//===-- IRInterpreter.cpp -------------------------------------------------===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// #include "lldb/Expression/IRInterpreter.h" #include "lldb/Core/Module.h" #include "lldb/Core/ModuleSpec.h" #include "lldb/Core/ValueObject.h" #include "lldb/Expression/DiagnosticManager.h" #include "lldb/Expression/IRExecutionUnit.h" #include "lldb/Expression/IRMemoryMap.h" #include "lldb/Utility/ConstString.h" #include "lldb/Utility/DataExtractor.h" #include "lldb/Utility/Endian.h" #include "lldb/Utility/Log.h" #include "lldb/Utility/Scalar.h" #include "lldb/Utility/Status.h" #include "lldb/Utility/StreamString.h" #include "lldb/Target/ABI.h" #include "lldb/Target/ExecutionContext.h" #include "lldb/Target/Target.h" #include "lldb/Target/Thread.h" #include "lldb/Target/ThreadPlan.h" #include "lldb/Target/ThreadPlanCallFunctionUsingABI.h" #include "llvm/IR/Constants.h" #include "llvm/IR/DataLayout.h" #include "llvm/IR/Function.h" #include "llvm/IR/Instructions.h" #include "llvm/IR/Intrinsics.h" #include "llvm/IR/LLVMContext.h" #include "llvm/IR/Module.h" #include "llvm/IR/Operator.h" #include "llvm/Support/raw_ostream.h" #include using namespace llvm; static std::string PrintValue(const Value *value, bool truncate = false) { std::string s; raw_string_ostream rso(s); value->print(rso); rso.flush(); if (truncate) s.resize(s.length() - 1); size_t offset; while ((offset = s.find('\n')) != s.npos) s.erase(offset, 1); while (s[0] == ' ' || s[0] == '\t') s.erase(0, 1); return s; } static std::string PrintType(const Type *type, bool truncate = false) { std::string s; raw_string_ostream rso(s); type->print(rso); rso.flush(); if (truncate) s.resize(s.length() - 1); return s; } static bool CanIgnoreCall(const CallInst *call) { const llvm::Function *called_function = call->getCalledFunction(); if (!called_function) return false; if (called_function->isIntrinsic()) { switch (called_function->getIntrinsicID()) { default: break; case llvm::Intrinsic::dbg_declare: case llvm::Intrinsic::dbg_value: return true; } } return false; } class InterpreterStackFrame { public: typedef std::map ValueMap; ValueMap m_values; DataLayout &m_target_data; lldb_private::IRExecutionUnit &m_execution_unit; const BasicBlock *m_bb; const BasicBlock *m_prev_bb; BasicBlock::const_iterator m_ii; BasicBlock::const_iterator m_ie; lldb::addr_t m_frame_process_address; size_t m_frame_size; lldb::addr_t m_stack_pointer; lldb::ByteOrder m_byte_order; size_t m_addr_byte_size; InterpreterStackFrame(DataLayout &target_data, lldb_private::IRExecutionUnit &execution_unit, lldb::addr_t stack_frame_bottom, lldb::addr_t stack_frame_top) : m_target_data(target_data), m_execution_unit(execution_unit), m_bb(nullptr), m_prev_bb(nullptr) { m_byte_order = (target_data.isLittleEndian() ? lldb::eByteOrderLittle : lldb::eByteOrderBig); m_addr_byte_size = (target_data.getPointerSize(0)); m_frame_process_address = stack_frame_bottom; m_frame_size = stack_frame_top - stack_frame_bottom; m_stack_pointer = stack_frame_top; } ~InterpreterStackFrame() {} void Jump(const BasicBlock *bb) { m_prev_bb = m_bb; m_bb = bb; m_ii = m_bb->begin(); m_ie = m_bb->end(); } std::string SummarizeValue(const Value *value) { lldb_private::StreamString ss; ss.Printf("%s", PrintValue(value).c_str()); ValueMap::iterator i = m_values.find(value); if (i != m_values.end()) { lldb::addr_t addr = i->second; ss.Printf(" 0x%llx", (unsigned long long)addr); } return std::string(ss.GetString()); } bool AssignToMatchType(lldb_private::Scalar &scalar, llvm::APInt value, Type *type) { size_t type_size = m_target_data.getTypeStoreSize(type); if (type_size > 8) return false; if (type_size != 1) type_size = PowerOf2Ceil(type_size); scalar = value.zextOrTrunc(type_size * 8); return true; } bool EvaluateValue(lldb_private::Scalar &scalar, const Value *value, Module &module) { const Constant *constant = dyn_cast(value); if (constant) { APInt value_apint; if (!ResolveConstantValue(value_apint, constant)) return false; return AssignToMatchType(scalar, value_apint, value->getType()); } lldb::addr_t process_address = ResolveValue(value, module); size_t value_size = m_target_data.getTypeStoreSize(value->getType()); lldb_private::DataExtractor value_extractor; lldb_private::Status extract_error; m_execution_unit.GetMemoryData(value_extractor, process_address, value_size, extract_error); if (!extract_error.Success()) return false; lldb::offset_t offset = 0; if (value_size <= 8) { uint64_t u64value = value_extractor.GetMaxU64(&offset, value_size); return AssignToMatchType(scalar, llvm::APInt(64, u64value), value->getType()); } return false; } bool AssignValue(const Value *value, lldb_private::Scalar scalar, Module &module) { lldb::addr_t process_address = ResolveValue(value, module); if (process_address == LLDB_INVALID_ADDRESS) return false; lldb_private::Scalar cast_scalar; scalar.MakeUnsigned(); if (!AssignToMatchType(cast_scalar, scalar.UInt128(llvm::APInt()), value->getType())) return false; size_t value_byte_size = m_target_data.getTypeStoreSize(value->getType()); lldb_private::DataBufferHeap buf(value_byte_size, 0); lldb_private::Status get_data_error; if (!cast_scalar.GetAsMemoryData(buf.GetBytes(), buf.GetByteSize(), m_byte_order, get_data_error)) return false; lldb_private::Status write_error; m_execution_unit.WriteMemory(process_address, buf.GetBytes(), buf.GetByteSize(), write_error); return write_error.Success(); } bool ResolveConstantValue(APInt &value, const Constant *constant) { switch (constant->getValueID()) { default: break; case Value::FunctionVal: if (const Function *constant_func = dyn_cast(constant)) { lldb_private::ConstString name(constant_func->getName()); bool missing_weak = false; lldb::addr_t addr = m_execution_unit.FindSymbol(name, missing_weak); if (addr == LLDB_INVALID_ADDRESS || missing_weak) return false; value = APInt(m_target_data.getPointerSizeInBits(), addr); return true; } break; case Value::ConstantIntVal: if (const ConstantInt *constant_int = dyn_cast(constant)) { value = constant_int->getValue(); return true; } break; case Value::ConstantFPVal: if (const ConstantFP *constant_fp = dyn_cast(constant)) { value = constant_fp->getValueAPF().bitcastToAPInt(); return true; } break; case Value::ConstantExprVal: if (const ConstantExpr *constant_expr = dyn_cast(constant)) { switch (constant_expr->getOpcode()) { default: return false; case Instruction::IntToPtr: case Instruction::PtrToInt: case Instruction::BitCast: return ResolveConstantValue(value, constant_expr->getOperand(0)); case Instruction::GetElementPtr: { ConstantExpr::const_op_iterator op_cursor = constant_expr->op_begin(); ConstantExpr::const_op_iterator op_end = constant_expr->op_end(); Constant *base = dyn_cast(*op_cursor); if (!base) return false; if (!ResolveConstantValue(value, base)) return false; op_cursor++; if (op_cursor == op_end) return true; // no offset to apply! SmallVector indices(op_cursor, op_end); Type *src_elem_ty = cast(constant_expr)->getSourceElementType(); uint64_t offset = m_target_data.getIndexedOffsetInType(src_elem_ty, indices); const bool is_signed = true; value += APInt(value.getBitWidth(), offset, is_signed); return true; } } } break; case Value::ConstantPointerNullVal: if (isa(constant)) { value = APInt(m_target_data.getPointerSizeInBits(), 0); return true; } break; } return false; } bool MakeArgument(const Argument *value, uint64_t address) { lldb::addr_t data_address = Malloc(value->getType()); if (data_address == LLDB_INVALID_ADDRESS) return false; lldb_private::Status write_error; m_execution_unit.WritePointerToMemory(data_address, address, write_error); if (!write_error.Success()) { lldb_private::Status free_error; m_execution_unit.Free(data_address, free_error); return false; } m_values[value] = data_address; lldb_private::Log *log( lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS)); if (log) { LLDB_LOGF(log, "Made an allocation for argument %s", PrintValue(value).c_str()); LLDB_LOGF(log, " Data region : %llx", (unsigned long long)address); LLDB_LOGF(log, " Ref region : %llx", (unsigned long long)data_address); } return true; } bool ResolveConstant(lldb::addr_t process_address, const Constant *constant) { APInt resolved_value; if (!ResolveConstantValue(resolved_value, constant)) return false; size_t constant_size = m_target_data.getTypeStoreSize(constant->getType()); lldb_private::DataBufferHeap buf(constant_size, 0); lldb_private::Status get_data_error; lldb_private::Scalar resolved_scalar( resolved_value.zextOrTrunc(llvm::NextPowerOf2(constant_size) * 8)); if (!resolved_scalar.GetAsMemoryData(buf.GetBytes(), buf.GetByteSize(), m_byte_order, get_data_error)) return false; lldb_private::Status write_error; m_execution_unit.WriteMemory(process_address, buf.GetBytes(), buf.GetByteSize(), write_error); return write_error.Success(); } lldb::addr_t Malloc(size_t size, uint8_t byte_alignment) { lldb::addr_t ret = m_stack_pointer; ret -= size; ret -= (ret % byte_alignment); if (ret < m_frame_process_address) return LLDB_INVALID_ADDRESS; m_stack_pointer = ret; return ret; } lldb::addr_t Malloc(llvm::Type *type) { lldb_private::Status alloc_error; return Malloc(m_target_data.getTypeAllocSize(type), m_target_data.getPrefTypeAlignment(type)); } std::string PrintData(lldb::addr_t addr, llvm::Type *type) { size_t length = m_target_data.getTypeStoreSize(type); lldb_private::DataBufferHeap buf(length, 0); lldb_private::Status read_error; m_execution_unit.ReadMemory(buf.GetBytes(), addr, length, read_error); if (!read_error.Success()) return std::string(""); lldb_private::StreamString ss; for (size_t i = 0; i < length; i++) { if ((!