START OF COMPILER

.gitignore

@@ -1 +1,2 @@
 /target
+/build

data/err.lang

@@ -20,3 +20,12 @@ fn main() {
         b
     };
 }
+
+fn test() {
+    let r = 3;
+    let a = }
+}
+
+fn test2() {
+
+}

data/test.lang

@@ -0,0 +1,4 @@
+fn main() {
+    let x = 3;
+    print(x);
+}

src/compiler/mod.rs

@@ -0,0 +1,42 @@
+use std::{
+    fs::{create_dir_all, OpenOptions},
+    os::unix::fs::OpenOptionsExt,
+    path::Path,
+    process::Command,
+};
+
+mod riscv64;
+mod program;
+mod target;
+
+pub fn main() {
+    use std::io::prelude::*;
+    let dir = Path::new("build");
+    create_dir_all(dir).expect("Failed to create or confirm build directory");
+    let name = Path::new("test");
+    let path = dir.join(name);
+    let path = path.as_os_str();
+    let mut file = OpenOptions::new()
+        .create(true)
+        .write(true)
+        .truncate(true)
+        .mode(0o750)
+        .open(path)
+        .expect("Failed to create file");
+    file.write_all(&riscv64::gen())
+        .expect("Failed to write to file");
+    file.sync_all().expect("Failed to sync file");
+    if let Ok(mut process) = Command::new("qemu-riscv64").arg(path).spawn() {
+        if let Ok(status) = process.wait() {
+            if status.code().is_none_or(|c| c != 0) {
+                println!("{}", status);
+            }
+        }
+    }
+}
+
+//     qemu-riscv64 -g 1234 test &
+//     riscv64-linux-gnu-gdb -q \
+//         -ex "target remote :1234" \
+//         test
+

src/compiler/program.rs

@@ -0,0 +1,53 @@
+use std::collections::HashMap;
+
+pub struct Program {
+    data: Vec<u8>,
+    ro_map: HashMap<String, usize>,
+}
+
+impl Program {
+    pub fn new(data: HashMap<String, Vec<u8>>) -> Self {
+        let mut ro_data = Vec::new();
+        let mut ro_map = HashMap::new();
+        for (key, val) in data {
+            ro_map.insert(key, ro_data.len());
+            ro_data.extend(val);
+        }
+        Self {
+            data: ro_data,
+            ro_map,
+        }
+    }
+}
+
+pub fn create_program<I: Instr>(
+    ro_data: HashMap<String, Vec<u8>>,
+    functions: Vec<Function<I>>,
+) -> Vec<u8> {
+    let mut data = Vec::new();
+    let mut ro_map = HashMap::new();
+    for (key, val) in ro_data {
+        ro_map.insert(key, data.len());
+        data.extend(val);
+    }
+    // let mut fn_map = HashMap::new();
+    for fun in functions {
+        for i in fun.instructions {
+            data.extend(i.to_le_bytes());
+        }
+    }
+    data
+}
+
+pub struct Function<I: Instr> {
+    label: String,
+    instructions: Vec<I>,
+}
+
+pub trait Instr {
+    fn to_le_bytes(&self) -> impl IntoIterator<Item = u8>;
+}
+
+struct SymbolInstr {
+    i: usize
+}

