265 lines
14 KiB
Rust
265 lines
14 KiB
Rust
use std::collections::BTreeMap;
|
|
|
|
use crate::{backend::{arm_instr::{ARMInstr, AddInstr, BInstr, BlInstr, CmpInstr, ConditionCode, LoadInstr, LoadPseudoInstr, MoveInstr, MulInstr, PopInstr, PushInstr, RegisterOrImm, RsbInstr, SDivInstr, StoreInstr, SubInstr}, register_allocator::{REG_R0, REG_R1, REG_R2, REG_R3, Register, RegisterAlloc, RegisterAllocator}, types::ARMAsmVar}, ir::types::{Function, IRInstr, MoveRValue, Variable, VariableOrIntLit, VariableType}};
|
|
use crate::ir::types::BinaryOp as IRBinaryOp;
|
|
use crate::ir::types::CmpOp as IRCmpOp;
|
|
use crate::ir::types::UnaryOp as IRUnaryOp;
|
|
|
|
pub const ARM_STACK_ALIGNMENT: usize = 8;
|
|
pub struct Generator {
|
|
instrs: Vec<ARMInstr>,
|
|
var_inited: Vec<ARMAsmVar>,
|
|
var_uninited: Vec<ARMAsmVar>,
|
|
register_allocator: RegisterAllocator,
|
|
}
|
|
|
|
const DEFAULT_VAR_ALIGN: usize = 4;
|
|
|
|
fn load_variable(variable: Variable, reg_allocator: &mut RegisterAllocator, var_index_to_stack_offset: &BTreeMap<usize, usize>, instrs: &mut Vec<ARMInstr>) -> RegisterAlloc {
|
|
match variable.var_type {
|
|
VariableType::Global => {
|
|
let var_alloc = reg_allocator.alloc(variable).expect("Ran out of registers");
|
|
let var_reg = var_alloc.reg;
|
|
// if !var_alloc.is_reused {
|
|
let address_alloc = reg_allocator.alloc_any().expect("Ran out of registers");
|
|
instrs.push(LoadPseudoInstr::new(address_alloc.reg, format!("global_var_{}", variable.index)));
|
|
instrs.push(LoadInstr::new(var_reg, address_alloc.reg, None));
|
|
// }
|
|
var_alloc
|
|
},
|
|
VariableType::ParamTemp => {
|
|
todo!()
|
|
},
|
|
_ => {
|
|
let stack_offset = var_index_to_stack_offset.get(&variable.index).expect("Variable not declared");
|
|
let var_alloc = reg_allocator.alloc(variable).expect("Ran out of registers");
|
|
// if !var_alloc.is_reused {
|
|
instrs.push(LoadInstr::new_stack(var_alloc.reg, *stack_offset as i32));
|
|
// }
|
|
var_alloc
|
|
}
|
|
}
|
|
}
|
|
|
|
fn save_variable(variable: Variable, reg: Register, reg_allocator: &mut RegisterAllocator, var_index_to_stack_offset: &BTreeMap<usize, usize>, instrs: &mut Vec<ARMInstr>) {
|
|
match variable.var_type {
|
|
VariableType::Global => {
|
|
let address_alloc = reg_allocator.alloc_any().expect("Ran out of registers");
|
|
instrs.push(LoadPseudoInstr::new(address_alloc.reg, format!("global_var_{}", variable.index)));
|
|
instrs.push(StoreInstr::new(reg, address_alloc.reg, None));
|
|
},
|
|
VariableType::ParamTemp => {
|
|
todo!()
|
|
},
|
|
_ => {
|
|
let stack_offset = var_index_to_stack_offset.get(&variable.index).expect("Variable not declared");
|
|
instrs.push(StoreInstr::new_stack(reg, *stack_offset as i32));
|
|
}
|
|
}
|
|
}
|
|
impl Generator {
|
|
pub fn new() -> Self {
|
|
Self {
|
|
instrs: Vec::new(),
|
|
var_inited: Vec::new(),
|
|
var_uninited: Vec::new(),
|
|
register_allocator: RegisterAllocator::new(),
|
|
}
|
|
}
|
|
pub fn emit(&mut self, ir_instrs: Vec<IRInstr>) {
|
|
for ir_instr in ir_instrs {
|
|
match ir_instr {
|
|
IRInstr::DefineFunc(func, args, body) => self.emit_func_def(func, args, body),
|
|
IRInstr::Declare(var) => self.emit_global_decl(var),
