler->getPreprocessor().getIdentifierTable(),
516                      *m_selector_table.get(), *m_builtin_context.get()));
517 
518   ast_context->InitBuiltinTypes(m_compiler->getTarget());
519 
520   ClangExpressionHelper *type_system_helper =
521       dyn_cast<ClangExpressionHelper>(m_expr.GetTypeSystemHelper());
522   ClangExpressionDeclMap *decl_map = type_system_helper->DeclMap();
523 
524   if (decl_map) {
525     llvm::IntrusiveRefCntPtr<clang::ExternalASTSource> ast_source(
526         decl_map->CreateProxy());
527     decl_map->InstallASTContext(*ast_context, m_compiler->getFileManager());
528     ast_context->setExternalSource(ast_source);
529   }
530 
531   m_ast_context.reset(
532       new ClangASTContext(m_compiler->getTargetOpts().Triple.c_str()));
533   m_ast_context->setASTContext(ast_context.get());
534   m_compiler->setASTContext(ast_context.release());
535 
536   std::string module_name("$__lldb_module");
537 
538   m_llvm_context.reset(new LLVMContext());
539   m_code_generator.reset(CreateLLVMCodeGen(
540       m_compiler->getDiagnostics(), module_name,
541       m_compiler->getHeaderSearchOpts(), m_compiler->getPreprocessorOpts(),
542       m_compiler->getCodeGenOpts(), *m_llvm_context));
543 }
544 
545 ClangExpressionParser::~ClangExpressionParser() {}
546 
547 unsigned ClangExpressionParser::Parse(DiagnosticManager &diagnostic_manager) {
548   ClangDiagnosticManagerAdapter *adapter =
549       static_cast<ClangDiagnosticManagerAdapter *>(
550           m_compiler->getDiagnostics().getClient());
551   clang::TextDiagnosticBuffer *diag_buf = adapter->GetPassthrough();
552   diag_buf->FlushDiagnostics(m_compiler->getDiagnostics());
553 
554   adapter->ResetManager(&diagnostic_manager);
555 
556   const char *expr_text = m_expr.Text();
557 
558   clang::SourceManager &source_mgr = m_compiler->getSourceManager();
559   bool created_main_file = false;
560   if (m_compiler->getCodeGenOpts().getDebugInfo() ==
561       codegenoptions::FullDebugInfo) {
562     int temp_fd = -1;
563     llvm::SmallString<PATH_MAX> result_path;
564     if (FileSpec tmpdir_file_spec = HostInfo::GetProcessTempDir()) {
565       tmpdir_file_spec.AppendPathComponent("lldb-%%%%%%.expr");
566       std::string temp_source_path = tmpdir_file_spec.GetPath();
567       llvm::sys::fs::createUniqueFile(temp_source_path, temp_fd, result_path);
568     } else {
569       llvm::sys::fs::createTemporaryFile("lldb", "expr", temp_fd, result_path);
570     }
571 
572     if (temp_fd != -1) {
573       lldb_private::File file(temp_fd, true);
574       const size_t expr_text_len = strlen(expr_text);
575       size_t bytes_written = expr_text_len;
576       if (file.Write(expr_text, bytes_written).Success()) {
577         if (bytes_written == expr_text_len) {
578           file.Close();
579           source_mgr.setMainFileID(
580               source_mgr.createFileID(m_file_manager->getFile(result_path),
581                                       SourceLocation(), SrcMgr::C_User));
582           created_main_file = true;
583         }
584       }
585     }
586   }
587 
588   if (!created_main_file) {
589     std::unique_ptr<MemoryBuffer> memory_buffer =
590         MemoryBuffer::getMemBufferCopy(expr_text, __FUNCTION__);
591     source_mgr.setMainFileID(source_mgr.createFileID(std::move(memory_buffer)));
592   }
593 
594   diag_buf->BeginSourceFile(m_compiler->getLangOpts(),
595                             &m_compiler->getPreprocessor());
596 
597   ClangExpressionHelper *type_system_helper =
598       dyn_cast<ClangExpressionHelper>(m_expr.GetTypeSystemHelper());
599 
600   ASTConsumer *ast_transformer =
601       type_system_helper->ASTTransformer(m_code_generator.get());
602 
603   if (ClangExpressionDeclMap *decl_map = type_system_helper->DeclMap())
604     decl_map->InstallCodeGenerator(m_code_generator.get());
605 
606   if (ast_transformer) {
607     ast_transformer->Initialize(m_compiler->getASTContext());
608     ParseAST(m_compiler->getPreprocessor(), ast_transformer,
609              m_compiler->getASTContext());
610   } else {
611     m_code_generator->Initialize(m_compiler->getASTContext());
