Files
kraken/slj/src/lib.rs

1453 lines
60 KiB
Rust

use std::collections::{BTreeSet,BTreeMap};
use std::fmt;
use anyhow::{anyhow,bail,Result};
use std::sync::Mutex;
use std::marker::PhantomData;
use std::ops::{Deref,DerefMut};
use std::ptr::{self, NonNull};
use std::mem::{self, ManuallyDrop};
use std::alloc::{self, Layout};
use std::cell::Cell;
use cranelift::codegen::ir::UserFuncName;
use cranelift::prelude::*;
use cranelift_codegen::settings::{self, Configurable};
use cranelift_jit::{JITBuilder, JITModule};
use cranelift_module::{default_libcall_names, Linkage, Module, FuncId};
use once_cell::sync::Lazy;
extern "C" fn rust_add1(x: Form, y: Form) -> Form {
println!("Add 1");
Form::new_int(x.int().unwrap() + y.int().unwrap())
}
extern "C" fn rust_add2(x: isize, y: isize) -> isize {
println!("Add 2");
x + y
}
// https://github.com/bytecodealliance/wasmtime/blob/main/cranelift/jit/examples/jit-minimal.rs
pub struct JIT {
module: JITModule,
ctx: codegen::Context,
func_ctx: FunctionBuilderContext,
int: Type,
}
impl JIT {
pub fn new() -> Self {
let mut flag_builder = settings::builder();
flag_builder.set("use_colocated_libcalls", "false").unwrap(); //?
flag_builder.set("is_pic", "false").unwrap();
flag_builder.set("preserve_frame_pointers", "true").unwrap(); // needed for Tail CallConv
//println!("{:?}", flag_builder.iter().collect::<Vec<_>>());
//flag_builder.set("tail", "true").unwrap();
let isa_builder = cranelift_native::builder().unwrap_or_else(|msg| {
panic!("host machine is not supported: {}", msg);
});
let isa = isa_builder.finish(settings::Flags::new(flag_builder)).unwrap();
let mut jb = JITBuilder::with_isa(isa, default_libcall_names());
jb.symbol("rust_add1", rust_add1 as *const u8);
jb.symbol("rust_add2", rust_add2 as *const u8);
let mut module = JITModule::new(jb);
let int = module.target_config().pointer_type();
let mut ctx = module.make_context();
let mut func_ctx = FunctionBuilderContext::new();
Self { module, ctx, func_ctx, int }
}
// returns the id for the inner and the pointer for the outer
pub fn compile_with_wrapper(&mut self) -> (FuncId, extern "C" fn (Form) -> Form) {
let mut sig_a = self.module.make_signature();
sig_a.call_conv = isa::CallConv::Tail;
sig_a.params.push(AbiParam::new(self.int));
sig_a.returns.push(AbiParam::new(self.int));
let func_a = self.module.declare_function("a", Linkage::Local, &sig_a).unwrap();
let mut sig_b = self.module.make_signature();
//sig_b.call_conv = isa::CallConv::Tail;
sig_b.params.push(AbiParam::new(self.int));
sig_b.returns.push(AbiParam::new(self.int));
let func_b = self.module.declare_function("b", Linkage::Local, &sig_b).unwrap();
self.ctx.func.signature = sig_a;
self.ctx.func.name = UserFuncName::user(0, func_a.as_u32());
{
let mut bcx: FunctionBuilder = FunctionBuilder::new(&mut self.ctx.func, &mut self.func_ctx);
let block = bcx.create_block();
bcx.switch_to_block(block);
bcx.append_block_params_for_function_params(block);
let param = bcx.block_params(block)[0];
let cst = bcx.ins().iconst(self.int, 3 << 3);
let add = bcx.ins().iadd(cst, param);
let cr = {
let mut sig = self.module.make_signature();
sig.params.push(AbiParam::new(self.int));
sig.params.push(AbiParam::new(self.int));
sig.returns.push(AbiParam::new(self.int));
//let callee = module.declare_function("rust_add1", Linkage::Import, &sig).unwrap();
let callee = self.module.declare_function("rust_add2", Linkage::Import, &sig).unwrap();
let local_callee = self.module.declare_func_in_func(callee, bcx.func);
let call = bcx.ins().call(local_callee, &[add, add]);
bcx.inst_results(call)[0]
};
bcx.ins().return_(&[cr]);
//let sh = bcx.ins().sshr_imm(param, 3);
//bcx.ins().return_(&[sh]);
bcx.seal_all_blocks();
bcx.finalize();
}
self.module.define_function(func_a, &mut self.ctx).unwrap();
self.module.clear_context(&mut self.ctx);
//module.finalize_definitions().unwrap(); can be done multiple times
self.ctx.func.signature = sig_b;
self.ctx.func.name = UserFuncName::user(0, func_b.as_u32());
{
let mut bcx: FunctionBuilder = FunctionBuilder::new(&mut self.ctx.func, &mut self.func_ctx);
let block = bcx.create_block();
bcx.switch_to_block(block);
bcx.append_block_params_for_function_params(block);
let arg = bcx.block_params(block)[0];
let local_func = self.module.declare_func_in_func(func_a, &mut bcx.func);
//let arg = bcx.ins().iconst(self.int, 30 << 3);
/*
bcx.ins().return_call(local_func, &[arg]);
*/
let call = bcx.ins().call(local_func, &[arg]);
let value = {
let results = bcx.inst_results(call);
assert_eq!(results.len(), 1);
results[0].clone()
};
bcx.ins().return_(&[value]);
bcx.seal_all_blocks();
bcx.finalize();
}
self.module.define_function(func_b, &mut self.ctx).unwrap();
self.module.clear_context(&mut self.ctx);
// perform linking
self.module.finalize_definitions().unwrap();
//let code_a = self.module.get_finalized_function(func_a);
//let ptr_a = unsafe { mem::transmute::<_, extern "C" fn (Form) -> Form>(code_a) };
let code_b = self.module.get_finalized_function(func_b);
