1//===-- ClangUserExpression.cpp ---------------------------------*- C++ -*-===//
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 "lldb/Host/Config.h"
10
11#include <stdio.h>
12#if HAVE_SYS_TYPES_H
13#include <sys/types.h>
14#endif
15
16#include <cstdlib>
17#include <map>
18#include <string>
19
20#include "ClangUserExpression.h"
21
22#include "ASTResultSynthesizer.h"
23#include "ClangDiagnostic.h"
24#include "ClangExpressionDeclMap.h"
25#include "ClangExpressionParser.h"
26#include "ClangModulesDeclVendor.h"
27#include "ClangPersistentVariables.h"
28#include "CppModuleConfiguration.h"
29
30#include "lldb/Core/Debugger.h"
31#include "lldb/Core/Module.h"
32#include "lldb/Core/StreamFile.h"
33#include "lldb/Core/ValueObjectConstResult.h"
34#include "lldb/Expression/ExpressionSourceCode.h"
35#include "lldb/Expression/IRExecutionUnit.h"
36#include "lldb/Expression/IRInterpreter.h"
37#include "lldb/Expression/Materializer.h"
38#include "lldb/Host/HostInfo.h"
39#include "lldb/Symbol/Block.h"
40#include "lldb/Symbol/ClangASTContext.h"
41#include "lldb/Symbol/ClangASTMetadata.h"
42#include "lldb/Symbol/CompileUnit.h"
43#include "lldb/Symbol/Function.h"
44#include "lldb/Symbol/ObjectFile.h"
45#include "lldb/Symbol/SymbolFile.h"
46#include "lldb/Symbol/SymbolVendor.h"
47#include "lldb/Symbol/Type.h"
48#include "lldb/Symbol/VariableList.h"
49#include "lldb/Target/ExecutionContext.h"
50#include "lldb/Target/Process.h"
51#include "lldb/Target/StackFrame.h"
52#include "lldb/Target/Target.h"
53#include "lldb/Target/ThreadPlan.h"
54#include "lldb/Target/ThreadPlanCallUserExpression.h"
55#include "lldb/Utility/ConstString.h"
56#include "lldb/Utility/Log.h"
57#include "lldb/Utility/StreamString.h"
58
59#include "clang/AST/DeclCXX.h"
60#include "clang/AST/DeclObjC.h"
61
62#include "llvm/ADT/ScopeExit.h"
63
64using namespace lldb_private;
65
66char ClangUserExpression::ID;
67
68ClangUserExpression::ClangUserExpression(
69    ExecutionContextScope &exe_scope, llvm::StringRef expr,
70    llvm::StringRef prefix, lldb::LanguageType language,
71    ResultType desired_type, const EvaluateExpressionOptions &options,
72    ValueObject *ctx_obj)
73    : LLVMUserExpression(exe_scope, expr, prefix, language, desired_type,
74                         options),
75      m_type_system_helper(*m_target_wp.lock(), options.GetExecutionPolicy() ==
76                                                    eExecutionPolicyTopLevel),
77      m_result_delegate(exe_scope.CalculateTarget()), m_ctx_obj(ctx_obj) {
78  switch (m_language) {
79  case lldb::eLanguageTypeC_plus_plus:
80    m_allow_cxx = true;
81    break;
82  case lldb::eLanguageTypeObjC:
83    m_allow_objc = true;
84    break;
85  case lldb::eLanguageTypeObjC_plus_plus:
86  default:
87    m_allow_cxx = true;
88    m_allow_objc = true;
89    break;
90  }
91}
92
93ClangUserExpression::~ClangUserExpression() {}
94
95void ClangUserExpression::ScanContext(ExecutionContext &exe_ctx, Status &err) {
96  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
97
98  LLDB_LOGF(log, "ClangUserExpression::ScanContext()");
99
100  m_target = exe_ctx.GetTargetPtr();
101
102  if (!(m_allow_cxx || m_allow_objc)) {
103    LLDB_LOGF(log, "  [CUE::SC] Settings inhibit C++ and Objective-C");
104    return;
105  }
106
107  StackFrame *frame = exe_ctx.GetFramePtr();
108  if (frame == nullptr) {
109    LLDB_LOGF(log, "  [CUE::SC] Null stack frame");
110    return;
111  }
112
113  SymbolContext sym_ctx = frame->GetSymbolContext(lldb::eSymbolContextFunction |
114                                                  lldb::eSymbolContextBlock);
115
116  if (!sym_ctx.function) {
117    LLDB_LOGF(log, "  [CUE::SC] Null function");
118    return;
119  }
120
121  // Find the block that defines the function represented by "sym_ctx"
122  Block *function_block = sym_ctx.GetFunctionBlock();
