1	//===-- ClangExpressionParser.cpp -----------------------------------------===//
2	//
3	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4	// See https://llvm.org/LICENSE.txt for license information.
5	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6	//
7	//===----------------------------------------------------------------------===//
8
9	#include "clang/AST/ASTContext.h"
10	#include "clang/AST/ASTDiagnostic.h"
11	#include "clang/AST/ExternalASTSource.h"
12	#include "clang/AST/PrettyPrinter.h"
13	#include "clang/Basic/Builtins.h"
14	#include "clang/Basic/DiagnosticIDs.h"
15	#include "clang/Basic/SourceLocation.h"
16	#include "clang/Basic/TargetInfo.h"
17	#include "clang/Basic/Version.h"
18	#include "clang/CodeGen/CodeGenAction.h"
19	#include "clang/CodeGen/ModuleBuilder.h"
20	#include "clang/Edit/Commit.h"
21	#include "clang/Edit/EditedSource.h"
22	#include "clang/Edit/EditsReceiver.h"
23	#include "clang/Frontend/CompilerInstance.h"
24	#include "clang/Frontend/CompilerInvocation.h"
25	#include "clang/Frontend/FrontendActions.h"
26	#include "clang/Frontend/FrontendDiagnostic.h"
27	#include "clang/Frontend/FrontendPluginRegistry.h"
28	#include "clang/Frontend/TextDiagnosticBuffer.h"
29	#include "clang/Frontend/TextDiagnosticPrinter.h"
30	#include "clang/Lex/Preprocessor.h"
31	#include "clang/Parse/ParseAST.h"
32	#include "clang/Rewrite/Core/Rewriter.h"
33	#include "clang/Rewrite/Frontend/FrontendActions.h"
34	#include "clang/Sema/CodeCompleteConsumer.h"
35	#include "clang/Sema/Sema.h"
36	#include "clang/Sema/SemaConsumer.h"
37
38	#include "llvm/ADT/StringRef.h"
39	#include "llvm/ExecutionEngine/ExecutionEngine.h"
40	#include "llvm/Support/CrashRecoveryContext.h"
41	#include "llvm/Support/Debug.h"
42	#include "llvm/Support/FileSystem.h"
43	#include "llvm/Support/TargetSelect.h"
44
45	#include "llvm/IR/LLVMContext.h"
46	#include "llvm/IR/Module.h"
47	#include "llvm/Support/DynamicLibrary.h"
48	#include "llvm/Support/ErrorHandling.h"
49	#include "llvm/Support/MemoryBuffer.h"
50	#include "llvm/Support/Signals.h"
51	#include "llvm/TargetParser/Host.h"
52
53	#include "ClangDiagnostic.h"
54	#include "ClangExpressionParser.h"
55	#include "ClangUserExpression.h"
56
57	#include "ASTUtils.h"
58	#include "ClangASTSource.h"
59	#include "ClangDiagnostic.h"
60	#include "ClangExpressionDeclMap.h"
61	#include "ClangExpressionHelper.h"
62	#include "ClangExpressionParser.h"
63	#include "ClangHost.h"
64	#include "ClangModulesDeclVendor.h"
65	#include "ClangPersistentVariables.h"
66	#include "IRDynamicChecks.h"
67	#include "IRForTarget.h"
68	#include "ModuleDependencyCollector.h"
69
70	#include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
71	#include "lldb/Core/Debugger.h"
72	#include "lldb/Core/Disassembler.h"
73	#include "lldb/Core/Module.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/SymbolVendor.h"
79	#include "lldb/Target/ExecutionContext.h"
80	#include "lldb/Target/Language.h"
81	#include "lldb/Target/Process.h"
82	#include "lldb/Target/Target.h"
83	#include "lldb/Target/ThreadPlanCallFunction.h"
84	#include "lldb/Utility/DataBufferHeap.h"
85	#include "lldb/Utility/LLDBAssert.h"
86	#include "lldb/Utility/LLDBLog.h"
87	#include "lldb/Utility/Log.h"
88	#include "lldb/Utility/Stream.h"
89	#include "lldb/Utility/StreamString.h"
90	#include "lldb/Utility/StringList.h"
91
92	#include "Plugins/LanguageRuntime/ObjC/ObjCLanguageRuntime.h"
93
94	#include <cctype>
95	#include <memory>
96	#include <optional>
97
98	using namespace clang;
99	using namespace llvm;
100	using namespace lldb_private;
101
102	//===----------------------------------------------------------------------===//
103	// Utility Methods for Clang
104	//===----------------------------------------------------------------------===//
105
106	class ClangExpressionParser::LLDBPreprocessorCallbacks : public PPCallbacks {
107	ClangModulesDeclVendor &m_decl_vendor;
108	ClangPersistentVariables &m_persistent_vars;
109	clang::SourceManager &m_source_mgr;
110	StreamString m_error_stream;
111	bool m_has_errors = false;
112
113	public:
114	LLDBPreprocessorCallbacks(ClangModulesDeclVendor &decl_vendor,
115	ClangPersistentVariables &persistent_vars,
116	clang::SourceManager &source_mgr)
117	: m_decl_vendor(decl_vendor), m_persistent_vars(persistent_vars),
118	m_source_mgr(source_mgr) {}
119
120	void moduleImport(SourceLocation import_location, clang::ModuleIdPath path,
121	const clang::Module * /*null*/) override {
122	// Ignore modules that are imported in the wrapper code as these are not
123	// loaded by the user.
124	llvm::StringRef filename =
125	m_source_mgr.getPresumedLoc(Loc: import_location).getFilename();
126	if (filename == ClangExpressionSourceCode::g_prefix_file_name)
127	return;
128
129	SourceModule module;
130
131	for (const std::pair<IdentifierInfo *, SourceLocation> &component : path)
132	module.path.push_back(x: ConstString(component.first->getName()));
133
134	StreamString error_stream;
135
136	ClangModulesDeclVendor::ModuleVector exported_modules;
137	if (!m_decl_vendor.AddModule(module, exported_modules: &exported_modules, error_stream&: m_error_stream))
138	m_has_errors = true;
139
140	for (ClangModulesDeclVendor::ModuleID module : exported_modules)
141	m_persistent_vars.AddHandLoadedClangModule(module);
142	}
143
144	bool hasErrors() { return m_has_errors; }
145
146	llvm::StringRef getErrorString() { return m_error_stream.GetString(); }
147	};
148
149	static void AddAllFixIts(ClangDiagnostic *diag, const clang::Diagnostic &Info) {
150	for (auto &fix_it : Info.getFixItHints()) {
151	if (fix_it.isNull())
152	continue;
153	diag->AddFixitHint(fixit: fix_it);
154	}
155	}
156
157	class ClangDiagnosticManagerAdapter : public clang::DiagnosticConsumer {
158	public:
159	ClangDiagnosticManagerAdapter(DiagnosticOptions &opts) {
160	DiagnosticOptions *options = new DiagnosticOptions(opts);
161	options->ShowPresumedLoc = true;
162	options->ShowLevel = false;
163	m_os = std::make_shared<llvm::raw_string_ostream>(args&: m_output);
164	m_passthrough =
165	std::make_shared<clang::TextDiagnosticPrinter>(args&: *m_os, args&: options);
166	}
167
168	void ResetManager(DiagnosticManager *manager = nullptr) {
169	m_manager = manager;
170	}
171
172	/// Returns the last ClangDiagnostic message that the DiagnosticManager
173	/// received or a nullptr if the DiagnosticMangager hasn't seen any
174	/// Clang diagnostics yet.
175	ClangDiagnostic *MaybeGetLastClangDiag() const {
176	if (m_manager->Diagnostics().empty())
177	return nullptr;
178	lldb_private::Diagnostic *diag = m_manager->Diagnostics().back().get();
179	ClangDiagnostic *clang_diag = dyn_cast<ClangDiagnostic>(Val: diag);
180	return clang_diag;
181	}
182
183	void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
184	const clang::Diagnostic &Info) override {
185	if (!m_manager) {
186	// We have no DiagnosticManager before/after parsing but we still could
187	// receive diagnostics (e.g., by the ASTImporter failing to copy decls
188	// when we move the expression result ot the ScratchASTContext). Let's at
189	// least log these diagnostics until we find a way to properly render
190	// them and display them to the user.
