1//===-- ClangUserExpression.cpp ---------------------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10// C Includes
11#include <stdio.h>
12#if HAVE_SYS_TYPES_H
13#  include <sys/types.h>
14#endif
15
16// C++ Includes
17#include <cstdlib>
18#include <string>
19#include <map>
20
21#include "lldb/Core/ConstString.h"
22#include "lldb/Core/Log.h"
23#include "lldb/Core/StreamFile.h"
24#include "lldb/Core/StreamString.h"
25#include "lldb/Core/ValueObjectConstResult.h"
26#include "lldb/Expression/ASTResultSynthesizer.h"
27#include "lldb/Expression/ClangExpressionDeclMap.h"
28#include "lldb/Expression/ClangExpressionParser.h"
29#include "lldb/Expression/ClangFunction.h"
30#include "lldb/Expression/ClangUserExpression.h"
31#include "lldb/Expression/ExpressionSourceCode.h"
32#include "lldb/Expression/IRExecutionUnit.h"
33#include "lldb/Expression/IRInterpreter.h"
34#include "lldb/Expression/Materializer.h"
35#include "lldb/Host/Host.h"
36#include "lldb/Symbol/Block.h"
37#include "lldb/Symbol/ClangASTContext.h"
38#include "lldb/Symbol/Function.h"
39#include "lldb/Symbol/Type.h"
40#include "lldb/Symbol/ClangExternalASTSourceCommon.h"
41#include "lldb/Symbol/VariableList.h"
42#include "lldb/Target/ExecutionContext.h"
43#include "lldb/Target/Process.h"
44#include "lldb/Target/StackFrame.h"
45#include "lldb/Target/Target.h"
46#include "lldb/Target/ThreadPlan.h"
47#include "lldb/Target/ThreadPlanCallUserExpression.h"
48
49#include "clang/AST/DeclCXX.h"
50#include "clang/AST/DeclObjC.h"
51
52using namespace lldb_private;
53
54ClangUserExpression::ClangUserExpression (const char *expr,
55                                          const char *expr_prefix,
56                                          lldb::LanguageType language,
57                                          ResultType desired_type) :
58    ClangExpression (),
59    m_stack_frame_bottom (LLDB_INVALID_ADDRESS),
60    m_stack_frame_top (LLDB_INVALID_ADDRESS),
61    m_expr_text (expr),
62    m_expr_prefix (expr_prefix ? expr_prefix : ""),
63    m_language (language),
64    m_transformed_text (),
65    m_desired_type (desired_type),
66    m_enforce_valid_object (true),
67    m_cplusplus (false),
68    m_objectivec (false),
69    m_static_method(false),
70    m_needs_object_ptr (false),
71    m_const_object (false),
72    m_target (NULL),
73    m_can_interpret (false),
74    m_materialized_address (LLDB_INVALID_ADDRESS)
75{
76    switch (m_language)
77    {
78    case lldb::eLanguageTypeC_plus_plus:
79        m_allow_cxx = true;
80        break;
81    case lldb::eLanguageTypeObjC:
82        m_allow_objc = true;
83        break;
84    case lldb::eLanguageTypeObjC_plus_plus:
85    default:
86        m_allow_cxx = true;
87        m_allow_objc = true;
88        break;
89    }
90}
91
92ClangUserExpression::~ClangUserExpression ()
93{
94}
95
96clang::ASTConsumer *
97ClangUserExpression::ASTTransformer (clang::ASTConsumer *passthrough)
98{
99    m_result_synthesizer.reset(new ASTResultSynthesizer(passthrough,
100                                                        *m_target));
101
102    return m_result_synthesizer.get();
103}
104
105void
106ClangUserExpression::ScanContext(ExecutionContext &exe_ctx, Error &err)
107{
108    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
109
110    if (log)
111        log->Printf("ClangUserExpression::ScanContext()");
112
113    m_target = exe_ctx.GetTargetPtr();
114
115    if (!(m_allow_cxx || m_allow_objc))
116    {
117        if (log)
118            log->Printf("  [CUE::SC] Settings inhibit C++ and Objective-C");
119        return;
120    }
121
122    StackFrame *frame = exe_ctx.GetFramePtr();
123    if (frame == NULL)
124    {
125        if (log)
126            log->Printf("  [CUE::SC] Null stack frame");
127        return;