let ptr_b = unsafe { mem::transmute::<_, extern "C" fn (Form) -> Form>(code_b) };
(func_a, ptr_b)
}
}
#[repr(C)]
pub struct Cvec<T> {
ptr: NonNull<T>,
cap: usize,
len: usize,
}
unsafe impl<T: Send> Send for Cvec<T> {}
unsafe impl<T: Sync> Sync for Cvec<T> {}
impl<T> Cvec<T> {
pub fn new() -> Self {
assert!(mem::size_of::<T>() != 0, "no ZST");
Cvec {
ptr: NonNull::dangling(),
len: 0,
cap: 0,
}
}
fn grow(&mut self) {
let (new_cap, new_layout) = if self.cap == 0 {
(1, Layout::array::<T>(1).unwrap())
} else {
let new_cap = 2 * self.cap;
let new_layout = Layout::array::<T>(new_cap).unwrap();
(new_cap, new_layout)
};
assert!(new_layout.size() <= isize::MAX as usize, "allocation too large");
let new_ptr = if self.cap == 0 {
unsafe { alloc::alloc(new_layout) }
} else {
let old_layout = Layout::array::<T>(self.cap).unwrap();
let old_ptr = self.ptr.as_ptr() as *mut u8;
unsafe { alloc::realloc(old_ptr, old_layout, new_layout.size()) }
};
self.ptr = match NonNull::new(new_ptr as *mut T) {
Some(p) => p,
None => alloc::handle_alloc_error(new_layout),
};
self.cap = new_cap;
}
pub fn push(&mut self, elem: T) {
if self.len == self.cap { self.grow(); }
unsafe {
ptr::write(self.ptr.as_ptr().add(self.len), elem);
}
self.len += 1;
}
pub fn pop(&mut self) -> Option<T> {
if self.len == 0 {
None
} else {
self.len -= 1;
unsafe {
Some(ptr::read(self.ptr.as_ptr().add(self.len)))
}
}
}
}
impl<T> Drop for Cvec<T> {
fn drop(&mut self) {
if self.cap != 0 {
while let Some(_) = self.pop() {}
let layout = Layout::array::<T>(self.cap).unwrap();
unsafe {
alloc::dealloc(self.ptr.as_ptr() as *mut u8, layout);
}
}
}
}
impl<T> Deref for Cvec<T> {
type Target = [T];
fn deref(&self) -> &[T] {
unsafe {
std::slice::from_raw_parts(self.ptr.as_ptr(), self.len)
}
}
}
impl<T> DerefMut for Cvec<T> {
fn deref_mut(&mut self) -> &mut [T] {
unsafe {
std::slice::from_raw_parts_mut(self.ptr.as_ptr(), self.len)
}
}
}
impl<T: Clone> Clone for Cvec<T> {
fn clone(&self) -> Cvec<T> {
let layout = Layout::array::<T>(self.cap).unwrap();
let ptr = match NonNull::new(unsafe { alloc::alloc(layout) } as *mut T) {
Some(p) => p,
None => alloc::handle_alloc_error(layout),
};
for i in 0..self.len {
unsafe { ptr::write(ptr.as_ptr().add(i), self[i].clone()); }
}
Self { ptr, cap: self.cap, len: self.len }
}
}
impl<T: PartialEq> PartialEq for Cvec<T> {
fn eq(&self, other: &Self) -> bool {
self.deref() == other.deref()
}
}
impl<T: Eq> Eq for Cvec<T> {}
// insert, remove, into_iter, and drain all missing
impl<T: fmt::Display> fmt::Display for Cvec<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "[")?;
for x in self.iter() {
write!(f, " {}", x)?;
}
write!(f, " ]")?;
Ok(())
}
}
impl<T: fmt::Debug> fmt::Debug for Cvec<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "[")?;
for x in self.iter() {
write!(f, " {:?}", x)?;
}
write!(f, " ]")?;
Ok(())
}
}
#[repr(C)]
pub struct Crc<T> {
ptr: NonNull<CrcInner<T>>,
phantom: PhantomData<CrcInner<T>>
}
#[repr(C)]
pub struct CrcInner<T> {
rc: Cell<usize>,
data: T,
}
impl<T> CrcInner<T> {
pub unsafe fn increment(&self) {
let old = self.rc.get();
self.rc.set(old + 1);
if old > isize::MAX as usize {
std::process::abort();
}
}
}
impl<T> Crc<T> {
pub fn new(data: T) -> Crc<T> {
let boxed = Box::new(CrcInner { rc: Cell::new(1), data });
Crc {
ptr: NonNull::new(Box::into_raw(boxed)).unwrap(),
phantom: PhantomData,
}
}
pub fn into_ptr(self) -> *mut CrcInner<T> {
ManuallyDrop::new(self).ptr.as_ptr() as *mut CrcInner<T>
}
pub fn from_ptr(ptr: *mut CrcInner<T>) -> Self {
Crc {
ptr: NonNull::new(ptr).unwrap(),
phantom: PhantomData,
}
}
}
unsafe impl<T: Sync+Send> Send for Crc<T> {}
unsafe impl<T: Sync+Send> Sync for Crc<T> {}
impl<T> Deref for Crc<T> {
type Target = T;
fn deref(&self) -> &T {
let inner = unsafe { self.ptr.as_ref() };
&inner.data
}
}
impl<T: fmt::Debug> fmt::Debug for Crc<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "{:?}", self.deref())
}
}
impl<T> Clone for Crc<T> {
fn clone(&self) -> Crc<T> {
unsafe { self.ptr.as_ref().increment(); }
Self {
ptr: self.ptr,
phantom: PhantomData,
}
}
}
impl<T> Drop for Crc<T> {
fn drop(&mut self) {
let inner = unsafe { self.ptr.as_mut() };
let old = inner.rc.get();
inner.rc.set(old - 1);
if old != 1 {
return;
}
unsafe { drop(Box::from_raw(self.ptr.as_ptr())); }
}
}
#[derive(Debug, Eq, PartialEq, Ord, PartialOrd, Clone, Copy)]
#[repr(transparent)]
pub struct ID {
pub id: i64
}
impl fmt::Display for ID {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "{}", self.id)
}
}
#[repr(C)]
pub struct Closure {
params: Cvec<String>,
e: Form,
body: Form,
id: ID,
}
#[repr(C)]
pub struct Form {
data: *const Form,
phantom: PhantomData<Form>
}
#[repr(C)]
struct FormPair {
car: Form,
cdr: Form,
}
#[derive(Debug, Eq, PartialEq, Clone, Copy)]
#[repr(usize)]
pub enum Prim {
Add,
Sub,
Mul,
Div,
Mod,
Eq,
Cons,
Car,
Cdr,
}
impl Prim {
fn two_params(self) -> bool {
match self {
Prim::Car | Prim::Cdr => false,
_ => true,
}
}
}
/*
* this better be a 64 bit platform
* huh, if we only support i32s, then we have a lot more room for tags
* 8 byte alignment gets us 3 bits, or uh 8 options