|
|
_ => unreachable!(),
|
|
}
|
|
}
|
|
}
|
|
pub fn to_text(&self) -> String {
|
|
let mut text = String::new();
|
|
text.push_str(".arch armv7ve\n.arm\n.fpu vfpv4\n");
|
|
for var in &self.var_uninited {
|
|
text.push_str(&format!(".comm {}, {}, {}\n", var.name, var.size, var.align));
|
|
}
|
|
for var in &self.var_inited {
|
|
text.push_str(&format!(".data\n.align {}\n.global {}\n.type {}, @object\n:{}\n", var.align, var.name, var.name, var.name));
|
|
text.push_str(&format!(".word 0\n"));
|
|
}
|
|
text.push_str(".text\n");
|
|
for instr in &self.instrs {
|
|
text.push_str(&format!("{}\n", instr));
|
|
}
|
|
text
|
|
}
|
|
|
|
|
|
fn emit_global_decl(&mut self, var: Variable) {
|
|
self.var_uninited.push(ARMAsmVar {
|
|
name: format!("global_var_{}", var.index),
|
|
size: var.data_type.size_in_bytes(),
|
|
align: DEFAULT_VAR_ALIGN,
|
|
});
|
|
}
|
|
|
|
fn emit_func_def(&mut self, func: Function, _args: Vec<Variable>, body: Vec<IRInstr>) {
|
|
self.instrs.push(ARMInstr::FunctionHead(func.name.clone(), 4)); // Assuming 4-byte alignment for simplicity
|
|
self.instrs.push(PushInstr::new_push_fp_lr());
|
|
self.instrs.push(MoveInstr::new_sp_to_fp());
|
|
self.emit_func(&func.name, body);
|
|
}
|
|
|
|
fn emit_func(&mut self, func_name: &str, instrs: Vec<IRInstr>) {
|
|
let mut encounter_entry = false;
|
|
let mut stack_size_needed = 0;
|
|
let mut var_index_to_stack_offset = BTreeMap::new();
|
|
for ir_instr in instrs {
|
|
match ir_instr {
|
|
IRInstr::Binary(dest, left, op, right) => self.emit_binary(dest, left, op, right, &var_index_to_stack_offset),
|
|
IRInstr::Exit(v) => {
|
|
if let Some(v) = v {
|
|
let ret_alloc = self.register_allocator.alloc_reg(REG_R0).expect("Ran out of registers");
|
|
let ret_reg = ret_alloc.reg;
|
|
let v_alloc = load_variable(v, &mut self.register_allocator, &var_index_to_stack_offset, &mut self.instrs);
|
|
self.instrs.push(MoveInstr::new_uncond(ret_reg, RegisterOrImm::Reg(v_alloc.reg)));
|
|
}
|
|
self.instrs.push(MoveInstr::new_fp_to_sp());
|
|
self.instrs.push(PopInstr::new_pop_fp_pc());
|
|
},
|
|
IRInstr::FuncCall(func, args, ret) => self.emit_func_call(func, args, ret, &var_index_to_stack_offset),
|
|
IRInstr::Move(dest, src) => self.emit_move(dest, src, &var_index_to_stack_offset),
|
|
IRInstr::Declare(variable) => {
|
|
assert!(!encounter_entry, "Variable declarations must come before entry instruction");
|
|
let size = variable.data_type.size_in_bytes();
|
|
stack_size_needed = (stack_size_needed + size).next_multiple_of(ARM_STACK_ALIGNMENT);
|
|
var_index_to_stack_offset.insert(variable.index, stack_size_needed);
|
|
},
|
|
IRInstr::Entry => {
|
|
assert!(!encounter_entry, "Multiple entry instructions are not allowed");
|
|
encounter_entry = true;
|
|
self.instrs.push(SubInstr::new_sp(stack_size_needed as i32));
|
|
},
|
|
IRInstr::DefineFunc(_, _, _) => unreachable!(),
|
|
IRInstr::Cmp(variable, left, cmp_op, right) => self.emit_cmp(variable, left, cmp_op, right, &var_index_to_stack_offset),
|
|
IRInstr::Unary(variable, unary_op, variable1) => self.emit_unary(variable, unary_op, variable1, &var_index_to_stack_offset),
|
|
