From 156d16cb04c387e103060c863c83ba14d6458fa5 Mon Sep 17 00:00:00 2001 From: Sean Callanan Date: Tue, 9 Oct 2012 23:45:42 +0000 Subject: [PATCH] Thinned the AppleObjCRuntimeV2's class descriptors. The following are now derived lazily: - The name of the class (cached); - the instance size of the class (not cached); The following have been removed entirely: - Whether the class is realized. This is an implementation detail. - The contents of the objc_class object. That object can be read as needed. - Whether the class is valid. The fact that we vended a class to begin with means it's valid. We will only give up looking parts of it up if they are not in the format we expect. llvm-svn: 165567 --- lldb/include/lldb/Target/ObjCLanguageRuntime.h | 7 - .../ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp | 350 +++++++-------------- 2 files changed, 118 insertions(+), 239 deletions(-) diff --git a/lldb/include/lldb/Target/ObjCLanguageRuntime.h b/lldb/include/lldb/Target/ObjCLanguageRuntime.h index 034c147..97cefdc 100644 --- a/lldb/include/lldb/Target/ObjCLanguageRuntime.h +++ b/lldb/include/lldb/Target/ObjCLanguageRuntime.h @@ -98,13 +98,6 @@ public: virtual uint64_t GetInstanceSize () = 0; - virtual bool - IsRealized () - { - // anything other than some instances of v2 classes are always realized - return true; - } - // use to implement version-specific additional constraints on pointers virtual bool CheckPointer (lldb::addr_t value, diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp index 179fde2..e5ad473 100644 --- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp +++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp @@ -981,63 +981,32 @@ private: // or populates them. A ClassDescriptorV2 should only ever exist in a cache. ClassDescriptorV2 (AppleObjCRuntimeV2 &runtime, ObjCLanguageRuntime::ObjCISA isa) : m_runtime (runtime), - m_valid (false), - m_objc_class_ptr (0), - m_objc_class (), - m_name (), - m_instance_size (0), - m_realized (eLazyBoolCalculate), - m_process_wp () + m_objc_class_ptr (isa), + m_name () { - Initialize (isa, m_runtime.GetProcessSP()); } public: virtual ConstString GetClassName () { - if (m_valid && !m_name) + if (!m_name) { - const lldb::addr_t class_ro_t_ptr = get_class_ro_t_ptr (); - - ProcessSP process_sp = m_process_wp.lock(); - + lldb::ProcessSP process_sp = m_runtime.GetProcessSP(); + if (process_sp) { - const size_t ptr_size = process_sp->GetAddressByteSize(); + std::auto_ptr objc_class; + std::auto_ptr class_ro; + std::auto_ptr class_rw; - Error error; - lldb::addr_t name_ptr = process_sp->ReadPointerFromMemory (class_ro_t_ptr - + sizeof(uint32_t) // uint32_t flags - + sizeof(uint32_t) // uint32_t instanceStart - + sizeof(uint32_t) // uint32_t instanceSize - + (ptr_size == 8 ? sizeof(uint32_t) : 0) // uint32_t reserved (__LP64__ only) - + ptr_size, // const uint8_t *ivarLayout - error); + if (!Read_objc_class(process_sp, objc_class)) + return m_name; + if (!Read_class_row(process_sp, *objc_class, class_ro, class_rw)) + return m_name; - if (error.Success()) - { - char class_name_cstr[1024]; - - size_t count = process_sp->ReadCStringFromMemory(name_ptr, class_name_cstr, sizeof(class_name_cstr), error); - - if (error.Fail()) - { - m_valid = false; - } - else - { - if (count) - m_name.SetCString(class_name_cstr); - else - m_valid = false; - } - } - else - m_valid = false; + m_name = ConstString(class_ro->m_name.c_str()); } - else - m_valid = false; } return m_name; } @@ -1045,16 +1014,23 @@ public: virtual ObjCLanguageRuntime::ClassDescriptorSP GetSuperclass () { - if (!m_valid) + lldb::ProcessSP process_sp = m_runtime.GetProcessSP(); + + if (!process_sp) return ObjCLanguageRuntime::ClassDescriptorSP(); - return m_runtime.ObjCLanguageRuntime::GetClassDescriptor(m_objc_class.m_superclass); + std::auto_ptr objc_class; + + if (!Read_objc_class(process_sp, objc_class)) + return ObjCLanguageRuntime::ClassDescriptorSP(); + + return m_runtime.ObjCLanguageRuntime::GetClassDescriptor(objc_class->m_superclass); } virtual bool IsValid () { - return m_valid; + return true; // any Objective-C