Files
clang-p2996/lldb/source/Plugins/Language/CPlusPlus/LibCxxInitializerList.cpp
Adrian Prantl 0e4c482124 Pass ConstString by value (NFC)
My apologies for the large patch. With the exception of ConstString.h
itself it was entirely produced by sed.

ConstString has exactly one const char * data member, so passing a
ConstString by reference is not any more efficient than copying it by
value. In both cases a single pointer is passed. But passing it by
value makes it harder to accidentally return the address of a local
object.

(This fixes rdar://problem/48640859 for the Apple folks)

Differential Revision: https://reviews.llvm.org/D59030

llvm-svn: 355553
2019-03-06 21:22:25 +00:00

123 lines
3.8 KiB
C++

//===-- LibCxxInitializerList.cpp -------------------------------*- C++ -*-===//
//
// 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 "LibCxx.h"
#include "lldb/Core/ValueObject.h"
#include "lldb/DataFormatters/FormattersHelpers.h"
#include "lldb/Utility/ConstString.h"
using namespace lldb;
using namespace lldb_private;
using namespace lldb_private::formatters;
namespace lldb_private {
namespace formatters {
class LibcxxInitializerListSyntheticFrontEnd
: public SyntheticChildrenFrontEnd {
public:
LibcxxInitializerListSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
~LibcxxInitializerListSyntheticFrontEnd() override;
size_t CalculateNumChildren() override;
lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
bool Update() override;
bool MightHaveChildren() override;
size_t GetIndexOfChildWithName(ConstString name) override;
private:
ValueObject *m_start;
CompilerType m_element_type;
uint32_t m_element_size;
size_t m_num_elements;
};
} // namespace formatters
} // namespace lldb_private
lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::
LibcxxInitializerListSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
: SyntheticChildrenFrontEnd(*valobj_sp), m_start(nullptr), m_element_type(),
m_element_size(0), m_num_elements(0) {
if (valobj_sp)
Update();
}
lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::
~LibcxxInitializerListSyntheticFrontEnd() {
// this needs to stay around because it's a child object who will follow its
// parent's life cycle
// delete m_start;
}
size_t lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::
CalculateNumChildren() {
static ConstString g___size_("__size_");
m_num_elements = 0;
ValueObjectSP size_sp(m_backend.GetChildMemberWithName(g___size_, true));
if (size_sp)
m_num_elements = size_sp->GetValueAsUnsigned(0);
return m_num_elements;
}
lldb::ValueObjectSP lldb_private::formatters::
LibcxxInitializerListSyntheticFrontEnd::GetChildAtIndex(size_t idx) {
if (!m_start)
return lldb::ValueObjectSP();
uint64_t offset = idx * m_element_size;
offset = offset + m_start->GetValueAsUnsigned(0);
StreamString name;
name.Printf("[%" PRIu64 "]", (uint64_t)idx);
return CreateValueObjectFromAddress(name.GetString(), offset,
m_backend.GetExecutionContextRef(),
m_element_type);
}
bool lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::
Update() {
static ConstString g___begin_("__begin_");
m_start = nullptr;
m_num_elements = 0;
m_element_type = m_backend.GetCompilerType().GetTypeTemplateArgument(0);
if (!m_element_type.IsValid())
return false;
if (llvm::Optional<uint64_t> size = m_element_type.GetByteSize(nullptr)) {
m_element_size = *size;
// Store raw pointers or end up with a circular dependency.
m_start = m_backend.GetChildMemberWithName(g___begin_, true).get();
}
return false;
}
bool lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::
MightHaveChildren() {
return true;
}
size_t lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::
GetIndexOfChildWithName(ConstString name) {
if (!m_start)
return UINT32_MAX;
return ExtractIndexFromString(name.GetCString());
}
lldb_private::SyntheticChildrenFrontEnd *
lldb_private::formatters::LibcxxInitializerListSyntheticFrontEndCreator(
CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
return (valobj_sp ? new LibcxxInitializerListSyntheticFrontEnd(valobj_sp)
: nullptr);
}