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
186         // context in an expression for the warning to be useful.
187         // FIXME: Should we try to filter out FixIts that apply to our generated
188         // code, and not the user's expression?
189         if (severity == eDiagnosticSeverityError) {
190           size_t num_fixit_hints = Info.getNumFixItHints();
191           for (size_t i = 0; i < num_fixit_hints; i++) {
192             const clang::FixItHint &fixit = Info.getFixItHint(i);
193             if (!fixit.isNull())
194               new_diagnostic->AddFixitHint(fixit);
195           }
196         }
197       }
198     }
199 
200     m_passthrough->HandleDiagnostic(DiagLevel, Info);
201   }
202 
203   void FlushDiagnostics(DiagnosticsEngine &Diags) {
204     m_passthrough->FlushDiagnostics(Diags);
205   }
206 
207   DiagnosticConsumer *clone(DiagnosticsEngine &Diags) const {
208     return new ClangDiagnosticManagerAdapter(m_passthrough);
209   }
210 
211   clang::TextDiagnosticBuffer *GetPassthrough() { return m_passthrough.get(); }
212 
213 private:
214   DiagnosticManager *m_manager = nullptr;
215   std::shared_ptr<clang::TextDiagnosticBuffer> m_passthrough;
216 };
217 
218 //===----------------------------------------------------------------------===//
219 // Implementation of ClangExpressionParser
220 //===----------------------------------------------------------------------===//
221 
222 ClangExpressionParser::ClangExpressionParser(ExecutionContextScope *exe_scope,
223                                              Expression &expr,
224                                              bool generate_debug_info)
225     : ExpressionParser(exe_scope, expr, generate_debug_info), m_compiler(),
226       m_code_generator(), m_pp_callbacks(nullptr) {
227   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
228 
229   // We can't compile expressions without a target.  So if the exe_scope is null
230   // or doesn't have a target,
231   // then we just need to get out of here.  I'll lldb_assert and not make any of
232   // the compiler objects since
233   // I can't return errors directly from the constructor.  Further calls will
234   // check if the compiler was made and
235   // bag out if it wasn't.
236 
237   if (!exe_scope) {
238     lldb_assert(exe_scope, "Can't make an expression parser with a null scope.",
239                 __FUNCTION__, __FILE__, __LINE__);
240     return;
241   }
242 
243   lldb::TargetSP target_sp;
244   target_sp = exe_scope->CalculateTarget();
245   if (!target_sp) {
246     lldb_assert(target_sp.get(),
247                 "Can't make an expression parser with a null target.",
248                 __FUNCTION__, __FILE__, __LINE__);
249     return;
250   }
251 
252   // 1. Create a new compiler instance.
253   m_compiler.reset(new CompilerInstance());
254   lldb::LanguageType frame_lang =
255       expr.Language(); // defaults to lldb::eLanguageTypeUnknown
256   bool overridden_target_opts = false;
257   lldb_private::LanguageRuntime *lang_rt = nullptr;
258 
259   std::string abi;
260   ArchSpec target_arch;
261   target_arch = target_sp->GetArchitecture();
262 
263   const auto target_machine = target_arch.GetMachine();
264 
265   // If the expression is being evaluated in the context of an existing
266   // stack frame, we introspect to see if the language runtime is available.
267 
268   lldb::StackFrameSP frame_sp = exe_scope->CalculateStackFrame();
269   lldb::ProcessSP process_sp = exe_scope->CalculateProcess();
270 
271   // Make sure the user hasn't provided a preferred execution language
272   // with `expression --language X -- ...`
273   if (frame_sp && frame_lang == lldb::eLanguageTypeUnknown)
274     frame_lang = frame_sp->GetLanguage();
275 
276   if (process_sp && frame_lang != lldb::eLanguageTypeUnknown) {
277     lang_rt = process_sp->GetLanguageRuntime(frame_lang);
278     if (log)
279       log->Printf("Frame has language of type %s",
280                   Language::GetNameForLanguageType(frame_lang));
281   }
282 
283   // 2. Configure the compiler with a set of default options that are
284   // appropriate
285   // for most situations.
286   if (target_arch.IsValid()) {
287     std::string triple = target_arch.GetTriple().str();
288     m_compiler->getTargetOpts().Triple = triple;
289     if (log)
290       log->Printf("Using %s as the target triple",
291                   m_compiler->getTargetOpts().Triple.c_str());
292   } else {
293     // If we get here we don't have a valid target and just have to guess.