* we'll choose 000 for ints to make math easy
*
* 000 - Int
* 001 - Nil
* 010 - Bool(false) // this is needlessly wasteful of the bits but hay - should take one of them over as a String probs
* 011 - Bool(true)
* 100 - Symbol - will want to convert into an Crc around a StringRawParts struct
* 101 - Pair - an Crc around a Pair struct
* 110 - Closure- eek: Closure(Cvec<String>, Crc<Form>, Crc<Form>, ID),
* xxxx 111 - Prim (xxxx for which one)
*
* I don't actually think we need our own repr(C) Cvec implementation, at least not for now - we can
* make do with a CvecRawParts struct (without implementations)
* Hay I did it anyway
*
* in both cases, StringRawParts and CvecRawParts, we can rebuild slices from the raw parts for
* read-only access, which is all we need (until Drop, at which point we should re-constitute them
* from their raw parts, which is stable)
*
* For symbols, it would actually make sense to create the String, then leak it so it lasts for the
* program, then deduplicate to it and pass the static const slice around
* Could even fit entirely in the Form if the max length of a symbol is 2^16
*/
const TAG_OFFSET: usize = 3;
const SYM_LEN_OFFSET: usize = 3;
const SYM_LEN_MASK: usize = 0xFF; // could be bigger
const SYM_PTR_OFFSET: usize = 11;
const TAG_MASK: usize = 0b111;
const TAG_INT: usize = 0b000;
const TAG_NIL: usize = 0b001;
const TAG_BOOL_FALSE: usize = 0b010;
const TAG_BOOL_TRUE: usize = 0b011;
const TAG_SYMBOL: usize = 0b100;
const TAG_PAIR: usize = 0b101;
const TAG_CLOSURE: usize = 0b110;
const TAG_PRIM: usize = 0b111;
static SYMBOLS: Lazy<Mutex<BTreeMap<String,&'static str>>> = Lazy::new(Mutex::default);
impl Form {
pub fn new_int(x: isize) -> Self {
Self { data: (x << TAG_OFFSET) as *const Form, phantom: PhantomData }
}
pub fn new_nil() -> Self {
Self { data: TAG_NIL as *const Form, phantom: PhantomData }
}
pub fn new_bool(b: bool) -> Self {
Self { data: (if b { TAG_BOOL_TRUE } else { TAG_BOOL_FALSE }) as *const Form, phantom: PhantomData }
}
pub fn new_pair(car: Form, cdr: Form) -> Self {
let p = Crc::new(FormPair { car, cdr }).into_ptr() as usize;
assert!(p & TAG_MASK == 0);
Self { data: (p | TAG_PAIR) as *const Form, phantom: PhantomData }
}
fn new_closure(params: Cvec<String>, e: Form, body: Form, ctx: &mut Ctx) -> Self {
let p = Crc::new(Closure { params, e, body, id: ctx.alloc_id() }).into_ptr() as usize;
assert!(p & TAG_MASK == 0);
Self { data: (p | TAG_CLOSURE) as *const Form, phantom: PhantomData }
}
pub fn new_prim(p: Prim) -> Self {
Self { data: (((p as usize) << TAG_OFFSET) | TAG_PRIM) as *const Form, phantom: PhantomData }
}
pub fn new_symbol(s: &str) -> Form {
assert!(s.len() < SYM_LEN_MASK);
let mut symbols = SYMBOLS.lock().unwrap();
let ds = if let Some(ds) = symbols.get(s) {
ds
} else {
// here we leak the memory of a new owned copy of s,
// and then transmute it into an &'static str that we keep in our global
// map for deduplication. Spicy stuff.
let mut value = ManuallyDrop::new(s.to_owned());
value.shrink_to_fit();
let slice = unsafe { std::mem::transmute(value.as_str()) };
symbols.insert(s.to_owned(), slice);
slice
};
//println!("Deduped {s} to {ds}");
Self { data: (((ds.as_ptr() as usize) << SYM_PTR_OFFSET) | (ds.len() << SYM_LEN_OFFSET) | TAG_SYMBOL) as *const Form, phantom: PhantomData }
}
pub fn int(&self) -> Result<isize> {
if self.data as usize & TAG_MASK == TAG_INT {
Ok(self.data as isize >> 3)
} else {
Err(anyhow!("car on not a pair"))
}
}
pub fn car(&self) -> Result<&Form> {
if self.data as usize & TAG_MASK == TAG_PAIR {
Ok(unsafe { &(*((self.data as usize & !TAG_MASK) as *mut CrcInner<FormPair>)).data.car })
} else {
Err(anyhow!("car on not a pair"))
}
}
pub fn cdr(&self) -> Result<&Form> {
if self.data as usize & TAG_MASK == TAG_PAIR {
Ok(unsafe { &(*((self.data as usize & !TAG_MASK) as *mut CrcInner<FormPair>)).data.cdr })
} else {
Err(anyhow!("cdr on not a pair"))
}
}
pub fn closure(&self) -> Result<&Closure> {
if self.data as usize & TAG_MASK == TAG_CLOSURE {
Ok(unsafe { &(*((self.data as usize & !TAG_MASK) as *mut CrcInner<Closure>)).data })
} else {
Err(anyhow!("closure on on not a closure"))
}
}
pub fn prim(&self) -> Result<Prim> {
if self.data as usize & TAG_MASK == TAG_PRIM {
Ok(unsafe { *(&((self.data as usize) >> TAG_OFFSET) as *const usize as *const Prim) })
} else {
Err(anyhow!("prim on on not a prim"))
}
}
pub fn sym(&self) -> Result<&str> {
if self.data as usize & TAG_MASK == TAG_SYMBOL {
let len = ((self.data as usize) >> SYM_LEN_OFFSET) & SYM_LEN_MASK;
let ptr = ((self.data as usize) >> SYM_PTR_OFFSET) as *const u8;
Ok(std::str::from_utf8(unsafe { std::slice::from_raw_parts(ptr, len) }).unwrap())
} else {
Err(anyhow!("sym on on not a str"))
}
}
fn truthy(&self) -> bool {
match self.data as usize & TAG_MASK {
TAG_NIL => false,
TAG_BOOL_FALSE => false,
TAG_BOOL_TRUE => true,
_ => true,
}
}
fn bool(&self) -> Result<bool> {
match self.data as usize & TAG_MASK {
TAG_BOOL_FALSE => Ok(false),
TAG_BOOL_TRUE => Ok(true),
_ => Err(anyhow!("bool on not a bool")),
