Rewritten assembler

Cargo.lock

@@ -35,6 +35,12 @@ version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3a8241f3ebb85c056b509d4327ad0358fbbba6ffb340bf388f26350aeda225b1"
 
+[[package]]
+name = "bytemuck"
+version = "1.13.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "17febce684fd15d89027105661fec94afb475cb995fbc59d2865198446ba2eea"
+
 [[package]]
 name = "cfg-if"
 version = "1.0.0"
@@ -101,9 +107,11 @@ name = "hbasm"
 version = "0.1.0"
 dependencies = [
  "ariadne",
+ "bytemuck",
  "hashbrown 0.14.0",
  "hbbytecode",
  "lasso",
+ "literify",
  "logos",
  "paste",
 ]
@@ -135,6 +143,26 @@ dependencies = [
  "hashbrown 0.13.2",
 ]
 
+[[package]]
+name = "literify"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "54e4d365df794ed78b4ce1061886f82eae7afa8e3a98ce4c4b0bfd0c777b1175"
+dependencies = [
+ "litrs",
+ "proc-macro2",
+ "quote",
+]
+
+[[package]]
+name = "litrs"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4f17c3668f3cc1132437cdadc93dab05e52d592f06948d3f64828430c36e4a70"
+dependencies = [
+ "proc-macro2",
+]
+
 [[package]]
 name = "log"
 version = "0.4.17"

hbasm/Cargo.toml

@@ -4,10 +4,12 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+ariadne    = "0.3"
+bytemuck   = "1.13"
+hashbrown  = "0.14"
 hbbytecode = { path = "../hbbytecode" }
-paste = "1.0"
+literify   = "0.1"
-hashbrown = "0.14.0"
+paste      = "1.0"
-ariadne = "0.3.0"
 
 [dependencies.lasso]
 version = "0.7"

hbasm/src/lib.rs

@@ -1,10 +1,7 @@
 #![no_std]
-#![feature(error_in_core)]
 
 extern crate alloc;
 
-pub mod text;
-
 mod macros;
 
 use {alloc::vec::Vec, hashbrown::HashSet};
@@ -12,28 +9,26 @@ use {alloc::vec::Vec, hashbrown::HashSet};
 #[derive(Default)]
 pub struct Assembler {
     pub buf: Vec<u8>,
-    sub:     HashSet<usize>,
+    pub sub: HashSet<usize>,
 }
 
-impl Assembler {
+macros::impl_both!(
-    macros::impl_asm!(
+    bbbb(p0: R, p1: R, p2: R, p3: R)
-        bbbb(p0: u8, p1: u8, p2: u8, p3: u8)
+        => [DIR, DIRF, FMAF],
-            => [DIR, DIRF, FMAF],
+    bbb(p0: R, p1: R, p2: R)
-        bbb(p0: u8, p1: u8, p2: u8)
+        => [ADD, SUB, MUL, AND, OR, XOR, SL, SR, SRS, CMP, CMPU, BRC, ADDF, SUBF, MULF],
-            => [ADD, SUB, MUL, AND, OR, XOR, SL, SR, SRS, CMP, CMPU, BRC, ADDF, SUBF, MULF],
+    bbdh(p0: R, p1: R, p2: I, p3: u16)
-        bbdh(p0: u8, p1: u8, p2: impl Imm, p3: u16)
+        => [LD, ST],
-            => [LD, ST],
+    bbd(p0: R, p1: R, p2: I)
-        bbd(p0: u8, p1: u8, p2: impl Imm)
+        => [ADDI, MULI, ANDI, ORI, XORI, SLI, SRI, SRSI, CMPI, CMPUI,
-            => [ADDI, MULI, ANDI, ORI, XORI, SLI, SRI, SRSI, CMPI, CMPUI,
+            BMC, JEQ, JNE, JLT, JGT, JLTU, JGTU, ADDFI, MULFI],
-                BMC, JEQ, JNE, JLT, JGT, JLTU, JGTU, ADDFI, MULFI],
+    bb(p0: R, p1: R)
-        bb(p0: u8, p1: u8)
+        => [NEG, NOT, CP, SWA, NEGF, ITF, FTI],
-            => [NEG, NOT, CP, SWA, NEGF, ITF, FTI],
+    bd(p0: R, p1: I)
-        bd(p0: u8, p1: impl Imm)
+        => [LI, JMP],
-            => [LI, JMP],
+    n()
-        n()
+        => [NOP, ECALL],
-            => [NOP, ECALL],
+);
-    );
-}
 