191	Log *log = GetLog(mask: LLDBLog::Expressions);
192	if (log) {
193	llvm::SmallVector<char, 32> diag_str;
194	Info.FormatDiagnostic(OutStr&: diag_str);
195	diag_str.push_back(Elt: '\0');
196	const char *plain_diag = diag_str.data();
197	LLDB_LOG(log, "Received diagnostic outside parsing: {0}", plain_diag);
198	}
199	return;
200	}
201
202	// Update error/warning counters.
203	DiagnosticConsumer::HandleDiagnostic(DiagLevel, Info);
204
205	// Render diagnostic message to m_output.
206	m_output.clear();
207	m_passthrough->HandleDiagnostic(Level: DiagLevel, Info);
208	m_os->flush();
209
210	lldb_private::DiagnosticSeverity severity;
211	bool make_new_diagnostic = true;
212
213	switch (DiagLevel) {
214	case DiagnosticsEngine::Level::Fatal:
215	case DiagnosticsEngine::Level::Error:
216	severity = eDiagnosticSeverityError;
217	break;
218	case DiagnosticsEngine::Level::Warning:
219	severity = eDiagnosticSeverityWarning;
220	break;
221	case DiagnosticsEngine::Level::Remark:
222	case DiagnosticsEngine::Level::Ignored:
223	severity = eDiagnosticSeverityRemark;
224	break;
225	case DiagnosticsEngine::Level::Note:
226	m_manager->AppendMessageToDiagnostic(str: m_output);
227	make_new_diagnostic = false;
228
229	// 'note:' diagnostics for errors and warnings can also contain Fix-Its.
230	// We add these Fix-Its to the last error diagnostic to make sure
231	// that we later have all Fix-Its related to an 'error' diagnostic when
232	// we apply them to the user expression.
233	auto *clang_diag = MaybeGetLastClangDiag();
234	// If we don't have a previous diagnostic there is nothing to do.
235	// If the previous diagnostic already has its own Fix-Its, assume that
236	// the 'note:' Fix-It is just an alternative way to solve the issue and
237	// ignore these Fix-Its.
238	if (!clang_diag || clang_diag->HasFixIts())
239	break;
240	// Ignore all Fix-Its that are not associated with an error.
241	if (clang_diag->GetSeverity() != eDiagnosticSeverityError)
242	break;
243	AddAllFixIts(diag: clang_diag, Info);
244	break;
245	}
246	if (make_new_diagnostic) {
247	// ClangDiagnostic messages are expected to have no whitespace/newlines
248	// around them.
249	std::string stripped_output =
250	std::string(llvm::StringRef(m_output).trim());
251
252	auto new_diagnostic = std::make_unique<ClangDiagnostic>(
253	args&: stripped_output, args&: severity, args: Info.getID());
254
255	// Don't store away warning fixits, since the compiler doesn't have
256	// enough context in an expression for the warning to be useful.
257	// FIXME: Should we try to filter out FixIts that apply to our generated
258	// code, and not the user's expression?
259	if (severity == eDiagnosticSeverityError)
260	AddAllFixIts(diag: new_diagnostic.get(), Info);
261
262	m_manager->AddDiagnostic(diagnostic: std::move(new_diagnostic));
263	}
264	}
265
266	void BeginSourceFile(const LangOptions &LO, const Preprocessor *PP) override {
267	m_passthrough->BeginSourceFile(LO, PP);
268	}
269
270	void EndSourceFile() override { m_passthrough->EndSourceFile(); }
271
272	private:
273	DiagnosticManager *m_manager = nullptr;
274	std::shared_ptr<clang::TextDiagnosticPrinter> m_passthrough;
275	/// Output stream of m_passthrough.
276	std::shared_ptr<llvm::raw_string_ostream> m_os;
277	/// Output string filled by m_os.
278	std::string m_output;
279	};
280
281	static void SetupModuleHeaderPaths(CompilerInstance *compiler,
282	std::vector<std::string> include_directories,
283	lldb::TargetSP target_sp) {
284	Log *log = GetLog(mask: LLDBLog::Expressions);
285
286	HeaderSearchOptions &search_opts = compiler->getHeaderSearchOpts();
287
288	for (const std::string &dir : include_directories) {
289	search_opts.AddPath(Path: dir, Group: frontend::System, IsFramework: false, IgnoreSysRoot: true);
290	LLDB_LOG(log, "Added user include dir: {0}", dir);
291	}
292
293	llvm::SmallString<128> module_cache;
294	const auto &props = ModuleList::GetGlobalModuleListProperties();
295	props.GetClangModulesCachePath().GetPath(path&: module_cache);
296	search_opts.ModuleCachePath = std::string(module_cache.str());
297	LLDB_LOG(log, "Using module cache path: {0}", module_cache.c_str());
298
299	search_opts.ResourceDir = GetClangResourceDir().GetPath();
300
301	search_opts.ImplicitModuleMaps = true;
302	}
303
304	/// Iff the given identifier is a C++ keyword, remove it from the
305	/// identifier table (i.e., make the token a normal identifier).
306	static void RemoveCppKeyword(IdentifierTable &idents, llvm::StringRef token) {
307	// FIXME: 'using' is used by LLDB for local variables, so we can't remove
308	// this keyword without breaking this functionality.
309	if (token == "using")
310	return;
311	// GCC's '__null' is used by LLDB to define NULL/Nil/nil.
312	if (token == "__null")
313	return;
314
315	LangOptions cpp_lang_opts;
316	cpp_lang_opts.CPlusPlus = true;
317	cpp_lang_opts.CPlusPlus11 = true;
318	cpp_lang_opts.CPlusPlus20 = true;
319
320	clang::IdentifierInfo &ii = idents.get(Name: token);
321	// The identifier has to be a C++-exclusive keyword. if not, then there is
322	// nothing to do.
323	if (!ii.isCPlusPlusKeyword(LangOpts: cpp_lang_opts))
324	return;
325	// If the token is already an identifier, then there is nothing to do.
326	if (ii.getTokenID() == clang::tok::identifier)
327	return;
328	// Otherwise the token is a C++ keyword, so turn it back into a normal
329	// identifier.
330	ii.revertTokenIDToIdentifier();
331	}
332
333	/// Remove all C++ keywords from the given identifier table.
334	static void RemoveAllCppKeywords(IdentifierTable &idents) {
335	#define KEYWORD(NAME, FLAGS) RemoveCppKeyword(idents, llvm::StringRef(#NAME));
336	#include "clang/Basic/TokenKinds.def"
337	}
338
339	/// Configures Clang diagnostics for the expression parser.
340	static void SetupDefaultClangDiagnostics(CompilerInstance &compiler) {
341	// List of Clang warning groups that are not useful when parsing expressions.
342	const std::vector<const char *> groupsToIgnore = {
343	"unused-value",
344	"odr",
345	"unused-getter-return-value",
346	};
347	for (const char *group : groupsToIgnore) {
348	compiler.getDiagnostics().setSeverityForGroup(
349	Flavor: clang::diag::Flavor::WarningOrError, Group: group,
350	Map: clang::diag::Severity::Ignored, Loc: SourceLocation());
351	}
352	}
353
354	//===----------------------------------------------------------------------===//
355	// Implementation of ClangExpressionParser
356	//===----------------------------------------------------------------------===//
357
358	ClangExpressionParser::ClangExpressionParser(
359	ExecutionContextScope *exe_scope, Expression &expr,
360	bool generate_debug_info, std::vector<std::string> include_directories,
361	std::string filename)
362	: ExpressionParser(exe_scope, expr, generate_debug_info), m_compiler(),
363	m_pp_callbacks(nullptr),
364	m_include_directories(std::move(include_directories)),
365	m_filename(std::move(filename)) {
366	Log *log = GetLog(mask: LLDBLog::Expressions);
367
368	// We can't compile expressions without a target. So if the exe_scope is
369	// null or doesn't have a target, then we just need to get out of here. I'll
370	// lldbassert and not make any of the compiler objects since
371	// I can't return errors directly from the constructor. Further calls will
372	// check if the compiler was made and
373	// bag out if it wasn't.
374
375	if (!exe_scope) {
376	lldbassert(exe_scope &&
377	"Can't make an expression parser with a null scope.");
378	return;
379	}
380
381	lldb::TargetSP target_sp;
382	target_sp = exe_scope->CalculateTarget();
383	if (!target_sp) {
384	lldbassert(target_sp.get() &&
385	"Can't make an expression parser with a null target.");
386	return;
387	}
388
389	// 1. Create a new compiler instance.