128    }
129
130    SymbolContext sym_ctx = frame->GetSymbolContext(lldb::eSymbolContextFunction | lldb::eSymbolContextBlock);
131
132    if (!sym_ctx.function)
133    {
134        if (log)
135            log->Printf("  [CUE::SC] Null function");
136        return;
137    }
138
139    // Find the block that defines the function represented by "sym_ctx"
140    Block *function_block = sym_ctx.GetFunctionBlock();
141
142    if (!function_block)
143    {
144        if (log)
145            log->Printf("  [CUE::SC] Null function block");
146        return;
147    }
148
149    clang::DeclContext *decl_context = function_block->GetClangDeclContext();
150
151    if (!decl_context)
152    {
153        if (log)
154            log->Printf("  [CUE::SC] Null decl context");
155        return;
156    }
157
158    if (clang::CXXMethodDecl *method_decl = llvm::dyn_cast<clang::CXXMethodDecl>(decl_context))
159    {
160        if (m_allow_cxx && method_decl->isInstance())
161        {
162            if (m_enforce_valid_object)
163            {
164                lldb::VariableListSP variable_list_sp (function_block->GetBlockVariableList (true));
165
166                const char *thisErrorString = "Stopped in a C++ method, but 'this' isn't available; pretending we are in a generic context";
167
168                if (!variable_list_sp)
169                {
170                    err.SetErrorString(thisErrorString);
171                    return;
172                }
173
174                lldb::VariableSP this_var_sp (variable_list_sp->FindVariable(ConstString("this")));
175
176                if (!this_var_sp ||
177                    !this_var_sp->IsInScope(frame) ||
178                    !this_var_sp->LocationIsValidForFrame (frame))
179                {
180                    err.SetErrorString(thisErrorString);
181                    return;
182                }
183            }
184
185            m_cplusplus = true;
186            m_needs_object_ptr = true;
187        }
188    }
189    else if (clang::ObjCMethodDecl *method_decl = llvm::dyn_cast<clang::ObjCMethodDecl>(decl_context))
190    {
191        if (m_allow_objc)
192        {
193            if (m_enforce_valid_object)
194            {
195                lldb::VariableListSP variable_list_sp (function_block->GetBlockVariableList (true));
196
197                const char *selfErrorString = "Stopped in an Objective-C method, but 'self' isn't available; pretending we are in a generic context";
198
199                if (!variable_list_sp)
200                {
201                    err.SetErrorString(selfErrorString);
202                    return;
203                }
204
205                lldb::VariableSP self_variable_sp = variable_list_sp->FindVariable(ConstString("self"));
206
207                if (!self_variable_sp ||
208                    !self_variable_sp->IsInScope(frame) ||
209                    !self_variable_sp->LocationIsValidForFrame (frame))
210                {
211                    err.SetErrorString(selfErrorString);
212                    return;
213                }
214            }
215
216            m_objectivec = true;
217            m_needs_object_ptr = true;
218
219            if (!method_decl->isInstanceMethod())
220                m_static_method = true;
221        }
222    }
223    else if (clang::FunctionDecl *function_decl = llvm::dyn_cast<clang::FunctionDecl>(decl_context))
224    {
225        // We might also have a function that said in the debug information that it captured an
226        // object pointer.  The best way to deal with getting to the ivars at present it by pretending
227        // that this is a method of a class in whatever runtime the debug info says the object pointer
228        // belongs to.  Do that here.