 pub trait Imm {
     fn insert(&self, asm: &mut Assembler);
@@ -53,13 +48,3 @@ macro_rules! impl_imm_le_bytes {
 }
 
 impl_imm_le_bytes!(u64, i64, f64);
-
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub struct Symbol(pub u64);
-impl Imm for Symbol {
-    #[inline(always)]
-    fn insert(&self, asm: &mut Assembler) {
-        asm.sub.insert(asm.buf.len());
-        asm.buf.extend(self.0.to_le_bytes());
-    }
-}

hbasm/src/macros/asm.rs

@@ -18,47 +18,41 @@ macro_rules! impl_asm_opcodes {
             }
         }
 
-        macros::impl_asm_opcodes!(
+        macros::asm::impl_asm_opcodes!(
             $generic($($param_i: $param_ty),*)
             => [$($rest)*]
         );
     };
 }
 
-macro_rules! gen_impl_asm_insert {
+macro_rules! impl_asm_insert {
-    ($($ty:ident),* $(,)?) => {
+    ($self:expr, $id:ident, I) => {
-        macro_rules! impl_asm_insert {
+        Imm::insert(&$id, $self)
-            $(($self:expr, $id:ident, $ty) => {
+    };
-                $self.buf.extend($id.to_le_bytes())
-            };)*
 
-            ($self:expr, $id:ident, $_:ty) => {
+    ($self:expr, $id:ident, $_:ident) => {
-                Imm::insert(&$id, $self)
+        $self.buf.extend($id.to_le_bytes())
-            };
-        }
     };
 }
 
-gen_impl_asm_insert!(u8, u16, u64);
-
 macro_rules! impl_asm {
     (
         $(
             $ityn:ident
-            ($($param_i:ident: $param_ty:ty),* $(,)?)
+            ($($param_i:ident: $param_ty:ident),* $(,)?)
             => [$($opcode:ident),* $(,)?],
         )*
     ) => {
         paste::paste! {
             $(
                 #[allow(dead_code)]
-                fn [<i_param_ $ityn>](&mut self, opcode: u8, $($param_i: $param_ty),*) {
+                fn [<i_param_ $ityn>](&mut self, opcode: u8, $($param_i: macros::asm::ident_map_ty!($param_ty)),*) {
                     self.buf.push(opcode);
-                    $(macros::impl_asm_insert!(self, $param_i, $param_ty);)*
+                    $(macros::asm::impl_asm_insert!(self, $param_i, $param_ty);)*
                 }
 
-                macros::impl_asm_opcodes!(
+                macros::asm::impl_asm_opcodes!(
-                    [<i_param_ $ityn>]($($param_i: $param_ty),*)
+                    [<i_param_ $ityn>]($($param_i: macros::asm::ident_map_ty!($param_ty)),*)
                     => [$($opcode,)*]
                 );
             )*
@@ -66,7 +60,14 @@ macro_rules! impl_asm {
     };
 }
 
-pub(super) use {impl_asm, impl_asm_opcodes};
+#[rustfmt::skip]
+macro_rules! ident_map_ty {
+    (R)         => { u8 };
+    (I)         => { impl Imm };
+    ($id:ident) => { $id };
+}
+
+pub(crate) use {ident_map_ty, impl_asm, impl_asm_opcodes};
 
