1//===-- LanguageRuntime.h ---------------------------------------------------*-
2// C++ -*-===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef LLDB_TARGET_LANGUAGERUNTIME_H
11#define LLDB_TARGET_LANGUAGERUNTIME_H
12
13#include "lldb/Breakpoint/BreakpointResolver.h"
14#include "lldb/Breakpoint/BreakpointResolverName.h"
15#include "lldb/Core/PluginInterface.h"
16#include "lldb/Core/Value.h"
17#include "lldb/Core/ValueObject.h"
18#include "lldb/Expression/LLVMUserExpression.h"
19#include "lldb/Symbol/DeclVendor.h"
20#include "lldb/Target/ExecutionContextScope.h"
21#include "lldb/Target/Runtime.h"
22#include "lldb/lldb-private.h"
23#include "lldb/lldb-public.h"
24#include <optional>
25
26namespace lldb_private {
27
28class ExceptionSearchFilter : public SearchFilter {
29public:
30 ExceptionSearchFilter(const lldb::TargetSP &target_sp,
31 lldb::LanguageType language,
32 bool update_module_list = true);
33
34 ~ExceptionSearchFilter() override = default;
35
36 bool ModulePasses(const lldb::ModuleSP &module_sp) override;
37
38 bool ModulePasses(const FileSpec &spec) override;
39
40 void Search(Searcher &searcher) override;
41
42 void GetDescription(Stream *s) override;
43
44 static SearchFilter *
45 CreateFromStructuredData(Target &target,
46 const StructuredData::Dictionary &data_dict,
47 Status &error);
48
49 StructuredData::ObjectSP SerializeToStructuredData() override;
50
51protected:
52 lldb::LanguageType m_language;
53 LanguageRuntime *m_language_runtime;
54 lldb::SearchFilterSP m_filter_sp;
55
56 lldb::SearchFilterSP DoCreateCopy() override;
57
58 void UpdateModuleListIfNeeded();
59};
60
61class LanguageRuntime : public Runtime, public PluginInterface {
62public:
63 static LanguageRuntime *FindPlugin(Process *process,
64 lldb::LanguageType language);
65
66 static void InitializeCommands(CommandObject *parent);
67
68 virtual lldb::LanguageType GetLanguageType() const = 0;
69
70 /// Return the preferred language runtime instance, which in most cases will
71 /// be the current instance.
72 virtual LanguageRuntime *GetPreferredLanguageRuntime(ValueObject &in_value) {
73 return nullptr;
74 }
75
76 virtual bool GetObjectDescription(Stream &str, ValueObject &object) = 0;
77
78 virtual bool GetObjectDescription(Stream &str, Value &value,
79 ExecutionContextScope *exe_scope) = 0;
80
81
82 struct VTableInfo {
83 Address addr; /// Address of the vtable's virtual function table
84 Symbol *symbol; /// The vtable symbol from the symbol table
85 };
86 /// Get the vtable information for a given value.
87 ///
88 /// \param[in] in_value
89 /// The value object to try and extract the VTableInfo from.
90 ///
91 /// \param[in] check_type
92 /// If true, the compiler type of \a in_value will be checked to see if
93 /// it is an instance to, or pointer or reference to a class or struct
94 /// that has a vtable. If the type doesn't meet the requirements, an
95 /// error will be returned explaining why the type isn't suitable.
96 ///
97 /// \return
98 /// An error if anything goes wrong while trying to extract the vtable
99 /// or if \a check_type is true and the type doesn't have a vtable.
100 virtual llvm::Expected<VTableInfo> GetVTableInfo(ValueObject &in_value,
101 bool check_type) {
102 return llvm::createStringError(
103 EC: std::errc::invalid_argument,
104 Fmt: "language doesn't support getting vtable information");
105 }
106
107 // this call should return true if it could set the name and/or the type
108 virtual bool GetDynamicTypeAndAddress(ValueObject &in_value,
109 lldb::DynamicValueType use_dynamic,
110 TypeAndOrName &class_type_or_name,
111 Address &address,
112 Value::ValueType &value_type) = 0;
113
114 // This call should return a CompilerType given a generic type name and an
115 // ExecutionContextScope in which one can actually fetch any specialization
116 // information required.
117 virtual CompilerType GetConcreteType(ExecutionContextScope *exe_scope,
118 ConstString abstract_type_name) {
119 return CompilerType();
120 }
121
122 // This should be a fast test to determine whether it is likely that this
123 // value would have a dynamic type.
124 virtual bool CouldHaveDynamicValue(ValueObject &in_value) = 0;
125
126 // The contract for GetDynamicTypeAndAddress() is to return a "bare-bones"
127 // dynamic type For instance, given a Base* pointer,
128 // GetDynamicTypeAndAddress() will return the type of Derived, not Derived*.