229
230        ClangASTMetadata *metadata = ClangASTContext::GetMetadata (&decl_context->getParentASTContext(), function_decl);
231        if (metadata && metadata->HasObjectPtr())
232        {
233            lldb::LanguageType language = metadata->GetObjectPtrLanguage();
234            if (language == lldb::eLanguageTypeC_plus_plus)
235            {
236                if (m_enforce_valid_object)
237                {
238                    lldb::VariableListSP variable_list_sp (function_block->GetBlockVariableList (true));
239
240                    const char *thisErrorString = "Stopped in a context claiming to capture a C++ object pointer, but 'this' isn't available; pretending we are in a generic context";
241
242                    if (!variable_list_sp)
243                    {
244                        err.SetErrorString(thisErrorString);
245                        return;
246                    }
247
248                    lldb::VariableSP this_var_sp (variable_list_sp->FindVariable(ConstString("this")));
249
250                    if (!this_var_sp ||
251                        !this_var_sp->IsInScope(frame) ||
252                        !this_var_sp->LocationIsValidForFrame (frame))
253                    {
254                        err.SetErrorString(thisErrorString);
255                        return;
256                    }
257                }
258
259                m_cplusplus = true;
260                m_needs_object_ptr = true;
261            }
262            else if (language == lldb::eLanguageTypeObjC)
263            {
264                if (m_enforce_valid_object)
265                {
266                    lldb::VariableListSP variable_list_sp (function_block->GetBlockVariableList (true));
267
268                    const char *selfErrorString = "Stopped in a context claiming to capture an Objective-C object pointer, but 'self' isn't available; pretending we are in a generic context";
269
270                    if (!variable_list_sp)
271                    {
272                        err.SetErrorString(selfErrorString);
273                        return;
274                    }
275
276                    lldb::VariableSP self_variable_sp = variable_list_sp->FindVariable(ConstString("self"));
277
278                    if (!self_variable_sp ||
279                        !self_variable_sp->IsInScope(frame) ||
280                        !self_variable_sp->LocationIsValidForFrame (frame))
281                    {
282                        err.SetErrorString(selfErrorString);
283                        return;
284                    }
285
286                    Type *self_type = self_variable_sp->GetType();
287
288                    if (!self_type)
289                    {
290                        err.SetErrorString(selfErrorString);
291                        return;
292                    }
293
294                    ClangASTType self_clang_type = self_type->GetClangForwardType();
295
296                    if (!self_clang_type)
297                    {
298                        err.SetErrorString(selfErrorString);
299                        return;
300                    }
301
302                    if (self_clang_type.IsObjCClassType())
303                    {
304                        return;
305                    }
306                    else if (self_clang_type.IsObjCObjectPointerType())
307                    {
308                        m_objectivec = true;
309                        m_needs_object_ptr = true;
310                    }
311                    else
312                    {
313                        err.SetErrorString(selfErrorString);
314                        return;
315                    }
316                }
317                else
318                {
319                    m_objectivec = true;
320                    m_needs_object_ptr = true;
321                }
322            }
323        }
324    }
325}
326
327void
328ClangUserExpression::InstallContext (ExecutionContext &exe_ctx)
329{
330    m_process_wp = exe_ctx.GetProcessSP();
331
332    lldb::StackFrameSP frame_sp = exe_ctx.GetFrameSP();
333
334    if (frame_sp)
335        m_address = frame_sp->GetFrameCodeAddress();
336}
337
338bool
339ClangUserExpression::LockAndCheckContext (ExecutionContext &exe_ctx,
340                                          lldb::TargetSP &target_sp,
341                                          lldb::ProcessSP &process_sp,
342                                          lldb::StackFrameSP &frame_sp)
343{
344    lldb::ProcessSP expected_process_sp = m_process_wp.lock();
345    process_sp = exe_ctx.GetProcessSP();
346
347    if (process_sp != expected_process_sp)
348        return false;
349
350    process_sp = exe_ctx.GetProcessSP();
351    target_sp = exe_ctx.GetTargetSP();
352    frame_sp = exe_ctx.GetFrameSP();
353
354    if (m_address.IsValid())
355    {
356        if (!frame_sp)
357            return false;
358        else
359            return (0 == Address::CompareLoadAddress(m_address, frame_sp->GetFrameCodeAddress(), target_sp.get()));
360    }
361
362    return true;
363}
364
365bool
366ClangUserExpression::MatchesContext (ExecutionContext &exe_ctx)
367{
368    lldb::TargetSP target_sp;
369    lldb::ProcessSP process_sp;
370    lldb::StackFrameSP frame_sp;
371
372    return LockAndCheckContext(exe_ctx, target_sp, process_sp, frame_sp);
373}
374
375// This is a really nasty hack, meant to fix Objective-C expressions of the form
376// (int)[myArray count].  Right now, because the type information for count is
377// not available, [myArray count] returns id, which can't be directly cast to
378// int without causing a clang error.
379static void
380ApplyObjcCastHack(std::string &expr)
381{
382#define OBJC_CAST_HACK_FROM "(int)["
383#define OBJC_CAST_HACK_TO   "(int)(long long)["
384
385    size_t from_offset;
386
387    while ((from_offset = expr.find(OBJC_CAST_HACK_FROM)) != expr.npos)
388        expr.replace(from_offset, sizeof(OBJC_CAST_HACK_FROM) - 1, OBJC_CAST_HACK_TO);
389
390#undef OBJC_CAST_HACK_TO
391#undef OBJC_CAST_HACK_FROM
392}
393
394// Another hack, meant to allow use of unichar despite it not being available in
395// the type information.  Although we could special-case it in type lookup,
396// hopefully we'll figure out a way to #include the same environment as is
397// present in the original source file rather than try to hack specific type
398// definitions in as needed.
