//===-- ABISysV_arc.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_arc.h"
// C Includes
// C++ Includes
#include <array>
#include <limits>
#include <type_traits>
// Other libraries and framework includes
#include "llvm/IR/DerivedTypes.h"
#include "llvm/Support/MathExtras.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/RegisterValue.h"
#include "lldb/Utility/Status.h"
#define DEFINE_REG_NAME(reg_num) ConstString(#reg_num).GetCString()
#define DEFINE_REG_NAME_STR(reg_name) ConstString(reg_name).GetCString()
// The ABI is not a source of such information as size, offset, encoding, etc.
// of a register. Just provides correct dwarf and eh_frame numbers.
#define DEFINE_GENERIC_REGISTER_STUB(dwarf_num, str_name, generic_num) \
{ \
DEFINE_REG_NAME(dwarf_num), DEFINE_REG_NAME_STR(str_name), \
0, 0, eEncodingInvalid, eFormatDefault, \
{ dwarf_num, dwarf_num, generic_num, LLDB_INVALID_REGNUM, dwarf_num }, \
nullptr, nullptr, nullptr, \
}
#define DEFINE_REGISTER_STUB(dwarf_num, str_name) \
DEFINE_GENERIC_REGISTER_STUB(dwarf_num, str_name, LLDB_INVALID_REGNUM)
using namespace lldb;
using namespace lldb_private;
LLDB_PLUGIN_DEFINE_ADV(ABISysV_arc, ABIARC)
namespace {
namespace dwarf {
enum regnums {
r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15, r16,
r17, r18, r19, r20, r21, r22, r23, r24, r25, r26,
r27, fp = r27, r28, sp = r28, r29, r30, r31, blink = r31,
r32, r33, r34, r35, r36, r37, r38, r39, r40, r41, r42, r43, r44, r45, r46,
r47, r48, r49, r50, r51, r52, r53, r54, r55, r56, r57, r58, r59, r60,
/*reserved,*/ /*limm indicator,*/ r63 = 63, pc = 70, status32 = 74
};
static const std::array<RegisterInfo, 64> g_register_infos = { {
DEFINE_GENERIC_REGISTER_STUB(r0, nullptr, LLDB_REGNUM_GENERIC_ARG1),
DEFINE_GENERIC_REGISTER_STUB(r1, nullptr, LLDB_REGNUM_GENERIC_ARG2),
DEFINE_GENERIC_REGISTER_STUB(r2, nullptr, LLDB_REGNUM_GENERIC_ARG3),
DEFINE_GENERIC_REGISTER_STUB(r3, nullptr, LLDB_REGNUM_GENERIC_ARG4),
DEFINE_GENERIC_REGISTER_STUB(r4, nullptr, LLDB_REGNUM_GENERIC_ARG5),
DEFINE_GENERIC_REGISTER_STUB(r5, nullptr, LLDB_REGNUM_GENERIC_ARG6),
DEFINE_GENERIC_REGISTER_STUB(r6, nullptr, LLDB_REGNUM_GENERIC_ARG7),
DEFINE_GENERIC_REGISTER_STUB(r7, nullptr, LLDB_REGNUM_GENERIC_ARG8),
DEFINE_REGISTER_STUB(r8, nullptr),
DEFINE_REGISTER_STUB(r9, nullptr),
DEFINE_REGISTER_STUB(r10, nullptr),
DEFINE_REGISTER_STUB(r11, nullptr),
DEFINE_REGISTER_STUB(r12, nullptr),
DEFINE_REGISTER_STUB(r13, nullptr),
DEFINE_REGISTER_STUB(r14, nullptr),
DEFINE_REGISTER_STUB(r15, nullptr),
DEFINE_REGISTER_STUB(r16, nullptr),
DEFINE_REGISTER_STUB(r17, nullptr),
DEFINE_REGISTER_STUB(r18, nullptr),
DEFINE_REGISTER_STUB(r19, nullptr),
DEFINE_REGISTER_STUB(r20, nullptr),