src/compiler/riscv64/asm.rs

@@ -0,0 +1,2 @@
+pub enum Instruction {
+}

src/compiler/riscv64/elf.rs

@@ -0,0 +1,101 @@
+#[repr(C)]
+pub struct ELF64Header {
+    magic: u32,
+    class: u8,
+    endianness: u8,
+    ei_version: u8,
+    os_abi: u8,
+    os_abi_ver: u8,
+    pad: [u8; 7],
+    ty: u16,
+    machine: u16,
+    e_version: u32,
+    entry: u64,
+    program_header_offset: u64,
+    section_header_offset: u64,
+    flags: u32,
+    header_size: u16,
+    program_header_entry_size: u16,
+    program_header_num: u16,
+    section_header_entry_size: u16,
+    section_header_num: u16,
+    section_header_str_idx: u16,
+}
+
+#[repr(C)]
+pub struct ProgramHeader {
+    ty: u32,
+    flags: u32,
+    offset: u64,
+    vaddr: u64,
+    paddr: u64,
+    filesz: u64,
+    memsz: u64,
+    align: u64,
+}
+
+#[repr(C)]
+pub struct SectionHeader {
+    name_idx: u32,
+    ty: u32,
+    flags: u64,
+    addr: u64,
+    offset: u64,
+    size: u64,
+    link: u32,
+    info: u32,
+    addr_align: u64,
+    entry_size: u64,
+}
+
+pub fn create(program: Vec<u8>, start_offset: u64) -> Vec<u8> {
+    let addr_start = 0x1000;
+    let page_size = 0x1000;
+    let progam_size = std::mem::size_of_val(&program[..]) as u64;
+    let program_header = ProgramHeader {
+        ty: 0x1,      // LOAD
+        flags: 0b101, // executable, readable
+        offset: 0x0,
+        vaddr: addr_start,
+        paddr: addr_start,
+        filesz: progam_size,
+        memsz: progam_size,
+        align: page_size,
+    };
+    let header_len = (size_of::<ELF64Header>() + size_of::<ProgramHeader>()) as u64;
+    let program_pos = header_len;
+    let header = ELF64Header {
+        magic: 0x7f_45_4c_46u32.swap_bytes(),
+        class: 0x2,      // 64 bit
+        endianness: 0x1, // little endian
+        ei_version: 0x1,
+        os_abi: 0x0, // system-v
+        os_abi_ver: 0x0,
+        pad: [0x0; 7],
+        ty: 0x2,       // executable
+        machine: 0xf3, // risc-v
+        e_version: 0x1,
+        entry: addr_start + program_pos + start_offset,
+        program_header_offset: size_of::<ELF64Header>() as u64,
+        section_header_offset: 0x0,
+        // C ABI (16 bit instruction align) + double precision floats
+        flags: 0x1 | 0x4,
+        header_size: size_of::<ELF64Header>() as u16,
+        program_header_entry_size: size_of::<ProgramHeader>() as u16,
+        program_header_num: 0x1,
+        section_header_entry_size: size_of::<SectionHeader>() as u16,
+        section_header_num: 0x0,
+        section_header_str_idx: 0x0,
+    };
+    let mut bytes: Vec<u8> = Vec::new();
+    unsafe {
+        bytes.extend(as_u8_slice(&header));
+        bytes.extend(as_u8_slice(&program_header));
+        bytes.extend(program);
+    }
+    bytes
+}
+
+unsafe fn as_u8_slice<T: Sized>(p: &T) -> &[u8] {
+    core::slice::from_raw_parts((p as *const T) as *const u8, size_of::<T>())
+}