123
124  if (!function_block) {
125    LLDB_LOGF(log, "  [CUE::SC] Null function block");
126    return;
127  }
128
129  CompilerDeclContext decl_context = function_block->GetDeclContext();
130
131  if (!decl_context) {
132    LLDB_LOGF(log, "  [CUE::SC] Null decl context");
133    return;
134  }
135
136  if (m_ctx_obj) {
137    switch (m_ctx_obj->GetObjectRuntimeLanguage()) {
138    case lldb::eLanguageTypeC:
139    case lldb::eLanguageTypeC89:
140    case lldb::eLanguageTypeC99:
141    case lldb::eLanguageTypeC11:
142    case lldb::eLanguageTypeC_plus_plus:
143    case lldb::eLanguageTypeC_plus_plus_03:
144    case lldb::eLanguageTypeC_plus_plus_11:
145    case lldb::eLanguageTypeC_plus_plus_14:
146      m_in_cplusplus_method = true;
147      break;
148    case lldb::eLanguageTypeObjC:
149    case lldb::eLanguageTypeObjC_plus_plus:
150      m_in_objectivec_method = true;
151      break;
152    default:
153      break;
154    }
155    m_needs_object_ptr = true;
156  } else if (clang::CXXMethodDecl *method_decl =
157          ClangASTContext::DeclContextGetAsCXXMethodDecl(decl_context)) {
158    if (m_allow_cxx && method_decl->isInstance()) {
159      if (m_enforce_valid_object) {
160        lldb::VariableListSP variable_list_sp(
161            function_block->GetBlockVariableList(true));
162
163        const char *thisErrorString = "Stopped in a C++ method, but 'this' "
164                                      "isn't available; pretending we are in a "
165                                      "generic context";
166
167        if (!variable_list_sp) {
168          err.SetErrorString(thisErrorString);
169          return;
170        }
171
172        lldb::VariableSP this_var_sp(
173            variable_list_sp->FindVariable(ConstString("this")));
174
175        if (!this_var_sp || !this_var_sp->IsInScope(frame) ||
176            !this_var_sp->LocationIsValidForFrame(frame)) {
177          err.SetErrorString(thisErrorString);
178          return;
179        }
180      }
181
182      m_in_cplusplus_method = true;
183      m_needs_object_ptr = true;
184    }
185  } else if (clang::ObjCMethodDecl *method_decl =
186                 ClangASTContext::DeclContextGetAsObjCMethodDecl(
187                     decl_context)) {
188    if (m_allow_objc) {
189      if (m_enforce_valid_object) {
190        lldb::VariableListSP variable_list_sp(
191            function_block->GetBlockVariableList(true));
192
193        const char *selfErrorString = "Stopped in an Objective-C method, but "
194                                      "'self' isn't available; pretending we "
195                                      "are in a generic context";
196
197        if (!variable_list_sp) {
198          err.SetErrorString(selfErrorString);
199          return;
200        }
201
202        lldb::VariableSP self_variable_sp =
203            variable_list_sp->FindVariable(ConstString("self"));
204
205        if (!self_variable_sp || !self_variable_sp->IsInScope(frame) ||
206            !self_variable_sp->LocationIsValidForFrame(frame)) {
207          err.SetErrorString(selfErrorString);
208          return;
209        }
210      }
211
212      m_in_objectivec_method = true;
213      m_needs_object_ptr = true;
214
215      if (!method_decl->isInstanceMethod())
216        m_in_static_method = true;
217    }
218  } else if (clang::FunctionDecl *function_decl =
219                 ClangASTContext::DeclContextGetAsFunctionDecl(decl_context)) {
220    // We might also have a function that said in the debug information that it
221    // captured an object pointer.  The best way to deal with getting to the
222    // ivars at present is by pretending that this is a method of a class in
223    // whatever runtime the debug info says the object pointer belongs to.  Do
224    // that here.