DEFINE_REGISTER_STUB(r21, nullptr),
DEFINE_REGISTER_STUB(r22, nullptr),
DEFINE_REGISTER_STUB(r23, nullptr),
DEFINE_REGISTER_STUB(r24, nullptr),
DEFINE_REGISTER_STUB(r25, nullptr),
DEFINE_REGISTER_STUB(r26, "gp"),
DEFINE_GENERIC_REGISTER_STUB(r27, "fp", LLDB_REGNUM_GENERIC_FP),
DEFINE_GENERIC_REGISTER_STUB(r28, "sp", LLDB_REGNUM_GENERIC_SP),
DEFINE_REGISTER_STUB(r29, "ilink"),
DEFINE_REGISTER_STUB(r30, nullptr),
DEFINE_GENERIC_REGISTER_STUB(r31, "blink", LLDB_REGNUM_GENERIC_RA),
DEFINE_REGISTER_STUB(r32, nullptr),
DEFINE_REGISTER_STUB(r33, nullptr),
DEFINE_REGISTER_STUB(r34, nullptr),
DEFINE_REGISTER_STUB(r35, nullptr),
DEFINE_REGISTER_STUB(r36, nullptr),
DEFINE_REGISTER_STUB(r37, nullptr),
DEFINE_REGISTER_STUB(r38, nullptr),
DEFINE_REGISTER_STUB(r39, nullptr),
DEFINE_REGISTER_STUB(r40, nullptr),
DEFINE_REGISTER_STUB(r41, nullptr),
DEFINE_REGISTER_STUB(r42, nullptr),
DEFINE_REGISTER_STUB(r43, nullptr),
DEFINE_REGISTER_STUB(r44, nullptr),
DEFINE_REGISTER_STUB(r45, nullptr),
DEFINE_REGISTER_STUB(r46, nullptr),
DEFINE_REGISTER_STUB(r47, nullptr),
DEFINE_REGISTER_STUB(r48, nullptr),
DEFINE_REGISTER_STUB(r49, nullptr),
DEFINE_REGISTER_STUB(r50, nullptr),
DEFINE_REGISTER_STUB(r51, nullptr),
DEFINE_REGISTER_STUB(r52, nullptr),
DEFINE_REGISTER_STUB(r53, nullptr),
DEFINE_REGISTER_STUB(r54, nullptr),
DEFINE_REGISTER_STUB(r55, nullptr),
DEFINE_REGISTER_STUB(r56, nullptr),
DEFINE_REGISTER_STUB(r57, nullptr),
DEFINE_REGISTER_STUB(r58, "accl"),
DEFINE_REGISTER_STUB(r59, "acch"),
DEFINE_REGISTER_STUB(r60, "lp_count"),
DEFINE_REGISTER_STUB(r63, "pcl"),
DEFINE_GENERIC_REGISTER_STUB(pc, nullptr, LLDB_REGNUM_GENERIC_PC),
DEFINE_GENERIC_REGISTER_STUB(status32, nullptr, LLDB_REGNUM_GENERIC_FLAGS)} };
} // namespace dwarf
} // namespace
const RegisterInfo *ABISysV_arc::GetRegisterInfoArray(uint32_t &count) {
count = dwarf::g_register_infos.size();
return dwarf::g_register_infos.data();
}
size_t ABISysV_arc::GetRedZoneSize() const { return 0; }
bool ABISysV_arc::IsRegisterFileReduced(RegisterContext ®_ctx) const {
if (!m_is_reg_file_reduced) {
const auto *const rf_build_reg = reg_ctx.GetRegisterInfoByName("rf_build");
const auto reg_value = reg_ctx.ReadRegisterAsUnsigned(rf_build_reg,
/*fail_value*/ 0);
// RF_BUILD "Number of Entries" bit.
const uint32_t rf_entries_bit = 1U << 9U;
m_is_reg_file_reduced = (reg_value & rf_entries_bit) != 0;
}
return m_is_reg_file_reduced.value_or(false);
}
//------------------------------------------------------------------
// Static Functions
//------------------------------------------------------------------
ABISP ABISysV_arc::CreateInstance(ProcessSP process_sp, const ArchSpec &arch) {
return llvm::Triple::arc == arch.GetTriple().getArch() ?
