elna/backend/riscv.cpp

370 lines
16 KiB
C++
Raw Normal View History

2024-03-07 09:15:11 +01:00
#include "elna/backend/riscv.hpp"
2024-03-01 10:13:55 +01:00
#include <memory>
2024-02-28 16:18:39 +01:00
2024-03-09 08:36:07 +01:00
namespace elna::riscv
2024-02-28 16:18:39 +01:00
{
2024-03-09 08:36:07 +01:00
instruction::instruction(base_opcode opcode)
2024-02-28 16:18:39 +01:00
{
2024-03-09 08:36:07 +01:00
this->representation = static_cast<std::underlying_type<base_opcode>::type>(opcode);
2024-02-28 16:18:39 +01:00
}
2024-03-09 08:36:07 +01:00
instruction& instruction::i(x_register rd, funct3_t funct3, x_register rs1, std::uint32_t immediate)
2024-02-28 16:18:39 +01:00
{
2024-03-09 08:36:07 +01:00
this->representation |= (static_cast<std::underlying_type<x_register>::type>(rd) << 7)
| (static_cast<std::underlying_type<funct3_t>::type>(funct3) << 12)
| (static_cast<std::underlying_type<x_register>::type>(rs1) << 15)
2024-02-28 16:18:39 +01:00
| (immediate << 20);
return *this;
}
2024-03-17 01:00:44 +01:00
instruction& instruction::s(std::uint32_t imm, funct3_t funct3, x_register rs1, x_register rs2)
2024-02-28 16:18:39 +01:00
{
2024-03-17 01:00:44 +01:00
this->representation |= ((imm & 0x1f) << 7)
2024-03-09 08:36:07 +01:00
| (static_cast<std::underlying_type<funct3_t>::type>(funct3) << 12)
| (static_cast<std::underlying_type<x_register>::type>(rs1) << 15)
| (static_cast<std::underlying_type<x_register>::type>(rs2) << 20)
2024-03-17 01:00:44 +01:00
| ((imm & 0xfe0) << 20);
return *this;
}
instruction& instruction::b(std::uint32_t imm, funct3_t funct3, x_register rs1, x_register rs2)
{
this->representation |= ((imm & 0x800) >> 4) | ((imm & 0x1e) << 7)
| (static_cast<std::underlying_type<funct3_t>::type>(funct3) << 12)
| (static_cast<std::underlying_type<x_register>::type>(rs1) << 15)
| (static_cast<std::underlying_type<x_register>::type>(rs2) << 20)
| ((imm & 0x7e0) << 20) | ((imm & 0x1000) << 19);
2024-02-28 16:18:39 +01:00
return *this;
}
2024-03-09 08:36:07 +01:00
instruction& instruction::r(x_register rd, funct3_t funct3, x_register rs1, x_register rs2, funct7_t funct7)
2024-02-28 16:18:39 +01:00
{
2024-03-09 08:36:07 +01:00
this->representation |= (static_cast<std::underlying_type<x_register>::type>(rd) << 7)
| (static_cast<std::underlying_type<funct3_t>::type>(funct3) << 12)
| (static_cast<std::underlying_type<x_register>::type>(rs1) << 15)
| (static_cast<std::underlying_type<x_register>::type>(rs2) << 20)
| (static_cast<std::underlying_type<funct7_t>::type>(funct7) << 25);
2024-02-28 16:18:39 +01:00
return *this;
}
2024-03-09 08:36:07 +01:00
instruction& instruction::u(x_register rd, std::uint32_t imm)
2024-02-28 16:18:39 +01:00
{
2024-03-09 08:36:07 +01:00
this->representation |= (static_cast<std::underlying_type<x_register>::type>(rd) << 7) | (imm << 12);
2024-02-28 16:18:39 +01:00
return *this;
}
2024-03-17 01:00:44 +01:00
instruction& instruction::j(x_register rd, std::uint32_t imm)
{
this->representation |= (static_cast<std::underlying_type<x_register>::type>(rd) << 7)
| (imm & 0xff000) | ((imm & 0x800) << 9) | ((imm & 0x7fe) << 20) | ((imm & 0x100000) << 11);
return *this;
}
2024-03-09 08:36:07 +01:00
const std::byte *instruction::cbegin() const
2024-02-28 16:18:39 +01:00
{
2024-03-09 08:36:07 +01:00
return reinterpret_cast<const std::byte *>(&this->representation);
2024-03-03 13:11:39 +01:00
}
2024-03-09 08:36:07 +01:00
const std::byte *instruction::cend() const
2024-03-03 13:11:39 +01:00
{
2024-03-09 08:36:07 +01:00
return reinterpret_cast<const std::byte *>(&this->representation) + sizeof(this->representation);
2024-02-28 16:18:39 +01:00
}
2024-03-19 09:35:50 +01:00
visitor::visitor(std::shared_ptr<source::writer> writer)
: writer(writer)
{
}
2024-03-20 17:56:38 +01:00
void visitor::generate_intrinsics()
{
this->writer->sink("printf");
{
auto format_string = this->writer->sink(reinterpret_cast<const std::byte *>("%c\n\0"), 4);
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::sp, funct3_t::addi, x_register::sp, -8));
this->instructions.push_back(instruction(base_opcode::store)
.s(4, funct3_t::sw, x_register::sp, x_register::s0));
this->instructions.push_back(instruction(base_opcode::store)
.s(0, funct3_t::sw, x_register::sp, x_register::ra));
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::s0, funct3_t::addi, x_register::sp, -8));