294     // Sometimes this will be ok to just use the host target triple (when we
295     // evaluate say "2+3", but other
296     // expressions like breakpoint conditions and other things that _are_ target
297     // specific really shouldn't just be
298     // using the host triple. In such a case the language runtime should expose
299     // an overridden options set (3),
300     // below.
301     m_compiler->getTargetOpts().Triple = llvm::sys::getDefaultTargetTriple();
302     if (log)
303       log->Printf("Using default target triple of %s",
304                   m_compiler->getTargetOpts().Triple.c_str());
305   }
306   // Now add some special fixes for known architectures:
307   // Any arm32 iOS environment, but not on arm64
308   if (m_compiler->getTargetOpts().Triple.find("arm64") == std::string::npos &&
309       m_compiler->getTargetOpts().Triple.find("arm") != std::string::npos &&
310       m_compiler->getTargetOpts().Triple.find("ios") != std::string::npos) {
311     m_compiler->getTargetOpts().ABI = "apcs-gnu";
312   }
313   // Supported subsets of x86
314   if (target_machine == llvm::Triple::x86 ||
315       target_machine == llvm::Triple::x86_64) {
316     m_compiler->getTargetOpts().Features.push_back("+sse");
317     m_compiler->getTargetOpts().Features.push_back("+sse2");
318   }
319 
320   // Set the target CPU to generate code for.
321   // This will be empty for any CPU that doesn't really need to make a special
322   // CPU string.
323   m_compiler->getTargetOpts().CPU = target_arch.GetClangTargetCPU();
324 
325   // Set the target ABI
326   abi = GetClangTargetABI(target_arch);
327   if (!abi.empty())
328     m_compiler->getTargetOpts().ABI = abi;
329 
330   // 3. Now allow the runtime to provide custom configuration options for the
331   // target.
332   // In this case, a specialized language runtime is available and we can query
333   // it for extra options.
334   // For 99% of use cases, this will not be needed and should be provided when
335   // basic platform detection is not enough.
336   if (lang_rt)
337     overridden_target_opts =
338         lang_rt->GetOverrideExprOptions(m_compiler->getTargetOpts());
339 
340   if (overridden_target_opts)
341     if (log && log->GetVerbose()) {
342       LLDB_LOGV(
343           log, "Using overridden target options for the expression evaluation");
344 
345       auto opts = m_compiler->getTargetOpts();
346       LLDB_LOGV(log, "Triple: '{0}'", opts.Triple);
347       LLDB_LOGV(log, "CPU: '{0}'", opts.CPU);
348       LLDB_LOGV(log, "FPMath: '{0}'", opts.FPMath);
349       LLDB_LOGV(log, "ABI: '{0}'", opts.ABI);
350       LLDB_LOGV(log, "LinkerVersion: '{0}'", opts.LinkerVersion);
351       StringList::LogDump(log, opts.FeaturesAsWritten, "FeaturesAsWritten");
352       StringList::LogDump(log, opts.Features, "Features");
353     }
354 
355   // 4. Create and install the target on the compiler.
356   m_compiler->createDiagnostics();
357   auto target_info = TargetInfo::CreateTargetInfo(
358       m_compiler->getDiagnostics(), m_compiler->getInvocation().TargetOpts);
359   if (log) {
360     log->Printf("Using SIMD alignment: %d", target_info->getSimdDefaultAlign());
361     log->Printf("Target datalayout string: '%s'",
362                 target_info->getDataLayout().getStringRepresentation().c_str());
363     log->Printf("Target ABI: '%s'", target_info->getABI().str().c_str());
364     log->Printf("Target vector alignment: %d",
365                 target_info->getMaxVectorAlign());
366   }
367   m_compiler->setTarget(target_info);
368 
369   assert(m_compiler->hasTarget());
370 
371   // 5. Set language options.
372   lldb::LanguageType language = expr.Language();
373 
374   switch (language) {
375   case lldb::eLanguageTypeC:
376   case lldb::eLanguageTypeC89:
377   case lldb::eLanguageTypeC99:
378   case lldb::eLanguageTypeC11:
379     // FIXME: the following language option is a temporary workaround,
380     // to "ask for C, get C++."
381     // For now, the expression parser must use C++ anytime the
382     // language is a C family language, because the expression parser
383     // uses features of C++ to capture values.