390	m_compiler = std::make_unique<CompilerInstance>();
391
392	// Make sure clang uses the same VFS as LLDB.
393	m_compiler->createFileManager(VFS: FileSystem::Instance().GetVirtualFileSystem());
394
395	lldb::LanguageType frame_lang =
396	expr.Language(); // defaults to lldb::eLanguageTypeUnknown
397
398	std::string abi;
399	ArchSpec target_arch;
400	target_arch = target_sp->GetArchitecture();
401
402	const auto target_machine = target_arch.GetMachine();
403
404	// If the expression is being evaluated in the context of an existing stack
405	// frame, we introspect to see if the language runtime is available.
406
407	lldb::StackFrameSP frame_sp = exe_scope->CalculateStackFrame();
408	lldb::ProcessSP process_sp = exe_scope->CalculateProcess();
409
410	// Make sure the user hasn't provided a preferred execution language with
411	// `expression --language X -- ...`
412	if (frame_sp && frame_lang == lldb::eLanguageTypeUnknown)
413	frame_lang = frame_sp->GetLanguage();
414
415	if (process_sp && frame_lang != lldb::eLanguageTypeUnknown) {
416	LLDB_LOGF(log, "Frame has language of type %s",
417	Language::GetNameForLanguageType(frame_lang));
418	}
419
420	// 2. Configure the compiler with a set of default options that are
421	// appropriate for most situations.
422	if (target_arch.IsValid()) {
423	std::string triple = target_arch.GetTriple().str();
424	m_compiler->getTargetOpts().Triple = triple;
425	LLDB_LOGF(log, "Using %s as the target triple",
426	m_compiler->getTargetOpts().Triple.c_str());
427	} else {
428	// If we get here we don't have a valid target and just have to guess.
429	// Sometimes this will be ok to just use the host target triple (when we
430	// evaluate say "2+3", but other expressions like breakpoint conditions and
431	// other things that _are_ target specific really shouldn't just be using
432	// the host triple. In such a case the language runtime should expose an
433	// overridden options set (3), below.
434	m_compiler->getTargetOpts().Triple = llvm::sys::getDefaultTargetTriple();
435	LLDB_LOGF(log, "Using default target triple of %s",
436	m_compiler->getTargetOpts().Triple.c_str());
437	}
438	// Now add some special fixes for known architectures: Any arm32 iOS
439	// environment, but not on arm64
440	if (m_compiler->getTargetOpts().Triple.find(s: "arm64") == std::string::npos &&
441	m_compiler->getTargetOpts().Triple.find(s: "arm") != std::string::npos &&
442	m_compiler->getTargetOpts().Triple.find(s: "ios") != std::string::npos) {
443	m_compiler->getTargetOpts().ABI = "apcs-gnu";
444	}
445	// Supported subsets of x86
446	if (target_machine == llvm::Triple::x86 ||
447	target_machine == llvm::Triple::x86_64) {
448	m_compiler->getTargetOpts().FeaturesAsWritten.push_back(x: "+sse");
449	m_compiler->getTargetOpts().FeaturesAsWritten.push_back(x: "+sse2");
450	}
451
452	// Set the target CPU to generate code for. This will be empty for any CPU
453	// that doesn't really need to make a special
454	// CPU string.
455	m_compiler->getTargetOpts().CPU = target_arch.GetClangTargetCPU();
456
457	// Set the target ABI
458	abi = GetClangTargetABI(target_arch);
459	if (!abi.empty())
460	m_compiler->getTargetOpts().ABI = abi;
461
462	// 3. Create and install the target on the compiler.
463	m_compiler->createDiagnostics();
464	// Limit the number of error diagnostics we emit.
465	// A value of 0 means no limit for both LLDB and Clang.
466	m_compiler->getDiagnostics().setErrorLimit(target_sp->GetExprErrorLimit());
467
468	auto target_info = TargetInfo::CreateTargetInfo(
469	Diags&: m_compiler->getDiagnostics(), Opts: m_compiler->getInvocation().TargetOpts);
470	if (log) {
471	LLDB_LOGF(log, "Target datalayout string: '%s'",
472	target_info->getDataLayoutString());
473	LLDB_LOGF(log, "Target ABI: '%s'", target_info->getABI().str().c_str());
474	LLDB_LOGF(log, "Target vector alignment: %d",
475	target_info->getMaxVectorAlign());
476	}
477	m_compiler->setTarget(target_info);
478
479	assert(m_compiler->hasTarget());
480
481	// 4. Set language options.
482	lldb::LanguageType language = expr.Language();
483	LangOptions &lang_opts = m_compiler->getLangOpts();
484
485	switch (language) {
486	case lldb::eLanguageTypeC:
487	case lldb::eLanguageTypeC89:
488	case lldb::eLanguageTypeC99:
489	case lldb::eLanguageTypeC11:
490	// FIXME: the following language option is a temporary workaround,
491	// to "ask for C, get C++."
492	// For now, the expression parser must use C++ anytime the language is a C
493	// family language, because the expression parser uses features of C++ to
494	// capture values.
495	lang_opts.CPlusPlus = true;
496	break;
497	case lldb::eLanguageTypeObjC:
498	lang_opts.ObjC = true;
499	// FIXME: the following language option is a temporary workaround,
500	// to "ask for ObjC, get ObjC++" (see comment above).
501	lang_opts.CPlusPlus = true;
502
503	// Clang now sets as default C++14 as the default standard (with
504	// GNU extensions), so we do the same here to avoid mismatches that
505	// cause compiler error when evaluating expressions (e.g. nullptr not found
506	// as it's a C++11 feature). Currently lldb evaluates C++14 as C++11 (see
507	// two lines below) so we decide to be consistent with that, but this could
508	// be re-evaluated in the future.
509	lang_opts.CPlusPlus11 = true;
510	break;
511	case lldb::eLanguageTypeC_plus_plus_20:
512	lang_opts.CPlusPlus20 = true;
513	[[fallthrough]];
514	case lldb::eLanguageTypeC_plus_plus_17:
515	// FIXME: add a separate case for CPlusPlus14. Currently folded into C++17
516	// because C++14 is the default standard for Clang but enabling CPlusPlus14
517	// expression evaluatino doesn't pass the test-suite cleanly.
518	lang_opts.CPlusPlus14 = true;
519	lang_opts.CPlusPlus17 = true;
520	[[fallthrough]];
521	case lldb::eLanguageTypeC_plus_plus:
522	case lldb::eLanguageTypeC_plus_plus_11:
523	case lldb::eLanguageTypeC_plus_plus_14:
524	lang_opts.CPlusPlus11 = true;
525	m_compiler->getHeaderSearchOpts().UseLibcxx = true;
526	[[fallthrough]];
527	case lldb::eLanguageTypeC_plus_plus_03:
528	lang_opts.CPlusPlus = true;
529	if (process_sp
530	// We're stopped in a frame without debug-info. The user probably
531	// intends to make global queries (which should include Objective-C).
532	&& !(frame_sp && frame_sp->HasDebugInformation()))
533	lang_opts.ObjC =
534	process_sp->GetLanguageRuntime(language: lldb::eLanguageTypeObjC) != nullptr;
535	break;
536	case lldb::eLanguageTypeObjC_plus_plus:
537	case lldb::eLanguageTypeUnknown:
538	default:
539	lang_opts.ObjC = true;
540	lang_opts.CPlusPlus = true;
541	lang_opts.CPlusPlus11 = true;
542	m_compiler->getHeaderSearchOpts().UseLibcxx = true;
543	break;
544	}
545
546	lang_opts.Bool = true;
547	lang_opts.WChar = true;
548	lang_opts.Blocks = true;
549	lang_opts.DebuggerSupport =
550	true; // Features specifically for debugger clients
551	if (expr.DesiredResultType() == Expression::eResultTypeId)
552	lang_opts.DebuggerCastResultToId = true;
553
554	lang_opts.CharIsSigned = ArchSpec(m_compiler->getTargetOpts().Triple.c_str())
555	.CharIsSignedByDefault();
556
557	// Spell checking is a nice feature, but it ends up completing a lot of types
558	// that we didn't strictly speaking need to complete. As a result, we spend a
559	// long time parsing and importing debug information.
560	lang_opts.SpellChecking = false;
561
562	auto *clang_expr = dyn_cast<ClangUserExpression>(Val: &m_expr);
563	if (clang_expr && clang_expr->DidImportCxxModules()) {
564	LLDB_LOG(log, "Adding lang options for importing C++ modules");
565
566	lang_opts.Modules = true;
567	// We want to implicitly build modules.
