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Track transition from launch dyld to shared-cache dyld #4826

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Merged
merged 1 commit into from
Jun 14, 2022
Merged

Track transition from launch dyld to shared-cache dyld #4826

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2 changes: 2 additions & 0 deletions lldb/source/Plugins/DynamicLoader/MacOSX-DYLD/DynamicLoaderDarwin.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -611,6 +611,8 @@ ModuleSP DynamicLoaderDarwin::GetDYLDModule() {
return dyld_sp;
}

void DynamicLoaderDarwin::ClearDYLDModule() { m_dyld_module_wp.reset(); }

bool DynamicLoaderDarwin::AddModulesUsingImageInfos(
ImageInfo::collection &image_infos) {
std::lock_guard<std::recursive_mutex> guard(m_mutex);
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2 changes: 2 additions & 0 deletions lldb/source/Plugins/DynamicLoader/MacOSX-DYLD/DynamicLoaderDarwin.h
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Expand Up @@ -71,6 +71,8 @@ class DynamicLoaderDarwin : public lldb_private::DynamicLoader {

lldb::ModuleSP GetDYLDModule();

void ClearDYLDModule();

class Segment {
public:
Segment() : name() {}
Expand Down
68 changes: 66 additions & 2 deletions lldb/source/Plugins/DynamicLoader/MacOSX-DYLD/DynamicLoaderMacOS.cpp
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Expand Up @@ -14,6 +14,7 @@
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Symbol/SymbolVendor.h"
#include "lldb/Target/ABI.h"
#include "lldb/Target/SectionLoadList.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/Thread.h"
Expand Down Expand Up @@ -76,13 +77,16 @@ DynamicLoader *DynamicLoaderMacOS::CreateInstance(Process *process,
// Constructor
DynamicLoaderMacOS::DynamicLoaderMacOS(Process *process)
: DynamicLoaderDarwin(process), m_image_infos_stop_id(UINT32_MAX),
m_break_id(LLDB_INVALID_BREAK_ID), m_mutex(),
m_break_id(LLDB_INVALID_BREAK_ID),
m_dyld_handover_break_id(LLDB_INVALID_BREAK_ID), m_mutex(),
m_maybe_image_infos_address(LLDB_INVALID_ADDRESS) {}

// Destructor
DynamicLoaderMacOS::~DynamicLoaderMacOS() {
if (LLDB_BREAK_ID_IS_VALID(m_break_id))
m_process->GetTarget().RemoveBreakpointByID(m_break_id);
if (LLDB_BREAK_ID_IS_VALID(m_dyld_handover_break_id))
m_process->GetTarget().RemoveBreakpointByID(m_dyld_handover_break_id);
}

bool DynamicLoaderMacOS::ProcessDidExec() {
Expand Down Expand Up @@ -135,8 +139,11 @@ void DynamicLoaderMacOS::DoClear() {

if (LLDB_BREAK_ID_IS_VALID(m_break_id))
m_process->GetTarget().RemoveBreakpointByID(m_break_id);
if (LLDB_BREAK_ID_IS_VALID(m_dyld_handover_break_id))
m_process->GetTarget().RemoveBreakpointByID(m_dyld_handover_break_id);

m_break_id = LLDB_INVALID_BREAK_ID;
m_dyld_handover_break_id = LLDB_INVALID_BREAK_ID;
}

// Check if we have found DYLD yet
Expand Down Expand Up @@ -286,13 +293,50 @@ bool DynamicLoaderMacOS::NotifyBreakpointHit(void *baton,
}
if (dyld_mode == 0) {
// dyld_notify_adding
dyld_instance->AddBinaries(image_load_addresses);
if (process->GetTarget().GetImages().GetSize() == 0) {
// When all images have been removed, we're doing the
// dyld handover from a launch-dyld to a shared-cache-dyld,
// and we've just hit our one-shot address breakpoint in
// the sc-dyld. Note that the image addresses passed to
// this function are inferior sizeof(void*) not uint64_t's
// like our normal notification, so don't even look at
// image_load_addresses.