129 // The job of this API is to correct this misalignment between the static
130 // type and the discovered dynamic type
131 virtual TypeAndOrName FixUpDynamicType(const TypeAndOrName &type_and_or_name,
132 ValueObject &static_value) = 0;
133
134 virtual void SetExceptionBreakpoints() {}
135
136 virtual void ClearExceptionBreakpoints() {}
137
138 virtual bool ExceptionBreakpointsAreSet() { return false; }
139
140 virtual bool ExceptionBreakpointsExplainStop(lldb::StopInfoSP stop_reason) {
141 return false;
142 }
143
144 static lldb::BreakpointSP
145 CreateExceptionBreakpoint(Target &target, lldb::LanguageType language,
146 bool catch_bp, bool throw_bp,
147 bool is_internal = false);
148
149 static lldb::BreakpointPreconditionSP
150 GetExceptionPrecondition(lldb::LanguageType language, bool throw_bp);
151
152 virtual lldb::ValueObjectSP GetExceptionObjectForThread(
153 lldb::ThreadSP thread_sp) {
154 return lldb::ValueObjectSP();
155 }
156
157 virtual lldb::ThreadSP GetBacktraceThreadFromException(
158 lldb::ValueObjectSP thread_sp) {
159 return lldb::ThreadSP();
160 }
161
162 virtual DeclVendor *GetDeclVendor() { return nullptr; }
163
164 virtual lldb::BreakpointResolverSP
165 CreateExceptionResolver(const lldb::BreakpointSP &bkpt,
166 bool catch_bp, bool throw_bp) = 0;
167
168 virtual lldb::SearchFilterSP CreateExceptionSearchFilter() {
169 return m_process->GetTarget().GetSearchFilterForModule(containingModule: nullptr);
170 }
171
172 virtual bool GetTypeBitSize(const CompilerType &compiler_type,
173 uint64_t &size) {
174 return false;
175 }
176
177 virtual void SymbolsDidLoad(const ModuleList &module_list) {}
178
179 virtual lldb::ThreadPlanSP GetStepThroughTrampolinePlan(Thread &thread,
180 bool stop_others) = 0;
181
182 /// Identify whether a name is a runtime value that should not be hidden by
183 /// from the user interface.
184 virtual bool IsAllowedRuntimeValue(ConstString name) { return false; }
185
186 virtual std::optional<CompilerType> GetRuntimeType(CompilerType base_type) {
187 return std::nullopt;
188 }
189
190 void ModulesDidLoad(const ModuleList &module_list) override {}
191
192 // Called by ClangExpressionParser::PrepareForExecution to query for any
193 // custom LLVM IR passes that need to be run before an expression is
194 // assembled and run.
195 virtual bool GetIRPasses(LLVMUserExpression::IRPasses &custom_passes) {
196 return false;
197 }
198
199 // Given the name of a runtime symbol (e.g. in Objective-C, an ivar offset
200 // symbol), try to determine from the runtime what the value of that symbol
201 // would be. Useful when the underlying binary is stripped.
202 virtual lldb::addr_t LookupRuntimeSymbol(ConstString name) {
203 return LLDB_INVALID_ADDRESS;
204 }
205
206 virtual bool isA(const void *ClassID) const { return ClassID == &ID; }
207 static char ID;
208
209 /// A language runtime may be able to provide a special UnwindPlan for
210 /// the frame represented by the register contents \a regctx when that
211 /// frame is not following the normal ABI conventions.
212 /// Instead of using the normal UnwindPlan for the function, we will use
213 /// this special UnwindPlan for this one backtrace.
214 /// One example of this would be a language that has asynchronous functions,
215 /// functions that may not be currently-executing, while waiting on other
216 /// asynchronous calls they made, but are part of a logical backtrace that
217 /// we want to show the developer because that's how they think of the
218 /// program flow.
219 ///
220 /// \param[in] thread
221 /// The thread that the unwind is happening on.
222 ///
223 /// \param[in] regctx
224 /// The RegisterContext for the frame we need to create an UnwindPlan.
225 /// We don't yet have a StackFrame when we're selecting the UnwindPlan.
226 ///
227 /// \param[out] behaves_like_zeroth_frame
228 /// With normal ABI calls, all stack frames except the zeroth frame need
229 /// to have the return-pc value backed up by 1 for symbolication purposes.
230 /// For these LanguageRuntime unwind plans, they may not follow normal ABI
231 /// calling conventions and the return pc may need to be symbolicated
232 /// as-is.
233 ///
234 /// \return
235 /// Returns an UnwindPlan to find the caller frame if it should be used,
236 /// instead of the UnwindPlan that would normally be used for this
237 /// function.
238 static lldb::UnwindPlanSP
239 GetRuntimeUnwindPlan(lldb_private::Thread &thread,
240 lldb_private::RegisterContext *regctx,
241 bool &behaves_like_zeroth_frame);
242
243protected:
244 // The static GetRuntimeUnwindPlan method above is only implemented in the
245 // base class; subclasses may override this protected member if they can
246 // provide one of these UnwindPlans.
247 virtual lldb::UnwindPlanSP
248 GetRuntimeUnwindPlan(lldb::ProcessSP process_sp,
249 lldb_private::RegisterContext *regctx,
250 bool &behaves_like_zeroth_frame) {
251 return lldb::UnwindPlanSP();
252 }
253
254 LanguageRuntime(Process *process);
255};
256
257} // namespace lldb_private
258
259#endif // LLDB_TARGET_LANGUAGERUNTIME_H
260

source code of lldb/include/lldb/Target/LanguageRuntime.h