399static void
400ApplyUnicharHack(std::string &expr)
401{
402#define UNICHAR_HACK_FROM "unichar"
403#define UNICHAR_HACK_TO   "unsigned short"
404
405    size_t from_offset;
406
407    while ((from_offset = expr.find(UNICHAR_HACK_FROM)) != expr.npos)
408        expr.replace(from_offset, sizeof(UNICHAR_HACK_FROM) - 1, UNICHAR_HACK_TO);
409
410#undef UNICHAR_HACK_TO
411#undef UNICHAR_HACK_FROM
412}
413
414bool
415ClangUserExpression::Parse (Stream &error_stream,
416                            ExecutionContext &exe_ctx,
417                            lldb_private::ExecutionPolicy execution_policy,
418                            bool keep_result_in_memory)
419{
420    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
421
422    Error err;
423
424    InstallContext(exe_ctx);
425
426    ScanContext(exe_ctx, err);
427
428    if (!err.Success())
429    {
430        error_stream.Printf("warning: %s\n", err.AsCString());
431    }
432
433    StreamString m_transformed_stream;
434
435    ////////////////////////////////////
436    // Generate the expression
437    //
438
439    ApplyObjcCastHack(m_expr_text);
440    //ApplyUnicharHack(m_expr_text);
441
442    std::unique_ptr<ExpressionSourceCode> source_code (ExpressionSourceCode::CreateWrapped(m_expr_prefix.c_str(), m_expr_text.c_str()));
443
444    lldb::LanguageType lang_type;
445
446    if (m_cplusplus)
447        lang_type = lldb::eLanguageTypeC_plus_plus;
448    else if(m_objectivec)
449        lang_type = lldb::eLanguageTypeObjC;
450    else
451        lang_type = lldb::eLanguageTypeC;
452
453    if (!source_code->GetText(m_transformed_text, lang_type, m_const_object, m_static_method))
454    {
455        error_stream.PutCString ("error: couldn't construct expression body");
456        return false;
457    }
458
459    if (log)
460        log->Printf("Parsing the following code:\n%s", m_transformed_text.c_str());
461
462    ////////////////////////////////////
463    // Set up the target and compiler
464    //
465
466    Target *target = exe_ctx.GetTargetPtr();
467
468    if (!target)
469    {
470        error_stream.PutCString ("error: invalid target\n");
471        return false;
472    }
473
474    //////////////////////////
475    // Parse the expression
476    //
477
478    m_materializer_ap.reset(new Materializer());
479
480    m_expr_decl_map.reset(new ClangExpressionDeclMap(keep_result_in_memory, exe_ctx));
481
482    class OnExit
483    {
484    public:
485        typedef std::function <void (void)> Callback;
486
487        OnExit (Callback const &callback) :
488            m_callback(callback)
489        {
490        }
491
492        ~OnExit ()
493        {
494            m_callback();
495        }
496    private:
497        Callback m_callback;
498    };
499
500    OnExit on_exit([this]() { m_expr_decl_map.reset(); });
501
502    if (!m_expr_decl_map->WillParse(exe_ctx, m_materializer_ap.get()))
503    {
504        error_stream.PutCString ("error: current process state is unsuitable for expression parsing\n");
505
506        m_expr_decl_map.reset(); // We are being careful here in the case of breakpoint conditions.
507
508        return false;
509    }
510
511    Process *process = exe_ctx.GetProcessPtr();
512    ExecutionContextScope *exe_scope = process;
513
514    if (!exe_scope)
515        exe_scope = exe_ctx.GetTargetPtr();
516
517    ClangExpressionParser parser(exe_scope, *this);
518
519    unsigned num_errors = parser.Parse (error_stream);
520
521    if (num_errors)
522    {
523        error_stream.Printf ("error: %d errors parsing expression\n", num_errors);
524
525        m_expr_decl_map.reset(); // We are being careful here in the case of breakpoint conditions.
526
527        return false;
528    }
529
530    //////////////////////////////////////////////////////////////////////////////////////////
531    // Prepare the output of the parser for execution, evaluating it statically if possible
532    //
533
534    Error jit_error = parser.PrepareForExecution (m_jit_start_addr,
535                                                  m_jit_end_addr,
536                                                  m_execution_unit_ap,
537                                                  exe_ctx,
538                                                  m_can_interpret,
539                                                  execution_policy);
540
541    m_expr_decl_map.reset(); // Make this go away since we don't need any of its state after parsing.  This also gets rid of any ClangASTImporter::Minions.