IRInstr::Goto(index) => self.instrs.push(BInstr::new(format!("label_{}_{}", func_name, index))),
|
|
IRInstr::CondGoto(variable, true_label_index, false_label_index) => {
|
|
let variable_alloc = load_variable(variable, &mut self.register_allocator, &var_index_to_stack_offset, &mut self.instrs);
|
|
let variable_reg = variable_alloc.reg;
|
|
self.instrs.push(CmpInstr::new(variable_reg, RegisterOrImm::Imm(0)));
|
|
self.instrs.push(BInstr::new_cond(ConditionCode::Ne, format!("label_{}_{}", func_name, true_label_index)));
|
|
self.instrs.push(BInstr::new(format!("label_{}_{}", func_name, false_label_index)));
|
|
|
|
},
|
|
IRInstr::Label(index) => self.instrs.push(ARMInstr::Label(format!("label_{}_{}", func_name, index))),
|
|
}
|
|
}
|
|
}
|
|
fn emit_unary(&mut self, dest: Variable, unary_op: IRUnaryOp, variable: Variable, var_index_to_stack_offset: &BTreeMap<usize, usize>) {
|
|
let variable_alloc = load_variable(variable, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs);
|
|
let dest_alloc = self.register_allocator.alloc(dest).expect("Ran out of registers");
|
|
match unary_op {
|
|
IRUnaryOp::Neg => {
|
|
self.instrs.push(RsbInstr::new(dest_alloc.reg, variable_alloc.reg, RegisterOrImm::Imm(0)));
|
|
},
|
|
}
|
|
save_variable(dest, dest_alloc.reg, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs);
|
|
}
|
|
fn emit_cmp(&mut self, variable: Variable, left: VariableOrIntLit, cmp_op: IRCmpOp, right: VariableOrIntLit, var_index_to_stack_offset: &BTreeMap<usize, usize>) {
|
|
let left_alloc = match left {
|
|
VariableOrIntLit::Var(var) => {
|
|
load_variable(var, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs)
|
|
},
|
|
VariableOrIntLit::IntLit(lit) => {
|
|
let alloc = self.register_allocator.alloc_any().expect("Ran out of registers");
|
|
self.instrs.push(MoveInstr::new_uncond(alloc.reg, RegisterOrImm::Imm(lit)));
|
|
alloc
|
|
},
|
|
};
|
|
// TODO: check left == right
|
|
let right_alloc = match right {
|
|
VariableOrIntLit::Var(var) => {
|
|
load_variable(var, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs)
|
|
},
|
|
VariableOrIntLit::IntLit(lit) => {
|
|
let alloc = self.register_allocator.alloc_any().expect("Ran out of registers");
|
|
self.instrs.push(MoveInstr::new_uncond(alloc.reg, RegisterOrImm::Imm(lit)));
|
|
alloc
|
|
},
|
|
};
|
|
let variable_alloc = self.register_allocator.alloc(variable).expect("Ran out of registers");
|
|
let variable_reg = variable_alloc.reg;
|
|
self.instrs.push(CmpInstr::new(left_alloc.reg, RegisterOrImm::Reg(right_alloc.reg)));
|
|
self.instrs.push(MoveInstr::new_uncond(variable_reg, RegisterOrImm::Imm(0)));
|
|
self.instrs.push(MoveInstr::new_cond(cmp_op.into(), variable_reg, RegisterOrImm::Imm(1)));
|
|
save_variable(variable, variable_alloc.reg, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs);
|
|
}
|
|
fn emit_func_call(&mut self, func: Function, args: Vec<Variable>, ret: Option<Variable>, var_index_to_stack_offset: &BTreeMap<usize, usize>) {
|
|
|
|
self.instrs.push(PushInstr::new_push_caller_save());
|
|
if args.len() > 4 {
|
|
todo!("More than 4 arguments not supported yet");
|
|
}
|
|
const ARG_REGS: [Register; 4] = [REG_R0, REG_R1, REG_R2, REG_R3];