}
}
fn pair(&self) -> Result<(&Form,&Form)> {
if self.data as usize & TAG_MASK == TAG_PAIR {
let crc_ptr = (self.data as usize & !TAG_MASK) as *mut CrcInner<FormPair>;
Ok(unsafe { (&(*crc_ptr).data.car,&(*crc_ptr).data.cdr) })
} else {
Err(anyhow!("pair on not a pair"))
}
}
fn is_nil(&self) -> bool {
match self.data as usize & TAG_MASK {
TAG_NIL => true,
_ => false,
}
}
pub fn define(&self, s: &str, v: Form) -> Form {
Form::new_pair(Form::new_pair(Form::new_symbol(s), v), self.clone())
}
pub fn append(&self, x: Form) -> Result<Form> {
match self.data as usize & TAG_MASK {
TAG_PAIR => self.cdr().unwrap().append(x).map(|x| Form::new_pair(self.car().unwrap().clone(), x)),
TAG_NIL => Ok(Form::new_pair(x, Form::new_nil())),
_ => Err(anyhow!("append to not a pair")),
}
}
pub fn root_env() -> Form {
let mut e = Form::new_nil();
for (s, v) in [
("+", Form::new_prim(Prim::Add)),
("-", Form::new_prim(Prim::Sub)),
("*", Form::new_prim(Prim::Mul)),
("/", Form::new_prim(Prim::Div)),
("%", Form::new_prim(Prim::Mod)),
("cons", Form::new_prim(Prim::Cons)),
("cdr", Form::new_prim(Prim::Cdr)),
("car", Form::new_prim(Prim::Car)),
("=", Form::new_prim(Prim::Eq)),
("nil", Form::new_nil()),
] {
e = e.define(s, v);
}
e
}
pub fn lookup(&self, s: &str) -> Result<&Form> {
let mut e = self;
loop {
let (kv, ne) = e.pair()?;
let (sp, v) = kv.pair()?;
if sp.sym()? == s {
return Ok(v);
}
e = ne;
}
}
}
impl Drop for Form {
fn drop(&mut self) {
match self.data as usize & TAG_MASK {
TAG_INT | TAG_NIL | TAG_BOOL_FALSE | TAG_BOOL_TRUE | TAG_PRIM | TAG_SYMBOL => { /*println!("dropping simple {self}"); */ }, // doing nothing for symbol is fine
// since it's deduplicated
TAG_PAIR => {
let _ = Crc::<FormPair>::from_ptr( (self.data as usize & !TAG_MASK) as *mut CrcInner<FormPair> );
},
TAG_CLOSURE => {
let _ = Crc::<Closure>::from_ptr( (self.data as usize & !TAG_MASK) as *mut CrcInner<Closure> );
},
_ => unreachable!(),
}
}
}
impl Clone for Form {
fn clone(&self) -> Self {
match self.data as usize & TAG_MASK {
TAG_INT | TAG_NIL | TAG_BOOL_FALSE | TAG_BOOL_TRUE | TAG_PRIM | TAG_SYMBOL => { Self { data: self.data, phantom: PhantomData } },
TAG_PAIR => {
unsafe { (*((self.data as usize & !TAG_MASK) as *mut CrcInner<FormPair>)).increment(); }
Self { data: self.data, phantom: PhantomData }
},
TAG_CLOSURE => {
unsafe { (*((self.data as usize & !TAG_MASK) as *mut CrcInner<Closure>)).increment(); }
Self { data: self.data, phantom: PhantomData }
},
_ => unreachable!(),
}
}
}
impl PartialEq for Form {
fn eq(&self, other: &Self) -> bool {
match self.data as usize & TAG_MASK {
TAG_INT | TAG_NIL | TAG_BOOL_FALSE | TAG_BOOL_TRUE | TAG_PRIM | TAG_SYMBOL => { self.data == other.data },
TAG_PAIR => {
if other.data as usize & TAG_MASK != TAG_PAIR {
return false;
}
self.car().unwrap() == other.car().unwrap() && self.cdr().unwrap() == other.cdr().unwrap()
},
TAG_CLOSURE => {
if other.data as usize & TAG_MASK != TAG_CLOSURE {
return false;
}
let Closure { params, e, body, id, } = self.closure().unwrap();
let Closure { params: oparams, e: oe, body: obody, id: oid, } = self.closure().unwrap();
params == oparams && e == oe && body == obody && id == oid
},
_ => unreachable!(),
}
}
}
impl Eq for Form {}
impl fmt::Display for Form {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self.data as usize & TAG_MASK {
TAG_INT => {
write!(f, "{}", self.data as isize >> 3)?;
},
TAG_NIL => {
write!(f, "nil")?;
},
TAG_BOOL_FALSE => {
write!(f, "false")?;
},
TAG_BOOL_TRUE => {
write!(f, "true")?;
},
TAG_PAIR => {
write!(f, "({}", self.car().unwrap())?;
let mut traverse = self.cdr().unwrap();
loop {
match traverse.data as usize & TAG_MASK {
TAG_PAIR => {
write!(f, " {}", traverse.car().unwrap())?;
traverse = traverse.cdr().unwrap();
},
TAG_NIL => {
write!(f, ")")?;
return Ok(());
},
_ => {
write!(f, ". {traverse})")?;
return Ok(());
}
}
}
},
TAG_PRIM => {
write!(f, "{:?}", self.prim().unwrap())?;
},
TAG_SYMBOL => {
write!(f, "'{}", self.sym().unwrap())?;
},
TAG_CLOSURE => {
let Closure { params, e, body, id, } = self.closure().unwrap();
write!(f, "<{params} {e} {body} {id}>")?;
},
_ => unreachable!(),
}
Ok(())
}
}
impl fmt::Debug for Form {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "Form({self})")
}
}
impl From<String> for Form { fn from(item: String) -> Self { Form::new_symbol(&item) } }
impl From<&str> for Form { fn from(item: &str) -> Self { Form::new_symbol(item) } }
impl From<isize> for Form { fn from(item: isize) -> Self { Form::new_int(item) } }
impl From<bool> for Form { fn from(item: bool) -> Self { Form::new_bool(item) } }
impl<A: Into<Form>, B: Into<Form>> From<(A, B)> for Form {
fn from(item: (A, B)) -> Self {
Form::new_pair(item.0.into(), item.1.into())
}
}
// This first Simple Lisp really is
//
// No fexprs, no mutation, no continuations, no macros, no strings.
// Int/Bool/Nil/Pair/Symbol/Closure/Prim.
//
// Figuring out GC between a JIT and Rust will be tricky.
// Can start with a like tracing-JIT-into-bytecode
// let's make our own Box, Crc, maybe Arc, Vec too?
