Ilia Kuklin fe51d8ae57
[LLDB] Add array subscription and integer parsing to DIL (#141102)
Reapply #138551 with an xfailed test on Windows
2025-05-25 21:09:33 +05:00

434 lines
16 KiB
C++

//===-- DILEval.cpp -------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "lldb/ValueObject/DILEval.h"
#include "lldb/Symbol/VariableList.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/ValueObject/DILAST.h"
#include "lldb/ValueObject/ValueObject.h"
#include "lldb/ValueObject/ValueObjectRegister.h"
#include "lldb/ValueObject/ValueObjectVariable.h"
#include "llvm/Support/FormatAdapters.h"
#include <memory>
namespace lldb_private::dil {
static lldb::ValueObjectSP LookupStaticIdentifier(
VariableList &variable_list, std::shared_ptr<StackFrame> exe_scope,
llvm::StringRef name_ref, llvm::StringRef unqualified_name) {
// First look for an exact match to the (possibly) qualified name.
for (const lldb::VariableSP &var_sp : variable_list) {
lldb::ValueObjectSP valobj_sp(
ValueObjectVariable::Create(exe_scope.get(), var_sp));
if (valobj_sp && valobj_sp->GetVariable() &&
(valobj_sp->GetVariable()->NameMatches(ConstString(name_ref))))
return valobj_sp;
}
// If the qualified name is the same as the unqualfied name, there's nothing
// more to be done.
if (name_ref == unqualified_name)
return nullptr;
// We didn't match the qualified name; try to match the unqualified name.
for (const lldb::VariableSP &var_sp : variable_list) {
lldb::ValueObjectSP valobj_sp(
ValueObjectVariable::Create(exe_scope.get(), var_sp));
if (valobj_sp && valobj_sp->GetVariable() &&
(valobj_sp->GetVariable()->NameMatches(ConstString(unqualified_name))))
return valobj_sp;
}
return nullptr;
}
static lldb::VariableSP DILFindVariable(ConstString name,
lldb::VariableListSP variable_list) {
lldb::VariableSP exact_match;
std::vector<lldb::VariableSP> possible_matches;
for (lldb::VariableSP var_sp : *variable_list) {
llvm::StringRef str_ref_name = var_sp->GetName().GetStringRef();
// Check for global vars, which might start with '::'.
str_ref_name.consume_front("::");
if (str_ref_name == name.GetStringRef())
possible_matches.push_back(var_sp);
else if (var_sp->NameMatches(name))
possible_matches.push_back(var_sp);
}
// Look for exact matches (favors local vars over global vars)
auto exact_match_it =
llvm::find_if(possible_matches, [&](lldb::VariableSP var_sp) {
return var_sp->GetName() == name;
});
if (exact_match_it != possible_matches.end())
return *exact_match_it;
// Look for a global var exact match.
for (auto var_sp : possible_matches) {
llvm::StringRef str_ref_name = var_sp->GetName().GetStringRef();
str_ref_name.consume_front("::");
if (str_ref_name == name.GetStringRef())
return var_sp;
}
// If there's a single non-exact match, take it.
if (possible_matches.size() == 1)
return possible_matches[0];
return nullptr;
}
lldb::ValueObjectSP LookupGlobalIdentifier(
llvm::StringRef name_ref, std::shared_ptr<StackFrame> stack_frame,
lldb::TargetSP target_sp, lldb::DynamicValueType use_dynamic,
CompilerType *scope_ptr) {
// First look for match in "local" global variables.
lldb::VariableListSP variable_list(stack_frame->GetInScopeVariableList(true));
name_ref.consume_front("::");
lldb::ValueObjectSP value_sp;
if (variable_list) {
lldb::VariableSP var_sp =
DILFindVariable(ConstString(name_ref), variable_list);
if (var_sp)
value_sp =
stack_frame->GetValueObjectForFrameVariable(var_sp, use_dynamic);
}
if (value_sp)
return value_sp;
// Also check for static global vars.
if (variable_list) {
const char *type_name = "";
if (scope_ptr)
type_name = scope_ptr->GetCanonicalType().GetTypeName().AsCString();
std::string name_with_type_prefix =
llvm::formatv("{0}::{1}", type_name, name_ref).str();
value_sp = LookupStaticIdentifier(*variable_list, stack_frame,
name_with_type_prefix, name_ref);
if (!value_sp)
value_sp = LookupStaticIdentifier(*variable_list, stack_frame, name_ref,
name_ref);
}
if (value_sp)
return value_sp;
// Check for match in modules global variables.