612     ParseAST(m_compiler->getPreprocessor(), m_code_generator.get(),
613              m_compiler->getASTContext());
614   }
615 
616   diag_buf->EndSourceFile();
617 
618   unsigned num_errors = diag_buf->getNumErrors();
619 
620   if (m_pp_callbacks && m_pp_callbacks->hasErrors()) {
621     num_errors++;
622     diagnostic_manager.PutString(eDiagnosticSeverityError,
623                                  "while importing modules:");
624     diagnostic_manager.AppendMessageToDiagnostic(
625         m_pp_callbacks->getErrorString());
626   }
627 
628   if (!num_errors) {
629     if (type_system_helper->DeclMap() &&
630         !type_system_helper->DeclMap()->ResolveUnknownTypes()) {
631       diagnostic_manager.Printf(eDiagnosticSeverityError,
632                                 "Couldn't infer the type of a variable");
633       num_errors++;
634     }
635   }
636 
637   if (!num_errors) {
638     type_system_helper->CommitPersistentDecls();
639   }
640 
641   adapter->ResetManager();
642 
643   return num_errors;
644 }
645 
646 std::string
647 ClangExpressionParser::GetClangTargetABI(const ArchSpec &target_arch) {
648   std::string abi;
649 
650   if (target_arch.IsMIPS()) {
651     switch (target_arch.GetFlags() & ArchSpec::eMIPSABI_mask) {
652     case ArchSpec::eMIPSABI_N64:
653       abi = "n64";
654       break;
655     case ArchSpec::eMIPSABI_N32:
656       abi = "n32";
657       break;
658     case ArchSpec::eMIPSABI_O32:
659       abi = "o32";
660       break;
661     default:
662       break;
663     }
664   }
665   return abi;
666 }
667 
668 bool ClangExpressionParser::RewriteExpression(
669     DiagnosticManager &diagnostic_manager) {
670   clang::SourceManager &source_manager = m_compiler->getSourceManager();
671   clang::edit::EditedSource editor(source_manager, m_compiler->getLangOpts(),
672                                    nullptr);
673   clang::edit::Commit commit(editor);
674   clang::Rewriter rewriter(source_manager, m_compiler->getLangOpts());
675 
676   class RewritesReceiver : public edit::EditsReceiver {
677     Rewriter &rewrite;
678 
679   public:
680     RewritesReceiver(Rewriter &in_rewrite) : rewrite(in_rewrite) {}
681 
682     void insert(SourceLocation loc, StringRef text) override {
683       rewrite.InsertText(loc, text);
684     }
685     void replace(CharSourceRange range, StringRef text) override {
686       rewrite.ReplaceText(range.getBegin(), rewrite.getRangeSize(range), text);
687     }
688   };
689 
690   RewritesReceiver rewrites_receiver(rewriter);
691 
692   const DiagnosticList &diagnostics = diagnostic_manager.Diagnostics();
693   size_t num_diags = diagnostics.size();
694   if (num_diags == 0)
695     return false;
696 
697   for (const Diagnostic *diag : diagnostic_manager.Diagnostics()) {
698     const ClangDiagnostic *diagnostic = llvm::dyn_cast<ClangDiagnostic>(diag);
699     if (diagnostic && diagnostic->HasFixIts()) {
700       for (const FixItHint &fixit : diagnostic->FixIts()) {
701         // This is cobbed from clang::Rewrite::FixItRewriter.
702         if (fixit.CodeToInsert.empty()) {
703           if (fixit.InsertFromRange.isValid()) {
704             commit.insertFromRange(fixit.RemoveRange.getBegin(),
705                                    fixit.InsertFromRange, /*afterToken=*/false,
706                                    fixit.BeforePreviousInsertions);
707           } else
708             commit.remove(fixit.RemoveRange);
709         } else {
710           if (fixit.RemoveRange.isTokenRange() ||
711               fixit.RemoveRange.getBegin() != fixit.RemoveRange.getEnd())
712             commit.replace(fixit.RemoveRange, fixit.CodeToInsert);
713           else
714             commit.insert(fixit.RemoveRange.getBegin(), fixit.CodeToInsert,
715                           /*afterToken=*/false, fixit.BeforePreviousInsertions);
716         }
717       }
718     }
719   }
720 
721   // FIXME - do we want to try to propagate specific errors here?
722   if (!commit.isCommitable())
723     return false;
724   else if (!editor.commit(commit))
725     return false;
726 
727   // Now play all the edits, and stash the result in the diagnostic manager.