(i & 0xf)) && i) ss.Printf("%02hhx - ", buf.GetBytes()[i]); else ss.Printf("%02hhx ", buf.GetBytes()[i]); } return std::string(ss.GetString()); } lldb::addr_t ResolveValue(const Value *value, Module &module) { ValueMap::iterator i = m_values.find(value); if (i != m_values.end()) return i->second; // Fall back and allocate space [allocation type Alloca] lldb::addr_t data_address = Malloc(value->getType()); if (const Constant *constant = dyn_cast(value)) { if (!ResolveConstant(data_address, constant)) { lldb_private::Status free_error; m_execution_unit.Free(data_address, free_error); return LLDB_INVALID_ADDRESS; } } m_values[value] = data_address; return data_address; } }; static const char *unsupported_opcode_error = "Interpreter doesn't handle one of the expression's opcodes"; static const char *unsupported_operand_error = "Interpreter doesn't handle one of the expression's operands"; static const char *interpreter_internal_error = "Interpreter encountered an internal error"; static const char *bad_value_error = "Interpreter couldn't resolve a value during execution"; static const char *memory_allocation_error = "Interpreter couldn't allocate memory"; static const char *memory_write_error = "Interpreter couldn't write to memory"; static const char *memory_read_error = "Interpreter couldn't read from memory"; static const char *infinite_loop_error = "Interpreter ran for too many cycles"; static const char *too_many_functions_error = "Interpreter doesn't handle modules with multiple function bodies."; static bool CanResolveConstant(llvm::Constant *constant) { switch (constant->getValueID()) { default: return false; case Value::ConstantIntVal: case Value::ConstantFPVal: case Value::FunctionVal: return true; case Value::ConstantExprVal: if (const ConstantExpr *constant_expr = dyn_cast(constant)) { switch (constant_expr->getOpcode()) { default: return false; case Instruction::IntToPtr: case Instruction::PtrToInt: case Instruction::BitCast: return CanResolveConstant(constant_expr->getOperand(0)); case Instruction::GetElementPtr: { ConstantExpr::const_op_iterator op_cursor = constant_expr->op_begin(); Constant *base = dyn_cast(*op_cursor); if (!base) return false; return CanResolveConstant(base); } } } else { return false; } case Value::ConstantPointerNullVal: return true; } } bool IRInterpreter::CanInterpret(llvm::Module &module, llvm::Function &function, lldb_private::Status &error, const bool support_function_calls) { lldb_private::Log *log( lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS)); bool saw_function_with_body = false; for (Function &f : module) { if (f.begin() != f.end()) { if (saw_function_with_body) { LLDB_LOGF(log, "More than one function in the module has a body"); error.SetErrorToGenericError(); error.SetErrorString(too_many_functions_error); return false; } saw_function_with_body = true; } } for (BasicBlock &bb : function) { for (Instruction &ii : bb) { switch (ii.getOpcode()) { default: { LLDB_LOGF(log, "Unsupported instruction: %s", PrintValue(&ii).c_str()); error.SetErrorToGenericError(); error.SetErrorString(unsupported_opcode_error); return false; } case Instruction::Add: case Instruction::Alloca: case Instruction::BitCast: case Instruction::Br: case Instruction::PHI: break; case Instruction::Call: { CallInst *call_inst = dyn_cast(&ii); if (!call_inst) { error.SetErrorToGenericError(); error.SetErrorString(interpreter_internal_error); return false; } if (!CanIgnoreCall(call_inst) && !support_function_calls) { LLDB_LOGF(log, "Unsupported instruction: %s", PrintValue(&ii).c_str()); error.SetErrorToGenericError(); error.SetErrorString(unsupported_opcode_error); return false; } } break; case Instruction::GetElementPtr: break; case Instruction::ICmp: { ICmpInst *icmp_inst = dyn_cast(&ii); if (!icmp_inst) { error.SetErrorToGenericError(); error.SetErrorString(interpreter_internal_error); return false; } switch (icmp_inst->getPredicate()) { default: { LLDB_LOGF(log, "Unsupported ICmp predicate: %s", PrintValue(&ii).c_str()); error.SetErrorToGenericError(); error.SetErrorString(unsupported_opcode_error); return false; } case CmpInst::ICMP_EQ: case CmpInst::ICMP_NE: case CmpInst::ICMP_UGT: case CmpInst::ICMP_UGE: case CmpInst::ICMP_ULT: case CmpInst::ICMP_ULE: case CmpInst::ICMP_SGT: case CmpInst::ICMP_SGE: case CmpInst::ICMP_SLT: case CmpInst::ICMP_SLE: break; } } break; case Instruction::And: case Instruction::AShr: case Instruction::IntToPtr: case Instruction::PtrToInt: case Instruction::Load: case Instruction::LShr: case Instruction::Mul: case Instruction::Or: case Instruction::Ret: case Instruction::SDiv: case Instruction::SExt: case Instruction::Shl: case Instruction::SRem: case