VariableList modules_var_list;
target_sp->GetImages().FindGlobalVariables(
ConstString(name_ref), std::numeric_limits<uint32_t>::max(),
modules_var_list);
if (modules_var_list.Empty())
return nullptr;
for (const lldb::VariableSP &var_sp : modules_var_list) {
std::string qualified_name = llvm::formatv("::{0}", name_ref).str();
if (var_sp->NameMatches(ConstString(name_ref)) ||
var_sp->NameMatches(ConstString(qualified_name))) {
value_sp = ValueObjectVariable::Create(stack_frame.get(), var_sp);
break;
}
}
if (value_sp)
return value_sp;
return nullptr;
}
lldb::ValueObjectSP LookupIdentifier(llvm::StringRef name_ref,
std::shared_ptr<StackFrame> stack_frame,
lldb::DynamicValueType use_dynamic,
CompilerType *scope_ptr) {
// Support $rax as a special syntax for accessing registers.
// Will return an invalid value in case the requested register doesn't exist.
if (name_ref.consume_front("$")) {
lldb::RegisterContextSP reg_ctx(stack_frame->GetRegisterContext());
if (!reg_ctx)
return nullptr;
if (const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoByName(name_ref))
return ValueObjectRegister::Create(stack_frame.get(), reg_ctx, reg_info);
return nullptr;
}
lldb::VariableListSP variable_list(
stack_frame->GetInScopeVariableList(false));
if (!name_ref.contains("::")) {
if (!scope_ptr || !scope_ptr->IsValid()) {
// Lookup in the current frame.
// Try looking for a local variable in current scope.
lldb::ValueObjectSP value_sp;
if (variable_list) {
lldb::VariableSP var_sp =
DILFindVariable(ConstString(name_ref), variable_list);
if (var_sp)
value_sp =
stack_frame->GetValueObjectForFrameVariable(var_sp, use_dynamic);
}
if (!value_sp)
value_sp = stack_frame->FindVariable(ConstString(name_ref));
if (value_sp)
return value_sp;
// Try looking for an instance variable (class member).
SymbolContext sc = stack_frame->GetSymbolContext(
lldb::eSymbolContextFunction | lldb::eSymbolContextBlock);
llvm::StringRef ivar_name = sc.GetInstanceVariableName();
value_sp = stack_frame->FindVariable(ConstString(ivar_name));
if (value_sp)
value_sp = value_sp->GetChildMemberWithName(name_ref);
if (value_sp)
return value_sp;
}
}
return nullptr;
}
Interpreter::Interpreter(lldb::TargetSP target, llvm::StringRef expr,
std::shared_ptr<StackFrame> frame_sp,
lldb::DynamicValueType use_dynamic, bool use_synthetic,
bool fragile_ivar, bool check_ptr_vs_member)
: m_target(std::move(target)), m_expr(expr), m_exe_ctx_scope(frame_sp),
m_use_dynamic(use_dynamic), m_use_synthetic(use_synthetic),
m_fragile_ivar(fragile_ivar), m_check_ptr_vs_member(check_ptr_vs_member) {
}
llvm::Expected<lldb::ValueObjectSP> Interpreter::Evaluate(const ASTNode *node) {
// Evaluate an AST.
auto value_or_error = node->Accept(this);
// Return the computed value-or-error. The caller is responsible for
// checking if an error occured during the evaluation.