// rustonomicon
fn eval_prim(f: Prim, b: Form, a: Option<Form>) -> Result<Form> {
Ok(match f {
Prim::Car => b.car()?.clone(),
Prim::Cdr => b.cdr()?.clone(),
_ => {
let a = a.unwrap();
match f {
Prim::Add => Form::new_int(a.int()? + b.int()?),
Prim::Sub => Form::new_int(a.int()? - b.int()?),
Prim::Mul => Form::new_int(a.int()? * b.int()?),
Prim::Div => Form::new_int(a.int()? / b.int()?),
Prim::Mod => Form::new_int(a.int()? % b.int()?),
Prim::Cons => Form::new_pair(a, b),
Prim::Eq => Form::new_bool(a == b),
_ => unreachable!(),
}
}
})
}
// JIT Decisions
// JIT Closure vs JIT Closure-Template
// That is, do you treat the closed-over variables as constant
// currently we do! if a lookup is not to one of our in-func defined variables, it's a
// constant. done in trace_lookup
// Or maybe more specifically, which closed over variables do you treat as constant
// This will later inform optimistic inlining of primitives, I imagine
// Inline or not
// Rejoin branches or not
// currently we trace into extended basic blocks, in the future stitch those together + const
// prop to do more standard traces (after longer warm-up)
//
// currently we basically just have lazy EBB bytecode construction
// which I like!
#[derive(Debug)]
enum Op {
Guard { const_value: Form, side_val: Option<Form>, side_cont: Crc<Cont>, side_id: ID, tbk: TraceBookkeeping },
Debug,
Define { sym: String },
Const (Form),
Drop,
Lookup { sym: String },
Call { len: usize, statik: Option<ID>, nc: Crc<Cont>, nc_id: ID },
InlinePrim(Prim),
Tail(usize,Option<ID>),
Return,
}
impl fmt::Display for Op {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Op::Guard { const_value, side_val:_, side_cont:_, side_id, tbk:_ } => write!(f, "Guard{side_id}({const_value})"),
Op::Debug => write!(f, "Debug"),
Op::Define { sym } => write!(f, "Define({sym})"),
Op::Const ( con ) => write!(f, "Const_{con}"),
Op::Drop => write!(f, "Drop"),
Op::Lookup { sym } => write!(f, "Lookup({sym})"),
Op::Call { len, nc:_, nc_id, statik } => write!(f, "Call{nc_id}({len},{statik:?})"),
Op::InlinePrim(prim) => write!(f, "{prim:?}"),
Op::Tail(len,oid) => write!(f, "Tail({len},{oid:?})"),
Op::Return => write!(f, "Return"),
}
}
}
impl Op {
fn cnst(&self) -> Result<Form> {
match self {
Op::Const(c) => Ok(c.clone()),
_ => Err(anyhow!("const on not a const")),
}
}
}
#[derive(Debug,Clone)]
struct TraceBookkeeping {
func_id: ID,
stack_const: Vec<bool>,
defined_names: BTreeSet<String>,
}
#[derive(Clone,Debug)]
enum Cont {
MetaRet,
Ret { id: ID, },
Eval { c: Crc<Cont> },
Prim { s: &'static str, to_go: Form, c: Crc<Cont> },
Call { n: usize, to_go: Form, c: Crc<Cont> },
Frame { syms: Cvec<String>, id: ID, c: Crc<Cont> },
}
impl Cont {
fn is_ret(&self) -> bool {
match self {
Cont::Ret { id: _ } => true,
_ => false,
}
}
}
#[derive(Debug)]
struct Trace {
id: ID,
ops: Vec<Op>,
tbk: TraceBookkeeping,
}
impl Trace {
fn new(id: ID, func_id: ID) -> Self {
Trace { id, ops: vec![], tbk: TraceBookkeeping { stack_const: vec![], defined_names: BTreeSet::new(), func_id } }
}
fn follow_on(id: ID, tbk: TraceBookkeeping) -> Self {
Trace { id, ops: vec![], tbk }
}
}
impl fmt::Display for Trace {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "Trace for {} (func {}) [", self.id, self.tbk.func_id)?;
for op in &self.ops {
write!(f, " {}", op)?;
}
write!(f, " ]")?;
if !self.tbk.stack_const.is_empty() {
write!(f, "[")?;
for s in &self.tbk.stack_const {
write!(f, " {}", s)?;
}
write!(f, " ]")?;
}
Ok(())
}
}
#[derive(Debug)]
struct Ctx {
id_counter: i64,
cont_count: BTreeMap<ID, i64>,
tracing: Option<Trace>,
traces: BTreeMap<ID, Vec<Op>>,
trace_resume_data: BTreeMap<ID, TraceBookkeeping>,
}
impl fmt::Display for Ctx {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "Ctx")
}
}
impl Ctx {
fn new() -> Ctx {
Ctx {
id_counter: 0,
cont_count: BTreeMap::new(),
tracing: None,
traces: BTreeMap::new(),
trace_resume_data: BTreeMap::new(),
}
}
fn alloc_id(&mut self) -> ID {
self.id_counter += 1;
ID { id: self.id_counter }
}
fn trace_running(&self) -> bool { self.tracing.is_some() }
// Though I guess that means call start should recieve the parameters
// also, for like variables, it should guard on what function
// if dynamic, interacts with the constant tracking
// 8 options
// - not tracing, closure - do stats
// - not tracing, prim - do nothing
// - tracing, Static Prim - inline prim
// - tracing, Static non-self - inline call? (currently static call)
// - tracing, Static, tail-self - emit tail (static) (we removed loop because it's a static jump back to the head trace regardless)
// - tracing, Static,nontail-self- emit call (static)
// - tracing, Dynamic, tail - emit tail
// - tracing, Dynamic, non-tail - emit call
fn trace_call(&mut self, call_len: usize, tmp_stack: &Cvec<Form>, nc: &Crc<Cont>) -> Option<ID> {
// Needs to take and use parameters for mid-trace
// needs to guard on function called if non-constant
println!("trace_call call_len={call_len},trace={:?}, tmp_stack {tmp_stack:?}", self.tracing);
if let Some(trace) = &mut self.tracing {
let statik = if trace.tbk.stack_const[trace.tbk.stack_const.len()-call_len] {
// const - TODO: for now, we don't inline but we will want to later (based on what
// metrics? can we run them simultaniously, heirarchially? with our new approach on
// prims maybe (heck we may need to go farther, and remove the InlinePrim!)