src/compiler/riscv64/instruction/base.rs

@@ -0,0 +1,58 @@
+use super::{Reg, OPCODE_MASK};
+use crate::{compiler::program::Instr, util::{bit, bits, in_bit_range}};
+
+pub struct Instruction(u32);
+
+use Instruction as I;
+
+impl Instr for Instruction {
+    fn to_le_bytes(&self) -> impl IntoIterator<Item = u8> {
+        self.0.to_le_bytes().into_iter()
+    }
+}
+
+pub const fn r_type(funct7: u32, rs2: Reg, rs1: Reg, funct3: u32, rd: Reg, opcode: u32) -> I {
+    I((funct7 << 25)
+        + (rs2.val() << 20)
+        + (rs1.val() << 15)
+        + (funct3 << 12)
+        + (rd.val() << 7)
+        + opcode)
+}
+pub const fn i_type(imm: i32, rs1: Reg, funct3: u32, rd: Reg, opcode: u32) -> I {
+    debug_assert!(in_bit_range(imm, 11, 0));
+    I((bits(imm, 11, 0) << 20) + (rs1.val() << 15) + (funct3 << 12) + (rd.val() << 7) + opcode)
+}
+pub const fn s_type(rs2: Reg, rs1: Reg, funct3: u32, imm: i32, opcode: u32) -> I {
+    debug_assert!(in_bit_range(imm, 11, 0));
+    I((bits(imm, 11, 5) << 25)
+        + (rs2.val() << 20)
+        + (rs1.val() << 15)
+        + (funct3 << 12)
+        + (bits(imm, 4, 0) << 7)
+        + opcode)
+}
+pub const fn b_type(rs2: Reg, rs1: Reg, funct3: u32, imm: i32, opcode: u32) -> I {
+    debug_assert!(in_bit_range(imm, 12, 1));
+    I((bit(imm, 12) << 31)
+        + (bits(imm, 10, 5) << 25)
+        + (rs2.val() << 20)
+        + (rs1.val() << 15)
+        + (funct3 << 8)
+        + (bits(imm, 4, 1) << 8)
+        + (bit(imm, 11) << 7)
+        + opcode)
+}
+pub const fn u_type(imm: i32, rd: Reg, opcode: u32) -> I {
+    debug_assert!(in_bit_range(imm, 31, 12));
+    I((bits(imm, 31, 12) << 12) + (rd.val() << 7) + opcode)
+}
+pub const fn j_type(imm: i32, rd: Reg, opcode: u32) -> I {
+    debug_assert!(in_bit_range(imm, 20, 1));
+    I((bit(imm, 20) << 31)
+        + (bits(imm, 10, 1) << 21)
+        + (bit(imm, 11) << 20)
+        + (bits(imm, 19, 12) << 12)
+        + (rd.val() << 7)
+        + opcode)
+}

src/compiler/riscv64/instruction/func.rs

@@ -0,0 +1,20 @@
+pub mod op {
+    pub const ADD : u32 = 0b000;
+    pub const SLL : u32 = 0b001;
+    pub const SLT : u32 = 0b010;
+    pub const SLTU: u32 = 0b011;
+    pub const XOR : u32 = 0b100;
+    pub const SR  : u32 = 0b101;
+    pub const OR  : u32 = 0b110;
+    pub const AND : u32 = 0b111;
+}
+
+pub mod width {
+    pub const B : u32 = 0b000;
+    pub const H : u32 = 0b001;
+    pub const W : u32 = 0b010;
+    pub const D : u32 = 0b011;
+    pub const BU: u32 = 0b100;
+    pub const HU: u32 = 0b101;
+    pub const WU: u32 = 0b110;
+}

src/compiler/riscv64/instruction/mod.rs

@@ -0,0 +1,53 @@
+mod base;
+mod reg;
+mod opcode;
+mod func;
+
+use base::*;
+pub use reg::*;
+use Instruction as I;
+use opcode::*;
+use func::{op::*, width};
+
+pub const fn ecall() -> I {
+    i_type(0, zero, 0, zero, SYSTEM)
+}
+pub const fn ebreak() -> I {
+    i_type(1, zero, 0, zero, SYSTEM)
+}
+pub const fn auipc(dest: Reg, imm: i32) -> I {
+    u_type(imm, dest, AUIPC)
+}
+pub const fn ld(dest: Reg, offset: i32, base: Reg) -> I {
+    i_type(offset, base, width::D, dest, LOAD)
+}
+pub const fn lw(dest: Reg, offset: i32, base: Reg) -> I {
+    i_type(offset, base, width::W, dest, LOAD)
+}
+pub const fn lb(dest: Reg, offset: i32, base: Reg) -> I {
+    i_type(offset, base, width::B, dest, LOAD)
+}
+pub const fn sb(src: Reg, offset: i32, base: Reg) -> I {
+    s_type(src, base, width::B, offset, STORE)
+}
+pub const fn sw(src: Reg, offset: i32, base: Reg) -> I {
+    s_type(src, base, width::W, offset, STORE)
+}
+pub const fn sd(src: Reg, offset: i32, base: Reg) -> I {
+    s_type(src, base, width::D, offset, STORE)
+}
+pub const fn addi(dest: Reg, src: Reg, imm: i32) -> I {
+    i_type(imm, src, ADD, dest, IMM_OP)
+}
+pub const fn jal(offset: i32, dest: Reg) -> I {
+    j_type(offset, dest, JAL)
+}
+
+// pseudo instructions that map to a single instruction
+
+pub const fn j(offset: i32) -> I {
+    jal(offset, zero)
+}
+pub const fn mv(dest: Reg, src: Reg) -> I {
+    addi(dest, src, 0)
+}