ABISP(new ABISysV_arc(std::move(process_sp), MakeMCRegisterInfo(arch))) :
ABISP();
}
static const size_t word_size = 4U;
static const size_t reg_size = word_size;
static inline size_t AugmentArgSize(size_t size_in_bytes) {
return llvm::alignTo(size_in_bytes, word_size);
}
static size_t
TotalArgsSizeInWords(const llvm::ArrayRef<ABI::CallArgument> &args) {
size_t total_size = 0;
for (const auto &arg : args)
total_size +=
(ABI::CallArgument::TargetValue == arg.type ? AugmentArgSize(arg.size)
: reg_size) /
word_size;
return total_size;
}
bool ABISysV_arc::PrepareTrivialCall(Thread &thread, addr_t sp,
addr_t func_addr, addr_t return_addr,
llvm::ArrayRef<addr_t> args) const {
// We don't use the traditional trivial call specialized for jit.
return false;
}
bool ABISysV_arc::PrepareTrivialCall(Thread &thread, addr_t sp, addr_t pc,
addr_t ra, llvm::Type &prototype,
llvm::ArrayRef<ABI::CallArgument> args) const {
auto reg_ctx = thread.GetRegisterContext();
if (!reg_ctx)
return false;
uint32_t pc_reg = reg_ctx->ConvertRegisterKindToRegisterNumber(
eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC);
if (pc_reg == LLDB_INVALID_REGNUM)
return false;
uint32_t ra_reg = reg_ctx->ConvertRegisterKindToRegisterNumber(
eRegisterKindGeneric, LLDB_REGNUM_GENERIC_RA);
if (ra_reg == LLDB_INVALID_REGNUM)
return false;
uint32_t sp_reg = reg_ctx->ConvertRegisterKindToRegisterNumber(
eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP);
if (sp_reg == LLDB_INVALID_REGNUM)
return false;
Status error;
ProcessSP process = thread.GetProcess();
if (!process)
return false;
// Push host data onto target.
for (const auto &arg : args) {
// Skip over target values.
if (arg.type == ABI::CallArgument::TargetValue)
continue;
// Create space on the stack for this data 4-byte aligned.
sp -= AugmentArgSize(arg.size);
if (process->WriteMemory(sp, arg.data_up.get(), arg.size, error) < arg.size
|| error.Fail())
return false;
// Update the argument with the target pointer.
*const_cast<addr_t *>(&arg.value) = sp;
}
// Make sure number of parameters matches prototype.
assert(!prototype.isFunctionVarArg());
assert(prototype.getFunctionNumParams() == args.size());
const size_t regs_for_args_count = IsRegisterFileReduced(*reg_ctx) ? 4U : 8U;
// Number of arguments passed on stack.
auto args_size = TotalArgsSizeInWords(args);
auto on_stack =
args_size <= regs_for_args_count ? 0 : args_size - regs_for_args_count;
auto offset = on_stack * word_size;
uint8_t reg_value[reg_size];
size_t reg_index = LLDB_REGNUM_GENERIC_ARG1;
for (const auto &arg : args) {
auto value = reinterpret_cast<const uint8_t *>(&arg.value);
auto size =
ABI::CallArgument::TargetValue == arg.type ? arg.size : reg_size;
// Pass arguments via registers.
while (size > 0 && reg_index < regs_for_args_count) {
size_t byte_index = 0;
auto end = size < reg_size ? size : reg_size;
while (byte_index < end) {
reg_value[byte_index++] = *(value++);
--size;
}
while (byte_index < reg_size) {
reg_value[byte_index++] = 0;
}
RegisterValue reg_val_obj(llvm::ArrayRef(reg_value, reg_size),
eByteOrderLittle);
if (!reg_ctx->WriteRegister(
reg_ctx->GetRegisterInfo(eRegisterKindGeneric, reg_index),
reg_val_obj))
return false;
// NOTE: It's unsafe to iterate through LLDB_REGNUM_GENERICs.
++reg_index;
}
if (reg_index < regs_for_args_count || size == 0)
continue;
// Remaining arguments are passed on the stack.
if (process->WriteMemory(sp - offset, value, size, error) < size ||
!error.Success())
return false;
offset -= AugmentArgSize(size);
}
// Set stack pointer immediately below arguments.
sp -= on_stack * word_size;
// Update registers with current function call state.
