Files
nixjit/src/jit/mod.rs
imxyy_soope_ 2a19ddb279 feat: no clone in JIT
IMPORTANT: should not drop or create values in JIT anymore
2025-05-21 20:48:56 +08:00

445 lines
15 KiB
Rust

use std::rc::Rc;
use inkwell::OptimizationLevel;
use inkwell::builder::Builder;
use inkwell::context::Context;
use inkwell::execution_engine::{ExecutionEngine, JitFunction};
use inkwell::module::Module;
use inkwell::values::{BasicValueEnum, FunctionValue, PointerValue};
use crate::bytecode::{Func, OpCode, UnOp};
use crate::error::*;
use crate::stack::Stack;
use crate::ty::common::Const;
use crate::ty::internal::{Thunk, Value};
use crate::vm::{VM, VmEnv};
mod helpers;
use helpers::Helpers;
#[cfg(test)]
mod test;
const STACK_SIZE: usize = 8 * 1024 / size_of::<Value>();
#[repr(u64)]
#[derive(Debug, Clone, Copy)]
pub enum ValueTag {
Int,
Float,
String,
Bool,
AttrSet,
List,
Function,
Thunk,
Path,
Null,
}
#[repr(C)]
#[derive(Clone, Copy)]
pub struct JITValue {
tag: ValueTag,
data: JITValueData,
}
#[repr(C)]
#[derive(Clone, Copy)]
pub union JITValueData {
int: i64,
float: f64,
bool: bool,
ptr: *const (),
}
impl<'jit: 'vm, 'vm> From<JITValue> for Value<'jit, 'vm> {
fn from(value: JITValue) -> Self {
use ValueTag::*;
match value.tag {
List | AttrSet | String | Function | Thunk | Path => unsafe {
Rc::increment_strong_count(value.data.ptr);
},
_ => (),
}
match value.tag {
Int => Value::Const(Const::Int(unsafe { value.data.int })),
Null => Value::Const(Const::Null),
Function => Value::Func(unsafe { Rc::from_raw(value.data.ptr as *const _) }),
Thunk => Value::Thunk(unsafe { Rc::from_raw(value.data.ptr as *const _) }),
_ => todo!("not implemented for {:?}", value.tag),
}
}
}
impl From<&Value<'_, '_>> for JITValue {
fn from(value: &Value<'_, '_>) -> Self {
match value {
Value::Const(Const::Int(int)) => JITValue {
tag: ValueTag::Int,
data: JITValueData { int: *int },
},
Value::Func(func) => JITValue {
tag: ValueTag::Function,
data: JITValueData {
ptr: Rc::as_ptr(func) as *const _,
},
},
Value::Thunk(thunk) => JITValue {
tag: ValueTag::Thunk,
data: JITValueData {
ptr: Rc::as_ptr(thunk) as *const _,
},
},
_ => todo!(),
}
}
}
impl From<Value<'_, '_>> for JITValue {
fn from(value: Value<'_, '_>) -> Self {
match value {
Value::Const(Const::Int(int)) => JITValue {
tag: ValueTag::Int,
data: JITValueData { int },
},
Value::Func(func) => JITValue {
tag: ValueTag::Function,
data: JITValueData {
ptr: Rc::into_raw(func) as *const _,
},
},
Value::Thunk(thunk) => JITValue {
tag: ValueTag::Thunk,
data: JITValueData {
ptr: Rc::into_raw(thunk) as *const _,
},
},
_ => todo!(),
}
}
}
pub type JITFunc<'jit, 'vm> =
unsafe extern "C" fn(*const VM<'jit>, *const VmEnv<'jit, 'vm>) -> JITValue;
pub struct JITContext<'ctx> {
context: &'ctx Context,
module: Module<'ctx>,
builder: Builder<'ctx>,
execution_engine: ExecutionEngine<'ctx>,
helpers: Helpers<'ctx>,
}
impl<'vm, 'ctx: 'vm> JITContext<'ctx> {
pub fn new(context: &'ctx Context) -> Self {
let module = context.create_module("nixjit");
let execution_engine = module
.create_jit_execution_engine(OptimizationLevel::Default)
.unwrap();
let helpers = Helpers::new(context, &module, &execution_engine);
JITContext {
execution_engine,
builder: context.create_builder(),
context,
module,
helpers,
}
}
pub fn new_ptr<T>(&self, ptr: *const T) -> PointerValue<'ctx> {
self.builder
.build_int_to_ptr(
self.helpers.int_type.const_int(ptr as _, false),
self.helpers.ptr_type,
"ptrconv",
)
.unwrap()
}
pub fn compile_function(
&self,
func: &Func,
vm: &'vm VM<'_>,