384     m_compiler->getLangOpts().CPlusPlus = true;
385     break;
386   case lldb::eLanguageTypeObjC:
387     m_compiler->getLangOpts().ObjC1 = true;
388     m_compiler->getLangOpts().ObjC2 = true;
389     // FIXME: the following language option is a temporary workaround,
390     // to "ask for ObjC, get ObjC++" (see comment above).
391     m_compiler->getLangOpts().CPlusPlus = true;
392 
393     // Clang now sets as default C++14 as the default standard (with
394     // GNU extensions), so we do the same here to avoid mismatches that
395     // cause compiler error when evaluating expressions (e.g. nullptr
396     // not found as it's a C++11 feature). Currently lldb evaluates
397     // C++14 as C++11 (see two lines below) so we decide to be consistent
398     // with that, but this could be re-evaluated in the future.
399     m_compiler->getLangOpts().CPlusPlus11 = true;
400     break;
401   case lldb::eLanguageTypeC_plus_plus:
402   case lldb::eLanguageTypeC_plus_plus_11:
403   case lldb::eLanguageTypeC_plus_plus_14:
404     m_compiler->getLangOpts().CPlusPlus11 = true;
405     m_compiler->getHeaderSearchOpts().UseLibcxx = true;
406     LLVM_FALLTHROUGH;
407   case lldb::eLanguageTypeC_plus_plus_03:
408     m_compiler->getLangOpts().CPlusPlus = true;
409     // FIXME: the following language option is a temporary workaround,
410     // to "ask for C++, get ObjC++".  Apple hopes to remove this requirement
411     // on non-Apple platforms, but for now it is needed.
412     m_compiler->getLangOpts().ObjC1 = true;
413     break;
414   case lldb::eLanguageTypeObjC_plus_plus:
415   case lldb::eLanguageTypeUnknown:
416   default:
417     m_compiler->getLangOpts().ObjC1 = true;
418     m_compiler->getLangOpts().ObjC2 = true;
419     m_compiler->getLangOpts().CPlusPlus = true;
420     m_compiler->getLangOpts().CPlusPlus11 = true;
421     m_compiler->getHeaderSearchOpts().UseLibcxx = true;
422     break;
423   }
424 
425   m_compiler->getLangOpts().Bool = true;
426   m_compiler->getLangOpts().WChar = true;
427   m_compiler->getLangOpts().Blocks = true;
428   m_compiler->getLangOpts().DebuggerSupport =
429       true; // Features specifically for debugger clients
430   if (expr.DesiredResultType() == Expression::eResultTypeId)
431     m_compiler->getLangOpts().DebuggerCastResultToId = true;
432 
433   m_compiler->getLangOpts().CharIsSigned =
434       ArchSpec(m_compiler->getTargetOpts().Triple.c_str())
435           .CharIsSignedByDefault();
436 
437   // Spell checking is a nice feature, but it ends up completing a
438   // lot of types that we didn't strictly speaking need to complete.
439   // As a result, we spend a long time parsing and importing debug
440   // information.
441   m_compiler->getLangOpts().SpellChecking = false;
442 
443   if (process_sp && m_compiler->getLangOpts().ObjC1) {
444     if (process_sp->GetObjCLanguageRuntime()) {
445       if (process_sp->GetObjCLanguageRuntime()->GetRuntimeVersion() ==
446           ObjCLanguageRuntime::ObjCRuntimeVersions::eAppleObjC_V2)
447         m_compiler->getLangOpts().ObjCRuntime.set(ObjCRuntime::MacOSX,
448                                                   VersionTuple(10, 7));
449       else
450         m_compiler->getLangOpts().ObjCRuntime.set(ObjCRuntime::FragileMacOSX,
451                                                   VersionTuple(10, 7));
452 
453       if (process_sp->GetObjCLanguageRuntime()->HasNewLiteralsAndIndexing())
454         m_compiler->getLangOpts().DebuggerObjCLiteral = true;
455     }
456   }
457 
458   m_compiler->getLangOpts().ThreadsafeStatics = false;
459   m_compiler->getLangOpts().AccessControl =
460       false; // Debuggers get universal access
461   m_compiler->getLangOpts().DollarIdents =
462       true; // $ indicates a persistent variable name
463 
464   // Set CodeGen options
465   m_compiler->getCodeGenOpts().EmitDeclMetadata = true;
466   m_compiler->getCodeGenOpts().InstrumentFunctions = false;
467   m_compiler->getCodeGenOpts().DisableFPElim = true;
468   m_compiler->getCodeGenOpts().OmitLeafFramePointer = false;
469   if (generate_debug_info)
470     m_compiler->getCodeGenOpts().setDebugInfo(codegenoptions::FullDebugInfo);
471   else
472     m_compiler->getCodeGenOpts().setDebugInfo(codegenoptions::NoDebugInfo);
473 
474   // Disable some warnings.