728   editor.applyRewrites(rewrites_receiver);
729   RewriteBuffer &main_file_buffer =
730       rewriter.getEditBuffer(source_manager.getMainFileID());
731 
732   std::string fixed_expression;
733   llvm::raw_string_ostream out_stream(fixed_expression);
734 
735   main_file_buffer.write(out_stream);
736   out_stream.flush();
737   diagnostic_manager.SetFixedExpression(fixed_expression);
738 
739   return true;
740 }
741 
742 static bool FindFunctionInModule(ConstString &mangled_name,
743                                  llvm::Module *module, const char *orig_name) {
744   for (const auto &func : module->getFunctionList()) {
745     const StringRef &name = func.getName();
746     if (name.find(orig_name) != StringRef::npos) {
747       mangled_name.SetString(name);
748       return true;
749     }
750   }
751 
752   return false;
753 }
754 
755 lldb_private::Status ClangExpressionParser::PrepareForExecution(
756     lldb::addr_t &func_addr, lldb::addr_t &func_end,
757     lldb::IRExecutionUnitSP &execution_unit_sp, ExecutionContext &exe_ctx,
758     bool &can_interpret, ExecutionPolicy execution_policy) {
759   func_addr = LLDB_INVALID_ADDRESS;
760   func_end = LLDB_INVALID_ADDRESS;
761   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
762 
763   lldb_private::Status err;
764 
765   std::unique_ptr<llvm::Module> llvm_module_ap(
766       m_code_generator->ReleaseModule());
767 
768   if (!llvm_module_ap.get()) {
769     err.SetErrorToGenericError();
770     err.SetErrorString("IR doesn't contain a module");
771     return err;
772   }
773 
774   ConstString function_name;
775 
776   if (execution_policy != eExecutionPolicyTopLevel) {
777     // Find the actual name of the function (it's often mangled somehow)
778 
779     if (!FindFunctionInModule(function_name, llvm_module_ap.get(),
780                               m_expr.FunctionName())) {
781       err.SetErrorToGenericError();
782       err.SetErrorStringWithFormat("Couldn't find %s() in the module",
783                                    m_expr.FunctionName());
784       return err;
785     } else {
786       if (log)
787         log->Printf("Found function %s for %s", function_name.AsCString(),
788                     m_expr.FunctionName());
789     }
790   }
791 
792   SymbolContext sc;
793 
794   if (lldb::StackFrameSP frame_sp = exe_ctx.GetFrameSP()) {
795     sc = frame_sp->GetSymbolContext(lldb::eSymbolContextEverything);
796   } else if (lldb::TargetSP target_sp = exe_ctx.GetTargetSP()) {
797     sc.target_sp = target_sp;
798   }
799 
800   LLVMUserExpression::IRPasses custom_passes;
801   {
802     auto lang = m_expr.Language();
803     if (log)
804       log->Printf("%s - Current expression language is %s\n", __FUNCTION__,
805                   Language::GetNameForLanguageType(lang));
806     lldb::ProcessSP process_sp = exe_ctx.GetProcessSP();
807     if (process_sp && lang != lldb::eLanguageTypeUnknown) {
808       auto runtime = process_sp->GetLanguageRuntime(lang);
809       if (runtime)
810         runtime->GetIRPasses(custom_passes);
811     }
812   }
813 
814   if (custom_passes.EarlyPasses) {
815     if (log)
816       log->Printf("%s - Running Early IR Passes from LanguageRuntime on "
817                   "expression module '%s'",
818                   __FUNCTION__, m_expr.FunctionName());
819 
820     custom_passes.EarlyPasses->run(*llvm_module_ap);
821   }
822 
823   execution_unit_sp.reset(
824       new IRExecutionUnit(m_llvm_context, // handed off here
825                           llvm_module_ap, // handed off here
826                           function_name, exe_ctx.GetTargetSP(), sc,
827                           m_compiler->getTargetOpts().Features));
828 
829   ClangExpressionHelper *type_system_helper =
830       dyn_cast<ClangExpressionHelper>(m_expr.GetTypeSystemHelper());
831   ClangExpressionDeclMap *decl_map =
832       type_system_helper->DeclMap(); // result can be NULL
833 
834   if (decl_map) {
835     Stream *error_stream = NULL;
836     Target *target = exe_ctx.GetTargetPtr();
837     error_stream = target->GetDebugger().GetErrorFile().get();
838 
839     IRForTarget ir_for_target(decl_map, m_expr.NeedsVariableResolution(),
840                               *execution_unit_sp, *error_stream,
841                               function_name.AsCString());
842 
843     bool ir_can_run =
844         ir_for_target.runOnModule(*execution_unit_sp->GetModule());
845 
846     if (!ir_can_run) {
847       err.SetErrorString(
848           "The expression could not be prepared to run in the target");
849       return err;
850     }
851 
852     Process *process = exe_ctx.GetProcessPtr();
853 
854     if (execution_policy != eExecutionPolicyAlways &&
855         execution_policy != eExecutionPolicyTopLevel) {
856       lldb_private::Status interpret_error;
857 
858       bool interpret_function_calls =