225
226    ClangASTMetadata *metadata =
227        ClangASTContext::DeclContextGetMetaData(decl_context, function_decl);
228    if (metadata && metadata->HasObjectPtr()) {
229      lldb::LanguageType language = metadata->GetObjectPtrLanguage();
230      if (language == lldb::eLanguageTypeC_plus_plus) {
231        if (m_enforce_valid_object) {
232          lldb::VariableListSP variable_list_sp(
233              function_block->GetBlockVariableList(true));
234
235          const char *thisErrorString = "Stopped in a context claiming to "
236                                        "capture a C++ object pointer, but "
237                                        "'this' isn't available; pretending we "
238                                        "are in a generic context";
239
240          if (!variable_list_sp) {
241            err.SetErrorString(thisErrorString);
242            return;
243          }
244
245          lldb::VariableSP this_var_sp(
246              variable_list_sp->FindVariable(ConstString("this")));
247
248          if (!this_var_sp || !this_var_sp->IsInScope(frame) ||
249              !this_var_sp->LocationIsValidForFrame(frame)) {
250            err.SetErrorString(thisErrorString);
251            return;
252          }
253        }
254
255        m_in_cplusplus_method = true;
256        m_needs_object_ptr = true;
257      } else if (language == lldb::eLanguageTypeObjC) {
258        if (m_enforce_valid_object) {
259          lldb::VariableListSP variable_list_sp(
260              function_block->GetBlockVariableList(true));
261
262          const char *selfErrorString =
263              "Stopped in a context claiming to capture an Objective-C object "
264              "pointer, but 'self' isn't available; pretending we are in a "
265              "generic context";
266
267          if (!variable_list_sp) {
268            err.SetErrorString(selfErrorString);
269            return;
270          }
271
272          lldb::VariableSP self_variable_sp =
273              variable_list_sp->FindVariable(ConstString("self"));
274
275          if (!self_variable_sp || !self_variable_sp->IsInScope(frame) ||
276              !self_variable_sp->LocationIsValidForFrame(frame)) {
277            err.SetErrorString(selfErrorString);
278            return;
279          }
280
281          Type *self_type = self_variable_sp->GetType();
282
283          if (!self_type) {
284            err.SetErrorString(selfErrorString);
285            return;
286          }
287
288          CompilerType self_clang_type = self_type->GetForwardCompilerType();
289
290          if (!self_clang_type) {
291            err.SetErrorString(selfErrorString);
292            return;
293          }
294
295          if (ClangASTContext::IsObjCClassType(self_clang_type)) {
296            return;
297          } else if (ClangASTContext::IsObjCObjectPointerType(
298                         self_clang_type)) {
299            m_in_objectivec_method = true;
300            m_needs_object_ptr = true;
301          } else {
302            err.SetErrorString(selfErrorString);
303            return;
304          }
305        } else {
306          m_in_objectivec_method = true;
307          m_needs_object_ptr = true;
308        }
309      }
310    }
311  }
312}
313
314// This is a really nasty hack, meant to fix Objective-C expressions of the
315// form (int)[myArray count].  Right now, because the type information for
316// count is not available, [myArray count] returns id, which can't be directly
317// cast to int without causing a clang error.
318static void ApplyObjcCastHack(std::string &expr) {
319  const std::string from = "(int)[";
320  const std::string to = "(int)(long long)[";
321
322  size_t offset;
323
324  while ((offset = expr.find(from)) != expr.npos)
325    expr.replace(offset, from.size(), to);
326}
327
328bool ClangUserExpression::SetupPersistentState(DiagnosticManager &diagnostic_manager,
329                                 ExecutionContext &exe_ctx) {
330  if (Target *target = exe_ctx.GetTargetPtr()) {
331    if (PersistentExpressionState *persistent_state =
332            target->GetPersistentExpressionStateForLanguage(
333                lldb::eLanguageTypeC)) {
334      m_clang_state = llvm::cast<ClangPersistentVariables>(persistent_state);
335      m_result_delegate.RegisterPersistentState(persistent_state);
336    } else {
337      diagnostic_manager.PutString(