) -> Result<JitFunction<'ctx, JITFunc<'ctx, 'vm>>> {
let mut stack = Stack::<_, STACK_SIZE>::new();
let mut iter = func.opcodes.iter().copied();
let func_ = self
.module
.add_function("nixjit_function", self.helpers.func_type, None);
let env = func_.get_nth_param(1).unwrap().into_pointer_value();
let entry = self.context.append_basic_block(func_, "entry");
self.builder.position_at_end(entry);
self.build_expr(&mut iter, vm, env, &mut stack, func_, func.opcodes.len())?;
assert_eq!(stack.len(), 1);
let value = stack.pop();
let exit = self.context.append_basic_block(func_, "exit");
self.builder.build_unconditional_branch(exit)?;
self.builder.position_at_end(exit);
self.builder.build_return(Some(&value))?;
if func_.verify(true) {
unsafe {
let name = func_.get_name().to_str().unwrap();
let addr = self.execution_engine.get_function(name).unwrap();
Ok(addr)
}
} else {
todo!()
}
}
fn build_expr<const CAP: usize>(
&self,
iter: &mut impl Iterator<Item = OpCode>,
vm: &'vm VM<'_>,
env: PointerValue<'ctx>,
stack: &mut Stack<BasicValueEnum<'ctx>, CAP>,
func: FunctionValue<'ctx>,
mut length: usize,
) -> Result<usize> {
while length > 1 {
let opcode = iter.next().unwrap();
let br = self.single_op(opcode, vm, env, stack)?;
length -= 1;
if br > 0 {
let consq = self.context.append_basic_block(func, "consq");
let alter = self.context.append_basic_block(func, "alter");
let cont = self.context.append_basic_block(func, "cont");
let cond = self
.builder
.build_alloca(self.helpers.value_type, "cond_alloca")?;
let result = self
.builder
.build_alloca(self.helpers.value_type, "result_alloca")?;
self.builder.build_store(cond, stack.pop())?;
self.builder.build_conditional_branch(
self.builder
.build_load(
self.context.bool_type(),
self.builder.build_struct_gep(
self.helpers.value_type,
cond,
1,
"gep_cond",
)?,
"load_cond",
)?
.into_int_value(),
consq,
alter,
)?;
length -= br;
self.builder.position_at_end(consq);
let br = self.build_expr(iter, vm, env, stack, func, br)?;
self.builder.build_store(result, stack.pop())?;
self.builder.build_unconditional_branch(cont)?;
length -= br;
self.builder.position_at_end(alter);
self.build_expr(iter, vm, env, stack, func, br)?;
self.builder.build_store(result, stack.pop())?;
self.builder.build_unconditional_branch(cont)?;
self.builder.position_at_end(cont);
stack.push(self.builder.build_load(
self.helpers.value_type,
result,
"load_result",
)?)?;
}
}
if length > 0 {
self.single_op(iter.next().unwrap(), vm, env, stack)
} else {
Ok(0)
}
}
#[inline(always)]
fn single_op<const CAP: usize>(
&self,
opcode: OpCode,
vm: &'vm VM<'_>,
env: PointerValue<'ctx>,
stack: &mut Stack<BasicValueEnum<'ctx>, CAP>,
) -> Result<usize> {
match opcode {
OpCode::Const { idx } => {
use Const::*;
match vm.get_const(idx) {
Int(int) => stack.push(self.helpers.new_int(int))?,
Float(float) => stack.push(self.helpers.new_float(float))?,
Bool(bool) => stack.push(self.helpers.new_bool(bool))?,
String(string) => stack.push(self.helpers.const_string(string.as_ptr()))?,
Null => stack.push(self.helpers.new_null())?,
}
}
OpCode::LoadThunk { idx } => stack.push(
self.helpers
.new_thunk(Rc::into_raw(Rc::new(Thunk::new(vm.get_thunk(idx))))),
)?,
OpCode::CaptureEnv => {
let thunk = *stack.tos()?;
self.builder.build_direct_call(
self.helpers.capture_env,
&[thunk.into(), env.into()],
"call_capture_env",
)?;
}
OpCode::UnOp { op } => {
use UnOp::*;
let rhs = stack.pop();
stack.push(match op {
Neg => self
.builder
.build_direct_call(self.helpers.neg, &[rhs.into(), env.into()], "call_neg")?