dyld_instance->ClearDYLDHandoverBreakpoint();

dyld_instance->DoInitialImageFetch();
dyld_instance->SetNotificationBreakpoint();
} else {
dyld_instance->AddBinaries(image_load_addresses);
}
} else if (dyld_mode == 1) {
// dyld_notify_removing
dyld_instance->UnloadImages(image_load_addresses);
} else if (dyld_mode == 2) {
// dyld_notify_remove_all
dyld_instance->UnloadAllImages();
} else if (dyld_mode == 3 && image_infos_count == 1) {
// dyld_image_dyld_moved

dyld_instance->ClearNotificationBreakpoint();
dyld_instance->UnloadAllImages();
dyld_instance->ClearDYLDModule();
process->GetTarget().GetImages().Clear();
process->GetTarget().GetSectionLoadList().Clear();

addr_t all_image_infos = process->GetImageInfoAddress();
int addr_size =
process->GetTarget().GetArchitecture().GetAddressByteSize();
addr_t notification_location = all_image_infos + 4 + // version
4 + // infoArrayCount
addr_size; // infoArray
Status error;
addr_t notification_addr =
process->ReadPointerFromMemory(notification_location, error);
if (ABISP abi_sp = process->GetABI())
notification_addr = abi_sp->FixCodeAddress(notification_addr);

dyld_instance->SetDYLDHandoverBreakpoint(notification_addr);
}
}
}
Expand Down Expand Up @@ -371,6 +415,26 @@ bool DynamicLoaderMacOS::SetNotificationBreakpoint() {
return m_break_id != LLDB_INVALID_BREAK_ID;
}

bool DynamicLoaderMacOS::SetDYLDHandoverBreakpoint(
addr_t notification_address) {
if (m_dyld_handover_break_id == LLDB_INVALID_BREAK_ID) {
BreakpointSP dyld_handover_bp = m_process->GetTarget().CreateBreakpoint(
notification_address, true, false);
dyld_handover_bp->SetCallback(DynamicLoaderMacOS::NotifyBreakpointHit, this,
true);
dyld_handover_bp->SetOneShot(true);
m_dyld_handover_break_id = dyld_handover_bp->GetID();
return true;
}
return false;
}

void DynamicLoaderMacOS::ClearDYLDHandoverBreakpoint() {
if (LLDB_BREAK_ID_IS_VALID(m_dyld_handover_break_id))
m_process->GetTarget().RemoveBreakpointByID(m_dyld_handover_break_id);
m_dyld_handover_break_id = LLDB_INVALID_BREAK_ID;
}

addr_t
DynamicLoaderMacOS::GetDyldLockVariableAddressFromModule(Module *module) {
SymbolContext sc;
Expand Down
5 changes: 5 additions & 0 deletions lldb/source/Plugins/DynamicLoader/MacOSX-DYLD/DynamicLoaderMacOS.h
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Original file line number Diff line number Diff line change
Expand Up @@ -71,6 +71,10 @@ class DynamicLoaderMacOS : public lldb_private::DynamicLoaderDarwin {

bool DidSetNotificationBreakpoint() override;

bool SetDYLDHandoverBreakpoint(lldb::addr_t notification_address);

void ClearDYLDHandoverBreakpoint();

void AddBinaries(const std::vector<lldb::addr_t> &load_addresses);

void DoClear() override;
Expand All @@ -94,6 +98,7 @@ class DynamicLoaderMacOS : public lldb_private::DynamicLoaderDarwin {
uint32_t m_image_infos_stop_id; // The Stop ID the last time we
// loaded/unloaded images
lldb::user_id_t m_break_id;
lldb::user_id_t m_dyld_handover_break_id;
mutable std::recursive_mutex m_mutex;
lldb::addr_t m_maybe_image_infos_address; // If dyld is still maintaining the
// all_image_infos address, store it
Expand Down