//===-- ABISysV_mips64.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 "ABISysV_mips64.h" #include "llvm/ADT/STLExtras.h" #include "llvm/TargetParser/Triple.h" #include "lldb/Core/Module.h" #include "lldb/Core/PluginManager.h" #include "lldb/Core/Value.h" #include "lldb/Core/ValueObjectConstResult.h" #include "lldb/Core/ValueObjectMemory.h" #include "lldb/Core/ValueObjectRegister.h" #include "lldb/Symbol/UnwindPlan.h" #include "lldb/Target/Process.h" #include "lldb/Target/RegisterContext.h" #include "lldb/Target/StackFrame.h" #include "lldb/Target/Target.h" #include "lldb/Target/Thread.h" #include "lldb/Utility/ConstString.h" #include "lldb/Utility/DataExtractor.h" #include "lldb/Utility/LLDBLog.h" #include "lldb/Utility/Log.h" #include "lldb/Utility/RegisterValue.h" #include "lldb/Utility/Status.h" #include using namespace lldb; using namespace lldb_private; LLDB_PLUGIN_DEFINE(ABISysV_mips64) enum dwarf_regnums { dwarf_r0 = 0, dwarf_r1, dwarf_r2, dwarf_r3, dwarf_r4, dwarf_r5, dwarf_r6, dwarf_r7, dwarf_r8, dwarf_r9, dwarf_r10, dwarf_r11, dwarf_r12, dwarf_r13, dwarf_r14, dwarf_r15, dwarf_r16, dwarf_r17, dwarf_r18, dwarf_r19, dwarf_r20, dwarf_r21, dwarf_r22, dwarf_r23, dwarf_r24, dwarf_r25, dwarf_r26, dwarf_r27, dwarf_r28, dwarf_r29, dwarf_r30, dwarf_r31, dwarf_sr, dwarf_lo, dwarf_hi, dwarf_bad, dwarf_cause, dwarf_pc }; static const RegisterInfo g_register_infos_mips64[] = { // NAME ALT SZ OFF ENCODING FORMAT EH_FRAME // DWARF GENERIC PROCESS PLUGIN // LLDB NATIVE // ======== ====== == === ============= ========== ============= // ================= ==================== ================= // ==================== {"r0", "zero", 8, 0, eEncodingUint, eFormatHex, {dwarf_r0, dwarf_r0, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r1", "AT", 8, 0, eEncodingUint, eFormatHex, {dwarf_r1, dwarf_r1, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r2", "v0", 8, 0, eEncodingUint, eFormatHex, {dwarf_r2, dwarf_r2, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r3", "v1", 8, 0, eEncodingUint, eFormatHex, {dwarf_r3, dwarf_r3, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r4", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r4, dwarf_r4, LLDB_REGNUM_GENERIC_ARG1, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r5", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r5, dwarf_r5, LLDB_REGNUM_GENERIC_ARG2, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r6", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r6, dwarf_r6, LLDB_REGNUM_GENERIC_ARG3, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r7", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r7, dwarf_r7, LLDB_REGNUM_GENERIC_ARG4, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r8", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r8, dwarf_r8, LLDB_REGNUM_GENERIC_ARG5, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r9", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r9, dwarf_r9, LLDB_REGNUM_GENERIC_ARG6, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r10", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r10, dwarf_r10, LLDB_REGNUM_GENERIC_ARG7, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r11", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r11, dwarf_r11, LLDB_REGNUM_GENERIC_ARG8, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r12", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r12, dwarf_r12, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r13", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r13, dwarf_r13, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r14", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r14, dwarf_r14, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r15", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r15, dwarf_r15, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r16", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r16, dwarf_r16, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r17", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r17, dwarf_r17, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r18", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r18, dwarf_r18, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r19", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r19, dwarf_r19, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r20", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r20, dwarf_r20, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r21", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r21, dwarf_r21, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r22", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r22, dwarf_r22, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r23", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r23, dwarf_r23, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r24", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r24, dwarf_r24, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r25", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r25, dwarf_r25, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r26", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r26, dwarf_r26, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r27", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r27, dwarf_r27, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r28", "gp", 8, 0, eEncodingUint, eFormatHex, {dwarf_r28, dwarf_r28, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r29", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r29, dwarf_r29, LLDB_REGNUM_GENERIC_SP, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r30", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r30, dwarf_r30, LLDB_REGNUM_GENERIC_FP, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"r31", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_r31, dwarf_r31, LLDB_REGNUM_GENERIC_RA, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"sr", nullptr, 4, 0, eEncodingUint, eFormatHex, {dwarf_sr, dwarf_sr, LLDB_REGNUM_GENERIC_FLAGS, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"lo", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_lo, dwarf_lo, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"hi", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_hi, dwarf_hi, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"bad", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_bad, dwarf_bad, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"cause", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_cause, dwarf_cause, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, {"pc", nullptr, 8, 0, eEncodingUint, eFormatHex, {dwarf_pc, dwarf_pc, LLDB_REGNUM_GENERIC_PC, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, nullptr, nullptr, nullptr, }, }; static const uint32_t k_num_register_infos = std::size(g_register_infos_mips64); const lldb_private::RegisterInfo * ABISysV_mips64::GetRegisterInfoArray(uint32_t &count) { count = k_num_register_infos; return g_register_infos_mips64; } size_t ABISysV_mips64::GetRedZoneSize() const { return 0; } // Static Functions ABISP ABISysV_mips64::CreateInstance(lldb::ProcessSP process_sp, const ArchSpec &arch) { if (arch.GetTriple().isMIPS64()) return ABISP( new ABISysV_mips64(std::move(process_sp), MakeMCRegisterInfo(arch))); return ABISP(); } bool ABISysV_mips64::PrepareTrivialCall(Thread &thread, addr_t sp, addr_t func_addr, addr_t return_addr, llvm::ArrayRef args) const { Log *log = GetLog(LLDBLog::Expressions); if (log) { StreamString s; s.Printf("ABISysV_mips64::PrepareTrivialCall (tid = 0x%" PRIx64 ", sp = 0x%" PRIx64 ", func_addr = 0x%" PRIx64 ", return_addr = 0x%" PRIx64, thread.GetID(), (uint64_t)sp, (uint64_t)func_addr, (uint64_t)return_addr); for (size_t i = 0; i < args.size(); ++i) s.Printf(", arg%zd = 0x%" PRIx64, i + 1, args[i]); s.PutCString(")"); log->PutString(s.GetString()); } RegisterContext *reg_ctx = thread.GetRegisterContext().get(); if (!reg_ctx) return false; const RegisterInfo *reg_info = nullptr; if (args.size() > 8) // TODO handle more than 8 arguments return false; for (size_t i = 0; i < args.size(); ++i) { reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1 + i); LLDB_LOGF(log, "About to write arg%zd (0x%" PRIx64 ") into %s", i + 1, args[i], reg_info->name); if (!reg_ctx->WriteRegisterFromUnsigned(reg_info, args[i])) return false; } // First, align the SP LLDB_LOGF(log, "16-byte aligning SP: 0x%" PRIx64 " to 0x%" PRIx64, (uint64_t)sp, (uint64_t)(sp & ~0xfull)); sp &= ~(0xfull); // 16-byte alignment Status error; const RegisterInfo *pc_reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC); const RegisterInfo *sp_reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP); const RegisterInfo *ra_reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_RA); const RegisterInfo *r25_info = reg_ctx->GetRegisterInfoByName("r25", 0); const RegisterInfo *r0_info = reg_ctx->GetRegisterInfoByName("zero", 0); LLDB_LOGF(log, "Writing R0: 0x%" PRIx64, (uint64_t)0); /* Write r0 with 0, in case we are stopped in syscall, * such setting prevents automatic decrement of the PC. * This clears the bug 23659 for MIPS. */ if (!reg_ctx->WriteRegisterFromUnsigned(r0_info, (uint64_t)0)) return false; LLDB_LOGF(log, "Writing SP: 0x%" PRIx64, (uint64_t)sp); // Set "sp" to the requested value if (!reg_ctx->WriteRegisterFromUnsigned(sp_reg_info, sp)) return false; LLDB_LOGF(log, "Writing RA: 0x%" PRIx64, (uint64_t)return_addr); // Set "ra" to the return address if (!reg_ctx->WriteRegisterFromUnsigned(ra_reg_info, return_addr)) return false; LLDB_LOGF(log, "Writing PC: 0x%" PRIx64, (uint64_t)func_addr); // Set pc to the address of the called function. if (!reg_ctx->WriteRegisterFromUnsigned(pc_reg_info, func_addr)) return false; LLDB_LOGF(log, "Writing r25: 0x%" PRIx64, (uint64_t)func_addr); // All callers of position independent functions must place the address of // the called function in t9 (r25) if (!reg_ctx->WriteRegisterFromUnsigned(r25_info, func_addr)) return false; return true; } bool ABISysV_mips64::GetArgumentValues(Thread &thread, ValueList &values) const { return false; } Status ABISysV_mips64::SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueObjectSP &new_value_sp) { Status error; if (!new_value_sp) { error.SetErrorString("Empty value object for return value."); return error; } CompilerType compiler_type = new_value_sp->GetCompilerType(); if (!compiler_type) { error.SetErrorString("Null clang type for return value."); return error; } Thread *thread = frame_sp->GetThread().get(); RegisterContext *reg_ctx = thread->GetRegisterContext().get(); if (!reg_ctx) error.SetErrorString("no registers are available"); DataExtractor data; Status data_error; size_t num_bytes = new_value_sp->GetData(data, data_error); if (data_error.Fail()) { error.SetErrorStringWithFormat( "Couldn't convert return value to raw data: %s", data_error.AsCString()); return error; } const uint32_t type_flags = compiler_type.GetTypeInfo(nullptr); if (type_flags & eTypeIsScalar || type_flags & eTypeIsPointer) { if (type_flags & eTypeIsInteger || type_flags & eTypeIsPointer) { lldb::offset_t offset = 0; if (num_bytes <= 16) { const RegisterInfo *r2_info = reg_ctx->GetRegisterInfoByName("r2", 0); if (num_bytes <= 8) { uint64_t raw_value = data.GetMaxU64(&offset, num_bytes); if (!reg_ctx->WriteRegisterFromUnsigned(r2_info, raw_value)) error.SetErrorString("failed