return value_or_error;
}
llvm::Expected<lldb::ValueObjectSP>
Interpreter::Visit(const IdentifierNode *node) {
lldb::DynamicValueType use_dynamic = m_use_dynamic;
lldb::ValueObjectSP identifier =
LookupIdentifier(node->GetName(), m_exe_ctx_scope, use_dynamic);
if (!identifier)
identifier = LookupGlobalIdentifier(node->GetName(), m_exe_ctx_scope,
m_target, use_dynamic);
if (!identifier) {
std::string errMsg =
llvm::formatv("use of undeclared identifier '{0}'", node->GetName());
return llvm::make_error<DILDiagnosticError>(
m_expr, errMsg, node->GetLocation(), node->GetName().size());
}
return identifier;
}
llvm::Expected<lldb::ValueObjectSP>
Interpreter::Visit(const UnaryOpNode *node) {
Status error;
auto rhs_or_err = Evaluate(node->GetOperand());
if (!rhs_or_err)
return rhs_or_err;
lldb::ValueObjectSP rhs = *rhs_or_err;
switch (node->GetKind()) {
case UnaryOpKind::Deref: {
lldb::ValueObjectSP dynamic_rhs = rhs->GetDynamicValue(m_use_dynamic);
if (dynamic_rhs)
rhs = dynamic_rhs;
lldb::ValueObjectSP child_sp = rhs->Dereference(error);
if (error.Fail())
return llvm::make_error<DILDiagnosticError>(m_expr, error.AsCString(),
node->GetLocation());
return child_sp;
}
case UnaryOpKind::AddrOf: {
Status error;
lldb::ValueObjectSP value = rhs->AddressOf(error);
if (error.Fail())
return llvm::make_error<DILDiagnosticError>(m_expr, error.AsCString(),
node->GetLocation());
return value;
}
}
// Unsupported/invalid operation.
return llvm::make_error<DILDiagnosticError>(
m_expr, "invalid ast: unexpected binary operator", node->GetLocation());
}
llvm::Expected<lldb::ValueObjectSP>
Interpreter::Visit(const MemberOfNode *node) {
auto base_or_err = Evaluate(node->GetBase());
if (!base_or_err)
return base_or_err;
lldb::ValueObjectSP base = *base_or_err;
// Perform some basic type & correctness checking.
if (node->GetIsArrow()) {
if (!m_fragile_ivar) {
// Make sure we aren't trying to deref an objective
// C ivar if this is not allowed
const uint32_t pointer_type_flags =
base->GetCompilerType().GetTypeInfo(nullptr);
if ((pointer_type_flags & lldb::eTypeIsObjC) &&
(pointer_type_flags & lldb::eTypeIsPointer)) {
// This was an objective C object pointer and it was requested we
// skip any fragile ivars so return nothing here
return lldb::ValueObjectSP();
}
}
// If we have a non-pointer type with a synthetic value then lets check
// if we have a synthetic dereference specified.
if (!base->IsPointerType() && base->HasSyntheticValue()) {
Status deref_error;
if (lldb::ValueObjectSP synth_deref_sp =
base->GetSyntheticValue()->Dereference(deref_error);
synth_deref_sp && deref_error.Success()) {
base = std::move(synth_deref_sp);
}
if (!base || deref_error.Fail()) {
std::string errMsg = llvm::formatv(
"Failed to dereference synthetic value: {0}", deref_error);
return llvm::make_error<DILDiagnosticError>(
m_expr, errMsg, node->GetLocation(), node->GetFieldName().size());
}
// Some synthetic plug-ins fail to set the error in Dereference
if (!base) {
std::string errMsg = "Failed to dereference synthetic value";
return llvm::make_error<DILDiagnosticError>(
m_expr, errMsg, node->GetLocation(), node->GetFieldName().size());
}
}
}
if (m_check_ptr_vs_member) {
bool expr_is_ptr = node->GetIsArrow();
bool base_is_ptr = base->IsPointerType();
if (expr_is_ptr != base_is_ptr) {
if (base_is_ptr) {
std::string errMsg =
llvm::formatv("member reference type {0} is a pointer; "