 #[allow(clippy::single_component_path_imports)]
-pub(super) use impl_asm_insert;
+pub(crate) use impl_asm_insert;

hbasm/src/macros/mod.rs

@@ -0,0 +1,14 @@
+pub mod asm;
+pub mod text;
+
+macro_rules! impl_both {
+    ($($tt:tt)*) => {
+        impl Assembler {
+            $crate::macros::asm::impl_asm!($($tt)*);
+        }
+
+        $crate::macros::text::gen_text!($($tt)*);
+    };
+}
+
+pub(crate) use impl_both;

hbasm/src/macros/text.rs

@@ -0,0 +1,202 @@
+macro_rules! gen_text {
+    (
+        $(
+            $ityn:ident
+            ($($param_i:ident: $param_ty:ident),* $(,)?)
+            => [$($opcode:ident),* $(,)?],
+        )*
+    ) => {
+        pub mod text {
+            use {
+                crate::{
+                    Assembler,
+                    macros::text::*,
+                },
+                hashbrown::HashMap,
+                lasso::{Key, Rodeo, Spur},
+                logos::{Lexer, Logos, Span},
+            };
+
+            paste::paste!(literify::literify! {
+                #[derive(Clone, Copy, Debug, PartialEq, Eq, Logos)]
+                #[logos(extras = Rodeo)]
+                #[logos(skip r"[ \t\t]+")]
+                #[logos(skip r"-- .*")]
+                pub enum Token {
+                    $($(#[token(~([<$opcode:lower>]), |_| hbbytecode::opcode::[<$opcode:upper>])])*)*
+                    Opcode(u8),
+
+                    #[regex("[0-9]+", |l| l.slice().parse().ok())]
+                    #[regex(
+                        "-[0-9]+",
+                        |lexer| {
+                            Some(u64::from_ne_bytes(lexer.slice().parse::<i64>().ok()?.to_ne_bytes()))
+                        },
+                    )] Integer(u64),
+
+                    #[regex(
+                        "r[0-9]+",
+                        |lexer| match lexer.slice()[1..].parse() {
+                            Ok(n) => Some(n),
+                            _ => None
+                        },
+                    )] Register(u8),
+
+                    #[regex(
+                        r"\p{XID_Start}\p{XID_Continue}*:",
+                        |lexer| lexer.extras.get_or_intern(&lexer.slice()[..lexer.slice().len() - 1]),
+                    )] Label(Spur),
+
+                    #[regex(
+                        r"\p{XID_Start}\p{XID_Continue}*",
+                        |lexer| lexer.extras.get_or_intern(lexer.slice()),
+                    )] Symbol(Spur),
+
+                    #[token("\n")]
+                    #[token(";")] ISep,
+                    #[token(",")] PSep,
+                }
+            });
+
+            #[derive(Copy, Clone, Debug, PartialEq, Eq)]
+            pub enum ErrorKind {
+                UnexpectedToken,
+                InvalidToken,
+                UnexpectedEnd,
+                InvalidSymbol,
+            }
+
+            #[derive(Clone, Debug, PartialEq, Eq)]
+            pub struct Error {
+                pub kind: ErrorKind,
+                pub span: Span,
+            }
+
+            pub fn assemble(asm: &mut Assembler, code: &str) -> Result<(), Error> {
+                pub struct TextAsm<'a> {
+                    asm: &'a mut Assembler,
+                    lexer: Lexer<'a, Token>,
+                    symloc: HashMap<Spur, usize>,
+                }
+
+                impl<'a> TextAsm<'a> {
+                    fn next(&mut self) -> Result<Token, ErrorKind> {
+                        match self.lexer.next() {
+                            Some(Ok(t))   => Ok(t),
+                            Some(Err(())) => Err(ErrorKind::InvalidToken),
+                            None          => Err(ErrorKind::UnexpectedEnd),
+                        }
+                    }
+
+                    #[inline(always)]
+                    fn run(&mut self) -> Result<(), ErrorKind> {
+                        loop {
+                            match self.lexer.next() {
+                                Some(Ok(Token::Opcode(op))) => {
+                                    match op {
+                                        $(