338          eDiagnosticSeverityError,
339          "couldn't start parsing (no persistent data)");
340      return false;
341    }
342  } else {
343    diagnostic_manager.PutString(eDiagnosticSeverityError,
344                                 "error: couldn't start parsing (no target)");
345    return false;
346  }
347  return true;
348}
349
350static void SetupDeclVendor(ExecutionContext &exe_ctx, Target *target) {
351  if (ClangModulesDeclVendor *decl_vendor =
352          target->GetClangModulesDeclVendor()) {
353    auto *persistent_state = llvm::cast<ClangPersistentVariables>(
354        target->GetPersistentExpressionStateForLanguage(lldb::eLanguageTypeC));
355    if (!persistent_state)
356      return;
357    const ClangModulesDeclVendor::ModuleVector &hand_imported_modules =
358        persistent_state->GetHandLoadedClangModules();
359    ClangModulesDeclVendor::ModuleVector modules_for_macros;
360
361    for (ClangModulesDeclVendor::ModuleID module : hand_imported_modules) {
362      modules_for_macros.push_back(module);
363    }
364
365    if (target->GetEnableAutoImportClangModules()) {
366      if (StackFrame *frame = exe_ctx.GetFramePtr()) {
367        if (Block *block = frame->GetFrameBlock()) {
368          SymbolContext sc;
369
370          block->CalculateSymbolContext(&sc);
371
372          if (sc.comp_unit) {
373            StreamString error_stream;
374
375            decl_vendor->AddModulesForCompileUnit(
376                *sc.comp_unit, modules_for_macros, error_stream);
377          }
378        }
379      }
380    }
381  }
382}
383
384void ClangUserExpression::UpdateLanguageForExpr() {
385  m_expr_lang = lldb::LanguageType::eLanguageTypeUnknown;
386  if (m_options.GetExecutionPolicy() == eExecutionPolicyTopLevel)
387    return;
388  if (m_in_cplusplus_method)
389    m_expr_lang = lldb::eLanguageTypeC_plus_plus;
390  else if (m_in_objectivec_method)
391    m_expr_lang = lldb::eLanguageTypeObjC;
392  else
393    m_expr_lang = lldb::eLanguageTypeC;
394}
395
396void ClangUserExpression::CreateSourceCode(
397    DiagnosticManager &diagnostic_manager, ExecutionContext &exe_ctx,
398    std::vector<std::string> modules_to_import, bool for_completion) {
399
400  m_filename = m_clang_state->GetNextExprFileName();
401  std::string prefix = m_expr_prefix;
402
403  if (m_options.GetExecutionPolicy() == eExecutionPolicyTopLevel) {
404    m_transformed_text = m_expr_text;
405  } else {
406    m_source_code.reset(ClangExpressionSourceCode::CreateWrapped(
407        m_filename, prefix.c_str(), m_expr_text.c_str()));
408
409    if (!m_source_code->GetText(m_transformed_text, m_expr_lang,
410                                m_in_static_method, exe_ctx, !m_ctx_obj,
411                                for_completion, modules_to_import)) {
412      diagnostic_manager.PutString(eDiagnosticSeverityError,
413                                   "couldn't construct expression body");
414      return;
415    }
416
417    // Find and store the start position of the original code inside the
418    // transformed code. We need this later for the code completion.
419    std::size_t original_start;
420    std::size_t original_end;
421    bool found_bounds = m_source_code->GetOriginalBodyBounds(
422        m_transformed_text, m_expr_lang, original_start, original_end);
423    if (found_bounds)
424      m_user_expression_start_pos = original_start;
425  }
426}
427
428static bool SupportsCxxModuleImport(lldb::LanguageType language) {
429  switch (language) {
430  case lldb::eLanguageTypeC_plus_plus:
431  case lldb::eLanguageTypeC_plus_plus_03:
432  case lldb::eLanguageTypeC_plus_plus_11:
433  case lldb::eLanguageTypeC_plus_plus_14:
434  case lldb::eLanguageTypeObjC_plus_plus:
435    return true;
436  default:
437    return false;
438  }
439}
440
441/// Utility method that puts a message into the expression log and
442/// returns an invalid module configuration.
443static CppModuleConfiguration LogConfigError(const std::string &msg) {
444  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
445  LLDB_LOG(log, "[C++ module config] {0}", msg);
446  return CppModuleConfiguration();
447}
448
449CppModuleConfiguration GetModuleConfig(lldb::LanguageType language,
450                                       ExecutionContext &exe_ctx) {
451  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
452
453  // Don't do anything if this is not a C++ module configuration.