v2 runtime class descriptor we vend is valid } virtual bool @@ -1066,39 +1042,28 @@ public: virtual uint64_t GetInstanceSize () { - if (!m_valid) - return 0; + lldb::ProcessSP process_sp = m_runtime.GetProcessSP(); - if (m_instance_size == 0) + if (process_sp) { - const lldb::addr_t class_ro_t_ptr = get_class_ro_t_ptr (); + std::auto_ptr objc_class; + std::auto_ptr class_ro; + std::auto_ptr class_rw; - ProcessSP process_sp = m_process_wp.lock(); + if (!Read_objc_class(process_sp, objc_class)) + return 0; + if (!Read_class_row(process_sp, *objc_class, class_ro, class_rw)) + return 0; - if (process_sp) - { - Error error; - m_instance_size = process_sp->ReadUnsignedIntegerFromMemory(class_ro_t_ptr - + sizeof(uint32_t) // uint32_t flags - + sizeof(uint32_t), // uint32_t instanceStart - sizeof(uint32_t), - 0, - error); - if (error.Fail()) - m_valid = false; - } - else - m_valid = false; + return class_ro->m_instanceSize; } - return m_instance_size; + + return 0; } virtual ObjCLanguageRuntime::ObjCISA GetISA () - { - if (!m_valid) - return 0; - + { return m_objc_class_ptr; } @@ -1107,45 +1072,28 @@ public: std::function const &instance_method_func, std::function const &class_method_func) { - if (!m_valid) - return false; - - std::auto_ptr ro; - std::auto_ptr rw; - - ProcessSP process_sp = m_process_wp.lock(); - - if (!process_sp) - return false; + lldb::ProcessSP process_sp = m_runtime.GetProcessSP(); + + std::auto_ptr objc_class; + std::auto_ptr class_ro; + std::auto_ptr class_rw; - if (IsRealized()) - { - rw.reset(new class_rw_t); - if (!rw->Read(process_sp, m_objc_class.m_data_ptr)) - return false; - - ro.reset(new class_ro_t); - if (!ro->Read(process_sp, rw->m_ro_ptr)) - return false; - } - else - { - ro.reset(new class_ro_t); - if (!ro->Read(process_sp, m_objc_class.m_data_ptr)) - return false; - } + if (!Read_objc_class(process_sp, objc_class)) + return 0; + if (!Read_class_row(process_sp, *objc_class, class_ro, class_rw)) + return 0; static ConstString NSObject_name("NSObject"); if (m_name != NSObject_name && superclass_func) - superclass_func(m_objc_class.m_superclass); + superclass_func(objc_class->m_superclass); if (instance_method_func) { std::auto_ptr base_method_list; base_method_list.reset(new method_list_t); - if (!base_method_list->Read(process_sp, ro->m_baseMethods_ptr)) + if (!base_method_list->Read(process_sp, class_ro->m_baseMethods_ptr)) return false; if (base_method_list->m_entsize != method_t::GetSize(process_sp)) @@ -1164,7 +1112,7 @@ public: if (class_method_func) { - ObjCLanguageRuntime::ClassDescriptorSP metaclass = m_runtime.ObjCLanguageRuntime::GetClassDescriptor(m_objc_class.m_isa); + ObjCLanguageRuntime::ClassDescriptorSP metaclass = m_runtime.ObjCLanguageRuntime::GetClassDescriptor(objc_class->m_isa); // We don't care about the metaclass's superclass, or its class methods. Its instance methods are // our class methods. @@ -1178,133 +1126,10 @@ public: return true; } - virtual bool - IsRealized () - { - if (!m_valid) - return false; - - if (m_realized == eLazyBoolCalculate) - { - if (class_row_t_flags() & RW_REALIZED) - m_realized = eLazyBoolYes; - else - m_realized = eLazyBoolNo; - } - return m_realized == eLazyBoolYes; - } - virtual ~ClassDescriptorV2 () { } - -protected: - virtual bool - CheckPointer (lldb::addr_t value, uint32_t ptr_size) const - { - if (ptr_size != 8) - return true; - return ((value & 0xFFFF800000000000) == 0); - } - - uint32_t - class_row_t_flags () - { - if (m_valid && m_objc_class.m_data_ptr) - { - ProcessSP process_sp (m_process_wp.lock()); - if (process_sp) - { - Error error; - uint32_t class_row_t_flags = process_sp->ReadUnsignedIntegerFromMemory(m_objc_class.m_data_ptr, sizeof(uint32_t), 0, error); - if (error.Success()) - return class_row_t_flags; - else - m_valid = false; - } - } - return 0; - } - - lldb::addr_t - get_class_ro_t_ptr () - { - if (m_valid && m_objc_class.m_data_ptr) - { - if (IsRealized()) - { - ProcessSP process_sp (m_process_wp.lock()); - if (process_sp) - { - lldb::addr_t class_rw_t_ptr = m_objc_class.m_data_ptr; - - Error error; - const lldb::addr_t