475   m_compiler->getDiagnostics().setSeverityForGroup(
476       clang::diag::Flavor::WarningOrError, "unused-value",
477       clang::diag::Severity::Ignored, SourceLocation());
478   m_compiler->getDiagnostics().setSeverityForGroup(
479       clang::diag::Flavor::WarningOrError, "odr",
480       clang::diag::Severity::Ignored, SourceLocation());
481 
482   // Inform the target of the language options
483   //
484   // FIXME: We shouldn't need to do this, the target should be immutable once
485   // created. This complexity should be lifted elsewhere.
486   m_compiler->getTarget().adjust(m_compiler->getLangOpts());
487 
488   // 6. Set up the diagnostic buffer for reporting errors
489 
490   m_compiler->getDiagnostics().setClient(new ClangDiagnosticManagerAdapter);
491 
492   // 7. Set up the source management objects inside the compiler
493 
494   clang::FileSystemOptions file_system_options;
495   m_file_manager.reset(new clang::FileManager(file_system_options));
496 
497   if (!m_compiler->hasSourceManager())
498     m_compiler->createSourceManager(*m_file_manager.get());
499 
500   m_compiler->createFileManager();
501   m_compiler->createPreprocessor(TU_Complete);
502 
503   if (ClangModulesDeclVendor *decl_vendor =
504           target_sp->GetClangModulesDeclVendor()) {
505     ClangPersistentVariables *clang_persistent_vars =
506         llvm::cast<ClangPersistentVariables>(
507             target_sp->GetPersistentExpressionStateForLanguage(
508                 lldb::eLanguageTypeC));
509     std::unique_ptr<PPCallbacks> pp_callbacks(
510         new LLDBPreprocessorCallbacks(*decl_vendor, *clang_persistent_vars));
511     m_pp_callbacks =
512         static_cast<LLDBPreprocessorCallbacks *>(pp_callbacks.get());
513     m_compiler->getPreprocessor().addPPCallbacks(std::move(pp_callbacks));
514   }
515 
516   // 8. Most of this we get from the CompilerInstance, but we
517   // also want to give the context an ExternalASTSource.
518   m_selector_table.reset(new SelectorTable());
519   m_builtin_context.reset(new Builtin::Context());
520 
521   std::unique_ptr<clang::ASTContext> ast_context(
522       new ASTContext(m_compiler->getLangOpts(), m_compiler->getSourceManager(),
523                      m_compiler->getPreprocessor().getIdentifierTable(),
524                      *m_selector_table.get(), *m_builtin_context.get()));
525 
526   ast_context->InitBuiltinTypes(m_compiler->getTarget());
527 
528   ClangExpressionHelper *type_system_helper =
529       dyn_cast<ClangExpressionHelper>(m_expr.GetTypeSystemHelper());
530   ClangExpressionDeclMap *decl_map = type_system_helper->DeclMap();
531 
532   if (decl_map) {
533     llvm::IntrusiveRefCntPtr<clang::ExternalASTSource> ast_source(
534         decl_map->CreateProxy());
535     decl_map->InstallASTContext(*ast_context, m_compiler->getFileManager());
536     ast_context->setExternalSource(ast_source);
537   }
538 
539   m_ast_context.reset(
540       new ClangASTContext(m_compiler->getTargetOpts().Triple.c_str()));
541   m_ast_context->setASTContext(ast_context.get());
542   m_compiler->setASTContext(ast_context.release());
543 
544   std::string module_name("$__lldb_module");
545 
546   m_llvm_context.reset(new LLVMContext());
547   m_code_generator.reset(CreateLLVMCodeGen(
548       m_compiler->getDiagnostics(), module_name,
549       m_compiler->getHeaderSearchOpts(), m_compiler->getPreprocessorOpts(),
550       m_compiler->getCodeGenOpts(), *m_llvm_context));
551 }
552 
553 ClangExpressionParser::~ClangExpressionParser() {}
554 