reg_ctx->WriteRegisterFromUnsigned(pc_reg, pc);
reg_ctx->WriteRegisterFromUnsigned(ra_reg, ra);
reg_ctx->WriteRegisterFromUnsigned(sp_reg, sp);
return true;
}
bool ABISysV_arc::GetArgumentValues(Thread &thread, ValueList &values) const {
return false;
}
Status ABISysV_arc::SetReturnValueObject(StackFrameSP &frame_sp,
ValueObjectSP &new_value_sp) {
Status result;
if (!new_value_sp) {
result = Status::FromErrorString("Empty value object for return value.");
return result;
}
CompilerType compiler_type = new_value_sp->GetCompilerType();
if (!compiler_type) {
result = Status::FromErrorString("Null clang type for return value.");
return result;
}
auto ®_ctx = *frame_sp->GetThread()->GetRegisterContext();
bool is_signed = false;
if (!compiler_type.IsIntegerOrEnumerationType(is_signed) &&
!compiler_type.IsPointerType()) {
result = Status::FromErrorString(
"We don't support returning other types at present");
return result;
}
DataExtractor data;
size_t num_bytes = new_value_sp->GetData(data, result);
if (result.Fail()) {
result = Status::FromErrorStringWithFormat(
"Couldn't convert return value to raw data: %s", result.AsCString());
return result;
}
if (num_bytes <= 2 * reg_size) {
offset_t offset = 0;
uint64_t raw_value = data.GetMaxU64(&offset, num_bytes);
auto reg_info =
reg_ctx.GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1);
if (!reg_ctx.WriteRegisterFromUnsigned(reg_info, raw_value)) {
result = Status::FromErrorStringWithFormat(
"Couldn't write value to register %s", reg_info->name);
return result;
}
if (num_bytes <= reg_size)
return result; // Successfully written.
raw_value >>= 32;
reg_info =
reg_ctx.GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG2);
if (!reg_ctx.WriteRegisterFromUnsigned(reg_info, raw_value)) {
result = Status::FromErrorStringWithFormat(
"Couldn't write value to register %s", reg_info->name);
}
return result;
}
result = Status::FromErrorString(
"We don't support returning large integer values at present.");
return result;
}
template <typename T>
static void SetInteger(Scalar &scalar, uint64_t raw_value, bool is_signed) {
raw_value &= std::numeric_limits<T>::max();
if (is_signed)
scalar = static_cast<typename std::make_signed<T>::type>(raw_value);
else
scalar = static_cast<T>(raw_value);
}
static bool SetSizedInteger(Scalar &scalar, uint64_t raw_value,
uint8_t size_in_bytes, bool is_signed) {
switch (size_in_bytes) {
default:
return false;
case sizeof(uint64_t):
SetInteger<uint64_t>(scalar, raw_value, is_signed);
break;
case sizeof(uint32_t):
SetInteger<uint32_t>(scalar, raw_value, is_signed);
break;
case sizeof(uint16_t):
SetInteger<uint16_t>(scalar, raw_value, is_signed);
break;
case sizeof(uint8_t):
SetInteger<uint8_t>(scalar, raw_value, is_signed);
break;
}
return true;
}
static bool SetSizedFloat(Scalar &scalar, uint64_t raw_value,
uint8_t size_in_bytes) {
switch (size_in_bytes) {
default:
return false;
case sizeof(uint64_t):
scalar = *reinterpret_cast<double *>(&raw_value);
break;
case sizeof(uint32_t):
scalar = *reinterpret_cast<float *>(&raw_value);
break;
}
return true;
}
static uint64_t ReadRawValue(const RegisterContextSP ®_ctx,
uint8_t size_in_bytes) {
auto reg_info_r0 =
reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1);
// Extract the register context so we can read arguments from registers.
uint64_t raw_value =
reg_ctx->ReadRegisterAsUnsigned(reg_info_r0, 0) & UINT32_MAX;
if (sizeof(uint64_t) == size_in_bytes)
raw_value |= (reg_ctx->ReadRegisterAsUnsigned(
reg_ctx->GetRegisterInfo(eRegisterKindGeneric,
LLDB_REGNUM_GENERIC_ARG2), 0) &
UINT64_MAX) << 32U;
return raw_value;
}
ValueObjectSP
ABISysV_arc::GetReturnValueObjectSimple(Thread &thread,
CompilerType &compiler_type) const {
if (!compiler_type)
return ValueObjectSP();
auto reg_ctx = thread.GetRegisterContext();
if (!reg_ctx)
return ValueObjectSP();
Value value;
value.SetCompilerType(compiler_type);
const uint32_t type_flags = compiler_type.GetTypeInfo();
// Integer return type.
if (type_flags & eTypeIsInteger) {
const size_t byte_size = compiler_type.GetByteSize(&thread).value_or(0);
auto raw_value = ReadRawValue(reg_ctx, byte_size);
const bool is_signed = (type_flags & eTypeIsSigned) != 0;
if (!SetSizedInteger(value.GetScalar(), raw_value, byte_size, is_signed))
return ValueObjectSP();
value.SetValueType(Value::ValueType::Scalar);
}
// Pointer return type.