+                                            $(hbbytecode::opcode::$opcode)|* => paste::paste!({
+                                                param_extract_itm!(self, $($param_i: $param_ty),*);
+                                                self.asm.[<i_param_ $ityn>](op, $($param_i),*);
+                                            }),
+                                        )*
+                                        _ => unreachable!(),
+                                    }
+                                }
+                                Some(Ok(Token::Label(lbl))) => {
+                                    self.symloc.insert(lbl, self.asm.buf.len());
+                                }
+                                Some(Ok(Token::ISep)) => (),
+                                Some(Ok(_))           => return Err(ErrorKind::UnexpectedToken),
+                                Some(Err(()))         => return Err(ErrorKind::InvalidToken),
+                                None                  => return Ok(()),
+                            }
+                        }
+                    }
+                }
+
+                let mut asm = TextAsm {
+                    asm,
+                    lexer: Token::lexer(code),
+                    symloc: HashMap::default(),
+                };
+
+                asm.run()
+                    .map_err(|kind| Error { kind, span: asm.lexer.span() })?;
+                
+                for &loc in &asm.asm.sub {
+                    let val = asm.symloc
+                        .get(
+                            &Spur::try_from_usize(bytemuck::pod_read_unaligned::<u64>(&asm.asm.buf[loc..loc+core::mem::size_of::<u64>()]) as _)
+                                .unwrap()
+                        )
+                        .ok_or(Error { kind: ErrorKind::InvalidSymbol, span: 0..0 })?
+                        .to_le_bytes();
+
+                    asm.asm.buf[loc..]
+                        .iter_mut()
+                        .zip(val)
+                        .for_each(|(dst, src)| *dst = src);
+                }
+
+                Ok(())
+            }
+
+            enum InternalImm {
+                Const(u64),
+                Named(Spur),
+            }
+
+            impl $crate::Imm for InternalImm {
+                #[inline]
+                fn insert(&self, asm: &mut Assembler) {
+                    match self {
+                        Self::Const(a) => a.insert(asm),
+                        Self::Named(a) => {
+                            asm.sub.insert(asm.buf.len());
+                            asm.buf.extend((a.into_usize() as u64).to_le_bytes());
+                        },
+                    }
+                }
+            }
+        }
+    };
+}
+
+macro_rules! extract_pat {
+    ($self:expr, $pat:pat) => {
+        let $pat = $self.next()?
+            else { return Err(ErrorKind::UnexpectedToken) };
+    };
+}
+
+macro_rules! extract {
+    ($self:expr, R, $id:ident) => {
+        extract_pat!($self, Token::Register($id));
+    };
+
+    ($self:expr, I, $id:ident) => {
+        let $id = match $self.next()? {
+            Token::Integer(a) => InternalImm::Const(a),
+            Token::Symbol(a) => InternalImm::Named(a),
+            _ => return Err(ErrorKind::UnexpectedToken),
+        };
+    };
+
+    ($self:expr, u16, $id:ident) => {
+        extract_pat!($self, Token::Integer($id));
+        let $id = u16::try_from($id).map_err(|_| ErrorKind::InvalidToken)?;
+    };
+}
+
+macro_rules! param_extract_itm {
+    ($self:expr, $($id:ident: $ty:ident)? $(, $($tt:tt)*)?) => {
+        $(extract!($self, $ty, $id);)?
+        $(
+            extract_pat!($self, Token::PSep);
+            param_extract_itm!($self, $($tt)*);
+        )?
+    };
+}
+
+pub(crate) use {extract, extract_pat, gen_text, param_extract_itm};

hbasm/src/main.rs

@@ -1,3 +1,7 @@
+use std::io::Write;
+
+use hbasm::Assembler;
+
 use {
     ariadne::{ColorGenerator, Label, Report, ReportKind, Source},
     std::{
@@ -10,9 +14,8 @@ fn main() -> Result<(), Box<dyn Error>> {
     let mut code = String::new();
     stdin().read_to_string(&mut code)?;
 