555 unsigned ClangExpressionParser::Parse(DiagnosticManager &diagnostic_manager) {
556   ClangDiagnosticManagerAdapter *adapter =
557       static_cast<ClangDiagnosticManagerAdapter *>(
558           m_compiler->getDiagnostics().getClient());
559   clang::TextDiagnosticBuffer *diag_buf = adapter->GetPassthrough();
560   diag_buf->FlushDiagnostics(m_compiler->getDiagnostics());
561 
562   adapter->ResetManager(&diagnostic_manager);
563 
564   const char *expr_text = m_expr.Text();
565 
566   clang::SourceManager &source_mgr = m_compiler->getSourceManager();
567   bool created_main_file = false;
568   if (m_compiler->getCodeGenOpts().getDebugInfo() ==
569       codegenoptions::FullDebugInfo) {
570     int temp_fd = -1;
571     llvm::SmallString<PATH_MAX> result_path;
572     FileSpec tmpdir_file_spec;
573     if (HostInfo::GetLLDBPath(lldb::ePathTypeLLDBTempSystemDir,
574                               tmpdir_file_spec)) {
575       tmpdir_file_spec.AppendPathComponent("lldb-%%%%%%.expr");
576       std::string temp_source_path = tmpdir_file_spec.GetPath();
577       llvm::sys::fs::createUniqueFile(temp_source_path, temp_fd, result_path);
578     } else {
579       llvm::sys::fs::createTemporaryFile("lldb", "expr", temp_fd, result_path);
580     }
581 
582     if (temp_fd != -1) {
583       lldb_private::File file(temp_fd, true);
584       const size_t expr_text_len = strlen(expr_text);
585       size_t bytes_written = expr_text_len;
586       if (file.Write(expr_text, bytes_written).Success()) {
587         if (bytes_written == expr_text_len) {
588           file.Close();
589           source_mgr.setMainFileID(
590               source_mgr.createFileID(m_file_manager->getFile(result_path),
591                                       SourceLocation(), SrcMgr::C_User));
592           created_main_file = true;
593         }
594       }
595     }
596   }
597 
598   if (!created_main_file) {
599     std::unique_ptr<MemoryBuffer> memory_buffer =
600         MemoryBuffer::getMemBufferCopy(expr_text, __FUNCTION__);
601     source_mgr.setMainFileID(source_mgr.createFileID(std::move(memory_buffer)));
602   }
603 
604   diag_buf->BeginSourceFile(m_compiler->getLangOpts(),
605                             &m_compiler->getPreprocessor());
606 
607   ClangExpressionHelper *type_system_helper =
608       dyn_cast<ClangExpressionHelper>(m_expr.GetTypeSystemHelper());
609 
610   ASTConsumer *ast_transformer =
611       type_system_helper->ASTTransformer(m_code_generator.get());
612 
613   if (ClangExpressionDeclMap *decl_map = type_system_helper->DeclMap())
614     decl_map->InstallCodeGenerator(m_code_generator.get());
615 
616   if (ast_transformer) {
617     ast_transformer->Initialize(m_compiler->getASTContext());
618     ParseAST(m_compiler->getPreprocessor(), ast_transformer,
619              m_compiler->getASTContext());
620   } else {
621     m_code_generator->Initialize(m_compiler->getASTContext());
622     ParseAST(m_compiler->getPreprocessor(), m_code_generator.get(),
623              m_compiler->getASTContext());
624   }
625 
626   diag_buf->EndSourceFile();
627 
628   unsigned num_errors = diag_buf->getNumErrors();
629 
630   if (m_pp_callbacks && m_pp_callbacks->hasErrors()) {
631     num_errors++;
632     diagnostic_manager.PutString(eDiagnosticSeverityError,
633                                  "while importing modules:");
634     diagnostic_manager.AppendMessageToDiagnostic(
635         m_pp_callbacks->getErrorString());
636   }
637 
638   if (!num_errors) {
639     if (type_system_helper->DeclMap() &&