454  if (!SupportsCxxModuleImport(language))
455    return LogConfigError("Language doesn't support C++ modules");
456
457  Target *target = exe_ctx.GetTargetPtr();
458  if (!target)
459    return LogConfigError("No target");
460
461  if (!target->GetEnableImportStdModule())
462    return LogConfigError("Importing std module not enabled in settings");
463
464  StackFrame *frame = exe_ctx.GetFramePtr();
465  if (!frame)
466    return LogConfigError("No frame");
467
468  Block *block = frame->GetFrameBlock();
469  if (!block)
470    return LogConfigError("No block");
471
472  SymbolContext sc;
473  block->CalculateSymbolContext(&sc);
474  if (!sc.comp_unit)
475    return LogConfigError("Couldn't calculate symbol context");
476
477  // Build a list of files we need to analyze to build the configuration.
478  FileSpecList files;
479  for (const FileSpec &f : sc.comp_unit->GetSupportFiles())
480    files.AppendIfUnique(f);
481  // We also need to look at external modules in the case of -gmodules as they
482  // contain the support files for libc++ and the C library.
483  llvm::DenseSet<SymbolFile *> visited_symbol_files;
484  sc.comp_unit->ForEachExternalModule(
485      visited_symbol_files, [&files](Module &module) {
486        for (std::size_t i = 0; i < module.GetNumCompileUnits(); ++i) {
487          const FileSpecList &support_files =
488              module.GetCompileUnitAtIndex(i)->GetSupportFiles();
489          for (const FileSpec &f : support_files) {
490            files.AppendIfUnique(f);
491          }
492        }
493        return false;
494      });
495
496  LLDB_LOG(log, "[C++ module config] Found {0} support files to analyze",
497           files.GetSize());
498  if (log && log->GetVerbose()) {
499    for (const FileSpec &f : files)
500      LLDB_LOGV(log, "[C++ module config] Analyzing support file: {0}",
501                f.GetPath());
502  }
503
504  // Try to create a configuration from the files. If there is no valid
505  // configuration possible with the files, this just returns an invalid
506  // configuration.
507  return CppModuleConfiguration(files);
508}
509
510bool ClangUserExpression::PrepareForParsing(
511    DiagnosticManager &diagnostic_manager, ExecutionContext &exe_ctx,
512    bool for_completion) {
513  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
514
515  InstallContext(exe_ctx);
516
517  if (!SetupPersistentState(diagnostic_manager, exe_ctx))
518    return false;
519
520  Status err;
521  ScanContext(exe_ctx, err);
522
523  if (!err.Success()) {
524    diagnostic_manager.PutString(eDiagnosticSeverityWarning, err.AsCString());
525  }
526
527  ////////////////////////////////////
528  // Generate the expression
529  //
530
531  ApplyObjcCastHack(m_expr_text);
532
533  SetupDeclVendor(exe_ctx, m_target);
534
535  CppModuleConfiguration module_config = GetModuleConfig(m_language, exe_ctx);
536  llvm::ArrayRef<std::string> imported_modules =
537      module_config.GetImportedModules();
538  m_imported_cpp_modules = !imported_modules.empty();
539  m_include_directories = module_config.GetIncludeDirs();
540
541  LLDB_LOG(log, "List of imported modules in expression: {0}",
542           llvm::make_range(imported_modules.begin(), imported_modules.end()));
543  LLDB_LOG(log, "List of include directories gathered for modules: {0}",
544           llvm::make_range(m_include_directories.begin(),
545                            m_include_directories.end()));
546
547  UpdateLanguageForExpr();
548  CreateSourceCode(diagnostic_manager, exe_ctx, imported_modules,
549                   for_completion);
550  return true;
551}
552
553bool ClangUserExpression::Parse(DiagnosticManager &diagnostic_manager,
554                                ExecutionContext &exe_ctx,
555                                lldb_private::ExecutionPolicy execution_policy,
556                                bool keep_result_in_memory,
557                                bool generate_debug_info) {
558  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
559
560  if (!PrepareForParsing(diagnostic_manager, exe_ctx, /*for_completion*/ false))
561    return false;
562
563  LLDB_LOGF(log, "Parsing the following code:\n%s", m_transformed_text.c_str());
564
565  ////////////////////////////////////
566  // Set up the target and compiler
567  //
568
569  Target *target = exe_ctx.GetTargetPtr();
570
571  if (!target) {
572    diagnostic_manager.PutString(eDiagnosticSeverityError, "invalid target");
573    return false;
574  }
575
576  //////////////////////////
577  // Parse the expression
578  //
579
580  m_materializer_up.reset(new Materializer());
581
582  ResetDeclMap(exe_ctx, m_result_delegate, keep_result_in_memory);
583
584  auto on_exit = llvm::make_scope_exit([this]() { ResetDeclMap(); });
585
586  if (!DeclMap()->WillParse(exe_ctx, GetMaterializer())) {
587    diagnostic_manager.PutString(
588        eDiagnosticSeverityError,
589        "current process state is unsuitable for expression parsing");
590    return false;
591  }
592
593  if (m_options.GetExecutionPolicy() == eExecutionPolicyTopLevel) {
594    DeclMap()->SetLookupsEnabled(true);
595  }
596
597  Process *process = exe_ctx.GetProcessPtr();
598  ExecutionContextScope *exe_scope = process;
599
600  if (!exe_scope)
601    exe_scope = exe_ctx.GetTargetPtr();
602
603  // We use a shared pointer here so we can use the original parser - if it
604  // succeeds or the rewrite parser we might make if it fails.  But the
605  // parser_sp will never be empty.