let func = &tmp_stack[tmp_stack.len()-call_len];
match func.data as usize & TAG_MASK {
TAG_PRIM => {
let p = func.prim().unwrap();
if (&trace.tbk.stack_const[trace.tbk.stack_const.len()-call_len..]).iter().all(|x| *x) {
trace.tbk.stack_const.truncate(trace.tbk.stack_const.len()-call_len);
let b = trace.ops[trace.ops.len()-1].cnst().unwrap();
let (a,f) = if call_len == 3 {
(Some(trace.ops[trace.ops.len()-2].cnst().unwrap()), p)
} else { (None, p) };
for _ in 0..call_len {
trace.ops.push(Op::Drop);
}
trace.ops.push(Op::Const(eval_prim(f, b, a).unwrap()));
trace.tbk.stack_const.push(true);
} else {
trace.tbk.stack_const.truncate(trace.tbk.stack_const.len()-call_len);
trace.ops.push(Op::InlinePrim(p));
trace.tbk.stack_const.push(false);
}
return None;
},
TAG_CLOSURE => {
let Closure { id, .. } = func.closure().unwrap();
if nc.is_ret() {
if *id == trace.tbk.func_id {
// we removed the loop opcode because this trace needs to know the
// func header trace id anyway
trace.ops.push(Op::Tail(call_len, Some(*id)));
} else {
// should be inline
trace.ops.push(Op::Tail(call_len, Some(*id)));
}
println!("Ending trace at loop/tail recursive call!");
println!("\t{}", trace);
self.traces.insert(trace.id, self.tracing.take().unwrap().ops);
return None;
}
// fall through to be a static call, though also would normally be inline
Some(*id)
},
b => panic!("bad func {b:?}"),
}
} else { None };
// (normally not const) or has tmps - Call or TailCall
if nc.is_ret() {
trace.ops.push(Op::Tail(call_len,statik));
println!("Ending trace at tail recursive call!");
println!("\t{}", trace);
self.traces.insert(trace.id, self.tracing.take().unwrap().ops);
return None;
} else {
trace.tbk.stack_const.truncate(trace.tbk.stack_const.len()-call_len);
self.id_counter += 1; let nc_id = ID { id: self.id_counter }; // HACK - I can't use the method cuz trace is borrowed
trace.ops.push(Op::Call { len: call_len, statik, nc: Crc::clone(nc), nc_id });
println!("Ending trace at call!");
println!("\t{}", trace);
self.trace_resume_data.insert(nc_id, trace.tbk.clone());
self.traces.insert(trace.id, self.tracing.take().unwrap().ops);
return Some(nc_id);
}
}
None
}
fn trace_frame(&mut self, syms: &Cvec<String>, id: ID) {
let inline = self.tracing.is_some();
let entry = self.cont_count.entry(id).or_insert(0);
println!("tracing call start for {id}, has been called {} times so far", *entry);
*entry += 1;
if *entry > 1 && self.tracing.is_none() && self.traces.get(&id).is_none() {
self.tracing = Some(Trace::new(id, id));
}
for s in syms.iter().rev() {
self.trace_define(s, inline);
}
self.trace_drop(inline);
}
fn trace_define(&mut self, sym: &str, pop: bool) {
if let Some(trace) = &mut self.tracing {
trace.ops.push(Op::Define { sym: sym.to_owned() });
trace.tbk.defined_names.insert(sym.to_owned());
if pop {
trace.tbk.stack_const.pop().unwrap();
}
}
}
fn trace_drop(&mut self, pop: bool) {
if let Some(trace) = &mut self.tracing {
trace.ops.push(Op::Drop);
if pop {
trace.tbk.stack_const.pop().unwrap();
}
}
}
fn trace_call_end(&mut self, id: ID, follow_on_trace_data: Option<ID>) {
println!("tracing call end for {id} followon {follow_on_trace_data:?}");
if let Some(trace) = &mut self.tracing {
if trace.tbk.func_id == id {
trace.ops.push(Op::Return);
println!("Ending trace at end of call!");
println!("\t{}", trace);
self.traces.insert(trace.id, self.tracing.take().unwrap().ops);
}
}
if self.tracing.is_none() {
self.try_resume_trace(follow_on_trace_data);
}
}
fn try_resume_trace(&mut self, follow_on_trace_data: Option<ID>) {
if let Some(follow_id) = follow_on_trace_data {
println!("looking follow-on trace {follow_id} in {:?}", self.trace_resume_data);
if let Some(follow_tbk) = self.trace_resume_data.remove(&follow_id) {
println!("starting follow-on trace {follow_id}, {follow_tbk:?}");
let mut trace = Trace::follow_on(follow_id,follow_tbk);
trace.tbk.stack_const.push(false); // fix with actual, if this ends up being a
// static call with static param list that isn't
// inlined for whatever reason...
self.tracing = Some(trace);
}
}
}
fn trace_guard<T: Into<Form> + std::fmt::Debug>(&mut self, value: T, other: impl Fn()->(Option<Form>,Crc<Cont>)) {
println!("Tracing guard {value:?}");
if let Some(trace) = &mut self.tracing {
let (side_val, side_cont) = other();
self.id_counter += 1; let side_id = ID { id: self.id_counter }; // HACK - I can't use the method cuz trace is borrowed
trace.ops.push(Op::Guard { const_value: value.into(), side_val, side_cont, side_id, tbk: trace.tbk.clone() });
}
}
fn trace_debug(&mut self) {
if let Some(trace) = &mut self.tracing {
trace.ops.push(Op::Debug);
}
}
fn trace_lookup(&mut self, s: &str, f: &Form) {
if let Some(trace) = &mut self.tracing {
// constant depends on which env, and I think this is the only spot that cares for
// closure jit vs lambda jit
if trace.tbk.defined_names.contains(s) {
trace.ops.push(Op::Lookup { sym: s.to_owned() });
trace.tbk.stack_const.push(false);
} else {
trace.ops.push(Op::Const(f.clone()));
trace.tbk.stack_const.push(true);
}
}
}
fn trace_constant(&mut self, c: &Form) {
if let Some(trace) = &mut self.tracing {
trace.ops.push(Op::Const(c.clone()));
trace.tbk.stack_const.push(true);
}
}
fn trace_lambda(&mut self, _params: &[String], _e: &Form, _body: &Form) {
if let Some(_trace) = &mut self.tracing {
// TODO
// kinda both also
unimplemented!("trace lambda");
}
}