568	lang_opts.ImplicitModules = true;
569	// To automatically import all submodules when we import 'std'.
570	lang_opts.ModulesLocalVisibility = false;
571
572	// We use the @import statements, so we need this:
573	// FIXME: We could use the modules-ts, but that currently doesn't work.
574	lang_opts.ObjC = true;
575
576	// Options we need to parse libc++ code successfully.
577	// FIXME: We should ask the driver for the appropriate default flags.
578	lang_opts.GNUMode = true;
579	lang_opts.GNUKeywords = true;
580	lang_opts.CPlusPlus11 = true;
581	lang_opts.BuiltinHeadersInSystemModules = true;
582
583	// The Darwin libc expects this macro to be set.
584	lang_opts.GNUCVersion = 40201;
585
586	SetupModuleHeaderPaths(compiler: m_compiler.get(), include_directories: m_include_directories,
587	target_sp);
588	}
589
590	if (process_sp && lang_opts.ObjC) {
591	if (auto *runtime = ObjCLanguageRuntime::Get(process&: *process_sp)) {
592	switch (runtime->GetRuntimeVersion()) {
593	case ObjCLanguageRuntime::ObjCRuntimeVersions::eAppleObjC_V2:
594	lang_opts.ObjCRuntime.set(kind: ObjCRuntime::MacOSX, version: VersionTuple(10, 7));
595	break;
596	case ObjCLanguageRuntime::ObjCRuntimeVersions::eObjC_VersionUnknown:
597	case ObjCLanguageRuntime::ObjCRuntimeVersions::eAppleObjC_V1:
598	lang_opts.ObjCRuntime.set(kind: ObjCRuntime::FragileMacOSX,
599	version: VersionTuple(10, 7));
600	break;
601	case ObjCLanguageRuntime::ObjCRuntimeVersions::eGNUstep_libobjc2:
602	lang_opts.ObjCRuntime.set(kind: ObjCRuntime::GNUstep, version: VersionTuple(2, 0));
603	break;
604	}
605
606	if (runtime->HasNewLiteralsAndIndexing())
607	lang_opts.DebuggerObjCLiteral = true;
608	}
609	}
610
611	lang_opts.ThreadsafeStatics = false;
612	lang_opts.AccessControl = false; // Debuggers get universal access
613	lang_opts.DollarIdents = true; // $ indicates a persistent variable name
614	// We enable all builtin functions beside the builtins from libc/libm (e.g.
615	// 'fopen'). Those libc functions are already correctly handled by LLDB, and
616	// additionally enabling them as expandable builtins is breaking Clang.
617	lang_opts.NoBuiltin = true;
618
619	// Set CodeGen options
620	m_compiler->getCodeGenOpts().EmitDeclMetadata = true;
621	m_compiler->getCodeGenOpts().InstrumentFunctions = false;
622	m_compiler->getCodeGenOpts().setFramePointer(
623	CodeGenOptions::FramePointerKind::All);
624	if (generate_debug_info)
625	m_compiler->getCodeGenOpts().setDebugInfo(codegenoptions::FullDebugInfo);
626	else
627	m_compiler->getCodeGenOpts().setDebugInfo(codegenoptions::NoDebugInfo);
628
629	// Disable some warnings.
630	SetupDefaultClangDiagnostics(*m_compiler);
631
632	// Inform the target of the language options
633	//
634	// FIXME: We shouldn't need to do this, the target should be immutable once
635	// created. This complexity should be lifted elsewhere.
636	m_compiler->getTarget().adjust(Diags&: m_compiler->getDiagnostics(),
637	Opts&: m_compiler->getLangOpts());
638
639	// 5. Set up the diagnostic buffer for reporting errors
640
641	auto diag_mgr = new ClangDiagnosticManagerAdapter(
642	m_compiler->getDiagnostics().getDiagnosticOptions());
643	m_compiler->getDiagnostics().setClient(client: diag_mgr);
644
645	// 6. Set up the source management objects inside the compiler
646	m_compiler->createFileManager();
647	if (!m_compiler->hasSourceManager())
648	m_compiler->createSourceManager(FileMgr&: m_compiler->getFileManager());
649	m_compiler->createPreprocessor(TUKind: TU_Complete);
650
651	switch (language) {
652	case lldb::eLanguageTypeC:
653	case lldb::eLanguageTypeC89:
654	case lldb::eLanguageTypeC99:
655	case lldb::eLanguageTypeC11:
656	case lldb::eLanguageTypeObjC:
657	// This is not a C++ expression but we enabled C++ as explained above.
658	// Remove all C++ keywords from the PP so that the user can still use
659	// variables that have C++ keywords as names (e.g. 'int template;').
660	RemoveAllCppKeywords(idents&: m_compiler->getPreprocessor().getIdentifierTable());
661	break;
662	default:
663	break;
664	}
665
666	if (auto *clang_persistent_vars = llvm::cast<ClangPersistentVariables>(
667	Val: target_sp->GetPersistentExpressionStateForLanguage(
668	language: lldb::eLanguageTypeC))) {
669	if (std::shared_ptr<ClangModulesDeclVendor> decl_vendor =
670	clang_persistent_vars->GetClangModulesDeclVendor()) {
671	std::unique_ptr<PPCallbacks> pp_callbacks(
672	new LLDBPreprocessorCallbacks(*decl_vendor, *clang_persistent_vars,
673	m_compiler->getSourceManager()));
674	m_pp_callbacks =
675	static_cast<LLDBPreprocessorCallbacks *>(pp_callbacks.get());
676	m_compiler->getPreprocessor().addPPCallbacks(C: std::move(pp_callbacks));
677	}
678	}
679
680	// 7. Most of this we get from the CompilerInstance, but we also want to give
681	// the context an ExternalASTSource.
682
683	auto &PP = m_compiler->getPreprocessor();
684	auto &builtin_context = PP.getBuiltinInfo();
685	builtin_context.initializeBuiltins(Table&: PP.getIdentifierTable(),
686	LangOpts: m_compiler->getLangOpts());
687
688	m_compiler->createASTContext();
689	clang::ASTContext &ast_context = m_compiler->getASTContext();
690
691	m_ast_context = std::make_shared<TypeSystemClang>(
692	args: "Expression ASTContext for '" + m_filename + "'", args&: ast_context);
693
694	std::string module_name("$__lldb_module");
695
696	m_llvm_context = std::make_unique<LLVMContext>();
697	m_code_generator.reset(p: CreateLLVMCodeGen(
698	Diags&: m_compiler->getDiagnostics(), ModuleName: module_name,
699	FS: &m_compiler->getVirtualFileSystem(), HeaderSearchOpts: m_compiler->getHeaderSearchOpts(),
700	PreprocessorOpts: m_compiler->getPreprocessorOpts(), CGO: m_compiler->getCodeGenOpts(),
701	C&: *m_llvm_context));
702	}
703
704	ClangExpressionParser::~ClangExpressionParser() = default;
705
706	namespace {
707
708	/// \class CodeComplete
709	///
710	/// A code completion consumer for the clang Sema that is responsible for
711	/// creating the completion suggestions when a user requests completion
712	/// of an incomplete `expr` invocation.
713	class CodeComplete : public CodeCompleteConsumer {
714	CodeCompletionTUInfo m_info;
715
716	std::string m_expr;
717	unsigned m_position = 0;
718	/// The printing policy we use when printing declarations for our completion
719	/// descriptions.
720	clang::PrintingPolicy m_desc_policy;
721
722	struct CompletionWithPriority {
723	CompletionResult::Completion completion;
724	/// See CodeCompletionResult::Priority;
725	unsigned Priority;
726
727	/// Establishes a deterministic order in a list of CompletionWithPriority.
728	/// The order returned here is the order in which the completions are
729	/// displayed to the user.
730	bool operator<(const CompletionWithPriority &o) const {
731	// High priority results should come first.
732	if (Priority != o.Priority)
733	return Priority > o.Priority;
734
735	// Identical priority, so just make sure it's a deterministic order.
736	return completion.GetUniqueKey() < o.completion.GetUniqueKey();
737	}
738	};
739
740	/// The stored completions.
741	/// Warning: These are in a non-deterministic order until they are sorted
742	/// and returned back to the caller.
743	std::vector<CompletionWithPriority> m_completions;
744
745	/// Returns true if the given character can be used in an identifier.