542
543    if (jit_error.Success())
544    {
545        if (process && m_jit_start_addr != LLDB_INVALID_ADDRESS)
546            m_jit_process_wp = lldb::ProcessWP(process->shared_from_this());
547        return true;
548    }
549    else
550    {
551        const char *error_cstr = jit_error.AsCString();
552        if (error_cstr && error_cstr[0])
553            error_stream.Printf ("error: %s\n", error_cstr);
554        else
555            error_stream.Printf ("error: expression can't be interpreted or run\n");
556        return false;
557    }
558}
559
560static lldb::addr_t
561GetObjectPointer (lldb::StackFrameSP frame_sp,
562                  ConstString &object_name,
563                  Error &err)
564{
565    err.Clear();
566
567    if (!frame_sp)
568    {
569        err.SetErrorStringWithFormat("Couldn't load '%s' because the context is incomplete", object_name.AsCString());
570        return LLDB_INVALID_ADDRESS;
571    }
572
573    lldb::VariableSP var_sp;
574    lldb::ValueObjectSP valobj_sp;
575
576    valobj_sp = frame_sp->GetValueForVariableExpressionPath(object_name.AsCString(),
577                                                            lldb::eNoDynamicValues,
578                                                            StackFrame::eExpressionPathOptionCheckPtrVsMember ||
579                                                            StackFrame::eExpressionPathOptionsAllowDirectIVarAccess ||
580                                                            StackFrame::eExpressionPathOptionsNoFragileObjcIvar ||
581                                                            StackFrame::eExpressionPathOptionsNoSyntheticChildren ||
582                                                            StackFrame::eExpressionPathOptionsNoSyntheticArrayRange,
583                                                            var_sp,
584                                                            err);
585
586    if (!err.Success())
587        return LLDB_INVALID_ADDRESS;
588
589    lldb::addr_t ret = valobj_sp->GetValueAsUnsigned(LLDB_INVALID_ADDRESS);
590
591    if (ret == LLDB_INVALID_ADDRESS)
592    {
593        err.SetErrorStringWithFormat("Couldn't load '%s' because its value couldn't be evaluated", object_name.AsCString());
594        return LLDB_INVALID_ADDRESS;
595    }
596
597    return ret;
598}
599
600bool
601ClangUserExpression::PrepareToExecuteJITExpression (Stream &error_stream,
602                                                    ExecutionContext &exe_ctx,
603                                                    lldb::addr_t &struct_address,
604                                                    lldb::addr_t &object_ptr,
605                                                    lldb::addr_t &cmd_ptr)
606{
607    lldb::TargetSP target;
608    lldb::ProcessSP process;
609    lldb::StackFrameSP frame;
610
611    if (!LockAndCheckContext(exe_ctx,
612                             target,
613                             process,
614                             frame))
615    {
616        error_stream.Printf("The context has changed before we could JIT the expression!\n");
617        return false;
618    }
619
620    if (m_jit_start_addr != LLDB_INVALID_ADDRESS || m_can_interpret)
621    {
622        if (m_needs_object_ptr)
623        {
624            ConstString object_name;
625
626            if (m_cplusplus)
627            {
628                object_name.SetCString("this");
629            }
630            else if (m_objectivec)
631            {
632                object_name.SetCString("self");
633            }
634            else
635            {
636                error_stream.Printf("Need object pointer but don't know the language\n");
637                return false;
638            }
639
640            Error object_ptr_error;
641
642            object_ptr = GetObjectPointer(frame, object_name, object_ptr_error);
643
644            if (!object_ptr_error.Success())
645            {
646                error_stream.Printf("warning: couldn't get required object pointer (substituting NULL): %s\n", object_ptr_error.AsCString());
647                object_ptr = 0;
648            }
649
650            if (m_objectivec)
651            {
652                ConstString cmd_name("_cmd");
653
654                cmd_ptr = GetObjectPointer(frame, cmd_name, object_ptr_error);
655
656                if (!object_ptr_error.Success())
657                {
658                    error_stream.Printf("warning: couldn't get cmd pointer (substituting NULL): %s\n", object_ptr_error.AsCString());