-    let mut buf = vec![];
+    let mut assembler = Assembler::default();
-
+    if let Err(e) = hbasm::text::assemble(&mut assembler, &code) {
-    if let Err(e) = hbasm::text::assembly(&code, &mut buf) {
         let mut colors = ColorGenerator::new();
 
         let e_code = match e.kind {
@@ -24,22 +27,28 @@ fn main() -> Result<(), Box<dyn Error>> {
         let message = match e.kind {
             hbasm::text::ErrorKind::UnexpectedToken => "This token is not expected!",
             hbasm::text::ErrorKind::InvalidToken => "The token is not valid!",
-            hbasm::text::ErrorKind::UnexpectedEnd => "The assembler reached the end of input unexpectedly!",
+            hbasm::text::ErrorKind::UnexpectedEnd => {
-            hbasm::text::ErrorKind::InvalidSymbol => "This referenced symbol doesn't have a corresponding label!",
+                "The assembler reached the end of input unexpectedly!"
+            }
+            hbasm::text::ErrorKind::InvalidSymbol => {
+                "This referenced symbol doesn't have a corresponding label!"
+            }
         };
         let a = colors.next();
 
         Report::build(ReportKind::Error, "engine_internal", e.span.clone().start)
-        .with_code(e_code)
+            .with_code(e_code)
-        .with_message(format!("{:?}", e.kind))
+            .with_message(format!("{:?}", e.kind))
-        .with_label(
+            .with_label(
-            Label::new(("engine_internal", e.span.clone()))
+                Label::new(("engine_internal", e.span.clone()))
-                .with_message(message)
+                    .with_message(message)
-                .with_color(a),
+                    .with_color(a),
-        )
+            )
-        .finish()
+            .finish()
-        .eprint(("engine_internal", Source::from(&code)))
+            .eprint(("engine_internal", Source::from(&code)))
-        .unwrap();
+            .unwrap();
+    } else {
+        std::io::stdout().lock().write_all(&assembler.buf).unwrap();
     }
 
     Ok(())