class_ro_t_ptr = process_sp->ReadPointerFromMemory (class_rw_t_ptr - + sizeof(uint32_t) // uint32_t flags - + sizeof(uint32_t), // uint32_t version - error); - - if (error.Success() && IsPointerValid(class_ro_t_ptr, process_sp->GetAddressByteSize())) - return class_ro_t_ptr; - else - m_valid = false; - } - else - m_valid = false; - } - else - { - return m_objc_class.m_data_ptr; - } - } - return 0; - } - - void - Initialize (ObjCLanguageRuntime::ObjCISA objc_class_ptr, lldb::ProcessSP process_sp) - { - if (!objc_class_ptr || !process_sp) - { - m_valid = false; - return; - } - m_valid = true; - - - m_objc_class_ptr = objc_class_ptr; - - size_t ptr_size = process_sp->GetAddressByteSize(); - Error error; - - const bool allow_NULLs = false; - const bool allow_tagged = false; - const bool check_version_specific = true; - - if (!IsPointerValid(m_objc_class_ptr, ptr_size, allow_NULLs, allow_tagged, check_version_specific)) - { - m_valid = false; - return; - } - - if (!m_objc_class.Read(process_sp, m_objc_class_ptr)) - { - m_valid = false; - return; - } - - // Now we just want to grab the instance size and the name. - // Since we find out whether the class is realized on the way, we'll remember that too. - - // The flags for class_r[ow]_t always are the first uint32_t. So just read that. - if (!IsPointerValid(m_objc_class.m_data_ptr, ptr_size, allow_NULLs, allow_tagged, check_version_specific)) - { - m_valid = false; - return; - } - - m_process_wp = process_sp; - } private: static const uint32_t RW_REALIZED = (1 << 31); @@ -1389,6 +1214,8 @@ private: lldb::addr_t m_weakIvarLayout_ptr; lldb::addr_t m_baseProperties_ptr; + std::string m_name; + bool Read(ProcessSP &process_sp, lldb::addr_t addr) { size_t ptr_size = process_sp->GetAddressByteSize(); @@ -1433,6 +1260,17 @@ private: m_weakIvarLayout_ptr = extractor.GetAddress_unchecked(&cursor); m_baseProperties_ptr = extractor.GetAddress_unchecked(&cursor); + DataBufferHeap name_buf(1024, '\0'); + + process_sp->ReadCStringFromMemory(m_name_ptr, (char*)name_buf.GetBytes(), name_buf.GetByteSize(), error); + + if (error.Fail()) + { + return false; + } + + m_name.assign((char*)name_buf.GetBytes()); + return true; } }; @@ -1575,17 +1413,65 @@ private: return true; } }; + + bool Read_objc_class (lldb::ProcessSP process_sp, std::auto_ptr &objc_class) + { + objc_class.reset(new objc_class_t); + + bool ret = objc_class->Read (process_sp, m_objc_class_ptr); + + if (!ret) + objc_class.reset(); + + return ret; + } + + bool Read_class_row (lldb::ProcessSP process_sp, const objc_class_t &objc_class, std::auto_ptr &class_ro, std::auto_ptr &class_rw) + { + class_ro.reset(); + class_rw.reset(); + + Error error; + uint32_t class_row_t_flags = process_sp->ReadUnsignedIntegerFromMemory(objc_class.m_data_ptr, sizeof(uint32_t), 0, error); + if (!error.Success()) + return false; - AppleObjCRuntimeV2 &m_runtime; // The runtime, so we can read our metaclass. - bool m_valid; // Gates whether we trust anything here at all. - lldb::addr_t m_objc_class_ptr; // The address of the objc_class_t. - objc_class_t m_objc_class; + if (class_row_t_flags & RW_REALIZED) + { + class_rw.reset(new class_rw_t); + + if (!class_rw->Read(process_sp, objc_class.m_data_ptr)) + { + class_rw.reset(); + return false; + } + + class_ro.reset(new class_ro_t); + + if (!class_ro->Read(process_sp, class_rw->m_ro_ptr)) + { + class_rw.reset(); + class_ro.reset(); + return false; + } + } + else + { + class_ro.reset(new class_ro_t); + + if (!class_ro->Read(process_sp, objc_class.m_data_ptr)) + { + class_ro.reset(); + return false; + } + } + + return true; + } - // cached information from the class_r[ow]_t - ConstString m_name; - uint32_t m_instance_size; - LazyBool m_realized; - lldb::ProcessWP m_process_wp; + AppleObjCRuntimeV2 &m_runtime; // The runtime, so we can read information lazily. + lldb::addr_t m_objc_class_ptr; // The address of the objc_class_t. (I.e., objects of this class type have this as their ISA) + ConstString m_name; // May be NULL }; class ClassDescriptorV2Tagged : public ObjCLanguageRuntime::ClassDescriptor -- 2.7.4