|
|
let mut arg_reg_allocs = Vec::new();
|
|
for (i, arg) in args.into_iter().enumerate() {
|
|
arg_reg_allocs.push(self.register_allocator.alloc_reg(ARG_REGS[i]).expect("Ran out of registers"));
|
|
let arg_alloc = load_variable(arg, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs);
|
|
self.instrs.push(MoveInstr::new_uncond(ARG_REGS[i], RegisterOrImm::Reg(arg_alloc.reg)));
|
|
}
|
|
self.instrs.push(BlInstr::new(func.name.clone()));
|
|
if let Some(ret) = ret {
|
|
save_variable(ret, REG_R0, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs);
|
|
}
|
|
|
|
|
|
self.instrs.push(PopInstr::new_pop_caller_save());
|
|
}
|
|
fn emit_move(&mut self, dest: Variable, src: MoveRValue, var_index_to_stack_offset: &BTreeMap<usize, usize>) {
|
|
let dest_alloc = self.register_allocator.alloc(dest).expect("Ran out of registers");
|
|
let dest_register = dest_alloc.reg;
|
|
match src {
|
|
MoveRValue::Var(variable) => {
|
|
let src_alloc = load_variable(variable, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs);
|
|
self.instrs.push(MoveInstr::new_uncond(dest_register, RegisterOrImm::Reg(src_alloc.reg)));
|
|
},
|
|
MoveRValue::ConstInt(literal_int) => self.instrs.push(MoveInstr::new_uncond(dest_register, RegisterOrImm::Imm(literal_int))),
|
|
};
|
|
save_variable(dest, dest_alloc.reg, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs);
|
|
}
|
|
fn emit_binary(&mut self, dest: Variable, left: Variable, op: IRBinaryOp, right: Variable, var_index_to_stack_offset: &BTreeMap<usize, usize>) {
|
|
let dest_alloc = self.register_allocator.alloc(dest).expect("Ran out of registers");
|
|
let dest_reg = dest_alloc.reg;
|
|
// should consider left == right
|
|
let left_alloc = load_variable(left, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs);
|
|
let (_right_alloc, right_reg) = if left != right {
|
|
let right_alloc = load_variable(right, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs);
|
|
let right_reg = right_alloc.reg;
|
|
(Some(right_alloc), right_reg)
|
|
} else {
|
|
(None, left_alloc.reg)
|
|
};
|
|
match op {
|
|
IRBinaryOp::Add => {
|
|
self.instrs.push(AddInstr::new(dest_reg, left_alloc.reg, RegisterOrImm::Reg(right_reg)));
|
|
},
|
|
IRBinaryOp::Sub => {
|
|
self.instrs.push(SubInstr::new(dest_reg, left_alloc.reg, RegisterOrImm::Reg(right_reg)));
|
|
},
|
|
IRBinaryOp::Mul => {
|
|
self.instrs.push(MulInstr::new(dest_reg, left_alloc.reg, RegisterOrImm::Reg(right_reg)));
|
|
},
|
|
IRBinaryOp::Div => {
|
|
self.instrs.push(SDivInstr::new(dest_reg, left_alloc.reg, RegisterOrImm::Reg(right_reg)));
|
|
},
|
|
IRBinaryOp::Mod => {
|
|
let temp_alloc = self.register_allocator.alloc_any().expect("Ran out of registers");
|
|
let temp_reg = temp_alloc.reg;
|
|
self.instrs.push(SDivInstr::new(temp_reg, left_alloc.reg, RegisterOrImm::Reg(right_reg)));
|
|
self.instrs.push(MulInstr::new(temp_reg, temp_reg, RegisterOrImm::Reg(right_reg)));
|
|
self.instrs.push(SubInstr::new(dest_reg, left_alloc.reg, RegisterOrImm::Reg(temp_reg)));
|
|
},
|
|
}
|
|
save_variable(dest, dest_alloc.reg, &mut self.register_allocator, var_index_to_stack_offset, &mut self.instrs);
|
|
}
|
|
|
|
} |