746	/// This also returns true for numbers because for completion we usually
747	/// just iterate backwards over iterators.
748	///
749	/// Note: lldb uses '$' in its internal identifiers, so we also allow this.
750	static bool IsIdChar(char c) {
751	return c == '_' || std::isalnum(c) || c == '$';
752	}
753
754	/// Returns true if the given character is used to separate arguments
755	/// in the command line of lldb.
756	static bool IsTokenSeparator(char c) { return c == ' ' || c == '\t'; }
757
758	/// Drops all tokens in front of the expression that are unrelated for
759	/// the completion of the cmd line. 'unrelated' means here that the token
760	/// is not interested for the lldb completion API result.
761	StringRef dropUnrelatedFrontTokens(StringRef cmd) const {
762	if (cmd.empty())
763	return cmd;
764
765	// If we are at the start of a word, then all tokens are unrelated to
766	// the current completion logic.
767	if (IsTokenSeparator(c: cmd.back()))
768	return StringRef();
769
770	// Remove all previous tokens from the string as they are unrelated
771	// to completing the current token.
772	StringRef to_remove = cmd;
773	while (!to_remove.empty() && !IsTokenSeparator(c: to_remove.back())) {
774	to_remove = to_remove.drop_back();
775	}
776	cmd = cmd.drop_front(N: to_remove.size());
777
778	return cmd;
779	}
780
781	/// Removes the last identifier token from the given cmd line.
782	StringRef removeLastToken(StringRef cmd) const {
783	while (!cmd.empty() && IsIdChar(c: cmd.back())) {
784	cmd = cmd.drop_back();
785	}
786	return cmd;
787	}
788
789	/// Attempts to merge the given completion from the given position into the
790	/// existing command. Returns the completion string that can be returned to
791	/// the lldb completion API.
792	std::string mergeCompletion(StringRef existing, unsigned pos,
793	StringRef completion) const {
794	StringRef existing_command = existing.substr(Start: 0, N: pos);
795	// We rewrite the last token with the completion, so let's drop that
796	// token from the command.
797	existing_command = removeLastToken(cmd: existing_command);
798	// We also should remove all previous tokens from the command as they
799	// would otherwise be added to the completion that already has the
800	// completion.
801	existing_command = dropUnrelatedFrontTokens(cmd: existing_command);
802	return existing_command.str() + completion.str();
803	}
804
805	public:
806	/// Constructs a CodeComplete consumer that can be attached to a Sema.
807	///
808	/// \param[out] expr
809	/// The whole expression string that we are currently parsing. This
810	/// string needs to be equal to the input the user typed, and NOT the
811	/// final code that Clang is parsing.
812	/// \param[out] position
813	/// The character position of the user cursor in the `expr` parameter.
814	///
815	CodeComplete(clang::LangOptions ops, std::string expr, unsigned position)
816	: CodeCompleteConsumer(CodeCompleteOptions()),
817	m_info(std::make_shared<GlobalCodeCompletionAllocator>()), m_expr(expr),
818	m_position(position), m_desc_policy(ops) {
819
820	// Ensure that the printing policy is producing a description that is as
821	// short as possible.
822	m_desc_policy.SuppressScope = true;
823	m_desc_policy.SuppressTagKeyword = true;
824	m_desc_policy.FullyQualifiedName = false;
825	m_desc_policy.TerseOutput = true;
826	m_desc_policy.IncludeNewlines = false;
827	m_desc_policy.UseVoidForZeroParams = false;
828	m_desc_policy.Bool = true;
829	}
830
831	/// \name Code-completion filtering
832	/// Check if the result should be filtered out.
833	bool isResultFilteredOut(StringRef Filter,
834	CodeCompletionResult Result) override {
835	// This code is mostly copied from CodeCompleteConsumer.
836	switch (Result.Kind) {
837	case CodeCompletionResult::RK_Declaration:
838	return !(
839	Result.Declaration->getIdentifier() &&
840	Result.Declaration->getIdentifier()->getName().starts_with(Prefix: Filter));
841	case CodeCompletionResult::RK_Keyword:
842	return !StringRef(Result.Keyword).starts_with(Prefix: Filter);
843	case CodeCompletionResult::RK_Macro:
844	return !Result.Macro->getName().starts_with(Prefix: Filter);
845	case CodeCompletionResult::RK_Pattern:
846	return !StringRef(Result.Pattern->getAsString()).starts_with(Prefix: Filter);
847	}
848	// If we trigger this assert or the above switch yields a warning, then
849	// CodeCompletionResult has been enhanced with more kinds of completion
850	// results. Expand the switch above in this case.
851	assert(false && "Unknown completion result type?");
852	// If we reach this, then we should just ignore whatever kind of unknown
853	// result we got back. We probably can't turn it into any kind of useful
854	// completion suggestion with the existing code.
855	return true;
856	}
857
858	private:
859	/// Generate the completion strings for the given CodeCompletionResult.
860	/// Note that this function has to process results that could come in
861	/// non-deterministic order, so this function should have no side effects.
862	/// To make this easier to enforce, this function and all its parameters
863	/// should always be const-qualified.
864	/// \return Returns std::nullopt if no completion should be provided for the
865	/// given CodeCompletionResult.
866	std::optional<CompletionWithPriority>
867	getCompletionForResult(const CodeCompletionResult &R) const {
868	std::string ToInsert;
869	std::string Description;
870	// Handle the different completion kinds that come from the Sema.
871	switch (R.Kind) {
872	case CodeCompletionResult::RK_Declaration: {
873	const NamedDecl *D = R.Declaration;
874	ToInsert = R.Declaration->getNameAsString();
875	// If we have a function decl that has no arguments we want to
876	// complete the empty parantheses for the user. If the function has
877	// arguments, we at least complete the opening bracket.
878	if (const FunctionDecl *F = dyn_cast<FunctionDecl>(Val: D)) {
879	if (F->getNumParams() == 0)
880	ToInsert += "()";
881	else
882	ToInsert += "(";
883	raw_string_ostream OS(Description);
884	F->print(OS, m_desc_policy, false);
885	OS.flush();
886	} else if (const VarDecl *V = dyn_cast<VarDecl>(Val: D)) {
887	Description = V->getType().getAsString(m_desc_policy);
888	} else if (const FieldDecl *F = dyn_cast<FieldDecl>(Val: D)) {
889	Description = F->getType().getAsString(m_desc_policy);
890	} else if (const NamespaceDecl *N = dyn_cast<NamespaceDecl>(Val: D)) {
891	// If we try to complete a namespace, then we can directly append
892	// the '::'.
893	if (!N->isAnonymousNamespace())
894	ToInsert += "::";
895	}
896	break;
897	}
898	case CodeCompletionResult::RK_Keyword:
899	ToInsert = R.Keyword;
900	break;
901	case CodeCompletionResult::RK_Macro:
902	ToInsert = R.Macro->getName().str();
903	break;
904	case CodeCompletionResult::RK_Pattern:
905	ToInsert = R.Pattern->getTypedText();
906	break;
907	}
908	// We also filter some internal lldb identifiers here. The user
909	// shouldn't see these.
910	if (llvm::StringRef(ToInsert).starts_with(Prefix: "$__lldb_"))
911	return std::nullopt;
912	if (ToInsert.empty())
913	return std::nullopt;
914	// Merge the suggested Token into the existing command line to comply
915	// with the kind of result the lldb API expects.
916	std::string CompletionSuggestion =
917	mergeCompletion(existing: m_expr, pos: m_position, completion: ToInsert);
918
919	CompletionResult::Completion completion(CompletionSuggestion, Description,
920	CompletionMode::Normal);
921	return {{.completion: completion, .Priority: R.Priority}};
922	}
923
924	public:
925	/// Adds the completions to the given CompletionRequest.
926	void GetCompletions(CompletionRequest &request) {
927	// Bring m_completions into a deterministic order and pass it on to the
928	// CompletionRequest.
929	llvm::sort(C&: m_completions);
930
931	for (const CompletionWithPriority &C : m_completions)
932	request.AddCompletion(completion: C.completion.GetCompletion(),
933	description: C.completion.GetDescription(),
934	mode: C.completion.GetMode());
935	}
936
937	/// \name Code-completion callbacks
938	/// Process the finalized code-completion results.
939	void ProcessCodeCompleteResults(Sema &SemaRef, CodeCompletionContext Context,
940	CodeCompletionResult *Results,
941	unsigned NumResults) override {
942
943	// The Sema put the incomplete token we try to complete in here during
944	// lexing, so we need to retrieve it here to know what we are completing.