606
607  ClangExpressionParser parser(exe_scope, *this, generate_debug_info,
608                               m_include_directories, m_filename);
609
610  unsigned num_errors = parser.Parse(diagnostic_manager);
611
612  // Check here for FixItHints.  If there are any try to apply the fixits and
613  // set the fixed text in m_fixed_text before returning an error.
614  if (num_errors) {
615    if (diagnostic_manager.HasFixIts()) {
616      if (parser.RewriteExpression(diagnostic_manager)) {
617        size_t fixed_start;
618        size_t fixed_end;
619        const std::string &fixed_expression =
620            diagnostic_manager.GetFixedExpression();
621        // Retrieve the original expression in case we don't have a top level
622        // expression (which has no surrounding source code).
623        if (m_source_code &&
624            m_source_code->GetOriginalBodyBounds(fixed_expression, m_expr_lang,
625                                                 fixed_start, fixed_end))
626          m_fixed_text =
627              fixed_expression.substr(fixed_start, fixed_end - fixed_start);
628      }
629    }
630    return false;
631  }
632
633  //////////////////////////////////////////////////////////////////////////////
634  // Prepare the output of the parser for execution, evaluating it statically
635  // if possible
636  //
637
638  {
639    Status jit_error = parser.PrepareForExecution(
640        m_jit_start_addr, m_jit_end_addr, m_execution_unit_sp, exe_ctx,
641        m_can_interpret, execution_policy);
642
643    if (!jit_error.Success()) {
644      const char *error_cstr = jit_error.AsCString();
645      if (error_cstr && error_cstr[0])
646        diagnostic_manager.PutString(eDiagnosticSeverityError, error_cstr);
647      else
648        diagnostic_manager.PutString(eDiagnosticSeverityError,
649                                     "expression can't be interpreted or run");
650      return false;
651    }
652  }
653
654  if (exe_ctx.GetProcessPtr() && execution_policy == eExecutionPolicyTopLevel) {
655    Status static_init_error =
656        parser.RunStaticInitializers(m_execution_unit_sp, exe_ctx);
657
658    if (!static_init_error.Success()) {
659      const char *error_cstr = static_init_error.AsCString();
660      if (error_cstr && error_cstr[0])
661        diagnostic_manager.Printf(eDiagnosticSeverityError,
662                                  "couldn't run static initializers: %s\n",
663                                  error_cstr);
664      else
665        diagnostic_manager.PutString(eDiagnosticSeverityError,
666                                     "couldn't run static initializers\n");
667      return false;
668    }
669  }
670
671  if (m_execution_unit_sp) {
672    bool register_execution_unit = false;
673
674    if (m_options.GetExecutionPolicy() == eExecutionPolicyTopLevel) {
675      register_execution_unit = true;
676    }
677
678    // If there is more than one external function in the execution unit, it
679    // needs to keep living even if it's not top level, because the result
680    // could refer to that function.
681
682    if (m_execution_unit_sp->GetJittedFunctions().size() > 1) {
683      register_execution_unit = true;
684    }
685
686    if (register_execution_unit) {
687      if (auto *persistent_state =
688              exe_ctx.GetTargetPtr()->GetPersistentExpressionStateForLanguage(
689                  m_language))
690        persistent_state->RegisterExecutionUnit(m_execution_unit_sp);
691    }
692  }
693
694  if (generate_debug_info) {
695    lldb::ModuleSP jit_module_sp(m_execution_unit_sp->GetJITModule());
696
697    if (jit_module_sp) {
698      ConstString const_func_name(FunctionName());
699      FileSpec jit_file;
700      jit_file.GetFilename() = const_func_name;
701      jit_module_sp->SetFileSpecAndObjectName(jit_file, ConstString());
702      m_jit_module_wp = jit_module_sp;
703      target->GetImages().Append(jit_module_sp);
704    }
705  }
706
707  if (process && m_jit_start_addr != LLDB_INVALID_ADDRESS)
708    m_jit_process_wp = lldb::ProcessWP(process->shared_from_this());
709  return true;
710}
711
712/// Converts an absolute position inside a given code string into
713/// a column/line pair.