640         !type_system_helper->DeclMap()->ResolveUnknownTypes()) {
641       diagnostic_manager.Printf(eDiagnosticSeverityError,
642                                 "Couldn't infer the type of a variable");
643       num_errors++;
644     }
645   }
646 
647   if (!num_errors) {
648     type_system_helper->CommitPersistentDecls();
649   }
650 
651   adapter->ResetManager();
652 
653   return num_errors;
654 }
655 
656 std::string
657 ClangExpressionParser::GetClangTargetABI(const ArchSpec &target_arch) {
658   std::string abi;
659 
660   if (target_arch.IsMIPS()) {
661     switch (target_arch.GetFlags() & ArchSpec::eMIPSABI_mask) {
662     case ArchSpec::eMIPSABI_N64:
663       abi = "n64";
664       break;
665     case ArchSpec::eMIPSABI_N32:
666       abi = "n32";
667       break;
668     case ArchSpec::eMIPSABI_O32:
669       abi = "o32";
670       break;
671     default:
672       break;
673     }
674   }
675   return abi;
676 }
677 
678 bool ClangExpressionParser::RewriteExpression(
679     DiagnosticManager &diagnostic_manager) {
680   clang::SourceManager &source_manager = m_compiler->getSourceManager();
681   clang::edit::EditedSource editor(source_manager, m_compiler->getLangOpts(),
682                                    nullptr);
683   clang::edit::Commit commit(editor);
684   clang::Rewriter rewriter(source_manager, m_compiler->getLangOpts());
685 
686   class RewritesReceiver : public edit::EditsReceiver {
687     Rewriter &rewrite;
688 
689   public:
690     RewritesReceiver(Rewriter &in_rewrite) : rewrite(in_rewrite) {}
691 
692     void insert(SourceLocation loc, StringRef text) override {
693       rewrite.InsertText(loc, text);
694     }
695     void replace(CharSourceRange range, StringRef text) override {
696       rewrite.ReplaceText(range.getBegin(), rewrite.getRangeSize(range), text);
697     }
698   };
699 
700   RewritesReceiver rewrites_receiver(rewriter);
701 
702   const DiagnosticList &diagnostics = diagnostic_manager.Diagnostics();
703   size_t num_diags = diagnostics.size();
704   if (num_diags == 0)
705     return false;
706 
707   for (const Diagnostic *diag : diagnostic_manager.Diagnostics()) {
708     const ClangDiagnostic *diagnostic = llvm::dyn_cast<ClangDiagnostic>(diag);
709     if (diagnostic && diagnostic->HasFixIts()) {
710       for (const FixItHint &fixit : diagnostic->FixIts()) {
711         // This is cobbed from clang::Rewrite::FixItRewriter.
712         if (fixit.CodeToInsert.empty()) {
713           if (fixit.InsertFromRange.isValid()) {
714             commit.insertFromRange(fixit.RemoveRange.getBegin(),
715                                    fixit.InsertFromRange, /*afterToken=*/false,
716                                    fixit.BeforePreviousInsertions);
717           } else
718             commit.remove(fixit.RemoveRange);
719         } else {
720           if (fixit.RemoveRange.isTokenRange() ||
721               fixit.RemoveRange.getBegin() != fixit.RemoveRange.getEnd())
722             commit.replace(fixit.RemoveRange, fixit.CodeToInsert);
723           else
724             commit.insert(fixit.RemoveRange.getBegin(), fixit.CodeToInsert,
725                           /*afterToken=*/false, fixit.BeforePreviousInsertions);
726         }
727       }
728     }
729   }
730 
731   // FIXME - do we want to try to propagate specific errors here?
732   if (!commit.isCommitable())
733     return false;
734   else if (!editor.commit(commit))
735     return false;
736 
737   // Now play all the edits, and stash the result in the diagnostic manager.