// returns f, e, c for interp
fn execute_trace_if_exists(&mut self,
id: ID,
e: &Form,
tmp_stack: &mut Cvec<Form>,
ret_stack: &mut Cvec<(Form, Crc<Cont>, Option<ID>)>) -> Result<Option<(Form, Form, Cont)>> {
if self.trace_running() {
println!("Not playing back trace because recording trace");
return Ok(None); // can't trace while running a trace for now (we don't inline now anyway),
// in the future it should just tack on the opcodes while jugging the proper
// bookkeeping stacks
}
if let Some(mut trace) = self.traces.get(&id) {
println!("Starting trace playback");
let mut e = e.clone();
loop {
println!("Running trace {trace:?}, \n\ttmp_stack:{tmp_stack:?}");
for b in trace.iter() {
match b {
Op::Guard { const_value, side_val, side_cont, side_id, tbk } => {
println!("Guard(op) {const_value}");
if const_value != tmp_stack.last().unwrap() {
if let Some(new_trace) = self.traces.get(side_id) {
if side_val.is_some() {
tmp_stack.pop().unwrap();
}
println!("\tchaining trace to side trace");
trace = new_trace;
break; // break out of this trace and let infinate loop spin
} else {
println!("\tending playback b/c failed guard");
assert!(self.tracing.is_none());
let mut ntrace = Trace::follow_on(*side_id,tbk.clone());
if let Some(side_val) = side_val {
*tmp_stack.last_mut().unwrap() = side_val.clone();
*ntrace.tbk.stack_const.last_mut().unwrap() = false; // this might be able to be
// more precise, actually
}
self.tracing = Some(ntrace);
return Ok(Some((tmp_stack.pop().unwrap(), e, (**side_cont).clone())));
}
}
}
Op::Debug => {
println!("Debug(op) {}", tmp_stack.last().unwrap());
}
Op::Define { sym } => {
let v = tmp_stack.pop().unwrap();
println!("Define(op) {sym} = {}", v);
e = e.define(sym, v);
}
Op::Const ( con ) => {
println!("Const(op) {con}");
tmp_stack.push(con.clone());
}
Op::Drop => {
println!("Drop(op) {}", tmp_stack.last().unwrap());
tmp_stack.pop().unwrap();
}
Op::Lookup { sym } => {
println!("Lookup(op) {sym}");
tmp_stack.push(e.lookup(sym)?.clone());
}
Op::InlinePrim(prim) => {
println!("InlinePrim(op) {prim:?}");
let b = tmp_stack.pop().unwrap();
let a = if prim.two_params() { Some(tmp_stack.pop().unwrap()) } else { None };
tmp_stack.pop().unwrap(); // pop the prim
tmp_stack.push(eval_prim(*prim, b, a)?);
}
Op::Call { len, nc, nc_id, statik } => {
println!("Call(op)");
if let Some(static_call_id) = statik {
if let Some(new_trace) = self.traces.get(static_call_id) {
ret_stack.push((e.clone(), (*nc).clone(), Some(*nc_id)));
println!("\tchaining to call trace b/c Call with statik");
trace = new_trace;
break; // break out of this trace and let infinate loop spin
}
}
let func = &tmp_stack[tmp_stack.len()-*len];
match func.data as usize & TAG_MASK {
TAG_PRIM => {
let p = func.prim().unwrap();
let b = tmp_stack.pop().unwrap();
let a = if *len == 2 { None } else { assert!(*len == 3); Some(tmp_stack.pop().unwrap()) };
let result = eval_prim(p, b, a)?;
if let Some(new_trace) = self.traces.get(nc_id) {
*tmp_stack.last_mut().unwrap() = result; // for the prim itself
println!("\tchaining to ret trace b/c Call with dyamic but primitive and next traced");
trace = new_trace;
break; // break out of this trace and let infinate loop spin
} else {
println!("\tstopping playback to ret b/c Call with dyamic but primitive and next not-traced");
tmp_stack.pop().unwrap(); // for the prim itself
return Ok(Some((result, e, (**nc).clone())));
}
},
TAG_CLOSURE => {
let Closure { params: ps, e: ie, body: b, id: call_id, } = func.closure().unwrap();
if ps.len() != *len-1 {
bail!("arguments length doesn't match");
}
ret_stack.push((e.clone(), (*nc).clone(), Some(*nc_id)));
if let Some(new_trace) = self.traces.get(call_id) {
println!("\tchaining to call trace b/c Call with dyamic but traced");
e = ie.clone();
trace = new_trace;
break; // break out of this trace and let infinate loop spin
} else {
return Ok(Some((b.clone(), ie.clone(), Cont::Frame { syms: ps.clone(), id: *call_id, c: Crc::new(Cont::Eval { c: Crc::new(Cont::Ret { id: *call_id }) }) })));
}
},
ncomb => {
println!("Current stack is {tmp_stack:?}");
bail!("tried to call a non-comb {ncomb}")
},
}
}
Op::Tail(_len,_oid) => {
println!("Tail(op)");
// Huh, this actually has to know how many envs we pushed on so we can pop
// them off
unimplemented!();
}
Op::Return => {
println!("Return(op)");
let (e, nc, resume_data) = ret_stack.pop().unwrap();
if let Some(resume_id) = resume_data {
if let Some(new_trace) = self.traces.get(&resume_id) {
println!("\tchaining to return trace b/c Return {resume_id} - {new_trace:?}");
trace = new_trace;
break; // break out of this trace and let infinate loop spin
}
}
println!("\tending playback b/c Return, attempting to resume trace");
self.try_resume_trace(resume_data);
return Ok(Some((tmp_stack.pop().unwrap(), e, (*nc).clone())));
}
}
}
}
} else {
Ok(None)
}
}
}
pub fn eval(f: Form) -> Result<Form> {
let mut ctx = Ctx::new();
let mut f = f;
let mut e = Form::root_env();
let mut c = Cont::Eval { c: Crc::new(Cont::MetaRet) };
let mut ret_stack: Cvec<(Form, Crc<Cont>, Option<ID>)> = Cvec::new();
let mut tmp_stack: Cvec<Form> = Cvec::new();
loop {
match c {
Cont::MetaRet => {
println!("Ctx was {ctx}");
assert!(!ctx.trace_running());
return Ok(f);
}
Cont::Prim { s, to_go, c: nc } => {
match s {
"if" => {
let thn = to_go.car()?;
let els = to_go.cdr()?.car()?;
if f.truthy() {