859           !process ? false : process->CanInterpretFunctionCalls();
860       can_interpret = IRInterpreter::CanInterpret(
861           *execution_unit_sp->GetModule(), *execution_unit_sp->GetFunction(),
862           interpret_error, interpret_function_calls);
863 
864       if (!can_interpret && execution_policy == eExecutionPolicyNever) {
865         err.SetErrorStringWithFormat("Can't run the expression locally: %s",
866                                      interpret_error.AsCString());
867         return err;
868       }
869     }
870 
871     if (!process && execution_policy == eExecutionPolicyAlways) {
872       err.SetErrorString("Expression needed to run in the target, but the "
873                          "target can't be run");
874       return err;
875     }
876 
877     if (!process && execution_policy == eExecutionPolicyTopLevel) {
878       err.SetErrorString("Top-level code needs to be inserted into a runnable "
879                          "target, but the target can't be run");
880       return err;
881     }
882 
883     if (execution_policy == eExecutionPolicyAlways ||
884         (execution_policy != eExecutionPolicyTopLevel && !can_interpret)) {
885       if (m_expr.NeedsValidation() && process) {
886         if (!process->GetDynamicCheckers()) {
887           DynamicCheckerFunctions *dynamic_checkers =
888               new DynamicCheckerFunctions();
889 
890           DiagnosticManager install_diagnostics;
891 
892           if (!dynamic_checkers->Install(install_diagnostics, exe_ctx)) {
893             if (install_diagnostics.Diagnostics().size())
894               err.SetErrorString("couldn't install checkers, unknown error");
895             else
896               err.SetErrorString(install_diagnostics.GetString().c_str());
897 
898             return err;
899           }
900 
901           process->SetDynamicCheckers(dynamic_checkers);
902 
903           if (log)
904             log->Printf("== [ClangUserExpression::Evaluate] Finished "
905                         "installing dynamic checkers ==");
906         }
907 
908         IRDynamicChecks ir_dynamic_checks(*process->GetDynamicCheckers(),
909                                           function_name.AsCString());
910 
911         llvm::Module *module = execution_unit_sp->GetModule();
912         if (!module || !ir_dynamic_checks.runOnModule(*module)) {
913           err.SetErrorToGenericError();
914           err.SetErrorString("Couldn't add dynamic checks to the expression");
915           return err;
916         }
917 
918         if (custom_passes.LatePasses) {
919           if (log)
920             log->Printf("%s - Running Late IR Passes from LanguageRuntime on "
921                         "expression module '%s'",
922                         __FUNCTION__, m_expr.FunctionName());
923 
924           custom_passes.LatePasses->run(*module);
925         }
926       }
927     }
928 
929     if (execution_policy == eExecutionPolicyAlways ||
930         execution_policy == eExecutionPolicyTopLevel || !can_interpret) {
931       execution_unit_sp->GetRunnableInfo(err, func_addr, func_end);
932     }
933   } else {
934     execution_unit_sp->GetRunnableInfo(err, func_addr, func_end);
935   }
936 
937   return err;
938 }
939 
940 lldb_private::Status ClangExpressionParser::RunStaticInitializers(
941     lldb::IRExecutionUnitSP &execution_unit_sp, ExecutionContext &exe_ctx) {
942   lldb_private::Status err;
943 
944   lldbassert(execution_unit_sp.get());
945   lldbassert(exe_ctx.HasThreadScope());
946 
947   if (!execution_unit_sp.get()) {
948     err.SetErrorString(
949         "can't run static initializers for a NULL execution unit");
950     return err;
951   }
952 
953   if (!exe_ctx.HasThreadScope()) {
954     err.SetErrorString("can't run static initializers without a thread");
955     return err;
956   }
957 
958   std::vector<lldb::addr_t> static_initializers;
959 
960   execution_unit_sp->GetStaticInitializers(static_initializers);
961 
962   for (lldb::addr_t static_initializer : static_initializers) {
963     EvaluateExpressionOptions options;
964 
965     lldb::ThreadPlanSP call_static_initializer(new ThreadPlanCallFunction(
966         exe_ctx.GetThreadRef(), Address(static_initializer), CompilerType(),
967         llvm::ArrayRef<lldb::addr_t>(), options));
968 
969     DiagnosticManager execution_errors;
970     lldb::ExpressionResults results =
971         exe_ctx.GetThreadRef().GetProcess()->RunThreadPlan(
972             exe_ctx, call_static_initializer, options, execution_errors);
973 
974     if (results != lldb::eExpressionCompleted) {
975       err.SetErrorStringWithFormat("couldn't run static initializer: %s",
976                                    execution_errors.GetString().c_str());
977       return err;
978     }
979   }
980 
981   return err;
982 }
983