diff options
Diffstat (limited to 'lldb/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp')
| -rw-r--r-- | lldb/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp | 1263 |
1 files changed, 69 insertions, 1194 deletions
diff --git a/lldb/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp b/lldb/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp index 1f01cf3ace9..e298b856d39 100644 --- a/lldb/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp +++ b/lldb/source/Plugins/UnwindAssembly/x86/UnwindAssembly-x86.cpp @@ -8,6 +8,7 @@ //===----------------------------------------------------------------------===// #include "UnwindAssembly-x86.h" +#include "x86AssemblyInspectionEngine.h" #include "llvm-c/Disassembler.h" #include "llvm/ADT/STLExtras.h" @@ -30,1200 +31,39 @@ using namespace lldb; using namespace lldb_private; -enum CPU { k_i386, k_x86_64 }; - -enum i386_register_numbers { - k_machine_eax = 0, - k_machine_ecx = 1, - k_machine_edx = 2, - k_machine_ebx = 3, - k_machine_esp = 4, - k_machine_ebp = 5, - k_machine_esi = 6, - k_machine_edi = 7, - k_machine_eip = 8 -}; - -enum x86_64_register_numbers { - k_machine_rax = 0, - k_machine_rcx = 1, - k_machine_rdx = 2, - k_machine_rbx = 3, - k_machine_rsp = 4, - k_machine_rbp = 5, - k_machine_rsi = 6, - k_machine_rdi = 7, - k_machine_r8 = 8, - k_machine_r9 = 9, - k_machine_r10 = 10, - k_machine_r11 = 11, - k_machine_r12 = 12, - k_machine_r13 = 13, - k_machine_r14 = 14, - k_machine_r15 = 15, - k_machine_rip = 16 -}; - -struct regmap_ent { - const char *name; - int machine_regno; - int lldb_regno; -}; - -static struct regmap_ent i386_register_map[] = { - {"eax", k_machine_eax, -1}, {"ecx", k_machine_ecx, -1}, - {"edx", k_machine_edx, -1}, {"ebx", k_machine_ebx, -1}, - {"esp", k_machine_esp, -1}, {"ebp", k_machine_ebp, -1}, - {"esi", k_machine_esi, -1}, {"edi", k_machine_edi, -1}, - {"eip", k_machine_eip, -1}}; - -const int size_of_i386_register_map = llvm::array_lengthof(i386_register_map); - -static int i386_register_map_initialized = 0; - -static struct regmap_ent x86_64_register_map[] = { - {"rax", k_machine_rax, -1}, {"rcx", k_machine_rcx, -1}, - {"rdx", k_machine_rdx, -1}, {"rbx", k_machine_rbx, -1}, - {"rsp", k_machine_rsp, -1}, {"rbp", k_machine_rbp, -1}, - {"rsi", k_machine_rsi, -1}, {"rdi", k_machine_rdi, -1}, - {"r8", k_machine_r8, -1}, {"r9", k_machine_r9, -1}, - {"r10", k_machine_r10, -1}, {"r11", k_machine_r11, -1}, - {"r12", k_machine_r12, -1}, {"r13", k_machine_r13, -1}, - {"r14", k_machine_r14, -1}, {"r15", k_machine_r15, -1}, - {"rip", k_machine_rip, -1}}; - -const int size_of_x86_64_register_map = - llvm::array_lengthof(x86_64_register_map); - -static int x86_64_register_map_initialized = 0; - //----------------------------------------------------------------------------------------------- -// AssemblyParse_x86 local-file class definition & implementation functions +// UnwindAssemblyParser_x86 method definitions //----------------------------------------------------------------------------------------------- -class AssemblyParse_x86 { -public: - AssemblyParse_x86(const ExecutionContext &exe_ctx, int cpu, ArchSpec &arch, - AddressRange func); - - ~AssemblyParse_x86(); - - bool get_non_call_site_unwind_plan(UnwindPlan &unwind_plan); - - bool augment_unwind_plan_from_call_site(AddressRange &func, - UnwindPlan &unwind_plan); - - bool get_fast_unwind_plan(AddressRange &func, UnwindPlan &unwind_plan); - - bool find_first_non_prologue_insn(Address &address); - -private: - enum { kMaxInstructionByteSize = 32 }; - - bool nonvolatile_reg_p(int machine_regno); - bool push_rbp_pattern_p(); - bool push_0_pattern_p(); - bool mov_rsp_rbp_pattern_p(); - bool sub_rsp_pattern_p(int &amount); - bool add_rsp_pattern_p(int &amount); - bool lea_rsp_pattern_p(int &amount); - bool push_reg_p(int ®no); - bool pop_reg_p(int ®no); - bool push_imm_pattern_p(); - bool mov_reg_to_local_stack_frame_p(int ®no, int &fp_offset); - bool ret_pattern_p(); - bool pop_rbp_pattern_p(); - bool leave_pattern_p(); - bool call_next_insn_pattern_p(); - uint32_t extract_4(uint8_t *b); - bool machine_regno_to_lldb_regno(int machine_regno, uint32_t &lldb_regno); - bool instruction_length(Address addr, int &length); - - const ExecutionContext m_exe_ctx; - - AddressRange m_func_bounds; - - Address m_cur_insn; - uint8_t m_cur_insn_bytes[kMaxInstructionByteSize]; - - uint32_t m_machine_ip_regnum; - uint32_t m_machine_sp_regnum; - uint32_t m_machine_fp_regnum; - - uint32_t m_lldb_ip_regnum; - uint32_t m_lldb_sp_regnum; - uint32_t m_lldb_fp_regnum; - - int m_wordsize; - int m_cpu; - ArchSpec m_arch; - ::LLVMDisasmContextRef m_disasm_context; - - DISALLOW_COPY_AND_ASSIGN(AssemblyParse_x86); -}; - -AssemblyParse_x86::AssemblyParse_x86(const ExecutionContext &exe_ctx, int cpu, - ArchSpec &arch, AddressRange func) - : m_exe_ctx(exe_ctx), m_func_bounds(func), m_cur_insn(), - m_machine_ip_regnum(LLDB_INVALID_REGNUM), - m_machine_sp_regnum(LLDB_INVALID_REGNUM), - m_machine_fp_regnum(LLDB_INVALID_REGNUM), - m_lldb_ip_regnum(LLDB_INVALID_REGNUM), - m_lldb_sp_regnum(LLDB_INVALID_REGNUM), - m_lldb_fp_regnum(LLDB_INVALID_REGNUM), m_wordsize(-1), m_cpu(cpu), - m_arch(arch) { - int *initialized_flag = NULL; - if (cpu == k_i386) { - m_machine_ip_regnum = k_machine_eip; - m_machine_sp_regnum = k_machine_esp; - m_machine_fp_regnum = k_machine_ebp; - m_wordsize = 4; - initialized_flag = &i386_register_map_initialized; - } else { - m_machine_ip_regnum = k_machine_rip; - m_machine_sp_regnum = k_machine_rsp; - m_machine_fp_regnum = k_machine_rbp; - m_wordsize = 8; - initialized_flag = &x86_64_register_map_initialized; - } - - // we only look at prologue - it will be complete earlier than 512 bytes into - // func - if (m_func_bounds.GetByteSize() == 0) - m_func_bounds.SetByteSize(512); - - Thread *thread = m_exe_ctx.GetThreadPtr(); - if (thread && *initialized_flag == 0) { - RegisterContext *reg_ctx = thread->GetRegisterContext().get(); - if (reg_ctx) { - struct regmap_ent *ent; - int count, i; - if (cpu == k_i386) { - ent = i386_register_map; - count = size_of_i386_register_map; - } else { - ent = x86_64_register_map; - count = size_of_x86_64_register_map; - } - for (i = 0; i < count; i++, ent++) { - const RegisterInfo *ri = reg_ctx->GetRegisterInfoByName(ent->name); - if (ri) - ent->lldb_regno = ri->kinds[eRegisterKindLLDB]; - } - *initialized_flag = 1; - } - } - - // on initial construction we may not have a Thread so these have to remain - // uninitialized until we can get a RegisterContext to set up the register map - // table - if (*initialized_flag == 1) { - uint32_t lldb_regno; - if (machine_regno_to_lldb_regno(m_machine_sp_regnum, lldb_regno)) - m_lldb_sp_regnum = lldb_regno; - if (machine_regno_to_lldb_regno(m_machine_fp_regnum, lldb_regno)) - m_lldb_fp_regnum = lldb_regno; - if (machine_regno_to_lldb_regno(m_machine_ip_regnum, lldb_regno)) - m_lldb_ip_regnum = lldb_regno; - } - - m_disasm_context = - ::LLVMCreateDisasm(m_arch.GetTriple().getTriple().c_str(), (void *)this, - /*TagType=*/1, NULL, NULL); -} - -AssemblyParse_x86::~AssemblyParse_x86() { - ::LLVMDisasmDispose(m_disasm_context); -} - -// This function expects an x86 native register number (i.e. the bits stripped -// out of the -// actual instruction), not an lldb register number. - -bool AssemblyParse_x86::nonvolatile_reg_p(int machine_regno) { - if (m_cpu == k_i386) { - switch (machine_regno) { - case k_machine_ebx: - case k_machine_ebp: // not actually a nonvolatile but often treated as such - // by convention - case k_machine_esi: - case k_machine_edi: - case k_machine_esp: - return true; - default: - return false; - } - } - if (m_cpu == k_x86_64) { - switch (machine_regno) { - case k_machine_rbx: - case k_machine_rsp: - case k_machine_rbp: // not actually a nonvolatile but often treated as such - // by convention - case k_machine_r12: - case k_machine_r13: - case k_machine_r14: - case k_machine_r15: - return true; - default: - return false; - } - } - return false; -} - -// Macro to detect if this is a REX mode prefix byte. -#define REX_W_PREFIX_P(opcode) (((opcode) & (~0x5)) == 0x48) - -// The high bit which should be added to the source register number (the "R" -// bit) -#define REX_W_SRCREG(opcode) (((opcode)&0x4) >> 2) +UnwindAssembly_x86::UnwindAssembly_x86(const ArchSpec &arch) + : lldb_private::UnwindAssembly(arch), + m_assembly_inspection_engine(new x86AssemblyInspectionEngine(arch)) {} -// The high bit which should be added to the destination register number (the -// "B" bit) -#define REX_W_DSTREG(opcode) ((opcode)&0x1) - -// pushq %rbp [0x55] -bool AssemblyParse_x86::push_rbp_pattern_p() { - uint8_t *p = m_cur_insn_bytes; - if (*p == 0x55) - return true; - return false; +UnwindAssembly_x86::~UnwindAssembly_x86() { + delete m_assembly_inspection_engine; } -// pushq $0 ; the first instruction in start() [0x6a 0x00] -bool AssemblyParse_x86::push_0_pattern_p() { - uint8_t *p = m_cur_insn_bytes; - if (*p == 0x6a && *(p + 1) == 0x0) - return true; - return false; -} - -// pushq $0 -// pushl $0 -bool AssemblyParse_x86::push_imm_pattern_p() { - uint8_t *p = m_cur_insn_bytes; - if (*p == 0x68 || *p == 0x6a) - return true; - return false; -} - -// movq %rsp, %rbp [0x48 0x8b 0xec] or [0x48 0x89 0xe5] -// movl %esp, %ebp [0x8b 0xec] or [0x89 0xe5] -bool AssemblyParse_x86::mov_rsp_rbp_pattern_p() { - uint8_t *p = m_cur_insn_bytes; - if (m_wordsize == 8 && *p == 0x48) - p++; - if (*(p) == 0x8b && *(p + 1) == 0xec) - return true; - if (*(p) == 0x89 && *(p + 1) == 0xe5) - return true; - return false; -} - -// subq $0x20, %rsp -bool AssemblyParse_x86::sub_rsp_pattern_p(int &amount) { - uint8_t *p = m_cur_insn_bytes; - if (m_wordsize == 8 && *p == 0x48) - p++; - // 8-bit immediate operand - if (*p == 0x83 && *(p + 1) == 0xec) { - amount = (int8_t) * (p + 2); - return true; - } - // 32-bit immediate operand - if (*p == 0x81 && *(p + 1) == 0xec) { - amount = (int32_t)extract_4(p + 2); - return true; - } - return false; -} - -// addq $0x20, %rsp -bool AssemblyParse_x86::add_rsp_pattern_p(int &amount) { - uint8_t *p = m_cur_insn_bytes; - if (m_wordsize == 8 && *p == 0x48) - p++; - // 8-bit immediate operand - if (*p == 0x83 && *(p + 1) == 0xc4) { - amount = (int8_t) * (p + 2); - return true; - } - // 32-bit immediate operand - if (*p == 0x81 && *(p + 1) == 0xc4) { - amount = (int32_t)extract_4(p + 2); - return