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::a1, funct3_t::addi, x_register::zero, 't'));
this->instructions.push_back(instruction(base_opcode::branch)
.b(8, funct3_t::bne, x_register::zero, x_register::a0));
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::a1, funct3_t::addi, x_register::zero, 'f'));
relocate(format_string, address_t::high20);
this->instructions.push_back(instruction(base_opcode::lui).u(x_register::a5, 0));
relocate(format_string, address_t::lower12i);
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::a0, funct3_t::addi, x_register::a5, 0));
relocate("printf", address_t::text);
this->instructions.push_back(instruction(base_opcode::auipc).u(x_register::ra, 0));
this->instructions.push_back(instruction(base_opcode::jalr)
.i(x_register::ra, funct3_t::jalr, x_register::ra, 0));
this->instructions.push_back(instruction(base_opcode::load)
.i(x_register::s0, funct3_t::lw, x_register::sp, 4));
this->instructions.push_back(instruction(base_opcode::load)
.i(x_register::ra, funct3_t::lw, x_register::sp, 0));
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::sp, funct3_t::addi, x_register::sp, 8));
this->instructions.push_back(instruction(base_opcode::jalr)
.i(x_register::zero, funct3_t::jalr, x_register::ra, 0));
this->writer->sink("writeb", reinterpret_cast<const std::byte *>(this->instructions.data()),
this->instructions.size() * sizeof(instruction));
this->instructions.clear();
}
{
auto format_string = this->writer->sink(reinterpret_cast<const std::byte *>("%d\n\0"), 4);
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::sp, funct3_t::addi, x_register::sp, -8));
this->instructions.push_back(instruction(base_opcode::store)
.s(4, funct3_t::sw, x_register::sp, x_register::s0));
this->instructions.push_back(instruction(base_opcode::store)
.s(0, funct3_t::sw, x_register::sp, x_register::ra));
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::s0, funct3_t::addi, x_register::sp, -8));
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::a1, funct3_t::addi, x_register::a0, 0));
relocate(format_string, address_t::high20);
this->instructions.push_back(instruction(base_opcode::lui).u(x_register::a5, 0));
relocate(format_string, address_t::lower12i);
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::a0, funct3_t::addi, x_register::a5, 0));
relocate("printf", address_t::text);
this->instructions.push_back(instruction(base_opcode::auipc).u(x_register::ra, 0));
this->instructions.push_back(instruction(base_opcode::jalr)
.i(x_register::ra, funct3_t::jalr, x_register::ra, 0));
this->instructions.push_back(instruction(base_opcode::load)
.i(x_register::s0, funct3_t::lw, x_register::sp, 4));
this->instructions.push_back(instruction(base_opcode::load)
.i(x_register::ra, funct3_t::lw, x_register::sp, 0));
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::sp, funct3_t::addi, x_register::sp, 8));
this->instructions.push_back(instruction(base_opcode::jalr)
.i(x_register::zero, funct3_t::jalr, x_register::ra, 0));
this->writer->sink("writei", reinterpret_cast<const std::byte *>(this->instructions.data()),
this->instructions.size() * sizeof(instruction));
this->instructions.clear();
}
}
void visitor::relocate(std::string_view name, address_t target)
{
this->references.push_back(reference());
this->references.back().name = name;
this->references.back().offset = writer->size() + instructions.size() * 4;
this->references.back().target = target;
}
2024-03-11 10:43:26 +01:00
void visitor::visit(source::declaration *declaration)
{
}
2024-03-20 17:56:38 +01:00
void visitor::visit(source::constant_definition *definition)
{
}
void visitor::visit(source::procedure_definition *definition)
2024-02-28 16:18:39 +01:00
{
}
2024-03-09 08:36:07 +01:00
void visitor::visit(source::block *block)
2024-02-28 16:18:39 +01:00
{
2024-03-11 10:43:26 +01:00
this->instructions.push_back(instruction(base_opcode::opImm));
this->instructions.push_back(instruction(base_opcode::store));
this->instructions.push_back(instruction(base_opcode::store));
this->instructions.push_back(instruction(base_opcode::opImm));
2024-03-14 08:52:45 +01:00
table = block->table();
block->body().accept(this);
2024-03-01 10:13:55 +01:00
2024-03-11 10:43:26 +01:00
// Set the return value (0).