659                    cmd_ptr = 0;
660                }
661            }
662        }
663
664        if (m_materialized_address == LLDB_INVALID_ADDRESS)
665        {
666            Error alloc_error;
667
668            IRMemoryMap::AllocationPolicy policy = m_can_interpret ? IRMemoryMap::eAllocationPolicyHostOnly : IRMemoryMap::eAllocationPolicyMirror;
669
670            m_materialized_address = m_execution_unit_ap->Malloc(m_materializer_ap->GetStructByteSize(),
671                                                                 m_materializer_ap->GetStructAlignment(),
672                                                                 lldb::ePermissionsReadable | lldb::ePermissionsWritable,
673                                                                 policy,
674                                                                 alloc_error);
675
676            if (!alloc_error.Success())
677            {
678                error_stream.Printf("Couldn't allocate space for materialized struct: %s\n", alloc_error.AsCString());
679                return false;
680            }
681        }
682
683        struct_address = m_materialized_address;
684
685        if (m_can_interpret && m_stack_frame_bottom == LLDB_INVALID_ADDRESS)
686        {
687            Error alloc_error;
688
689            const size_t stack_frame_size = 512 * 1024;
690
691            m_stack_frame_bottom = m_execution_unit_ap->Malloc(stack_frame_size,
692                                                               8,
693                                                               lldb::ePermissionsReadable | lldb::ePermissionsWritable,
694                                                               IRMemoryMap::eAllocationPolicyHostOnly,
695                                                               alloc_error);
696
697            m_stack_frame_top = m_stack_frame_bottom + stack_frame_size;
698
699            if (!alloc_error.Success())
700            {
701                error_stream.Printf("Couldn't allocate space for the stack frame: %s\n", alloc_error.AsCString());
702                return false;
703            }
704        }
705
706        Error materialize_error;
707
708        m_dematerializer_sp = m_materializer_ap->Materialize(frame, *m_execution_unit_ap, struct_address, materialize_error);
709
710        if (!materialize_error.Success())
711        {
712            error_stream.Printf("Couldn't materialize struct: %s\n", materialize_error.AsCString());
713            return false;
714        }
715    }
716    return true;
717}
718
719bool
720ClangUserExpression::FinalizeJITExecution (Stream &error_stream,
721                                           ExecutionContext &exe_ctx,
722                                           lldb::ClangExpressionVariableSP &result,
723                                           lldb::addr_t function_stack_bottom,
724                                           lldb::addr_t function_stack_top)
725{
726    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
727
728    if (log)
729        log->Printf("-- [ClangUserExpression::FinalizeJITExecution] Dematerializing after execution --");
730
731    if (!m_dematerializer_sp)
732    {
733        error_stream.Printf ("Couldn't apply expression side effects : no dematerializer is present");
734        return false;
735    }
736
737    Error dematerialize_error;
738
739    m_dematerializer_sp->Dematerialize(dematerialize_error, result, function_stack_bottom, function_stack_top);
740
741    if (!dematerialize_error.Success())
742    {
743        error_stream.Printf ("Couldn't apply expression side effects : %s\n", dematerialize_error.AsCString("unknown error"));
744        return false;
745    }
746
747    if (result)
748        result->TransferAddress();
749
750    m_dematerializer_sp.reset();
751
752    return true;
753}
754
755ExecutionResults
756ClangUserExpression::Execute (Stream &error_stream,
757                              ExecutionContext &exe_ctx,
758                              const EvaluateExpressionOptions& options,
759                              ClangUserExpression::ClangUserExpressionSP &shared_ptr_to_me,
760                              lldb::ClangExpressionVariableSP &result)
761{
762    // The expression log is quite verbose, and if you're just tracking the execution of the
763    // expression, it's quite convenient to have these logs come out with the STEP log as well.