945	StringRef Filter = SemaRef.getPreprocessor().getCodeCompletionFilter();
946
947	// Iterate over all the results. Filter out results we don't want and
948	// process the rest.
949	for (unsigned I = 0; I != NumResults; ++I) {
950	// Filter the results with the information from the Sema.
951	if (!Filter.empty() && isResultFilteredOut(Filter, Result: Results[I]))
952	continue;
953
954	CodeCompletionResult &R = Results[I];
955	std::optional<CompletionWithPriority> CompletionAndPriority =
956	getCompletionForResult(R);
957	if (!CompletionAndPriority)
958	continue;
959	m_completions.push_back(x: *CompletionAndPriority);
960	}
961	}
962
963	/// \param S the semantic-analyzer object for which code-completion is being
964	/// done.
965	///
966	/// \param CurrentArg the index of the current argument.
967	///
968	/// \param Candidates an array of overload candidates.
969	///
970	/// \param NumCandidates the number of overload candidates
971	void ProcessOverloadCandidates(Sema &S, unsigned CurrentArg,
972	OverloadCandidate *Candidates,
973	unsigned NumCandidates,
974	SourceLocation OpenParLoc,
975	bool Braced) override {
976	// At the moment we don't filter out any overloaded candidates.
977	}
978
979	CodeCompletionAllocator &getAllocator() override {
980	return m_info.getAllocator();
981	}
982
983	CodeCompletionTUInfo &getCodeCompletionTUInfo() override { return m_info; }
984	};
985	} // namespace
986
987	bool ClangExpressionParser::Complete(CompletionRequest &request, unsigned line,
988	unsigned pos, unsigned typed_pos) {
989	DiagnosticManager mgr;
990	// We need the raw user expression here because that's what the CodeComplete
991	// class uses to provide completion suggestions.
992	// However, the `Text` method only gives us the transformed expression here.
993	// To actually get the raw user input here, we have to cast our expression to
994	// the LLVMUserExpression which exposes the right API. This should never fail
995	// as we always have a ClangUserExpression whenever we call this.
996	ClangUserExpression *llvm_expr = cast<ClangUserExpression>(Val: &m_expr);
997	CodeComplete CC(m_compiler->getLangOpts(), llvm_expr->GetUserText(),
998	typed_pos);
999	// We don't need a code generator for parsing.
1000	m_code_generator.reset();
1001	// Start parsing the expression with our custom code completion consumer.
1002	ParseInternal(diagnostic_manager&: mgr, completion: &CC, completion_line: line, completion_column: pos);
1003	CC.GetCompletions(request);
1004	return true;
1005	}
1006
1007	unsigned ClangExpressionParser::Parse(DiagnosticManager &diagnostic_manager) {
1008	return ParseInternal(diagnostic_manager);
1009	}
1010
1011	unsigned
1012	ClangExpressionParser::ParseInternal(DiagnosticManager &diagnostic_manager,
1013	CodeCompleteConsumer *completion_consumer,
1014	unsigned completion_line,
1015	unsigned completion_column) {
1016	ClangDiagnosticManagerAdapter *adapter =
1017	static_cast<ClangDiagnosticManagerAdapter *>(
1018	m_compiler->getDiagnostics().getClient());
1019
1020	adapter->ResetManager(manager: &diagnostic_manager);
1021
1022	const char *expr_text = m_expr.Text();
1023
1024	clang::SourceManager &source_mgr = m_compiler->getSourceManager();
1025	bool created_main_file = false;
1026
1027	// Clang wants to do completion on a real file known by Clang's file manager,
1028	// so we have to create one to make this work.
1029	// TODO: We probably could also simulate to Clang's file manager that there
1030	// is a real file that contains our code.
1031	bool should_create_file = completion_consumer != nullptr;
1032
1033	// We also want a real file on disk if we generate full debug info.
1034	should_create_file |= m_compiler->getCodeGenOpts().getDebugInfo() ==
1035	codegenoptions::FullDebugInfo;
1036
1037	if (should_create_file) {
1038	int temp_fd = -1;
1039	llvm::SmallString<128> result_path;
1040	if (FileSpec tmpdir_file_spec = HostInfo::GetProcessTempDir()) {
1041	tmpdir_file_spec.AppendPathComponent(component: "lldb-%%%%%%.expr");
1042	std::string temp_source_path = tmpdir_file_spec.GetPath();
1043	llvm::sys::fs::createUniqueFile(Model: temp_source_path, ResultFD&: temp_fd, ResultPath&: result_path);
1044	} else {
1045	llvm::sys::fs::createTemporaryFile(Prefix: "lldb", Suffix: "expr", ResultFD&: temp_fd, ResultPath&: result_path);
1046	}
1047
1048	if (temp_fd != -1) {
1049	lldb_private::NativeFile file(temp_fd, File::eOpenOptionWriteOnly, true);
1050	const size_t expr_text_len = strlen(s: expr_text);
1051	size_t bytes_written = expr_text_len;
1052	if (file.Write(buf: expr_text, num_bytes&: bytes_written).Success()) {
1053	if (bytes_written == expr_text_len) {
1054	file.Close();
1055	if (auto fileEntry = m_compiler->getFileManager().getOptionalFileRef(
1056	Filename: result_path)) {
1057	source_mgr.setMainFileID(source_mgr.createFileID(
1058	SourceFile: *fileEntry,
1059	IncludePos: SourceLocation(), FileCharacter: SrcMgr::C_User));
1060	created_main_file = true;
1061	}
1062	}
1063	}
1064	}
1065	}
1066
1067	if (!created_main_file) {
1068	std::unique_ptr<MemoryBuffer> memory_buffer =
1069	MemoryBuffer::getMemBufferCopy(InputData: expr_text, BufferName: m_filename);
1070	source_mgr.setMainFileID(source_mgr.createFileID(Buffer: std::move(memory_buffer)));
1071	}
1072
1073	adapter->BeginSourceFile(LO: m_compiler->getLangOpts(),
1074	PP: &m_compiler->getPreprocessor());
1075
1076	ClangExpressionHelper *type_system_helper =
1077	dyn_cast<ClangExpressionHelper>(Val: m_expr.GetTypeSystemHelper());
1078
1079	// If we want to parse for code completion, we need to attach our code
1080	// completion consumer to the Sema and specify a completion position.
1081	// While parsing the Sema will call this consumer with the provided
1082	// completion suggestions.
1083	if (completion_consumer) {
1084	auto main_file =
1085	source_mgr.getFileEntryRefForID(FID: source_mgr.getMainFileID());
1086	auto &PP = m_compiler->getPreprocessor();
1087	// Lines and columns start at 1 in Clang, but code completion positions are
1088	// indexed from 0, so we need to add 1 to the line and column here.
1089	++completion_line;
1090	++completion_column;
1091	PP.SetCodeCompletionPoint(File: *main_file, Line: completion_line, Column: completion_column);
1092	}
1093
1094	ASTConsumer *ast_transformer =
1095	type_system_helper->ASTTransformer(passthrough: m_code_generator.get());
1096
1097	std::unique_ptr<clang::ASTConsumer> Consumer;
1098	if (ast_transformer) {
1099	Consumer = std::make_unique<ASTConsumerForwarder>(args&: ast_transformer);
1100	} else if (m_code_generator) {
1101	Consumer = std::make_unique<ASTConsumerForwarder>(args: m_code_generator.get());
1102	} else {
1103	Consumer = std::make_unique<ASTConsumer>();
1104	}
1105
1106	clang::ASTContext &ast_context = m_compiler->getASTContext();
1107
1108	m_compiler->setSema(new Sema(m_compiler->getPreprocessor(), ast_context,
1109	*Consumer, TU_Complete, completion_consumer));
1110	m_compiler->setASTConsumer(std::move(Consumer));
1111
1112	if (ast_context.getLangOpts().Modules) {
1113	m_compiler->createASTReader();
1114	m_ast_context->setSema(&m_compiler->getSema());
1115	}
1116
1117	ClangExpressionDeclMap *decl_map = type_system_helper->DeclMap();
1118	if (decl_map) {
1119	decl_map->InstallCodeGenerator(code_gen: &m_compiler->getASTConsumer());
1120	decl_map->InstallDiagnosticManager(diag_manager&: diagnostic_manager);
1121
1122	clang::ExternalASTSource *ast_source = decl_map->CreateProxy();
1123
1124	if (ast_context.getExternalSource()) {
1125	auto module_wrapper =
1126	new ExternalASTSourceWrapper(ast_context.getExternalSource());
1127
1128	auto ast_source_wrapper = new ExternalASTSourceWrapper(ast_source);
1129
1130	auto multiplexer =
1131	new SemaSourceWithPriorities(*module_wrapper, *ast_source_wrapper);
1132	IntrusiveRefCntPtr<ExternalASTSource> Source(multiplexer);
1133	ast_context.setExternalSource(Source);
1134	} else {
1135	ast_context.setExternalSource(ast_source);
1136	}
1137	decl_map->InstallASTContext(ast_context&: *m_ast_context);
1138	}
1139
1140	// Check that the ASTReader is properly attached to ASTContext and Sema.