714///
715/// \param[in] abs_pos
716///     A absolute position in the code string that we want to convert
717///     to a column/line pair.
718///
719/// \param[in] code
720///     A multi-line string usually representing source code.
721///
722/// \param[out] line
723///     The line in the code that contains the given absolute position.
724///     The first line in the string is indexed as 1.
725///
726/// \param[out] column
727///     The column in the line that contains the absolute position.
728///     The first character in a line is indexed as 0.
729static void AbsPosToLineColumnPos(size_t abs_pos, llvm::StringRef code,
730                                  unsigned &line, unsigned &column) {
731  // Reset to code position to beginning of the file.
732  line = 0;
733  column = 0;
734
735  assert(abs_pos <= code.size() && "Absolute position outside code string?");
736
737  // We have to walk up to the position and count lines/columns.
738  for (std::size_t i = 0; i < abs_pos; ++i) {
739    // If we hit a line break, we go back to column 0 and enter a new line.
740    // We only handle \n because that's what we internally use to make new
741    // lines for our temporary code strings.
742    if (code[i] == '\n') {
743      ++line;
744      column = 0;
745      continue;
746    }
747    ++column;
748  }
749}
750
751bool ClangUserExpression::Complete(ExecutionContext &exe_ctx,
752                                   CompletionRequest &request,
753                                   unsigned complete_pos) {
754  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
755
756  // We don't want any visible feedback when completing an expression. Mostly
757  // because the results we get from an incomplete invocation are probably not
758  // correct.
759  DiagnosticManager diagnostic_manager;
760
761  if (!PrepareForParsing(diagnostic_manager, exe_ctx, /*for_completion*/ true))
762    return false;
763
764  LLDB_LOGF(log, "Parsing the following code:\n%s", m_transformed_text.c_str());
765
766  //////////////////////////
767  // Parse the expression
768  //
769
770  m_materializer_up.reset(new Materializer());
771
772  ResetDeclMap(exe_ctx, m_result_delegate, /*keep result in memory*/ true);
773
774  auto on_exit = llvm::make_scope_exit([this]() { ResetDeclMap(); });
775
776  if (!DeclMap()->WillParse(exe_ctx, GetMaterializer())) {
777    diagnostic_manager.PutString(
778        eDiagnosticSeverityError,
779        "current process state is unsuitable for expression parsing");
780
781    return false;
782  }
783
784  if (m_options.GetExecutionPolicy() == eExecutionPolicyTopLevel) {
785    DeclMap()->SetLookupsEnabled(true);
786  }
787
788  Process *process = exe_ctx.GetProcessPtr();
789  ExecutionContextScope *exe_scope = process;
790
791  if (!exe_scope)
792    exe_scope = exe_ctx.GetTargetPtr();
793
794  ClangExpressionParser parser(exe_scope, *this, false);
795
796  // We have to find the source code location where the user text is inside
797  // the transformed expression code. When creating the transformed text, we
798  // already stored the absolute position in the m_transformed_text string. The
799  // only thing left to do is to transform it into the line:column format that
800  // Clang expects.
801
802  // The line and column of the user expression inside the transformed source
803  // code.
804  unsigned user_expr_line, user_expr_column;
805  if (m_user_expression_start_pos.hasValue())
806    AbsPosToLineColumnPos(*m_user_expression_start_pos, m_transformed_text,
807                          user_expr_line, user_expr_column);
808  else
809    return false;
810
811  // The actual column where we have to complete is the start column of the
812  // user expression + the offset inside the user code that we were given.