738   editor.applyRewrites(rewrites_receiver);
739   RewriteBuffer &main_file_buffer =
740       rewriter.getEditBuffer(source_manager.getMainFileID());
741 
742   std::string fixed_expression;
743   llvm::raw_string_ostream out_stream(fixed_expression);
744 
745   main_file_buffer.write(out_stream);
746   out_stream.flush();
747   diagnostic_manager.SetFixedExpression(fixed_expression);
748 
749   return true;
750 }
751 
752 static bool FindFunctionInModule(ConstString &mangled_name,
753                                  llvm::Module *module, const char *orig_name) {
754   for (const auto &func : module->getFunctionList()) {
755     const StringRef &name = func.getName();
756     if (name.find(orig_name) != StringRef::npos) {
757       mangled_name.SetString(name);
758       return true;
759     }
760   }
761 
762   return false;
763 }
764 
765 lldb_private::Status ClangExpressionParser::PrepareForExecution(
766     lldb::addr_t &func_addr, lldb::addr_t &func_end,
767     lldb::IRExecutionUnitSP &execution_unit_sp, ExecutionContext &exe_ctx,
768     bool &can_interpret, ExecutionPolicy execution_policy) {
769   func_addr = LLDB_INVALID_ADDRESS;
770   func_end = LLDB_INVALID_ADDRESS;
771   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
772 
773   lldb_private::Status err;
774 
775   std::unique_ptr<llvm::Module> llvm_module_ap(
776       m_code_generator->ReleaseModule());
777 
778   if (!llvm_module_ap.get()) {
779     err.SetErrorToGenericError();
780     err.SetErrorString("IR doesn't contain a module");
781     return err;
782   }
783 
784   ConstString function_name;
785 
786   if (execution_policy != eExecutionPolicyTopLevel) {
787     // Find the actual name of the function (it's often mangled somehow)
788 
789     if (!FindFunctionInModule(function_name, llvm_module_ap.get(),
790                               m_expr.FunctionName())) {
791       err.SetErrorToGenericError();
792       err.SetErrorStringWithFormat("Couldn't find %s() in the module",
793                                    m_expr.FunctionName());
794       return err;
795     } else {
796       if (log)
797         log->Printf("Found function %s for %s", function_name.AsCString(),
798                     m_expr.FunctionName());
799     }
800   }
801 
802   SymbolContext sc;
803 
804   if (lldb::StackFrameSP frame_sp = exe_ctx.GetFrameSP()) {
805     sc = frame_sp->GetSymbolContext(lldb::eSymbolContextEverything);
806   } else if (lldb::TargetSP target_sp = exe_ctx.GetTargetSP()) {
807     sc.target_sp = target_sp;
808   }
809 
810   LLVMUserExpression::IRPasses custom_passes;
811   {
812     auto lang = m_expr.Language();
813     if (log)
814       log->Printf("%s - Currrent expression language is %s\n", __FUNCTION__,
815                   Language::GetNameForLanguageType(lang));
816     lldb::ProcessSP process_sp = exe_ctx.GetProcessSP();
817     if (process_sp && lang != lldb::eLanguageTypeUnknown) {
818       auto runtime = process_sp->GetLanguageRuntime(lang);
819       if (runtime)
820         runtime->GetIRPasses(custom_passes);
821     }
822   }
823 
824   if (custom_passes.EarlyPasses) {
825     if (log)
826       log->Printf("%s - Running Early IR Passes from LanguageRuntime on "
827                   "expression module '%s'",
828                   __FUNCTION__, m_expr.FunctionName());
829 
830     custom_passes.EarlyPasses->run(*llvm_module_ap);
831   }
832 
833   execution_unit_sp.reset(
834       new IRExecutionUnit(m_llvm_context, // handed off here
835                           llvm_module_ap, // handed off here
836                           function_name, exe_ctx.GetTargetSP(), sc,
837                           m_compiler->getTargetOpts().Features));
838 
839   ClangExpressionHelper *type_system_helper =
840       dyn_cast<ClangExpressionHelper>(m_expr.GetTypeSystemHelper());
841   ClangExpressionDeclMap *decl_map =
842       type_system_helper->DeclMap(); // result can be NULL
843 
844   if (decl_map) {
845     Stream *error_stream = NULL;
846     Target *target = exe_ctx.GetTargetPtr();
847     error_stream = target->GetDebugger().GetErrorFile().get();
848 
849     IRForTarget ir_for_target(decl_map, m_expr.NeedsVariableResolution(),
850                               *execution_unit_sp, *error_stream,
851                               function_name.AsCString());
852 
853     bool ir_can_run =
854         ir_for_target.runOnModule(*execution_unit_sp->GetModule());
855 
856     if (!ir_can_run) {
857       err.SetErrorString(
858           "The expression could not be prepared to run in the target");
859       return err;
860     }
861 
862     Process *process = exe_ctx.GetProcessPtr();
863 
864     if (execution_policy != eExecutionPolicyAlways &&
865         execution_policy != eExecutionPolicyTopLevel) {
866       lldb_private::Status interpret_error;
867 
868       bool interpret_function_calls =