764    Log *log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_EXPRESSIONS | LIBLLDB_LOG_STEP));
765
766    if (m_jit_start_addr != LLDB_INVALID_ADDRESS || m_can_interpret)
767    {
768        lldb::addr_t struct_address = LLDB_INVALID_ADDRESS;
769
770        lldb::addr_t object_ptr = 0;
771        lldb::addr_t cmd_ptr = 0;
772
773        if (!PrepareToExecuteJITExpression (error_stream, exe_ctx, struct_address, object_ptr, cmd_ptr))
774        {
775            error_stream.Printf("Errored out in %s, couldn't PrepareToExecuteJITExpression", __FUNCTION__);
776            return eExecutionSetupError;
777        }
778
779        lldb::addr_t function_stack_bottom = LLDB_INVALID_ADDRESS;
780        lldb::addr_t function_stack_top = LLDB_INVALID_ADDRESS;
781
782        if (m_can_interpret)
783        {
784            llvm::Module *module = m_execution_unit_ap->GetModule();
785            llvm::Function *function = m_execution_unit_ap->GetFunction();
786
787            if (!module || !function)
788            {
789                error_stream.Printf("Supposed to interpret, but nothing is there");
790                return eExecutionSetupError;
791            }
792
793            Error interpreter_error;
794
795            llvm::SmallVector <lldb::addr_t, 3> args;
796
797            if (m_needs_object_ptr)
798            {
799                args.push_back(object_ptr);
800
801                if (m_objectivec)
802                    args.push_back(cmd_ptr);
803            }
804
805            args.push_back(struct_address);
806
807            function_stack_bottom = m_stack_frame_bottom;
808            function_stack_top = m_stack_frame_top;
809
810            IRInterpreter::Interpret (*module,
811                                      *function,
812                                      args,
813                                      *m_execution_unit_ap.get(),
814                                      interpreter_error,
815                                      function_stack_bottom,
816                                      function_stack_top);
817
818            if (!interpreter_error.Success())
819            {
820                error_stream.Printf("Supposed to interpret, but failed: %s", interpreter_error.AsCString());
821                return eExecutionDiscarded;
822            }
823        }
824        else
825        {
826            Address wrapper_address (m_jit_start_addr);
827
828            llvm::SmallVector <lldb::addr_t, 3> args;
829
830            if (m_needs_object_ptr) {
831                args.push_back(object_ptr);
832                if (m_objectivec)
833                    args.push_back(cmd_ptr);
834            }
835
836            args.push_back(struct_address);
837
838            lldb::ThreadPlanSP call_plan_sp(new ThreadPlanCallUserExpression (exe_ctx.GetThreadRef(),
839                                                                              wrapper_address,
840                                                                              args,
841                                                                              options,
842                                                                              shared_ptr_to_me));
843
844            if (!call_plan_sp || !call_plan_sp->ValidatePlan (&error_stream))
845                return eExecutionSetupError;
846
847            lldb::addr_t function_stack_pointer = static_cast<ThreadPlanCallFunction *>(call_plan_sp.get())->GetFunctionStackPointer();
848
849            function_stack_bottom = function_stack_pointer - Host::GetPageSize();
850            function_stack_top = function_stack_pointer;
851
852            if (log)
853                log->Printf("-- [ClangUserExpression::Execute] Execution of expression begins --");
854
855            if (exe_ctx.GetProcessPtr())
856                exe_ctx.GetProcessPtr()->SetRunningUserExpression(true);
857
858            ExecutionResults execution_result = exe_ctx.GetProcessRef().RunThreadPlan (exe_ctx,
859                                                                                       call_plan_sp,
860                                                                                       options,
861                                                                                       error_stream);
862
863            if (exe_ctx.GetProcessPtr())
864                exe_ctx.GetProcessPtr()->SetRunningUserExpression(false);
865
866            if (log)
867                log->Printf("-- [ClangUserExpression::Execute] Execution of expression completed --");
868
869            if (execution_result == eExecutionInterrupted || execution_result == eExecutionHitBreakpoint)
870            {
871                const char *error_desc = NULL;
872
873                if (call_plan_sp)
874                {
875                    lldb::StopInfoSP real_stop_info_sp = call_plan_sp->GetRealStopInfo();
876                    if (real_stop_info_sp)
877                        error_desc = real_stop_info_sp->GetDescription();
878                }
879                if (error_desc)
880                    error_stream.Printf ("Execution was interrupted, reason: %s.", error_desc);
881                else
882                    error_stream.PutCString ("Execution was interrupted.");
883
884                if ((execution_result == eExecutionInterrupted && options.DoesUnwindOnError())
885                    || (execution_result == eExecutionHitBreakpoint && options.DoesIgnoreBreakpoints()))
886                    error_stream.PutCString ("\nThe process has been returned to the state before expression evaluation.");
887                else
888                    error_stream.PutCString ("\nThe process has been left at the point where it was interrupted, use \"thread return -x\" to return to the state before expression evaluation.");
889
890                return execution_result;
891            }
