<rdar://problem/13159777>
lldb was mmap'ing archive files once per .o file it loads, now it correctly shares the archive between modules.
LLDB was also always mapping entire contents of universal mach-o files, now it maps just the slice that is required.
Added a new logging channel for "lldb" called "mmap" to help track future regressions.
Modified the ObjectFile and ObjectContainer plugin interfaces to take a data offset along with the file offset and size so we can implement the correct caching and efficient reading of parts of files without mmap'ing the entire file like we used to.
The current implementation still keeps entire .a files mmaped (once) and entire slices from universal files mmaped to ensure that if a client builds their binaries during a debug session we don't lose our data and get corrupt object file info and debug info.
llvm-svn: 174524
diff --git a/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp b/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
index a430c26..6d6d1ec 100644
--- a/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
+++ b/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
@@ -173,19 +173,30 @@
ObjectFile *
ObjectFileELF::CreateInstance (const lldb::ModuleSP &module_sp,
DataBufferSP &data_sp,
- const FileSpec *file,
- addr_t offset,
- addr_t length)
+ lldb::offset_t data_offset,
+ const lldb_private::FileSpec* file,
+ lldb::offset_t file_offset,
+ lldb::offset_t length)
{
- if (data_sp && data_sp->GetByteSize() > (llvm::ELF::EI_NIDENT + offset))
+ if (!data_sp)
{
- const uint8_t *magic = data_sp->GetBytes() + offset;
+ data_sp = file->MemoryMapFileContents(file_offset, length);
+ data_offset = 0;
+ }
+
+ if (data_sp && data_sp->GetByteSize() > (llvm::ELF::EI_NIDENT + data_offset))
+ {
+ const uint8_t *magic = data_sp->GetBytes() + data_offset;
if (ELFHeader::MagicBytesMatch(magic))
{
+ // Update the data to contain the entire file
+ // Update the data to contain the entire file if it doesn't already
+ if (data_sp->GetByteSize() < length)
+ data_sp = file->MemoryMapFileContents(file_offset, length);
unsigned address_size = ELFHeader::AddressSizeInBytes(magic);
if (address_size == 4 || address_size == 8)
{
- std::auto_ptr<ObjectFileELF> objfile_ap(new ObjectFileELF(module_sp, data_sp, file, offset, length));
+ std::auto_ptr<ObjectFileELF> objfile_ap(new ObjectFileELF(module_sp, data_sp, data_offset, file, file_offset, length));
ArchSpec spec;
if (objfile_ap->GetArchitecture(spec) &&
objfile_ap->SetModulesArchitecture(spec))
@@ -232,11 +243,12 @@
//------------------------------------------------------------------
ObjectFileELF::ObjectFileELF (const lldb::ModuleSP &module_sp,
- DataBufferSP& dataSP,
+ DataBufferSP& data_sp,
+ lldb::offset_t data_offset,
const FileSpec* file,
- addr_t offset,
- addr_t length) :
- ObjectFile(module_sp, file, offset, length, dataSP),
+ lldb::offset_t file_offset,
+ lldb::offset_t length) :
+ ObjectFile(module_sp, file, file_offset, length, data_sp, data_offset),
m_header(),
m_program_headers(),
m_section_headers(),
@@ -291,7 +303,7 @@
bool
ObjectFileELF::ParseHeader()
{
- lldb::offset_t offset = GetOffset();
+ lldb::offset_t offset = GetFileOffset();
return m_header.Parse(m_data, &offset);
}