Instruction::Store: case Instruction::Sub: case Instruction::Trunc: case Instruction::UDiv: case Instruction::URem: case Instruction::Xor: case Instruction::ZExt: break; } for (unsigned oi = 0, oe = ii.getNumOperands(); oi != oe; ++oi) { Value *operand = ii.getOperand(oi); Type *operand_type = operand->getType(); switch (operand_type->getTypeID()) { default: break; case Type::FixedVectorTyID: case Type::ScalableVectorTyID: { LLDB_LOGF(log, "Unsupported operand type: %s", PrintType(operand_type).c_str()); error.SetErrorString(unsupported_operand_error); return false; } } // The IR interpreter currently doesn't know about // 128-bit integers. As they're not that frequent, // we can just fall back to the JIT rather than // choking. if (operand_type->getPrimitiveSizeInBits() > 64) { LLDB_LOGF(log, "Unsupported operand type: %s", PrintType(operand_type).c_str()); error.SetErrorString(unsupported_operand_error); return false; } if (Constant *constant = llvm::dyn_cast(operand)) { if (!CanResolveConstant(constant)) { LLDB_LOGF(log, "Unsupported constant: %s", PrintValue(constant).c_str()); error.SetErrorString(unsupported_operand_error); return false; } } } } } return true; } bool IRInterpreter::Interpret(llvm::Module &module, llvm::Function &function, llvm::ArrayRef args, lldb_private::IRExecutionUnit &execution_unit, lldb_private::Status &error, lldb::addr_t stack_frame_bottom, lldb::addr_t stack_frame_top, lldb_private::ExecutionContext &exe_ctx) { lldb_private::Log *log( lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS)); if (log) { std::string s; raw_string_ostream oss(s); module.print(oss, nullptr); oss.flush(); LLDB_LOGF(log, "Module as passed in to IRInterpreter::Interpret: \n\"%s\"", s.c_str()); } DataLayout data_layout(&module); InterpreterStackFrame frame(data_layout, execution_unit, stack_frame_bottom, stack_frame_top); if (frame.m_frame_process_address == LLDB_INVALID_ADDRESS) { error.SetErrorString("Couldn't allocate stack frame"); } int arg_index = 0; for (llvm::Function::arg_iterator ai = function.arg_begin(), ae = function.arg_end(); ai != ae; ++ai, ++arg_index) { if (args.size() <= static_cast(arg_index)) { error.SetErrorString("Not enough arguments passed in to function"); return false; } lldb::addr_t ptr = args[arg_index]; frame.MakeArgument(&*ai, ptr); } uint32_t num_insts = 0; frame.Jump(&function.front()); while (frame.m_ii != frame.m_ie && (++num_insts < 4096)) { const Instruction *inst = &*frame.m_ii; LLDB_LOGF(log, "Interpreting %s", PrintValue(inst).c_str()); switch (inst->getOpcode()) { default: break; case Instruction::Add: case Instruction::Sub: case Instruction::Mul: case Instruction::SDiv: case Instruction::UDiv: case Instruction::SRem: case Instruction::URem: case Instruction::Shl: case Instruction::LShr: case Instruction::AShr: case Instruction::And: case Instruction::Or: case Instruction::Xor: { const BinaryOperator *bin_op = dyn_cast(inst); if (!bin_op) { LLDB_LOGF( log, "getOpcode() returns %s, but instruction is not a BinaryOperator", inst->getOpcodeName()); error.SetErrorToGenericError(); error.SetErrorString(interpreter_internal_error); return false; } Value *lhs = inst->getOperand(0); Value *rhs = inst->getOperand(1); lldb_private::Scalar L; lldb_private::Scalar R; if (!frame.EvaluateValue(L, lhs, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(lhs).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } if (!frame.EvaluateValue(R, rhs, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(rhs).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } lldb_private::Scalar result; switch (inst->getOpcode()) { default: break; case Instruction::Add: result = L + R; break; case Instruction::Mul: result = L * R; break; case Instruction::Sub: result = L - R; break; case Instruction::SDiv: L.MakeSigned(); R.MakeSigned(); result = L / R; break; case Instruction::UDiv: L.MakeUnsigned(); R.MakeUnsigned(); result = L / R; break; case Instruction::SRem: L.MakeSigned(); R.MakeSigned(); result = L % R; break; case Instruction::URem: L.MakeUnsigned(); R.MakeUnsigned(); result = L % R; break; case Instruction::Shl: result = L << R; break; case Instruction::AShr: result = L >> R; break; case Instruction::LShr: result = L; result.ShiftRightLogical(R); break; case Instruction::And: result = L & R; break; case Instruction::Or: result = L | R; break; case Instruction::Xor: result = L ^ R; break; } frame.AssignValue(inst, result, module); if (log) { LLDB_LOGF(log, "Interpreted a %s", inst->getOpcodeName()); LLDB_LOGF(log, " L : %s", frame.SummarizeValue(lhs).c_str()); LLDB_LOGF(log, " R : %s", frame.SummarizeValue(rhs).c_str()); LLDB_LOGF(log, " = : %s", frame.SummarizeValue(inst).c_str()); } } break; case Instruction::Alloca: { const AllocaInst *alloca_inst = cast(inst); if (alloca_inst->isArrayAllocation()) { LLDB_LOGF(log, "AllocaInsts are not handled if isArrayAllocation() is true"); error.SetErrorToGenericError(); error.SetErrorString(unsupported_opcode_error); return false; } // The semantics of Alloca are: // Create a region R of virtual memory of type T, backed by a data // buffer // Create a region P of virtual memory of type T*, backed by a data // buffer // Write the virtual address of R into P Type *T = alloca_inst->getAllocatedType(); Type *Tptr = alloca_inst->getType(); lldb::addr_t R = frame.Malloc(T); if (R == LLDB_INVALID_ADDRESS) { LLDB_LOGF(log, "Couldn't allocate memory for an AllocaInst"); error.SetErrorToGenericError(); error.SetErrorString(memory_allocation_error); return false; } lldb::addr_t P = frame.Malloc(Tptr); if (P == LLDB_INVALID_ADDRESS) { LLDB_LOGF(log, "Couldn't allocate the result pointer for an AllocaInst"); error.SetErrorToGenericError(); error.SetErrorString(memory_allocation_error); return false; } lldb_private::Status write_error; execution_unit.WritePointerToMemory(P, R, write_error); if (!write_error.Success()) { LLDB_LOGF(log, "Couldn't write the result pointer for an AllocaInst"); error.SetErrorToGenericError(); error.SetErrorString(memory_write_error); lldb_private::Status free_error; execution_unit.Free(P, free_error); execution_unit.Free(R, free_error); return false; } frame.m_values[alloca_inst] = P; if (log) { LLDB_LOGF(log, "Interpreted an AllocaInst"); LLDB_LOGF(log, " R : 0x%" PRIx64, R); LLDB_LOGF(log, " P : 0x%" PRIx64, P); } } break; case Instruction::BitCast: case Instruction::ZExt: { const CastInst *cast_inst = cast(inst); Value *source = cast_inst->getOperand(0); lldb_private::Scalar S; if (!frame.EvaluateValue(S, source, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(source).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } frame.AssignValue(inst, S, module); } break; case Instruction::SExt: { const CastInst *cast_inst = cast(inst); Value *source = cast_inst->getOperand(0); lldb_private::Scalar S; if (!frame.EvaluateValue(S, source, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(source).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } S.MakeSigned(); lldb_private::Scalar S_signextend(S.SLongLong()); frame.AssignValue(inst, S_signextend, module); } break; case Instruction::Br: { const BranchInst *br_inst = cast(inst); if (br_inst->isConditional()) { Value *condition = br_inst->getCondition(); lldb_private::Scalar C; if (!frame.EvaluateValue(C, condition, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(condition).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } if (!C.IsZero()) frame.Jump(br_inst->getSuccessor(0)); else frame.Jump(br_inst->getSuccessor(1)); if (log) { LLDB_LOGF(log, "Interpreted a BrInst with a condition"); LLDB_LOGF(log, " cond : %s", frame.SummarizeValue(condition).c_str()); } } else { frame.Jump(br_inst->getSuccessor(0)); if (log) { LLDB_LOGF(log, "Interpreted a BrInst with no condition"); } } } continue; case Instruction::PHI: { const PHINode *phi_inst = cast(inst); if (!frame.m_prev_bb) { LLDB_LOGF(log, "Encountered PHI node without having jumped from another " "basic block"); error.SetErrorToGenericError(); error.SetErrorString(interpreter_internal_error); return false; } Value *value = phi_inst->getIncomingValueForBlock(frame.m_prev_bb); lldb_private::Scalar result; if (!frame.EvaluateValue(result, value, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(value).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } frame.AssignValue(inst, result, module); if (log) { LLDB_LOGF(log, "Interpreted a %s", inst->getOpcodeName()); LLDB_LOGF(log, " Incoming value : %s", frame.SummarizeValue(value).c_str()); } } break; case Instruction::GetElementPtr: { const GetElementPtrInst *gep_inst = cast(inst); const Value *pointer_operand = gep_inst->getPointerOperand(); Type *src_elem_ty = gep_inst->getSourceElementType(); lldb_private::Scalar P; if (!frame.EvaluateValue(P, pointer_operand, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(pointer_operand).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } typedef SmallVector IndexVector; typedef IndexVector::iterator IndexIterator; SmallVector indices(gep_inst->idx_begin(), gep_inst->idx_end()); SmallVector const_indices; for (IndexIterator ii = indices.begin(), ie = indices.end(); ii != ie; ++ii) { ConstantInt *constant_index = dyn_cast(*ii); if (!constant_index) { lldb_private::Scalar I; if (!frame.EvaluateValue(I, *ii, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(*ii).