src/compiler/riscv64/instruction/opcode.rs

@@ -0,0 +1,9 @@
+pub const OPCODE_MASK: u32 = 0b1111111;
+
+pub const SYSTEM: u32 = 0b1110011;
+pub const LOAD  : u32 = 0b0000011;
+pub const STORE : u32 = 0b0100011;
+pub const AUIPC : u32 = 0b0010111;
+pub const IMM_OP: u32 = 0b0010011;
+pub const OP    : u32 = 0b0110011;
+pub const JAL   : u32 = 0b1101111;

src/compiler/riscv64/instruction/reg.rs

@@ -0,0 +1,93 @@
+#![allow(non_upper_case_globals)]
+
+pub struct Reg(u8);
+
+/// hard wired 0
+pub const zero: Reg = Reg(0);
+/// return address
+pub const ra: Reg = Reg(1);
+/// stack pointer
+pub const sp: Reg = Reg(2);
+/// global pointer
+pub const gp: Reg = Reg(3);
+/// thread pointer
+pub const tp: Reg = Reg(4);
+/// temp / alternate link
+pub const t0: Reg = Reg(5);
+pub const t1: Reg = Reg(6);
+pub const t2: Reg = Reg(7);
+
+pub const fp: Reg = Reg(8);
+pub const s0: Reg = Reg(8);
+pub const s1: Reg = Reg(9);
+
+pub const a0: Reg = Reg(10);
+pub const a1: Reg = Reg(11);
+pub const a2: Reg = Reg(12);
+pub const a3: Reg = Reg(13);
+pub const a4: Reg = Reg(14);
+pub const a5: Reg = Reg(15);
+pub const a6: Reg = Reg(16);
+pub const a7: Reg = Reg(17);
+
+pub const s2: Reg = Reg(18);
+pub const s3: Reg = Reg(19);
+pub const s4: Reg = Reg(20);
+pub const s5: Reg = Reg(21);
+pub const s6: Reg = Reg(22);
+pub const s7: Reg = Reg(23);
+pub const s8: Reg = Reg(24);
+pub const s9: Reg = Reg(25);
+pub const s10: Reg = Reg(26);
+pub const s11: Reg = Reg(27);
+
+pub const t3: Reg = Reg(28);
+pub const t4: Reg = Reg(29);
+pub const t5: Reg = Reg(30);
+pub const t6: Reg = Reg(31);
+
+
+
+pub const ft0: Reg = Reg(0);
+pub const ft1: Reg = Reg(1);
+pub const ft2: Reg = Reg(2);
+pub const ft3: Reg = Reg(3);
+pub const ft4: Reg = Reg(4);
+pub const ft5: Reg = Reg(5);
+pub const ft6: Reg = Reg(6);
+pub const ft7: Reg = Reg(7);
+
+pub const fs0: Reg = Reg(8);
+pub const fs1: Reg = Reg(9);
+
+pub const fa0: Reg = Reg(10);
+pub const fa1: Reg = Reg(11);
+pub const fa2: Reg = Reg(12);
+pub const fa3: Reg = Reg(13);
+pub const fa4: Reg = Reg(14);
+pub const fa5: Reg = Reg(15);
+pub const fa6: Reg = Reg(16);
+pub const fa7: Reg = Reg(17);
+
+pub const fs2: Reg = Reg(18);
+pub const fs3: Reg = Reg(19);
+pub const fs4: Reg = Reg(20);
+pub const fs5: Reg = Reg(21);
+pub const fs6: Reg = Reg(22);
+pub const fs7: Reg = Reg(23);
+pub const fs8: Reg = Reg(24);
+pub const fs9: Reg = Reg(25);
+pub const fs10: Reg = Reg(26);
+pub const fs11: Reg = Reg(27);
+
+pub const ft8: Reg = Reg(28);
+pub const ft9: Reg = Reg(29);
+pub const ft10: Reg = Reg(30);
+pub const ft11: Reg = Reg(31);
+
+impl Reg {
+    #[inline]
+    pub const fn val(&self) -> u32 {
+        self.0 as u32
+    }
+}