892            else if (execution_result == eExecutionStoppedForDebug)
893            {
894                    error_stream.PutCString ("Execution was halted at the first instruction of the expression function because \"debug\" was requested.\n"
895                                             "Use \"thread return -x\" to return to the state before expression evaluation.");
896                    return execution_result;
897            }
898            else if (execution_result != eExecutionCompleted)
899            {
900                error_stream.Printf ("Couldn't execute function; result was %s\n", Process::ExecutionResultAsCString (execution_result));
901                return execution_result;
902            }
903        }
904
905        if  (FinalizeJITExecution (error_stream, exe_ctx, result, function_stack_bottom, function_stack_top))
906        {
907            return eExecutionCompleted;
908        }
909        else
910        {
911            return eExecutionSetupError;
912        }
913    }
914    else
915    {
916        error_stream.Printf("Expression can't be run, because there is no JIT compiled function");
917        return eExecutionSetupError;
918    }
919}
920
921ExecutionResults
922ClangUserExpression::Evaluate (ExecutionContext &exe_ctx,
923                               const EvaluateExpressionOptions& options,
924                               const char *expr_cstr,
925                               const char *expr_prefix,
926                               lldb::ValueObjectSP &result_valobj_sp,
927                               Error &error)
928{
929    Log *log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_EXPRESSIONS | LIBLLDB_LOG_STEP));
930
931    lldb_private::ExecutionPolicy execution_policy = options.GetExecutionPolicy();
932    const lldb::LanguageType language = options.GetLanguage();
933    const ResultType desired_type = options.DoesCoerceToId() ? ClangUserExpression::eResultTypeId : ClangUserExpression::eResultTypeAny;
934    ExecutionResults execution_results = eExecutionSetupError;
935
936    Process *process = exe_ctx.GetProcessPtr();
937
938    if (process == NULL || process->GetState() != lldb::eStateStopped)
939    {
940        if (execution_policy == eExecutionPolicyAlways)
941        {
942            if (log)
943                log->Printf("== [ClangUserExpression::Evaluate] Expression may not run, but is not constant ==");
944
945            error.SetErrorString ("expression needed to run but couldn't");
946
947            return execution_results;
948        }
949    }
950
951    if (process == NULL || !process->CanJIT())
952        execution_policy = eExecutionPolicyNever;
953
954    ClangUserExpressionSP user_expression_sp (new ClangUserExpression (expr_cstr, expr_prefix, language, desired_type));
955
956    StreamString error_stream;
957
958    if (log)
959        log->Printf("== [ClangUserExpression::Evaluate] Parsing expression %s ==", expr_cstr);
960
961    const bool keep_expression_in_memory = true;
962
963    if (!user_expression_sp->Parse (error_stream, exe_ctx, execution_policy, keep_expression_in_memory))
964    {
965        if (error_stream.GetString().empty())
966            error.SetErrorString ("expression failed to parse, unknown error");
967        else
968            error.SetErrorString (error_stream.GetString().c_str());
969    }
970    else
971    {
972        lldb::ClangExpressionVariableSP expr_result;
973
974        if (execution_policy == eExecutionPolicyNever &&
975            !user_expression_sp->CanInterpret())
976        {
977            if (log)
978                log->Printf("== [ClangUserExpression::Evaluate] Expression may not run, but is not constant ==");
979
980            if (error_stream.GetString().empty())
981                error.SetErrorString ("expression needed to run but couldn't");
982        }
983        else
984        {
985            error_stream.GetString().clear();
986
987            if (log)
988                log->Printf("== [ClangUserExpression::Evaluate] Executing expression ==");
989
990            execution_results = user_expression_sp->Execute (error_stream,
991                                                             exe_ctx,
992                                                             options,
993                                                             user_expression_sp,
994                                                             expr_result);
995
996            if (execution_results != eExecutionCompleted)
997            {
998                if (log)
999                    log->Printf("== [ClangUserExpression::Evaluate] Execution completed abnormally ==");
1000
1001                if (error_stream.GetString().empty())
1002                    error.SetErrorString ("expression failed to execute, unknown error");
1003                else
1004                    error.SetErrorString (error_stream.GetString().c_str());
1005            }
1006            else
1007            {
1008                if (expr_result)
1009                {
1010                    result_valobj_sp = expr_result->GetValueObject();
1011
1012                    if (log)
1013                        log->Printf("== [ClangUserExpression::Evaluate] Execution completed normally with result %s ==", result_valobj_sp->GetValueAsCString());
1014                }
1015                else
1016                {
1017                    if (log)
1018                        log->Printf("== [ClangUserExpression::Evaluate] Execution completed normally with no result ==");
1019
1020                    error.SetError(ClangUserExpression::kNoResult, lldb::eErrorTypeGeneric);
1021                }
1022            }
1023        }
1024    }
1025
1026    if (result_valobj_sp.get() == NULL)
1027    {
1028        result_valobj_sp = ValueObjectConstResult::Create (exe_ctx.GetBestExecutionContextScope(), error);
1029    }
1030
1031    return execution_results;
1032}
1033