to write register r2"); } else { uint64_t raw_value = data.GetMaxU64(&offset, 8); if (reg_ctx->WriteRegisterFromUnsigned(r2_info, raw_value)) { const RegisterInfo *r3_info = reg_ctx->GetRegisterInfoByName("r3", 0); raw_value = data.GetMaxU64(&offset, num_bytes - offset); if (!reg_ctx->WriteRegisterFromUnsigned(r3_info, raw_value)) error.SetErrorString("failed to write register r3"); } else error.SetErrorString("failed to write register r2"); } } else { error.SetErrorString("We don't support returning longer than 128 bit " "integer values at present."); } } else if (type_flags & eTypeIsFloat) { error.SetErrorString("TODO: Handle Float Types."); } } else if (type_flags & eTypeIsVector) { error.SetErrorString("returning vector values are not supported"); } return error; } ValueObjectSP ABISysV_mips64::GetReturnValueObjectSimple( Thread &thread, CompilerType &return_compiler_type) const { ValueObjectSP return_valobj_sp; return return_valobj_sp; } ValueObjectSP ABISysV_mips64::GetReturnValueObjectImpl( Thread &thread, CompilerType &return_compiler_type) const { ValueObjectSP return_valobj_sp; Value value; Status error; ExecutionContext exe_ctx(thread.shared_from_this()); if (exe_ctx.GetTargetPtr() == nullptr || exe_ctx.GetProcessPtr() == nullptr) return return_valobj_sp; value.SetCompilerType(return_compiler_type); RegisterContext *reg_ctx = thread.GetRegisterContext().get(); if (!reg_ctx) return return_valobj_sp; Target *target = exe_ctx.GetTargetPtr(); const ArchSpec target_arch = target->GetArchitecture(); ByteOrder target_byte_order = target_arch.GetByteOrder(); std::optional byte_size = return_compiler_type.GetByteSize(&thread); if (!byte_size) return return_valobj_sp; const uint32_t type_flags = return_compiler_type.GetTypeInfo(nullptr); uint32_t fp_flag = target_arch.GetFlags() & lldb_private::ArchSpec::eMIPS_ABI_FP_mask; const RegisterInfo *r2_info = reg_ctx->GetRegisterInfoByName("r2", 0); const RegisterInfo *r3_info = reg_ctx->GetRegisterInfoByName("r3", 0); assert(r2_info && r3_info && "Basic registers should always be present."); if (type_flags & eTypeIsScalar || type_flags & eTypeIsPointer) { value.SetValueType(Value::ValueType::Scalar); bool success = false; if (type_flags & eTypeIsInteger || type_flags & eTypeIsPointer) { // Extract the register context so we can read arguments from registers // In MIPS register "r2" (v0) holds the integer function return values uint64_t raw_value = reg_ctx->ReadRegisterAsUnsigned(r2_info, 0); const bool is_signed = (type_flags & eTypeIsSigned) != 0; switch (*byte_size) { default: break; case sizeof(uint64_t): if (is_signed) value.GetScalar() = (int64_t)(raw_value); else value.GetScalar() = (uint64_t)(raw_value); success = true; break; case sizeof(uint32_t): if (is_signed) value.GetScalar() = (int32_t)(raw_value & UINT32_MAX); else value.GetScalar() = (uint32_t)(raw_value & UINT32_MAX); success = true; break; case sizeof(uint16_t): if (is_signed) value.GetScalar() = (int16_t)(raw_value & UINT16_MAX); else value.GetScalar() = (uint16_t)(raw_value & UINT16_MAX); success = true; break; case sizeof(uint8_t): if (is_signed) value.GetScalar() = (int8_t)(raw_value & UINT8_MAX); else value.GetScalar() = (uint8_t)(raw_value & UINT8_MAX); success = true; break; } } else if (type_flags & eTypeIsFloat) { if (type_flags & eTypeIsComplex) { // Don't handle complex yet. } else if (IsSoftFloat(fp_flag)) { uint64_t raw_value = reg_ctx->ReadRegisterAsUnsigned(r2_info, 0); switch (*byte_size) { case 4: value.GetScalar() = *((float *)(&raw_value)); success = true; break; case 8: value.GetScalar() = *((double *)(&raw_value)); success = true; break; case 16: uint64_t result[2]; if (target_byte_order == eByteOrderLittle) { result[0] = raw_value; result[1] = reg_ctx->ReadRegisterAsUnsigned(r3_info, 