src/compiler/riscv64/mod.rs

@@ -0,0 +1,33 @@
+use crate::compiler::program::Instr;
+mod elf;
+mod instruction;
+mod asm;
+
+use instruction::*;
+
+pub fn gen() -> Vec<u8> {
+    let mut program = Vec::new();
+    let msg = b"Hello world!\n";
+    program.extend(msg);
+    program.resize(((program.len() - 1) / 4 + 1) * 4, 0);
+    let start = program.len() as u64;
+    let instructions = [
+        auipc(t0, 0),
+        addi(t0, t0, -(start as i32)),
+        addi(a0, zero, 1),
+        mv(a1, t0),
+        addi(a2, zero, msg.len() as i32),
+        addi(a7, zero, 64),
+        addi(t0, zero, 200),
+        ecall(),
+        // exit
+        addi(a0, zero, 0),
+        addi(a7, zero, 93),
+        ecall(),
+        j(0),
+    ];
+    for i in instructions {
+        program.extend(i.to_le_bytes());
+    }
+    elf::create(program, start)
+}

src/compiler/target.rs

@@ -0,0 +1,7 @@
+pub trait Target {
+    type Reg;
+}
+
+pub trait RegType {
+    type Size;
+}

src/main.rs

@@ -1,17 +1,11 @@
 #![feature(box_patterns)]
+#![feature(const_unbounded_shifts)]
+#![feature(unbounded_shifts)]
 
 mod util;
-mod v1;
-mod v2;
+mod compiler;
+mod parser;
 
 fn main() {
-    let arg = std::env::args_os().nth(1);
-    if let Some(path) = arg {
-        let file = std::fs::read_to_string(path).expect("failed to read file");
-        println!("{file}");
-        v1::parse_file(&file);
-        // v2::parse_file(&file);
-    } else {
-        v1::run_stdin();
-    }
+    compiler::main();
 }

src/parser/mod.rs

@@ -0,0 +1,14 @@
+mod v1;
+mod v2;
+
+pub fn main() {
+    let arg = std::env::args_os().nth(1);
+    if let Some(path) = arg {
+        let file = std::fs::read_to_string(path).expect("failed to read file");
+        println!("{file}");
+        v1::parse_file(&file);
+        // v2::parse_file(&file);
+    } else {
+        v1::run_stdin();
+    }
+}

src/parser/v1/expr.rs

@@ -1,13 +1,13 @@
 use std::fmt::{Debug, Write};
 
 use super::token::{Symbol, Token};
-use super::{Body, Node, Parsable, ParserError, ParserErrors, TokenCursor, Val};
+use super::{Body, Node, Parsable, ParserError, ParserErrors, TokenCursor, Literal};
 
 pub type ExprNode = Node<Box<Expr>>;
 