hbasm/src/text.rs

@@ -1,273 +0,0 @@
-extern crate alloc;
-use alloc::vec::Vec;
-
-use {
-    core::fmt::{Display, Formatter},
-    hashbrown::HashMap,
-    lasso::{Rodeo, Spur},
-    logos::{Lexer, Logos, Span},
-};
-
-macro_rules! tokendef {
-    ($($opcode:literal),* $(,)?) => {
-        paste::paste! {
-            #[derive(Clone, Copy, Debug, PartialEq, Eq, Logos)]
-            #[logos(extras = Rodeo)]
-            #[logos(skip r"[ \t\f]+")]
-            #[logos(skip r"-- .*")]
-            pub enum Token {
-                $(#[token($opcode, |_| hbbytecode::opcode::[<$opcode:upper>])])*
-                OpCode(u8),
-
-                #[regex("[0-9]+", |l| l.slice().parse().ok())]
-                #[regex(
-                    "-[0-9]+",
-                    |lexer| {
-                        Some(u64::from_ne_bytes(lexer.slice().parse::<i64>().ok()?.to_ne_bytes()))
-                    },
-                )] Integer(u64),
-
-                #[regex(
-                    "r[0-9]+",
-                    |lexer| match lexer.slice()[1..].parse() {
-                        Ok(n) => Some(n),
-                        _ => None
-                    },
-                )] Register(u8),
-
-                #[regex(
-                    r"\p{XID_Start}\p{XID_Continue}*:",
-                    |lexer| lexer.extras.get_or_intern(&lexer.slice()[..lexer.slice().len() - 1]),
-                )] Label(Spur),
-
-                #[regex(
-                    r"\p{XID_Start}\p{XID_Continue}*",
-                    |lexer| lexer.extras.get_or_intern(lexer.slice()),
-                )] Symbol(Spur),
-
-                #[token("\n")]
-                #[token(";")] ISep,
-                #[token(",")] PSep,
-            }
-        }
-    };
-}
-
-#[rustfmt::skip]
-tokendef![
-    "nop", "add", "sub", "mul", "and", "or", "xor", "sl", "sr", "srs", "cmp", "cmpu",
-    "dir", "neg", "not", "addi", "muli", "andi", "ori", "xori", "sli", "sri", "srsi",
-    "cmpi", "cmpui", "cp", "swa", "li", "ld", "st", "bmc", "brc", "jmp", "jeq", "jne",
-    "jlt", "jgt", "jltu", "jgtu", "ecall", "addf", "subf", "mulf", "dirf", "fmaf", "negf",
-    "itf", "fti", "addfi", "mulfi",
-];
-
-#[derive(Copy, Clone, Debug, PartialEq, Eq)]
-pub enum ErrorKind {
-    UnexpectedToken,
-    InvalidToken,
-    UnexpectedEnd,
-    InvalidSymbol,
-}
-
-#[derive(Clone, Debug, PartialEq, Eq)]
-pub struct Error {
-    pub kind: ErrorKind,
-    pub span: Span,
-}
-
-impl Display for Error {
-    fn fmt(&self, f: &mut Formatter<'_>) -> core::fmt::Result {
-        write!(f, "Error {:?} at {:?}", self.kind, self.span)
-    }
-}
-
-impl core::error::Error for Error {}
-
-macro_rules! expect_matches {
-    ($self:expr, $($pat:pat),* $(,)?) => {$(
-        let $pat = $self.next()?
-            else { return Err(ErrorKind::UnexpectedToken) };
-    )*}
-}
-
-pub fn assembly(code: &str, buf: &mut Vec<u8>) -> Result<(), Error> {
-    struct Assembler<'a> {
-        lexer: Lexer<'a, Token>,
-        buf: &'a mut Vec<u8>,
-        label_map: HashMap<Spur, u64>,
-        to_sub_label: HashMap<usize, Spur>,
-    }
-
-    impl<'a> Assembler<'a> {
-        fn next(&mut self) -> Result<Token, ErrorKind> {
-            match self.lexer.next() {
-                Some(Ok(t)) => Ok(t),
-                Some(Err(())) => Err(ErrorKind::InvalidToken),
-                None => Err(ErrorKind::UnexpectedEnd),
-            }
-        }
-
-        fn assemble(&mut self) -> Result<(), ErrorKind> {
-            use hbbytecode::opcode::*;
-            loop {
-                match self.lexer.next() {
-                    Some(Ok(Token::OpCode(op))) => {
-                        self.buf.push(op);
-                        match op {
-                            NOP | ECALL => Ok(()),
-                            DIR | DIRF => {
-                                expect_matches!(
-                                    self,
-                                    Token::Register(r0),
-                                    Token::PSep,
-                                    Token::Register(r1),
-                                    Token::PSep,
-                                    Token::Register(r2),
-                                    Token::PSep,
-                                    Token::Register(r3),
-                                );
-                                self.buf.extend([r0, r1, r2, r3]);
-                                Ok(())
-                            }
-                            ADD..=CMPU | ADDF..=MULF => {
-                                expect_matches!(
-                                    self,
-                                    Token::Register(r0),
-                                    Token::PSep,
-                                    Token::Register(r1),
-                                    Token::PSep,
-                                    Token::Register(r2),
-                                );
-                                self.buf.extend([r0, r1, r2]);
-                                Ok(())
-                            }
-                            BRC => {
-                                expect_matches!(
-                                    self,
-                                    Token::Register(r0),