this->instructions.push_back(instruction(base_opcode::op)
.r(x_register::a0, funct3_t::_and, x_register::zero, x_register::zero));
2024-02-28 16:18:39 +01:00
// Prologue.
2024-03-14 08:52:45 +01:00
auto main_symbol =
std::dynamic_pointer_cast<source::procedure_info>(table->lookup("main"));
const uint stack_size = static_cast<std::uint32_t>(variable_counter * 4 + 8 + main_symbol->stack_size());
2024-03-11 10:43:26 +01:00
this->instructions[0].i(x_register::sp, funct3_t::addi, x_register::sp, -stack_size);
this->instructions[1].s(stack_size - 4, funct3_t::sw, x_register::sp, x_register::s0);
this->instructions[2].s(stack_size - 8, funct3_t::sw, x_register::sp, x_register::ra);
this->instructions[3].i(x_register::s0, funct3_t::addi, x_register::sp, stack_size);
// Epilogue.
this->instructions.push_back(instruction(base_opcode::load)
.i(x_register::s0, funct3_t::lw, x_register::sp, stack_size - 4));
this->instructions.push_back(instruction(base_opcode::load)
.i(x_register::ra, funct3_t::lw, x_register::sp, stack_size - 8));
this->instructions.push_back(instruction(base_opcode::opImm)
.i(x_register::sp, funct3_t::addi, x_register::sp, stack_size));
this->instructions.push_back(instruction(base_opcode::jalr)
.i(x_register::zero, funct3_t::jalr, x_register::ra, 0));
}
void visitor::visit(source::program *program)
{
2024-03-20 17:56:38 +01:00
generate_intrinsics();
2024-03-19 09:35:50 +01:00
visit(dynamic_cast<source::block *>(program));
this->writer->sink("main", reinterpret_cast<const std::byte *>(this->instructions.data()),
this->instructions.size() * sizeof(instruction));
}
void visitor::visit(source::call_statement *statement)
{
statement->arguments().accept(this);
2024-03-20 17:56:38 +01:00
relocate(statement->name(), address_t::text);
2024-03-09 08:36:07 +01:00
this->instructions.push_back(instruction(base_opcode::auipc).u(x_register::ra, 0));
this->instructions.push_back(instruction(base_opcode::jalr)
.i(x_register::ra, funct3_t::jalr, x_register::ra, 0));
2024-03-11 10:43:26 +01:00
}
2024-02-28 16:18:39 +01:00
2024-03-11 10:43:26 +01:00
void visitor::visit(source::compound_statement *statement)
{
for (auto& nested_statement : statement->statements())
{
nested_statement->accept(this);
}
2024-02-28 16:18:39 +01:00
}
2024-03-14 08:52:45 +01:00
void visitor::visit(source::assign_statement *statement)
2024-03-01 10:13:55 +01:00
{
2024-03-14 08:52:45 +01:00
const auto free_register = this->register_in_use ? x_register::a0 : x_register::t0;
auto symbol = table->lookup(statement->lvalue());
auto variable_symbol = std::dynamic_pointer_cast<source::variable_info>(symbol);
statement->rvalue().accept(this);
this->instructions.push_back(instruction(base_opcode::store)
.s(variable_symbol->offset, funct3_t::sw, x_register::s0, x_register::a0));
2024-02-28 16:18:39 +01:00
}
2024-03-17 01:00:44 +01:00
void visitor::visit(source::if_statement *statement)
{
statement->prerequisite().accept(this);
2024-03-20 17:56:38 +01:00
const auto free_register = this->register_in_use ? x_register::a0 : x_register::t0;
2024-03-17 01:00:44 +01:00
auto before_branch = instructions.size();
instructions.push_back(instruction(base_opcode::branch));
statement->body().accept(this);
instructions[before_branch]
2024-03-20 17:56:38 +01:00
.b((instructions.size() - before_branch) * 4 - 4, funct3_t::beq, x_register::zero, free_register);
2024-03-17 01:00:44 +01:00
}
void visitor::visit(source::while_statement *statement)
{
statement->prerequisite().accept(this);
statement->body().accept(this);
}
2024-03-09 08:36:07 +01:00
void visitor::visit(source::variable_expression *variable)
2024-02-28 16:18:39 +01:00
{
2024-03-09 08:36:07 +01:00
const auto free_register = this->register_in_use ? x_register::a0 : x_register::t0;
2024-02-28 16:18:39 +01:00
2024-03-14 08:52:45 +01:00
auto symbol = table->lookup(variable->name());
if (auto constant_symbol = std::dynamic_pointer_cast<source::constant_info>(symbol))
{
this->instructions.push_back(
instruction(base_opcode::opImm) // movl $x, %eax; where $x is a number.