 #[derive(Clone)]
 pub enum Expr {
-    Val(Node<Val>),
+    Lit(Node<Literal>),
     Ident(String),
     BinaryOp(Operator, ExprNode, ExprNode),
     Block(Node<Body>),
@@ -30,7 +30,7 @@ pub enum Operator {
 impl Expr {
     pub fn ended_with_error(&self) -> bool {
         match self {
-            Expr::Val(_) => false,
+            Expr::Lit(_) => false,
             Expr::Ident(_) => false,
             Expr::BinaryOp(_, _, e) => e.is_err() || e.as_ref().is_ok_and(|e| e.ended_with_error()),
             Expr::Block(b) => b.is_err(),
@@ -48,8 +48,8 @@ impl Parsable for Expr {
             cursor.next();
             if cursor.expect_peek()?.is_symbol(Symbol::CloseParen) {
                 cursor.next();
-                return Ok(Expr::Val(Node::new(
-                    Val::Unit,
+                return Ok(Expr::Lit(Node::new(
+                    Literal::Unit,
                     cursor.next_pos().char_span(),
                 )));
             }
@@ -62,7 +62,7 @@ impl Parsable for Expr {
         } else if next.is_symbol(Symbol::OpenCurly) {
             Self::Block(Node::parse(cursor, errors))
         } else if let Some(val) = Node::maybe_parse(cursor, errors) {
-            Self::Val(val)
+            Self::Lit(val)
         } else {
             let next = cursor.peek().unwrap();
             match &next.token {
@@ -172,7 +172,7 @@ impl Operator {
 impl Debug for Expr {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
-            Expr::Val(c) => c.fmt(f)?,
+            Expr::Lit(c) => c.fmt(f)?,
             Expr::Ident(n) => f.write_str(n)?,
             Expr::Block(b) => b.fmt(f)?,
             Expr::BinaryOp(op, e1, e2) => {

src/parser/v1/mod.rs

@@ -1,8 +1,22 @@
 use std::io::{stdout, BufRead, BufReader};
 
-mod parser;
+mod body;
+mod cursor;
+mod error;
+mod expr;
+mod module;
+mod node;
+mod token;
+mod val;
 
-use parser::{Module, Node, ParserErrors, Statement, TokenCursor};
+pub use body::*;
+pub use cursor::*;
+pub use error::*;
+pub use expr::*;
+pub use module::*;
+pub use node::*;
+pub use val::*;
+use token::*;
 
 pub fn parse_file(file: &str) {
     let mut errors = ParserErrors::new();
@@ -10,8 +24,9 @@ pub fn parse_file(file: &str) {
     if let Ok(module) = node.as_ref() {
         println!("{module:#?}");
     };
+    let out = &mut stdout();
     for err in errors.errs {
-        err.write_for(&mut stdout(), file).unwrap();
+        err.write_for(out, file).unwrap();
     }
 }
 
@@ -20,12 +35,12 @@ pub fn run_stdin() {
         let mut errors = ParserErrors::new();
         let str = &line.expect("failed to read line");
         let mut cursor = TokenCursor::from(&str[..]);
-        let out = &mut stdout();
         if let Ok(expr) = Node::<Statement>::parse(&mut cursor, &mut errors).as_ref() {
             println!("{:?}", expr);
         }
+        let out = &mut stdout();
         for err in errors.errs {
-            err.write_for(&mut stdout(), str).unwrap();
+            err.write_for(out, str).unwrap();
         }
     }
 }

src/parser/v1/module.rs

@@ -1,21 +1,6 @@
 use std::fmt::Debug;
 
-mod body;
-mod cursor;
-mod error;
-mod expr;
-mod token;
-mod val;
-mod node;
-
-pub use body::*;
-pub use cursor::*;
-pub use error::*;
-pub use expr::*;
-pub use val::*;
-pub use node::*;
-
-use token::*;
+use super::{token::*, Body, Node, Parsable, ParserError, ParserErrors, TokenCursor};
 
 #[derive(Debug)]
 pub struct Module {

src/parser/v1/val.rs

@@ -2,7 +2,7 @@ use super::{CharCursor, MaybeParsable, ParserError, ParserErrors, Symbol, Token,
 use std::fmt::Debug;
 
 #[derive(Clone, PartialEq, Eq)]
-pub enum Val {
+pub enum Literal {
     String(String),
     Char(char),
     Number(Number),
@@ -16,7 +16,7 @@ pub struct Number {
     pub ty: Option<String>,
 }
 
-impl MaybeParsable for Val {
+impl MaybeParsable for Literal {
     fn maybe_parse(cursor: &mut TokenCursor, _: &mut ParserErrors) -> Result<Option<Self>, ParserError> {
         let inst = cursor.expect_peek()?;
         let mut res = match &inst.token {
@@ -85,7 +85,7 @@ pub fn string_from(cursor: &mut CharCursor) -> Result<String, ParserError> {
     }
 }
 