ctx.trace_guard(true, || (Some(els.clone()), Crc::new(Cont::Eval { c: Crc::clone(&nc) })));
ctx.trace_drop(true);
f = thn.clone();
} else {
ctx.trace_guard(false, ||(Some(thn.clone()), Crc::new(Cont::Eval { c: Crc::clone(&nc) })));
ctx.trace_drop(true);
f = els.clone();
}
c = Cont::Eval { c: nc };
},
"or" => {
let other = to_go.car()?;
if !f.truthy() {
ctx.trace_guard(false, || (None, nc.clone()));
ctx.trace_drop(true);
f = other.clone();
c = Cont::Eval { c: nc };
} else {
ctx.trace_guard(true, || (Some(other.clone()), Crc::new(Cont::Eval { c: Crc::clone(&nc) })));
c = (*nc).clone();
}
},
"and" => {
let other = to_go.car()?;
if f.truthy() {
ctx.trace_guard(true, || (None, nc.clone()));
ctx.trace_drop(true);
f = other.clone();
c = Cont::Eval { c: nc };
} else {
ctx.trace_guard(false, || (Some(other.clone()), Crc::new(Cont::Eval { c: Crc::clone(&nc) })));
c = (*nc).clone();
}
},
"begin" => {
if to_go.is_nil() {
c = (*nc).clone();
} else {
ctx.trace_drop(true);
f = to_go.car()?.clone();
c = Cont::Eval { c: Crc::new(Cont::Prim { s: "begin", to_go: to_go.cdr()?.clone(), c: nc }) };
}
},
"debug" => {
println!("Debug: {f}");
ctx.trace_debug();
c = (*nc).clone();
},
"define" => {
let sym = to_go.sym()?;
ctx.trace_define(&sym, true);
e = e.define(sym, f.clone());
c = (*nc).clone();
},
_ => {
panic!("bad prim {s}");
}
}
},
Cont::Ret { id, } => {
let (ne, nc, resume_data) = ret_stack.pop().unwrap();
ctx.trace_call_end(id, resume_data);
e = ne;
if let Some(nc_id) = resume_data {
tmp_stack.push(f); // ugly dance pt 1
if let Some((fp, ep, cp)) = ctx.execute_trace_if_exists(nc_id, &e, &mut tmp_stack, &mut ret_stack)? {
f = fp;
e = ep;
c = cp;
println!("After executing return trace, f={f}, tmp_stack is {tmp_stack:?}");
continue;
} else {
f = tmp_stack.pop().unwrap(); //ugly dance pt2
}
}
c = (*nc).clone();
},
Cont::Call { n, to_go, c: nc } => {
tmp_stack.push(f);
if to_go.is_nil() {
let resume_data = ctx.trace_call(n, &mut tmp_stack, &nc);
let func = tmp_stack[tmp_stack.len()-n].clone();
match func.data as usize & TAG_MASK {
TAG_PRIM => {
let p = func.prim().unwrap();
let b = tmp_stack.pop().unwrap();
let a = if n == 2 { None } else { assert!(n == 3); Some(tmp_stack.pop().unwrap()) };
f = eval_prim(p, b, a)?;
tmp_stack.pop().unwrap(); // for the prim itself
c = (*nc).clone();
},
TAG_CLOSURE => {
let Closure { params: ps, e: ie, body: b, id, } = func.closure().unwrap();
if ps.len() != n-1 {
bail!("arguments length doesn't match");
}
ret_stack.push((e.clone(), nc, resume_data));
if let Some((fp, ep, cp)) = ctx.execute_trace_if_exists(*id, ie, &mut tmp_stack, &mut ret_stack)? {
f = fp;
e = ep;
c = cp;
println!("After executing trace, f={f}, tmp_stack is {tmp_stack:?}");
} else {
println!("replacing {e} with {ie}");
e = ie.clone();
c = Cont::Frame { syms: ps.clone(), id: *id, c: Crc::new(Cont::Eval { c: Crc::new(Cont::Ret { id: *id }) }) };
f = b.clone();
}
},
ncomb => {
println!("Current stack is {tmp_stack:?}");
bail!("tried to call a non-comb {ncomb}")
},
}
} else {
f = to_go.car()?.clone();
c = Cont::Eval { c: Crc::new(Cont::Call { n: n+1, to_go: to_go.cdr()?.clone(), c: nc }) };
}
}
Cont::Frame { syms, id, c: nc } => {
ctx.trace_frame(&syms, id);
for s in syms.into_iter().rev() {
e = e.define(&s, tmp_stack.pop().unwrap());
}
tmp_stack.pop().unwrap(); // for the func value
c = (*nc).clone();
}
Cont::Eval { c: nc } => {
let tmp = f;
match tmp.data as usize & TAG_MASK {
TAG_SYMBOL => {
let s = tmp.sym().unwrap();
f = e.lookup(s)?.clone();
ctx.trace_lookup(s, &f);
c = (*nc).clone();
},
TAG_PAIR => {
let (car, cdr) = tmp.pair().unwrap();
match car.data as usize & TAG_MASK {
TAG_SYMBOL => {
let s = car.sym().unwrap();
match s {
"if" => {
f = cdr.car()?.clone();
c = Cont::Eval { c: Crc::new(Cont::Prim { s: "if", to_go: cdr.cdr()?.clone(), c: nc }) };
continue;
}
// and/or has to short-circut, so special form
// just like Scheme (bad ;) )
"or" => {
f = cdr.car()?.clone();
c = Cont::Eval { c: Crc::new(Cont::Prim { s: "or", to_go: cdr.cdr()?.clone(), c: nc }) };
continue;
}
"and" => {
f = cdr.car()?.clone();
c = Cont::Eval { c: Crc::new(Cont::Prim { s: "and", to_go: cdr.cdr()?.clone(), c: nc }) };
continue;
}
"begin" => {
f = cdr.car()?.clone();
c = Cont::Eval { c: Crc::new(Cont::Prim { s: "begin", to_go: cdr.cdr()?.clone(), c: nc }) };
continue;
}
"debug" => {
f = cdr.car()?.clone();
c = Cont::Eval { c: Crc::new(Cont::Prim { s: "debug", to_go: cdr.cdr()?.clone(), c: nc }) };
continue;
}
"define" => {
// note the swap, evaluating the second not the first (define a value..)
f = cdr.cdr()?.car()?.clone();
c = Cont::Eval { c: Crc::new(Cont::Prim { s: "define", to_go: cdr.car()?.clone(), c: nc }) };
continue;
}
"quote" => {
f = cdr.car()?.clone();
ctx.trace_constant(&f);
c = (*nc).clone();
continue;
}
// (lambda (a b) body)
"lambda" => {
let mut params_vec = Cvec::new();
let mut params = cdr.car()?;
while let Ok((ncar, ncdr)) = params.pair() {
params_vec.push(ncar.sym()?.to_string());
params = ncdr;
}
let body = cdr.cdr()?.car()?;
ctx.trace_lambda(&params_vec, &e, &body);
f = Form::new_closure(params_vec, e.clone(), body.clone(), &mut ctx);
c = (*nc).clone();
continue;
}
_ => { /* fallthrough */ }
}
}
_ => { /* fallthrough */ }
}
f = car.clone();
c = Cont::Eval { c: Crc::new(Cont::Call { n: 1, to_go: cdr.clone(), c: nc }) };
},
_ => {
// value, no eval
f = tmp;
ctx.trace_constant(&f);
c = (*nc).clone();
}
}
}
}
}
}