1141	if (ast_context.getLangOpts().Modules) {
1142	assert(m_compiler->getASTContext().getExternalSource() &&
1143	"ASTContext doesn't know about the ASTReader?");
1144	assert(m_compiler->getSema().getExternalSource() &&
1145	"Sema doesn't know about the ASTReader?");
1146	}
1147
1148	{
1149	llvm::CrashRecoveryContextCleanupRegistrar<Sema> CleanupSema(
1150	&m_compiler->getSema());
1151	ParseAST(S&: m_compiler->getSema(), PrintStats: false, SkipFunctionBodies: false);
1152	}
1153
1154	// Make sure we have no pointer to the Sema we are about to destroy.
1155	if (ast_context.getLangOpts().Modules)
1156	m_ast_context->setSema(nullptr);
1157	// Destroy the Sema. This is necessary because we want to emulate the
1158	// original behavior of ParseAST (which also destroys the Sema after parsing).
1159	m_compiler->setSema(nullptr);
1160
1161	adapter->EndSourceFile();
1162
1163	unsigned num_errors = adapter->getNumErrors();
1164
1165	if (m_pp_callbacks && m_pp_callbacks->hasErrors()) {
1166	num_errors++;
1167	diagnostic_manager.PutString(severity: eDiagnosticSeverityError,
1168	str: "while importing modules:");
1169	diagnostic_manager.AppendMessageToDiagnostic(
1170	str: m_pp_callbacks->getErrorString());
1171	}
1172
1173	if (!num_errors) {
1174	type_system_helper->CommitPersistentDecls();
1175	}
1176
1177	adapter->ResetManager();
1178
1179	return num_errors;
1180	}
1181
1182	std::string
1183	ClangExpressionParser::GetClangTargetABI(const ArchSpec &target_arch) {
1184	std::string abi;
1185
1186	if (target_arch.IsMIPS()) {
1187	switch (target_arch.GetFlags() & ArchSpec::eMIPSABI_mask) {
1188	case ArchSpec::eMIPSABI_N64:
1189	abi = "n64";
1190	break;
1191	case ArchSpec::eMIPSABI_N32:
1192	abi = "n32";
1193	break;
1194	case ArchSpec::eMIPSABI_O32:
1195	abi = "o32";
1196	break;
1197	default:
1198	break;
1199	}
1200	}
1201	return abi;
1202	}
1203
1204	/// Applies the given Fix-It hint to the given commit.
1205	static void ApplyFixIt(const FixItHint &fixit, clang::edit::Commit &commit) {
1206	// This is cobbed from clang::Rewrite::FixItRewriter.
1207	if (fixit.CodeToInsert.empty()) {
1208	if (fixit.InsertFromRange.isValid()) {
1209	commit.insertFromRange(loc: fixit.RemoveRange.getBegin(),
1210	range: fixit.InsertFromRange, /*afterToken=*/false,
1211	beforePreviousInsertions: fixit.BeforePreviousInsertions);
1212	return;
1213	}
1214	commit.remove(range: fixit.RemoveRange);
1215	return;
1216	}
1217	if (fixit.RemoveRange.isTokenRange() ||
1218	fixit.RemoveRange.getBegin() != fixit.RemoveRange.getEnd()) {
1219	commit.replace(range: fixit.RemoveRange, text: fixit.CodeToInsert);
1220	return;
1221	}
1222	commit.insert(loc: fixit.RemoveRange.getBegin(), text: fixit.CodeToInsert,
1223	/*afterToken=*/false, beforePreviousInsertions: fixit.BeforePreviousInsertions);
1224	}
1225
1226	bool ClangExpressionParser::RewriteExpression(
1227	DiagnosticManager &diagnostic_manager) {
1228	clang::SourceManager &source_manager = m_compiler->getSourceManager();
1229	clang::edit::EditedSource editor(source_manager, m_compiler->getLangOpts(),
1230	nullptr);
1231	clang::edit::Commit commit(editor);
1232	clang::Rewriter rewriter(source_manager, m_compiler->getLangOpts());
1233
1234	class RewritesReceiver : public edit::EditsReceiver {
1235	Rewriter &rewrite;
1236
1237	public:
1238	RewritesReceiver(Rewriter &in_rewrite) : rewrite(in_rewrite) {}
1239
1240	void insert(SourceLocation loc, StringRef text) override {
1241	rewrite.InsertText(Loc: loc, Str: text);
1242	}
1243	void replace(CharSourceRange range, StringRef text) override {
1244	rewrite.ReplaceText(Start: range.getBegin(), OrigLength: rewrite.getRangeSize(Range: range), NewStr: text);
1245	}
1246	};
1247
1248	RewritesReceiver rewrites_receiver(rewriter);
1249
1250	const DiagnosticList &diagnostics = diagnostic_manager.Diagnostics();
1251	size_t num_diags = diagnostics.size();
1252	if (num_diags == 0)
1253	return false;
1254
1255	for (const auto &diag : diagnostic_manager.Diagnostics()) {
1256	const auto *diagnostic = llvm::dyn_cast<ClangDiagnostic>(Val: diag.get());
1257	if (!diagnostic)
1258	continue;
1259	if (!diagnostic->HasFixIts())
1260	continue;
1261	for (const FixItHint &fixit : diagnostic->FixIts())
1262	ApplyFixIt(fixit, commit);
1263	}
1264
1265	// FIXME - do we want to try to propagate specific errors here?
1266	if (!commit.isCommitable())
1267	return false;
1268	else if (!editor.commit(commit))
1269	return false;
1270
1271	// Now play all the edits, and stash the result in the diagnostic manager.