-impl Debug for Val {
+impl Debug for Literal {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
             Self::String(str) => str.fmt(f),

src/parser/v2/mod.rs

@@ -1,8 +1,17 @@
-use std::{ffi::OsStr, io::{BufRead, BufReader}};
+use std::io::{BufRead, BufReader};
 
-use parser::{print_error, CharCursor, Module, Statement};
+mod body;
+mod cursor;
+mod error;
+mod expr;
+mod module;
+mod util;
 
-mod parser;
+pub use body::*;
+pub use cursor::*;
+pub use error::*;
+pub use expr::*;
+pub use module::*;
 
 pub fn parse_file(file: &str) {
     match Module::parse(&mut CharCursor::from(file)) {

src/parser/v2/module.rs

@@ -1,16 +1,5 @@
 use std::{collections::HashSet, fmt::Debug, sync::LazyLock};
-
-mod body;
-mod cursor;
-mod error;
-mod expr;
-mod util;
-
-pub use body::*;
-pub use cursor::*;
-pub use error::*;
-pub use expr::*;
-use util::WHITESPACE_SET;
+use super::{util::WHITESPACE_SET, Body, CharCursor, ParserError};
 
 #[derive(Debug)]
 pub struct Module {

src/util/bits.rs

@@ -0,0 +1,120 @@
+pub const fn u(x: i32) -> u32 {
+    unsafe { std::mem::transmute(x) }
+}
+
+pub const fn low_mask(high: u32, low: u32) -> u32 {
+    (2u32.unbounded_shl(high - low)).wrapping_sub(1)
+}
+
+pub const fn mask(high: u32, low: u32) -> u32 {
+    low_mask(high, low).unbounded_shl(low)
+}
+
+pub const fn bits(x: i32, high: u32, low: u32) -> u32 {
+    let x = u(x);
+    x.unbounded_shr(low) & low_mask(high, low)
+}
+
+pub const fn bit(x: i32, i: u32) -> u32 {
+    let x = u(x);
+    x.unbounded_shr(i) & 2u32 << i
+}
+
+pub const fn in_bit_range(x: i32, high: u32, low: u32) -> bool {
+    if x < 0 {
+        if high == low {
+            return false;
+        }
+        (bits(x, high - 1, low) | !mask(high - 1, low)) == u(x)
+    } else {
+        bits(x, high, low) << low == u(x)
+    }
+}
+
+// use std::ops::{Add, Shl, Shr};
+//
+// pub const fn u(x: i32) -> u32 {
+//     unsafe { std::mem::transmute(x) }
+// }
+//
+// pub const fn low_mask(high: u8, low: u8) -> u32 {
+//     (2u32.unbounded_shl(high - low)).wrapping_sub(1)
+// }
+//
+// pub const fn mask(high: u8, low: u8) -> u32 {
+//     low_mask(high, low).unbounded_shl(low)
+// }
+//
+// pub const fn bits(x: i32, high: u8, low: u8) -> u32 {
+//     let x = u(x);
+//     x.unbounded_shr(low) & low_mask(high, low)
+// }
+//
+// pub const fn bit(x: i32, i: u32) -> u32 {
+//     let x = u(x);
+//     x.unbounded_shr(i) & 2u32 << i
+// }
+//
+// pub const fn in_bit_range<T: Shl<u8, Output = T> + Shr<u8, Output = T>>(
+//     x: T,
+//     high: u8,
+//     low: u8,
+// ) -> bool {
+//     if x < 0 {
+//         if high == low {
+//             return false;
+//         }
+//         (bits(x, high - 1, low) | !mask(high - 1, low)) == u(x)
+//     } else {
+//         bits(x, high, low) << low == u(x)
+//     }
+// }
+
+// pub struct Bits<
+//     T: Shl<u8, Output = T> + Shr<u8, Output = T>,
+//     const S: bool,
+//     const H: u8,
+//     const L: u8,
+// >(T);
+// pub struct U32Bits<const H: u32, const L: u32>(u32);
+//
+// impl<T: Shl<u8, Output = T> + Shr<u8, Output = T> + Add<u8, Output = T>, const S: bool, const H: u8, const L: u8>
+//     Bits<T, S, H, L>
+// {
+//     pub const fn new(val: T) -> Self {
+//         assert!(in_bit_range(val, H, L));
+//         Self(val + L)
+//     }
+// }
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn get_bits() {
+        assert_eq!(bits(0b10111010, 5, 3), 0b111);
+        assert_eq!(bits(0b10111010, 7, 5), 0b101);
+        assert_eq!(bits(0b10111010, 2, 0), 0b010);
+        assert_eq!(bits(0b10111010, 7, 7), 0b1);
+        assert_eq!(bits(0b1, 0, 0), 0b1);
+        assert_eq!(bits(0b1, 1, 1), 0b0);
+    }
+
+    #[test]
+    fn range() {
+        assert!(!in_bit_range(0b00111100, 5, 3));
+        assert!(!in_bit_range(0b00111100, 4, 2));
+        assert!(in_bit_range(0b000111100, 5, 2));
+        assert!(in_bit_range(0b000000001, 0, 0));
+        assert!(in_bit_range(0b000001000, 3, 3));
+
+        assert!(!in_bit_range(-3, 1, 0));
+        assert!(!in_bit_range(-5, 2, 2));
+        assert!(!in_bit_range(-5, 4, 3));
+        assert!(in_bit_range(-1, 1, 0));
+        assert!(in_bit_range(-4, 2, 0));
+        assert!(in_bit_range(-5, 3, 2));
+    }
+}