else if (type_flags & eTypeIsPointer) {
auto reg_info_r0 = reg_ctx->GetRegisterInfo(eRegisterKindGeneric,
LLDB_REGNUM_GENERIC_ARG1);
value.GetScalar() = reg_ctx->ReadRegisterAsUnsigned(reg_info_r0, 0);
value.SetValueType(Value::ValueType::Scalar);
}
// Floating point return type.
else if (type_flags & eTypeIsFloat) {
uint32_t float_count = 0;
bool is_complex = false;
if (compiler_type.IsFloatingPointType(float_count, is_complex) &&
1 == float_count && !is_complex) {
const size_t byte_size = compiler_type.GetByteSize(&thread).value_or(0);
auto raw_value = ReadRawValue(reg_ctx, byte_size);
if (!SetSizedFloat(value.GetScalar(), raw_value, byte_size))
return ValueObjectSP();
}
}
// Unsupported return type.
else
return ValueObjectSP();
return ValueObjectConstResult::Create(thread.GetStackFrameAtIndex(0).get(),
value, ConstString(""));
}
ValueObjectSP ABISysV_arc::GetReturnValueObjectImpl(
Thread &thread, CompilerType &return_compiler_type) const {
ValueObjectSP return_valobj_sp;
if (!return_compiler_type)
return return_valobj_sp;
ExecutionContext exe_ctx(thread.shared_from_this());
return GetReturnValueObjectSimple(thread, return_compiler_type);
}
ValueObjectSP ABISysV_arc::GetReturnValueObjectImpl(Thread &thread,
llvm::Type &retType) const {
auto reg_ctx = thread.GetRegisterContext();
if (!reg_ctx)
return ValueObjectSP();
Value value;
// Void return type.
if (retType.isVoidTy()) {
value.GetScalar() = 0;
}
// Integer return type.
else if (retType.isIntegerTy()) {
size_t byte_size = retType.getPrimitiveSizeInBits();
if (1 != byte_size) // For boolean type.
byte_size /= CHAR_BIT;
auto raw_value = ReadRawValue(reg_ctx, byte_size);
const bool is_signed = false; // IR Type doesn't provide this info.
if (!SetSizedInteger(value.GetScalar(), raw_value, byte_size, is_signed))
return ValueObjectSP();
}
// Pointer return type.
else if (retType.isPointerTy()) {
auto reg_info_r0 = reg_ctx->GetRegisterInfo(eRegisterKindGeneric,
LLDB_REGNUM_GENERIC_ARG1);
value.GetScalar() = reg_ctx->ReadRegisterAsUnsigned(reg_info_r0, 0);
value.SetValueType(Value::ValueType::Scalar);
}
// Floating point return type.
else if (retType.isFloatingPointTy()) {
const size_t byte_size = retType.getPrimitiveSizeInBits() / CHAR_BIT;
auto raw_value = ReadRawValue(reg_ctx, byte_size);
if (!SetSizedFloat(value.GetScalar(), raw_value, byte_size))
return ValueObjectSP();
}
// Unsupported return type.
else
return ValueObjectSP();
return ValueObjectConstResult::Create(thread.GetStackFrameAtIndex(0).get(),
value, ConstString(""));
}
bool ABISysV_arc::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::sp, 0);
// The previous PC is in the BLINK.
row->SetRegisterLocationToRegister(dwarf::pc, dwarf::blink, true);
unwind_plan.AppendRow(row);
// All other registers are the same.
unwind_plan.SetSourceName("arc at-func-entry default");
unwind_plan.SetSourcedFromCompiler(eLazyBoolNo);
return true;
}
bool ABISysV_arc::CreateDefaultUnwindPlan(UnwindPlan &unwind_plan) {
return false;
}
bool ABISysV_arc::RegisterIsVolatile(const RegisterInfo *reg_info) {
if (nullptr == reg_info)
return false;
// Volatile registers are: r0..r12.
uint32_t regnum = reg_info->kinds[eRegisterKindDWARF];
if (regnum <= 12)
return true;
static const std::string ra_reg_name = "blink";
return ra_reg_name == reg_info->name;
}
void ABISysV_arc::Initialize() {
PluginManager::RegisterPlugin(GetPluginNameStatic(),
"System V ABI for ARC targets", CreateInstance);
}
void ABISysV_arc::Terminate() {
PluginManager::UnregisterPlugin(CreateInstance);
}
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