diff options
Diffstat (limited to 'lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp')
| -rw-r--r-- | lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp | 48 |
1 files changed, 42 insertions, 6 deletions
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp index f80015f977b..75a0a6a085e 100644 --- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp +++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp @@ -568,9 +568,9 @@ AppleObjCRuntimeV2::GetByteOffsetForIvar (ClangASTType &parent_ast_type, const c // tagged pointers are marked by having their least-significant bit // set. this makes them "invalid" as pointers because they violate -// the alignment requirements. this way, we can always know when -// we are dealing with a tagged pointer, and use the lookup approach -// that the runtime would +// the alignment requirements. of course, this detection algorithm +// is not accurate (it might become better by incorporating further +// knowledge about the internals of tagged pointers) bool AppleObjCRuntimeV2::IsTaggedPointer(lldb::addr_t ptr) { @@ -578,6 +578,9 @@ AppleObjCRuntimeV2::IsTaggedPointer(lldb::addr_t ptr) } +// this code relies on the assumption that an Objective-C object always starts +// with an ISA at offset 0. an ISA is effectively a pointer to an instance of +// struct class_t in the ObjCv2 runtime lldb_private::ObjCLanguageRuntime::ObjCISA AppleObjCRuntimeV2::GetISA(ValueObject& valobj) { @@ -587,8 +590,8 @@ AppleObjCRuntimeV2::GetISA(ValueObject& valobj) { // when using the expression parser, an additional layer of "frozen data" // can be created, which is basically a byte-exact copy of the data returned - // by the expression, but in host memory. because Python code might need to read - // into the object memory in non-obvious ways, we need to hand it the target version + // by the expression, but in host memory. because this code reads memory without + // taking the debug-info-provided object layout, we need to hand it the target version // of the expression output lldb::addr_t tgt_address = valobj.GetValueAsUnsigned(); ValueObjectSP target_object = ValueObjectConstResult::Create (valobj.GetExecutionContextScope(), @@ -647,9 +650,20 @@ AppleObjCRuntimeV2::GetActualTypeName(lldb_private::ObjCLanguageRuntime::ObjCISA uint8_t pointer_size = m_process->GetAddressByteSize(); Error error; + + /* + struct class_t *isa; + struct class_t *superclass; + Cache cache; + IMP *vtable; +--> uintptr_t data_NEVER_USE; + WARNING: this data_NEVER_USE pointer might one day contain flags in the least-significant bits + currently, rdar://problem/8955342 prevents the runtime from doing so + it presently is just a pointer to a class_rw_t + */ + lldb::addr_t rw_pointer = isa + (4 * pointer_size); //printf("rw_pointer: %llx\n", rw_pointer); - uint64_t data_pointer = m_process->ReadUnsignedIntegerFromMemory(rw_pointer, pointer_size, 0, @@ -657,6 +671,12 @@ AppleObjCRuntimeV2::GetActualTypeName(lldb_private::ObjCLanguageRuntime::ObjCISA if (error.Fail()) return ConstString("unknown"); + /* + uint32_t flags; + uint32_t version; + +--> const class_ro_t *ro; + */ data_pointer += 8; //printf("data_pointer: %llx\n", data_pointer); uint64_t ro_pointer = m_process->ReadUnsignedIntegerFromMemory(data_pointer, @@ -666,6 +686,18 @@ AppleObjCRuntimeV2::GetActualTypeName(lldb_private::ObjCLanguageRuntime::ObjCISA if (error.Fail()) return ConstString("unknown"); + /* + uint32_t flags; + uint32_t instanceStart; + uint32_t instanceSize; + #ifdef __LP64__ + uint32_t reserved; + #endif + + const uint8_t * ivarLayout; + +--> const char * name; + */ ro_pointer += 12; if (pointer_size == 8) ro_pointer += 4; @@ -722,6 +754,10 @@ AppleObjCRuntimeV2::GetParentClass(lldb_private::ObjCLanguageRuntime::ObjCISA is uint8_t pointer_size = m_process->GetAddressByteSize(); Error error; + /* + struct class_t *isa; +--> struct class_t *superclass; + */ lldb::addr_t parent_pointer = isa + pointer_size; //printf("rw_pointer: %llx\n", rw_pointer); |