src/util/mod.rs

@@ -1,38 +1,5 @@
-use core::fmt;
+mod padder;
+mod bits;
 
-pub struct Padder<'buf> {
-    buf: &'buf mut (dyn fmt::Write + 'buf),
-    on_newline: bool,
-}
-
-impl fmt::Write for Padder<'_> {
-    fn write_str(&mut self, s: &str) -> fmt::Result {
-        for s in s.split_inclusive('\n') {
-            if self.on_newline {
-                self.buf.write_str("    ")?;
-            }
-
-            self.on_newline = s.ends_with('\n');
-            self.buf.write_str(s)?;
-        }
-
-        Ok(())
-    }
-
-    fn write_char(&mut self, c: char) -> fmt::Result {
-        if self.on_newline {
-            self.buf.write_str("    ")?;
-        }
-        self.on_newline = c == '\n';
-        self.buf.write_char(c)
-    }
-}
-
-impl<'buf> Padder<'buf> {
-    pub fn new(buf: &'buf mut (dyn fmt::Write + 'buf)) -> Self {
-        Self {
-            buf,
-            on_newline: false,
-        }
-    }
-}
+pub use padder::*;
+pub use bits::*;

src/util/padder.rs

@@ -0,0 +1,38 @@
+use core::fmt;
+
+pub struct Padder<'buf> {
+    buf: &'buf mut (dyn fmt::Write + 'buf),
+    on_newline: bool,
+}
+
+impl fmt::Write for Padder<'_> {
+    fn write_str(&mut self, s: &str) -> fmt::Result {
+        for s in s.split_inclusive('\n') {
+            if self.on_newline {
+                self.buf.write_str("    ")?;
+            }
+
+            self.on_newline = s.ends_with('\n');
+            self.buf.write_str(s)?;
+        }
+
+        Ok(())
+    }
+
+    fn write_char(&mut self, c: char) -> fmt::Result {
+        if self.on_newline {
+            self.buf.write_str("    ")?;
+        }
+        self.on_newline = c == '\n';
+        self.buf.write_char(c)
+    }
+}
+
+impl<'buf> Padder<'buf> {
+    pub fn new(buf: &'buf mut (dyn fmt::Write + 'buf)) -> Self {
+        Self {
+            buf,
+            on_newline: false,
+        }
+    }
+}