0); value.GetScalar() = *((long double *)(result)); } else { result[0] = reg_ctx->ReadRegisterAsUnsigned(r3_info, 0); result[1] = raw_value; value.GetScalar() = *((long double *)(result)); } success = true; break; } } else { if (*byte_size <= sizeof(long double)) { const RegisterInfo *f0_info = reg_ctx->GetRegisterInfoByName("f0", 0); RegisterValue f0_value; DataExtractor f0_data; reg_ctx->ReadRegister(f0_info, f0_value); f0_value.GetData(f0_data); lldb::offset_t offset = 0; if (*byte_size == sizeof(float)) { value.GetScalar() = (float)f0_data.GetFloat(&offset); success = true; } else if (*byte_size == sizeof(double)) { value.GetScalar() = (double)f0_data.GetDouble(&offset); success = true; } else if (*byte_size == sizeof(long double)) { const RegisterInfo *f2_info = reg_ctx->GetRegisterInfoByName("f2", 0); RegisterValue f2_value; DataExtractor f2_data; reg_ctx->ReadRegister(f2_info, f2_value); DataExtractor *copy_from_extractor = nullptr; WritableDataBufferSP data_sp(new DataBufferHeap(16, 0)); DataExtractor return_ext( data_sp, target_byte_order, target->GetArchitecture().GetAddressByteSize()); if (target_byte_order == eByteOrderLittle) { copy_from_extractor = &f0_data; copy_from_extractor->CopyByteOrderedData( 0, 8, data_sp->GetBytes(), *byte_size - 8, target_byte_order); f2_value.GetData(f2_data); copy_from_extractor = &f2_data; copy_from_extractor->CopyByteOrderedData( 0, 8, data_sp->GetBytes() + 8, *byte_size - 8, target_byte_order); } else { copy_from_extractor = &f0_data; copy_from_extractor->CopyByteOrderedData( 0, 8, data_sp->GetBytes() + 8, *byte_size - 8, target_byte_order); f2_value.GetData(f2_data); copy_from_extractor = &f2_data; copy_from_extractor->CopyByteOrderedData( 0, 8, data_sp->GetBytes(), *byte_size - 8, target_byte_order); } return_valobj_sp = ValueObjectConstResult::Create( &thread, return_compiler_type, ConstString(""), return_ext); return return_valobj_sp; } } } } if (success) return_valobj_sp = ValueObjectConstResult::Create( thread.GetStackFrameAtIndex(0).get(), value, ConstString("")); } else if (type_flags & eTypeIsStructUnion || type_flags & eTypeIsClass || type_flags & eTypeIsVector) { // Any structure of up to 16 bytes in size is returned in the registers. if (*byte_size <= 16) { WritableDataBufferSP data_sp(new DataBufferHeap(16, 0)); DataExtractor return_ext(data_sp, target_byte_order, target->GetArchitecture().GetAddressByteSize()); RegisterValue r2_value, r3_value, f0_value, f1_value, f2_value; // Tracks how much bytes of r2 and r3 registers we've consumed so far uint32_t integer_bytes = 0; // True if return values are in FP return registers. bool use_fp_regs = false; // True if we found any non floating point field in structure. bool found_non_fp_field = false; // True if return values are in r2 register. bool use_r2 = false; // True if return values are in r3 register. bool use_r3 = false; // True if the result is copied into our data buffer bool sucess = false; std::string name; bool is_complex; uint32_t count; const uint32_t num_children = return_compiler_type.GetNumFields(); // A structure consisting of one or two FP values (and nothing else) will // be returned in the two FP return-value registers i.e fp0 and fp2. if (num_children <= 2) { uint64_t field_bit_offset = 0; // Check if this structure contains only floating point fields for (uint32_t idx = 0; idx < num_children; idx++) { CompilerType field_compiler_type = return_compiler_type.GetFieldAtIndex(idx, name, &field_bit_offset, nullptr, nullptr); if (field_compiler_type.IsFloatingPointType(count, is_complex)) use_fp_regs = true; else found_non_fp_field = true; } if (use_fp_regs && !found_non_fp_field) { // We have one or two FP-only values in this structure. Get it from // f0/f2 registers. DataExtractor f0_data, f1_data, f2_data; const RegisterInfo *f0_info = reg_ctx->GetRegisterInfoByName("f0", 0); const RegisterInfo *f1_info = reg_ctx->GetRegisterInfoByName("f1", 0); const RegisterInfo *f2_info = reg_ctx->GetRegisterInfoByName("f2", 0); reg_ctx->ReadRegister(f0_info, f0_value); reg_ctx->ReadRegister(f2_info, f2_value); f0_value.GetData(f0_data); for (uint32_t idx = 0; idx < num_children; idx++) { CompilerType field_compiler_type = return_compiler_type.GetFieldAtIndex( idx, name, &field_bit_offset, nullptr, nullptr); std::optional field_byte_width = field_compiler_type.GetByteSize(&thread); if (!field_byte_width) return return_valobj_sp; DataExtractor *copy_from_extractor = nullptr; uint64_t return_value[2]; offset_t offset = 0; if (idx == 0) { // This case is for long double type. if (*field_byte_width == 16) { // If structure contains long double type, then it is returned // in fp0/fp1 registers. if (target_byte_order == eByteOrderLittle) { return_value[0] = f0_data.GetU64(&offset); reg_ctx->ReadRegister(f1_info, f1_value); f1_value.GetData(f1_data); offset = 0; return_value[1] = f1_data.GetU64(&offset); } else { return_value[1] = f0_data.GetU64(&offset); reg_ctx->ReadRegister(f1_info, f1_value); f1_value.GetData(f1_data); offset = 0; return_value[0] = f1_data.GetU64(&offset); } f0_data.SetData(return_value, *field_byte_width, target_byte_order); } copy_from_extractor = &f0_data; // This is in f0, copy from // register to our result // structure } else { f2_value.GetData(f2_data); // This is in f2, copy from register to our result structure copy_from_extractor = &f2_data; } // Sanity check to avoid crash if (!copy_from_extractor || *field_byte_width > copy_from_extractor->GetByteSize()) return return_valobj_sp; // copy the register contents into our data buffer copy_from_extractor->CopyByteOrderedData( 0, *field_byte_width, data_sp->GetBytes() + (field_bit_offset / 8), *field_byte_width, target_byte_order); } // The result is in our data buffer. Create a variable object out of // it return_valobj_sp = ValueObjectConstResult::Create( &thread, return_compiler_type, ConstString(""), return_ext); return return_valobj_sp; } } // If we reach here, it means this structure either contains more than // two fields or it contains at least one non floating point type. In // that case, all fields are returned in GP return registers. for (uint32_t idx = 0; idx < num_children; idx++) { uint64_t field_bit_offset = 0; bool is_signed; uint32_t padding; CompilerType field_compiler_type = return_compiler_type.GetFieldAtIndex( idx, name, &field_bit_offset, nullptr, nullptr); std::optional field_byte_width = field_compiler_type.GetByteSize(&thread); // if we don't know the size of the field (e.g. invalid type), just // bail out if (!field_byte_width || *field_byte_width == 0) break; uint32_t field_byte_offset = field_bit_offset / 8; if (field_compiler_type.IsIntegerOrEnumerationType(is_signed) || field_compiler_type.IsPointerType() || field_compiler_type.IsFloatingPointType(count, is_complex)) { padding = field_byte_offset - integer_bytes; if (integer_bytes < 8) { // We have not yet consumed r2 completely. if (integer_bytes + *field_byte_width + padding <= 8) { // This field fits in r2, copy its value from r2 to our result // structure integer_bytes = integer_bytes + *field_byte_width + padding; // Increase the consumed bytes. use_r2 = true; } else { // There isn't enough space left in r2 for this field, so this // will be in r3. integer_bytes = integer_bytes + *field_byte_width + padding; // Increase the consumed bytes. use_r3 = true; } } // We already have consumed at-least 8 bytes that means r2 is done, // and this field will be in r3. Check if this field can fit in r3. else if (integer_bytes + *field_byte_width + padding <= 16) { integer_bytes = integer_bytes + *field_byte_width + padding; use_r3 = true; } else { // There isn't any space left for this field, this should not // happen as we have already checked the overall size is not // greater than 16 bytes. For now, return a nullptr return value // object. return return_valobj_sp; } } } // Vector types up to 16 bytes are returned in GP return registers if (type_flags & eTypeIsVector) { if (*byte_size <= 8) use_r2 = true; else { use_r2 = true; use_r3 = true; } } if (use_r2) { reg_ctx->ReadRegister(r2_info, r2_value); const size_t bytes_copied = r2_value.GetAsMemoryData( *r2_info, data_sp->GetBytes(), r2_info->byte_size, target_byte_order, error); if (bytes_copied != r2_info->byte_size) return return_valobj_sp; sucess = true; } if (use_r3) { reg_ctx->ReadRegister(r3_info, r3_value); const size_t bytes_copied = r3_value.GetAsMemoryData( *r3_info, data_sp->GetBytes() + r2_info->byte_size, r3_info->byte_size, target_byte_order, error); if (bytes_copied != r3_info->byte_size) return return_valobj_sp; sucess = true; } if (sucess) { // The result is in our data buffer. Create a variable object out of // it return_valobj_sp = ValueObjectConstResult::Create( &thread, return_compiler_type, ConstString(""), return_ext); } return return_valobj_sp; } // Any structure/vector greater than 16 bytes in size is returned in // memory. The pointer to that memory is returned in r2. uint64_t mem_address = reg_ctx->ReadRegisterAsUnsigned( reg_ctx->GetRegisterInfoByName("r2", 0), 0); // We have got the address. Create a memory object out of it return_valobj_sp = ValueObjectMemory::Create( &thread, "", Address(mem_address, nullptr), return_compiler_type); } return return_valobj_sp; } bool ABISysV_mips64::CreateFunctionEntryUnwindPlan(UnwindPlan &unwind_plan) { unwind_plan.Clear(); unwind_plan.SetRegisterKind(eRegisterKindDWARF); UnwindPlan::RowSP row(new UnwindPlan::Row); // Our Call Frame Address is the stack pointer value row->GetCFAValue().SetIsRegisterPlusOffset(dwarf_r29, 0); // The previous PC is in the RA row->SetRegisterLocationToRegister(dwarf_pc, dwarf_r31, true); unwind_plan.AppendRow(row); // All other registers are the same. unwind_plan.SetSourceName("mips64 at-func-entry default"); unwind_plan.SetSourcedFromCompiler(eLazyBoolNo); unwind_plan.SetReturnAddressRegister(dwarf_r31); return true; } bool ABISysV_mips64::CreateDefaultUnwindPlan(UnwindPlan &unwind_plan) { unwind_plan.Clear(); unwind_plan.SetRegisterKind(eRegisterKindDWARF); UnwindPlan::RowSP row(new UnwindPlan::Row); row->SetUnspecifiedRegistersAreUndefined(true); row->GetCFAValue().SetIsRegisterPlusOffset(dwarf_r29, 0); row->SetRegisterLocationToRegister(dwarf_pc, dwarf_r31, true); unwind_plan.AppendRow(row); unwind_plan.SetSourceName("mips64 default unwind plan"); unwind_plan.SetSourcedFromCompiler(eLazyBoolNo); unwind_plan.SetUnwindPlanValidAtAllInstructions(eLazyBoolNo); unwind_plan.SetUnwindPlanForSignalTrap(eLazyBoolNo); return true; } bool ABISysV_mips64::RegisterIsVolatile(const RegisterInfo *reg_info) { return !RegisterIsCalleeSaved(reg_info); } bool ABISysV_mips64::IsSoftFloat(uint32_t fp_flag) const { return (fp_flag == lldb_private::ArchSpec::eMIPS_ABI_FP_SOFT); } bool ABISysV_mips64::RegisterIsCalleeSaved(const RegisterInfo *reg_info) { if (reg_info) { // Preserved registers are : // r16-r23, r28, r29, r30, r31 int reg = ((reg_info->byte_offset) / 8); bool save = (reg >= 16) && (reg <= 23); save |= (reg >= 28) && (reg <= 31); return save; } return false; } void ABISysV_mips64::Initialize() { PluginManager::RegisterPlugin( GetPluginNameStatic(), "System V ABI for mips64 targets", CreateInstance); } void ABISysV_mips64::Terminate() { PluginManager::UnregisterPlugin(CreateInstance); }