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } LLDB_LOGF(log, "Evaluated constant index %s as %llu", PrintValue(*ii).c_str(), I.ULongLong(LLDB_INVALID_ADDRESS)); constant_index = cast(ConstantInt::get( (*ii)->getType(), I.ULongLong(LLDB_INVALID_ADDRESS))); } const_indices.push_back(constant_index); } uint64_t offset = data_layout.getIndexedOffsetInType(src_elem_ty, const_indices); lldb_private::Scalar Poffset = P + offset; frame.AssignValue(inst, Poffset, module); if (log) { LLDB_LOGF(log, "Interpreted a GetElementPtrInst"); LLDB_LOGF(log, " P : %s", frame.SummarizeValue(pointer_operand).c_str()); LLDB_LOGF(log, " Poffset : %s", frame.SummarizeValue(inst).c_str()); } } break; case Instruction::ICmp: { const ICmpInst *icmp_inst = cast(inst); CmpInst::Predicate predicate = icmp_inst->getPredicate(); Value *lhs = inst->getOperand(0); Value *rhs = inst->getOperand(1); lldb_private::Scalar L; lldb_private::Scalar R; if (!frame.EvaluateValue(L, lhs, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(lhs).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } if (!frame.EvaluateValue(R, rhs, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(rhs).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } lldb_private::Scalar result; switch (predicate) { default: return false; case CmpInst::ICMP_EQ: result = (L == R); break; case CmpInst::ICMP_NE: result = (L != R); break; case CmpInst::ICMP_UGT: L.MakeUnsigned(); R.MakeUnsigned(); result = (L > R); break; case CmpInst::ICMP_UGE: L.MakeUnsigned(); R.MakeUnsigned(); result = (L >= R); break; case CmpInst::ICMP_ULT: L.MakeUnsigned(); R.MakeUnsigned(); result = (L < R); break; case CmpInst::ICMP_ULE: L.MakeUnsigned(); R.MakeUnsigned(); result = (L <= R); break; case CmpInst::ICMP_SGT: L.MakeSigned(); R.MakeSigned(); result = (L > R); break; case CmpInst::ICMP_SGE: L.MakeSigned(); R.MakeSigned(); result = (L >= R); break; case CmpInst::ICMP_SLT: L.MakeSigned(); R.MakeSigned(); result = (L < R); break; case CmpInst::ICMP_SLE: L.MakeSigned(); R.MakeSigned(); result = (L <= R); break; } frame.AssignValue(inst, result, module); if (log) { LLDB_LOGF(log, "Interpreted an ICmpInst"); LLDB_LOGF(log, " L : %s", frame.SummarizeValue(lhs).c_str()); LLDB_LOGF(log, " R : %s", frame.SummarizeValue(rhs).c_str()); LLDB_LOGF(log, " = : %s", frame.SummarizeValue(inst).c_str()); } } break; case Instruction::IntToPtr: { const IntToPtrInst *int_to_ptr_inst = cast(inst); Value *src_operand = int_to_ptr_inst->getOperand(0); lldb_private::Scalar I; if (!frame.EvaluateValue(I, src_operand, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(src_operand).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } frame.AssignValue(inst, I, module); if (log) { LLDB_LOGF(log, "Interpreted an IntToPtr"); LLDB_LOGF(log, " Src : %s", frame.SummarizeValue(src_operand).c_str()); LLDB_LOGF(log, " = : %s", frame.SummarizeValue(inst).c_str()); } } break; case Instruction::PtrToInt: { const PtrToIntInst *ptr_to_int_inst = cast(inst); Value *src_operand = ptr_to_int_inst->getOperand(0); lldb_private::Scalar I; if (!frame.EvaluateValue(I, src_operand, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(src_operand).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } frame.AssignValue(inst, I, module); if (log) { LLDB_LOGF(log, "Interpreted a PtrToInt"); LLDB_LOGF(log, " Src : %s", frame.SummarizeValue(src_operand).c_str()); LLDB_LOGF(log, " = : %s", frame.SummarizeValue(inst).c_str()); } } break; case Instruction::Trunc: { const TruncInst *trunc_inst = cast(inst); Value *src_operand = trunc_inst->getOperand(0); lldb_private::Scalar I; if (!frame.EvaluateValue(I, src_operand, module)) { LLDB_LOGF(log, "Couldn't evaluate %s", PrintValue(src_operand).c_str()); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } frame.AssignValue(inst, I, module); if (log) { LLDB_LOGF(log, "Interpreted a Trunc"); LLDB_LOGF(log, " Src : %s", frame.SummarizeValue(src_operand).c_str()); LLDB_LOGF(log, " = : %s", frame.SummarizeValue(inst).c_str()); } } break; case Instruction::Load: { const LoadInst *load_inst = cast(inst); // The semantics of Load are: // Create a region D that will contain the loaded data // Resolve the region P containing a pointer // Dereference P to get the region R that the data should be loaded from // Transfer a unit of type type(D) from R to D const Value *pointer_operand = load_inst->getPointerOperand(); Type *pointer_ty = pointer_operand->getType(); PointerType *pointer_ptr_ty = dyn_cast(pointer_ty); if (!pointer_ptr_ty) { LLDB_LOGF(log, "getPointerOperand()->getType() is not a PointerType"); error.SetErrorToGenericError(); error.SetErrorString(interpreter_internal_error); return false; } Type *target_ty = pointer_ptr_ty->getElementType(); lldb::addr_t D = frame.ResolveValue(load_inst, module); lldb::addr_t P = frame.ResolveValue(pointer_operand, module); if (D == LLDB_INVALID_ADDRESS) { LLDB_LOGF(log, "LoadInst's value doesn't resolve to anything"); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } if (P == LLDB_INVALID_ADDRESS) { LLDB_LOGF(log, "LoadInst's pointer doesn't resolve to anything"); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } lldb::addr_t R; lldb_private::Status read_error; execution_unit.ReadPointerFromMemory(&R, P, read_error); if (!read_error.Success()) { LLDB_LOGF(log, "Couldn't read the address to be loaded for a LoadInst"); error.SetErrorToGenericError(); error.SetErrorString(memory_read_error); return false; } size_t target_size = data_layout.getTypeStoreSize(target_ty); lldb_private::DataBufferHeap buffer(target_size, 0); read_error.Clear(); execution_unit.ReadMemory(buffer.GetBytes(), R, buffer.GetByteSize(), read_error); if (!read_error.Success()) { LLDB_LOGF(log, "Couldn't read from a region on behalf of a LoadInst"); error.SetErrorToGenericError(); error.SetErrorString(memory_read_error); return false; } lldb_private::Status write_error; execution_unit.WriteMemory(D, buffer.GetBytes(), buffer.GetByteSize(), write_error); if (!write_error.Success()) { LLDB_LOGF(log, "Couldn't write to a region on behalf of a LoadInst"); error.SetErrorToGenericError(); error.SetErrorString(memory_read_error); return false; } if (log) { LLDB_LOGF(log, "Interpreted a LoadInst"); LLDB_LOGF(log, " P : 0x%" PRIx64, P); LLDB_LOGF(log, " R : 0x%" PRIx64, R); LLDB_LOGF(log, " D : 0x%" PRIx64, D); } } break; case Instruction::Ret: { return true; } case Instruction::Store: { const StoreInst *store_inst = cast(inst); // The semantics of Store are: // Resolve the region D containing the data to be stored // Resolve the region P containing a pointer // Dereference P to get the region R that the data should be stored in // Transfer a unit of type type(D) from D to R const Value *value_operand = store_inst->getValueOperand(); const Value *pointer_operand = store_inst->getPointerOperand(); Type *pointer_ty = pointer_operand->getType(); PointerType *pointer_ptr_ty = dyn_cast(pointer_ty); if (!pointer_ptr_ty) return false; Type *target_ty = pointer_ptr_ty->getElementType(); lldb::addr_t D = frame.ResolveValue(value_operand, module); lldb::addr_t P = frame.ResolveValue(pointer_operand, module); if (D == LLDB_INVALID_ADDRESS) { LLDB_LOGF(log, "StoreInst's value doesn't resolve to anything"); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } if (P == LLDB_INVALID_ADDRESS) { LLDB_LOGF(log, "StoreInst's pointer doesn't resolve to anything"); error.SetErrorToGenericError(); error.SetErrorString(bad_value_error); return false; } lldb::addr_t R; lldb_private::Status read_error; execution_unit.ReadPointerFromMemory(&R, P, read_error); if (!read_error.Success()) { LLDB_LOGF(log, "Couldn't read the address to be loaded for a LoadInst"); error.SetErrorToGenericError(); error.SetErrorString(memory_read_error); return false; } size_t target_size = data_layout.getTypeStoreSize(target_ty); lldb_private::DataBufferHeap buffer(target_size, 0); read_error.Clear(); execution_unit.ReadMemory(buffer.GetBytes(), D, buffer.GetByteSize(), read_error); if (!read_error.Success()) { LLDB_LOGF(log, "Couldn't read from a region on behalf of a StoreInst"); error.SetErrorToGenericError(); error.SetErrorString(memory_read_error); return false; } lldb_private::Status write_error; execution_unit.WriteMemory(R, buffer.GetBytes(), buffer.GetByteSize(), write_error); if (!write_error.Success()) { LLDB_LOGF(log, "Couldn't write to a region on behalf of a StoreInst"); error.SetErrorToGenericError(); error.SetErrorString(memory_write_error); return false; } if (log) { LLDB_LOGF(log, "Interpreted a StoreInst"); LLDB_LOGF(log, " D : 0x%" PRIx64, D); LLDB_LOGF(log, " P : 0x%" PRIx64, P); LLDB_LOGF(log, " R : 0x%" PRIx64, R); } } break; case Instruction::Call: { const CallInst *call_inst = cast(inst); if (CanIgnoreCall(call_inst)) break; // Get the return type llvm::Type *returnType = call_inst->getType(); if (returnType == nullptr) { error.SetErrorToGenericError(); error.SetErrorString("unable to access return type"); return false; } // Work with void, integer and pointer return types if (!returnType->isVoidTy() && !returnType->isIntegerTy() && !returnType->isPointerTy()) { error.SetErrorToGenericError(); error.SetErrorString("return type is not supported"); return false; } // Check we can actually get a thread if (exe_ctx.GetThreadPtr() == nullptr) { error.SetErrorToGenericError(); error.SetErrorString("unable to acquire thread"); return false; } // Make sure we have a valid process if (!exe_ctx.GetProcessPtr()) { error.SetErrorToGenericError(); error.SetErrorString("unable to get the process"); return false; } // Find the address of the callee function lldb_private::Scalar I; const llvm::Value *val = call_inst->getCalledOperand(); if (!frame.EvaluateValue(I, val, module)) { error.SetErrorToGenericError(); error.SetErrorString("unable to get address of function"); return false; } lldb_private::Address funcAddr(I.ULongLong(LLDB_INVALID_ADDRESS)); lldb_private::DiagnosticManager diagnostics; lldb_private::EvaluateExpressionOptions options; // We generally receive a function pointer which we must dereference llvm::Type *prototype = val->getType(); if (!prototype->isPointerTy()) { error.SetErrorToGenericError(); error.SetErrorString("call need function pointer"); return false; } // Dereference the function pointer prototype = prototype->getPointerElementType(); if (!