.try_as_basic_value()
.left()
.unwrap(),
Not => self
.builder
.build_direct_call(self.helpers.not, &[rhs.into(), env.into()], "call_neg")?
.try_as_basic_value()
.left()
.unwrap(),
})?
}
OpCode::BinOp { op } => {
use crate::bytecode::BinOp;
let rhs = stack.pop();
let lhs = stack.pop();
match op {
BinOp::Add => {
let result = self
.builder
.build_direct_call(
self.helpers.add,
&[lhs.into(), rhs.into()],
"call_add",
)?
.try_as_basic_value()
.left()
.unwrap();
stack.push(result)?;
}
BinOp::Sub => {
let result = self
.builder
.build_direct_call(
self.helpers.sub,
&[lhs.into(), rhs.into()],
"call_add",
)?
.try_as_basic_value()
.left()
.unwrap();
stack.push(result)?;
}
BinOp::Eq => {
let result = self
.builder
.build_direct_call(
self.helpers.eq,
&[lhs.into(), rhs.into()],
"call_eq",
)?
.try_as_basic_value()
.left()
.unwrap();
stack.push(result)?;
}
BinOp::Or => {
let result = self
.builder
.build_direct_call(
self.helpers.or,
&[lhs.into(), rhs.into()],
"call_or",
)?
.try_as_basic_value()
.left()
.unwrap();
stack.push(result)?;
}
_ => todo!("BinOp::{:?} not implemented in JIT", op),
}
}
OpCode::LookUp { sym } => stack.push(
self.builder
.build_direct_call(
self.helpers.lookup,
&[
self.helpers
.ptr_int_type
.const_int(sym as u64, false)
.into(),
env.into(),
],
"call_lookup",
)
.unwrap()
.try_as_basic_value()
.left()
.unwrap(),
)?,
OpCode::Call { arity } => {
let args = self.builder.build_array_malloc(
self.helpers.value_type,
self.helpers.int_type.const_int(arity as u64, false),
"malloc_args",
)?;
for i in 0..arity {
let ptr = unsafe {
self.builder.build_in_bounds_gep(
self.helpers.value_type,
args,
&[self.helpers.int_type.const_int(i as u64, false)],
"gep_arg",
)?
};
self.builder.build_store(ptr, stack.pop())?;
}
let func = self
.builder
.build_direct_call(
self.helpers.force,
&[stack.pop().into(), self.new_ptr(vm).into()],
"force",
)?
.try_as_basic_value()
.left()
.unwrap();
let ret = self
.builder
.build_direct_call(
self.helpers.call,
&[
func.into(),
args.into(),
self.helpers
.ptr_int_type
.const_int(arity as u64, false)
.into(),
self.new_ptr(vm).into(),
],
"call",
)?
.try_as_basic_value()
.left()
.unwrap();
stack.push(ret)?;
}
OpCode::JmpIfFalse { step } => return Ok(step),
OpCode::Jmp { step } => return Ok(step),
_ => todo!("{opcode:?} not implemented"),
}
Ok(0)
}
}