true; - } - return false; -} - -// lea esp, [esp - 0x28] -// lea esp, [esp + 0x28] -bool AssemblyParse_x86::lea_rsp_pattern_p(int &amount) { - uint8_t *p = m_cur_insn_bytes; - if (m_wordsize == 8 && *p == 0x48) - p++; - - // Check opcode - if (*p != 0x8d) - return false; - - // 8 bit displacement - if (*(p + 1) == 0x64 && (*(p + 2) & 0x3f) == 0x24) { - amount = (int8_t) * (p + 3); - return true; - } - - // 32 bit displacement - if (*(p + 1) == 0xa4 && (*(p + 2) & 0x3f) == 0x24) { - amount = (int32_t)extract_4(p + 3); - return true; - } - - return false; -} - -// pushq %rbx -// pushl %ebx -bool AssemblyParse_x86::push_reg_p(int ®no) { - uint8_t *p = m_cur_insn_bytes; - int regno_prefix_bit = 0; - // If we have a rex prefix byte, check to see if a B bit is set - if (m_wordsize == 8 && *p == 0x41) { - regno_prefix_bit = 1 << 3; - p++; - } - if (*p >= 0x50 && *p <= 0x57) { - regno = (*p - 0x50) | regno_prefix_bit; - return true; - } - return false; -} - -// popq %rbx -// popl %ebx -bool AssemblyParse_x86::pop_reg_p(int ®no) { - uint8_t *p = m_cur_insn_bytes; - int regno_prefix_bit = 0; - // If we have a rex prefix byte, check to see if a B bit is set - if (m_wordsize == 8 && *p == 0x41) { - regno_prefix_bit = 1 << 3; - p++; - } - if (*p >= 0x58 && *p <= 0x5f) { - regno = (*p - 0x58) | regno_prefix_bit; - return true; - } - return false; -} - -// popq %rbp [0x5d] -// popl %ebp [0x5d] -bool AssemblyParse_x86::pop_rbp_pattern_p() { - uint8_t *p = m_cur_insn_bytes; - return (*p == 0x5d); -} - -// leave [0xc9] -bool AssemblyParse_x86::leave_pattern_p() { - uint8_t *p = m_cur_insn_bytes; - return (*p == 0xc9); -} - -// call $0 [0xe8 0x0 0x0 0x0 0x0] -bool AssemblyParse_x86::call_next_insn_pattern_p() { - uint8_t *p = m_cur_insn_bytes; - return (*p == 0xe8) && (*(p + 1) == 0x0) && (*(p + 2) == 0x0) && - (*(p + 3) == 0x0) && (*(p + 4) == 0x0); -} - -// Look for an instruction sequence storing a nonvolatile register -// on to the stack frame. - -// movq %rax, -0x10(%rbp) [0x48 0x89 0x45 0xf0] -// movl %eax, -0xc(%ebp) [0x89 0x45 0xf4] - -// The offset value returned in rbp_offset will be positive -- -// but it must be subtraced from the frame base register to get -// the actual location. The positive value returned for the offset -// is a convention used elsewhere for CFA offsets et al. - -bool AssemblyParse_x86::mov_reg_to_local_stack_frame_p(int ®no, - int &rbp_offset) { - uint8_t *p = m_cur_insn_bytes; - int src_reg_prefix_bit = 0; - int target_reg_prefix_bit = 0; - - if (m_wordsize == 8 && REX_W_PREFIX_P(*p)) { - src_reg_prefix_bit = REX_W_SRCREG(*p) << 3; - target_reg_prefix_bit = REX_W_DSTREG(*p) << 3; - if (target_reg_prefix_bit == 1) { - // rbp/ebp don't need a prefix bit - we know this isn't the - // reg we care about. - return false; - } - p++; - } - - if (*p == 0x89) { - /* Mask off the 3-5 bits which indicate the destination register - if this is a ModR/M byte. */ - int opcode_destreg_masked_out = *(p + 1) & (~0x38); - - /* Is this a ModR/M byte with Mod bits 01 and R/M bits 101 - and three bits between them, e.g. 01nnn101 - We're looking for a destination of ebp-disp8 or ebp-disp32. */ - int immsize; - if (opcode_destreg_masked_out == 0x45) - immsize = 2; - else if (opcode_destreg_masked_out == 0x85) - immsize = 4; - else - return false; - - int offset = 0; - if (immsize == 2) - offset = (int8_t) * (p + 2); - if (immsize == 4) - offset = (uint32_t)extract_4(p + 2); - if (offset > 0) - return false; - - regno = ((*(p + 1) >> 3) & 0x7) | src_reg_prefix_bit; - rbp_offset = offset > 0 ? offset : -offset; - return true; - } - return false; -} - -// ret [0xc9] or [0xc2 imm8] or [0xca imm8] -bool AssemblyParse_x86::ret_pattern_p() { - uint8_t *p = m_cur_insn_bytes; - if (*p == 0xc9 || *p == 0xc2 || *p == 0xca || *p == 0xc3) - return true; - return false; -} - -uint32_t AssemblyParse_x86::extract_4(uint8_t *b) { - uint32_t v = 0; - for (int i = 3; i >= 0; i--) - v = (v << 8) | b[i]; - return v; -} - -bool AssemblyParse_x86::machine_regno_to_lldb_regno(int machine_regno, - uint32_t &lldb_regno) { - struct regmap_ent *ent; - int count, i; - if (m_cpu == k_i386) { - ent = i386_register_map; - count = size_of_i386_register_map; - } else { - ent = x86_64_register_map; - count = size_of_x86_64_register_map; - } - for (i = 0; i < count; i++, ent++) { - if (ent->machine_regno == machine_regno) - if (ent->lldb_regno != -1) { - lldb_regno = ent->lldb_regno; - return true; - } - } - return false; -} - -bool AssemblyParse_x86::instruction_length(Address addr, int &length) { - const uint32_t max_op_byte_size = m_arch.GetMaximumOpcodeByteSize(); - llvm::SmallVector<uint8_t, 32> opcode_data; - opcode_data.resize(max_op_byte_size); - - if (!addr.IsValid()) +bool UnwindAssembly_x86::GetNonCallSiteUnwindPlanFromAssembly( + AddressRange &func, Thread &thread, UnwindPlan &unwind_plan) { + if (!func.GetBaseAddress().IsValid() || func.GetByteSize() == 0) return false; - - const bool prefer_file_cache = true; - Error error; - Target *target = m_exe_ctx.GetTargetPtr(); - if (target->ReadMemory(addr, prefer_file_cache, opcode_data.data(), - max_op_byte_size, error) == static_cast<size_t>(-1)) { + if (m_assembly_inspection_engine == nullptr) return false; - } - - char out_string[512]; - const addr_t pc = addr.GetFileAddress(); - const size_t inst_size = ::LLVMDisasmInstruction( - m_disasm_context, opcode_data.data(), max_op_byte_size, - pc, // PC value - out_string, sizeof(out_string)); - - length = inst_size; - return true; -} - -bool AssemblyParse_x86::get_non_call_site_unwind_plan(UnwindPlan &unwind_plan) { - UnwindPlan::RowSP row(new UnwindPlan::Row); - m_cur_insn = m_func_bounds.GetBaseAddress(); - addr_t current_func_text_offset = 0; - int current_sp_bytes_offset_from_cfa = 0; - UnwindPlan::Row::RegisterLocation initial_regloc; - Error error; - - if (!m_cur_insn.IsValid()) { + ProcessSP process_sp(thread.GetProcess()); + if (process_sp.get() == nullptr) return false; - } - - unwind_plan.SetPlanValidAddressRange(m_func_bounds); - unwind_plan.SetRegisterKind(eRegisterKindLLDB); - - // At the start of the function, find the CFA by adding wordsize to the SP - // register - row->SetOffset(current_func_text_offset); - row->GetCFAValue().SetIsRegisterPlusOffset(m_lldb_sp_regnum, m_wordsize); - - // caller's stack pointer value before the call insn is the CFA address - initial_regloc.SetIsCFAPlusOffset(0); - row->SetRegisterInfo(m_lldb_sp_regnum, initial_regloc); - - // saved instruction pointer can be found at CFA - wordsize. - current_sp_bytes_offset_from_cfa = m_wordsize; - initial_regloc.SetAtCFAPlusOffset(-current_sp_bytes_offset_from_cfa); - row->SetRegisterInfo(m_lldb_ip_regnum, initial_regloc); - - unwind_plan.AppendRow(row); - - // Allocate a new Row, populate it with the existing Row contents. - UnwindPlan::Row *newrow = new UnwindPlan::Row; - *newrow = *row.get(); - row.reset(newrow); - - // Track which registers have been saved so far in the prologue. - // If we see another push of that register, it's not part of the prologue. - // The register numbers used here are the machine register #'s - // (i386_register_numbers, x86_64_register_numbers). - std::vector<bool> saved_registers(32, false); - const bool prefer_file_cache = true; - - // Once the prologue has completed we'll save a copy of the unwind - // instructions - // If there is an epilogue in the middle of the function, after that epilogue - // we'll reinstate - // the unwind setup -- we assume that some code path jumps over the - // mid-function epilogue - - UnwindPlan::RowSP prologue_completed_row; // copy of prologue row of CFI - int prologue_completed_sp_bytes_offset_from_cfa; // The sp value before the - // epilogue started executed - std::vector<bool> prologue_completed_saved_registers; - - Target *target = m_exe_ctx.GetTargetPtr(); - while (m_func_bounds.ContainsFileAddress(m_cur_insn)) { - int stack_offset, insn_len; - int machine_regno; // register numbers masked directly out of instructions - uint32_t lldb_regno; // register numbers in lldb's eRegisterKindLLDB - // numbering scheme - - bool in_epilogue = false; // we're in the middle of an epilogue sequence - bool row_updated = false; // The UnwindPlan::Row 'row' has been updated - - if (!instruction_length(m_cur_insn, insn_len) || insn_len == 0 || - insn_len > kMaxInstructionByteSize) { - // An unrecognized/junk instruction - break; - } - - if (target->ReadMemory(m_cur_insn, prefer_file_cache, m_cur_insn_bytes, - insn_len, error) == static_cast<size_t>(-1)) { - // Error reading the instruction out of the file, stop scanning - break; - } - - if (push_rbp_pattern_p()) { - current_sp_bytes_offset_from_cfa += m_wordsize; - row->GetCFAValue().SetOffset(current_sp_bytes_offset_from_cfa); - UnwindPlan::Row::RegisterLocation regloc; - regloc.SetAtCFAPlusOffset(-row->GetCFAValue().GetOffset()); - row->SetRegisterInfo(m_lldb_fp_regnum, regloc); - saved_registers[m_machine_fp_regnum] = true; - row_updated = true; - } - - else if (mov_rsp_rbp_pattern_p()) { - row->GetCFAValue().SetIsRegisterPlusOffset( - m_lldb_fp_regnum, row->GetCFAValue().GetOffset()); - row_updated = true; - } - - // This is the start() function (or a pthread equivalent), it starts with a - // pushl $0x0 which puts the - // saved pc value of 0 on the stack. In this case we want to pretend we - // didn't see a stack movement at all -- - // normally the saved pc value is already on the stack by the time the - // function starts executing. - else if (push_0_pattern_p()) { - } - - else if (push_reg_p(machine_regno)) { - current_sp_bytes_offset_from_cfa += m_wordsize; - // the PUSH instruction has moved the stack pointer - if the CFA is set in - // terms of the stack pointer, - // we need to add a new row of instructions. - if (row->GetCFAValue().GetRegisterNumber() == m_lldb_sp_regnum) { - row->GetCFAValue().SetOffset(current_sp_bytes_offset_from_cfa); - row_updated = true; - } - // record where non-volatile (callee-saved, spilled) registers are saved - // on the stack - if (nonvolatile_reg_p(machine_regno) && - machine_regno_to_lldb_regno(machine_regno, lldb_regno) && - saved_registers[machine_regno] == false) { - UnwindPlan::Row::RegisterLocation regloc; - regloc.SetAtCFAPlusOffset(-current_sp_bytes_offset_from_cfa); - row->SetRegisterInfo(lldb_regno, regloc); - saved_registers[machine_regno] = true; - row_updated = true; - } - } - - else if (pop_reg_p(machine_regno)) { - current_sp_bytes_offset_from_cfa -= m_wordsize; - - if (nonvolatile_reg_p(machine_regno) && - machine_regno_to_lldb_regno(machine_regno, lldb_regno) && - saved_registers[machine_regno] == true) { - saved_registers[machine_regno] = false; - row->RemoveRegisterInfo(lldb_regno); - - if (machine_regno == (int)m_machine_fp_regnum) { - row->GetCFAValue().SetIsRegisterPlusOffset( - m_lldb_sp_regnum, row->GetCFAValue().GetOffset()); - } - - in_epilogue = true; - row_updated = true; - } - - // the POP instruction has moved the stack pointer - if the CFA is set in - // terms of the stack pointer, - // we need to add a new row of instructions. - if (row->GetCFAValue().GetRegisterNumber() == m_lldb_sp_regnum) { - row->GetCFAValue().SetIsRegisterPlusOffset( - m_lldb_sp_regnum, current_sp_bytes_offset_from_cfa); - row_updated = true; - } - } - - // The LEAVE instruction moves the value from rbp into rsp and pops - // a value off the stack into rbp (restoring the caller's rbp value). - // It is the opposite of ENTER, or 'push rbp, mov rsp rbp'. - else if (leave_pattern_p()) { - // We're going to copy the value in rbp into rsp, so re-set the sp offset - // based on the CFAValue. Also, adjust it to recognize that we're popping - // the saved rbp value off the stack. - current_sp_bytes_offset_from_cfa = row->GetCFAValue().GetOffset(); - current_sp_bytes_offset_from_cfa -= m_wordsize; - row->GetCFAValue().SetOffset(current_sp_bytes_offset_from_cfa); - - // rbp is restored to the caller's value - saved_registers[m_machine_fp_regnum] = false; - row->RemoveRegisterInfo(m_lldb_fp_regnum); - - // cfa is now in terms of rsp again. - row->GetCFAValue().SetIsRegisterPlusOffset( - m_lldb_sp_regnum, row->GetCFAValue().GetOffset()); - row->GetCFAValue().SetOffset(current_sp_bytes_offset_from_cfa); - - in_epilogue = true; - row_updated = true; - } - - else if (mov_reg_to_local_stack_frame_p(machine_regno, stack_offset) && - nonvolatile_reg_p(machine_regno) && - machine_regno_to_lldb_regno(machine_regno, lldb_regno) && - saved_registers[machine_regno] == false) { - saved_registers[machine_regno] = true; - - UnwindPlan::Row::RegisterLocation regloc; - - // stack_offset for 'movq %r15, -80(%rbp)' will be 80. - // In the Row, we want to express this as the offset from the CFA. If the - // frame base - // is rbp (like the above instruction), the CFA offset for rbp is probably - // 16. So we - // want to say that the value is stored at the CFA address - 96. - regloc.SetAtCFAPlusOffset( - -(stack_offset + row->GetCFAValue().GetOffset())); - - row->SetRegisterInfo(lldb_regno, regloc); - - row_updated = true; - } - - else if (sub_rsp_pattern_p(stack_offset)) { - current_sp_bytes_offset_from_cfa += stack_offset; - if (row->GetCFAValue().GetRegisterNumber() == m_lldb_sp_regnum) { - row->GetCFAValue().SetOffset(current_sp_bytes_offset_from_cfa); - row_updated = true; - } - } - - else if (add_rsp_pattern_p(stack_offset)) { - current_sp_bytes_offset_from_cfa -= stack_offset; - if (row->GetCFAValue().GetRegisterNumber() == m_lldb_sp_regnum) { - row->GetCFAValue().SetOffset(current_sp_bytes_offset_from_cfa); - row_updated = true; - } - in_epilogue = true; - } - - else if (lea_rsp_pattern_p(stack_offset)) { - current_sp_bytes_offset_from_cfa -= stack_offset; - if (row->GetCFAValue().GetRegisterNumber() == m_lldb_sp_regnum) { - row->GetCFAValue().SetOffset(current_sp_bytes_offset_from_cfa); - row_updated = true; - } - if (stack_offset > 0) - in_epilogue = true; - } - - else if (ret_pattern_p() && prologue_completed_row.get()) { - // Reinstate the saved prologue setup for any instructions - // that come after the ret instruction - - UnwindPlan::Row *newrow = new UnwindPlan::Row; - *newrow = *prologue_completed_row.get(); - row.reset(newrow); - current_sp_bytes_offset_from_cfa = - prologue_completed_sp_bytes_offset_from_cfa; - - saved_registers.clear(); - saved_registers.resize(prologue_completed_saved_registers.size(), false); - for (size_t i = 0; i < prologue_completed_saved_registers.size(); ++i) { - saved_registers[i] = prologue_completed_saved_registers[i]; - } - - in_epilogue = true; - row_updated = true; - } - - // call next instruction - // call 0 - // => pop %ebx - // This is used in i386 programs to get the PIC base address for finding - // global data - else if (call_next_insn_pattern_p()) { - current_sp_bytes_offset_from_cfa += m_wordsize; - if (row->GetCFAValue().GetRegisterNumber() == m_lldb_sp_regnum) { - row->GetCFAValue().SetOffset(current_sp_bytes_offset_from_cfa); - row_updated = true; - } - } - - if (row_updated) { - if (current_func_text_offset + insn_len < m_func_bounds.GetByteSize()) { - row->SetOffset(current_func_text_offset + insn_len); - unwind_plan.AppendRow(row); - // Allocate a new Row, populate it with the existing Row contents. - newrow = new UnwindPlan::Row; - *newrow = *row.get(); - row.reset(newrow); - } - } - - if (in_epilogue == false && row_updated) { - // If we're not in an epilogue sequence, save the updated Row - UnwindPlan::Row *newrow = new UnwindPlan::Row; - *newrow = *row.get(); - prologue_completed_row.reset(newrow); - - prologue_completed_saved_registers.clear(); - prologue_completed_saved_registers.resize(saved_registers.size(), false); - for (size_t i = 0; i < saved_registers.size(); ++i) { - prologue_completed_saved_registers[i] = saved_registers[i]; - } - } - - // We may change the sp value without adding a new Row necessarily -- keep - // track of it either way. - if (in_epilogue == false) { - prologue_completed_sp_bytes_offset_from_cfa = - current_sp_bytes_offset_from_cfa; - } - - m_cur_insn.SetOffset(m_cur_insn.GetOffset() + insn_len); - current_func_text_offset += insn_len; - } - - unwind_plan.SetSourceName("assembly insn profiling"); - unwind_plan.SetSourcedFromCompiler(eLazyBoolNo); - unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolYes); - - return true; -} - -bool AssemblyParse_x86::augment_unwind_plan_from_call_site( - AddressRange &func, UnwindPlan &unwind_plan) { - // Is func address valid? - Address addr_start = func.GetBaseAddress(); - if (!addr_start.IsValid()) - return false; - - // Is original unwind_plan valid? - // unwind_plan should have at least one row which is ABI-default (CFA register - // is sp), - // and another row in mid-function. - if (unwind_plan.GetRowCount() < 2) - return false; - UnwindPlan::RowSP first_row = unwind_plan.GetRowAtIndex(0); - if (first_row->GetOffset() != 0) - return false; - uint32_t cfa_reg = m_exe_ctx.GetThreadPtr() - ->GetRegisterContext() - ->ConvertRegisterKindToRegisterNumber( - unwind_plan.GetRegisterKind(), - first_row->GetCFAValue().GetRegisterNumber()); - if (cfa_reg != m_lldb_sp_regnum || - first_row->GetCFAValue().GetOffset() != m_wordsize) - return false; - - UnwindPlan::RowSP original_last_row = unwind_plan.GetRowForFunctionOffset(-1); - - Target *target = m_exe_ctx.GetTargetPtr(); - m_cur_insn = func.GetBaseAddress(); - uint64_t offset = 0; - int row_id = 1; - bool unwind_plan_updated = false; - UnwindPlan::RowSP row(new UnwindPlan::Row(*first_row)); - - // After a mid-function epilogue we will need to re-insert the original unwind - // rules - // so unwinds work for the remainder of the function. These aren't common - // with clang/gcc - // on x86 but it is possible. - bool reinstate_unwind_state = false; - - while (func.ContainsFileAddress(m_cur_insn)) { - int insn_len; - if (!instruction_length(m_cur_insn, insn_len) || insn_len == 0 || - insn_len > kMaxInstructionByteSize) { - // An unrecognized/junk instruction. - break; - } - const bool prefer_file_cache = true; - Error error; - if (target->ReadMemory(m_cur_insn, prefer_file_cache, m_cur_insn_bytes, - insn_len, error) == static_cast<size_t>(-1)) { - // Error reading the instruction out of the file, stop scanning. - break; - } - - // Advance offsets. - offset += insn_len; - m_cur_insn.SetOffset(m_cur_insn.GetOffset() + insn_len); - - if (reinstate_unwind_state) { - // that was the last instruction of this function - if (func.ContainsFileAddress(m_cur_insn) == false) - continue; - - UnwindPlan::RowSP new_row(new UnwindPlan::Row()); - *new_row = *original_last_row; - new_row->SetOffset(offset); - unwind_plan.AppendRow(new_row); - row.reset(new UnwindPlan::Row()); - *row = *new_row; - reinstate_unwind_state = false; - unwind_plan_updated = true; - continue; - } - - // If we already have one row for this instruction, we can continue. - while (row_id < unwind_plan.GetRowCount() && - unwind_plan.GetRowAtIndex(row_id)->GetOffset() <= offset) { - row_id++; - } - UnwindPlan::RowSP original_row = unwind_plan.GetRowAtIndex(row_id - 1); - if (original_row->GetOffset() == offset) { - *row = *original_row; - continue; - } - - if (row_id == 0) { - // If we are here, compiler didn't generate CFI for prologue. - // This won't happen to GCC or clang. - // In this case, bail out directly. - return false; - } - - // Inspect the instruction to check if we need a new row for it. - cfa_reg = m_exe_ctx.GetThreadPtr() - ->GetRegisterContext() - ->ConvertRegisterKindToRegisterNumber( - unwind_plan.GetRegisterKind(), - row->GetCFAValue().GetRegisterNumber()); - if (cfa_reg == m_lldb_sp_regnum) { - // CFA register is sp. - - // call next instruction - // call 0 - // => pop %ebx - if (call_next_insn_pattern_p()) { - row->SetOffset(offset); - row->GetCFAValue().IncOffset(m_wordsize); - - UnwindPlan::RowSP new_row(new UnwindPlan::Row(*row)); - unwind_plan.InsertRow(new_row); - unwind_plan_updated = true; - continue; - } - - // push/pop register - int regno; - if (push_reg_p(regno)) { - row->SetOffset(offset); - row->GetCFAValue().IncOffset(m_wordsize); - - UnwindPlan::RowSP new_row(new UnwindPlan::Row(*row)); - unwind_plan.InsertRow(new_row); - unwind_plan_updated = true; - continue; - } - if (pop_reg_p(regno)) { - // Technically, this might be a nonvolatile register recover in - // epilogue. - // We should reset RegisterInfo for the register. - // But in practice, previous rule for the register is still valid... - // So we ignore this case. - - row->SetOffset(offset); - row->GetCFAValue().IncOffset(-m_wordsize); - - UnwindPlan::RowSP new_row(new UnwindPlan::Row(*row)); - unwind_plan.InsertRow(new_row); - unwind_plan_updated = true; - continue; - } - - // push imm - if (push_imm_pattern_p()) { - row->SetOffset(offset); - row->GetCFAValue().IncOffset(m_wordsize); - UnwindPlan::RowSP