(prototype->isFunctionTy() || prototype->isFunctionVarArg())) { error.SetErrorToGenericError(); error.SetErrorString("call need function pointer"); return false; } // Find number of arguments const int numArgs = call_inst->getNumArgOperands(); // We work with a fixed array of 16 arguments which is our upper limit static lldb_private::ABI::CallArgument rawArgs[16]; if (numArgs >= 16) { error.SetErrorToGenericError(); error.SetErrorString("function takes too many arguments"); return false; } // Push all function arguments to the argument list that will be passed // to the call function thread plan for (int i = 0; i < numArgs; i++) { // Get details of this argument llvm::Value *arg_op = call_inst->getArgOperand(i); llvm::Type *arg_ty = arg_op->getType(); // Ensure that this argument is an supported type if (!arg_ty->isIntegerTy() && !arg_ty->isPointerTy()) { error.SetErrorToGenericError(); error.SetErrorStringWithFormat("argument %d must be integer type", i); return false; } // Extract the arguments value lldb_private::Scalar tmp_op = 0; if (!frame.EvaluateValue(tmp_op, arg_op, module)) { error.SetErrorToGenericError(); error.SetErrorStringWithFormat("unable to evaluate argument %d", i); return false; } // Check if this is a string literal or constant string pointer if (arg_ty->isPointerTy()) { lldb::addr_t addr = tmp_op.ULongLong(); size_t dataSize = 0; bool Success = execution_unit.GetAllocSize(addr, dataSize); (void)Success; assert(Success && "unable to locate host data for transfer to device"); // Create the required buffer rawArgs[i].size = dataSize; rawArgs[i].data_up.reset(new uint8_t[dataSize + 1]); // Read string from host memory execution_unit.ReadMemory(rawArgs[i].data_up.get(), addr, dataSize, error); assert(!error.Fail() && "we have failed to read the string from memory"); // Add null terminator rawArgs[i].data_up[dataSize] = '\0'; rawArgs[i].type = lldb_private::ABI::CallArgument::HostPointer; } else /* if ( arg_ty->isPointerTy() ) */ { rawArgs[i].type = lldb_private::ABI::CallArgument::TargetValue; // Get argument size in bytes rawArgs[i].size = arg_ty->getIntegerBitWidth() / 8; // Push value into argument list for thread plan rawArgs[i].value = tmp_op.ULongLong(); } } // Pack the arguments into an llvm::array llvm::ArrayRef args(rawArgs, numArgs); // Setup a thread plan to call the target function lldb::ThreadPlanSP call_plan_sp( new lldb_private::ThreadPlanCallFunctionUsingABI( exe_ctx.GetThreadRef(), funcAddr, *prototype, *returnType, args, options)); // Check if the plan is valid lldb_private::StreamString ss; if (!call_plan_sp || !call_plan_sp->ValidatePlan(&ss)) { error.SetErrorToGenericError(); error.SetErrorStringWithFormat( "unable to make ThreadPlanCallFunctionUsingABI for 0x%llx", I.ULongLong()); return false; } exe_ctx.GetProcessPtr()->SetRunningUserExpression(true); // Execute the actual function call thread plan lldb::ExpressionResults res = exe_ctx.GetProcessRef().RunThreadPlan( exe_ctx, call_plan_sp, options, diagnostics); // Check that the thread plan completed successfully if (res != lldb::ExpressionResults::eExpressionCompleted) { error.SetErrorToGenericError(); error.SetErrorString("ThreadPlanCallFunctionUsingABI failed"); return false; } exe_ctx.GetProcessPtr()->SetRunningUserExpression(false); // Void return type if (returnType->isVoidTy()) { // Cant assign to void types, so we leave the frame untouched } else // Integer or pointer return type if (returnType->isIntegerTy() || returnType->isPointerTy()) { // Get the encapsulated return value lldb::ValueObjectSP retVal = call_plan_sp.get()->GetReturnValueObject(); lldb_private::Scalar returnVal = -1; lldb_private::ValueObject *vobj = retVal.get(); // Check if the return value is valid if (vobj == nullptr || !retVal) { error.SetErrorToGenericError(); error.SetErrorString("unable to get the return value"); return false; } // Extract the return value as a integer lldb_private::Value &value = vobj->GetValue(); returnVal = value.GetScalar(); // Push the return value as the result frame.AssignValue(inst, returnVal, module); } } break; } ++frame.m_ii; } if (num_insts >= 4096) { error.SetErrorToGenericError(); error.SetErrorString(infinite_loop_error); return false; } return false; }