-                                    Token::PSep,
-                                    Token::Register(r1),
-                                    Token::PSep,
-                                    Token::Integer(count),
-                                );
-                                self.buf.extend([
-                                    r0,
-                                    r1,
-                                    u8::try_from(count).map_err(|_| ErrorKind::UnexpectedToken)?,
-                                ]);
-                                Ok(())
-                            }
-                            NEG..=NOT | CP..=SWA | NEGF..=FTI => {
-                                expect_matches!(
-                                    self,
-                                    Token::Register(r0),
-                                    Token::PSep,
-                                    Token::Register(r1),
-                                );
-                                self.buf.extend([r0, r1]);
-                                Ok(())
-                            }
-                            LI | JMP => {
-                                expect_matches!(self, Token::Register(r0), Token::PSep);
-                                self.buf.push(r0);
-                                self.insert_imm()?;
-                                Ok(())
-                            }
-                            ADDI..=CMPUI | BMC | JEQ..=JGTU | ADDFI..=MULFI => {
-                                expect_matches!(
-                                    self,
-                                    Token::Register(r0),
-                                    Token::PSep,
-                                    Token::Register(r1),
-                                    Token::PSep,
-                                );
-                                self.buf.extend([r0, r1]);
-                                self.insert_imm()?;
-                                Ok(())
-                            }
-                            LD..=ST => {
-                                expect_matches!(
-                                    self,
-                                    Token::Register(r0),
-                                    Token::PSep,
-                                    Token::Register(r1),
-                                    Token::PSep,
-                                    Token::Integer(offset),
-                                    Token::PSep,
-                                    Token::Integer(len),
-                                );
-                                self.buf.extend([r0, r1]);
-                                self.buf.extend(offset.to_le_bytes());
-                                self.buf.extend(
-                                    u16::try_from(len)
-                                        .map_err(|_| ErrorKind::InvalidToken)?
-                                        .to_le_bytes(),
-                                );
-                                Ok(())
-                            }
-                            _ => unreachable!(),
-                        }?;
-                        match self.next() {
-                            Ok(Token::ISep) => (),
-                            Ok(_) => return Err(ErrorKind::UnexpectedToken),
-                            Err(ErrorKind::UnexpectedEnd) => return Ok(()),
-                            Err(e) => return Err(e),
-                        }
-                    }
-                    Some(Ok(Token::Label(lbl))) => {
-                        self.label_map.insert(lbl, self.buf.len() as u64);
-                    }
-                    Some(Ok(Token::ISep)) => (),
-                    Some(Ok(_)) => return Err(ErrorKind::UnexpectedToken),
-                    Some(Err(())) => return Err(ErrorKind::InvalidToken),
-                    None => return Ok(()),
-                }
-            }
-        }
-
-        fn link_local_syms(&mut self) -> Result<(), ErrorKind> {
-            for (ix, sym) in &self.to_sub_label {
-                self.label_map
-                    .get(sym)
-                    .ok_or(ErrorKind::InvalidSymbol)?
-                    .to_le_bytes()
-                    .iter()
-                    .enumerate()
-                    .for_each(|(i, b)| {
-                        self.buf[ix + i] = *b;
-                    });
-            }
-
-            Ok(())
-        }
-
-        fn insert_imm(&mut self) -> Result<(), ErrorKind> {
-            let imm = match self.next()? {
-                Token::Integer(i) => i.to_le_bytes(),
-                Token::Symbol(s) => {
-                    self.to_sub_label.insert(self.buf.len(), s);
-                    [0; 8]
-                }
-                _ => return Err(ErrorKind::UnexpectedToken),
-            };
-            self.buf.extend(imm);
-            Ok(())
-        }
-    }
-
-    let mut asm = Assembler {
-        lexer: Token::lexer(code),
-        label_map: Default::default(),
-        to_sub_label: Default::default(),
-        buf,
-    };
-
-    asm.assemble().map_err(|kind| Error {
-        kind,
-        span: asm.lexer.span(),
-    })?;
-
-    asm.link_local_syms()
-        .map_err(|kind| Error { kind, span: 0..0 })
-}