"did you mean to use '->'?",
base->GetCompilerType().TypeDescription());
return llvm::make_error<DILDiagnosticError>(
m_expr, errMsg, node->GetLocation(), node->GetFieldName().size());
} else {
std::string errMsg =
llvm::formatv("member reference type {0} is not a pointer; "
"did you mean to use '.'?",
base->GetCompilerType().TypeDescription());
return llvm::make_error<DILDiagnosticError>(
m_expr, errMsg, node->GetLocation(), node->GetFieldName().size());
}
}
}
lldb::ValueObjectSP field_obj =
base->GetChildMemberWithName(node->GetFieldName());
if (!field_obj) {
if (m_use_synthetic) {
field_obj = base->GetSyntheticValue();
if (field_obj)
field_obj = field_obj->GetChildMemberWithName(node->GetFieldName());
}
if (!m_use_synthetic || !field_obj) {
std::string errMsg = llvm::formatv(
"no member named '{0}' in {1}", node->GetFieldName(),
base->GetCompilerType().GetFullyUnqualifiedType().TypeDescription());
return llvm::make_error<DILDiagnosticError>(
m_expr, errMsg, node->GetLocation(), node->GetFieldName().size());
}
}
if (field_obj && field_obj->GetName() == node->GetFieldName()) {
if (m_use_dynamic != lldb::eNoDynamicValues) {
lldb::ValueObjectSP dynamic_val_sp =
field_obj->GetDynamicValue(m_use_dynamic);
if (dynamic_val_sp)
field_obj = dynamic_val_sp;
}
return field_obj;
}
CompilerType base_type = base->GetCompilerType();
if (node->GetIsArrow() && base->IsPointerType())
base_type = base_type.GetPointeeType();
std::string errMsg =
llvm::formatv("no member named '{0}' in {1}", node->GetFieldName(),
base_type.GetFullyUnqualifiedType().TypeDescription());
return llvm::make_error<DILDiagnosticError>(
m_expr, errMsg, node->GetLocation(), node->GetFieldName().size());
}
llvm::Expected<lldb::ValueObjectSP>
Interpreter::Visit(const ArraySubscriptNode *node) {
auto lhs_or_err = Evaluate(node->GetBase());
if (!lhs_or_err)
return lhs_or_err;
lldb::ValueObjectSP base = *lhs_or_err;
// Check to see if 'base' has a synthetic value; if so, try using that.
uint64_t child_idx = node->GetIndex();
if (lldb::ValueObjectSP synthetic = base->GetSyntheticValue()) {
llvm::Expected<uint32_t> num_children =
synthetic->GetNumChildren(child_idx + 1);
if (!num_children)
return llvm::make_error<DILDiagnosticError>(
m_expr, toString(num_children.takeError()), node->GetLocation());
if (child_idx >= *num_children) {
std::string message = llvm::formatv(
"array index {0} is not valid for \"({1}) {2}\"", child_idx,
base->GetTypeName().AsCString("<invalid type>"),
base->GetName().AsCString());
return llvm::make_error<DILDiagnosticError>(m_expr, message,
node->GetLocation());
}
if (lldb::ValueObjectSP child_valobj_sp =
synthetic->GetChildAtIndex(child_idx))
return child_valobj_sp;
}
auto base_type = base->GetCompilerType().GetNonReferenceType();
if (!base_type.IsPointerType() && !base_type.IsArrayType())
return llvm::make_error<DILDiagnosticError>(
m_expr, "subscripted value is not an array or pointer",
node->GetLocation());
if (base_type.IsPointerToVoid())
return llvm::make_error<DILDiagnosticError>(
m_expr, "subscript of pointer to incomplete type 'void'",
node->GetLocation());
if (base_type.IsArrayType()) {
if (lldb::ValueObjectSP child_valobj_sp = base->GetChildAtIndex(child_idx))
return child_valobj_sp;
}
int64_t signed_child_idx = node->GetIndex();
return base->GetSyntheticArrayMember(signed_child_idx, true);
}
} // namespace lldb_private::dil