1 //===-- ABI.cpp -------------------------------------------------*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 #include "lldb/Target/ABI.h"
10 #include "lldb/Core/PluginManager.h"
11 #include "lldb/Core/Value.h"
12 #include "lldb/Core/ValueObjectConstResult.h"
13 #include "lldb/Expression/ExpressionVariable.h"
14 #include "lldb/Symbol/CompilerType.h"
15 #include "lldb/Symbol/TypeSystem.h"
16 #include "lldb/Target/Target.h"
17 #include "lldb/Target/Thread.h"
18 #include "lldb/Utility/Log.h"
19 #include "llvm/Support/TargetRegistry.h"
22 using namespace lldb_private;
25 ABI::FindPlugin(lldb::ProcessSP process_sp, const ArchSpec &arch) {
27 ABICreateInstance create_callback;
29 for (uint32_t idx = 0;
30 (create_callback = PluginManager::GetABICreateCallbackAtIndex(idx)) !=
33 abi_sp = create_callback(process_sp, arch);
42 ABI::~ABI() = default;
44 bool ABI::GetRegisterInfoByName(ConstString name, RegisterInfo &info) {
46 const RegisterInfo *register_info_array = GetRegisterInfoArray(count);
47 if (register_info_array) {
48 const char *unique_name_cstr = name.GetCString();
50 for (i = 0; i < count; ++i) {
51 if (register_info_array[i].name == unique_name_cstr) {
52 info = register_info_array[i];
56 for (i = 0; i < count; ++i) {
57 if (register_info_array[i].alt_name == unique_name_cstr) {
58 info = register_info_array[i];
66 bool ABI::GetRegisterInfoByKind(RegisterKind reg_kind, uint32_t reg_num,
68 if (reg_kind < eRegisterKindEHFrame || reg_kind >= kNumRegisterKinds)
72 const RegisterInfo *register_info_array = GetRegisterInfoArray(count);
73 if (register_info_array) {
74 for (uint32_t i = 0; i < count; ++i) {
75 if (register_info_array[i].kinds[reg_kind] == reg_num) {
76 info = register_info_array[i];
84 ValueObjectSP ABI::GetReturnValueObject(Thread &thread, CompilerType &ast_type,
85 bool persistent) const {
86 if (!ast_type.IsValid())
87 return ValueObjectSP();
89 ValueObjectSP return_valobj_sp;
91 return_valobj_sp = GetReturnValueObjectImpl(thread, ast_type);
92 if (!return_valobj_sp)
93 return return_valobj_sp;
95 // Now turn this into a persistent variable.
96 // FIXME: This code is duplicated from Target::EvaluateExpression, and it is
97 // used in similar form in a couple
98 // of other places. Figure out the correct Create function to do all this
102 Target &target = *thread.CalculateTarget();
103 PersistentExpressionState *persistent_expression_state =
104 target.GetPersistentExpressionStateForLanguage(
105 ast_type.GetMinimumLanguage());
107 if (!persistent_expression_state)
108 return ValueObjectSP();
110 auto prefix = persistent_expression_state->GetPersistentVariablePrefix();
111 ConstString persistent_variable_name =
112 persistent_expression_state->GetNextPersistentVariableName(target,
115 lldb::ValueObjectSP const_valobj_sp;
117 // Check in case our value is already a constant value
118 if (return_valobj_sp->GetIsConstant()) {
119 const_valobj_sp = return_valobj_sp;
120 const_valobj_sp->SetName(persistent_variable_name);
123 return_valobj_sp->CreateConstantValue(persistent_variable_name);
125 lldb::ValueObjectSP live_valobj_sp = return_valobj_sp;
127 return_valobj_sp = const_valobj_sp;
129 ExpressionVariableSP expr_variable_sp(
130 persistent_expression_state->CreatePersistentVariable(
133 assert(expr_variable_sp);
135 // Set flags and live data as appropriate
137 const Value &result_value = live_valobj_sp->GetValue();
139 switch (result_value.GetValueType()) {
140 case Value::eValueTypeHostAddress:
141 case Value::eValueTypeFileAddress:
142 // we don't do anything with these for now
144 case Value::eValueTypeScalar:
145 case Value::eValueTypeVector:
146 expr_variable_sp->m_flags |=
147 ExpressionVariable::EVIsFreezeDried;
148 expr_variable_sp->m_flags |=
149 ExpressionVariable::EVIsLLDBAllocated;
150 expr_variable_sp->m_flags |=
151 ExpressionVariable::EVNeedsAllocation;
153 case Value::eValueTypeLoadAddress:
154 expr_variable_sp->m_live_sp = live_valobj_sp;
155 expr_variable_sp->m_flags |=
156 ExpressionVariable::EVIsProgramReference;
160 return_valobj_sp = expr_variable_sp->GetValueObject();
162 return return_valobj_sp;
165 ValueObjectSP ABI::GetReturnValueObject(Thread &thread, llvm::Type &ast_type,
166 bool persistent) const {
167 ValueObjectSP return_valobj_sp;
168 return_valobj_sp = GetReturnValueObjectImpl(thread, ast_type);
169 return return_valobj_sp;
172 // specialized to work with llvm IR types
174 // for now we will specify a default implementation so that we don't need to
176 lldb::ValueObjectSP ABI::GetReturnValueObjectImpl(Thread &thread,
177 llvm::Type &ir_type) const {
178 ValueObjectSP return_valobj_sp;
180 /* this is a dummy and will only be called if an ABI does not override this */
182 return return_valobj_sp;
185 bool ABI::PrepareTrivialCall(Thread &thread, lldb::addr_t sp,
186 lldb::addr_t functionAddress,
187 lldb::addr_t returnAddress, llvm::Type &returntype,
188 llvm::ArrayRef<ABI::CallArgument> args) const {
189 // dummy prepare trivial call
190 llvm_unreachable("Should never get here!");
193 bool ABI::GetFallbackRegisterLocation(
194 const RegisterInfo *reg_info,
195 UnwindPlan::Row::RegisterLocation &unwind_regloc) {
196 // Did the UnwindPlan fail to give us the caller's stack pointer? The stack
197 // pointer is defined to be the same as THIS frame's CFA, so return the CFA
198 // value as the caller's stack pointer. This is true on x86-32/x86-64 at
200 if (reg_info->kinds[eRegisterKindGeneric] == LLDB_REGNUM_GENERIC_SP) {
201 unwind_regloc.SetIsCFAPlusOffset(0);
205 // If a volatile register is being requested, we don't want to forward the
206 // next frame's register contents up the stack -- the register is not
207 // retrievable at this frame.
208 if (RegisterIsVolatile(reg_info)) {
209 unwind_regloc.SetUndefined();
216 std::unique_ptr<llvm::MCRegisterInfo> ABI::MakeMCRegisterInfo(const ArchSpec &arch) {
217 std::string triple = arch.GetTriple().getTriple();
218 std::string lookup_error;
219 const llvm::Target *target =
220 llvm::TargetRegistry::lookupTarget(triple, lookup_error);
222 LLDB_LOG(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS),
223 "Failed to create an llvm target for {0}: {1}", triple,
227 std::unique_ptr<llvm::MCRegisterInfo> info_up(
228 target->createMCRegInfo(triple));