869           !process ? false : process->CanInterpretFunctionCalls();
870       can_interpret = IRInterpreter::CanInterpret(
871           *execution_unit_sp->GetModule(), *execution_unit_sp->GetFunction(),
872           interpret_error, interpret_function_calls);
873 
874       if (!can_interpret && execution_policy == eExecutionPolicyNever) {
875         err.SetErrorStringWithFormat("Can't run the expression locally: %s",
876                                      interpret_error.AsCString());
877         return err;
878       }
879     }
880 
881     if (!process && execution_policy == eExecutionPolicyAlways) {
882       err.SetErrorString("Expression needed to run in the target, but the "
883                          "target can't be run");
884       return err;
885     }
886 
887     if (!process && execution_policy == eExecutionPolicyTopLevel) {
888       err.SetErrorString("Top-level code needs to be inserted into a runnable "
889                          "target, but the target can't be run");
890       return err;
891     }
892 
893     if (execution_policy == eExecutionPolicyAlways ||
894         (execution_policy != eExecutionPolicyTopLevel && !can_interpret)) {
895       if (m_expr.NeedsValidation() && process) {
896         if (!process->GetDynamicCheckers()) {
897           DynamicCheckerFunctions *dynamic_checkers =
898               new DynamicCheckerFunctions();
899 
900           DiagnosticManager install_diagnostics;
901 
902           if (!dynamic_checkers->Install(install_diagnostics, exe_ctx)) {
903             if (install_diagnostics.Diagnostics().size())
904               err.SetErrorString("couldn't install checkers, unknown error");
905             else
906               err.SetErrorString(install_diagnostics.GetString().c_str());
907 
908             return err;
909           }
910 
911           process->SetDynamicCheckers(dynamic_checkers);
912 
913           if (log)
914             log->Printf("== [ClangUserExpression::Evaluate] Finished "
915                         "installing dynamic checkers ==");
916         }
917 
918         IRDynamicChecks ir_dynamic_checks(*process->GetDynamicCheckers(),
919                                           function_name.AsCString());
920 
921         llvm::Module *module = execution_unit_sp->GetModule();
922         if (!module || !ir_dynamic_checks.runOnModule(*module)) {
923           err.SetErrorToGenericError();
924           err.SetErrorString("Couldn't add dynamic checks to the expression");
925           return err;
926         }
927 
928         if (custom_passes.LatePasses) {
929           if (log)
930             log->Printf("%s - Running Late IR Passes from LanguageRuntime on "
931                         "expression module '%s'",
932                         __FUNCTION__, m_expr.FunctionName());
933 
934           custom_passes.LatePasses->run(*module);
935         }
936       }
937     }
938 
939     if (execution_policy == eExecutionPolicyAlways ||
940         execution_policy == eExecutionPolicyTopLevel || !can_interpret) {
941       execution_unit_sp->GetRunnableInfo(err, func_addr, func_end);
942     }
943   } else {
944     execution_unit_sp->GetRunnableInfo(err, func_addr, func_end);
945   }
946 
947   return err;
948 }
949 
950 lldb_private::Status ClangExpressionParser::RunStaticInitializers(
951     lldb::IRExecutionUnitSP &execution_unit_sp, ExecutionContext &exe_ctx) {
952   lldb_private::Status err;
953 
954   lldbassert(execution_unit_sp.get());
955   lldbassert(exe_ctx.HasThreadScope());
956 
957   if (!execution_unit_sp.get()) {
958     err.SetErrorString(
959         "can't run static initializers for a NULL execution unit");
960     return err;
961   }
962 
963   if (!exe_ctx.HasThreadScope()) {
964     err.SetErrorString("can't run static initializers without a thread");
965     return err;
966   }
967 
968   std::vector<lldb::addr_t> static_initializers;
969 
970   execution_unit_sp->GetStaticInitializers(static_initializers);
971 
972   for (lldb::addr_t static_initializer : static_initializers) {
973     EvaluateExpressionOptions options;
974 
975     lldb::ThreadPlanSP call_static_initializer(new ThreadPlanCallFunction(
976         exe_ctx.GetThreadRef(), Address(static_initializer), CompilerType(),
977         llvm::ArrayRef<lldb::addr_t>(), options));
978 
979     DiagnosticManager execution_errors;
980     lldb::ExpressionResults results =
981         exe_ctx.GetThreadRef().GetProcess()->RunThreadPlan(
982             exe_ctx, call_static_initializer, options, execution_errors);
983 
984     if (results != lldb::eExpressionCompleted) {
985       err.SetErrorStringWithFormat("couldn't run static initializer: %s",
986                                    execution_errors.GetString().c_str());
987       return err;
988     }
989   }
990 
991   return err;
992 }
993