.i(free_register, funct3_t::addi, x_register::zero, constant_symbol->value())
);
}
else if (auto variable_symbol = std::dynamic_pointer_cast<source::variable_info>(symbol))
{
this->instructions.push_back(
instruction(base_opcode::store)
.i(free_register, funct3_t::lw, x_register::s0, variable_symbol->offset)
);
}
2024-02-28 16:18:39 +01:00
}
2024-03-09 08:36:07 +01:00
void visitor::visit(source::binary_expression *expression)
2024-02-28 16:18:39 +01:00
{
2024-03-09 08:36:07 +01:00
const auto lhs_register = this->register_in_use ? x_register::a0 : x_register::t0;
2024-03-01 10:13:55 +01:00
2024-03-09 08:36:07 +01:00
this->register_in_use = true;
expression->lhs().accept(this);
2024-03-01 10:13:55 +01:00
2024-03-07 09:15:11 +01:00
this->instructions.push_back( // movl %eax, -x(%rbp); where x is a number.
2024-03-09 08:36:07 +01:00
instruction(base_opcode::store)
.s(static_cast<std::uint32_t>(this->variable_counter * 4), funct3_t::sw, x_register::sp, x_register::a0)
2024-03-07 09:15:11 +01:00
);
2024-03-09 08:36:07 +01:00
auto lhs_stack_position = ++this->variable_counter;
2024-03-01 10:13:55 +01:00
2024-03-09 08:36:07 +01:00
this->register_in_use = false;
expression->rhs().accept(this);
2024-02-28 16:18:39 +01:00
2024-03-09 08:36:07 +01:00
this->instructions.push_back(instruction(base_opcode::load)
.i(x_register::a0, funct3_t::lw, x_register::sp,
2024-03-07 09:15:11 +01:00
static_cast<std::int8_t>((lhs_stack_position - 1) * 4))
);
2024-03-01 10:13:55 +01:00
2024-02-28 16:18:39 +01:00
// Calculate the result and assign it to a variable on the stack.
switch (expression->operation())
2024-02-28 16:18:39 +01:00
{
case source::binary_operator::sum:
2024-03-09 08:36:07 +01:00
this->instructions.push_back(instruction(base_opcode::op)
.r(lhs_register, funct3_t::add, x_register::a0, x_register::t0));
2024-02-28 16:18:39 +01:00
break;
case source::binary_operator::subtraction:
2024-03-09 08:36:07 +01:00
this->instructions.push_back(instruction(base_opcode::op)
.r(lhs_register, funct3_t::sub, x_register::a0, x_register::t0, funct7_t::sub));
2024-02-28 16:18:39 +01:00
break;
case source::binary_operator::multiplication:
2024-03-09 08:36:07 +01:00
this->instructions.push_back(instruction(base_opcode::op)
.r(lhs_register, funct3_t::mul, x_register::a0, x_register::t0, funct7_t::muldiv));
break;
case source::binary_operator::division:
this->instructions.push_back(instruction(base_opcode::op)
.r(lhs_register, funct3_t::div, x_register::a0, x_register::t0, funct7_t::muldiv));
2024-03-03 13:11:39 +01:00
break;
2024-02-28 16:18:39 +01:00
}
2024-03-01 10:13:55 +01:00
}
2024-03-17 01:00:44 +01:00
void visitor::visit(source::integer_literal *number)
{
const auto free_register = this->register_in_use ? x_register::a0 : x_register::t0;
this->instructions.push_back(
instruction(base_opcode::opImm) // movl $x, %eax; where $x is a number.
.i(free_register, funct3_t::addi, x_register::zero, number->number())
);
}
void visitor::visit(source::boolean_literal *number)
{
const auto free_register = this->register_in_use ? x_register::a0 : x_register::t0;
this->instructions.push_back(
instruction(base_opcode::opImm) // movl $x, %eax; where $x is a number.
.i(free_register, funct3_t::addi, x_register::zero, number->boolean())
);
}
2024-02-28 16:18:39 +01:00
}