new_row(new UnwindPlan::Row(*row)); - unwind_plan.InsertRow(new_row); - unwind_plan_updated = true; - continue; - } - - // add/sub %rsp/%esp - int amount; - if (add_rsp_pattern_p(amount)) { - row->SetOffset(offset); - row->GetCFAValue().IncOffset(-amount); - - UnwindPlan::RowSP new_row(new UnwindPlan::Row(*row)); - unwind_plan.InsertRow(new_row); - unwind_plan_updated = true; - continue; - } - if (sub_rsp_pattern_p(amount)) { - row->SetOffset(offset); - row->GetCFAValue().IncOffset(amount); - - UnwindPlan::RowSP new_row(new UnwindPlan::Row(*row)); - unwind_plan.InsertRow(new_row); - unwind_plan_updated = true; - continue; - } - - // lea %rsp, [%rsp + $offset] - if (lea_rsp_pattern_p(amount)) { - row->SetOffset(offset); - row->GetCFAValue().IncOffset(-amount); - - UnwindPlan::RowSP new_row(new UnwindPlan::Row(*row)); - unwind_plan.InsertRow(new_row); - unwind_plan_updated = true; - continue; - } - - if (ret_pattern_p()) { - reinstate_unwind_state = true; - continue; - } - } else if (cfa_reg == m_lldb_fp_regnum) { - // CFA register is fp. - - // The only case we care about is epilogue: - // [0x5d] pop %rbp/%ebp - // => [0xc3] ret - if (pop_rbp_pattern_p() || leave_pattern_p()) { - if (target->ReadMemory(m_cur_insn, prefer_file_cache, m_cur_insn_bytes, - 1, error) != static_cast<size_t>(-1) && - ret_pattern_p()) { - row->SetOffset(offset); - row->GetCFAValue().SetIsRegisterPlusOffset( - first_row->GetCFAValue().GetRegisterNumber(), m_wordsize); - - UnwindPlan::RowSP new_row(new UnwindPlan::Row(*row)); - unwind_plan.InsertRow(new_row); - unwind_plan_updated = true; - reinstate_unwind_state = true; - continue; - } - } - } else { - // CFA register is not sp or fp. - - // This must be hand-written assembly. - // Just trust eh_frame and assume we have finished. - break; - } - } - - unwind_plan.SetPlanValidAddressRange(func); - if (unwind_plan_updated) { - std::string unwind_plan_source(unwind_plan.GetSourceName().AsCString()); - unwind_plan_source += " plus augmentation from assembly parsing"; - unwind_plan.SetSourceName(unwind_plan_source.c_str()); - unwind_plan.SetSourcedFromCompiler(eLazyBoolNo); - unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolYes); - } - return true; -} - -/* The "fast unwind plan" is valid for functions that follow the usual - convention of - using the frame pointer register (ebp, rbp), i.e. the function prologue looks - like - push %rbp [0x55] - mov %rsp,%rbp [0x48 0x89 0xe5] (this is a 2-byte insn seq on i386) -*/ - -bool AssemblyParse_x86::get_fast_unwind_plan(AddressRange &func, - UnwindPlan &unwind_plan) { - UnwindPlan::RowSP row(new UnwindPlan::Row); - UnwindPlan::Row::RegisterLocation pc_reginfo; - UnwindPlan::Row::RegisterLocation sp_reginfo; - UnwindPlan::Row::RegisterLocation fp_reginfo; - unwind_plan.SetRegisterKind(eRegisterKindLLDB); - - if (!func.GetBaseAddress().IsValid()) - return false; - - Target *target = m_exe_ctx.GetTargetPtr(); - - uint8_t bytebuf[4]; + std::vector<uint8_t> function_text(func.GetByteSize()); Error error; - const bool prefer_file_cache = true; - if (target->ReadMemory(func.GetBaseAddress(), prefer_file_cache, bytebuf, - sizeof(bytebuf), error) == static_cast<size_t>(-1)) - return false; - - uint8_t i386_prologue[] = {0x55, 0x89, 0xe5}; - uint8_t x86_64_prologue[] = {0x55, 0x48, 0x89, 0xe5}; - int prologue_size; - - if (memcmp(bytebuf, i386_prologue, sizeof(i386_prologue)) == 0) { - prologue_size = sizeof(i386_prologue); - } else if (memcmp(bytebuf, x86_64_prologue, sizeof(x86_64_prologue)) == 0) { - prologue_size = sizeof(x86_64_prologue); - } else { - return false; - } - - pc_reginfo.SetAtCFAPlusOffset(-m_wordsize); - row->SetRegisterInfo(m_lldb_ip_regnum, pc_reginfo); - - sp_reginfo.SetIsCFAPlusOffset(0); - row->SetRegisterInfo(m_lldb_sp_regnum, sp_reginfo); - - // Zero instructions into the function - row->GetCFAValue().SetIsRegisterPlusOffset(m_lldb_sp_regnum, m_wordsize); - row->SetOffset(0); - unwind_plan.AppendRow(row); - UnwindPlan::Row *newrow = new UnwindPlan::Row; - *newrow = *row.get(); - row.reset(newrow); - - // push %rbp has executed - stack moved, rbp now saved - row->GetCFAValue().IncOffset(m_wordsize); - fp_reginfo.SetAtCFAPlusOffset(2 * -m_wordsize); - row->SetRegisterInfo(m_lldb_fp_regnum, fp_reginfo); - row->SetOffset(1); - unwind_plan.AppendRow(row); - - newrow = new UnwindPlan::Row; - *newrow = *row.get(); - row.reset(newrow); - - // mov %rsp, %rbp has executed - row->GetCFAValue().SetIsRegisterPlusOffset(m_lldb_fp_regnum, 2 * m_wordsize); - row->SetOffset(prologue_size); /// 3 or 4 bytes depending on arch - unwind_plan.AppendRow(row); - - newrow = new UnwindPlan::Row; - *newrow = *row.get(); - row.reset(newrow); - - unwind_plan.SetPlanValidAddressRange(func); - unwind_plan.SetSourceName("fast unwind assembly profiling"); - unwind_plan.SetSourcedFromCompiler(eLazyBoolNo); - unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo); - return true; -} - -bool AssemblyParse_x86::find_first_non_prologue_insn(Address &address) { - m_cur_insn = m_func_bounds.GetBaseAddress(); - if (!m_cur_insn.IsValid()) { - return false; + if (process_sp->GetTarget().ReadMemory( + func.GetBaseAddress(), prefer_file_cache, function_text.data(), + func.GetByteSize(), error) == func.GetByteSize()) { + RegisterContextSP reg_ctx(thread.GetRegisterContext()); + m_assembly_inspection_engine->Initialize(reg_ctx); + return m_assembly_inspection_engine->GetNonCallSiteUnwindPlanFromAssembly( + function_text.data(), func.GetByteSize(), func, unwind_plan); } - - const bool prefer_file_cache = true; - Target *target = m_exe_ctx.GetTargetPtr(); - while (m_func_bounds.ContainsFileAddress(m_cur_insn)) { - Error error; - int insn_len, offset, regno; - if (!instruction_length(m_cur_insn, insn_len) || - insn_len > kMaxInstructionByteSize || insn_len == 0) { - // An error parsing the instruction, i.e. probably data/garbage - stop - // scanning - break; - } - if (target->ReadMemory(m_cur_insn, prefer_file_cache, m_cur_insn_bytes, - insn_len, error) == static_cast<size_t>(-1)) { - // Error reading the instruction out of the file, stop scanning - break; - } - - if (push_rbp_pattern_p() || mov_rsp_rbp_pattern_p() || - sub_rsp_pattern_p(offset) || push_reg_p(regno) || - mov_reg_to_local_stack_frame_p(regno, offset) || - (lea_rsp_pattern_p(offset) && offset < 0)) { - m_cur_insn.SetOffset(m_cur_insn.GetOffset() + insn_len); - continue; - } - - // Unknown non-prologue instruction - stop scanning - break; - } - - address = m_cur_insn; - return true; -} - -//----------------------------------------------------------------------------------------------- -// UnwindAssemblyParser_x86 method definitions -//----------------------------------------------------------------------------------------------- - -UnwindAssembly_x86::UnwindAssembly_x86(const ArchSpec &arch, int cpu) - : lldb_private::UnwindAssembly(arch), m_cpu(cpu), m_arch(arch) {} - -UnwindAssembly_x86::~UnwindAssembly_x86() {} - -bool UnwindAssembly_x86::GetNonCallSiteUnwindPlanFromAssembly( - AddressRange &func, Thread &thread, UnwindPlan &unwind_plan) { - ExecutionContext exe_ctx(thread.shared_from_this()); - AssemblyParse_x86 asm_parse(exe_ctx, m_cpu, m_arch, func); - return asm_parse.get_non_call_site_unwind_plan(unwind_plan); + return false; } bool UnwindAssembly_x86::AugmentUnwindPlanFromCallSite( @@ -1235,9 +75,10 @@ bool UnwindAssembly_x86::AugmentUnwindPlanFromCallSite( int wordsize = 8; ProcessSP process_sp(thread.GetProcess()); - if (process_sp) { - wordsize = process_sp->GetTarget().GetArchitecture().GetAddressByteSize(); - } + if (process_sp.get() == nullptr) + return false; + + wordsize = process_sp->GetTarget().GetArchitecture().GetAddressByteSize(); RegisterNumber sp_regnum(thread, eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP); @@ -1314,9 +155,21 @@ bool UnwindAssembly_x86::AugmentUnwindPlanFromCallSite( } if (do_augment_unwindplan) { - ExecutionContext exe_ctx(thread.shared_from_this()); - AssemblyParse_x86 asm_parse(exe_ctx, m_cpu, m_arch, func); - return asm_parse.augment_unwind_plan_from_call_site(func, unwind_plan); + if (!func.GetBaseAddress().IsValid() || func.GetByteSize() == 0) + return false; + if (m_assembly_inspection_engine == nullptr) + return false; + const bool prefer_file_cache = true; + std::vector<uint8_t> function_text(func.GetByteSize()); + Error error; + if (process_sp->GetTarget().ReadMemory( + func.GetBaseAddress(), prefer_file_cache, function_text.data(), + func.GetByteSize(), error) == func.GetByteSize()) { + RegisterContextSP reg_ctx(thread.GetRegisterContext()); + m_assembly_inspection_engine->Initialize(reg_ctx); + return m_assembly_inspection_engine->AugmentUnwindPlanFromCallSite( + function_text.data(), func.GetByteSize(), func, unwind_plan, reg_ctx); + } } return false; @@ -1362,16 +215,38 @@ bool UnwindAssembly_x86::GetFastUnwindPlan(AddressRange &func, Thread &thread, bool UnwindAssembly_x86::FirstNonPrologueInsn( AddressRange &func, const ExecutionContext &exe_ctx, Address &first_non_prologue_insn) { - AssemblyParse_x86 asm_parse(exe_ctx, m_cpu, m_arch, func); - return asm_parse.find_first_non_prologue_insn(first_non_prologue_insn); + + if (!func.GetBaseAddress().IsValid()) + return false; + + Target *target = exe_ctx.GetTargetPtr(); + if (target == nullptr) + return false; + + if (m_assembly_inspection_engine == nullptr) + return false; + + const bool prefer_file_cache = true; + std::vector<uint8_t> function_text(func.GetByteSize()); + Error error; + if (target->ReadMemory(func.GetBaseAddress(), prefer_file_cache, + function_text.data(), func.GetByteSize(), + error) == func.GetByteSize()) { + size_t offset; + if (m_assembly_inspection_engine->FindFirstNonPrologueInstruction( + function_text.data(), func.GetByteSize(), offset)) { + first_non_prologue_insn = func.GetBaseAddress(); + first_non_prologue_insn.Slide(offset); + } + return true; + } + return false; } UnwindAssembly *UnwindAssembly_x86::CreateInstance(const ArchSpec &arch) { const llvm::Triple::ArchType cpu = arch.GetMachine(); - if (cpu == llvm::Triple::x86) - return new UnwindAssembly_x86(arch, k_i386); - else if (cpu == llvm::Triple::x86_64) - return new UnwindAssembly_x86(arch, k_x86_64); + if (cpu == llvm::Triple::x86 || cpu == llvm::Triple::x86_64) + return new UnwindAssembly_x86(arch); return NULL; } |