1272	editor.applyRewrites(receiver&: rewrites_receiver);
1273	RewriteBuffer &main_file_buffer =
1274	rewriter.getEditBuffer(FID: source_manager.getMainFileID());
1275
1276	std::string fixed_expression;
1277	llvm::raw_string_ostream out_stream(fixed_expression);
1278
1279	main_file_buffer.write(Stream&: out_stream);
1280	out_stream.flush();
1281	diagnostic_manager.SetFixedExpression(fixed_expression);
1282
1283	return true;
1284	}
1285
1286	static bool FindFunctionInModule(ConstString &mangled_name,
1287	llvm::Module *module, const char *orig_name) {
1288	for (const auto &func : module->getFunctionList()) {
1289	const StringRef &name = func.getName();
1290	if (name.contains(Other: orig_name)) {
1291	mangled_name.SetString(name);
1292	return true;
1293	}
1294	}
1295
1296	return false;
1297	}
1298
1299	lldb_private::Status ClangExpressionParser::PrepareForExecution(
1300	lldb::addr_t &func_addr, lldb::addr_t &func_end,
1301	lldb::IRExecutionUnitSP &execution_unit_sp, ExecutionContext &exe_ctx,
1302	bool &can_interpret, ExecutionPolicy execution_policy) {
1303	func_addr = LLDB_INVALID_ADDRESS;
1304	func_end = LLDB_INVALID_ADDRESS;
1305	Log *log = GetLog(mask: LLDBLog::Expressions);
1306
1307	lldb_private::Status err;
1308
1309	std::unique_ptr<llvm::Module> llvm_module_up(
1310	m_code_generator->ReleaseModule());
1311
1312	if (!llvm_module_up) {
1313	err.SetErrorToGenericError();
1314	err.SetErrorString("IR doesn't contain a module");
1315	return err;
1316	}
1317
1318	ConstString function_name;
1319
1320	if (execution_policy != eExecutionPolicyTopLevel) {
1321	// Find the actual name of the function (it's often mangled somehow)
1322
1323	if (!FindFunctionInModule(mangled_name&: function_name, module: llvm_module_up.get(),
1324	orig_name: m_expr.FunctionName())) {
1325	err.SetErrorToGenericError();
1326	err.SetErrorStringWithFormat("Couldn't find %s() in the module",
1327	m_expr.FunctionName());
1328	return err;
1329	} else {
1330	LLDB_LOGF(log, "Found function %s for %s", function_name.AsCString(),
1331	m_expr.FunctionName());
1332	}
1333	}
1334
1335	SymbolContext sc;
1336
1337	if (lldb::StackFrameSP frame_sp = exe_ctx.GetFrameSP()) {
1338	sc = frame_sp->GetSymbolContext(resolve_scope: lldb::eSymbolContextEverything);
1339	} else if (lldb::TargetSP target_sp = exe_ctx.GetTargetSP()) {
1340	sc.target_sp = target_sp;
1341	}
1342
1343	LLVMUserExpression::IRPasses custom_passes;
1344	{
1345	auto lang = m_expr.Language();
1346	LLDB_LOGF(log, "%s - Current expression language is %s\n", __FUNCTION__,
1347	Language::GetNameForLanguageType(lang));
1348	lldb::ProcessSP process_sp = exe_ctx.GetProcessSP();
1349	if (process_sp && lang != lldb::eLanguageTypeUnknown) {
1350	auto runtime = process_sp->GetLanguageRuntime(language: lang);
1351	if (runtime)
1352	runtime->GetIRPasses(custom_passes);
1353	}
1354	}
1355
1356	if (custom_passes.EarlyPasses) {
1357	LLDB_LOGF(log,
1358	"%s - Running Early IR Passes from LanguageRuntime on "
1359	"expression module '%s'",
1360	__FUNCTION__, m_expr.FunctionName());
1361
1362	custom_passes.EarlyPasses->run(M&: *llvm_module_up);
1363	}
1364
1365	execution_unit_sp = std::make_shared<IRExecutionUnit>(
1366	args&: m_llvm_context, // handed off here
1367	args&: llvm_module_up, // handed off here
1368	args&: function_name, args: exe_ctx.GetTargetSP(), args&: sc,
1369	args&: m_compiler->getTargetOpts().Features);
1370
1371	ClangExpressionHelper *type_system_helper =
1372	dyn_cast<ClangExpressionHelper>(Val: m_expr.GetTypeSystemHelper());
1373	ClangExpressionDeclMap *decl_map =
1374	type_system_helper->DeclMap(); // result can be NULL
1375
1376	if (decl_map) {
1377	StreamString error_stream;
1378	IRForTarget ir_for_target(decl_map, m_expr.NeedsVariableResolution(),
1379	*execution_unit_sp, error_stream,
1380	function_name.AsCString());
1381
1382	if (!ir_for_target.runOnModule(llvm_module&: *execution_unit_sp->GetModule())) {
1383	err.SetErrorString(error_stream.GetString());
1384	return err;
1385	}
1386
1387	Process *process = exe_ctx.GetProcessPtr();
1388
1389	if (execution_policy != eExecutionPolicyAlways &&
1390	execution_policy != eExecutionPolicyTopLevel) {
1391	lldb_private::Status interpret_error;
1392
1393	bool interpret_function_calls =
1394	!process ? false : process->CanInterpretFunctionCalls();
1395	can_interpret = IRInterpreter::CanInterpret(
1396	module&: *execution_unit_sp->GetModule(), function&: *execution_unit_sp->GetFunction(),
1397	error&: interpret_error, support_function_calls: interpret_function_calls);
1398
1399	if (!can_interpret && execution_policy == eExecutionPolicyNever) {
1400	err.SetErrorStringWithFormat(
1401	"Can't evaluate the expression without a running target due to: %s",
1402	interpret_error.AsCString());
1403	return err;
1404	}
1405	}
1406
1407	if (!process && execution_policy == eExecutionPolicyAlways) {
1408	err.SetErrorString("Expression needed to run in the target, but the "
1409	"target can't be run");
1410	return err;
1411	}
1412
1413	if (!process && execution_policy == eExecutionPolicyTopLevel) {
1414	err.SetErrorString("Top-level code needs to be inserted into a runnable "
1415	"target, but the target can't be run");
1416	return err;
1417	}
1418
1419	if (execution_policy == eExecutionPolicyAlways ||
1420	(execution_policy != eExecutionPolicyTopLevel && !can_interpret)) {
1421	if (m_expr.NeedsValidation() && process) {
1422	if (!process->GetDynamicCheckers()) {
1423	ClangDynamicCheckerFunctions *dynamic_checkers =
1424	new ClangDynamicCheckerFunctions();
1425
1426	DiagnosticManager install_diags;
1427	if (Error Err = dynamic_checkers->Install(diagnostic_manager&: install_diags, exe_ctx)) {
1428	std::string ErrMsg = "couldn't install checkers: " + toString(E: std::move(Err));
1429	if (install_diags.Diagnostics().size())
1430	ErrMsg = ErrMsg + "\n" + install_diags.GetString().c_str();
1431	err.SetErrorString(ErrMsg);
1432	return err;
1433	}
1434
1435	process->SetDynamicCheckers(dynamic_checkers);
1436
1437	LLDB_LOGF(log, "== [ClangExpressionParser::PrepareForExecution] "
1438	"Finished installing dynamic checkers ==");
1439	}
1440
1441	if (auto *checker_funcs = llvm::dyn_cast<ClangDynamicCheckerFunctions>(
1442	Val: process->GetDynamicCheckers())) {
1443	IRDynamicChecks ir_dynamic_checks(*checker_funcs,
1444	function_name.AsCString());
1445
1446	llvm::Module *module = execution_unit_sp->GetModule();
1447	if (!module || !ir_dynamic_checks.runOnModule(M&: *module)) {
1448	err.SetErrorToGenericError();
1449	err.SetErrorString("Couldn't add dynamic checks to the expression");
1450	return err;
1451	}
1452
1453	if (custom_passes.LatePasses) {
1454	LLDB_LOGF(log,
1455	"%s - Running Late IR Passes from LanguageRuntime on "
1456	"expression module '%s'",
1457	__FUNCTION__, m_expr.FunctionName());
1458
1459	custom_passes.LatePasses->run(M&: *module);
1460	}
1461	}
1462	}
1463	}
1464
1465	if (execution_policy == eExecutionPolicyAlways ||
1466	execution_policy == eExecutionPolicyTopLevel || !can_interpret) {
1467	execution_unit_sp->GetRunnableInfo(error&: err, func_addr, func_end);
1468	}
1469	} else {
1470	execution_unit_sp->GetRunnableInfo(error&: err, func_addr, func_end);
1471	}
1472
1473	return err;
1474	}
1475
1476	lldb_private::Status ClangExpressionParser::RunStaticInitializers(
1477	lldb::IRExecutionUnitSP &execution_unit_sp, ExecutionContext &exe_ctx) {
1478	lldb_private::Status err;
1479
1480	lldbassert(execution_unit_sp.get());
1481	lldbassert(exe_ctx.HasThreadScope());
1482
1483	if (!execution_unit_sp.get()) {
1484	err.SetErrorString(
1485	"can't run static initializers for a NULL execution unit");
1486	return err;
1487	}
1488
1489	if (!exe_ctx.HasThreadScope()) {
1490	err.SetErrorString("can't run static initializers without a thread");
1491	return err;
1492	}
1493
1494	std::vector<lldb::addr_t> static_initializers;
1495
1496	execution_unit_sp->GetStaticInitializers(static_initializers);
1497
1498	for (lldb::addr_t static_initializer : static_initializers) {
1499	EvaluateExpressionOptions options;
1500
1501	lldb::ThreadPlanSP call_static_initializer(new ThreadPlanCallFunction(
1502	exe_ctx.GetThreadRef(), Address(static_initializer), CompilerType(),
1503	llvm::ArrayRef<lldb::addr_t>(), options));
1504
1505	DiagnosticManager execution_errors;
1506	lldb::ExpressionResults results =
1507	exe_ctx.GetThreadRef().GetProcess()->RunThreadPlan(
1508	exe_ctx, thread_plan_sp&: call_static_initializer, options, diagnostic_manager&: execution_errors);
1509
1510	if (results != lldb::eExpressionCompleted) {
1511	err.SetErrorStringWithFormat("couldn't run static initializer: %s",
1512	execution_errors.GetString().c_str());
1513	return err;
1514	}
1515	}
1516
1517	return err;
1518	}
1519