813  const unsigned completion_column = user_expr_column + complete_pos;
814  parser.Complete(request, user_expr_line, completion_column, complete_pos);
815
816  return true;
817}
818
819bool ClangUserExpression::AddArguments(ExecutionContext &exe_ctx,
820                                       std::vector<lldb::addr_t> &args,
821                                       lldb::addr_t struct_address,
822                                       DiagnosticManager &diagnostic_manager) {
823  lldb::addr_t object_ptr = LLDB_INVALID_ADDRESS;
824  lldb::addr_t cmd_ptr = LLDB_INVALID_ADDRESS;
825
826  if (m_needs_object_ptr) {
827    lldb::StackFrameSP frame_sp = exe_ctx.GetFrameSP();
828    if (!frame_sp)
829      return true;
830
831    ConstString object_name;
832
833    if (m_in_cplusplus_method) {
834      object_name.SetCString("this");
835    } else if (m_in_objectivec_method) {
836      object_name.SetCString("self");
837    } else {
838      diagnostic_manager.PutString(
839          eDiagnosticSeverityError,
840          "need object pointer but don't know the language");
841      return false;
842    }
843
844    Status object_ptr_error;
845
846    if (m_ctx_obj) {
847      AddressType address_type;
848      object_ptr = m_ctx_obj->GetAddressOf(false, &address_type);
849      if (object_ptr == LLDB_INVALID_ADDRESS ||
850          address_type != eAddressTypeLoad)
851        object_ptr_error.SetErrorString("Can't get context object's "
852                                        "debuggee address");
853    } else
854      object_ptr = GetObjectPointer(frame_sp, object_name, object_ptr_error);
855
856    if (!object_ptr_error.Success()) {
857      exe_ctx.GetTargetRef().GetDebugger().GetAsyncOutputStream()->Printf(
858          "warning: `%s' is not accessible (substituting 0)\n",
859          object_name.AsCString());
860      object_ptr = 0;
861    }
862
863    if (m_in_objectivec_method) {
864      ConstString cmd_name("_cmd");
865
866      cmd_ptr = GetObjectPointer(frame_sp, cmd_name, object_ptr_error);
867
868      if (!object_ptr_error.Success()) {
869        diagnostic_manager.Printf(
870            eDiagnosticSeverityWarning,
871            "couldn't get cmd pointer (substituting NULL): %s",
872            object_ptr_error.AsCString());
873        cmd_ptr = 0;
874      }
875    }
876
877    args.push_back(object_ptr);
878
879    if (m_in_objectivec_method)
880      args.push_back(cmd_ptr);
881
882    args.push_back(struct_address);
883  } else {
884    args.push_back(struct_address);
885  }
886  return true;
887}
888
889lldb::ExpressionVariableSP ClangUserExpression::GetResultAfterDematerialization(
890    ExecutionContextScope *exe_scope) {
891  return m_result_delegate.GetVariable();
892}
893
894void ClangUserExpression::ClangUserExpressionHelper::ResetDeclMap(
895    ExecutionContext &exe_ctx,
896    Materializer::PersistentVariableDelegate &delegate,
897    bool keep_result_in_memory,
898    ValueObject *ctx_obj) {
899  m_expr_decl_map_up.reset(new ClangExpressionDeclMap(
900      keep_result_in_memory, &delegate, exe_ctx.GetTargetSP(),
901      exe_ctx.GetTargetRef().GetClangASTImporter(), ctx_obj));
902}
903
904clang::ASTConsumer *
905ClangUserExpression::ClangUserExpressionHelper::ASTTransformer(
906    clang::ASTConsumer *passthrough) {
907  m_result_synthesizer_up.reset(
908      new ASTResultSynthesizer(passthrough, m_top_level, m_target));
909
910  return m_result_synthesizer_up.get();
911}
912
913void ClangUserExpression::ClangUserExpressionHelper::CommitPersistentDecls() {
914  if (m_result_synthesizer_up) {
915    m_result_synthesizer_up->CommitPersistentDecls();
916  }
917}
918
919ConstString ClangUserExpression::ResultDelegate::GetName() {
920  auto prefix = m_persistent_state->GetPersistentVariablePrefix();
921  return m_persistent_state->GetNextPersistentVariableName(*m_target_sp,
922                                                           prefix);
923}
924
925void ClangUserExpression::ResultDelegate::DidDematerialize(
926    lldb::ExpressionVariableSP &variable) {
927  m_variable = variable;
928}
929
930void ClangUserExpression::ResultDelegate::RegisterPersistentState(
931    PersistentExpressionState *persistent_state) {
932  m_persistent_state = persistent_state;
933}
934
935lldb::ExpressionVariableSP &ClangUserExpression::ResultDelegate::GetVariable() {
936  return m_variable;
937}
938